WorldWideScience

Sample records for leukemia virus antibody

  1. Antibodies to the human T-cell lymphoma/leukemia virus type I in Dutch haemophiliacs

    NARCIS (Netherlands)

    Goudsmit, J.; Miedema, F.; Breederveld, C.; Terpstra, F.; Roos, M.; Schellekens, P.; Melief, C.

    1986-01-01

    95 Dutch haemophiliacs were tested for antibodies to membrane antigens on cells infected with human T-cell leukemia virus type I (HTLV-I-MA) by indirect immunofluorescence and to purified HTLV-I by enzyme-linked immunosorbent assay. Antibodies to HTLV-I-MA were present in 8 of 95 (8%) haemophiliacs,

  2. Antibody responses against xenotropic murine leukemia virus-related virus envelope in a murine model.

    Directory of Open Access Journals (Sweden)

    Natalia Makarova

    2011-04-01

    Full Text Available Xenotropic murine leukemia virus-related virus (XMRV was recently discovered to be the first human gammaretrovirus that is associated with chronic fatigue syndrome and prostate cancer (PC. Although a mechanism for XMRV carcinogenesis is yet to be established, this virus belongs to the family of gammaretroviruses well known for their ability to induce cancer in the infected hosts. Since its original identification XMRV has been detected in several independent investigations; however, at this time significant controversy remains regarding reports of XMRV detection/prevalence in other cohorts and cell type/tissue distribution. The potential risk of human infection, coupled with the lack of knowledge about the basic biology of XMRV, warrants further research, including investigation of adaptive immune responses. To study immunogenicity in vivo, we vaccinated mice with a combination of recombinant vectors expressing codon-optimized sequences of XMRV gag and env genes and virus-like particles (VLP that had the size and morphology of live infectious XMRV.Immunization elicited Env-specific binding and neutralizing antibodies (NAb against XMRV in mice. The peak titers for ELISA-binding antibodies and NAb were 1:1024 and 1:464, respectively; however, high ELISA-binding and NAb titers were not sustained and persisted for less than three weeks after immunizations.Vaccine-induced XMRV Env antibody titers were transiently high, but their duration was short. The relatively rapid diminution in antibody levels may in part explain the differing prevalences reported for XMRV in various prostate cancer and chronic fatigue syndrome cohorts. The low level of immunogenicity observed in the present study may be characteristic of a natural XMRV infection in humans.

  3. Human monoclonal antibodies reactive with human myelomonocytic leukemia cells.

    Science.gov (United States)

    Posner, M R; Santos, D J; Elboim, H S; Tumber, M B; Frackelton, A R

    1989-04-01

    Peripheral blood mononuclear cells from a patient with chronic myelogenous leukemia (CML), in remission, were depleted of CD8-positive T-cells and cultured with Epstein-Barr virus. Four of 20 cultures (20%) secreted human IgG antibodies selectively reactive with the cell surfaces of certain human leukemia cell lines. Three polyclonal, Epstein-Barr virus-transformed, B-cell lines were expanded and fused with the human-mouse myeloma analogue HMMA2.11TG/O. Antibody from secreting clones HL 1.2 (IgG1), HL 2.1 (IgG3), and HL 3.1 (IgG1) have been characterized. All three react with HL-60 (promyelocytic), RWLeu4 (CML promyelocytic), and U937 (monocytic), but not with KG-1 (myeloblastic) or K562 (CML erythroid). There is no reactivity with T-cell lines, Burkitt's cell lines, pre-B-leukemia cell lines, or an undifferentiated CML cell line, BV173. Leukemic cells from two of seven patients with acute myelogenous leukemia and one of five with acute lymphocytic leukemia react with all three antibodies. Normal lymphocytes, monocytes, polymorphonuclear cells, red blood cells, bone marrow cells, and platelets do not react. Samples from patients with other diverse hematopoietic malignancies showed no reactivity. Immunoprecipitations suggest that the reactive antigen(s) is a lactoperoxidase iodinatable series of cell surface proteins with molecular weights of 42,000-54,000 and a noniodinatable protein with a molecular weight of 82,000. Based on these data these human monoclonal antibodies appear to react with myelomonocytic leukemic cells and may detect a leukemia-specific antigen or a highly restricted differentiation antigen.

  4. Diagnostic performance of an indirect enzyme-linked immunosorbent assay (ELISA) to detect bovine leukemia virus antibodies in bulk-tank milk samples

    Science.gov (United States)

    Nekouei, Omid; Durocher, Jean; Keefe, Greg

    2016-01-01

    This study assessed the diagnostic performance of a commercial ELISA for detecting bovine leukemia virus antibodies in bulk-tank milk samples from eastern Canada. Sensitivity and specificity of the test were estimated at 97.2% and 100%, respectively. The test was recommended as a cost-efficient tool for large-scale screening programs. PMID:27429469

  5. Chimeras of receptors for gibbon ape leukemia virus/feline leukemia virus B and amphotropic murine leukemia virus reveal different modes of receptor recognition by retrovirus

    DEFF Research Database (Denmark)

    Pedersen, Lene; Johann, Stephen V; van Zeijl, Marja

    1995-01-01

    Glvr1 encodes the human receptor for gibbon ape leukemia virus (GALV) and feline leukemia virus subgroup B (FeLV-B), while the related gene Glvr2 encodes the human receptor for amphotropic murine leukemia viruses (A-MLVs). The two proteins are 62% identical in their amino acid sequences...

  6. The receptors for gibbon ape leukemia virus and amphotropic murine leukemia virus are not downregulated in productively infected cells

    Directory of Open Access Journals (Sweden)

    Eiden Maribeth V

    2011-07-01

    Full Text Available Abstract Background Over the last several decades it has been noted, using a variety of different methods, that cells infected by a specific gammaretrovirus are resistant to infection by other retroviruses that employ the same receptor; a phenomenon termed receptor interference. Receptor masking is thought to provide an earlier means of blocking superinfection, whereas receptor down regulation is generally considered to occur in chronically infected cells. Results We used replication-competent GFP-expressing viruses containing either an amphotropic murine leukemia virus (A-MLV or the gibbon ape leukemia virus (GALV envelope. We also constructed similar viruses containing fluorescence-labeled Gag proteins for the detection of viral particles. Using this repertoire of reagents together with a wide range of antibodies, we were able to determine the presence and availability of viral receptors, and detect viral envelope proteins and particles presence on the cell surface of chronically infected cells. Conclusions A-MLV or GALV receptors remain on the surface of chronically infected cells and are detectable by respective antibodies, indicating that these receptors are not downregulated in these infected cells as previously proposed. We were also able to detect viral envelope proteins on the infected cell surface and infected cells are unable to bind soluble A-MLV or GALV envelopes indicating that receptor binding sites are masked by endogenously expressed A-MLV or GALV viral envelope. However, receptor masking does not completely prevent A-MLV or GALV superinfection.

  7. Monoclonal antibodies reactive with hairy cell leukemia

    NARCIS (Netherlands)

    Visser, L; Shaw, A; Slupsky, J; Vos, H; Poppema, S

    Monoclonal antibodies reactive with hairy cell leukemia were developed to aid in the diagnosis of this subtype of B cell chronic lymphocytic leukemia and to gain better insight into the origin of hairy cells. Three antibodies were found to be of value in the diagnosis of hairy cell leukemia.

  8. Selective host range restriction of goat cells for recombinant murine leukemia virus and feline leukemia virus type A.

    OpenAIRE

    Fischinger, P J; Thiel, H J; Blevins, C S; Dunlop, N M

    1981-01-01

    We isolated a strain of normal goat fibroblasts which was uniquely selective in that it allowed the replication of xenotropic murine leukemia virus but not polytropic recombinant murine leukemia virus. In addition, feline leukemia virus type A replication was severely diminished in these goat cells, whereas feline leukemia virus type B and feline endogenous RD114-CCC viruses replicated efficiently. No other known cells exhibit this pattern of virus growth restriction. These goat cells allow t...

  9. Seroprevalence of feline leukemia virus and feline immunodeficiency virus infection among cats in Canada.

    Science.gov (United States)

    Little, Susan; Sears, William; Lachtara, Jessica; Bienzle, Dorothee

    2009-06-01

    The purposes of this study were to determine the seroprevalence of feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) infection among cats in Canada and to identify risk factors for seropositivity. Signalment, lifestyle factors, and test results for FeLV antigen and FIV antibody were analyzed for 11 144 cats from the 10 Canadian provinces. Seroprevalence for FIV antibody was 4.3% and seroprevalence for FeLV antigen was 3.4%. Fifty-eight cats (0.5%) were seropositive for both viruses. Seroprevalence varied geographically. Factors such as age, gender, health status, and lifestyle were significantly associated with risk of FeLV and FIV seropositivity. The results suggest that cats in Canada are at risk of retrovirus infection and support current recommendations that the retrovirus status of all cats should be known.

  10. Xenotropic murine leukemia virus-related virus does not pose a risk to blood recipient safety.

    Science.gov (United States)

    Dodd, Roger Y; Hackett, John; Linnen, Jeffrey M; Dorsey, Kerri; Wu, Yanyun; Zou, Shimian; Qiu, Xiaoxing; Swanson, Priscilla; Schochetman, Gerald; Gao, Kui; Carrick, James M; Krysztof, David E; Stramer, Susan L

    2012-02-01

    When xenotropic murine leukemia virus-related virus (XMRV) was first reported in association with chronic fatigue syndrome, it was suggested that it might offer a risk to blood safety. Thus, the prevalence of the virus among blood donors and, if present, its transmissibility by transfusion need to be defined. Two populations of routine blood donor samples (1435 and 13,399) were obtained for prevalence evaluations; samples from a linked donor-recipient repository were also evaluated. Samples were tested for the presence of antibodies to XMRV-related recombinant antigens and/or for XMRV RNA, using validated, high-throughput systems. The presence of antibodies to XMRV could not be confirmed among a total of 17,249 blood donors or recipients (0%; 95% confidence interval [CI], 0%-0.017%); 1763 tested samples were nonreactive for XMRV RNA (0%; 95% CI, 0%-0.17%). Evidence of infection was absent from 109 recipients and 830 evaluable blood samples tested after transfusion of a total of 3741 blood components. XMRV and related murine leukemia virus (MLV) markers are not present among a large population of blood donors and evidence of transfusion transmission could not be detected. Thus, these viruses do not currently pose a threat to blood recipient safety and further actions relating to XMRV and MLV are not justified. © 2012 American Association of Blood Banks.

  11. Anti-ATLA (antibody to adult T-cell leukemia-lymphoma virus-associated antigen)-negative adult T-cell leukemia-lymphoma.

    Science.gov (United States)

    Shimoyama, M; Minato, K; Tobinai, K; Nagai, M; Setoya, T; Watanabe, S; Hoshino, H; Miwa, M; Nagoshi, H; Ichiki, N; Fukushima, N; Sugiura, K; Funaki, N

    1983-01-01

    Five cases of adult T-cell leukemia-lymphoma (ATL) having typical clinicohematologic and morphologic features but negative for anti-ATLA [antibody to ATL virus (ATLV)-associated antigen (ATLA)] are presented. Some differences in immunologic, epidemiologic, and serologic data between anti-ATLA-positive and -negative ATLs are also described. Expression of ATLA in early primary cultured leukemic cells was found to be negative in three patients tested (Cases 1, 2 and 4), however, a long-term cultured cell line, ATL-6A, derived from peripheral blood leukemia cells from Case 1, was found to express ATLA. Mother of Case 1 and a daughter of Case 2 were anti-ATLA negative. These results indicate that ATLV was involved in certain anti-ATLA-negative ATL patients, at least in Case 1, and that the patient had no detectable immune response against ATLV and ATLA. However, in other cases in which no ATLA reactivity of serum and no ATLA expression in cultured leukemic cells were observed, another possibility such as activation of an unknown cellular oncogene specific for ATL without ATLV involvement may be considered. In order to prove these possibilities definitely, it is necessary to elucidate whether or not proviral DNA of ATLV is integrated into chromosomal DNA of ATL cells and to find a cellular oncogene specific for ATL in the future.

  12. Evidence of feline immunodeficiency virus, feline leukemia virus, and Toxoplasma gondii in feral cats on Mauna Kea, Hawaii.

    Science.gov (United States)

    Danner, Raymond M; Goltz, Daniel M; Hess, Steven C; Banko, Paul C

    2007-04-01

    We determined prevalence to feline immunodeficiency virus (FIV) antibodies, feline leukemia virus (FeLV) antigen, and Toxoplasma gondii antibodies in feral cats (Felis catus) on Mauna Kea Hawaii from April 2002 to May 2004. Six of 68 (8.8%) and 11 of 68 (16.2%) cats were antibody positive to FIV and antigen positive for FeLV, respectively; 25 of 67 (37.3%) cats were seropositive to T. gondii. Antibodies to FeLV and T. gondii occurred in all age and sex classes, but FIV occurred only in adult males. Evidence of current or previous infections with two of these infectious agents was detected in eight of 64 cats (12.5%). Despite exposure to these infectious agents, feral cats remain abundant throughout the Hawaiian Islands.

  13. Evidence of feline immunodeficiency virus, feline leukemia virus, and Toxoplasma gondii in feral cats on Mauna Kea, Hawaii

    Science.gov (United States)

    Danner, R.M.; Goltz, Dan M.; Hess, S.C.; Banko, P.C.

    2007-01-01

    We determined prevalence to feline immunodeficiency virus (FIV) antibodies, feline leukemia virus (FeLV) antigen, and Toxoplasma gondii antibodies in feral cats (Felis catus) on Mauna Kea Hawaii from April 2002 to May 2004. Six of 68 (8.8%) and 11 of 68 (16.2%) cats were antibody positive to FIV and antigen positive for FeLV, respectively; 25 of 67 (37.3%) cats were seropositive to T. gondii. Antibodies to FeLV and T. gondii occurred in all age and sex classes, but FIV occurred only in adult males. Evidence of current or previous infections with two of these infectious agents was detected in eight of 64 cats (12.5%). Despite exposure to these infectious agents, feral cats remain abundant throughout the Hawaiian Islands. ?? Wildlife Disease Association 2007.

  14. High incidence of antibodies to HTLV-I tax in blood relatives of adult T cell leukemia patients.

    Science.gov (United States)

    Okayama, A; Chen, Y M; Tachibana, N; Shioiri, S; Lee, T H; Tsuda, K; Essex, M

    1991-01-01

    Adult T cell leukemia (ATL) is caused by the human T cell leukemia virus type I (HTLV-I). Although the mechanisms of the leukemogenic process are unknown, the tax gene may have a role in this process. Because clustering occurs with HTLV-I and ATL, members of ATL families were examined for antibodies to the tax protein and compared with matched HTLV-I-positive blood donors. To investigate the antibody response to this protein, a plasmid, pBHX-4, was constructed to express a recombinant tax protein (r-tax). For ATL patients and their HTLV-I antibody-positive blood relatives, the rate of seroreactivity with the r-tax protein was 67.3% (35/52), compared with 51.6% (97/188) for HTLV-I antibody-positive control blood donors (P less than .05). The difference between direct offspring of ATL patients and matched HTLV-I blood donors was even greater (84.2% [16/91] vs. 44.2% [42/95]; P less than .005). Thus, tax antibody positivity in direct offspring of ATL patients may reflect differences in time or route of HTLV-I infection. Alternatively, it might reflect genetic differences in host susceptibility or virus strain.

  15. Seroprevalence of Toxoplasma gondii and concurrent Bartonella spp., feline immunodeficiency virus, feline leukemia virus, and Dirofilaria immitis infections in Egyptian cats.

    Science.gov (United States)

    Al-Kappany, Y M; Lappin, M R; Kwok, O C H; Abu-Elwafa, S A; Hilali, M; Dubey, J P

    2011-04-01

    Toxoplasma gondii and Bartonella spp. are zoonotic pathogens of cats. Feline immunodeficiency virus (FIV) and feline leukemia virus (FeLv) are related to human immunodeficiency virus and human leukemia virus, respectively, and these viruses are immunosuppressive. In the present study, the prevalence of antibodies to T. gondii , Bartonella spp., FIV, as well as FeLv and Dirofilaria immitis antigens was determined in sera from feral cats (Felis catus) from Cairo, Egypt. Using a modified agglutination test, antibodies to T. gondii were found in 172 (95.5%) of the 180 cats with titers of 1∶5 in 9, 1∶10 in 9, 1∶20 in 3, 1∶40 in 5, 1∶80 in 5, 1∶160 in 15, 1∶320 in 22, and 1∶640 or higher in 104. Thus, 57.4% had high T. gondii titers. Antibodies to Bartonella spp. were found in 105 (59.6%) of 178, with titers of 1∶64 in 45, 1∶128 in 39, 1∶256 in 13, 1∶512 in 3, 1∶1,024 in 4, and 1∶2,048 in 1 cat. Antibodies to FIV were detected in 59 (33.9%) of 174 cats. Of 174 cats tested, antigens to FeLv, and D. immitis were detected in 8 (4.6%) and 6 (3.4%) cats, respectively. The results indicate a high prevalence of T. gondii, Bartonella spp., and FIV infections in cats from Cairo, Egypt. This is the first report of Bartonella spp., and D. immitis infection in cats in Egypt.

  16. Friend and Moloney murine leukemia viruses specifically recombine with different endogenous retroviral sequences to generate mink cell focus-forming viruses.

    Science.gov (United States)

    Evans, L H; Cloyd, M W

    1985-01-01

    A group of mink cell focus-forming (MCF) viruses was derived by inoculation of NFS/N mice with Moloney murine leukemia virus (Mo-MuLV 1387) and was compared to a similarly derived group of MCF viruses from mice inoculated with Friend MuLV (Fr-MuLV 57). Antigenic analyses using monoclonal antibodies specific for MCF virus and xenotropic MuLV envelope proteins and genomic structural analyses by RNase T1-resistant oligonucleotide finger-printing indicated that the Moloney and Friend MCF viruses arose by recombination of the respective ecotropic MuLVs with different endogenous retrovirus sequences of NFS mice.

  17. Optimization of a method for the detection of immunopotentiating antibodies against serotype 1 of dengue virus

    International Nuclear Information System (INIS)

    Soto Garita, Claudio

    2014-01-01

    An immunopotentiation trial has used sera from dengue seropositive patients from Costa Rica's endemic areas. The detection and semi-quantification of immunopotentiating antibodies were optimized against dengue virus serotype 1. The cell line K562 (human erythromyeloblastoid leukemia cells) has been more efficient than the U937 (human histiocytic lymphoma cells). A more adequate detection of immunopotentiating antibodies was determined. The optimal infection and virus-antibody incubation parameters are demonstrated for the detection of immunopotentiating antibodies with the immunostaining technique. The immuno-optimized assay has allowed the detection and semi-quantification of immunopotentiating antibodies against serotype 1 of dengue virus. Samples of strong positive, weak positive and dengue negative sera are analyzed. The end has been to evaluate the usefulness in the detection and semi-quantification of immunopotentiating antibodies. The presence of immunopotentiating antibodies was demonstrated against dengue virus serotype 1 in endemic zones of Costa Rica, to complement with the evaluation of the other existing serotypes is recommended [es

  18. Anti-human T-lymphotropic virus type-I antibodies in atomic-bomb survivors

    Energy Technology Data Exchange (ETDEWEB)

    Matsuo, Tatsuki; Nakashima, Eiji; Carter, R.L. [Radiation Effects Research Foundation, Nagasaki (Japan). Nagasaki Branch] [and others

    1995-03-01

    Adult T-cell leukemia (ATL), induced by human T-lymphotropic virus type-I (HTLV-I), is endemic in Nagasaki, Japan. To investigate the effects of atomic-bomb radiation on development of this specific type of leukemia, 6182 individuals in the Radiation Effects Research Foundation (RERF) Adult Health Study sample in Hiroshima and Nagasaki were examined for positive rate of HTLV-I antibody. Several lymphocyte parameters were also studied for 70 antibody-positive subjects in Nagasaki. The HTLV-I antibody-positive rate was higher in Nagasaki (6.36%) than in Hiroshima (0.79%) and significantly increased with increasing age, but no association was observed with radiation dose. Whether relationship existed between antibody titer levels and radiation dose among antibody-positive subjects was not clear. The frequency of abnormal lymphocytes tended to be higher in antibody-positive subjects than in antibody-negative subjects, and higher in females than in males regardless of radiation dose. The lymphocyte count was lower in antibody-positive subjects than in antibody-negative subjects and lower in female than in male subjects. No evidence was found to suggest that atomic-bomb radiation plays an important role in HTLV-I infection. (author).

  19. Expression of antigens coded in murine leukemia viruses on thymocytes of allogeneic donor origin in AKR mice following syngeneic or allogeneic bone marrow transplantation

    International Nuclear Information System (INIS)

    Wustrow, T.P.; Good, R.A.

    1985-01-01

    Removal of T-lymphocytes from marrow inoculum with monoclonal antibody plus complement permitted establishment of long-lived allogeneic chimeras between C57BL/6 and AKR/J mice. Development of leukemia was prevented for 15 mo. Protection from leukemia occurred with both young (4 wk) and older (4 mo) recipients. AKR mice reconstituted with syngeneic marrow or control AKR mice all developed leukemia-lymphoma before 1 yr of age. During spontaneous lymphomagenesis in AKR mice, amplified expression of gag or env gene-coded virus antigens on the surface of thymocytes preceded leukemia development and evidence for amplification of other virus genes. These changes generally appeared before 6 mo. Similar viral gene expression and viral gene amplification occurred in the thymus and spleen cells of leukemia-resistant chimeric mice. Using monoclonal antibodies to Mr 70,000 glycoprotein epitopes characteristic of ecotropic, xenotropic, or dualtropic viruses, antigens marking each virus form were found on thymocytes of allogeneic 4-wk and 4-mo chimeras as well as on the cells of AKR mice and of AKR mice reconstituted with syngeneic marrow. Flow cytometric analysis showed amplification of the virus genes in mice protected from leukemia-lymphoma by allogeneic bone marrow transplantation from leukemia-resistant mice. Allogeneic chimeras and syngeneically transplanted mice both showed evidence of accelerated viremia and of recombinant virus formation. The findings suggest that an event essential to leukemogenesis which occurs within the AKR lymphoid cells or their environment is lacking in the allogeneic chimeras. The nature of this influence of a resistance gene or genes introduced into AKR mice by allogeneic bone marrow transplantation deserves further study

  20. Hepatitis A virus antibody

    International Nuclear Information System (INIS)

    Novak, J.; Kselikova, M.; Urbankova, J.

    1980-01-01

    A description is presented of a radioimmunoassay designed to prove the presence of the antibody against the hepatitis A virus (HA Ab, anti-Ha) using an Abbott HAVAB set. This proof as well as the proof of the antibody against the nucleus of the hepatitis B virus is based on competition between a normal antibody against hepatitis A virus and a 125 I-labelled antibody for the binding sites of a specific antigen spread all over the surface of a tiny ball; this is then indirect proof of the antibody under investigation. The method is described of reading the results from the number of impulses per 60 seconds: the higher the titre of the antibody against the hepatitis A virus in the serum examined, the lower the activity of the specimen concerned. The rate is reported of incidence of the antibody against the hepatitis A virus in a total of 68 convalescents after hepatitis A; the antibody was found in 94.1%. The immunoglobulin made from the convalescents' plasma showed the presence of antibodies in dilutions as high as 1:250 000 while the comparable ratio for normal immunoglobulin Norga was only 1:2500. Differences are discussed in the time incidence of the antibodies against the hepatitis A virus, the antibodies against the surface antigen of hepatitis B, and the antibody against the nucleus of the hepatitis V virus. (author)

  1. Anti-ATLA (antibody to adult T-cell leukemia virus-associated antigen), highly positive in OKT4-positive mature T-cell malignancies.

    Science.gov (United States)

    Tobinai, K; Nagai, M; Setoya, T; Shibata, T; Minato, K; Shimoyama, M

    1983-01-01

    Serum or plasma specimens from 252 patients with lymphoid malignancies were screened for reactivity with adult T-cell leukemia virus-associated antigen (ATLA), and the relationship between the immunologic phenotype of the tumor cells and ATLA reactivity was determined. Anti-ATLA antibodies were found in 24 (29.3%) of 82 patients with T-cell malignancy. In contrast, the antibodies were found in none of the 106 patients with B-cell malignancy and only rarely in patients with other lymphoid malignancies without blood transfusions. Among the patients with T-cell malignancy, anti-ATLA antibodies were found in 23 (45.1%) of the 51 patients with OKT4-positive mature T-cell (inducer/helper T-cell) malignancy, but in none of the patients with T-cell malignancy of pre-T, thymic T-cell or OKT8-positive mature T-cell (suppressor/cytotoxic T-cell) phenotype. Furthermore, among the OKT4-positive mature T-cell malignancies, the antibodies were found in 16 (84.2%) of 19 patients with ATL and in 5 (27.8%) of 18 patients with mature (peripheral) T-cell lymphoma, in none of four with typical T-chronic lymphocytic leukemia, in one of nine with mycosis fungoides and in the one patient with small-cell variant of Sézary's syndrome. These results suggest that anti-ATLA positive T-cell malignancies with OKT4-positive mature T-cell phenotype must be the same disease, because it is highly possible that they have the same etiology and the same cellular origin. In the atypical cases, it seems necessary to demonstrate monoclonal integration of proviral DNA of ATLV or HTLV into the tumor cells in order to establish the final diagnosis of ATL.

  2. Prevalence of human T-lymphotropic virus type I and type II antibody among blood donors in Eastern Saudi Arabia.

    Science.gov (United States)

    Ul-Hassan, Zahoor; Al-Bahrani, Ahmad T; Panhotra, Bodh R

    2004-10-01

    Human T-cell leukemia/lymphoma virus type I and type II (HTLV-I/II) infections can be transfusion associated, leading to tropical paraparesis, myelopathy and other neurological disorders. The aim of this study is to circumvent the risk of transmission through blood transfusion and to describe the prevalence of HTLV-I/II antibody among blood donors of Al-Hasa region and the cost effectiveness of screening blood donors. The study was conducted at the Department of Laboratory and Blood Bank, King Fahad Hospital, Al-Hofuf, Al-Hasa, Kingdom of Saudi Arabia during the period of 1997 to 2003. A total of 47426 blood donors were screened for HTLV-I/II antibody by enzyme-linked immunosorbent assay test, during the 7 years of study period. The positive samples were confirmed by western blot analysis. Overall, HTLV-I antibody positivity (confirmed by western blot) was 3/47426 (0.006%). Out of 3 donors positive for HTLV-I antibody during 1997 to 1998, 2 were expatriates (Indian) and one was native Saudi donor. Human T-cell leukemia/lymphoma virus type I antibody positivity among the native Saudi donors was 1/47426 (0.002%) (2/100000 blood donors). None of the donor were positive for HTLV-II antibody. During the last 5 consecutive years of the study period (1999-2003), none of the donor was positive for HTLV-I/II antibody. Al-Hasa region is non-endemic for HTLV-I/II virus infections. Screening of native Saudi blood donors for these viruses does not appear to be cost effective.

  3. Antibody response to vaccines for rhinotracheitis, caliciviral disease, panleukopenia, feline leukemia, and rabies in tigers (Panthera tigris) and lions (Panthera leo).

    Science.gov (United States)

    Risi, Emmanuel; Agoulon, Albert; Allaire, Franck; Le Dréan-Quénec'hdu, Sophie; Martin, Virginie; Mahl, Philippe

    2012-06-01

    This article presents the results of a study of captive tigers (Panthera tigris) and lions (Panthera leo) vaccinated with a recombinant vaccine against feline leukemia virus; an inactivated adjuvanted vaccine against rabies virus; and a multivalent modified live vaccine against feline herpesvirus, calicivirus, and panleukopenia virus. The aim of the study was to assess the immune response and safety of the vaccines and to compare the effects of the administration of single (1 ml) and double (2 ml) doses. The animals were separated into two groups and received either single or double doses of vaccines, followed by blood collection for serologic response for 400 days. No serious adverse event was observed, with the exception of abortion in one lioness, potentially caused by the incorrect use of the feline panleukopenia virus modified live vaccine. There was no significant difference between single and double doses for all vaccines. The recombinant vaccine against feline leukemia virus did not induce any serologic response. The vaccines against rabies and feline herpesvirus induced a significant immune response in the tigers and lions. The vaccine against calicivirus did not induce a significant increase in antibody titers in either tigers or lions. The vaccine against feline panleukopenia virus induced a significant immune response in tigers but not in lions. This report demonstrates the value of antibody titer determination after vaccination of nondomestic felids.

  4. Comparative analysis of radiation- and virus-induced leukemias in BALB/c mice

    International Nuclear Information System (INIS)

    Newcomb, E.W.; Binari, R.; Fleissner, E.

    1985-01-01

    Endogenous murine leukemia virus (MuLV) proviral copies were analyzed in thymomas induced in normal BALB/c (Fv-1b) and in Fv-1n congenic mice by X-irradiation. Both strains of mice developed leukemia with similar kinetics, indicating that N-tropism of endogenous MuLV was not a rate-limiting factor in development of disease. Southern blot analysis, using a probe specific for ecotropic virus and for ecotropic-specific sequences retained in pathogenic, env-recombinant viruses, showed that the majority of radiation leukemias lacked newly acquired, clonally integrated, proviruses. This was in contrast to virus-induced leukemias, which routinely exhibited several new proviral integration sites. When an internal proviral DNA restriction fragment was monitored, some radiation leukemias showed evidence of nonclonal infection, accounting for more frequent isolation of infectious virus from such leukemias. Differences in expression of T-cell surface antigens were found in X-ray-induced and virus-induced leukemias. All radiation leukemias were TL positive, whereas virus-induced leukemias were primarily negative for TL. Some differences were also found in Lyt-1 and Lyt-2 expression. The data as a whole suggest that, in the majority of cases, radiation leukemogenesis is not initiated by a viral route--that is, the sort of viral mechanism for which exogenous infection by known pathogenic MuLV is the paradigm

  5. Anti-Bovine Programmed Death-1 Rat–Bovine Chimeric Antibody for Immunotherapy of Bovine Leukemia Virus Infection in Cattle

    Directory of Open Access Journals (Sweden)

    Tomohiro Okagawa

    2017-06-01

    Full Text Available Blockade of immunoinhibitory molecules, such as programmed death-1 (PD-1/PD-ligand 1 (PD-L1, is a promising strategy for reinvigorating exhausted T cells and preventing disease progression in a variety of chronic infections. Application of this therapeutic strategy to cattle requires bovinized chimeric antibody targeting immunoinhibitory molecules. In this study, anti-bovine PD-1 rat–bovine chimeric monoclonal antibody 5D2 (Boch5D2 was constructed with mammalian expression systems, and its biochemical function and antiviral effect were characterized in vitro and in vivo using cattle infected with bovine leukemia virus (BLV. Purified Boch5D2 was capable of detecting bovine PD-1 molecules expressed on cell membranes in flow cytometric analysis. In particular, Biacore analysis determined that the binding affinity of Boch5D2 to bovine PD-1 protein was similar to that of the original anti-bovine PD-1 rat monoclonal antibody 5D2. Boch5D2 was also capable of blocking PD-1/PD-L1 binding at the same level as 5D2. The immunomodulatory and therapeutic effects of Boch5D2 were evaluated by in vivo administration of the antibody to a BLV-infected calf. Inoculated Boch5D2 was sustained in the serum for a longer period. Boch5D2 inoculation resulted in activation of the proliferation of BLV-specific CD4+ T cells and decrease in the proviral load of BLV in the peripheral blood. This study demonstrates that Boch5D2 retains an equivalent biochemical function to that of the original antibody 5D2 and is a candidate therapeutic agent for regulating antiviral immune response in vivo. Clinical efficacy of PD-1/PD-L1 blockade awaits further experimentation with a large number of animals.

  6. ANTIBODIES TO LEUKEMIA DIFFERENTIATION FACTOR (HLDF IN PATIENTS WITH GASTROINTESTINAL CANCER

    Directory of Open Access Journals (Sweden)

    A. I. Autenshlus

    2010-01-01

    Full Text Available Antibodies to leukemia differentiation factor (HLDF in patients with gastrointestinal cancer Abstract. Patients with gastric cancer exhibit higher levels of IgG4-antibodies to human leukemia differentiation factor (HLDF, as compared with healthy individuals, whereas, in patients with colorectal cancer, one may detect high levels of IgA anti-HDLF antibodies, along with lower levels of IgG1 class antibodies against HLDF than in control group. Among patients with gastrointestinal cancer, a positive correlation is revealed between contents of highly differentiated cells in the tumor, and IgM antibodies to HDLF. Meanwhile, a reverse relationship is noted between low differentiation of tumor cells and levels of IgG2 antibodies to HDLF in gastric cancer patients, or IgG3 antibodies to HDLF in patients with colorectal cancer.

  7. Seroprevalence of bovine immunodeficiency virus and bovine leukemia virus in draught animals in Cambodia.

    Science.gov (United States)

    Meas, S; Ohashi, K; Tum, S; Chhin, M; Te, K; Miura, K; Sugimoto, C; Onuma, M

    2000-07-01

    Since bovine immunodeficiency virus (BIV), known as bovine lentivirus, has been detected in dairy and beef cattle in various countries around the world, a prevalence study of antibodies to BIV and bovine leukemia virus (BLV) was conducted in draught animals in five provinces in Cambodia, where protozoan parasite infections were suspected in some animals. To clarify the status of draught animals including Haryana, Brahman, mixed-breed, local breed cattle and muscle water buffaloes, a total of 544 cattle and 42 buffaloes were tested, and 26.3 and 16.7%, respectively, were found positive for anti-BIV p26 antibodies determined by Western blotting. There were 5.3% positive for anti-BLV antibodies detected by immunodiffusion test among the cattle, but no reactors among buffaloes and no dual infection for both BIV and BLV was determined in this study. Peripheral blood mononuclear cells from BIV-seropositive cattle were found to have BIV-provirus DNA, as detected by polymerase chain reaction and subsequent Southern blot hybridization. This is the first evidence for the presence of BIV and BLV infections in draught animals in tropical countries such as Cambodia. This wide distribution of BIV suggests its association with problems in animal health as reported worldwide, and that a primary BIV infection can predispose death of affected animals by other aggressive pathogens or stresses.

  8. PCR and serology find no association between xenotropic murine leukemia virus-related virus (XMRV and autism

    Directory of Open Access Journals (Sweden)

    Satterfield Brent C

    2010-10-01

    Full Text Available Abstract Xenotropic murine leukemia virus-related virus (XMRV is a retrovirus implicated in prostate cancer and chronic fatigue syndrome (CFS. Press releases have suggested that it could contribute to autism spectrum disorder (ASD. In this study we used two PCR assays and one antibody assay to screen 25 blood samples from autistic children born to mothers with CFS and from 20 mixed controls including family members of the children assayed, people with fibromyalgia and people with chronic Lyme disease. Using a real-time PCR assay, we screened an additional 48 South Carolina autism disorder samples, 96 Italian ASD samples, 61 South Carolina ASD samples and 184 healthy controls. Despite having the ability to detect low copy number XMRV DNA in a large background of cellular DNA, none of the PCR assays found any evidence of XMRV infection in blood cells from patients or controls. Further, no anti-XMRV antibodies were detected, ruling out possible low level or abortive infections in blood or in other reservoirs. These results imply that XMRV is not associated with autism.

  9. Immunotherapy of murine leukemia. Efficacy of passive serum therapy of Friend leukemia virus-induced disease in immunocompromised mice

    International Nuclear Information System (INIS)

    Genovesi, E.V.; Livnat, D.; Collins, J.J.

    1983-01-01

    Previous studies have demonstrated that the passive therapy of Friend murine leukemia virus (F-MuLV)-induced disease with chimpanzee anti-F-MuLV serum is accompanied by the development of host antiviral humoral and cellular immunity, the latter measurable in adoptive transfer protocols and by the ability of serum-protected mice to resist virus rechallenge. The present study was designed to further examine the contribution of various compartments of the host immune system to serum therapy itself, as well as to the acquired antiviral immunity that develops in serum-protected mice, through the use of naturally immunocompromised animals [e.g., nude athymic mice and natural killer (NK)-deficient beige mutant mice] or mice treated with immunoabrogating agents such as sublethal irradiation, cyclophosphamide [Cytoxan (Cy)], cortisone, and 89 Sr. The studies in nude mice indicate that while mature T-cells are not needed for effective serum therapy, they do appear to be necessary for the long-term resistance of serum-protected mice to virus rechallenge and for the generation of the cell population(s) responsible for adoptive transfer of antiviral immunity. Furthermore, this acquired resistance is not due to virus neutralization by serum antibodies since antibody-negative, Cy-treated, serum-protected mice still reject the secondary virus infection. Lastly, while the immunocompromise systems examined did effect various host antiviral immune responses, none of them, including the NK-deficient beige mutation, significantly diminished the efficacy of the passive serum therapy of F-MuLV-induced disease

  10. Prevalence of antibody to adult T-cell leukemia virus-associated antigens (ATLA) in Japanese monkeys and other non-human primates.

    Science.gov (United States)

    Hayami, M; Komuro, A; Nozawa, K; Shotake, T; Ishikawa, K; Yamamoto, K; Ishida, T; Honjo, S; Hinuma, Y

    1984-02-15

    The prevalence of adult T-cell-leukemia virus (ATLV) infection was examined in Japanese monkeys living naturally in various parts of Japan and in other species of non-human primates imported into and kept in Japan. Sera of 2,650 Japanese monkeys from 41 troops throughout Japan were tested. High incidences of anti-ATLV-associated antigen (ATLA)-positive monkeys were found in most troops, not only in the endemic area of human ATL(Southwestern Japan), but also in non-endemic areas. The incidence of sero-positive individuals increased gradually with age, reaching a maximum when the animals became adult, indicating age dependency, like that found by epidemiological studies on humans. Anti-ATLA antibodies were also detected in 90 of 815 sera of imported non-human primates of 33 species other than Japanese monkeys. All the anti-ATLA sero-positive monkeys were Catarrhines (Old World monkeys), mainly macaques of Asian origin. Some sero-positive monkeys were also found among animals of African origin, but no antibody was detected in Prosimians and Platyrrhines (New World monkeys). The clear-cut difference between the geographical distribution of sero-positive simians and that of humans indicates the improbability of direct transmission of ATLV from simians to humans.

  11. Analysis of peroxidase-negative acute unclassifiable leukemias by monoclonal antibodies. 1. Acute myelogenous leukemia and acute myelomonocytic leukemia.

    Science.gov (United States)

    Imamura, N; Tanaka, R; Kajihara, H; Kuramoto, A

    1988-11-01

    In this study, pretreatment peripheral and/or bone marrow blasts from 12 patients with acute unclassifiable leukemia (AUL) expressing the myeloid-related cell-surface antigen (CD 11) were isolated for further analysis. Despite a lack of myeloperoxidase (MPO) activity, 1 patient's blasts contained cytoplasmic Auer rods. The circulating blasts from another patient expressed MPO while maintaining the same surface phenotype during 20 months of clinical follow-up. In addition, the blasts from 3 cases demonstrated both myelomonocytic and monocyte-specific surface antigens, whereas the remaining 9 cases completely lacked any monocyte-specific antigen detectable by monoclonal antibodies, Mo2, My4 and Leu M3 (CD 14). The first case eventually was diagnosed as acute myelomonocytic leukemia and the second as acute myelogenous leukemia by means of immunophenotypic analysis using flow cytometry (FACS IV). In addition, the presence of MPO protein was identified in the cytoplasm of blast cells from 5 patients with AUL by means of a cytoplasmic immunofluorescence test using a monoclonal antibody (MA1). Our study indicates that non-T, non-B AUL expressing OKM1 (CD 11) antigens include acute leukemias which are unequivocally identifiable as being of either myeloid or myelomonocytic origin. However, further investigations, including immunophenotypic and cytoplasmic analysis, ultrastructural cytochemistry and gene analysis with molecular probes (tests applicable to normal myeloid cells), are necessary in order to determine the actual origin of blasts and to recognize the differentiation stages of the various types of leukemic cells from patients with undifferentiated forms of leukemia.

  12. Apparent feline leukemia virus-induced chronic lymphocytic leukemia and response to treatment.

    Science.gov (United States)

    Kyle, Kristy N; Wright, Zachary

    2010-04-01

    Chylothorax secondary to chronic lymphocytic leukemia (CLL) was diagnosed in a feline leukemia virus (FeLV)-positive 8-year-old castrated male domestic shorthair feline. The leukemia resolved following therapy with chlorambucil, prednisone, cyclophosphamide, doxorubicin, and lomustine. To our knowledge, this is the first reported case of CLL in an FeLV-positive cat. Although a causative relationship cannot be proven, patients diagnosed with either disease may benefit from diagnostics to rule out the presence of the other concurrent condition. Copyright 2009 ISFM and AAFP. Published by Elsevier Ltd. All rights reserved.

  13. Application of a sepharose bead immunofluorescence assay and a solid-phase radioimmunoassay to the bovine leukemia virus system

    International Nuclear Information System (INIS)

    Fiebach, H.; Uckert, W.; Micheel, B.

    1982-01-01

    Several fluorescence assays with bovine leukemia virus (BLV) conjugated to activated Sepharose 4B were used for the detection of BLV and anti-BLV antibodies. These tests were compared with a solid-phase radioimmunoassay and found to be in the same sensitivity range. Sepharose bead immunofluorescence assay and solid-phase radioimmunoassay can be applied to the diagnosis of BLV infection in cattle. (author)

  14. Application of a sepharose bead immunofluorescence assay and a solid-phase radioimmunoassay to the bovine leukemia virus system

    Energy Technology Data Exchange (ETDEWEB)

    Fiebach, H.; Uckert, W.; Micheel, B. (Akademie der Wissenschaften der DDR, Berlin. Zentralinstitut fuer Krebsforschung)

    Several fluorescence assays with bovine leukemia virus (BLV) conjugated to activated Sepharose 4B were used for the detection of BLV and anti-BLV antibodies. These tests were compared with a solid-phase radioimmunoassay and found to be in the same sensitivity range. Sepharose bead immunofluorescence assay and solid-phase radioimmunoassay can be applied to the diagnosis of BLV infection in cattle.

  15. PREVALENCE OF BOVINE HERPESVIRUS-1,PARAINFLUENZA-3,BOVINE ROTAVIRUS, BOVINE VIRAL DIARRHEA, BOVINE ADENOVIRUS-7,BOVINE LEUKEMIA VIRUS AND BLUETONGUE VIRUS ANTIBODIES IN CATTLE IN MEXICO

    OpenAIRE

    SUZAN, Victor M.; ONUMA, Misao; AGUILAR, Romero E.; MURAKAMI, Yosuke

    1983-01-01

    Sera were collected from dairy and beef cattle in 19 different states of Mexico. These sera were tested for bovine herpesvirus-1 (BHV-1), parainfluenza-3 virus (PIV-3), bovine rotavirus (BRV), bovine leukemia virus (BLV), bovine adenovirus-7 (BAV-7), bluetongue virus (BTV) and bovine viral diarrhea virus (BVDV). Seropositive rates for each virus for dairy cattle tested were 158/277(57.0%) for BHV-1,217/286(75.0%) for PIV-3,541/1498(36.1%) for BLV, 134/144(93.1%) for BRV, 39/90(43.3%) for BTV,...

  16. Transient virus expression during murine leukemia induction by x-irradiation

    International Nuclear Information System (INIS)

    Haas, M.

    1977-01-01

    Most x-irradiation-induced thymomas in C57BL/6 mice are virus-free when assayed by immunofluorescence for the gs antigen (gsa) of murine leukemia virus (MuLV). Virus was induced transiently in bone marrow cells and later appeared in thymus cells. Six to 7 weeks post irradiation, thymocytes and bone marrow cells were MuLV gsa-negative and remained negative for the lifetime of most animals, whether or not they contracted overt leukemia. During the period when MuLV gsa-positive bone marrow cells were found, XC-positive syncytia-producing bone marrow cells were also found. Virus information was expressed, therefore, for a limited duration, long before any signs of leukemia in the animal were evident. MuLV gsa-positive thymocytes taken from mice 4 weeks after x-irradiation were cocultivated with a series of indicator cells. B-tropic virus, in addition to a xenotropic virus, was isolated from these cells. Ecotropic virus was not found in normal mouse thymocytes, in irradiated thymocytes a few days after termination of the X-irradiation sequence, or in most primary thymomas. All thymocytes produced only xenotropic virus in the cocultivation assays. Expression of the ecotropic virus was, therefore, transient, as assayed by immunofluorescence, XC syncytia formation, and virus isolation from MuLV gsa-positive thymus cells

  17. Prevalence of antibodies to feline parvovirus, calicivirus, herpesvirus, coronavirus, and immunodeficiency virus and of feline leukemia virus antigen and the interrelationship of these viral infections in free-ranging lions in east Africa.

    Science.gov (United States)

    Hofmann-Lehmann, R; Fehr, D; Grob, M; Elgizoli, M; Packer, C; Martenson, J S; O'Brien, S J; Lutz, H

    1996-09-01

    While viral infections and their impact are well studied in domestic cats, only limited information is available on their occurrence in free-ranging lions. The goals of the present study were (i) to investigate the prevalence of antibodies to feline calicivirus (FCV), herpesvirus (FHV), coronavirus (FCoV), parvovirus (FPV), and immunodeficiency virus (FIV) and of feline leukemia virus (FeLV) antigen in 311 serum samples collected between 1984 and 1991 from lions inhabiting Tanzania's national parks and (ii) to evaluate the possible biological importance and the interrelationship of these viral infections. Antibodies to FCV, never reported previously in free-ranging lions, were detected in 70% of the sera. In addition, a much higher prevalence of antibodies to FCoV (57%) was found than was previously reported in Etosha National Park and Kruger National Park. Titers ranged from 25 to 400. FeLV antigen was not detectable in any of the serum samples. FCoV, FCV, FHV, and FIV were endemic in the Serengeti, while a transient elevation of FPV titers pointed to an outbreak of FPV infection between 1985 and 1987. Antibody titers to FPV and FCV were highly prevalent in the Serengeti (FPV, 75%; FCV, 67%) but not in Ngorongoro Crater (FPV, 27%; FCV, 2%). These differences could be explained by the different habitats and biological histories of the two populations and by the well-documented absence of immigration of lions from the Serengeti plains into Ngorongoro Crater after 1965. These observations indicate that, although the pathological potential of these viral infections seemed not to be very high in free-ranging lions, relocation of seropositive animals by humans to seronegative lion populations must be considered very carefully.

  18. Seroprevalence of feline leukemia virus, feline immunodeficiency virus and heartworm infection among owned cats in tropical Mexico.

    Science.gov (United States)

    Ortega-Pacheco, Antonio; Aguilar-Caballero, Armando J; Colin-Flores, Rafael F; Acosta-Viana, Karla Y; Guzman-Marin, Eugenia; Jimenez-Coello, Matilde

    2014-06-01

    Several infectious agents may be distributed within a healthy population of cats where diverse risk factors predispose them to come into contact with pathogens. Blood samples from 227 owned cats in Merida, Mexico, were collected with the objective of determining the seroprevalence and associated risk factors of feline leukemia virus (FeLV) and Dirofilaria immitis antigen, and feline immunodeficiency virus (FIV) antibody. Serological detection of FeLV and D immitis antigens, and FIV antibodies was performed using the commercial kit SNAP Feline Triple Test. The prevalence was found to be 7.5% for FeLV, 2.5% for FIV and 0% for D immitis. Adult cats were at a higher risk of coming into contact with FeLV (P <0.01) than younger cats. Owing to its low prevalence, a risk factor analysis was not performed for FIV. The prevalence of retroviral infections found in this study was low, but within the limits reported in the different geographical areas of the world. Cases of filariosis in the domestic cats of Merida, Mexico, may be absent or very low; however, the low sample size may have influenced these results. © ISFM and AAFP 2013.

  19. Biochemical analysis of murine leukemia viruses isolated from radiation-induced leukemias of strain BALB/c

    International Nuclear Information System (INIS)

    Ellis, R.W.; Hopkins, N.; Fleissner, E.

    1980-01-01

    Murine leukemia viruses isolated from radiation-induced BALB/c leukemias were characterized with respect to viral proteins and RNA. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the viral structural proteins revealed that for p12, p15, p30, and gp70, three to four electrophoretic variants of each could be detected. There was no correlation found between any of these mobilities and N- or B-tropism of the viruses. Proteins of all xenotropic viral isolates were identical in their gel electrophoretic profiles. The similar phenotypes of multiple viral clones from individual leukemias and of isolates grown in different cells suggest that the polymorphism of ecotropic viruses was generated in vivo rather than during in vitro virus growth. By two-dimensional fingerprinting of RNase T1-resistant oligonucleotides from 70S viral RNA, the previously reported association of N- and B-tropism with two distinct oligonucleotides was confirmed. The presence of two other oligonucleotides was correlated with positive and negative phenotypes of the virus-coded G/sub IX/ cell surface antigen. The RNAs of two B-tropic isolates with distinctive p15 and p12 phenotypes differed from the RNA of a prototype N-tropic virus by the absence of three oligonucleotides mapping in the 5' portion (gag region) of the prototype RNA. In addition, one small-plaque B-tropic virus displayed extensive changes in the RNA sequences associated with the env region of the prototype

  20. Ecotropic murine leukemia virus-induced fusion of murine cells

    International Nuclear Information System (INIS)

    Pinter, A.; Chen, T.; Lowy, A.; Cortez, N.G.; Silagi, S.

    1986-01-01

    Extensive fusion occurs upon cocultivation of murine fibroblasts producing ecotropic murine leukemia viruses (MuLVs) with a large variety of murine cell lines in the presence of the polyene antibiotic amphotericin B, the active component of the antifungal agent Fungizone. The resulting polykaryocytes contain nuclei from both infected and uninfected cells, as evidenced by autoradiographic labeling experiments in which one or the other parent cell type was separately labeled with [ 3 H]thymidine and fused with an unlabeled parent. This cell fusion specifically requires the presence of an ecotropic MuLV-producing parent and is not observed for cells producing xenotropic, amphotropic, or dualtropic viruses. Mouse cells infected with nonecotropic viruses retain their sensitivity toward fusion, whereas infection with ecotropic viruses abrogates the fusion of these cells upon cocultivation with other ecotropic MuLV-producing cells. Nonmurine cells lacking the ecotropic gp70 receptor are not fused under similar conditions. Fusion is effectively inhibited by monospecific antisera to gp70, but not by antisera to p15(E), and studies with monoclonal antibodies identify distinct amino- and carboxy-terminal gp70 regions which play a role in the fusion reaction. The enhanced fusion which occurs in the presence of amphotericin B provides a rapid and sensitive assay for the expression of ecotropic MuLVs and should facilitate further mechanistic studies of MuLV-induced fusion of murine cells

  1. Lack of Durable Cross-Neutralizing Antibodies Against Zika Virus from Dengue Virus Infection.

    Science.gov (United States)

    Collins, Matthew H; McGowan, Eileen; Jadi, Ramesh; Young, Ellen; Lopez, Cesar A; Baric, Ralph S; Lazear, Helen M; de Silva, Aravinda M

    2017-05-01

    Cross-reactive antibodies elicited by dengue virus (DENV) infection might affect Zika virus infection and confound serologic tests. Recent data demonstrate neutralization of Zika virus by monoclonal antibodies or human serum collected early after DENV infection. Whether this finding is true in late DENV convalescence (>6 months after infection) is unknown. We studied late convalescent serum samples from persons with prior DENV or Zika virus exposure. Despite extensive cross-reactivity in IgG binding, Zika virus neutralization was not observed among primary DENV infections. We observed low-frequency (23%) Zika virus cross-neutralization in repeat DENV infections. DENV-immune persons who had Zika virus as a secondary infection had distinct populations of antibodies that neutralized DENVs and Zika virus, as shown by DENV-reactive antibody depletion experiments. These data suggest that most DENV infections do not induce durable, high-level Zika virus cross-neutralizing antibodies. Zika virus-specific antibody populations develop after Zika virus infection irrespective of prior DENV immunity.

  2. Prevalence of feline leukemia virus infection in domestic cats in Rio de Janeiro.

    Science.gov (United States)

    de Almeida, Nadia R; Danelli, Maria G M; da Silva, Lucia H P; Hagiwara, Mitika K; Mazur, Carlos

    2012-08-01

    Peripheral blood smears of 1094 domestic cats were collected and tested by indirect immunofluorescence antibody assay for p27 antigen in cells to study the prevalence and risk factors for feline leukemia virus (FeLV) in the state of Rio de Janeiro. Sex, age, breed, outdoor access, neutering status, type of habitation (household, shelter, veterinary clinics and other places), number of household cats and clinical signs were registered on a form. Among the tested samples, 11.52% were positive. Risk factors for FeLV infection included outdoor access, age range between 1 and 5 years old, and cohabitation with numerous cats.

  3. IGHV1-69 B cell chronic lymphocytic leukemia antibodies cross-react with HIV-1 and hepatitis C virus antigens as well as intestinal commensal bacteria.

    Directory of Open Access Journals (Sweden)

    Kwan-Ki Hwang

    Full Text Available B-cell chronic lymphocytic leukemia (B-CLL patients expressing unmutated immunoglobulin heavy variable regions (IGHVs use the IGHV1-69 B cell receptor (BCR in 25% of cases. Since HIV-1 envelope gp41 antibodies also frequently use IGHV1-69 gene segments, we hypothesized that IGHV1-69 B-CLL precursors may contribute to the gp41 B cell response during HIV-1 infection. To test this hypothesis, we rescued 5 IGHV1-69 unmutated antibodies as heterohybridoma IgM paraproteins and as recombinant IgG1 antibodies from B-CLL patients, determined their antigenic specificities and analyzed BCR sequences. IGHV1-69 B-CLL antibodies were enriched for reactivity with HIV-1 envelope gp41, influenza, hepatitis C virus E2 protein and intestinal commensal bacteria. These IGHV1-69 B-CLL antibodies preferentially used IGHD3 and IGHJ6 gene segments and had long heavy chain complementary determining region 3s (HCDR3s (≥21 aa. IGHV1-69 B-CLL BCRs exhibited a phenylalanine at position 54 (F54 of the HCDR2 as do rare HIV-1 gp41 and influenza hemagglutinin stem neutralizing antibodies, while IGHV1-69 gp41 antibodies induced by HIV-1 infection predominantly used leucine (L54 allelic variants. These results demonstrate that the B-CLL cell population is an expansion of members of the innate polyreactive B cell repertoire with reactivity to a number of infectious agent antigens including intestinal commensal bacteria. The B-CLL IGHV1-69 B cell usage of F54 allelic variants strongly suggests that IGHV1-69 B-CLL gp41 antibodies derive from a restricted B cell pool that also produces rare HIV-1 gp41 and influenza hemagglutinin stem antibodies.

  4. Detection of adult T-cell leukemia virus (ATLV) bearing lymphocytes in concentrated red blood cells derived from ATL associated antibody (ATLA-Ab) positive donors.

    Science.gov (United States)

    Morishima, Y; Ohya, K; Ueda, R; Fukuda, T

    1986-01-01

    Adult T cell leukemia associated antibody (ATLA-Ab) positive persons were screened by indirect immunofluorescence (IF) testing. Their lymphocytes were collected from concentrated red blood cells (CRC), and cultured in vitro with and without phytohemagglutinin (PHA) for 10 days. The expression of ATL virus (ATLV) positive lymphocytes during the in vitro culture was then analyzed by IF assay using mouse monoclonal antibody ATL-19 reactive to p19 core protein of ATLV. 97% of ATLA-Ab positive CRC (36 cases) demonstrated ATLV positive lymphocytes after being cultured for more than 10 days with PHA, whereas, none of ATLA-Ab negative CRC (22 cases) demonstrated ATLV positive lymphocytes. All of the 10 ATLA-Ab positive CRC that were stored for 2, 4, and 7 days contained lymphocytes which expressed ATLV after in vitro culture, while 7 of 10 CRC stored for 14 days and only 1 of 10 CRCs stored for 20 days, expressed ATLV positive lymphocytes. This data indicates that almost all of the ATLA-Ab positive blood contained ATLV positive lymphocytes, and that the in vitro appearance of these ATLV positive lymphocytes was reduced by storing the CRC for more than 14 days.

  5. Biting back: BiTE antibodies as a promising therapy for acute myeloid leukemia.

    Science.gov (United States)

    Walter, Roland B

    2014-06-01

    The experience with gemtuzumab ozogamicin has highlighted both the potential value and limitations of antibodies in acute myeloid leukemia (AML). Recently, bispecific T-cell engager (BiTE) antibodies have emerged as a means to harness polyclonal cytotoxic T-cells and cause highly efficient lysis of targeted tumor cells. Promising early results have been obtained with the CD19-directed BiTE antibody, blinatumomab, in patients with acute lymphoblastic leukemia. A first candidate for AML is the CD33/CD3 molecule, AMG 330, for which several recent preclinical studies demonstrated high potency and efficacy in destroying CD33(+) human AML cells. Many questions remain to be addressed, but BiTE antibodies may offer an exciting new tool in a disease for which the outcomes in many patients remain unsatisfactory.

  6. Cell surface antigens of radiation leukemia virus-induced BALB/c leukemias defined by syngeneic cytotoxic T lymphocytes

    International Nuclear Information System (INIS)

    Kaneko, Yukio; Oettgen, H.F.; Obata, Yuichi; Nakayama, Eiichi.

    1989-01-01

    Two cell surface antigens of mouse leukemias were defined by BALB/c cytotoxic T lymphocytes (CTL) generated against syngeneic radiation leukemia virus (RadLV)-induced leukemia, BALBRV1 or BALBRVD. Hyperimmunization of BALB/c mice with irradiated leukemias followed by in vitro sensitization of primed spleen cells resulted in the generation of CTL with high killing activity. The specificity of CTL was examined by direct cytotoxicity assays and competitive inhibition assays. A shared cell surface antigen, designated as BALBRV1 antigen, was detected by BALB/c anti-BALBRV1 CTL. BALBRV1 antigen was expressed not only on RadLV-induced BALB/c leukemias except for BALBRVD, but also on spontaneous or X-ray-induced BALB/c leukemias, chemically-induced leukemias with the H-2 d haplotype and some chemically-induced BALB/c sarcomas. In contrast, a unique cell surface antigen, designated as BALBRVD antigen, was detected by BALB/c anti-BALBRVD CTL. BALBRVD antigen was expressed only on BALBRVD, but not on thirty-nine normal lymphoid or tumor cells. These two antigens could be distinguished from those previously defined on Friend, Moloney, Rauscher or Gross murine leukemia virus (MuLV) leukemias, or MuLV-related antigens. Both cytotoxic responses were blocked by antisera against H-2K d , but not H-2D d . The relationship of BALBRV1 antigen and BALBRVD antigen to endogenous MuLV is discussed with regard to the antigenic distribution on tumor cell lines. (author)

  7. Development and Characterization of Canine Distemper Virus Monoclonal Antibodies.

    Science.gov (United States)

    Liu, Yuxiu; Hao, Liying; Li, Xiangdong; Wang, Linxiao; Zhang, Jianpo; Deng, Junhua; Tian, Kegong

    2017-06-01

    Five canine distemper virus monoclonal antibodies were developed by immunizing BALB/c mice with a traditional vaccine strain Snyder Hill. Among these monoclonal antibodies, four antibodies recognized both field and vaccine strains of canine distemper virus without neutralizing ability. One monoclonal antibody, 1A4, against hemagglutinin protein of canine distemper virus was found to react only with vaccine strain virus but not field isolates, and showed neutralizing activity to vaccine strain virus. These monoclonal antibodies could be very useful tools in the study of the pathogenesis of canine distemper virus and the development of diagnostic reagents.

  8. Human T cell leukemia virus reactivation with progression of adult T-cell leukemia-lymphoma.

    Directory of Open Access Journals (Sweden)

    Lee Ratner

    Full Text Available Human T-cell leukemia virus-associated adult T-cell leukemia-lymphoma (ATLL has a very poor prognosis, despite trials of a variety of different treatment regimens. Virus expression has been reported to be limited or absent when ATLL is diagnosed, and this has suggested that secondary genetic or epigenetic changes are important in disease pathogenesis.We prospectively investigated combination chemotherapy followed by antiretroviral therapy for this disorder. Nineteen patients were prospectively enrolled between 2002 and 2006 at five medical centers in a phase II clinical trial of infusional chemotherapy with etoposide, doxorubicin, and vincristine, daily prednisone, and bolus cyclophosphamide (EPOCH given for two to six cycles until maximal clinical response, and followed by antiviral therapy with daily zidovudine, lamivudine, and alpha interferon-2a for up to one year. Seven patients were on study for less than one month due to progressive disease or chemotherapy toxicity. Eleven patients achieved an objective response with median duration of response of thirteen months, and two complete remissions. During chemotherapy induction, viral RNA expression increased (median 190-fold, and virus replication occurred, coincident with development of disease progression.EPOCH chemotherapy followed by antiretroviral therapy is an active therapeutic regimen for adult T-cell leukemia-lymphoma, but viral reactivation during induction chemotherapy may contribute to treatment failure. Alternative therapies are sorely needed in this disease that simultaneously prevent virus expression, and are cytocidal for malignant cells.

  9. Role of complement and antibodies in controlling infection with pathogenic simian immunodeficiency virus (SIV in macaques vaccinated with replication-deficient viral vectors

    Directory of Open Access Journals (Sweden)

    Strasak Alexander

    2009-06-01

    Full Text Available Abstract Background We investigated the interplay between complement and antibodies upon priming with single-cycle replicating viral vectors (SCIV encoding SIV antigens combined with Adeno5-SIV or SCIV pseudotyped with murine leukemia virus envelope boosting strategies. The vaccine was applied via spray-immunization to the tonsils of rhesus macaques and compared with systemic regimens. Results Independent of the application regimen or route, viral loads were significantly reduced after challenge with SIVmac239 (p Conclusion The heterologous prime-boost strategy with replication-deficient viral vectors administered exclusively via the tonsils did not induce any neutralizing antibodies before challenge. However, after challenge, comparable SIV-specific humoral immune responses were observed in all vaccinated animals. Immunization with single cycle immunodeficiency viruses mounts humoral immune responses comparable to live-attenuated immunodeficiency virus vaccines.

  10. Differential Susceptibility of Spleen Focus-Forming Virus and Murine Leukemia Viruses to Ansamycin Antibiotics

    Science.gov (United States)

    Horoszewicz, Julius S.; Leong, Susan S.; Carter, William A.

    1977-01-01

    The streptovaricin complex (SvCx) and rifamycin SV derivatives display potent antiviral activity against the polycythemic strain of Friend leukemia virus (FV-P), as measured by a reduction in the number of spleen foci produced in mice. Such reductions may be explained by inactivation of functions of (i) the spleen focus-forming virus (SFFV), (ii) its “helper” murine leukemia virus (MuLV), or (iii) both viruses normally present in FV-P. We noted that preincubation of FV-P with fractionation products of SvCx, or derivatives of rifamycin SV, at low concentrations (3 to 5 μg/ml) reduces the number of spleen foci 80 to 97%, whereas titers of MuLV (from the same inoculum) remain unaffected (MuLV titers were measured by XC, S+L−, and “helper activity” assays). Our findings indicate a remarkable biological selectivity of ansamycins, as well as nonansamycin components of SvCx, against the transforming and defective spleen focus-forming virus as compared to MuLV. Thus, the drugs might be useful in distinguishing other types of oncornaviruses. PMID:18986

  11. Seroprevalence and correlates of human T-cell lymphoma/leukemia virus type 1 antibodies among pregnant women at the University of Nigeria Teaching Hospital, Enugu, Nigeria

    Directory of Open Access Journals (Sweden)

    Okoye AE

    2014-09-01

    Full Text Available Augustine Ejike Okoye,1 Obike Godswill Ibegbulam,2 Robinson Chukwudi Onoh,3 Paul Olisaemeka Ezeonu,3 Ngozi I Ugwu,1 Lucky Osaheni Lawani,3 Chukwudi Simon Anigbo,2 Charles E Nonyelu21Department of Haematology and Immunology, Federal Teaching Hospital, Abakaliki, 2Department of Haematology and Immunology, University of Nigeria Teaching Hospital (UNTH, Ituku-Ozalla, 3Department of Obstetrics and Gynaecology, Federal Teaching Hospital, Abakaliki, NigeriaBackground: Human T-cell lymphoma/leukemia virus (HTLV-1 is a retrovirus transmitted vertically from mother to child parenterally and sexually by infected lymphocytes.Objective: The objective of this study was to determine the seroprevalence of HTLV-1 antibodies and associated risk factors for HTLV-1 infection among pregnant women in University of Nigeria Teaching Hospital, Enugu, southeast Nigeria.Materials and methods: A cross-sectional study was carried out from July to October 2010. Two hundred pregnant women were recruited consecutively from the antenatal clinic. Five milliliters of blood was collected from each of the participants into a plain sterile bottle and allowed to clot. The serum obtained was stored at -20°C until required for analysis. The serum samples were then analyzed for antibodies to HTLV-1 using a one-step incubation double-antigen sandwich enzyme-linked immunosorbent assay kit. Participants' demographic characteristics and degree of exposure to the risk factors associated with HTLV-1 infection were captured using a questionnaire. Statistical analysis of results was done using SPSS version 17.Results: The average age of the pregnant women was 28.94 years (standard deviation 4.17. The age-group with the highest representation was those between the ages of 26 and 30 years. Thirty-six percent of the population was above 30 years old. The result of the tests showed that only one respondent, a 31-year-old pregnant woman tested positive for HTLV-1 antibodies. Therefore, the

  12. Single Amino Acid Insertion in Loop 4 Confers Amphotropic Murine Leukemia Virus Receptor Function upon Murine Pit1

    DEFF Research Database (Denmark)

    Lundorf, Mikkel D.; Pedersen, Finn Skou; O'Hara, Bryan

    1998-01-01

    Pit1 is the human receptor for gibbon ape leukemia virus (GALV) and feline leukemia virus subgroup B (FeLV-B), while the related human protein Pit2 is a receptor for amphotropic murine leukemia virus (A-MuLV). The A-MuLV-related isolate 10A1 can utilize both Pit1 and Pit2 as receptors. A stretch...

  13. Properties of murine leukemia viruses produced by leukemic cells established from NIH Swiss mice with radiation-induced leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Okumoto, Masaaki; Nishikawa, Ryosuke; Takamori, Yasuhiko; Iwai, Yoshiaki; Iwai, Mineko [Radiation Center of Osaka Prefecture, Sakai (Japan); Imai, Shunsuke; Morimoto, Junji; Tsubura, Yoshihiko

    1984-06-01

    Three leukemic cell lines, designated NIH-RL1, NIH-RL2 and NFS-RL1, were established from spleen and thymuses of NIH Swiss and NFS mice with radiation-induced leukemia. The culture fluids of these cell lines contained RNA-dependent DNA polymerase (RDDP) activities associated with particles of buoyant density of 1.15-1.17 (g/cm/sup 3/). The divalent cation reqirement of these enzymes was characteristic for that of murine leukemia viruses. In competition radioimmunoassay, a major core protein, p30, was detected in culture fluid of each leukemic cell line. Competition curves of viral p30 produced by these cell lines revealed that these viruses were very similar to those of xenotropic viruses of NZB mice. These viruses were undetectable both by XC plaque assay using SC-1 cells as an indicator cell, and by mink S/sup +/L/sup -/ focus induction assay. These viruses also lacked productive infectivity to mink lung cells (CCL-64), and were nononcogenic in syngeneic mice when the viruses were intrathymically inoculated.

  14. Vaccine induced antibodies to the first variable loop of human immunodeficiency virus type 1 gp120, mediate antibody-dependent virus inhibition in macaques.

    Science.gov (United States)

    Bialuk, Izabela; Whitney, Stephen; Andresen, Vibeke; Florese, Ruth H; Nacsa, Janos; Cecchinato, Valentina; Valeri, Valerio W; Heraud, Jean-Michel; Gordon, Shari; Parks, Robyn Washington; Montefiori, David C; Venzon, David; Demberg, Thorsten; Guroff, Marjorie Robert-; Landucci, Gary; Forthal, Donald N; Franchini, Genoveffa

    2011-12-09

    The role of antibodies directed against the hyper variable envelope region V1 of human immunodeficiency virus type 1 (HIV-1), has not been thoroughly studied. We show that a vaccine able to elicit strain-specific non-neutralizing antibodies to this region of gp120 is associated with control of highly pathogenic chimeric SHIV(89.6P) replication in rhesus macaques. The vaccinated animal that had the highest titers of antibodies to the amino terminus portion of V1, prior to challenge, had secondary antibody responses that mediated cell killing by antibody-dependent cellular cytotoxicity (ADCC), as early as 2 weeks after infection and inhibited viral replication by antibody-dependent cell-mediated virus inhibition (ADCVI), by 4 weeks after infection. There was a significant inverse correlation between virus level and binding antibody titers to the envelope protein, (R=-0.83, p=0.015), and ADCVI (R=-0.84 p=0.044). Genotyping of plasma virus demonstrated in vivo selection of three SHIV(89.6P) variants with changes in potential N-linked glycosylation sites in V1. We found a significant inverse correlation between virus levels and titers of antibodies that mediated ADCVI against all the identified V1 virus variants. A significant inverse correlation was also found between neutralizing antibody titers to SHIV(89.6) and virus levels (R=-0.72 p=0.0050). However, passive inoculation of purified immunoglobulin from animal M316, the macaque that best controlled virus, to a naïve macaque, resulted in a low serum neutralizing antibodies and low ADCVI activity that failed to protect from SHIV(89.6P) challenge. Collectively, while our data suggest that anti-envelope antibodies with neutralizing and non-neutralizing Fc(R-dependent activities may be important in the control of SHIV replication, they also demonstrate that low levels of these antibodies alone are not sufficient to protect from infection. Published by Elsevier Ltd.

  15. Mutations that abrogate transactivational activity of the feline leukemia virus long terminal repeat do not affect virus replication

    International Nuclear Information System (INIS)

    Abujamra, Ana L.; Faller, Douglas V.; Ghosh, Sajal K.

    2003-01-01

    The U3 region of the LTR of oncogenic Moloney murine leukemia virus (Mo-MuLV) and feline leukemia viruses (FeLV) have been previously reported to activate expression of specific cellular genes in trans, such as MHC class I, collagenase IV, and MCP-1, in an integration-independent manner. It has been suggested that transactivation of these specific cellular genes by leukemia virus U3-LTR may contribute to the multistage process of leukemogenesis. The U3-LTR region, necessary for gene transactivational activity, also contains multiple transcription factor-binding sites that are essential for normal virus replication. To dissect the promoter activity and the gene transactivational activity of the U3-LTR, we conducted mutational analysis of the U3-LTR region of FeLV-A molecular clone 61E. We identified minimal nucleotide substitution mutants on the U3 LTR that did not disturb transcription factor-binding sites but abrogated its ability to transactivate the collagenase gene promoter. To determine if these mutations actually have altered any uncharacterized important transcription factor-binding site, we introduced these U3-LTR mutations into the full-length infectious molecular clone 61E. We demonstrate that the mutant virus was replication competent but could not transactivate cellular gene expression. These results thus suggest that the gene transactivational activity is a distinct property of the LTR and possibly not related to its promoter activity. The cellular gene transactivational activity-deficient mutant FeLV generated in this study may also serve as a valuable reagent for testing the biological significance of LTR-mediated cellular gene activation in the tumorigenesis caused by leukemia viruses

  16. Antibody escape kinetics of equine infectious anemia virus infection of horses.

    Science.gov (United States)

    Schwartz, Elissa J; Nanda, Seema; Mealey, Robert H

    2015-07-01

    Lentivirus escape from neutralizing antibodies (NAbs) is not well understood. In this work, we quantified antibody escape of a lentivirus, using antibody escape data from horses infected with equine infectious anemia virus. We calculated antibody blocking rates of wild-type virus, fitness costs of mutant virus, and growth rates of both viruses. These quantitative kinetic estimates of antibody escape are important for understanding lentiviral control by antibody neutralization and in developing NAb-eliciting vaccine strategies. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  17. De novo design of peptide immunogens that mimic the coiled coil region of human T-cell leukemia virus type-1 glycoprotein 21 transmembrane subunit for induction of native protein reactive neutralizing antibodies.

    Science.gov (United States)

    Sundaram, Roshni; Lynch, Marcus P; Rawale, Sharad V; Sun, Yiping; Kazanji, Mirdad; Kaumaya, Pravin T P

    2004-06-04

    Peptide vaccines able to induce high affinity and protective neutralizing antibodies must rely in part on the design of antigenic epitopes that mimic the three-dimensional structure of the corresponding region in the native protein. We describe the design, structural characterization, immunogenicity, and neutralizing potential of antibodies elicited by conformational peptides derived from the human T-cell leukemia virus type 1 (HTLV-1) gp21 envelope glycoprotein spanning residues 347-374. We used a novel template design and a unique synthetic approach to construct two peptides (WCCR2T and CCR2T) that would each assemble into a triple helical coiled coil conformation mimicking the gp21 crystal structure. The peptide B-cell epitopes were grafted onto the epsilon side chains of three lysyl residues on a template backbone construct consisting of the sequence acetyl-XGKGKGKGCONH2 (where X represents the tetanus toxoid promiscuous T cell epitope (TT) sequence 580-599). Leucine substitutions were introduced at the a and d positions of the CCR2T sequence to maximize helical character and stability as shown by circular dichroism and guanidinium hydrochloride studies. Serum from an HTLV-1-infected patient was able to recognize the selected epitopes by enzyme-linked immunosorbent assay (ELISA). Mice immunized with the wild-type sequence (WCCR2T) and the mutant sequence (CCR2T) elicited high antibody titers that were capable of recognizing the native protein as shown by flow cytometry and whole virus ELISA. Sera and purified antibodies from immunized mice were able to reduce the formation of syncytia induced by the envelope glycoprotein of HTLV-1, suggesting that antibodies directed against the coiled coil region of gp21 are capable of disrupting cell-cell fusion. Our results indicate that these peptides represent potential candidates for use in a peptide vaccine against HTLV-1.

  18. Evidence for the replication of bovine leukemia virus in the B lymphocytes

    International Nuclear Information System (INIS)

    Paul, P.S.; Pomeroy, K.A.; Johnson, D.W.; Muscoplat, C.C.; Handwerger, B.S.; Soper, F.F.; Sorensen, D.K.

    1977-01-01

    Bovine peripheral blood lymphocytes from a cow with persistent lymphocytosis were separated on nylon wool columns into nylon-adherent and nonadherent populations. Nylon-adherent cells were highly enriched for surface immunoglobulin (SIg) bearing B lymphocytes (95.5%) and nonadherent cells for SIg negative non-B cells, presumably T lymphocytes (96.3%). The B lymphocytes were found to be the major producers for bovine leukemia virus. A total of 39% of the B-enriched cells, surviving after 72 hours in culture, produced bovine leukemia virus as compared with 0.5% of the non-B cells

  19. Virus-neutralizing antibody response of mice to consecutive infection with human and avian influenza A viruses.

    Science.gov (United States)

    Janulíková, J; Stropkovská, A; Bobišová, Z; Košík, I; Mucha, V; Kostolanský, F; Varečková, E

    2015-06-01

    In this work we simulated in a mouse model a naturally occurring situation of humans, who overcame an infection with epidemic strains of influenza A, and were subsequently exposed to avian influenza A viruses (IAV). The antibody response to avian IAV in mice previously infected with human IAV was analyzed. We used two avian IAV (A/Duck/Czechoslovakia/1956 (H4N6) and the attenuated virus rA/Viet Nam/1203-2004 (H5N1)) as well as two human IAV isolates (virus A/Mississippi/1/1985 (H3N2) of medium virulence and A/Puerto Rico/8/1934 (H1N1) of high virulence). Two repeated doses of IAV of H4 or of H5 virus elicited virus-specific neutralizing antibodies in mice. Exposure of animals previously infected with human IAV (of H3 or H1 subtype) to IAV of H4 subtype led to the production of antibodies neutralizing H4 virus in a level comparable with the level of antibodies against the human IAV used for primary infection. In contrast, no measurable levels of virus-neutralizing (VN) antibodies specific to H5 virus were detected in mice infected with H5 virus following a previous infection with human IAV. In both cases the secondary infection with avian IAV led to a significant increase of the titer of VN antibodies specific to the corresponding human virus used for primary infection. Moreover, cross-reactive HA2-specific antibodies were also induced by sequential infection. By virtue of these results we suggest that the differences in the ability of avian IAV to induce specific antibodies inhibiting virus replication after previous infection of mice with human viruses can have an impact on the interspecies transmission and spread of avian IAV in the human population.

  20. Swine Influenza Virus Antibodies in Humans, Western Europe, 2009

    Science.gov (United States)

    Gerloff, Nancy A.; Kremer, Jacques R.; Charpentier, Emilie; Sausy, Aurélie; Olinger, Christophe M.; Weicherding, Pierre; Schuh, John; Van Reeth, Kristien

    2011-01-01

    Serologic studies for swine influenza viruses (SIVs) in humans with occupational exposure to swine have been reported from the Americas but not from Europe. We compared levels of neutralizing antibodies against 3 influenza viruses—pandemic (H1N1) 2009, an avian-like enzootic subtype H1N1 SIV, and a 2007–08 seasonal subtype H1N1—in 211 persons with swine contact and 224 matched controls in Luxembourg. Persons whose profession involved contact with swine had more neutralizing antibodies against SIV and pandemic (H1N1) 2009 virus than did the controls. Controls also had antibodies against these viruses although exposure to them was unlikely. Antibodies against SIV and pandemic (H1N1) 2009 virus correlated with each other but not with seasonal subtype H1N1 virus. Sequential exposure to variants of seasonal influenza (H1N1) viruses may have increased chances for serologic cross-reactivity with antigenically distinct viruses. Further studies are needed to determine the extent to which serologic responses correlate with infection. PMID:21392430

  1. Replacement of Murine Leukemia Virus Readthrough Mechanism by Human Immunodeficiency Virus Frameshift Allows Synthesis of Viral Proteins and Virus Replication

    Science.gov (United States)

    Brunelle, Marie-Noëlle; Brakier-Gingras, Léa; Lemay, Guy

    2003-01-01

    Retroviruses use unusual recoding strategies to synthesize the Gag-Pol polyprotein precursor of viral enzymes. In human immunodeficiency virus, ribosomes translating full-length viral RNA can shift back by 1 nucleotide at a specific site defined by the presence of both a slippery sequence and a downstream stimulatory element made of an extensive secondary structure. This so-called frameshift mechanism could become a target for the development of novel antiviral strategies. A different recoding strategy is used by other retroviruses, such as murine leukemia viruses, to synthesize the Gag-Pol precursor; in this case, a stop codon is suppressed in a readthrough process, again due to the presence of a specific structure adopted by the mRNA. Development of antiframeshift agents will greatly benefit from the availability of a simple animal and virus model. For this purpose, the murine leukemia virus readthrough region was rendered inactive by mutagenesis and the frameshift region of human immunodeficiency virus was inserted to generate a chimeric provirus. This substitution of readthrough by frameshift allows the synthesis of viral proteins, and the chimeric provirus sequence was found to generate infectious viruses. This system could be a most interesting alternative to study ribosomal frameshift in the context of a virus amenable to the use of a simple animal model. PMID:12584361

  2. [Adult T-cell leukemia/lymphoma associated with unusual positivity of anti-ATLA (adult T-cell leukemia-cell-associated antigen) antibodies].

    Science.gov (United States)

    Eto, T; Okamura, H; Okamura, T; Gondo, H; Kudo, J; Shibuya, T; Harada, M; Niho, Y

    1990-03-01

    A 56-year-old female was admitted because of generalized lymphadenopathy. Based upon histological findings of biopsied lymph node, malignant lymphoma, diffuse large cell type was diagnosed. The surface marker analysis showed that malignant cells were positive for CD4 and CD2 but negative for CD8. Although anti-ATLA (adult T-cell leukemia associated antigen) antibody was negative with the use of a gelatin particle agglutination method (P.A.), other methods such as an indirect immunofluorescence assay (I.F.), an enzyme-linked immunosorbent assay (E.I.A.) and a Western blotting assay revealed the positivity for anti-ATLA antibody. Adult T-cell leukemia/lymphoma (ATL/L) was confirmed by the presence of monoclonal integration of HTLV-I proviral DNA in biopsied specimen. This case, showing a pattern of P.A. (-) and I.F. (+), is extremely unusual, because I.F. and P.A. show highly close correlation. Thus, it is important to employ different methods for screening of anti-ATLA antibodies in the diagnosis of ATL/L.

  3. Characterization of Ebola Virus Entry by Using Pseudotyped Viruses: Identification of Receptor-Deficient Cell Lines

    OpenAIRE

    Wool-Lewis, Rouven J.; Bates, Paul

    1998-01-01

    Studies analyzing Ebola virus replication have been severely hampered by the extreme pathogenicity of this virus. To permit analysis of the host range and function of the Ebola virus glycoprotein (Ebo-GP), we have developed a system for pseudotyping these glycoproteins into murine leukemia virus (MLV). This pseudotyped virus, MLV(Ebola), can be readily concentrated to titers which exceed 5 × 106 infectious units/ml and is effectively neutralized by antibodies specific for Ebo-GP. Analysis of ...

  4. Neutralizing antibodies against flaviviruses, Babanki virus, and Rift Valley fever virus in Ugandan bats.

    Science.gov (United States)

    Kading, Rebekah C; Kityo, Robert M; Mossel, Eric C; Borland, Erin M; Nakayiki, Teddie; Nalikka, Betty; Nyakarahuka, Luke; Ledermann, Jeremy P; Panella, Nicholas A; Gilbert, Amy T; Crabtree, Mary B; Peterhans, Julian Kerbis; Towner, Jonathan S; Amman, Brian R; Sealy, Tara K; Nichol, Stuart T; Powers, Ann M; Lutwama, Julius J; Miller, Barry R

    2018-01-01

    Introduction: A number of arboviruses have previously been isolated from naturally-infected East African bats, however the role of bats in arbovirus maintenance is poorly understood. The aim of this study was to investigate the exposure history of Ugandan bats to a panel of arboviruses. Materials and methods: Insectivorous and fruit bats were captured from multiple locations throughout Uganda during 2009 and 2011-2013. All serum samples were tested for neutralizing antibodies against West Nile virus (WNV), yellow fever virus (YFV), dengue 2 virus (DENV-2), Zika virus (ZIKV), Babanki virus (BBKV), and Rift Valley fever virus (RVFV) by plaque reduction neutralization test (PRNT). Sera from up to 626 bats were screened for antibodies against each virus. Results and Discussion:  Key findings include the presence of neutralizing antibodies against RVFV in 5/52 (9.6%) of little epauletted fruit bats ( Epomophorus labiatus ) captured from Kawuku and 3/54 (5.6%) Egyptian rousette bats from Kasokero cave. Antibodies reactive to flaviviruses were widespread across bat taxa and sampling locations. Conclusion: The data presented demonstrate the widespread exposure of bats in Uganda to arboviruses, and highlight particular virus-bat associations that warrant further investigation.

  5. Antibody neutralization of retargeted measles viruses

    Science.gov (United States)

    Lech, Patrycja J.; Pappoe, Roland; Nakamura, Takafumi; Tobin, Gregory J.; Nara, Peter L.; Russell, Stephen J.

    2014-01-01

    The measles virus (MV) vaccine lineage is a promising oncolytic but prior exposure to the measles vaccine or wild-type MV strains limits treatment utility due to the presence of anti-measles antibodies. MV entry can be redirected by displaying a polypeptide ligand on the Hemagglutinin (H) C-terminus. We hypothesized that retargeted MV would escape neutralization by monoclonal antibodies (mAbs) recognizing the H receptor-binding surface and be less susceptible to neutralization by human antisera. Using chimeric H proteins, with and without mutations that ablate MV receptor binding, we show that retargeted MVs escape mAbs that target the H receptor-binding surface by virtue of mutations that ablate infection via SLAM and CD46. However, C-terminally displayed domains do not mediate virus entry in the presence of human antibodies that bind to the underlying H domain. In conclusion, utility of retargeted oncolytic measles viruses does not extend to evasion of human serum neutralization. PMID:24725950

  6. Seroprevalence of Toxoplasma gondii and concurrent bartonella spp., feline immunodeficiency virus, and feline leukemia infections in cats from Grenada, West Indies

    Science.gov (United States)

    Toxoplasma gondii and Bartonella spp. are zoonotic pathogens of cats. Feline Immunodeficiency Virus (FIV), and Feline Leukemia Virus (FeLv) are related to Human Iimmunodeficiency Virus, and Human Leukemia Virus, respectively, and these viruses are immunosuppressive. In the present study, the prevale...

  7. Radioimmunoassay of measles virus antibodies in SSPE

    International Nuclear Information System (INIS)

    Jankowski, M.A.; Gut, W.; Kantoch, M.

    1982-01-01

    A sensitive radioimmunoassay (RIA) was introduced for detecting measles virus IgG and IgM antibodies. The hyperimmune response to the measles virus could be demonstrated more accurately by RIA than by haemagglutination inhibition (HI). The ratio between RIA and HI antibody titres was decidedly higher in sera and cerebrospinal fluids of patients with subacute sclerosing panencephalitis than in those of other groups tested. (author)

  8. INFECTIOUS VIRUS-ANTIBODY COMPLEX IN THE BLOOD OF CHRONICALLY INFECTED MICE

    Science.gov (United States)

    Notkins, Abner Louis; Mahar, Suellen; Scheele, Christina; Goffman, Joel

    1966-01-01

    If viremic sera from mice chronically infected with lactic dehydrogenase virus (LDV) were first treated with ether or ultraviolet light to inactivate the infectious virus, neutralizing antibody could be demonstrated. Significant amounts of antibody, however, were not detected until the mice had been infected for about 2½ months and its presence did not result in the elimination of the chronic viremia. Virus isolated from sera containing neutralizing antibody was found to be relatively resistant to neutralization by anti-LDV. Further studies revealed that the resistant virus existed in the form of an infectious virus-antibody complex (sensitized virus). The presence of such a complex was demonstrated by the fact that the virus fraction which persisted after in vivo or in vitro exposure to mouse anti-LDV was readily neutralized by goat anti-mouse sera or goat anti-mouse γ-globulin, whereas virus that had not been previously exposed to mouse anti-LDV was completely resistant to neutralization by goat anti-mouse sera. These findings suggest that (a) sensitization may play an important role in the resistance and susceptibility of a virus to neutralization by antiviral antibody, and (b) an anti-γ-globulin may prove useful in neutralizing the resistant fraction and in demonstrating otherwise undetectable antiviral antibody. PMID:5944351

  9. The human CD38 monoclonal antibody daratumumab shows antitumor activity and hampers leukemia-microenvironment interactions in chronic lymphocytic leukemia

    DEFF Research Database (Denmark)

    Matas-Céspedes, Alba; Vidal-Crespo, Anna; Rodriguez, Vanina

    2017-01-01

    Purpose: To establish a proof-of-concept for the efficacy of the anti-CD38 antibody daratumumab in the poor prognosis CD38+ chronic lymphocytic leukemia (CLL) subtype. Experimental Design: The mechanism of action of daratumumab was assessed in CLL primary cells and cell lines using peripheral blo...

  10. Differential diagnosis of feline leukemia virus subgroups using pseudotype viruses expressing green fluorescent protein.

    Science.gov (United States)

    Nakamura, Megumi; Sato, Eiji; Miura, Tomoyuki; Baba, Kenji; Shimoda, Tetsuya; Miyazawa, Takayuki

    2010-06-01

    Feline leukemia virus (FeLV) is classified into three receptor interference subgroups, A, B and C. In this study, to differentiate FeLV subgroups, we developed a simple assay system using pseudotype viruses expressing green fluorescent protein (GFP). We prepared gfp pseudotype viruses, named gfp(FeLV-A), gfp(FeLV-B) and gfp(FeLV-C) harboring envelopes of FeLV-A, B and C, respectively. The gfp pseudotype viruses completely interfered with the same subgroups of FeLV reference strains on FEA cells (a feline embryonic fibroblast cell line). We also confirmed that the pseudotype viruses could differentiate FeLV subgroups in field isolates. The assay will be useful for differential diagnosis of FeLV subgroups in veterinary diagnostic laboratories in the future.

  11. Molecular cloning of osteoma-inducing replication-competent murine leukemia viruses from the RFB osteoma virus stock

    DEFF Research Database (Denmark)

    Pedersen, Lene; Behnisch, Werner; Schmidt, Jörg

    1992-01-01

    We report the molecular cloning of two replication-competent osteoma-inducing murine leukemia viruses from the RFB osteoma virus stock (M. P. Finkel, C. A. Reilly, Jr., B. O. Biskis, and I. L. Greco, p. 353-366, in C. H. G. Price and F. G. M. Ross, ed., Bone--Certain Aspects of Neoplasia, 1973......). Like the original RFB osteoma virus stock, viruses derived from the molecular RFB clones induced multiple osteomas in mice of the CBA/Ca strain. The cloned RFB viruses were indistinguishable by restriction enzyme analysis and by nucleotide sequence analysis of their long-terminal-repeat regions...

  12. Feline leukemia virus infection requires a post-receptor binding envelope-dependent cellular component.

    Science.gov (United States)

    Hussain, Naveen; Thickett, Kelly R; Na, Hong; Leung, Cherry; Tailor, Chetankumar S

    2011-12-01

    Gammaretrovirus receptors have been suggested to contain the necessary determinants to mediate virus binding and entry. Here, we show that murine NIH 3T3 and baby hamster kidney (BHK) cells overexpressing receptors for subgroup A, B, and C feline leukemia viruses (FeLVs) are weakly susceptible (10(1) to 10(2) CFU/ml) to FeLV pseudotype viruses containing murine leukemia virus (MLV) core (Gag-Pol) proteins, whereas FeLV receptor-expressing murine Mus dunni tail fibroblast (MDTF) cells are highly susceptible (10(4) to 10(6) CFU/ml). However, NIH 3T3 cells expressing the FeLV subgroup B receptor PiT1 are highly susceptible to gibbon ape leukemia virus pseudotype virus, which differs from the FeLV pseudotype viruses only in the envelope protein. FeLV resistance is not caused by a defect in envelope binding, low receptor expression levels, or N-linked glycosylation. Resistance is not alleviated by substitution of the MLV core in the FeLV pseudotype virus with FeLV core proteins. Interestingly, FeLV resistance is alleviated by fusion of receptor-expressing NIH 3T3 and BHK cells with MDTF or human TE671 cells, suggesting the absence of an additional cellular component in NIH 3T3 and BHK cells that is required for FeLV infection. The putative FeLV-specific cellular component is not a secreted factor, as MDTF conditioned medium does not alleviate the block to FeLV infection. Together, our findings suggest that FeLV infection requires an additional envelope-dependent cellular component that is absent in NIH 3T3 and BHK cells but that is present in MDTF and TE671 cells.

  13. Relevance of feline calicivirus, feline immunodeficiency virus, feline leukemia virus, feline herpesvirus and Bartonella henselae in cats with chronic gingivostomatitis.

    Science.gov (United States)

    Belgard, Sylvia; Truyen, Uwe; Thibault, Jean-Christophe; Sauter-Louis, Carola; Hartmann, Katrin

    2010-01-01

    Despite its common occurrence, the aetiology of chronic gingivostomatitis in cats remains uncertain. Aetiology is likely multifactorial, and several infectious agents may be associated with chronic gingivostomatitis. The purpose of this study was to investigate the prevalence of feline calicivirus (FCV), feline immunodeficiency virus (FIV), feline leukemia virus (FeLV), feline herpesvirus (FHV), and Bartonella henselae (B. henselae) in cats with chronic gingivostomatitis and in an age-matched control group. In addition, other factors, e. g., environmental conditions were investigated. In 52 cats with chronic gingivostomatitis and 50 healthy age-matched control cats, the presence of FCV ribonucleic acid (RNA), and FHV deoxyribonucleic acid (DNA) (polymerase chain reaction [PCR] from oropharyngeal swabs), and B. henselae DNA (PCR from oropharyngeal swabs and blood), as well as FeLV antigen (serum), and antibodies against FCV, B. henselae, and FIV (serum) were examined. FCV RNA was significantly more common in cats with chronic gingivostomatitis (53.8%, p < 0.001) than in controls (14.0%); a significant difference was also found in the prevalence of antibodies to FCV between the cats with chronic gingivostomatitis (78.8%, p = 0.023) and controls (58.0%). Of the other infectious agents investigated, there was no significant difference in the prevalence between the cats with chronic gingivostomatitis and the controls. The results of this study allow the conclusion that FCV, but no other infectious agents, is commonly associated with chronic gingivostomatitis in cats.

  14. Facial nerve ganglioneuroblastoma in a feline leukemia virus-positive cat

    Directory of Open Access Journals (Sweden)

    Paula Reis Pereira

    Full Text Available ABSTRACT: Neuroblastic tumors can originate from the central neuraxis, olfactory epithelium, adrenal medullary region or autonomous system. Ganglioneuroblastoma are a type of neuroblastic tumor, with very few case descriptions in animals. Diagnosis of facial nerve ganglioneuroblastoma was made in a feline leukemia virus-positive 11-month-old cat. The cat had hyporexia, left head tilt, depressed mental state, horizontal nystagmus, inability to retract the pinched left lip, anisocoria, ptosis, and absence of the menace reflex. Gross necropsy showed a mass at the left facial nerve root region. Histological examination of this mass showed neoplastic proliferation of neuroblasts arranged in a cohesive pattern and mature ganglion cells. Ganglion cells were positive for neurofilament, neuron-specific enolase, S100, and glial fibrillary acidic protein by immunohistochemistry, while neuroblasts were positive for vimentin, S100, neuron-specific enolase and feline leukemia virus.

  15. Short communication. Microculture syncytia assay for bovine leukemia virus

    Energy Technology Data Exchange (ETDEWEB)

    Paul, P.S.; Castro, A.E.; Pomeroy, K.A.; Johnson, D.W.; Muscoplat, C.C.

    1978-01-01

    A microculture syncytia assay for the detection of bovine leukemia virus (BLV) has been described and compared with the conventional macroculture assay. The microculture assay required fewer indicator cells, was as sensitive as the macroculture assay and provided a reproducible test for the detection and titration of BLV.

  16. Antibodies to adult T-cell leukemia-virus-associated antigen (ATLA) in sera from patients with ATL and controls in Japan: a nation-wide sero-epidemiologic study.

    Science.gov (United States)

    Hinuma, Y; Komoda, H; Chosa, T; Kondo, T; Kohakura, M; Takenaka, T; Kikuchi, M; Ichimaru, M; Yunoki, K; Sato, I; Matsuo, R; Takiuchi, Y; Uchino, H; Hanaoka, M

    1982-06-15

    A nation-wide sero-epidemiologic survey of adult T-cell leukemia virus (ATLV), detected es anti-ATLA (ATLV-associated antigen), was made in Japan. Sera from adult donors in 15 different locations were screened for anti-ATLA. High incidences (6 to 37%) of antibody-positive donors were found in seven regions, one in northern Japan, and the others in southwestern regions. These areas are ATLV-endemic areas corresponding to ATL-endemic areas. Examination of sera from healthy donors aged 6 to 80 years in ATL-endemic areas showed an age-dependent increase of seropositive donors with a maximum of about 30% at 40 years of age. Anti-ATLA was found in all but two of 142 patients with ATL. Anti-ATLA-positive patients with ATL were mainly found in ATLV-endemic areas, and only a few in ATL-nonendemic areas. Six patients with cutaneous T-cell lymphoma in ATLV-nonendemic areas gave a negative reaction for anti-ATLA. The geometric mean titer of anti-ATLA of patients with ATL was higher than that of healthy donors.

  17. Using a Herd Profile to Determine Age-Specific Prevalence of Bovine Leukemia Virus in Michigan Dairy Herds

    Directory of Open Access Journals (Sweden)

    Ronald J. Erskine

    2012-01-01

    Full Text Available Enzootic bovine leukosis is a contagious disease of cattle caused by the retrovirus, bovine leukemia virus (BLV and is the most common cause of malignant neoplasm in cattle. In order to facilitate surveillance of this disease in dairy herds, we developed a method to combine ELISA of milk collected during routine production testing with a prescribed sampling of cows that is independent of the proportion of cows within each lactation. In 113 Michigan dairy herds, milk samples from ten cows in each of the 1st, 2nd, 3rd, and ≥4th lactations were analyzed for anti-Bovine Leukemia Virus (BLV antibodies by milk ELISA. For each herd, a BLV herd profile (BHP was calculated as the simple average of the percent of BLV-positive cows within each of the four lactation groups. The mean BHP for all herds was 32.8%, with means of 18.5, 28.8, 39.2, and 44.8% of 1st, 2nd, 3rd, and ≥4th lactation animals infected, respectively. In eight herds, we determined the correlation between the BHP, and true herd prevalence by testing the entire lactating herd (r=0.988,  P<0.0001. The BHP allows discrimination of lactation-specific BLV prevalence within a dairy herd, to help identify risk factors and management plans that may be important in transmission of BLV.

  18. Mathematical analysis of dengue virus antibody dynamics

    Science.gov (United States)

    Perera, Sulanie; Perera, SSN

    2018-03-01

    Dengue is a mosquito borne viral disease causing over 390 million infections worldwide per annum. Even though information on how infection is controlled and eradicated from the body is lacking, antibodies are thought to play a major role in clearing the virus. In this paper, a non-linear conceptual dynamical model with humoral immune response and absorption effect has been proposed for primary dengue infection. We have included the absorption of pathogens into uninfected cells since this effect causes the virus density in the blood to decrease. The time delay that arises in the production of antibodies was accounted and is introduced through a continuous function. The basic reproduction number R0 is computed and a detailed stability analysis is done. Three equilibrium states, namely the infection free equilibrium, no immune equilibrium and the endemic equilibrium were identified and the existence and the stability conditions of these steady states were obtained. Numerical simulations proved the results that were obtained. By establishing the characteristic equation of the model at infection free equilibrium, it was observed that the infection free equilibrium is locally asymptotically stable if R0 1. Stability regions are identified for infection free equilibrium state with respect to the external variables and it is observed as the virus burst rate increases, the stability regions would decrease. These results implied that for higher virus burst rates, other conditions in the body must be strong enough to eliminate the disease completely from the host. The effect of time delay of antibody production on virus dynamics is discussed. It was seen that as the time delay in production of antibodies increases, the time for viral decline also increased. Also it was observed that the virus count goes to negligible levels within 7 - 14 days after the onset of symptoms as seen in dengue infections.

  19. Seroprevalence of Marek's Disease Virus antibody in some poultry ...

    African Journals Online (AJOL)

    This study reports a survey of Marek's disease virus (MDV) antibody done in 21 selected poultry flocks in Lagos, Ogun and Oyo states of southwestern Nigeria. A total of 315 serum samples were examined using the Enzyme Linked Immunosorbent Assay (ELISA) technique. Marek's disease virus antibody was present in ...

  20. [Production of monoclonal antibodies against a wild strain of rabies virus].

    Science.gov (United States)

    Akacem, O; Benmansour, A; Coulon, P; Brahimi, M; Benhassine, M

    1992-01-01

    Production of monoclonal antibodies against a wild strain of rabies virus. Cell fusion of SP 2/O, a murine myeloma against a wild strain of rabies virus has originated five monoclonal antibodies (M.A.) specific for virus nucleocapsid , one M.A. specific for virus glycoprotein and one M.A. specific for a viral membrane protein.

  1. Radioimmunoassay for antibodies to rubella virus and its ribonucleoprotein component

    International Nuclear Information System (INIS)

    Ho-Terry, L.; Cohen, A.

    1979-01-01

    Using a radioimmune precipitation technique, the antibody response to intact rubella virus and its ribonucleoprotein component was measured. The method was very sensitive and reproducible, and did not require preliminary serum fractionation for the identification of antibodies of different immunoglobulin classes. The results showed that the IgA and IgG antibodies against the intact virus persisted in the sera of patients long after the initial infection. In contrast, IgA and IgG antibodies against the ribonucleoprotein component of rubella virus were detected only in sera of patients after recent rubella infection. This observation suggested that a test for antibodies to the ribonucleoprotein component may provide additional evidence in the diagnosis of recent rubella infection. This could be potentially a useful test particularly in the management of pregnant patients. (U.K.)

  2. Adult T-cell leukemia-associated antigen (ATLA): detection of a glycoprotein in cell- and virus-free supernatant.

    Science.gov (United States)

    Yamamoto, N; Schneider, J; Hinuma, Y; Hunsmann, G

    1982-01-01

    A glycoprotein of an apparent molecular mass of 46,000, gp 46, was enriched by affinity chromatography from the virus- and cell-free culture medium of adult T-cell leukemia virus (ATLV) infected cells. gp 46 was specifically precipitated with sera from patients with adult T-cell leukemia associated antigen (ATLA). Thus, gp 46 is a novel component of the ATLA antigen complex.

  3. Neutralizing antibody fails to impact the course of Ebola virus infection in monkeys.

    Directory of Open Access Journals (Sweden)

    Wendelien B Oswald

    2007-01-01

    Full Text Available Prophylaxis with high doses of neutralizing antibody typically offers protection against challenge with viruses producing acute infections. In this study, we have investigated the ability of the neutralizing human monoclonal antibody, KZ52, to protect against Ebola virus in rhesus macaques. This antibody was previously shown to fully protect guinea pigs from infection. Four rhesus macaques were given 50 mg/kg of neutralizing human monoclonal antibody KZ52 intravenously 1 d before challenge with 1,000 plaque-forming units of Ebola virus, followed by a second dose of 50 mg/kg antibody 4 d after challenge. A control animal was exposed to virus in the absence of antibody treatment. Passive transfer of the neutralizing human monoclonal antibody not only failed to protect macaques against challenge with Ebola virus but also had a minimal effect on the explosive viral replication following infection. We show that the inability of antibody to impact infection was not due to neutralization escape. It appears that Ebola virus has a mechanism of infection propagation in vivo in macaques that is uniquely insensitive even to high concentrations of neutralizing antibody.

  4. Radioimmunoassay of Herpes simplex virus antibody: correlation with ganglionic infection

    International Nuclear Information System (INIS)

    Forghani, B.; Klassen, T.; Baringer, J.R.

    1977-01-01

    Results of herpes simplex virus (HSV) isolation from a series of human post-mortem trigeminal thoracic and sacral ganglia were correlated with HSV antibody type(s) detected in the sera by radioimmunoassay (RIA). HSV type I was isolated from trigeminal ganglia of 44 out of 90 individuals, from thoracic ganglia of 1 out of 25, and from sacral ganglia of 1 out of 68 cases. HSV type was recovered from sacral ganglia of 8 out of 68 individuals. In all cases in which an HSV was isolated from ganglia and was available for testing, homologous, type-specific antibody was demonstrable, and in a few instances antibody to the heterologous HSV was also detected. In those individuals in which HSV type I was isolated from trigeminal ganglia and HSV type 2 from sacral ganglia, antibody to both virus types was present in the sera, indicating that simultaneous latent infections with each of the two viruses can occur, and that antibody is produced to each virus independently. Antibody to HSV type 1, 2 or both types was demonstrated in 8 out of 10 cases in which virus isolation attempts were negative, suggesting either a higher sensitivity of RIA for detecting HSV infection, or the presence of latent HSV at some other site in the body which was not sampled. (author)

  5. The use of monoclonal antibodies in competitive ELISA for the detection of antibodies to rinderpest and peste des petits ruminants viruses

    International Nuclear Information System (INIS)

    Anderson, J.; McKay, J.A.; Butcher, R.N.

    1991-01-01

    A monoclonal antibody against the haemagglutinin of rinderpest virus has been used in a competitive ELISA (C-ELISA) for the detection of antibodies to rinderpest virus in cattle, sheep, goat and game sera. Unlike the indirect ELISA and the virus neutralisation test (VNT), the C-ELISA detects only antibodies to rinderpest virus and gives no cross-reactivity with antibodies to peste des petits ruminants (PPR) virus. Antibodies to a wide range of strains of rinderpest virus have been detected using this assay, suggesting its suitability for both sero-monitoring and sero-surveillance. Analysis of C-ELISA results from the examination of field sera shows a much greater separation of negative and positive populations as compared to the indirect ELISA. A further monoclonal antibody against the H protein of PPR has also been found suitable for use in a C-ELISA for the detection of antibodies to PPR virus. The use of these two C-ELISA's has made possible rapid differential sero-diagnosis without recourse to cross-VNT testing. The use of monoclonal antibody-based assays will allow much greater standardisation of rinderpest and PPR diagnosis, and following field-trials the C-ELISA will replace the indirect ELISA for sero-monitoring throughout the Pan African Rinderpest Campaign. (author). 3 refs, 6 figs, 1 tab

  6. Murine leukemia viruses: objects and organisms.

    Science.gov (United States)

    Rein, Alan

    2011-01-01

    Murine leukemia viruses (MLVs) are among the simplest retroviruses. Prototypical gammaretroviruses encode only the three polyproteins that will be used in the assembly of progeny virus particles. These are the Gag polyprotein, which is the structural protein of a retrovirus particle, the Pol protein, comprising the three retroviral enzymes-protease, which catalyzes the maturation of the particle, reverse transcriptase, which copies the viral RNA into DNA upon infection of a new host cell, and integrase, which inserts the DNA into the chromosomal DNA of the host cell, and the Env polyprotein, which induces the fusion of the viral membrane with that of the new host cell, initiating infection. In general, a productive MLV infection has no obvious effect upon host cells. Although gammaretroviral structure and replication follow the same broad outlines as those of other retroviruses, we point out a number of significant differences between different retroviral genera.

  7. JST Thesaurus Headwords and Synonyms: murine leukemia virus [MeCab user dictionary for science technology term[Archive

    Lifescience Database Archive (English)

    Full Text Available MeCab user dictionary for science technology term murine leukemia virus 名詞 一般 * * *... * マウス白血病ウイルス マウスハッケツビョウウイルス マウスハッケツビョーウイルス Thesaurus2015 200906060491156251 C LS07 UNKNOWN_2 murine leukemia virus

  8. Antiphospholipid antibodies in Brazilian hepatitis C virus carriers

    Directory of Open Access Journals (Sweden)

    A.M. Atta

    2008-06-01

    Full Text Available Hepatitis C, a worldwide viral infection, is an important health problem in Brazil. The virus causes chronic infection, provoking B lymphocyte dysfunction, as represented by cryoglobulinemia, non-organ-specific autoantibody production, and non-Hodgkin's lymphoma. The aim of this research was to screen for the presence of antiphospholipid autoantibodies in 109 Brazilian hepatitis C virus carriers without clinical history of antiphospholipid syndrome. Forty healthy individuals were used as the control group. IgA, IgG, and IgM antibodies against cardiolipin and β2-glycoprotein I were measured with an enzyme-linked immunosorbent assay, using a cut-off point of either 20 UPL or 20 SBU. While 24 (22.0% hepatitis C carriers had moderate titers of IgM anticardiolipin antibodies (median, 22.5 MPL; 95%CI: 21.5-25.4 MPL, only three carriers (<3% had IgG anticardiolipin antibodies (median, 23 GPL; 95%CI: 20.5-25.5 GPL. Furthermore, IgA anticardiolipin antibodies were not detected in these individuals. Male gender and IgM anticardiolipin seropositivity were associated in the hepatitis C group (P = 0.0004. IgA anti-β2-glycoprotein-I antibodies were detected in 29 of 109 (27.0% hepatitis C carriers (median, 41 SAU; 95%CI: 52.7-103.9 SAU. Twenty patients (18.0% had IgM anti-β2-glycoprotein I antibodies (median, 27.6 SMU; 95%CI: 23.3-70.3 SMU, while two patients had IgG antibodies against this protein (titers, 33 and 78 SGU. Antiphospholipid antibodies were detected in only one healthy individual, who was seropositive for IgM anticardiolipin. We concluded that Brazilian individuals chronically infected with hepatitis C virus present a significant production of antiphospholipid antibodies, mainly IgA anti-β2-glycoprotein I antibodies, which are not associated with clinical manifestations of antiphospholipid syndrome.

  9. Serological survey of Toxoplasma gondii, Dirofilaria immitis, Feline Immunodeficiency Virus (FIV) and Feline Leukemia Virus (FeLV) infections in pet cats in Bangkok and vicinities, Thailand.

    Science.gov (United States)

    Sukhumavasi, Woraporn; Bellosa, Mary L; Lucio-Forster, Araceli; Liotta, Janice L; Lee, Alice C Y; Pornmingmas, Pitcha; Chungpivat, Sudchit; Mohammed, Hussni O; Lorentzen, Leif; Dubey, J P; Bowman, Dwight D

    2012-08-13

    The seroprevalence of Toxoplasma gondii, Dirofilaria immitis (heartworm), feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) infections was examined using serum or plasma samples from 746 pet cats collected between May and July 2009 from clinics and hospitals located in and around Bangkok, Thailand. The samples were tested for heartworm, FIV, and FeLV using a commercial ELISA. Of the 746 samples, 4.6% (34/746) were positive for heartworm antigen, 24.5% (183/746) had circulating FeLV antigen, and 20.1% (150/746) had antibodies against FIV. In addition, the first 348 submitted samples were tested for T. gondii antibodies using a modified agglutination test (MAT, cut off 1:25); 10.1% (35/348) were seropositive. Of the 348 cats sampled for all four pathogens, 11, 10, and 1 were positive for T. gondii antibodies and FIV antibodies, FeLV antigen, or D. immitis antigen, respectively. Of the 35 T. gondii-seropositive cats, 42.9% (15/35) were co-infected with at least one of the other three pathogens. The presence of antibodies to FIV was significantly associated with both age and gender, while FeLV antigen presence was only associated with age. In the case of FIV, males were twice as likely to be infected as females, and cats over 10 years of age were 13.5 times more likely to be infected than cats less than 1 year of age. FeLV antigen was more common in younger cats, with cats over 10 years of age being 10 times less likely to be FeLV positive than cats under 1 year of age. This is the first survey for these four pathogens affecting feline health in Thailand. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Transgene stability for three replication competent murine leukemia virus vectors

    DEFF Research Database (Denmark)

    Duch, M.; Carrasco, M.L.; Jespersen, T.

    2004-01-01

    cassette consisting of an internal ribosome entry site followed by the enhanced green fluorescent protein coding sequence inserted in different configurations into murine leukemia virus genomes. In two of the constructs, the insert was located in the upstream part of the U3 region while in the third...

  11. Search for infective mammalian type-C virus-related genes in the DNA of human sarcomas and leukemias.

    Science.gov (United States)

    Nicolson, M O; Gilden, R V; Charman, H; Rice, N; Heberling, R; McAllister, R M

    1978-06-15

    DNA was extracted from two human sarcoma cell lines, TE-32 and TE-418, and the leukemic cells from five children with acute myelocytic leukemia, three children with acute lymphocytic leukemia and four adults with acute myelocytic leukemia. The DNAs, assayed for infectivity by transfection techniques, induced no measurable virus by methods which would detect known mammalian C-type antigens or RNA-directed DNA polymerase in TE-32, D-17 dog cells and other indicator cells, nor did they recombine with or rescue endogenous human or exogenous murine or baboon type-C virus. Model systems used as controls were human sarcoma cells, TE-32 and HT-1080, and human lymphoma cells TE-543, experimentally infected with KiMuLV, GaLV or baboon type-C virus, all of which released infectious virus and whose DNAs were infectious for TE-32 and D-17 dog cells. Other model systems included two baboon placentas and one embryonic cell strain spontaneously releasing infectious endogenous baboon virus and yielding DNAs infectious for D-17 dog cells but not for TE-32 cells. Four other baboon embryonic tissues and two embryonic cell strains, releasing either low levels of virus or no virus, did not yield infectious DNA.

  12. Formation of infectious dengue virus-antibody immune complex in vivo in marmosets (Callithrix jacchus) after passive transfer of anti-dengue virus monoclonal antibodies and infection with dengue virus.

    Science.gov (United States)

    Moi, Meng Ling; Ami, Yasushi; Shirai, Kenji; Lim, Chang-Kweng; Suzaki, Yuriko; Saito, Yuka; Kitaura, Kazutaka; Saijo, Masayuki; Suzuki, Ryuji; Kurane, Ichiro; Takasaki, Tomohiko

    2015-02-01

    Infection with a dengue virus (DENV) serotype induces cross-reactive, weakly neutralizing antibodies to different dengue serotypes. It has been postulated that cross-reactive antibodies form a virus-antibody immune complex and enhance DENV infection of Fc gamma receptor (FcγR)-bearing cells. We determined whether infectious DENV-antibody immune complex is formed in vivo in marmosets after passive transfer of DENV-specific monoclonal antibody (mAb) and DENV inoculation and whether infectious DENV-antibody immune complex is detectable using FcγR-expressing cells. Marmosets showed that DENV-antibody immune complex was exclusively infectious to FcγR-expressing cells on days 2, 4, and 7 after passive transfer of each of the mAbs (mAb 4G2 and mAb 6B6C) and DENV inoculation. Although DENV-antibody immune complex was detected, contribution of the passively transferred antibody to overall viremia levels was limited in this study. The results indicate that DENV cross-reactive antibodies form DENV-antibody immune complex in vivo, which is infectious to FcγR-bearing cells but not FcγR-negative cells. © The American Society of Tropical Medicine and Hygiene.

  13. Cellular Promyelocytic Leukemia Protein Is an Important Dengue Virus Restriction Factor

    OpenAIRE

    Giovannoni, Federico; Damonte, Elsa B.; Garc?a, Cybele C.

    2015-01-01

    The intrinsic antiviral defense is based on cellular restriction factors that are constitutively expressed and, thus, active even before a pathogen enters the cell. The promyelocytic leukemia (PML) nuclear bodies (NBs) are discrete nuclear foci that contain several cellular proteins involved in intrinsic antiviral responses against a number of viruses. Accumulating reports have shown the importance of PML as a DNA virus restriction factor and how these pathogens evade this antiviral activity....

  14. In vitro and in vivo antivirus activity of an anti-programmed death-ligand 1 (PD-L1 rat-bovine chimeric antibody against bovine leukemia virus infection.

    Directory of Open Access Journals (Sweden)

    Asami Nishimori

    Full Text Available Programmed death-1 (PD-1, an immunoinhibitory receptor on T cells, is known to be involved in immune evasion through its binding to PD-ligand 1 (PD-L1 in many chronic diseases. We previously found that PD-L1 expression was upregulated in cattle infected with bovine leukemia virus (BLV and that an antibody that blocked the PD-1/PD-L1 interaction reactivated T-cell function in vitro. Therefore, this study assessed its antivirus activities in vivo. First, we inoculated the anti-bovine PD-L1 rat monoclonal antibody 4G12 into a BLV-infected cow. However, this did not induce T-cell proliferation or reduction of BLV provirus loads during the test period, and only bound to circulating IgM+ B cells until one week post-inoculation. We hypothesized that this lack of in vivo effects was due to its lower stability in cattle and so established an anti-PD-L1 rat-bovine chimeric antibody (Boch4G12. Boch4G12 was able to bind specifically with bovine PD-L1, interrupt the PD-1/PD-L1 interaction, and activate the immune response in both healthy and BLV-infected cattle in vitro. Therefore, we experimentally infected a healthy calf with BLV and inoculated it intravenously with 1 mg/kg of Boch4G12 once it reached the aleukemic (AL stage. Cultivation of peripheral blood mononuclear cells (PBMCs isolated from the tested calf indicated that the proliferation of CD4+ T cells was increased by Boch4G12 inoculation, while BLV provirus loads were significantly reduced, clearly demonstrating that this treatment induced antivirus activities. Therefore, further studies using a large number of animals are required to support its efficacy for clinical application.

  15. Identification and typing of herpes simplex viruses with monoclonal antibodies.

    OpenAIRE

    Balachandran, N; Frame, B; Chernesky, M; Kraiselburd, E; Kouri, Y; Garcia, D; Lavery, C; Rawls, W E

    1982-01-01

    Monoclonal antibodies which reacted with type-specific antigens of herpes simplex virus type 2 or with antigens shared by herpes simplex virus types 1 and 2 were used in an indirect immunofluorescence assay to type virus isolates and to detect viral antigens in cells obtained from herpetic lesions. Complete concordance was obtained for 42 isolates typed by endonuclease restriction analysis of viral DNA and by indirect immunofluorescence with monoclonal antibodies. Examination of a limited num...

  16. Inability of Kaplan radiation leukemia virus to replicate on mouse fibroblasts is conferred by its long terminal repeat

    International Nuclear Information System (INIS)

    Rassart, E.; Paquette, Y.; Jolicoeur, P.

    1988-01-01

    The molecularly cloned infectious Kaplan radiation leukemia virus has previously been shown to be unable to replicate on mouse fibroblasts. To map the viral sequences responsible for this, we constructed chimeric viral DNA genomes in vitro with parental cloned infectious viral DNAs from the nonfibrotropic (F-) BL/VL3 V-13 radiation leukemia virus and the fibrotropic (F+) endogenous BALB/c or Moloney murine leukemia viruses (MuLV). Infectious chimeric MuLVs, recovered after transfection of Ti-6 lymphocytes with these recombinant DNAs, were tested for capacity to replicate on mouse fibroblasts in vitro. We found that chimeric MuLVs harboring the long terminal repeat (LTR) of a fibrotropic MuLV replicated well on mouse fibroblasts. Conversely, chimeric MuLVs harboring the LTR of a nonfibrotropic MuLV were restricted on mouse fibroblasts. These results indicate that the LTR of BL/VL3 radiation leukemia virus harbors the primary determinant responsible for its inability to replicate on mouse fibroblasts in vitro. Our results also show that the primary determinant allowing F+ MuLVs (endogenous BALB/c and Moloney MuLVs) to replicate on mouse fibroblasts in vitro resides within the LTR

  17. Evaluation of a new in-clinic test system to detect feline immunodeficiency virus and feline leukemia virus infection.

    Science.gov (United States)

    Sand, Christina; Englert, Theresa; Egberink, Herman; Lutz, Hans; Hartmann, Katrin

    2010-06-01

    Many in-house tests for the diagnosis of feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) infection are licensed for use in veterinary practice. A new test with unknown performance has recently appeared on the market. The aims of this study were to define the efficacy of a new in-clinic test system, the Anigen Rapid FIV Ab/FeLV Ag Test, and to compare it with the current leading in-clinic test, the SNAP Kombi Plus FeLV Antigen/FIB Antibody Test. Three-hundred serum samples from randomly selected healthy and diseased cats presented to the Clinic of Small Animal Medicine at Ludwig Maximilian University were tested using both the Anigen Rapid Test and the SNAP Kombi Plus Test. Diagnostic sensitivity, specificity, and positive and negative predictive values were calculated for both tests using Western blot as the gold standard for verification of FIV infection and PCR as the gold standard for FeLV infection. The presence of antibodies against FIV was confirmed by Western blot in 9/300 samples (prevalence 3%). FeLV DNA was detected by PCR in 15/300 samples (prevalence 5%). For FIV infection the Anigen Rapid Test had a sensitivity of 88.9%, specificity of 99.7%, positive predictive value of 88.9%, and negative predictive value of 99.7%. For FeLV infection, the Anigen Rapid Test had a sensitivity of 40.0%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 96.9%. Diagnostic accuracy was similar to that of the SNAP Kombi Plus Test. The new Anigen Rapid FIV Ab/FeLV Ag Test performed very well and can be recommended for use in veterinary practice.

  18. Subtype-Specific Influenza A Virus Antibodies in Canada Geese (Branta canadensis)

    Science.gov (United States)

    Kistler, Whitney M.; Stallknecht, David E.; DeLiberto, Thomas J.; Van Why, Kyle; Yabsley, Michael J.

    2015-01-01

    Historically, surveillance for influenza A viruses (IAVs) in wild birds has relied on viral detection assays. This was largely due to poor performance of serological assays in wild birds; however, recently developed commercial serological assays have improved the ability to detect IAV antibodies in wild birds. Serological surveillance for IAV antibodies in Canada geese (Branta canadensis) has shown that, despite a low prevalence of virus isolations, Canada geese are frequently exposed to IAVs and that exposure increases with latitude, which follows virus isolation prevalence patterns observed in dabbling ducks. The objectives of this study were to further evaluate IAV antibodies in Canada geese using a subtype-specific serological assay to determine if Canada geese are exposed to subtypes that commonly circulate in dabbling ducks. We collected serum samples from Canada geese in Minnesota, New Jersey, Pennsylvania, and Wisconsin and tested for antibodies to IAVs using a blocking ELISA. Positive samples were further tested by hemagglutination inhibition for 10 hemagglutinin IAV subtypes (H1–H10). Overall, we detected antibodies to NP in 24% (714/2,919) of geese. Antibodies to H3, H4, H5, and H6 subtypes predominated, with H5 being detected most frequently. A decrease in H5 HI antibody prevalence and titers was observed from 2009 to 2012. We also detected similar exposure pattern in Canada geese from New Jersey, Minnesota, Washington and Wisconsin. Based on the published literature, H3, H4, and H6 viruses are the most commonly reported IAVs from dabbling ducks. These results indicate that Canada geese also are frequently exposed to viruses of the same HA subtypes; however, the high prevalence of antibodies to H5 viruses was not expected as H5 IAVs are generally not well represented in reported isolates from ducks. PMID:25845755

  19. Neonatal respiratory syncytial virus infection: role of transplacentally and breast milk-acquired antibodies.

    OpenAIRE

    Wong, D T; Ogra, P L

    1986-01-01

    The effect of transplacentally and breast milk-acquired antibodies on respiratory syncytial virus infection was studied in neonatal and 2-month-old cotton rats. Adult female rats infected intranasally with live virus regularly produced virus-specific antibodies in the serum, colostrum, and breast milk. By using foster feeding techniques, we showed that both transplacentally and breast milk-acquired antibodies were effective in reducing the replication of respiratory syncytial virus in the lun...

  20. Monoclonal antibodies directed to E1 glycoprotein of rubella virus

    International Nuclear Information System (INIS)

    Umino, Y.; Sato, A.; Katow, S.; Matsuno, T.; Sugiura, A.

    1985-01-01

    We have prepared four monoclonal antibodies to rubella virus E1 glycoprotein. Three nonoverlapping antigenic sites were delineated on E1 protein by competitive binding assays. Antibodies binding to one site were characterized by high hemagglutination inhibition (HI) titer but poor neutralizing activity. The addition of antiglobulin conferred neutralizing activity. Antibodies directed to two other antigenic sites had modest hemolysis inhibition but little or no HI and neutralizing activities. The addition of antiglobulin markedly augmented HI activity but had little effect on neutralizing activity. Epitopes defined by three antibodies were conserved among four rubella virus strains examined. (Author)

  1. Immune response to inactivated influenza virus vaccine: antibody reactivity with epidemic influenza B viruses of two highly distinct evolutionary lineages.

    Science.gov (United States)

    Pyhälä, R; Kleemola, M; Kumpulainen, V; Vartiainen, E; Lappi, S; Pönkä, A; Cantell, K

    1992-01-01

    Vaccination of adults (healthy female employees potentially capable of transmitting influenza to high-risk persons; n = 104) in autumn 1990 with a trivalent influenza virus vaccine containing B/Yamagata/16/88 induced a low antibody response to B/Finland/150/90, a recent variant of B/Victoria/2/87-like viruses, as compared with the antibody response to B/Finland/172/91, a current variant in the lineage of B/Yamagata/16/88-like viruses. Up to the end of the epidemic season, the antibody status declined but was still significantly better than before the vaccination. The results suggest that the vaccine strain was appropriate for the outbreak of 1990 to 1991 in Finland, but may provide unsatisfactory protection against B/Victoria/2/87-like viruses. Evidence is given that use of Madin-Darby canine kidney (MDCK)-grown virus as an antigen in the haemagglutination inhibition test (HI) may provide more reliable information about the protective antibodies than use of untreated or ether-treated egg-grown viruses. Significantly higher postvaccination and postepidemic antibody titres were recorded among subjects who exhibited the antibody before vaccination than among seronegative subjects. A significantly higher response rate among initially seronegative people than among seropositive people was recorded for antibody to B/Finland/150/90, but no clear evidence was obtained that the pre-existing antibody could have had a negative effect on the antibody production.

  2. Seroprevalence of feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) in shelter cats on the island of Newfoundland, Canada.

    Science.gov (United States)

    Munro, Hannah J; Berghuis, Lesley; Lang, Andrew S; Rogers, Laura; Whitney, Hugh

    2014-04-01

    Feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) are retroviruses found within domestic and wild cat populations. These viruses cause severe illnesses that eventually lead to death. Housing cats communally for long periods of time makes shelters at high risk for virus transmission among cats. We tested 548 cats from 5 different sites across the island of Newfoundland for FIV and FeLV. The overall seroprevalence was 2.2% and 6.2% for FIV and FeLV, respectively. Two sites had significantly higher seroprevalence of FeLV infection than the other 3 sites. Analysis of sequences from the FeLV env gene (envelope gene) from 6 positive cats showed that 4 fell within the FeLV subtype-A, while 2 sequences were most closely related to FeLV subtype-B and endogenous feline leukemia virus (en FeLV). Varying seroprevalence and the variation in sequences at different sites demonstrate that some shelters are at greater risk of FeLV infections and recombination can occur at sites of high seroprevalence.

  3. Comparisons of Venezuelan encephalitis virus strains by hemagglutination-inhibition tests with chicken antibodies.

    Science.gov (United States)

    Scherer, W F; Pancake, B A

    1977-01-01

    Twenty strains of Venezuelan encephalitis (VE) virus inoculated intravenously in large doses into roosters produced hemagglutination-inhibition (HI) antibodies detectable in plasmas within 7 to 10 days. No signs of illness occurred, and there was no evidence of viral growth in tissues since blood concentrations of infectious virus steadily decreased after inoculation. HI antibodies in early plasmas were specific for VE virus and did not cross-react significantly with two other North American alphaviruses, eastern and western encephalitis viruses. VE virus strains could be distinquished by virus-dilution, short-incubation HI, but not by plasma-dilution neutralization tests, by using early rooster antibodies. The distinctions by HI test were similar with some strains to, but different with other strains from, those described by Young and Johnson with the spiny rat antisera used to establish their subtype classifications of VE virus (14, 28). Nevertheless, results of HI tests with rooster antibodies correlated with equine virulence, as did results with spiny rat antibodies, and distinguished the new strains of virus that appeared in Middle America during the VE outbreak of 1969 from preexisting strains. PMID:591629

  4. Genotyping of feline leukemia virus in Mexican housecats.

    Science.gov (United States)

    Ramírez, Hugo; Autran, Marcela; García, M Martha; Carmona, M Ángel; Rodríguez, Cecilia; Martínez, H Alejandro

    2016-04-01

    Feline leukemia virus (FeLV) is a retrovirus with variable rates of infection globally. DNA was obtained from cats' peripheral blood mononuclear cells, and proviral DNA of pol and env genes was detected using PCR. Seventy-six percent of cats scored positive for FeLV using env-PCR; and 54 %, by pol-PCR. Phylogenetic analysis of both regions identified sequences that correspond to a group that includes endogenous retroviruses. They form an independent branch and, therefore, a new group of endogenous viruses. Cat gender, age, outdoor access, and cohabitation with other cats were found to be significant risk factors associated with the disease. This strongly suggests that these FeLV genotypes are widely distributed in the studied feline population in Mexico.

  5. Impaired antibody response causes persistence of prototypic T cell-contained virus.

    Directory of Open Access Journals (Sweden)

    Andreas Bergthaler

    2009-04-01

    Full Text Available CD8 T cells are recognized key players in control of persistent virus infections, but increasing evidence suggests that assistance from other immune mediators is also needed. Here, we investigated whether specific antibody responses contribute to control of lymphocytic choriomeningitis virus (LCMV, a prototypic mouse model of systemic persistent infection. Mice expressing transgenic B cell receptors of LCMV-unrelated specificity, and mice unable to produce soluble immunoglobulin M (IgM exhibited protracted viremia or failed to resolve LCMV. Virus control depended on immunoglobulin class switch, but neither on complement cascades nor on Fc receptor gamma chain or Fc gamma receptor IIB. Cessation of viremia concurred with the emergence of viral envelope-specific antibodies, rather than with neutralizing serum activity, and even early nonneutralizing IgM impeded viral persistence. This important role for virus-specific antibodies may be similarly underappreciated in other primarily T cell-controlled infections such as HIV and hepatitis C virus, and we suggest this contribution of antibodies be given consideration in future strategies for vaccination and immunotherapy.

  6. Duration of Maternal Antibodies against Canine Distemper Virus and Hendra Virus in Pteropid Bats

    Science.gov (United States)

    Zambrana-Torrelio, Carlos; Middleton, Deborah; Barr, Jennifer A.; DuBovi, Edward; Boyd, Victoria; Pope, Brian; Todd, Shawn; Crameri, Gary; Walsh, Allyson; Pelican, Katey; Fielder, Mark D.; Davies, Angela J.; Wang, Lin-Fa; Daszak, Peter

    2013-01-01

    Old World frugivorous bats have been identified as natural hosts for emerging zoonotic viruses of significant public health concern, including henipaviruses (Nipah and Hendra virus), Ebola virus, and Marburg virus. Epidemiological studies of these viruses in bats often utilize serology to describe viral dynamics, with particular attention paid to juveniles, whose birth increases the overall susceptibility of the population to a viral outbreak once maternal immunity wanes. However, little is understood about bat immunology, including the duration of maternal antibodies in neonates. Understanding duration of maternally derived immunity is critical for characterizing viral dynamics in bat populations, which may help assess the risk of spillover to humans. We conducted two separate studies of pregnant Pteropus bat species and their offspring to measure the half-life and duration of antibodies to 1) canine distemper virus antigen in vaccinated captive Pteropus hypomelanus; and 2) Hendra virus in wild-caught, naturally infected Pteropus alecto. Both of these pteropid bat species are known reservoirs for henipaviruses. We found that in both species, antibodies were transferred from dam to pup. In P. hypomelanus pups, titers against CDV waned over a mean period of 228.6 days (95% CI: 185.4–271.8) and had a mean terminal phase half-life of 96.0 days (CI 95%: 30.7–299.7). In P. alecto pups, antibodies waned over 255.13 days (95% CI: 221.0–289.3) and had a mean terminal phase half-life of 52.24 days (CI 95%: 33.76–80.83). Each species showed a duration of transferred maternal immunity of between 7.5 and 8.5 months, which was longer than has been previously estimated. These data will allow for more accurate interpretation of age-related Henipavirus serological data collected from wild pteropid bats. PMID:23826322

  7. Development and clinical evaluation of a rapid diagnostic kit for feline leukemia virus infection.

    Science.gov (United States)

    Kim, Won-Shik; Chong, Chom-Kyu; Kim, Hak-Yong; Lee, Gyu-Cheol; Jeong, Wooseog; An, Dong-Jun; Jeoung, Hye-Young; Lee, Jae-In; Lee, Young-Ki

    2014-01-01

    Feline leukemia virus (FeLV) causes a range of neoplastic and degenerative diseases in cats. To obtain a more sensitive and convenient diagnosis of the disease, we prepared monoclonal antibodies specific for the FeLV p27 to develop a rapid diagnostic test with enhanced sensitivity and specificity. Among these antibodies, we identified two clones (hybridomas 8F8B5 and 8G7D1) that specifically bound to FeLV and were very suitable for a diagnostic kit. The affinity constants for 8F8B5 and 8G7D1 were 0.35 × 10⁸ and 0.86 × 10⁸, respectively. To investigate the diagnostic abilities of the rapid kit using these antibodies, we performed several clinical studies. Assessment of analytical sensitivity revealed that the detection threshold of the rapid diagnostic test was 2 ng/mL for recombinant p27 and 12.5 × 10⁴ IU/mL for FeLV. When evaluating 252 cat sera samples, the kit was found to have a kappa value of 0.88 compared to polymerase chain reaction (PCR), indicating a significant correlation between data from the rapid diagnostic test and PCR. Sensitivity and specificity of the kit were 95.2% (20/21) and 98.5% (257/261), respectively. Our results demonstrated that the rapid diagnostic test would be a suitable diagnostic tool for the rapid detection of FeLV infection in cats.

  8. Neutralizing Antibodies and Pathogenesis of Hepatitis C Virus Infection

    Directory of Open Access Journals (Sweden)

    Françoise Stoll-Keller

    2012-10-01

    Full Text Available Hepatitis C virus (HCV infection is a major cause of chronic liver disease worldwide. The interplay between the virus and host innate and adaptive immune responses determines the outcome of infection. There is increasing evidence that host neutralizing responses play a relevant role in the resulting pathogenesis. Furthermore, viral evasion from host neutralizing antibodies has been revealed to be an important contributor in leading both to viral persistence in acute liver graft infection following liver transplantation, and to chronic viral infection. The development of novel model systems to study HCV entry and neutralization has allowed a detailed understanding of the molecular mechanisms of virus-host interactions during antibody-mediated neutralization. The understanding of these mechanisms will ultimately contribute to the development of novel antiviral preventive strategies for liver graft infection and an urgently needed vaccine. This review summarizes recent concepts of the role of neutralizing antibodies in viral clearance and protection, and highlights consequences of viral escape from neutralizing antibodies in the pathogenesis of HCV infection.

  9. Anti-JC virus antibody prevalence in a multinational multiple sclerosis cohort

    DEFF Research Database (Denmark)

    Olsson, Tomas; Achiron, Anat; Alfredsson, Lars

    2013-01-01

    JC virus (JCV) is an opportunistic virus known to cause progressive multifocal leukoencephalopathy. Anti-JC virus (Anti-JCV) antibody prevalence in a large, geographically diverse, multi-national multiple sclerosis (MS) cohort was compared in a cross-sectional study. Overall, anti-JCV antibody...... prevalence was 57.6%. Anti-JCV antibody prevalence in MS patients ranged from approximately 47% to 68% across these countries: Norway, 47.4%; Denmark, 52.6%; Israel, 56.6%; France, 57.6%; Italy, 58.3%; Sweden, 59.0%; Germany, 59.1%; Austria, 66.7% and Turkey, 67.7%. Prevalence increased with age (from 49...

  10. Sensitive radioimmunoassay for the determination of antibodies to mouse hepatitis virus

    Energy Technology Data Exchange (ETDEWEB)

    Leibowitz, J L [California Univ., San Diego, La Jolla (USA); Fung, L S; Levy, G A [Toronto Univ., Ontario (Canada)

    1983-05-01

    A solid-phase radioimmunoassay is described for the detection of antibodies to mouse hepatitis virus. Viruses were purified by velocity and isopycnic gradient centrifugation and 96-well plastic plates were coated with viral antigens. To allow the detection of most serotypes of low titered antisera, a pool of antigens from several viral serotypes were employed. The second antibody, an affinity-purified goat antimouse immunoglobulin, detects IgG, IgM and IgA antibodies. This assay is more sensitive than either the plaque reduction assay or the commercially available enzyme-linked immunosorbant assay and proved to be useful for screening mouse colonies for the presence of mouse hepatitis virus, following seroconversion in experimental animals and in the production of monoclonal antibodies to both structural and nonstructural proteins.

  11. Androgen-independent proliferation of LNCaP prostate cancer cells infected by xenotropic murine leukemia virus-related virus

    International Nuclear Information System (INIS)

    Kakoki, Katsura; Kamiyama, Haruka; Izumida, Mai; Yashima, Yuka; Hayashi, Hideki; Yamamoto, Naoki; Matsuyama, Toshifumi; Igawa, Tsukasa; Sakai, Hideki; Kubo, Yoshinao

    2014-01-01

    Highlights: • XMRV infection induces androgen-independent growth in LNCaP cells. • XMRV infection reduces expression of androgen receptor. • XMRV promotes appearance of androgen blocker-resistant prostate cancer cells. - Abstract: Xenotropic murine leukemia virus-related virus (XMRV) is a novel gammaretrovirus that was originally isolated from human prostate cancer. It is now believed that XMRV is not the etiologic agent of prostate cancer. An analysis of murine leukemia virus (MLV) infection in various human cell lines revealed that prostate cancer cell lines are preferentially infected by XMRV, and this suggested that XMRV infection may confer some sort of growth advantage to prostate cancer cell lines. To examine this hypothesis, androgen-dependent LNCaP cells were infected with XMRV and tested for changes in certain cell growth properties. We found that XMRV-infected LNCaP cells can proliferate in the absence of the androgen dihydrotestosterone. Moreover, androgen receptor expression is significantly reduced in XMRV-infected LNCaP cells. Such alterations were not observed in uninfected and amphotropic MLV-infected LNCaP cells. This finding explains why prostate cancer cell lines are preferentially infected with XMRV

  12. Targeting Human C-Type Lectin-Like Molecule-1 (CLL1) with a Bispecific Antibody for Acute Myeloid Leukemia Immunotherapy**

    OpenAIRE

    Lu, Hua; Zhou, Quan; Deshmukh, Vishal; Phull, Hardeep; Ma, Jennifer; Tardif, Virginie; Naik, Rahul R.; Bouvard, Claire; Zhang, Yong; Choi, Seihyun; Lawson, Brian R.; Zhu, Shoutian; Kim, Chan Hyuk; Schultz, Peter G.

    2014-01-01

    Acute myeloid leukemia (AML), the most common acute adult leukemia and the second most common pediatric leukemia, still has a poor prognosis. Human C-type lectin-like molecule-1 (CLL1) is a recently identified myeloid lineage restricted cell surface marker, which is overexpressed in over 90% of AML patient myeloid blasts and in leukemic stem cells. Here, we describe the synthesis of a novel bispecific antibody, αCLL1-αCD3, using the genetically encoded unnatural amino acid, p-acetylphenylalan...

  13. Antibody responses to Hepatitis B and measles-mumps-rubella vaccines in children who received chemotherapy for acute lymphoblastic leukemia

    Directory of Open Access Journals (Sweden)

    Simone Santana Viana

    2012-01-01

    Full Text Available OBJECTIVE: To evaluate viral vaccine antibody levels in children with acute lymphoblastic leukemia after chemotherapy and after vaccine booster doses. METHODS: Antibody levels against hepatitis B, rubella, measles and mumps vaccine antigens were evaluated in 33 children after completing chemotherapy (before and after vaccine booster doses and the results were compared to the data of 33 healthy children matched for gender, age and social class. RESULTS: After chemotherapy, 75.9%, 67.9%, 59.3% and 51.7% of the patients showed low antibody titers that would be unlikely to protect against exposure to measles, rubella, hepatitis B and mumps, respectively. After receiving a vaccine booster dose for these antigens the patients had high antibody levels consistent with potential protection against measles, mumps and hepatitis B, but not against rubella. CONCLUSION: Extra doses of measles-mumps-rubella plus hepatitis B vaccines are recommended in acute lymphoblastic leukemia patients submitted to treatment after hematologic recovery. After this, viral vaccine antibody levels should be verified to define the individual's protective status.

  14. EPSTEIN-BARR VIRUS INFECTIONS – AVIDITY TEST FOR IgG ANTIBODIES

    Directory of Open Access Journals (Sweden)

    Katja Strašek

    2001-06-01

    Full Text Available Background. We wish to introduce specific IgG avidity test as a supplementary assay in serological screening for Epstein-Barr virus infection if the status of patient cannot be resolved from a single serum sample with routine testing.Methods. Avidity of IgG antibodies was determined in sera of 57 patients with different stage of Epstein-Barr virus infection. Enzyme-immuno assay was used with a short incubation of 6-molar urea included in the procedure. Urea should remove low avidity antibodies. Avidity was expressed as the avidity index. Avidity testing with commercial kit was done as well.Results. Low avidity index was found for IgG antibodies of acute phase sera and high for those of past infection, recent infection and reactivation of endogenic virus.Conclusions. Avidity test for IgG antibodies might be supplementary assay to prove acute infection but also to resolve some other clinical states related to Epstein-Barr virus.

  15. Discordance between bovine leukemia virus tax immortalization in vitro and oncogenicity in vivo.

    Science.gov (United States)

    Twizere, J C; Kerkhofs, P; Burny, A; Portetelle, D; Kettmann, R; Willems, L

    2000-11-01

    Bovine leukemia virus (BLV) Tax protein, a transcriptional activator of viral expression, is essential for viral replication in vivo. Tax is believed to be involved in leukemogenesis because of its second function, immortalization of primary cells in vitro. These activities of Tax can be dissociated on the basis of point mutations within specific regions of the protein. For example, mutation of the phosphorylation sites at serines 106 and 293 abrogates immortalization potential in vitro but maintains transcriptional activity. This type of mutant is thus particularly useful for unraveling the role of Tax immortalization activity during leukemogenesis independently of viral replication. In this report, we describe the biological properties of BLV recombinant proviruses mutated in the Tax phosphorylation sites (BLVTax106+293). Titration of the proviral loads by semiquantitative PCR revealed that the BLV mutants propagated at wild-type levels in vivo. Furthermore, two animals (sheep 480 and 296) infected with BLVTax106+293 developed leukemia or lymphosarcoma after 16 and 36 months, respectively. These periods of time are within the normal range of latencies preceding the onset of pathogenesis induced by wild-type viruses. The phenotype of the mutant-infected cells was characteristic of a B lymphocyte (immunoglobulin M positive) expressing CD11b and CD5 (except at the final stage for the latter marker), a pattern that is typical of wild-type virus-infected target cells. Interestingly, the transformed B lymphocytes from sheep 480 also coexpressed the CD8 marker, a phenotype rarely observed in tumor biopsies from chronic lymphocytic leukemia patients. Finally, direct sequencing of the tax gene demonstrated that the leukemic cells did not harbor revertant proviruses. We conclude that viruses expressing a Tax mutant unable to transform primary cells in culture are still pathogenic in the sheep animal model. Our data thus provide a clear example of the discordant conclusions

  16. Post-infection immunodeficiency virus control by neutralizing antibodies.

    Directory of Open Access Journals (Sweden)

    Hiroyuki Yamamoto

    Full Text Available BACKGROUND: Unlike most acute viral infections controlled with the appearance of virus-specific neutralizing antibodies (NAbs, primary HIV infections are not met with such potent and early antibody responses. This brings into question if or how the presence of potent antibodies can contribute to primary HIV control, but protective efficacies of antiviral antibodies in primary HIV infections have remained elusive; and, it has been speculated that even NAb induction could have only a limited suppressive effect on primary HIV replication once infection is established. Here, in an attempt to answer this question, we examined the effect of passive NAb immunization post-infection on primary viral replication in a macaque AIDS model. METHODS AND FINDINGS: The inoculums for passive immunization with simian immunodeficiency virus mac239 (SIVmac239-specific neutralizing activity were prepared by purifying polyclonal immunoglobulin G from pooled plasma of six SIVmac239-infected rhesus macaques with NAb induction in the chronic phase. Passive immunization of rhesus macaques with the NAbs at day 7 after SIVmac239 challenge resulted in significant reduction of set-point plasma viral loads and preservation of central memory CD4 T lymphocyte counts, despite the limited detection period of the administered NAb responses. Peripheral lymph node dendritic cell (DC-associated viral RNA loads showed a remarkable peak with the NAb administration, and DCs stimulated in vitro with NAb-preincubated SIV activated virus-specific CD4 T lymphocytes in an Fc-dependent manner, implying antibody-mediated virion uptake by DCs and enhanced T cell priming. CONCLUSIONS: Our results present evidence indicating that potent antibody induction post-infection can result in primary immunodeficiency virus control and suggest direct and indirect contribution of its absence to initial control failure in HIV infections. Although difficulty in achieving requisite neutralizing titers for

  17. Monoclonal antibodies against plant viruses

    International Nuclear Information System (INIS)

    Sandler, E.; Dietzgen, R.G.

    1984-01-01

    Ever since antigenic properties of plant viruses were discovered antisera have been raised and used for plant virus diagnosis and for the analysis of virus structure as well. From the early qualitative diagnosis method of precipitating the virus in clarified sap of an infected plant and the first quantitative application of the precipitin test vast progress has been made with regard to the development of highly sensitive and highly quantitative methods for virus detection. Of equal importance was the improvement of methods for separating virus from host cell components since the specificity of antisera raised against a virus could be increased by using an antigen for immunization highly concentrated and largely freed from contaminating host substances. The introduction of the enzyme-linked immunosorbent assay (ELISA) into plant virology allows detection of virus in nanogram quantities. Still, the conventionally raised antisera, no matter how pure an antigen was used for immunization, are polyclonal. They contain products of thousands of different antibody-secreting plasma cell clones which can be directed against all antigenic determinants (epitopes) of the virus, but also against antigens of the host plant that may not have been entirely separated from the immunizing virus during the purification procedure. Even after cross adsorption of polyclonal antisera some residual heterogeneity can be expected to remain. Within these boundaries the information gained with polyclonal antisera on virus structure and on virus diagnosis has to be interpreted

  18. Radioimmunoassay of bovine leukosis virus antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Franz, J; Hampl, J; Svoboda, I; Granatova, M; Hofirek, B; Skrobak, F

    1986-08-01

    A RIA method was developed for identifying the presence of serum antibodies to the bovine leukosis virus. The chosen procedure uses the ability of the virus antigen to bind to the solid phase of a polystyrene carrier. The method was compared with the ELISA method and with the pseudoneutralization and immunodiffusion tests. A high level of agreement was achieved between the RIA and the ELISA methods (95%). By its accuracy the RIA method proves superior to the immunodiffusion test.

  19. Neutralisation and binding of VHS virus by monovalent antibody fragments

    DEFF Research Database (Denmark)

    Cupit, P.M.; Lorenzen, Niels; Strachan, G.

    2001-01-01

    We have previously reported the cloning and characterisation of the heavy and light chain variable domain genes encoding three monoclonal antibodies (Mabs) that bind viral haemorrhagic septicaemia virus (VHSV). Two of these antibodies, 3F1H10 and 3F1A2 both neutralised the virus though 3F1A2...... appeared to recognise a broader range of virus isolates. The variable domains of these two antibodies differ by only four residues (Lorenzen et al., 2000a. Fish Shellfish Immunol. 10, 129-142). To further study the mechanism of neutralisation, Fab fragments as well as a series of recombinant bacterial...... single chain antibody (scAb) fragments were generated from the three anti-VHSV Mabs and their variable domain genes, respectively. Fabs and scAbs derived from the neutralising Mabs were both able to neutralise the VHSV type 1 isolate DK-F1. In addition, a series of scAb fragments were produced using...

  20. An influenza A virus agglutination test using antibody-like polymers.

    Science.gov (United States)

    Sukjee, Wannisa; Thitithanyanont, Arunee; Wiboon-Ut, Suwimon; Lieberzeit, Peter A; Paul Gleeson, M; Navakul, Krongkaew; Sangma, Chak

    2017-10-01

    Antibodies are commonly used in diagnostic routines to identify pathogens. The testing protocols are relatively simple, requiring a certain amount of a specific antibody to detect its corresponding pathogen. Antibody functionality can be mimicked by synthesizing molecularly imprinted polymers (MIPs), i.e. polymers that can selectively recognize a given template structure. Thus, MIPs are sometimes termed 'plastic antibody (PA)'. In this study, we have synthesized new granular MIPs using influenza A virus templates by precipitation polymerization. The selective binding of influenza A to the MIP particles was assessed and subsequently contrasted with other viruses. The affinities of influenza A virus towards the MIP was estimated based on an agglutination test by measuring the amount of influenza subtypes absorbed onto the MIPs. The MIPs produced using the H1N1 template showed specific reactivity to H1N1 while those produced using H5N1 and H3N2 templates showed cross-reactivity.

  1. AKT capture by feline leukemia virus.

    Science.gov (United States)

    Kawamura, Maki; Umehara, Daigo; Odahara, Yuka; Miyake, Ariko; Ngo, Minh Ha; Ohsato, Yoshiharu; Hisasue, Masaharu; Nakaya, Masa-Aki; Watanabe, Shinya; Nishigaki, Kazuo

    2017-04-01

    Oncogene-containing retroviruses are generated by recombination events between viral and cellular sequences, a phenomenon called "oncogene capture". The captured cellular genes, referred to as "v-onc" genes, then acquire new oncogenic properties. We report a novel feline leukemia virus (FeLV), designated "FeLV-AKT", that has captured feline c-AKT1 in feline lymphoma. FeLV-AKT contains a gag-AKT fusion gene that encodes the myristoylated Gag matrix protein and the kinase domain of feline c-AKT1, but not its pleckstrin homology domain. Therefore, it differs structurally from the v-Akt gene of murine retrovirus AKT8. AKT may be involved in the mechanisms underlying malignant diseases in cats.

  2. Pan-ebolavirus and Pan-filovirus Mouse Monoclonal Antibodies: Protection against Ebola and Sudan Viruses.

    Science.gov (United States)

    Holtsberg, Frederick W; Shulenin, Sergey; Vu, Hong; Howell, Katie A; Patel, Sonal J; Gunn, Bronwyn; Karim, Marcus; Lai, Jonathan R; Frei, Julia C; Nyakatura, Elisabeth K; Zeitlin, Larry; Douglas, Robin; Fusco, Marnie L; Froude, Jeffrey W; Saphire, Erica Ollmann; Herbert, Andrew S; Wirchnianski, Ariel S; Lear-Rooney, Calli M; Alter, Galit; Dye, John M; Glass, Pamela J; Warfield, Kelly L; Aman, M Javad

    2016-01-01

    The unprecedented 2014-2015 Ebola virus disease (EVD) outbreak in West Africa has highlighted the need for effective therapeutics against filoviruses. Monoclonal antibody (MAb) cocktails have shown great potential as EVD therapeutics; however, the existing protective MAbs are virus species specific. Here we report the development of pan-ebolavirus and pan-filovirus antibodies generated by repeated immunization of mice with filovirus glycoproteins engineered to drive the B cell responses toward conserved epitopes. Multiple pan-ebolavirus antibodies were identified that react to the Ebola, Sudan, Bundibugyo, and Reston viruses. A pan-filovirus antibody that was reactive to the receptor binding regions of all filovirus glycoproteins was also identified. Significant postexposure efficacy of several MAbs, including a novel antibody cocktail, was demonstrated. For the first time, we report cross-neutralization and in vivo protection against two highly divergent filovirus species, i.e., Ebola virus and Sudan virus, with a single antibody. Competition studies indicate that this antibody targets a previously unrecognized conserved neutralizing epitope that involves the glycan cap. Mechanistic studies indicated that, besides neutralization, innate immune cell effector functions may play a role in the antiviral activity of the antibodies. Our findings further suggest critical novel epitopes that can be utilized to design effective cocktails for broad protection against multiple filovirus species. Filoviruses represent a major public health threat in Africa and an emerging global concern. Largely driven by the U.S. biodefense funding programs and reinforced by the 2014 outbreaks, current immunotherapeutics are primarily focused on a single filovirus species called Ebola virus (EBOV) (formerly Zaire Ebola virus). However, other filoviruses including Sudan, Bundibugyo, and Marburg viruses have caused human outbreaks with mortality rates as high as 90%. Thus, cross

  3. Characterization of Ebola virus entry by using pseudotyped viruses: identification of receptor-deficient cell lines.

    Science.gov (United States)

    Wool-Lewis, R J; Bates, P

    1998-04-01

    Studies analyzing Ebola virus replication have been severely hampered by the extreme pathogenicity of this virus. To permit analysis of the host range and function of the Ebola virus glycoprotein (Ebo-GP), we have developed a system for pseudotyping these glycoproteins into murine leukemia virus (MLV). This pseudotyped virus, MLV(Ebola), can be readily concentrated to titers which exceed 5 x 10(6) infectious units/ml and is effectively neutralized by antibodies specific for Ebo-GP. Analysis of MLV(Ebola) infection revealed that the host range conferred by Ebo-GP is very broad, extending to cells of a variety of species. Notably, all lymphoid cell lines tested were completely resistant to infection; we speculate that this is due to the absence of a cellular receptor for Ebo-GP on B and T cells. The generation of high-titer MLV(Ebola) pseudotypes will be useful for the analysis of immune responses to Ebola virus infection, development of neutralizing antibodies, analysis of glycoprotein function, and isolation of the cellular receptor(s) for the Ebola virus.

  4. Feline leukemia virus and feline immunodeficiency virus in Canada: recommendations for testing and management.

    Science.gov (United States)

    Little, Susan; Bienzle, Dorothee; Carioto, Lisa; Chisholm, Hugh; O'Brien, Elizabeth; Scherk, Margie

    2011-08-01

    Feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) are common and important infectious disease agents of cats in Canada. Seroprevalence data for FeLV and FIV in various populations of Canadian cats are reviewed and recommendations for testing and management of infections by these viruses in cats in Canada are presented. Retrovirus testing in Canada is infrequent in comparison with the United States, and efforts should be focused on reducing physical and other barriers to testing, and on education of veterinarians, veterinary team members, and cat owners regarding the importance of testing. New test methodologies for FeLV and FIV are emerging, and should be independently evaluated in order to provide practitioners with information on test reliability. Finally, more information is needed on FIV subtypes in Canada to improve diagnostics and vaccines, and to provide information on disease outcomes.

  5. Prevalence and titers of yellow fever virus neutralizing antibodies in previously vaccinated adults.

    Science.gov (United States)

    Miyaji, Karina Takesaki; Avelino-Silva, Vivian Iida; Simões, Marisol; Freire, Marcos da Silva; Medeiros, Carlos Roberto de; Braga, Patrícia Emilia; Neves, Maria Angélica Acalá; Lopes, Marta Heloisa; Kallas, Esper Georges; Sartori, Ana Marli Christovam

    2017-04-03

    The World Health Organization (WHO) recommends one single dose of the Yellow Fever (YF) vaccine based on studies of antibody persistency in healthy adults. We assessed the prevalence and titers of YF virus neutralizing antibodies in previously vaccinated persons aged  60 years, in comparison to younger adults. We also evaluated the correlation between antibody titers and the time since vaccination among participants who received one vaccine dose, and the seropositivity among participants vaccinated prior to or within the past 10 years. previously vaccinated healthy persons aged  18 years were included. YF virus neutralizing antibody titers were determined by means of the 50% Plaque Reduction Neutralization Test. 46 persons aged  60 years and 48 persons aged 18 to 59 years were enrolled. There was no significant difference in the prevalence of YF virus neutralizing antibodies between the two groups (p = 0.263). However, titers were significantly lower in the elderly (p = 0.022). There was no correlation between YF virus neutralizing antibody titers and the time since vaccination. There was no significant difference in seropositivity among participants vaccinated prior to or within the past 10 years. the clinical relevance of the observed difference in YF virus neutralizing antibody titers between the two groups is not clear.

  6. Development of human antibody fragments using antibody phage display for the detection and diagnosis of Venezuelan equine encephalitis virus (VEEV

    Directory of Open Access Journals (Sweden)

    Hust Michael

    2008-09-01

    Full Text Available Abstract Background Venezuelan equine encephalitis virus (VEEV belongs to the Alphavirus group. Several species of this family are also pathogenic to humans and are recognized as potential agents of biological warfare and terrorism. The objective of this work was the generation of recombinant antibodies for the detection of VEEV after a potential bioterrorism assault or an natural outbreak of VEEV. Results In this work, human anti-VEEV single chain Fragments variable (scFv were isolated for the first time from a human naïve antibody gene library using optimized selection processes. In total eleven different scFvs were identified and their immunological specificity was assessed. The specific detection of the VEEV strains TC83, H12/93 and 230 by the selected antibody fragments was proved. Active as well as formalin inactivated virus particles were recognized by the selected antibody fragments which could be also used for Western blot analysis of VEEV proteins and immunohistochemistry of VEEV infected cells. The anti-VEEV scFv phage clones did not show any cross-reactivity with Alphavirus species of the Western equine encephalitis virus (WEEV and Eastern equine encephalitis virus (EEEV antigenic complex, nor did they react with Chikungunya virus (CHIKV, if they were used as detection reagent. Conclusion For the first time, this study describes the selection of antibodies against a human pathogenic virus from a human naïve scFv antibody gene library using complete, active virus particles as antigen. The broad and sensitive applicability of scFv-presenting phage for the immunological detection and diagnosis of Alphavirus species was demonstrated. The selected antibody fragments will improve the fast identification of VEEV in case of a biological warfare or terroristic attack or a natural outbreak.

  7. Vaccine-induced anti-HA2 antibodies promote virus fusion and enhance influenza virus respiratory disease.

    Science.gov (United States)

    Khurana, Surender; Loving, Crystal L; Manischewitz, Jody; King, Lisa R; Gauger, Phillip C; Henningson, Jamie; Vincent, Amy L; Golding, Hana

    2013-08-28

    Vaccine-induced disease enhancement has been described in connection with several viral vaccines in animal models and in humans. We investigated a swine model to evaluate mismatched influenza vaccine-associated enhanced respiratory disease (VAERD) after pH1N1 infection. Vaccinating pigs with whole inactivated H1N2 (human-like) virus vaccine (WIV-H1N2) resulted in enhanced pneumonia and disease after pH1N1 infection. WIV-H1N2 immune sera contained high titers of cross-reactive anti-pH1N1 hemagglutinin (HA) antibodies that bound exclusively to the HA2 domain but not to the HA1 globular head. No hemagglutination inhibition titers against pH1N1 (challenge virus) were measured. Epitope mapping using phage display library identified the immunodominant epitope recognized by WIV-H1N2 immune sera as amino acids 32 to 77 of pH1N1-HA2 domain, close to the fusion peptide. These cross-reactive anti-HA2 antibodies enhanced pH1N1 infection of Madin-Darby canine kidney cells by promoting virus membrane fusion activity. The enhanced fusion activity correlated with lung pathology in pigs. This study suggests a role for fusion-enhancing anti-HA2 antibodies in VAERD, in the absence of receptor-blocking virus-neutralizing antibodies. These findings should be considered during the evaluation of universal influenza vaccines designed to elicit HA2 stem-targeting antibodies.

  8. Lichen planus, liver kidney microsomal (LKM1) antibodies and hepatitis C virus antibodies.

    Science.gov (United States)

    Divano, M C; Parodi, A; Rebora, A

    1992-01-01

    No anti-liver kidney microsomal (LKM1) antibodies were detected in 46 patients with LP, 16 of whom had also a chronic liver disease (CLD). In contrast, anti-hepatitis C virus (HCV) antibodies were found in 10% of patients with LP and in 50% of those with LP and CLD. Anti-HCV antibodies may be considered as a false-positive reaction in 56% of cases, especially when anti-LKM1 antibodies are present. Our findings do not support such a hypothesis, but suggest that CLD in LP patients is, at least in Italy, mostly a postviral chronic active hepatitis.

  9. Radioimmunoassay of bovine leukosis virus antibodies

    International Nuclear Information System (INIS)

    Franz, J.; Hampl, J.; Svoboda, I.; Granatova, M.; Hofirek, B.; Skrobak, F.

    1986-01-01

    A RIA method was developed for identifying the presence of serum antibodies to the bovine leukosis virus. The chosen procedure uses the ability of the virus antigen to bind to the solid phase of a polystyrene carrier. The method was compared with the ELISA method and with the pseudoneutralization and immunodiffusion tests. A high level of agreement was achieved between the RIA and the ELISA methods (95%). By its accuracy the RIA method proves superior to the immunodiffusion test. (author)

  10. Human antibodies to the dengue virus E-dimer epitope have therapeutic activity against Zika virus infection.

    Science.gov (United States)

    Fernandez, Estefania; Dejnirattisai, Wanwisa; Cao, Bin; Scheaffer, Suzanne M; Supasa, Piyada; Wongwiwat, Wiyada; Esakky, Prabagaran; Drury, Andrea; Mongkolsapaya, Juthathip; Moley, Kelle H; Mysorekar, Indira U; Screaton, Gavin R; Diamond, Michael S

    2017-11-01

    The Zika virus (ZIKV) epidemic has resulted in congenital abnormalities in fetuses and neonates. Although some cross-reactive dengue virus (DENV)-specific antibodies can enhance ZIKV infection in mice, those recognizing the DENV E-dimer epitope (EDE) can neutralize ZIKV infection in cell culture. We evaluated the therapeutic activity of human monoclonal antibodies to DENV EDE for their ability to control ZIKV infection in the brains, testes, placentas, and fetuses of mice. A single dose of the EDE1-B10 antibody given 3 d after ZIKV infection protected against lethality, reduced ZIKV levels in brains and testes, and preserved sperm counts. In pregnant mice, wild-type or engineered LALA variants of EDE1-B10, which cannot engage Fcg receptors, diminished ZIKV burden in maternal and fetal tissues, and protected against fetal demise. Because neutralizing antibodies to EDE have therapeutic potential against ZIKV, in addition to their established inhibitory effects against DENV, it may be possible to develop therapies that control disease caused by both viruses.

  11. Monoclonal antibodies to Herpes Simplex Virus Type 2

    International Nuclear Information System (INIS)

    McLean-Pieper, C.S.

    1982-01-01

    In this thesis the production and characterisation of monoclonal antibodies to Herpes Simplex Virus Type 2 is described. The development of a suitable radioimmunoassay for the detection of anti-HSV-2 antibodies, and the selection of an optimal immunisation schedule, is given. Three assay systems are described and their reliability and sensitivity compared. (Auth.)

  12. Antibody-mediated immunotherapy against chronic hepatitis B virus infection.

    Science.gov (United States)

    Gao, Ying; Zhang, Tian-Ying; Yuan, Quan; Xia, Ning-Shao

    2017-08-03

    The currently available drugs to treat hepatitis B virus (HBV) infection include interferons and nucleos(t)ide analogs, which can only induce disease remission and are inefficient for the functional cure of patients with chronic HBV infection (CHB). Since high titers of circulating hepatitis B surface antigen (HBsAg) may be essential to exhaust the host anti-HBV immune response and they cannot be significantly reduced by current drugs, new antiviral strategies aiming to suppress serum hepatitis B surface antigen (HBsAg) could help restore virus-specific immune responses and promote the eradication of the virus. As an alternative strategy, immunotherapy with HBsAg-specific antibodies has shown some direct HBsAg suppression effects in several preclinical and clinical trial studies. However, most described previously HBsAg-specific antibodies only had very short-term HBsAg suppression effects in CHB patients and animal models mimicking persistent HBV infection. More-potent antibodies with long-lasting HBsAg clearance effects are required for the development of the clinical application of antibody-mediated immunotherapy for CHB treatment. Our recent study described a novel mAb E6F6 that targets a unique epitope on HBsAg. It could durably suppress the levels of HBsAg and HBV DNA via Fcγ receptor-dependent phagocytosis in vivo. In this commentary, we summarize the current research progress, including the therapeutic roles and mechanisms of antibody-mediated HBV clearance as well as the epitope-determined therapeutic potency of the antibody. These insights may provide some clues and guidance to facilitate the development of therapeutic antibodies against persistent viral infection.

  13. A sensitive radioimmunoassay for the determination of antibodies to mouse hepatitis virus

    International Nuclear Information System (INIS)

    Leibowitz, J.L.; Fung, L.S.; Levy, G.A.

    1983-01-01

    A solid-phase radioimmunoassay is described for the detection of antibodies to mouse hepatitis virus. Viruses were purified by velocity and isopycnic gradient centrifugation and 96-well plastic plates were coated with viral antigens. To allow the detection of most serotypes of low titered antisera, a pool of antigens from several viral serotypes were employed. The second antibody, an affinity-purified goat antimouse immunoglobulin, detects IgG, IgM and IgA antibodies. This assay is more sensitive than either the plaque reduction assay or the commercially available enzyme-linked immunosorbant assay and proved to be useful for screening mouse colonies for the presence of mouse hepatitis virus, following seroconversion in experimental animals and in the production of monoclonal antibodies to both structural and nonstructural proteins. (Auth.)

  14. Measles and canine distemper virus antibodies in patients with multiple sclerosis determined by radioimmunoassay

    International Nuclear Information System (INIS)

    Arnadottir, T.

    1980-01-01

    Antibodies against measles virus (MV) and canine distemper virus (CDV) were measured by solid-phase radioimmunoassay (RIA) of sera and cerebrospinal fluid (CSF) from 28 patients with multiple sclerosis (MS) and matched neurological controls. When the groups were compared for MV antibody titers and CDV antibody titers of sera and MV/CDV serum antibody titer ratios, no significant difference was found. The CDV antibody titers and the MV antibody titers were in good correlation. CDV antibodies showed RIA titration curves typical of low avidity antibodies. In tests for MV antibodies in CSF, 82% of the MS patients and 19% of the controls were positive, whereas 36% of the MS patients and 4% of the controls were positive in CDV RIA. The correlation between MV and CDV antibody levels, the low avidity of CDV antibodies and the fact that absorption of the specimens with MV antigen abolished all CDV antibody activity suggest that the CDV antibodies are MV antibodies cross-reacting with CDV. It is concluded that canine distemper virus is unlikely to be involved in the etiology of multiple sclerosis. (author)

  15. Detection of antibodies to transmissible gastroenteritis virus of swine by modified autoradiographic test

    Energy Technology Data Exchange (ETDEWEB)

    Stepanek, J; Hampl, J; Franz, J; Mensik, P; Skrobak, F [Vyzkumny Ustav Veterinarniho Lekarstvi, Brno-Medlanky (Czechoslovakia)

    1982-08-01

    A modified method of autoradiographic determination of virus antibodies of gastroenteritis of swine was developed. It is based on the actual reaction between antigen bound in cells of the infected cell cultures and antibodies in tested sera, which is visualized by rabbit antibodies labelled with /sup 125/I (/sup 125/I RaSw IgG antibody) to porcine IgG, on a sensitive radiograph and evaluated by darkening at the point of positive immunological reaction. Specificity of the test and mutual comparability and reproducibility of the results were confirmed by examining the known positive and negative sera and by a comparison with the results of the virus-neutralization test. Of the 36 examined porcine blood sera, antibodies were only proved autoradiographically in the samples positive also by virus-neutralization. In experimentally infected pigs, the same dynamics of antibody production was recorded by the two tests. They were, however, demonstrated autoradiographically the eighth day after infection, while by virus neutralization test as late as 14th day. Their level increased gradually till 35th day after infection.

  16. Detection systems for antibody responses against herpes B virus

    OpenAIRE

    Pöhlmann, Stefan; Krüger, Astrid; Hafezi, Wali; Schneider, Stefan; Gruber, Jens; Winkler, Michael; Kaul, Artur

    2017-01-01

    Herpes B virus (BV) infection is highly prevalent among adult Asian macaques and rarely causes severe disease in infected animals. In contrast, BV infection of humans can induce fatal encephalitis in the absence of treatment. Therefore, the development of diagnostic tests for specific and sensitive detection of antibodies against BV is an important task. The cross-reactivity of antibodies against BV with related simplex viruses of other primates may afford an opportunity to ...

  17. Quantitation, in vitro propagation, and characterization of preleukemic cells induced by radiation leukemia virus

    International Nuclear Information System (INIS)

    Yefenof, E.; Epszteyn, S.; Kotler, M.

    1991-01-01

    Intrathymic (i.t.) inoculation of radiation leukemia virus into C57BL/6 mice induces a population of preleukemic (PL) cells that can progress into mature thymic lymphomas upon transfer into syngeneic recipients. A minimum of 10(3) PL thymic cells are required to induce lymphomas in the recipient. Most of the individual lymphomas developed in mice which were inoculated with cells of a single PL thymus, derived from different T-cell precursors. PL thymic cells could be grown in vitro on a feeder layer consisting of splenic stromal cells. Growth medium was supplemented with supernatant harvested from an established radiation leukemia virus-induced lymphoma cell line (SR4). The in vitro-grown PL cells were characterized as Thy-1+, CD4+, CD8- T-cells, most of which expressed radiation leukemia virus antigens. Cultured PL cells were found to be nontumorigenic, based on their inability to form s.c. tumors. However, these cells could develop into thymic lymphomas if inoculated i.t. into syngeneic recipients. A culture of PL cells, maintained for 2 mo, showed clonal T-cell receptor arrangement. Lymphomas which developed in several recipient mice upon injection with these PL cells were found to possess the same T-cell receptor arrangement. These results indicate that PL cells can be adapted for in vitro growth while maintaining their preleukemic character

  18. Antibody-Induced Internalization of the Human Respiratory Syncytial Virus Fusion Protein.

    Science.gov (United States)

    Leemans, A; De Schryver, M; Van der Gucht, W; Heykers, A; Pintelon, I; Hotard, A L; Moore, M L; Melero, J A; McLellan, J S; Graham, B S; Broadbent, L; Power, U F; Caljon, G; Cos, P; Maes, L; Delputte, P

    2017-07-15

    Respiratory syncytial virus (RSV) infections remain a major cause of respiratory disease and hospitalizations among infants. Infection recurs frequently and establishes a weak and short-lived immunity. To date, RSV immunoprophylaxis and vaccine research is mainly focused on the RSV fusion (F) protein, but a vaccine remains elusive. The RSV F protein is a highly conserved surface glycoprotein and is the main target of neutralizing antibodies induced by natural infection. Here, we analyzed an internalization process of antigen-antibody complexes after binding of RSV-specific antibodies to RSV antigens expressed on the surface of infected cells. The RSV F protein and attachment (G) protein were found to be internalized in both infected and transfected cells after the addition of either RSV-specific polyclonal antibodies (PAbs) or RSV glycoprotein-specific monoclonal antibodies (MAbs), as determined by indirect immunofluorescence staining and flow-cytometric analysis. Internalization experiments with different cell lines, well-differentiated primary bronchial epithelial cells (WD-PBECs), and RSV isolates suggest that antibody internalization can be considered a general feature of RSV. More specifically for RSV F, the mechanism of internalization was shown to be clathrin dependent. All RSV F-targeted MAbs tested, regardless of their epitopes, induced internalization of RSV F. No differences could be observed between the different MAbs, indicating that RSV F internalization was epitope independent. Since this process can be either antiviral, by affecting virus assembly and production, or beneficial for the virus, by limiting the efficacy of antibodies and effector mechanism, further research is required to determine the extent to which this occurs in vivo and how this might impact RSV replication. IMPORTANCE Current research into the development of new immunoprophylaxis and vaccines is mainly focused on the RSV F protein since, among others, RSV F-specific antibodies are

  19. Clinical aspects of feline immunodeficiency and feline leukemia virus infection.

    Science.gov (United States)

    Hartmann, Katrin

    2011-10-15

    Feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) are retroviruses with a global impact on the health of domestic cats. The two viruses differ in their potential to cause disease. FIV can cause an acquired immunodeficiency syndrome that increases the risk of developing opportunistic infections, neurological diseases, and tumors. In most naturally infected cats, however, FIV itself does not cause severe clinical signs, and FIV-infected cats may live many years without any health problems. FeLV is more pathogenic, and was long considered to be responsible for more clinical syndromes than any other agent in cats. FeLV can cause tumors (mainly lymphoma), bone marrow suppression syndromes (mainly anemia) and lead to secondary infectious diseases caused by suppressive effects of the virus on bone marrow and the immune system. Today, FeLV is less important as a deadly infectious agent as in the last 20 years prevalence has been decreasing in most countries. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Genetic characterization of feline leukemia virus from Florida panthers.

    Science.gov (United States)

    Brown, Meredith A; Cunningham, Mark W; Roca, Alfred L; Troyer, Jennifer L; Johnson, Warren E; O'Brien, Stephen J

    2008-02-01

    From 2002 through 2005, an outbreak of feline leukemia virus (FeLV) occurred in Florida panthers (Puma concolor coryi). Clinical signs included lymphadenopathy, anemia, septicemia, and weight loss; 5 panthers died. Not associated with FeLV outcome were the genetic heritage of the panthers (pure Florida vs. Texas/Florida crosses) and co-infection with feline immunodeficiency virus. Genetic analysis of panther FeLV, designated FeLV-Pco, determined that the outbreak likely came from 1 cross-species transmission from a domestic cat. The FeLV-Pco virus was closely related to the domestic cat exogenous FeLV-A subgroup in lacking recombinant segments derived from endogenous FeLV. FeLV-Pco sequences were most similar to the well-characterized FeLV-945 strain, which is highly virulent and strongly pathogenic in domestic cats because of unique long terminal repeat and envelope sequences. These unique features may also account for the severity of the outbreak after cross-species transmission to the panther.

  1. A novel reporter system for neutralizing and enhancing antibody assay against dengue virus.

    Science.gov (United States)

    Song, Ke-Yu; Zhao, Hui; Jiang, Zhen-You; Li, Xiao-Feng; Deng, Yong-Qiang; Jiang, Tao; Zhu, Shun-Ya; Shi, Pei-Yong; Zhang, Bo; Zhang, Fu-Chun; Qin, E-De; Qin, Cheng-Feng

    2014-02-18

    Dengue virus (DENV) still poses a global public health threat, and no vaccine or antiviral therapy is currently available. Antibody plays distinct roles in controlling DENV infections. Neutralizing antibody is protective against DENV infection, whereas sub-neutralizing concentration of antibody can increase DENV infection, termed antibody-dependent enhancement (ADE). Plaque-based assay represents the most widely accepted method measuring neutralizing or enhancing antibodies. In this study, a novel reporter virus-based system was developed for measuring neutralization and ADE activity. A stable Renilla luciferase reporter DENV (Luc-DENV) that can produce robust luciferase signals in BHK-21 and K562 cells were used to establish the assay and validated against traditional plaque-based assay. Luciferase value analysis using various known DENV-specific monoclonal antibodies showed good repeatability and a well linear correlation with conventional plaque-based assays. The newly developed assay was finally validated with clinical samples from infected animals and individuals. This reporter virus-based assay for neutralizing and enhancing antibody evaluation is rapid, lower cost, and high throughput, and will be helpful for laboratory detection and epidemiological investigation for DENV antibodies.

  2. Novel Feline Leukemia Virus Interference Group Based on the env Gene.

    Science.gov (United States)

    Miyake, Ariko; Watanabe, Shinya; Hiratsuka, Takahiro; Ito, Jumpei; Ngo, Minh Ha; Makundi, Isaac; Kawasaki, Junna; Endo, Yasuyuki; Tsujimoto, Hajime; Nishigaki, Kazuo

    2016-05-01

    Feline leukemia virus (FeLV) subgroups have emerged in infected cats via the mutation or recombination of the env gene of subgroup A FeLV (FeLV-A), the primary virus. We report the isolation and characterization of a novel env gene, TG35-2, and report that the TG35-2 pseudotype can be categorized as a novel FeLV subgroup. The TG35-2 envelope protein displays strong sequence identity to FeLV-A Env, suggesting that selection pressure in cats causes novel FeLV subgroups to emerge. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  3. Are endogenous feline leukemia viruses really endogenous?

    Science.gov (United States)

    Stewart, H; Jarrett, O; Hosie, M J; Willett, B J

    2011-10-15

    Full length endogenous feline leukemia virus (FeLV) proviruses exist within the genomes of many breeds of domestic cat raising the possibility that they may also exist in a transmissible exogenous form. Such viruses would share receptor usage with the recombinant FeLV-B subgroup, a viral subgroup that arises in vivo by recombination between exogenous subgroup A virus (FeLV-A) and endogenous FeLV. Accordingly, all isolates of FeLV-B made to date have contained a "helper" FeLV-A, consistent with their recombinatorial origin. In order to assess whether endogenous viruses are transmitted between cats, we examined primary isolates of FeLV for which the viral subgroup had been determined for the presence of a subgroup B virus that lacked an FeLV-A. Here we describe the identification of two primary field isolates of FeLV (2518 and 4314) that appeared to contain subgroup B virus only by classical interference assays, raising the possibility of between-host transmission of endogenous FeLV. Sequencing of the env gene and U3 region of the 3' long terminal repeat (LTR) confirmed that both viral genomes contained endogenous viral env genes. However the viral 3' LTRs appeared exogenous in origin with a putative 3' recombination breakpoint residing at the 3' end of the env gene. Further, the FeLV-2518 virions also co-packaged a truncated FeLV-A genome containing a defective env gene, termed FeLV-2518(A) whilst no helper subgroup A viral genome was detected in virions of FeLV-4314. The acquisition of an exogenous LTR by the endogenous FeLV in 4314 may have allowed a recombinant FeLV variant to outgrow an exogenous FeLV-A virus that was presumably present during first infection. Given time, a similar evolution may also occur within the 2518 isolate. The data suggest that endogenous FeLVs may be mobilised by acquisition of exogenous LTRs yielding novel viruses that type biologically as FeLV-B. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Experimental studies of leukemia

    International Nuclear Information System (INIS)

    Yokoro, Kenjiro

    1977-01-01

    Mouse leukemia, especially the relationship between that and endogenous type-C RNA virus (murine leukemia virus, MLV), was generally discussed centering around the recent findings and reports. Correlation of carcinogenesis due to x-rays and carcinogens with the occurrence of MLV, the relationship of total body fractionated x-ray irradiation and successive acellular transmission by the neonatal inoculation with MLV, and the relationship between N-nitrosobutylurea or N-nitrosoethylurea and MLV were discussed. The relationship between the occurrence of MLV and thymus or spleen was also discussed. Biotic differences in mice and rats, the relationship between MLV the organotropism of MLV and provocation of leukemia, the directivity of MLV to thymus and the etiologic correlation of rat leukemia or mouse leukemia with MLV were mentioned. (Ichikawa, K.)

  5. Production of yam mosaic virus monoclonal antibodies in mice ...

    African Journals Online (AJOL)

    Administrator

    2011-09-19

    Sep 19, 2011 ... 4AVRDC-The World Vegetable Center, Shanhua, Taiwan. Accepted 11 August, 2011. Yam mosaic virus (YMV) ... leaves and non-infected tissue culture yam leaves. The antibody produced had a titre of ... systems for in-vitro production of monoclonal antibodies, such as standard tissue culture techniques,.

  6. Seroprevalence and correlates of human T-cell lymphoma/leukemia virus type 1 antibodies among pregnant women at the University of Nigeria Teaching Hospital, Enugu, Nigeria.

    Science.gov (United States)

    Okoye, Augustine Ejike; Ibegbulam, Obike Godswill; Onoh, Robinson Chukwudi; Ezeonu, Paul Olisaemeka; Ugwu, Ngozi I; Lawani, Lucky Osaheni; Anigbo, Chukwudi Simon; Nonyelu, Charles E

    2014-01-01

    Human T-cell lymphoma/leukemia virus (HTLV)-1 is a retrovirus transmitted vertically from mother to child parenterally and sexually by infected lymphocytes. The objective of this study was to determine the seroprevalence of HTLV-1 antibodies and associated risk factors for HTLV-1 infection among pregnant women in University of Nigeria Teaching Hospital, Enugu, southeast Nigeria. A cross-sectional study was carried out from July to October 2010. Two hundred pregnant women were recruited consecutively from the antenatal clinic. Five milliliters of blood was collected from each of the participants into a plain sterile bottle and allowed to clot. The serum obtained was stored at -20°C until required for analysis. The serum samples were then analyzed for antibodies to HTLV-1 using a one-step incubation double-antigen sandwich enzyme-linked immunosorbent assay kit. Participants' demographic characteristics and degree of exposure to the risk factors associated with HTLV-1 infection were captured using a questionnaire. Statistical analysis of results was done using SPSS version 17. The average age of the pregnant women was 28.94 years (standard deviation 4.17). The age-group with the highest representation was those between the ages of 26 and 30 years. Thirty-six percent of the population was above 30 years old. The result of the tests showed that only one respondent, a 31-year-old pregnant woman tested positive for HTLV-1 antibodies. Therefore, the seroprevalence of HTLV-1 antibodies among pregnant women attending the antenatal clinic at University of Nigeria Teaching Hospital was 0.5%, with a 95% confidence interval of 0%-2.8%. Some of the sociodemographic risk factors of HTLV-1 infection found to be applicable to the 31-year-old woman who tested positive included positive history of previous sexually transmitted diseases, high parity, low socioeconomic status, female sex, and age above 30 years. The pregnant women that participated in this study were exposed to risk

  7. A review of feline leukemia virus and feline immunodeficiency virus seroprevalence in cats in Canada.

    Science.gov (United States)

    Little, Susan

    2011-10-15

    Feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) are common and important infectious diseases of cats in Canada. Prevalence data are necessary to define prophylactic, management, and therapeutic measures for stray, feral and owned cats. Recently, comprehensive data on the seroprevalence of retrovirus infections of cats in Canada have become available and are reviewed. Further investigation into geographic variations in retrovirus seroprevalence within Canada is warranted, and may provide information to improve recommendations for testing and prevention. As well, more information is needed on FIV subtypes in Canada to improve diagnostics and vaccines, as well as to provide information on disease outcomes. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. The enhancing effect of fractionated whole-body x-irradiation on replication of endogenous leukemia viruses in BALB/c mice

    International Nuclear Information System (INIS)

    Takamori, Yasuhiko; Okumoto, Masaaki; Iwai, Mineko; Iwai, Yoshiaki

    1976-01-01

    The incidence of leukemia, changes in the tissue weight of spleen and thymus, and the expression of endogenous viruses were examined with BALB/c mice following 4 weekly fractionated whole-body x-irradiation of 170 R each, starting at 4 weeks of age. The leukemia incidence was quite low for the unirradiated controls, while 60% of the irradiated male mice developed thymic lymphoma. The virus-positive cells appeared earlier in the spleen than in the thymus and bone marrow, and increased with aging. The time of appearance of virus-positive cells in these tissues was remarkably promoted by the fractionated x-irradiation, and its frequency was also enhanced. (auth.)

  9. Anti-Erwinia asparaginase antibodies during treatment of childhood acute lymphoblastic leukemia and their relationship to outcome

    DEFF Research Database (Denmark)

    Albertsen, BK; Schmiegelow, Kjeld; Schrøder, Henrik

    2002-01-01

    PURPOSE: A case-control study was performed to determine whether patients who had been treated with Erwinia asparaginase as part of their treatment for childhood acute lymphoblastic leukemia (ALL) and who showed relapsed of their disease more often developed anti-asparaginase antibodies than...... (median follow-up 70 months). Anti- Erwinia asparaginase antibodies were measured (ELISA method) during maintenance therapy after asparaginase treatment (30,000 IU/m(2) daily for 10 days in all patients plus twice weekly for 2 weeks in intermediate-risk and high-risk ALL patients). RESULTS: The overall...... incidence of anti- Erwinia asparaginase antibodies was 8% (3 of 39 patients). There was no statistically significant difference in the incidence of antibody formation between patients who had suffered relapse (1 of 13) and those who had not (2 of 26). In two of the three patients who developed antibodies...

  10. Cis-drivers and trans-drivers of bovine leukemia virus oncogenesis.

    Science.gov (United States)

    Safari, Roghaiyeh; Hamaidia, Malik; de Brogniez, Alix; Gillet, Nicolas; Willems, Luc

    2017-10-01

    The bovine leukemia virus (BLV) is a retrovirus inducing an asymptomatic and persistent infection in ruminants and leading in a minority of cases to the accumulation of B-lymphocytes (lymphocytosis, leukemia or lymphoma). Although the mechanisms of oncogenesis are still largely unknown, there is clear experimental evidence showing that BLV infection drastically modifies the pattern of gene expression of the host cell. This alteration of the transcriptome in infected B-lymphocytes results first, from a direct activity of viral proteins (i.e. transactivation of gene promoters, protein-protein interactions), second, from insertional mutagenesis by proviral integration (cis-activation) and third, from gene silencing by microRNAs. Expression of viral proteins stimulates a vigorous immune response that indirectly modifies gene transcription in other cell types (e.g. cytotoxic T-cells, auxiliary T-cells, macrophages). In principle, insertional mutagenesis and microRNA-associated RNA interference can modify the cell fate without inducing an antiviral immunity. Despite a tight control by the immune response, the permanent attempts of the virus to replicate ultimately induce mutations in the infected cell. Accumulation of these genomic lesions and Darwinian selection of tumor clones are predicted to lead to cancer. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Detection of Xenotropic Murine Leukemia Virus-Related Virus in Prostate Biopsy Samples

    International Nuclear Information System (INIS)

    Baig, F. A.; Mirza, T.; Khanani, R.; Khan, S.

    2014-01-01

    Objective: To determine the association of Xenotropic murine leukemia virus related virus (XMRV) infection with prostate cancer and compare it with benign prostate hyperplasia. Study Design: Case control study. Place and Duration of Study: Department of Histopathology and Molecular Pathology, Dow University of Health Sciences, Karachi, from January 2009 to December 2012. Methodology: XMRV was screened in 50 prostate cancer and 50 benign prostatic hyperplasia biopsies using conventional end-point PCR. Other studied variables were family history of prostate cancer, patients age and Gleason score. Results: XMRV was detected in 4 (8%) of the 50 prostate cancer biopsy specimens compared to none in biopsies with benign prostatic hyperplasia. However, there was no significant statistical association of XMRV infection with the other variables. Conclusion: A low frequency of XMRV infection was found in this case-control study. Men, who harbor XMRV infection, may be at increased risk of prostate cancer but this needs to be investigated further at a larger scale. (author)

  12. Hepatitis B and A virus antibodies in alcoholic steatosis and cirrhosis

    DEFF Research Database (Denmark)

    Gluud, C; Aldershvile, J; Henriksen, J

    1982-01-01

    Sera from 74 alcoholics with cirrhosis and 63 alcoholics with steatosis were tested for antibody to hepatitis B surface antigen, to hepatitis B core antigen, and to hepatitis A virus by radioimmunoassay or enzyme-linked immunosorbent assay. No significant difference between the two groups...... of alcoholics could be found concerning the prevalence of these antibodies. The total group of patients had antibody to hepatitis B surface antigen or hepatitis B core antigen, or both, significantly (p less than 0.001) more often (26%) than sex- and age-matched controls (4%). No significant difference...... was found between patients and controls concerning the prevalence of antibody to hepatitis A virus (46% v 40%). In patients with cirrhosis, no correlation between wedged hepatic vein pressure or wedged-to-free hepatic vein pressure and any of the viral antibodies could be established. The present results...

  13. A radioimmunoassay for anti-virus antibodies in farm animals

    International Nuclear Information System (INIS)

    Rodak, L.; Smid, B.; Sedlacek, M.

    1978-01-01

    A radioimmunoassay for determination of antibodies to Aujeszky's disease virus in piq serum is described. The results show a number of advantaqes of this method over the routinely employed virus-neutralization test. The possibility of using the RIA method in diagnosing other viral diseases of farm animals is suggested. (authors)

  14. Bovine leukemia virus seroprevalence among cattle presented for slaughter in the United States

    Science.gov (United States)

    Infection with bovine leukemia virus (BLV) results in economic loss due reduced productivity, especially the reduction of milk production and early culling. In the USA.,USA, previous studies in 1996, 1999 and 2007 showed BLV infections widespread, especially in the dairy herds. The goal of this stud...

  15. Prevalence of Hepatitis A Virus Antibody in Portuguese Travelers: A New Paradigm.

    Science.gov (United States)

    Rocha, Sónia; Tejo, Sandra; Ferreira, Eugénia; Trindade, Luís; Rabadão, Eduardo; Marques, Nuno; Saraiva da Cunha, José

    2017-08-31

    In Portugal, the prevalence of hepatitis A virus infection has decreased in the past decades, especially in young adults. The aim of this study was to detect the prevalence of antibody to hepatitis A virus in a population observed in our Travel Clinic. Antibodies against hepatitis A, hepatitis B, hepatitis C and human immunodeficiency virus were tested using standard enzyme immunoassay in patients older than 18. The exclusion criteria were: prior vaccination for hepatitis A virus, previous diagnosis of infection with hepatitis B virus, hepatitis C virus and/or human immunodeficiency virus, foreign travelers and long-term expatriates. We applied an epidemiological survey and data was statistically analyzed with SPSS® 18.0. In the 665 travelers studied, natural immunity to hepatitis A virus was present in 57.6% (n = 383). They were stratified into 8 age groups and for each one hepatitis A immunity was clarified: 5.0% (n = 1) in 18 - 25 years, 32.3% (n = 21) in 26 - 30 years, 40.9% (n = 47) in 31 - 35 years, 45.8% (n = 54) in 36 - 40 years, 68.7% (n = 79) in 41 - 45 years, 70.1% (n = 68) in 46 - 50 years, 80.8% (n = 63) in 51 - 55 years and 87.7% (n = 50) over 56 years old. In those who accepted further screening, positivity for hepatitis B core antibody was found in 0.6% (n = 3) travelers, hepatitis C virus infection in 1.1% (n = 6) and human immunodeficiency virus infection in 0.5% (n = 3) whose previous status was unknown. The most frequent travel destination was sub-Saharan Africa (72.6%; n = 483). We found 49.1% (n = 260) travelers under 50 years old susceptible to hepatitis A virus infection and for those between 40 and 50 years, 30.7% (n = 65) still need vaccine protection. Across age groups there is a trend towards lower prevalence of hepatitis A virus antibody, in particular among youngsters, when compared with older Portuguese studies.

  16. Seasonal variation of maternally derived respiratory syncytial virus antibodies and association with infant hospitalizations for respiratory syncytial virus

    DEFF Research Database (Denmark)

    Stensballe, Lone Graff; Ravn, Henrik; Kristensen, Kim

    2009-01-01

    This study used 459 prospectively sampled cord blood samples to examine the association between maternally derived respiratory syncytial virus (RSV)-neutralizing antibodies and the RSV hospitalization season in Denmark. We found a clear temporal association and suggest that RSV-neutralizing antib......This study used 459 prospectively sampled cord blood samples to examine the association between maternally derived respiratory syncytial virus (RSV)-neutralizing antibodies and the RSV hospitalization season in Denmark. We found a clear temporal association and suggest that RSV......-neutralizing antibody level plays a role in the RSV seasonal pattern....

  17. Co-evolution of a broadly neutralizing HIV-1 antibody and founder virus

    Science.gov (United States)

    Liao, Hua-Xin; Lynch, Rebecca; Zhou, Tongqing; Gao, Feng; Alam, S. Munir; Boyd, Scott D.; Fire, Andrew Z.; Roskin, Krishna M.; Schramm, Chaim A.; Zhang, Zhenhai; Zhu, Jiang; Shapiro, Lawrence; Mullikin, James C.; Gnanakaran, S.; Hraber, Peter; Wiehe, Kevin; Kelsoe, Garnett; Yang, Guang; Xia, Shi-Mao; Montefiori, David C.; Parks, Robert; Lloyd, Krissey E.; Scearce, Richard M.; Soderberg, Kelly A.; Cohen, Myron; Kaminga, Gift; Louder, Mark K.; Tran, Lillan M.; Chen, Yue; Cai, Fangping; Chen, Sheri; Moquin, Stephanie; Du, Xiulian; Joyce, Gordon M.; Srivatsan, Sanjay; Zhang, Baoshan; Zheng, Anqi; Shaw, George M.; Hahn, Beatrice H.; Kepler, Thomas B.; Korber, Bette T.M.; Kwong, Peter D.; Mascola, John R.; Haynes, Barton F.

    2013-01-01

    Current HIV-1 vaccines elicit strain-specific neutralizing antibodies. However, cross-reactive neutralizing antibodies arise in ~20% of HIV-1-infected individuals, and details of their generation could provide a roadmap for effective vaccination. Here we report the isolation, evolution and structure of a broadly neutralizing antibody from an African donor followed from time of infection. The mature antibody, CH103, neutralized ~55% of HIV-1 isolates, and its co-crystal structure with gp120 revealed a novel loop-based mechanism of CD4-binding site recognition. Virus and antibody gene sequencing revealed concomitant virus evolution and antibody maturation. Notably, the CH103-lineage unmutated common ancestor avidly bound the transmitted/founder HIV-1 envelope glycoprotein, and evolution of antibody neutralization breadth was preceded by extensive viral diversification in and near the CH103 epitope. These data elucidate the viral and antibody evolution leading to induction of a lineage of HIV-1 broadly neutralizing antibodies and provide insights into strategies to elicit similar antibodies via vaccination. PMID:23552890

  18. Oncogenic Viruses and Breast Cancer: Mouse Mammary Tumor Virus (MMTV, Bovine Leukemia Virus (BLV, Human Papilloma Virus (HPV, and Epstein–Barr Virus (EBV

    Directory of Open Access Journals (Sweden)

    James S. Lawson

    2018-01-01

    Full Text Available BackgroundAlthough the risk factors for breast cancer are well established, namely female gender, early menarche and late menopause plus the protective influence of early pregnancy, the underlying causes of breast cancer remain unknown. The development of substantial recent evidence indicates that a handful of viruses may have a role in breast cancer. These viruses are mouse mammary tumor virus (MMTV, bovine leukemia virus (BLV, human papilloma viruses (HPVs, and Epstein–Barr virus (EBV-also known as human herpes virus type 4. Each of these viruses has documented oncogenic potential. The aim of this review is to inform the scientific and general community about this recent evidence.The evidenceMMTV and human breast cancer—the evidence is detailed and comprehensive but cannot be regarded as conclusive. BLV and human breast cancer—the evidence is limited. However, in view of the emerging information about BLV in human breast cancer, it is prudent to encourage the elimination of BLV in cattle, particularly in the dairy industry. HPVs and breast cancer—the evidence is substantial but not conclusive. The availability of effective preventive vaccines is a major advantage and their use should be encouraged. EBV and breast cancer—the evidence is also substantial but not conclusive. Currently, there are no practical means of either prevention or treatment. Although there is evidence of genetic predisposition, and cancer in general is a culmination of events, there is no evidence that inherited genetic traits are causal.ConclusionThe influence of oncogenic viruses is currently the major plausible hypothesis for a direct cause of human breast cancer.

  19. Oncogenic Viruses and Breast Cancer: Mouse Mammary Tumor Virus (MMTV), Bovine Leukemia Virus (BLV), Human Papilloma Virus (HPV), and Epstein-Barr Virus (EBV).

    Science.gov (United States)

    Lawson, James S; Salmons, Brian; Glenn, Wendy K

    2018-01-01

    Although the risk factors for breast cancer are well established, namely female gender, early menarche and late menopause plus the protective influence of early pregnancy, the underlying causes of breast cancer remain unknown. The development of substantial recent evidence indicates that a handful of viruses may have a role in breast cancer. These viruses are mouse mammary tumor virus (MMTV), bovine leukemia virus (BLV), human papilloma viruses (HPVs), and Epstein-Barr virus (EBV-also known as human herpes virus type 4). Each of these viruses has documented oncogenic potential. The aim of this review is to inform the scientific and general community about this recent evidence. MMTV and human breast cancer-the evidence is detailed and comprehensive but cannot be regarded as conclusive. BLV and human breast cancer-the evidence is limited. However, in view of the emerging information about BLV in human breast cancer, it is prudent to encourage the elimination of BLV in cattle, particularly in the dairy industry. HPVs and breast cancer-the evidence is substantial but not conclusive. The availability of effective preventive vaccines is a major advantage and their use should be encouraged. EBV and breast cancer-the evidence is also substantial but not conclusive. Currently, there are no practical means of either prevention or treatment. Although there is evidence of genetic predisposition, and cancer in general is a culmination of events, there is no evidence that inherited genetic traits are causal. The influence of oncogenic viruses is currently the major plausible hypothesis for a direct cause of human breast cancer.

  20. Human monoclonal antibodies derived from a patient infected with 2009 pandemic influenza A virus broadly cross-neutralize group 1 influenza viruses

    International Nuclear Information System (INIS)

    Pan, Yang; Sasaki, Tadahiro; Kubota-Koketsu, Ritsuko; Inoue, Yuji; Yasugi, Mayo; Yamashita, Akifumi; Ramadhany, Ririn; Arai, Yasuha; Du, Anariwa; Boonsathorn, Naphatsawan; Ibrahim, Madiha S.

    2014-01-01

    Highlights: • Influenza infection can elicit heterosubtypic antibodies to group 1 influenza virus. • Three human monoclonal antibodies were generated from an H1N1-infected patient. • The antibodies predominantly recognized α-helical stem of viral hemagglutinin (HA). • The antibodies inhibited HA structural activation during the fusion process. • The antibodies are potential candidates for future antibody therapy to influenza. - Abstract: Influenza viruses are a continuous threat to human public health because of their ability to evolve rapidly through genetic drift and reassortment. Three human monoclonal antibodies (HuMAbs) were generated in this study, 1H11, 2H5 and 5G2, and they cross-neutralize a diverse range of group 1 influenza A viruses, including seasonal H1N1, 2009 pandemic H1N1 (H1N1pdm) and avian H5N1 and H9N2. The three HuMAbs were prepared by fusing peripheral blood lymphocytes from an H1N1pdm-infected patient with a newly developed fusion partner cell line, SPYMEG. All the HuMAbs had little hemagglutination inhibition activity but had strong membrane-fusion inhibition activity against influenza viruses. A protease digestion assay showed the HuMAbs targeted commonly a short α-helix region in the stalk of the hemagglutinin. Furthermore, Ile45Phe and Glu47Gly double substitutions in the α-helix region made the HA unrecognizable by the HuMAbs. These two amino acid residues are highly conserved in the HAs of H1N1, H5N1 and H9N2 viruses. The HuMAbs reported here may be potential candidates for the development of therapeutic antibodies against group 1 influenza viruses

  1. Human monoclonal antibodies derived from a patient infected with 2009 pandemic influenza A virus broadly cross-neutralize group 1 influenza viruses

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Yang [Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); Sasaki, Tadahiro [Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); JST/JICA, Science and Technology Research Partnership for Sustainable Development (SATREPS), Tokyo (Japan); Kubota-Koketsu, Ritsuko [Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); Kanonji Institute, The Research Foundation for Microbial Diseases of Osaka University, Kanonji, Kagawa (Japan); JST/JICA, Science and Technology Research Partnership for Sustainable Development (SATREPS), Tokyo (Japan); Inoue, Yuji [Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); JST/JICA, Science and Technology Research Partnership for Sustainable Development (SATREPS), Tokyo (Japan); Yasugi, Mayo [Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Izumisano, Osaka (Japan); JST/JICA, Science and Technology Research Partnership for Sustainable Development (SATREPS), Tokyo (Japan); Yamashita, Akifumi; Ramadhany, Ririn; Arai, Yasuha [Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); Du, Anariwa [Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); JST/JICA, Science and Technology Research Partnership for Sustainable Development (SATREPS), Tokyo (Japan); Boonsathorn, Naphatsawan [Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); Department of Medical Sciences, Ministry of Public Health, Muang, Nonthaburi (Thailand); JST/JICA, Science and Technology Research Partnership for Sustainable Development (SATREPS), Tokyo (Japan); Ibrahim, Madiha S. [Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); Department of Microbiology and Immunology, Faculty of Veterinary Medicine, Damanhour University, Damanhour (Egypt); and others

    2014-07-18

    Highlights: • Influenza infection can elicit heterosubtypic antibodies to group 1 influenza virus. • Three human monoclonal antibodies were generated from an H1N1-infected patient. • The antibodies predominantly recognized α-helical stem of viral hemagglutinin (HA). • The antibodies inhibited HA structural activation during the fusion process. • The antibodies are potential candidates for future antibody therapy to influenza. - Abstract: Influenza viruses are a continuous threat to human public health because of their ability to evolve rapidly through genetic drift and reassortment. Three human monoclonal antibodies (HuMAbs) were generated in this study, 1H11, 2H5 and 5G2, and they cross-neutralize a diverse range of group 1 influenza A viruses, including seasonal H1N1, 2009 pandemic H1N1 (H1N1pdm) and avian H5N1 and H9N2. The three HuMAbs were prepared by fusing peripheral blood lymphocytes from an H1N1pdm-infected patient with a newly developed fusion partner cell line, SPYMEG. All the HuMAbs had little hemagglutination inhibition activity but had strong membrane-fusion inhibition activity against influenza viruses. A protease digestion assay showed the HuMAbs targeted commonly a short α-helix region in the stalk of the hemagglutinin. Furthermore, Ile45Phe and Glu47Gly double substitutions in the α-helix region made the HA unrecognizable by the HuMAbs. These two amino acid residues are highly conserved in the HAs of H1N1, H5N1 and H9N2 viruses. The HuMAbs reported here may be potential candidates for the development of therapeutic antibodies against group 1 influenza viruses.

  2. Genetic mapping of xenotropic murine leukemia virus-inducing loci in five mouse strains.

    Science.gov (United States)

    Kozak, C A; Rowe, W P

    1980-07-01

    A single mendelian gene was identified for induction of the endogenous xenotropic murine leukemia virus in five mouse strains (C57BL/10, C57L, C57BR, AKR, and BALB/c). This locus, designated Bxv-1, mapped to the same site on chromosome 1 in all strains: Id-1-Pep-3-[Bxv-1-Lp]. Thus, inducibility loci for xenotropic virus are more limited in number and chromosomal distribution than ecotropic inducibility loci. Virus expression in mice with Bxv-1 was induced by treatment of fibroblasts with 5-iododeoxyuridine or by exposure of spleen cells to a B cell mitogen, bacterial lipopolysaccharide. An analysis of the hamster X mouse somatic cell hybrids indicated that chromosome 1, alone, was sufficient for virus induction.

  3. Mechanisms in endogenous leukemia virus induction by radiation and chemicals

    International Nuclear Information System (INIS)

    Tennant, R.W.; Rascati, R.J.; Lavelle, G.C.

    1976-01-01

    A model of endogenous leukemia virus induction in AKR strain mouse cells based on two distinct types of alterations in cellular or proviral DNA is presented. The first type are non-repairable alterations, such as those caused by the incorporation of halogenated pyrimidines; the second type are repairable lesions, such as those caused by irradiation or certain other chemicals. The production of non-repairable lesions leads to the formation of a stable, proviral state which is dependent upon cell division for complete virus expression. A stable provirus intermediate state is not demonstrable in cells induced by treatments which cause repairable lesions, since replication of damaged or altered DNA must occur before the lesions are removed by repair synthesis. Experimental support for this model is presented

  4. Antibody Derived Peptides for Detection of Ebola Virus Glycoprotein.

    Directory of Open Access Journals (Sweden)

    Luis Mario Rodríguez-Martínez

    Full Text Available Current Ebola virus (EBOV detection methods are costly and impractical for epidemic scenarios. Different immune-based assays have been reported for the detection and quantification of Ebola virus (EBOV proteins. In particular, several monoclonal antibodies (mAbs have been described that bind the capsid glycoprotein (GP of EBOV GP. However, the currently available platforms for the design and production of full-length mAbs are cumbersome and costly. The use of antibody fragments, rather than full-length antibodies, might represent a cost-effective alternative for the development of diagnostic and possibly even therapeutic alternatives for EBOV.We report the design and expression of three recombinant anti-GP mAb fragments in Escherichia coli cultures. These fragments contained the heavy and light variable portions of the three well-studied anti-GP full-length mAbs 13C6, 13F6, and KZ52, and are consequently named scFv-13C6, scFv-13F6, and Fab-KZ52, respectively. All three fragments exhibited specific anti-GP binding activity in ELISA experiments comparable to that of full-length anti-GP antibodies (i.e., the same order of magnitude and they are easily and economically produced in bacterial cultures.Antibody fragments might represent a useful, effective, and low cost alternative to full-length antibodies in Ebola related capture and diagnostics applications.

  5. Increased expression of the regulatory T cell-associated marker CTLA-4 in bovine leukemia virus infection.

    Science.gov (United States)

    Suzuki, Saori; Konnai, Satoru; Okagawa, Tomohiro; Ikebuchi, Ryoyo; Nishimori, Asami; Kohara, Junko; Mingala, Claro N; Murata, Shiro; Ohashi, Kazuhiko

    2015-02-15

    Regulatory T cells (Tregs) play a critical role in the maintenance of the host's immune system. Tregs, particularly CD4(+)CD25(+)Foxp3(+) T cells, have been reported to be involved in the immune evasion mechanism of tumors and several pathogens that cause chronic infections. Recent studies showed that a Treg-associated marker, cytotoxic T-lymphocyte antigen 4 (CTLA-4), is closely associated with the progression of several diseases. We recently reported that the proportion of Foxp3(+)CD4(+) cells was positively correlated with the number of lymphocytes, virus titer, and virus load but inversely correlated with IFN-γ expression in cattle infected with bovine leukemia virus (BLV), which causes chronic infection and lymphoma in its host. Here the kinetics of CTLA-4(+) cells were analyzed in BLV-infected cattle. CTLA-4 mRNA was predominantly expressed in CD4(+) T cells in BLV-infected cattle, and the expression was positively correlated with Foxp3 mRNA expression. To test for differences in the protein expression level of CTLA-4, we measured the proportion of CTLA-4-expressing cells by flow cytometry. In cattle with persistent lymphocytosis (PL), mean fluorescence intensities (MFIs) of CTLA-4 on CD4(+) and CD25(+) T cells were significantly increased compared with that in control and aleukemic (AL) cattle. The percentage of CTLA-4(+) cells in the CD4(+) T cell subpopulation was positively correlated with TGF-β mRNA expression, suggesting that CD4(+)CTLA-4(+) T cells have a potentially immunosuppressive function in BLV infection. In the limited number of cattle that were tested, the anti-CTLA-4 antibody enhanced the expression of CD69, IL-2, and IFN-γ mRNA in anti-programmed death ligand 1 (PD-L1) antibody-treated peripheral blood mononuclear cells from BLV-infected cattle. Together with previous findings, the present results indicate that Tregs may be involved in the inhibition of T cell function during BLV infection. Copyright © 2014 Elsevier B.V. All rights

  6. In vitro and in vivo properties of human/mouse chimeric monoclonal antibody specific for common acute lymphocytic leukemia antigen

    International Nuclear Information System (INIS)

    Saga, T.; Endo, K.; Koizumi, M.; Kawamura, Y.; Watanabe, Y.; Konishi, J.; Ueda, R.; Nishimura, Y.; Yokoyama, M.; Watanabe, T.

    1990-01-01

    A human/mouse chimeric monoclonal antibody specific for a common acute lymphocytic leukemia antigen was efficiently obtained by ligating human heavy-chain enhancer element to the chimeric heavy- and light-chain genes. Cell binding and competitive inhibition assays of both radioiodine and indium-111- (111In) labeled chimeric antibodies demonstrated in vitro immunoreactivity identical with that of the parental murine monoclonal antibodies. The biodistribution of the radiolabeled chimeric antibody in tumor-bearing nude mice was similar to that of the parental murine antibody. Tumor accumulation of radioiodinated parental and chimeric antibodies was lower than that of 111 In-labeled antibodies, probably because of dehalogenation of the radioiodinated antibodies. Indium-111-labeled chimeric antibody clearly visualized xenografted tumor. These results suggest that a human/mouse chimeric antibody can be labeled with 111 In and radioiodine without the loss of its immunoreactivity, and that chimeric antibody localizes in vivo in the same way as the parental murine antibody

  7. Inactivated H7 Influenza Virus Vaccines Protect Mice despite Inducing Only Low Levels of Neutralizing Antibodies.

    Science.gov (United States)

    Kamal, Ram P; Blanchfield, Kristy; Belser, Jessica A; Music, Nedzad; Tzeng, Wen-Pin; Holiday, Crystal; Burroughs, Ashley; Sun, Xiangjie; Maines, Taronna R; Levine, Min Z; York, Ian A

    2017-10-15

    Avian influenza viruses of the H7 hemagglutinin (HA) subtype present a significant public health threat, as evidenced by the ongoing outbreak of human A(H7N9) infections in China. When evaluated by hemagglutination inhibition (HI) and microneutralization (MN) assays, H7 viruses and vaccines are found to induce lower level of neutralizing antibodies (nAb) than do their seasonal counterparts, making it difficult to develop and evaluate prepandemic vaccines. We have previously shown that purified recombinant H7 HA appear to be poorly immunogenic in that they induce low levels of HI and MN antibodies. In this study, we immunized mice with whole inactivated reverse genetics reassortant (RG) viruses expressing HA and neuraminidase (NA) from 3 different H7 viruses [A/Shanghai/2/2013(H7N9), A/Netherlands/219/2003(H7N7), and A/New York/107/2003(H7N2)] or with human A(H1N1)pdm09 (A/California/07/2009-like) or A(H3N2) (A/Perth16/2009) viruses. Mice produced equivalent titers of antibodies to all viruses as measured by enzyme-linked immunosorbent assay (ELISA). However, the antibody titers induced by H7 viruses were significantly lower when measured by HI and MN assays. Despite inducing very low levels of nAb, H7 vaccines conferred complete protection against homologous virus challenge in mice, and the serum antibodies directed against the HA head region were capable of mediating protection. The apparently low immunogenicity associated with H7 viruses and vaccines may be at least partly related to measuring antibody titers with the traditional HI and MN assays, which may not provide a true measure of protective immunity associated with H7 immunization. This study underscores the need for development of additional correlates of protection for prepandemic vaccines. IMPORTANCE H7 avian influenza viruses present a serious risk to human health. Preparedness efforts include development of prepandemic vaccines. For seasonal influenza viruses, protection is correlated with antibody

  8. Prevalence of Newcastle disease virus antibodies in sera and eggs ...

    African Journals Online (AJOL)

    ADEYEYE

    2016-03-07

    Mar 7, 2016 ... The seroprevalence and maternal antibody profiles to Newcastle disease virus infection of guinea fowls were studied using ..... gallisepticum. Avian diseases, 28 (4): 877-883. Sa'idu L, Tekdek LB & Abdu PA (2004). Prevalence of ND antibodies in domestic and semi domestic birds in Zaria, Nigeria.

  9. Radioinduced leukemia. An introduction to the study of experimental leukemia in mice

    International Nuclear Information System (INIS)

    Baudon, P.P.

    1974-01-01

    This thesis attempts to gain insight into any mechanisms involved in the onset of irradiation-induced leukemia in mice, then to show up the presence of a virus in the same animals. Concerning the mechanisms of radio-induced leukemias the pathogenic factors according to Kaplan are analysed: role of the thymus and cell mutation theory; lymphoid leukemias of extra-thymic origin; leukemogenesis co-factor; inhibiting action of the bone narrow. Evidence of the virus in mice was obtained by the use of electron microscopy, by inoculation. The contribution of experimental leukemia research is analysed, especially as it affects the therapeutic aspect. It is shown that in spite of setbacks in the most recent research on man, therapeutic trials on animals should be viewed from the angle of imminent human applications [fr

  10. Complement inhibition enables tumor delivery of LCMV glycoprotein pseudotyped viruses in the presence of antiviral antibodies

    Directory of Open Access Journals (Sweden)

    Laura Evgin

    2016-01-01

    Full Text Available The systemic delivery of therapeutic viruses, such as oncolytic viruses or vaccines, is limited by the generation of neutralizing antibodies. While pseudotyping of rhabdoviruses with the lymphocytic choriomeningitis virus glycoprotein has previously allowed for multiple rounds of delivery in mice, this strategy has not translated to other animal models. For the first time, we provide experimental evidence that antibodies generated against the lymphocytic choriomeningitis virus glycoprotein mediate robust complement-dependent viral neutralization via activation of the classical pathway. We show that this phenotype can be capitalized upon to deliver maraba virus pseudotyped with the lymphocytic choriomeningitis virus glycoprotein in a Fischer rat model in the face of neutralizing antibody through the use of complement modulators. This finding changes the understanding of the humoral immune response to arenaviruses, and also describes methodology to deliver viral vectors to their therapeutic sites of action without the interference of neutralizing antibody.

  11. Enhanced sensitivity in detection of antiviral antibody responses using biotinylation of foot-and-mouth disease virus (FMDV) capsids.

    Science.gov (United States)

    Kenney, Mary; Waters, Ryan A; Rieder, Elizabeth; Pega, Juan; Perez-Filguera, Mariano; Golde, William T

    2017-11-01

    Analysis of the immune response to infection of livestock by foot-and-mouth disease virus (FMDV) is most often reported as the serum antibody response to the virus. While measurement of neutralizing antibody has been sensitive and specific, measurements of the quality of the antibody response are less robust. Determining the immunoglobulin (Ig) isotype of the serum antibody response provides a deeper understanding of the biology of the response and more sensitive methods for these assays will facilitate analyses of B cell mediated immunity. We tested the hypothesis that using the virus as the molecular probe could be achieved by adding tags to the surface of the FMDV capsid, and that would enhance sensitivity in assays for anti-FMDV antibody responses. The use of a FLAG-tagged virus in these assays failed to yield improvement whereas chemically biotinylating the virus capsid resulted in significant enhancement of the signal. Here we describe methods using biotinylated virus for measuring anti-viral antibody in serum and antibody secreting cells (ASCs) in blood that are sensitive and specific. Finally, we describe using the biotinylated virus in flow cytometry where such assays should greatly enhance the analysis of anti-virus antibody producing B cells, allowing the investigator to focus on only the FMDV specific B cells when analyzing the development of the B cell response to either infection or vaccination. Published by Elsevier B.V.

  12. Immunoglobulin E antibodies to pollens augmented in dogs by virus vaccines.

    Science.gov (United States)

    Frick, O L; Brooks, D L

    1983-03-01

    An inbred "atopic dog colony" was established to study the effect of viruses on immunoregulation of immunoglobulin (Ig) E antibodies. Dogs were selected for high skin reactivity to grass and weed pollens. Their offspring were inoculated with pollen extracts in alum immediately after routine vaccinations (attenuated live-virus vaccines for canine distemper and infectious canine hepatitis, and a killed bacterin for Leptospira). Heat labile antipollen IgE antibodies were measured by passive cutaneous anaphylaxis. Pups vaccinated for canine distemper before being given pollen extracts had many more IgE antibodies than did their control littermates who were not vaccinated until after the last pollen extract injection. This may be a natural example of the "allergic break-through phenomenon."

  13. Specific antibodies to detect Tamarillo leaf malformation virus (TALMV) in Tamarillo

    International Nuclear Information System (INIS)

    Gallo Garcia, Yuliana; Marin Montoya, Mauricio; Gutierrez, Pablo Andres

    2011-01-01

    In Colombia, yields of Tamarillo are seriously affected by a complex viral disease known as virosis. This pathology was first reported in 1991 in the north of Antioquia and currently affects all Tamarillo growing regions in the country. Recent works have demonstrated the association of two potyviruses (potyviridae) with this disease: potato virus y (PVY) and Tamarillo leaf malformation virus (TALMV, proposed species). Specific diagnostic tools are required for early asymptomatic detection of these viruses and Tamarillo certification programs. In this study, we report the obtention of TALMV specific antibodies using a 15 residues peptide mimicking the n-terminal coat protein. Specificity and sensitivity of the anti-TALMV antibodies was determined by Elisa and dot-blot using recombinant protein and synthetic peptides as controls. The usefulness of these antibodies was validated from a preliminary trial of TALMV detection in plant samples obtained from Tamarillo crops in eastern Antioquia and results were compared with a TALMV specific coat RT-PCR detection protocol.

  14. [Evaluation of serum levels of tick-borne encephalitis (TBE) virus antibodies after administration of FSME inject vaccine].

    Science.gov (United States)

    Pancewicz, Sławomir A; Hermanowska-Szpakowicz, Teresa

    2002-01-01

    The purpose of this work was to evaluate the changes of anti-TBE virus antibodies serum concentration 3 months after administration of FSME Inject vaccine. The detection of IgG antibodies against TBE virus was performed in sera of 106 forest workers aged mean = 41.5. These sera were examined twice before and after vaccine administration using FSME Kombi-Kit. According to producer's information the "safe" concentration, which protects from TBE virus infection, is over 11VE. In examination 126 (24.5%) sera showed concentration of examined antibodies lower than 11 VE but in 80 (75.5%) sera antibodies concentration was from 12 to 47 VE (mean = 24.15 VE). In the examination 2 significant increase of antibodies concentration was stated. In all sera the concentration ranged from 9 to 62 VE (mean = 39.83 VE). The administration of TBE vaccine booster causes quick increase of antibodies against TBE virus to the level which is considered to be protective against TBE virus infection.

  15. Development and characterization of novel chimeric monoclonal antibodies for broad spectrum neutralization of rabies virus.

    Directory of Open Access Journals (Sweden)

    Pan Kyeom Kim

    Full Text Available Current post-exposure prophylaxis for rabies virus infection has several limitations in terms of supply, cost, safety, and efficacy. Attempts to replace human or equine rabies immune globulins (HRIG or ERIG have been made by several companies and institutes. We developed potent monoclonal antibodies to neutralize a broad spectrum of rabies viruses by screening hybridomas received from the U.S. Centers for Disease Control and Prevention (CDC. Two kinds of chimeric human antibodies (chimeric #7 and #17 were constructed by cloning the variable regions from selected hybridomas and the constant region of a human antibody. Two antibodies were bound to antigenic site III and I/IV, respectively, and were able to neutralize 51 field isolates of rabies virus that were isolated at different times and places such as Asia, Africa, North America, South America, and Australia. These two antibodies neutralize rabies viruses with high efficacy in an in vivo test using Syrian hamster and mouse models and show low risk for adverse immunogenicity.

  16. Development and characterization of novel chimeric monoclonal antibodies for broad spectrum neutralization of rabies virus.

    Science.gov (United States)

    Kim, Pan Kyeom; Keum, Sun Ju; Osinubi, Modupe O V; Franka, Richard; Shin, Ji Young; Park, Sang Tae; Kim, Man Su; Park, Mi Jung; Lee, Soo Young; Carson, William; Greenberg, Lauren; Yu, Pengcheng; Tao, Xiaoyan; Lihua, Wang; Tang, Qing; Liang, Guodong; Shampur, Madhusdana; Rupprecht, Charles E; Chang, Shin Jae

    2017-01-01

    Current post-exposure prophylaxis for rabies virus infection has several limitations in terms of supply, cost, safety, and efficacy. Attempts to replace human or equine rabies immune globulins (HRIG or ERIG) have been made by several companies and institutes. We developed potent monoclonal antibodies to neutralize a broad spectrum of rabies viruses by screening hybridomas received from the U.S. Centers for Disease Control and Prevention (CDC). Two kinds of chimeric human antibodies (chimeric #7 and #17) were constructed by cloning the variable regions from selected hybridomas and the constant region of a human antibody. Two antibodies were bound to antigenic site III and I/IV, respectively, and were able to neutralize 51 field isolates of rabies virus that were isolated at different times and places such as Asia, Africa, North America, South America, and Australia. These two antibodies neutralize rabies viruses with high efficacy in an in vivo test using Syrian hamster and mouse models and show low risk for adverse immunogenicity.

  17. TdT activity in acute myeloid leukemias defined by monoclonal antibodies.

    Science.gov (United States)

    San Miguel, J F; González, M; Cañizo, M C; Anta, J P; Portero, J A; López-Borrasca, A

    1986-09-01

    Blast cells from eight out of 71 patients diagnosed with acute myeloid leukemia (AML) by morphological, cytochemical, and immunological criteria showed TdT activity. Their distribution according to the FAB classification was one M1, one M2, one M4, two M5a, one M5b, one M6, and one undifferentiated case. The TdT+ AML cases did not show major clinical and hematological differences when compared with the classical TdT- AML patients. Other phenotypical aberrations in the expression of membrane antigens, apart from the presence of nuclear TdT, were not observed in these TdT+ cases after study with a large panel of monoclonal antibodies. A higher incidence of TdT+ cases was found among the monocytic variants of AML (M4 and M5)--four cases--than in the granulocytic variants (M1, M2, and M3)--2 cases. These TdT+ cases should be distinguished from mixed leukemias by double labeling techniques, assessing in the TdT+ AML the coexpression of TdT and myeloid markers in individual cells as shown in four of our cases.

  18. rapid assessment of polio virus antibodies prevalence amongst

    African Journals Online (AJOL)

    ISSN 1597-6343. Polio Virus Antibodies Prevalence Amongst Children In Kano State ... poliovirus serotypes (types 1, 2 or 3) which cause poliomyelitis. They are spread by ..... all those that have contributed to the overall success of this work.

  19. Prevalence of Antibodies Against Hepatitis e Virus in Veterinarians in Estonia

    DEFF Research Database (Denmark)

    Lassen, Brian; Janson, Marilin; Neare, Kädi

    2017-01-01

    positive with both tests. Antibody-positive samples were further examined for the presence of HEV RNA. Three (2.6%) of the 115 veterinarians tested positive for immunoglobulin G antibodies against HEV, whereas no immunoglobulin M antibodies against the virus were detected. The antibody......-positive veterinarians were small animal practitioners. Pigs comprised no or small part of their working time or patients. No HEV RNA was detected in the antibody-positive samples. The prevalence of antibodies against HEV in veterinarians in Estonia was lower than what has been observed in veterinarians in other...

  20. Evolution of Therapeutic Antibodies, Influenza Virus Biology, Influenza, and Influenza Immunotherapy

    Directory of Open Access Journals (Sweden)

    Urai Chaisri

    2018-01-01

    Full Text Available This narrative review article summarizes past and current technologies for generating antibodies for passive immunization/immunotherapy. Contemporary DNA and protein technologies have facilitated the development of engineered therapeutic monoclonal antibodies in a variety of formats according to the required effector functions. Chimeric, humanized, and human monoclonal antibodies to antigenic/epitopic myriads with less immunogenicity than animal-derived antibodies in human recipients can be produced in vitro. Immunotherapy with ready-to-use antibodies has gained wide acceptance as a powerful treatment against both infectious and noninfectious diseases. Influenza, a highly contagious disease, precipitates annual epidemics and occasional pandemics, resulting in high health and economic burden worldwide. Currently available drugs are becoming less and less effective against this rapidly mutating virus. Alternative treatment strategies are needed, particularly for individuals at high risk for severe morbidity. In a setting where vaccines are not yet protective or available, human antibodies that are broadly effective against various influenza subtypes could be highly efficacious in lowering morbidity and mortality and controlling unprecedented epidemic/pandemic. Prototypes of human single-chain antibodies to several conserved proteins of influenza virus with no Fc portion (hence, no ADE effect in recipients are available. These antibodies have high potential as a novel, safe, and effective anti-influenza agent.

  1. Polymerase chain reaction-based detection of myc transduction in feline leukemia virus-infected cats.

    Science.gov (United States)

    Sumi, Ryosuke; Miyake, Ariko; Endo, Taiji; Ohsato, Yoshiharu; Ngo, Minh Ha; Nishigaki, Kazuo

    2018-04-01

    Feline lymphomas are associated with the transduction and activation of cellular proto-oncogenes, such as c-myc, by feline leukemia virus (FeLV). We describe a polymerase chain reaction assay for detection of myc transduction usable in clinical diagnosis. The assay targets c-myc exons 2 and 3, which together result in a FeLV-specific fusion gene following c-myc transduction. When this assay was conducted on FeLV-infected feline tissues submitted for clinical diagnosis of tumors, myc transduction was detected in 14% of T-cell lymphoma/leukemias. This newly established system could become a useful diagnostic tool in veterinary medicine.

  2. Universal antibodies against the highly conserved influenza fusion peptide cross-neutralize several subtypes of influenza A virus

    Energy Technology Data Exchange (ETDEWEB)

    Hashem, Anwar M. [Centre for Vaccine Evaluation, Biologics and Genetic Therapies Directorate, HPFB, Health Canada, Ottawa, ON (Canada); Department of Microbiology, Faculty of Medicine, King Abdulaziz University, Jeddah (Saudi Arabia); Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON (Canada); Van Domselaar, Gary [National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB (Canada); Li, Changgui; Wang, Junzhi [National Institute for the Control of Pharmaceutical and Biological Products, Beijing (China); She, Yi-Min; Cyr, Terry D. [Centre for Vaccine Evaluation, Biologics and Genetic Therapies Directorate, HPFB, Health Canada, Ottawa, ON (Canada); Sui, Jianhua [Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, Department of Medicine, Harvard Medical School, 44 Binney Street, Boston, MA 02115 (United States); He, Runtao [National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB (Canada); Marasco, Wayne A. [Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, Department of Medicine, Harvard Medical School, 44 Binney Street, Boston, MA 02115 (United States); Li, Xuguang, E-mail: Sean.Li@hc-sc.gc.ca [Centre for Vaccine Evaluation, Biologics and Genetic Therapies Directorate, HPFB, Health Canada, Ottawa, ON (Canada); Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON (Canada)

    2010-12-10

    Research highlights: {yields} The fusion peptide is the only universally conserved epitope in all influenza viral hemagglutinins. {yields} Anti-fusion peptide antibodies are universal antibodies that cross-react with all influenza HA subtypes. {yields} The universal antibodies cross-neutralize different influenza A subtypes. {yields} The universal antibodies inhibit the fusion process between the viruses and the target cells. -- Abstract: The fusion peptide of influenza viral hemagglutinin plays a critical role in virus entry by facilitating membrane fusion between the virus and target cells. As the fusion peptide is the only universally conserved epitope in all influenza A and B viruses, it could be an attractive target for vaccine-induced immune responses. We previously reported that antibodies targeting the first 14 amino acids of the N-terminus of the fusion peptide could bind to virtually all influenza virus strains and quantify hemagglutinins in vaccines produced in embryonated eggs. Here we demonstrate that these universal antibodies bind to the viral hemagglutinins in native conformation presented in infected mammalian cell cultures and neutralize multiple subtypes of virus by inhibiting the pH-dependant fusion of viral and cellular membranes. These results suggest that this unique, highly-conserved linear sequence in viral hemagglutinin is exposed sufficiently to be attacked by the antibodies during the course of infection and merits further investigation because of potential importance in the protection against diverse strains of influenza viruses.

  3. Universal antibodies against the highly conserved influenza fusion peptide cross-neutralize several subtypes of influenza A virus

    International Nuclear Information System (INIS)

    Hashem, Anwar M.; Van Domselaar, Gary; Li, Changgui; Wang, Junzhi; She, Yi-Min; Cyr, Terry D.; Sui, Jianhua; He, Runtao; Marasco, Wayne A.; Li, Xuguang

    2010-01-01

    Research highlights: → The fusion peptide is the only universally conserved epitope in all influenza viral hemagglutinins. → Anti-fusion peptide antibodies are universal antibodies that cross-react with all influenza HA subtypes. → The universal antibodies cross-neutralize different influenza A subtypes. → The universal antibodies inhibit the fusion process between the viruses and the target cells. -- Abstract: The fusion peptide of influenza viral hemagglutinin plays a critical role in virus entry by facilitating membrane fusion between the virus and target cells. As the fusion peptide is the only universally conserved epitope in all influenza A and B viruses, it could be an attractive target for vaccine-induced immune responses. We previously reported that antibodies targeting the first 14 amino acids of the N-terminus of the fusion peptide could bind to virtually all influenza virus strains and quantify hemagglutinins in vaccines produced in embryonated eggs. Here we demonstrate that these universal antibodies bind to the viral hemagglutinins in native conformation presented in infected mammalian cell cultures and neutralize multiple subtypes of virus by inhibiting the pH-dependant fusion of viral and cellular membranes. These results suggest that this unique, highly-conserved linear sequence in viral hemagglutinin is exposed sufficiently to be attacked by the antibodies during the course of infection and merits further investigation because of potential importance in the protection against diverse strains of influenza viruses.

  4. Use of monoclonal antibodies against Hendra and Nipah viruses in an antigen capture ELISA

    Directory of Open Access Journals (Sweden)

    Spiropoulou Christina F

    2010-06-01

    Full Text Available Abstract Background Outbreaks of Hendra (HeV and Nipah (NiV viruses have been reported starting in 1994 and 1998, respectively. Both viruses are capable of causing fatal disease in humans and effecting great economical loss in the livestock industry. Results Through screening of hybridomas derived from mice immunized with γ-irradiated Nipah virus, we identified two secreted antibodies; one reactive with the nucleocapsid (N protein and the other, the phosphoprotein (P of henipaviruses. Epitope mapping and protein sequence alignments between NiV and HeV suggest the last 14 amino acids of the carboxyl terminus of the N protein is the target of the anti-N antibody. The anti-P antibody recognizes an epitope in the amino-terminal half of P protein. These monoclonal antibodies were used to develop two antigen capture ELISAs, one for virus detection and the other for differentiation between NiV and HeV. The lower limit of detection of the capture assay with both monoclonal antibodies was 400 pfu. The anti-N antibody was used to successfully detect NiV in a lung tissue suspension from an infected pig. Conclusion The antigen capture ELISA developed is potentially affordable tool to provide rapid detection and differentiation between the henipaviruses.

  5. Respiratory syncytial virus infection in infants with acute leukemia: a retrospective survey of the Japanese Pediatric Leukemia/Lymphoma Study Group.

    Science.gov (United States)

    Hatanaka, Michiki; Miyamura, Takako; Koh, Katsuyoshi; Taga, Takashi; Tawa, Akio; Hasegawa, Daisuke; Kajihara, Ryosuke; Adachi, Souichi; Ishii, Eiichi; Tomizawa, Daisuke

    2015-12-01

    Respiratory syncytial virus (RSV) can cause life-threatening complications of lower respiratory tract infection (LRTI) in young children with malignancies, but reports remain limited. We performed a retrospective nationwide survey to clarify the current status of RSV disease among infants with hematological malignancies. Clinical course, treatment, and outcome of patients with hematological malignancies who suffered from RSV infections at the age of acute leukemia were identified as having experienced RSV disease. The primary diseases were acute myeloid leukemia (n = 8) and acute lymphoblastic leukemia (n = 4). RSV infection occurred pre- or during induction therapy (n = 8) and during consolidation therapy (n = 4). Eight patients developed LRTI, four of whom had severe pneumonia or acute respiratory distress syndrome; these four patients died despite receiving intensive care. In our survey, the prognosis of RSV disease in pediatric hematological malignancies was poor, and progression of LRTI in particular was associated with high mortality. In the absence of RSV-specific therapy, effective prevention and treatment strategies for severe RSV disease must be investigated.

  6. Interplay of foot-and-mouth disease virus, antibodies and plasmacytoid dendritic cells: virus opsonization under non-neutralizing conditions results in enhanced interferon-alpha responses

    Directory of Open Access Journals (Sweden)

    Lannes Nils

    2012-08-01

    Full Text Available Abstract Foot-and-mouth disease virus (FMDV is a highly infectious member of the Picornaviridae inducing an acute disease of cloven-hoofed species. Vaccine-induced immune protection correlates with the presence of high levels of neutralizing antibodies but also opsonising antibodies have been proposed as an important mechanism of the immune response contributing to virus clearance by macrophages and leading to the production of type-I interferon (IFN by plasmacytoid dendritic cells (pDC. The present study demonstrates that the opsonising antibody titres mediating enhanced IFN-α responses in pDC were similar to neutralizing titres, when antigenically related viruses from the same serotype were employed. However, sera cross-reacted also with non-neutralized isolates of multiple serotypes, when tested in this assay. Both uncomplexed virus and immune complexed virus stimulated pDC via Toll-like receptor 7. An additional finding of potential importance for strain-specific differences in virulence and/or immunogenicity was that pDC activation by FMDV strongly differed between viral isolates. Altogether, our results indicate that opsonising antibodies can have a broader reactivity than neutralizing antibodies and may contribute to antiviral responses induced against antigenically distant viruses.

  7. Toxoplasma gondii, Dirofilaria immitis, feline immunodeficiency virus (FIV), and feline leukemia virus (FeLV) infections in stray and pet cats (Felis catus) in northwest China: co-infections and risk factors.

    Science.gov (United States)

    Cong, Wei; Meng, Qing-Feng; Blaga, Radu; Villena, Isabelle; Zhu, Xing-Quan; Qian, Ai-Dong

    2016-01-01

    This study was conducted to estimate the prevalence of Toxoplasma gondii, Dirofilaria immitis, feline immunodeficiency virus (FIV), and feline leukemia virus (FeLV) infections among stray and pet cats in Lanzhou, northwest China, and to identify the influence of age, gender, and regions on seropositivity. T. gondii antibodies were examined in cat sera by the modified agglutination test (MAT). The circulating antigens of D. immitis and FeLV and specific antibodies to FIV were examined using kits commercially available. The overall prevalence of T. gondii, FIV, FeLV, and D. immitis was 19.34, 9.12, 11.33, and 3.04 %, respectively. For the genetic characterization of T. gondii genotypes in cats, genomic DNA was extracted from the seropositive cats and the T. gondii B1 gene was amplified using a semi-nested PCR. DNA samples giving positive B1 amplification were then genotyped using multilocus PCR-RFLP. Two T. gondii genotypes (ToxoDB#9 and ToxoDB#1) were identified. Results of the multivariate logistic regression analysis showed that older cats are more likely to be seropositive than juveniles for T. gondii, FIV, FeLV, and D. immitis. This is the first report of T. gondii genotypes in cats in northwest China. Moreover, the present study is the first study of retrovirus and D. immitis seroprevalence in cats in China. The results revealed that T. gondii, FIV, and FeLV infections are common in stray and pet cats in northwest China.

  8. [IgM class antibodies against hepatitis A viruses in the differentiation of viral hepatitis].

    Science.gov (United States)

    Zivanović-Marinković, V; Stanković, D; Parabucki, S; Lazarov, A; Marinković, V; Krstić, L; Letica, Z

    1982-01-01

    The sera of 64 patients with acute viral hepatitis which were previously HbsAG negative by rPHA were tested by RIA methods for the presence of HBsAG and anti-HBc, by EIA method for HBc and anti-HBc and also by RIA method for the presence of IgM antibodies against hepatitis A virus. The pairs of sera were tested also for the presence of antibodies against cytomegalovirus and EB viruses. Of the total of 64 patients, markers of fresh HB viral infection were proved in 5 patients, sera positive to IgM antibodies to hepatitis A virus were found in 51 and no positive tests to any of the tested viruses were found in 8. The authors consider that they belonged to "non-A, non-B" viral hepatitis.

  9. A liquid phase blocking ELISA for the detection of antibodies against infectious bronchitis virus

    Directory of Open Access Journals (Sweden)

    Cardoso T.C.

    1999-01-01

    Full Text Available A liquid phase blocking ELISA (LPB-ELISA was developed for the detection and measurement of antibodies against infectious bronchitis virus (IBV. The purified and nonpurified virus used as antigen, the capture and detector antibodies, and the chicken hyperimmune sera were prepared and standardized for this purpose. A total of 156 sera from vaccinated and 100 from specific pathogen-free chickens with no recorded contact with the virus were tested. The respective serum titers obtained in the serum neutralization test (SNT were compared with those obtained in the LPB-ELISA. There was a high correlation (r2 = 0.8926 between the two tests. The LPB-ELISA represents a single test suitable for the rapid detection of antibodies against bronchitis virus in chicken sera, with good sensitivity (88%, specificity (100% and agreement (95.31%.

  10. The virion RNA species of the Kirsten murine sarcoma-leukemia virus complex released from a clonally related series of mouse cells

    International Nuclear Information System (INIS)

    Clewley, J.P.; Avery, R.J.

    1982-01-01

    We have characterized the virion RNA species of Kirsten sarcoma (KiSV) and Kirsten leukemia (KiLV) viruses released from a clonally related series of mouse cells (14). We have identified the KiLV and KiSV genome RNAs. In addition to the viral RNA species we find large amounts of a virus-like RNA (VL30 RNA), which is heterogeneous and shows variability in its expression. The amount of VL30 RNA in virions does not correlate with the state of transformation of the cells releasing the virus or the ability of the virus to transform other cells. Characterization of RNA rescued from non-producer cells has revealed a sarcoma virus (KiSVsub(SB3) with an oligonucleotide fingerprint different from that of a standard KiSV RNA, suggesting that it has lost some viral sequences. The oligonucleotide fingerprints of KiLV and VL30 RNAs are distinct from each other and from those reported for other murine leukemia virus RNAs. (Author)

  11. The Role of B Cells for in Vivo T Cell Responses to a Friend Virus-Induced Leukemia

    Science.gov (United States)

    Schultz, Kirk R.; Klarnet, Jay P.; Gieni, Randall S.; Hayglass, Kent T.; Greenberg, Philip D.

    1990-08-01

    B cells can function as antigen-presenting cells and accessory cells for T cell responses. This study evaluated the role of B cells in the induction of protective T cell immunity to a Friend murine leukemia virus (F-MuLV)-induced leukemia (FBL). B cell-deficient mice exhibited significantly reduced tumor-specific CD4^+ helper and CD8^+ cytotoxic T cell responses after priming with FBL or a recombinant vaccinia virus containing F-MuLV antigens. Moreover, these mice had diminished T cell responses to the vaccinia viral antigens. Tumor-primed T cells transferred into B cell-deficient mice effectively eradicated disseminated FBL. Thus, B cells appear necessary for efficient priming but not expression of tumor and viral T cell immunity.

  12. No benefit of therapeutic vaccination in clinically healthy cats persistently infected with feline leukemia virus.

    Science.gov (United States)

    Helfer-Hungerbuehler, A Katrin; Spiri, Andrea M; Riond, Barbara; Grest, Paula; Boretti, Felicitas S; Hofmann-Lehmann, Regina

    2015-03-24

    Therapeutic vaccinations have a potential application in infections where no curative treatment is available. In contrast to HIV, efficacious vaccines for a cat retrovirus, feline leukemia virus (FeLV), are commercially available. However, the infection is still prevalent, and no effective treatment of the infection is known. By vaccinating persistently FeLV-infected cats and presenting FeLV antigens to the immune system of the host, e.g., in the form of recombinant and/or adjuvanted antigens, we intended to shift the balance toward an advantage of the host so that persistent infection could be overcome by the infected cat. Two commercially available FeLV vaccines efficacious in protecting naïve cats from FeLV infection were tested in six experimentally and persistently FeLV-infected cats: first, a canarypox-vectored vaccine, and second, an adjuvanted, recombinant envelope vaccine was repeatedly administered with the aim to stimulate the immune system. No beneficial effects on p27 antigen and plasma viral RNA loads, anti-FeLV antibodies, or life expectancy of the cats were detected. The cats were unable to overcome or decrease viremia. Some cats developed antibodies to FeLV antigens although not protective. Thus, we cannot recommend vaccinating persistently FeLV-infected cats as a means of improving their FeLV status, quality of life or life expectancy. We suggest testing of all cats for FeLV infection prior to FeLV vaccination. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Murine Leukemia Virus (MLV)-based Coronavirus Spike-pseudotyped Particle Production and Infection

    Science.gov (United States)

    Millet, Jean Kaoru; Whittaker, Gary R.

    2016-01-01

    Viral pseudotyped particles (pp) are enveloped virus particles, typically derived from retroviruses or rhabdoviruses, that harbor heterologous envelope glycoproteins on their surface and a genome lacking essential genes. These synthetic viral particles are safer surrogates of native viruses and acquire the tropism and host entry pathway characteristics governed by the heterologous envelope glycoprotein used. They have proven to be very useful tools used in research with many applications, such as enabling the study of entry pathways of enveloped viruses and to generate effective gene-delivery vectors. The basis for their generation lies in the capacity of some viruses, such as murine leukemia virus (MLV), to incorporate envelope glycoproteins of other viruses into a pseudotyped virus particle. These can be engineered to contain reporter genes such as luciferase, enabling quantification of virus entry events upon pseudotyped particle infection with susceptible cells. Here, we detail a protocol enabling generation of MLV-based pseudotyped particles, using the Middle East respiratory syndrome coronavirus (MERS-CoV) spike (S) as an example of a heterologous envelope glycoprotein to be incorporated. We also describe how these particles are used to infect susceptible cells and to perform a quantitative infectivity readout by a luciferase assay. PMID:28018942

  14. Prevalence of African swine fever virus and classical swine fever virus antibodies in pigs in Benue State, Nigeria.

    Science.gov (United States)

    Asambe, A; Sackey, A K B; Tekdek, L B

    2018-03-01

    This study investigated the prevalence of African swine fever virus (ASFV) and classical swine fever virus (CSFV) antibodies in pigs in Benue State, Nigeria. Serum samples were collected from a total of 460 pigs, including 416 from 74 piggeries and 44 from Makurdi slaughter slab. The samples were analysed using indirect enzyme-linked immunosorbent assay (ELISA) test kit to detect the presence of ASFV antibodies, while competitive ELISA test kit was used to detect antibodies to CSFV. Our findings showed a total ASF prevalence of 13 (2.8%), while prevalences of 7 (1.7%) and 6 (13.6%) were observed in piggeries and in Makurdi slaughter slab, respectively. However, no CSFV antibody sera were detected in this study. Relatively higher ASFV antibody-positive pigs were detected in the slaughter slab than in piggeries. The difference in prevalence of ASF between the two locations was significantly associated (p = 0.017). These findings suggest the presence of ASFV antibody-positive pig in Benue State, Nigeria. Continuous surveillance and monitoring of these diseases among pigs in Nigeria to prevent any fulminating outbreak are recommended.

  15. Structure of a Human Astrovirus Capsid-Antibody Complex and Mechanistic Insights into Virus Neutralization

    Energy Technology Data Exchange (ETDEWEB)

    Bogdanoff, Walter A.; Campos, Jocelyn; Perez, Edmundo I.; Yin, Lu; Alexander, David L.; DuBois, Rebecca M. (UCSC)

    2016-11-02

    ABSTRACT

    Human astroviruses (HAstVs) are a leading cause of viral diarrhea in young children, the immunocompromised, and the elderly. There are no vaccines or antiviral therapies against HAstV disease. Several lines of evidence point to the presence of protective antibodies in healthy adults as a mechanism governing protection against reinfection by HAstV. However, development of anti-HAstV therapies is hampered by the gap in knowledge of protective antibody epitopes on the HAstV capsid surface. Here, we report the structure of the HAstV capsid spike domain bound to the neutralizing monoclonal antibody PL-2. The antibody uses all six complementarity-determining regions to bind to a quaternary epitope on each side of the dimeric capsid spike. We provide evidence that the HAstV capsid spike is a receptor-binding domain and that the antibody neutralizes HAstV by blocking virus attachment to cells. We identify patches of conserved amino acids that overlap the antibody epitope and may comprise a receptor-binding site. Our studies provide a foundation for the development of therapies to prevent and treat HAstV diarrheal disease.

    IMPORTANCEHuman astroviruses (HAstVs) infect nearly every person in the world during childhood and cause diarrhea, vomiting, and fever. Despite the prevalence of this virus, little is known about how antibodies in healthy adults protect them against reinfection. Here, we determined the crystal structure of a complex of the HAstV capsid protein and a virus-neutralizing antibody. We show that the antibody binds to the outermost spike domain of the capsid, and we provide evidence that the antibody blocks virus attachment to human cells. Importantly, our findings suggest that a subunit-based vaccine focusing the immune system on the HAstV capsid spike domain could be effective in protecting children against HAstV disease.

  16. PREVALENCE OF ANTIBODIES AGAINST INFLUENZA VIRUS IN NON-VACCINATED EQUINES FROM THE BRAZILIAN PANTANAL

    Directory of Open Access Journals (Sweden)

    Lucas Gaíva E Silva

    2014-12-01

    Full Text Available The prevalence of antibodies against Equine Influenza Virus (EIV was determined in 529 equines living on ranches in the municipality of Poconé, Pantanal area of Brazil, by means of the hemagglutination inhibition test, using subtype H3N8 as antigen. The distribution and possible association among positive animal and ranches were evaluated by the chi-square test, spatial autoregressive and multiple linear regression models. The prevalence of antibodies against EIV was estimated at 45.2% (95% CI 30.2 - 61.1% with titers ranging from 20 to 1,280 HAU. Seropositive equines were found on 92.0% of the surveyed ranches. Equine from non-flooded ranches (66.5% and negativity in equine infectious anemia virus (EIAV (61.7% were associated with antibodies against EIV. No spatial correlation was found among the ranches, but the ones located in non-flooded areas were associated with antibodies against EIV. A negative correlation was found between the prevalence of antibodies against EIV and the presence of EIAV positive animals on the ranches. The high prevalence of antibodies against EIV detected in this study suggests that the virus is circulating among the animals, and this statistical analysis indicates that the movement and aggregation of animals are factors associated to the transmission of the virus in the region.

  17. Single-Domain Antibodies as Tools to Perturb and Study RNA Viruses

    NARCIS (Netherlands)

    Hanke, Leo

    2017-01-01

    In this thesis, I describe the generation and characterization of alpaca-derived, antiviral, single-domain antibody fragments (VHHs). The antiviral targets of the described VHHs are the nuclear proteins of influenza A virus (IAV) and vesicular stomatitis virus (VSV). The described VHHs protect cells

  18. Enzyme-linked immunosorbent Assay for detecting of antibody to canine distemper virus

    Directory of Open Access Journals (Sweden)

    Sudarisman

    2006-03-01

    Full Text Available Serum neutralisation test (SNT has been established for evaluating canine distemper vaccination, but until now SNT was rarely used due to the need for continuous tissue culture facilities and requires 3 days to perform. For detecting antibody to canine distemper virus, an enzyme-linked immunosorbent assay (ELISA is relatively simple and rapid seroassay. ELISA for canine immunoglobulin (Ig G antibodies to canine distemper virus (CDV was developed by using Onderstepoort strain of canine distemper virus as coating antigen. Rabbit anti canine IgG labelled with horse radish peroxidase was used as the conjugate, while phenylenediamine dihydrochloride (OPD was used as the substrate. The ELISA results were then compared with the results of the SNT, using the sera of 312 random-source dogs from West Java. The two test-results had a high degree of correlation. Very few discrepancies occurred and most of these were at the lower limits of each test. When the sera were tested at 1 : 100 dilutions, there was a 95.5% agreement between the ELISA and SNT. Their sensitivity and spesificity were 83.9 and 98.4%. Titrated SNT and ELISA also were performed on sera from 7 dogs whose lifetime medical histories were known. The antibodies were inclining up after two months of post vaccination, where the titre was not in zero/lower position at the day of vaccination. However, antibody zero or low position were found at 28 days post vaccination. All of the results indicated that ELISA can be used for evaluating antibody to canine distemper virus response, replacing the SNT.

  19. Kinetics of Epstein-Barr Virus (EBV) Neutralizing and Virus-Specific Antibodies after Primary Infection with EBV

    Science.gov (United States)

    Bu, Wei; Hayes, Gregory M.; Liu, Hui; Gemmell, Lorraine; Schmeling, David O.; Radecki, Pierce; Aguilar, Fiona; Burbelo, Peter D.; Woo, Jennifer; Balfour, Henry H.

    2016-01-01

    Prospective studies of antibodies to multiple Epstein-Barr virus (EBV) proteins and EBV neutralizing antibodies in the same individuals before, during, and after primary EBV infection have not been reported. We studied antibody responses to EBV in college students who acquired primary EBV infection during prospective surveillance and correlated the kinetics of antibody response with the severity of disease. Neutralizing antibodies and enzyme-linked immunosorbent assay (ELISA) antibodies to gp350, the major target of neutralizing antibody, reached peak levels at medians of 179 and 333 days after the onset of symptoms of infectious mononucleosis, respectively. No clear correlation was found between the severity of the symptoms of infectious mononucleosis and the peak levels of antibody to individual viral proteins or to neutralizing antibody. In summary, we found that titers of neutralizing antibody and antibodies to multiple EBV proteins increase over many months after primary infection with EBV. PMID:26888186

  20. A comparison of labelled antibody methods for the detection of virus antigens in cell monolayers

    International Nuclear Information System (INIS)

    Oram, J.D.; Crooks, A.J.

    1979-01-01

    A number of labelled antibody methods have been applied to the detection of Semliki Forest virus antigens after replication of the virus in monolayers of host cells in multi-well polystyrene plates. The importance of several reaction variables has been investigated and the sensitivity of the methods compared for different periods of virus replication. Direct assays with radio-labelled antibody (RLA) and indirect assays peroxidase-antiperoxidase complexes (PAP) were equally sensitive. Direct and indirect assays using enzyme-linked antibodies (ELA) were slightly less sensitive than the direct RLA and PAP methods but were more sensitive than the indirect RLA or fluorescent antibody (FLA) methods. Direct assays using ELA were more rapid and easier to perform than the other assay methods. (Auth.)

  1. Mechanism of infectivity of a murine leukemia virus in adult mice

    International Nuclear Information System (INIS)

    Levy, R.L.; Barrington, M.H.; Lerner, R.A.; Dixon, F.J.

    1976-01-01

    Infection of adult BALB/c mice with murine leukemia virus (MuLV) induces typical thymic lymphomas. Expression of virus was measured by using a radioimmunoassay for murine P-30, a virion core protein. Nineteen days after injection of MuLV-S into adult mice, there were 0.3μg P-30/ml of serum. X-irradiation permitted the early expression of high levels of viremia, when given before or after MuLV-S administration, and it also hastened the development of lymphomas. Seventeen to 21 days after injection of MuLV-S into x-irradiated (600 rads) adult mice, there were 2.7 μg of P-30/ml of serum. The virus produced by infected adult mice was infectious and oncogenic when given to newborn mice. Several lines of evidence are presented that suggest the mechanism by which x-irradiation permits early expession of virion proteins and lymphomas is not immunosuppression

  2. A monoclonal antibody to inclusion body disease of cranes virus enabling specific immunohistochemistry and competitive ELISA

    Science.gov (United States)

    Letchworth, G.J.; Fishel, J.R.; Hansen, W.R.

    1997-01-01

    Inclusion body disease of cranes (IBDC) herpesvirus kills some infected cranes and persists in convalescent animals. To enable further study and rapid identification of carrier animals, we developed a monoclonal antibody (MAb) to IBDC virus and used it in immunohistochemistry and a competitive enzyme-linked immunosorbent assay (ELISA). We used conventional techniques to make murine MAbs directed against IBDC virus purified from infected duck embryo cells. Hybridomas reacting in an ELISA with IBDC virus but not uninfected duck embryo cells were characterized by radioimmunoprecipitation, in situ immunohistochemistry, and competitive ELISA with neutralizing and nonneutralizing crane sera. MAb 2C11 immunoprecipitated 59-, 61-, and 110-kD proteins from IBDC virus-infected but not uninfected cells and stained glutaraldehyde-fixed IBDC virus plaques but not surrounding uninfected duck embryo cells in vitro. Antibody 2C11 did not react with duck embryo cells infected with falcon herpesvirus, psittacine herpesvirus, infectious laryngotracheitis, pigeon herpesvirus, or duck plague virus. A competitive ELISA using antibody 2C11 identified most sera that were positive in the neutralization test. This antibody will be useful in further characterizing IBDC virus, its pathogenesis, and its natural history.

  3. Targeting connective tissue growth factor (CTGF) in acute lymphoblastic leukemia preclinical models: anti-CTGF monoclonal antibody attenuates leukemia growth.

    Science.gov (United States)

    Lu, Hongbo; Kojima, Kensuke; Battula, Venkata Lokesh; Korchin, Borys; Shi, Yuexi; Chen, Ye; Spong, Suzanne; Thomas, Deborah A; Kantarjian, Hagop; Lock, Richard B; Andreeff, Michael; Konopleva, Marina

    2014-03-01

    Connective tissue growth factor (CTGF/CCN2) is involved in extracellular matrix production, tumor cell proliferation, adhesion, migration, and metastasis. Recent studies have shown that CTGF expression is elevated in precursor B-acute lymphoblastic leukemia (ALL) and that increased expression of CTGF is associated with inferior outcome in B-ALL. In this study, we characterized the functional role and downstream signaling pathways of CTGF in ALL cells. First, we utilized lentiviral shRNA to knockdown CTGF in RS4;11 and REH ALL cells expressing high levels of CTGF mRNA. Silencing of CTGF resulted in significant suppression of leukemia cell growth compared to control vector, which was associated with AKT/mTOR inactivation and increased levels of cyclin-dependent kinase inhibitor p27. CTGF knockdown sensitized ALL cells to vincristine and methotrexate. Treatment with an anti-CTGF monoclonal antibody, FG-3019, significantly prolonged survival of mice injected with primary xenograft B-ALL cells when co-treated with conventional chemotherapy (vincristine, L-asparaginase and dexamethasone). Data suggest that CTGF represents a targetable molecular aberration in B-ALL, and blocking CTGF signaling in conjunction with administration of chemotherapy may represent a novel therapeutic approach for ALL patients.

  4. Microculture system for detection of Newcastle disease virus antibodies.

    Science.gov (United States)

    Wooley, R E; Brown, J; Gratzek, J B; Kleven, S H; Scott, T A

    1974-05-01

    A microculture system utilizing cytopathic effect (CPE) and hemadsorption (HAd) end points was effective in determining the level of Newcastle disease virus (NDV) antibodies. The microculture system was of comparable sensitivity to the plaque reduction test for the detection of NDV antibodies. The standards by which the CPE and HAd microculture tests would be considered reproducible were defined. The results indicate that the CPE and HAd microculture tests are reproducible within one twofold dilution.

  5. Separation of hemagglutination-inhibiting immunoglobulin M antibody to rubella virus in human serum by high-performance liquid chromatography.

    OpenAIRE

    Kobayashi, N; Suzuki, M; Nakagawa, T; Matumoto, M

    1986-01-01

    High-performance liquid chromatography was successfully used to separate hemagglutination-inhibiting immunoglobulin M (IgM) rubella virus antibody from IgG rubella virus antibody in human serum. The fractionation by high-performance liquid chromatography was as effective as sucrose density gradient centrifugation in separating IgM antibody from IgG antibody.

  6. Genetic diversity in the feline leukemia virus gag gene.

    Science.gov (United States)

    Kawamura, Maki; Watanabe, Shinya; Odahara, Yuka; Nakagawa, So; Endo, Yasuyuki; Tsujimoto, Hajime; Nishigaki, Kazuo

    2015-06-02

    Feline leukemia virus (FeLV) belongs to the Gammaretrovirus genus and is horizontally transmitted among cats. FeLV is known to undergo recombination with endogenous retroviruses already present in the host during FeLV-subgroup A infection. Such recombinant FeLVs, designated FeLV-subgroup B or FeLV-subgroup D, can be generated by transduced endogenous retroviral env sequences encoding the viral envelope. These recombinant viruses have biologically distinct properties and may mediate different disease outcomes. The generation of such recombinant viruses resulted in structural diversity of the FeLV particle and genetic diversity of the virus itself. FeLV env diversity through mutation and recombination has been studied, while gag diversity and its possible effects are less well understood. In this study, we investigated recombination events in the gag genes of FeLVs isolated from naturally infected cats and reference isolates. Recombination and phylogenetic analyses indicated that the gag genes often contain endogenous FeLV sequences and were occasionally replaced by entire endogenous FeLV gag genes. Phylogenetic reconstructions of FeLV gag sequences allowed for classification into three distinct clusters, similar to those previously established for the env gene. Analysis of the recombination junctions in FeLV gag indicated that these variants have similar recombination patterns within the same genotypes, indicating that the recombinant viruses were horizontally transmitted among cats. It remains to be investigated whether the recombinant sequences affect the molecular mechanism of FeLV transmission. These findings extend our understanding of gammaretrovirus evolutionary patterns in the field. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. No evidence of murine leukemia virus-related viruses in live attenuated human vaccines.

    Directory of Open Access Journals (Sweden)

    William M Switzer

    Full Text Available The association of xenotropic murine leukemia virus (MLV-related virus (XMRV in prostate cancer and chronic fatigue syndrome reported in previous studies remains controversial as these results have been questioned by recent data. Nonetheless, concerns have been raised regarding contamination of human vaccines as a possible source of introduction of XMRV and MLV into human populations. To address this possibility, we tested eight live attenuated human vaccines using generic PCR for XMRV and MLV sequences. Viral metagenomics using deep sequencing was also done to identify the possibility of other adventitious agents.All eight live attenuated vaccines, including Japanese encephalitis virus (JEV (SA-14-14-2, varicella (Varivax, measles, mumps, and rubella (MMR-II, measles (Attenuvax, rubella (Meruvax-II, rotavirus (Rotateq and Rotarix, and yellow fever virus were negative for XMRV and highly related MLV sequences. However, residual hamster DNA, but not RNA, containing novel endogenous gammaretrovirus sequences was detected in the JEV vaccine using PCR. Metagenomics analysis did not detect any adventitious viral sequences of public health concern. Intracisternal A particle sequences closest to those present in Syrian hamsters and not mice were also detected in the JEV SA-14-14-2 vaccine. Combined, these results are consistent with the production of the JEV vaccine in Syrian hamster cells.We found no evidence of XMRV and MLV in eight live attenuated human vaccines further supporting the safety of these vaccines. Our findings suggest that vaccines are an unlikely source of XMRV and MLV exposure in humans and are consistent with the mounting evidence on the absence of these viruses in humans.

  8. Indirect micro-immunofluorescence test for detecting type-specific antibodies to herpes simplex virus.

    Science.gov (United States)

    Forsey, T; Darougar, S

    1980-02-01

    A rapid indirect micro-immunofluorescence test capable of detecting and differentiating type-specific antibodies to herpes simplex virus is described. The test proved highly sensitive and, in 80 patients with active herpes ocular infection, antibody was detected in 94%. No anti-herpes antibody was detected in a control group of 20 patients with adenovirus infections. Testing of animal sera prepared against herpes simplex virus types 1 and 2 and of human sera from cases of ocular and genital herpes infections showed that the test can differentiate antibodies to the infecting serotypes. Specimens of whole blood, taken by fingerprick, and eye secretions, both collected on cellulose sponges, could be tested by indirect micro-immunofluorescence. Anti-herpes IgG, IgM, and IgA can also be detected.

  9. Macrophage and NK-mediated killing of precursor-B acute lymphoblastic leukemia cells targeted with a-fucosylated anti-CD19 humanized antibodies.

    Science.gov (United States)

    Matlawska-Wasowska, K; Ward, E; Stevens, S; Wang, Y; Herbst, R; Winter, S S; Wilson, B S

    2013-06-01

    This work reports the tumoricidal effects of a novel investigational humanized anti-CD19 monoclonal antibody (Medi-551). An a-fucosylated antibody with increased affinity for human FcγRIIIA, Medi-551 is shown to mediate both antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP). Medi-551/CD19 complexes internalize slowly (>5 h) and thus remain accessible to effector cells for prolonged periods. We evaluated in vitro ADCC and ADCP activities of primary human natural killer (NK) cells and macrophages against precursor-B (pre-B) acute lymphoblastic leukemia (ALL) cell lines and pediatric patient blasts. Fluorescent imaging studies document immunological synapses formed between anti-CD19-bound target leukemia cells and effector cells and capture the kinetics of both NK-mediated killing and macrophage phagocytosis. Genetic polymorphisms in FcγRIIIA-158F/V modulate in vitro activities of effector cells, with FcγRIIIA-158V homozygotes or heterozygotes showing the strongest activity. Medi-551 treatment of severe combined immunodeficiency (SCID) mice engrafted with human pre-B cells led to prolonged animal survival and markedly reduced disease burden in blood, liver and bone marrow. These data show that anti-CD19 antibodies effectively recruit immune cells to pre-B ALL cells and support a move forward to early phase trials in this disease.

  10. Monitoring of Antibodies Titre Against Canine Distemper Virus in Ferrets Vaccinated with a Live Modified Vaccine

    Directory of Open Access Journals (Sweden)

    L. Pavlačík

    2007-01-01

    Full Text Available A group of five ferrets vaccinated against the canine distemper virus (CDV was evaluated as to the onset of anti-CDV antibody production and the serum levels of the animals were monitored for one year. The ferrets were immunized with a live attenuated vaccine. The vaccination pattern was as follows: primary vaccination at the age of 6 weeks, fi rst revaccination at 30 days after primary vaccination, and second revaccination after another 30 days. Blood samples were taken prior to primary vaccination and then at 30-day intervals (sampling 1 to 12. The whole experimental cycle covered the period of one year from primary vaccination (till the age of 1 year and 6 weeks. Serum samples were analysed for anti-CDV virus-neutralisation antibodies using a virus-neutralisation test using the Onderstepoort CDV strain. All ferrets had zero virus-neutralisation antibody titres before primary vaccination. Two ferrets produced virus-neutralisation antibodies as a response to first revaccination. A stable antibody level (titre 256 was maintained between months 4 and 11 after primary vaccination and a sudden increase in antibody titre (titres 512 and 1024 - 2048 occurred in both animals in months 11 and 12. The reason for the abrupt rise in antibody titres in the two animals remains unclear. No anti-CDV seroconversion was observed in the three remaining animals. Regarding the results obtained in this study we do not consider commonly recommended vaccination with a live attenuated anti-CDV vaccine as an effective method of antibodies induction against distemper in young ferrets.

  11. Pichia pastoris-Expressed Bivalent Virus-Like Particulate Vaccine Induces Domain III-Focused Bivalent Neutralizing Antibodies without Antibody-Dependent Enhancement in Vivo

    Directory of Open Access Journals (Sweden)

    Rahul Shukla

    2018-01-01

    Full Text Available Dengue, a significant public health problem in several countries around the world, is caused by four different serotypes of mosquito-borne dengue viruses (DENV-1, -2, -3, and -4. Antibodies to any one DENV serotype which can protect against homotypic re-infection, do not offer heterotypic cross-protection. In fact, cross-reactive antibodies may augment heterotypic DENV infection through antibody-dependent enhancement (ADE. A recently launched live attenuated vaccine (LAV for dengue, which consists of a mixture of four chimeric yellow-fever/dengue vaccine viruses, may be linked to the induction of disease-enhancing antibodies. This is likely related to viral interference among the replicating viral strains, resulting in an unbalanced immune response, as well as to the fact that the LAV encodes prM, a DENV protein documented to elicit ADE-mediating antibodies. This makes it imperative to explore the feasibility of alternate ADE risk-free vaccine candidates. Our quest for a non-replicating vaccine centered on the DENV envelope (E protein which mediates virus entry into the host cell and serves as an important target of the immune response. Serotype-specific neutralizing epitopes and the host receptor recognition function map to E domain III (EDIII. Recently, we found that Pichia pastoris-expressed DENV E protein, of all four serotypes, self-assembled into virus-like particles (VLPs in the absence of prM. Significantly, these VLPs displayed EDIII and elicited EDIII-focused DENV-neutralizing antibodies in mice. We now report the creation and characterization of a novel non-replicating recombinant particulate vaccine candidate, produced by co-expressing the E proteins of DENV-1 and DENV-2 in P. pastoris. The two E proteins co-assembled into bivalent mosaic VLPs (mVLPs designated as mE1E2bv VLPs. The mVLP, which preserved the serotype-specific antigenic integrity of its two component proteins, elicited predominantly EDIII-focused homotypic virus

  12. Canine distemper virus DNA vaccination of mink can overcome interference by maternal antibodies.

    Science.gov (United States)

    Jensen, Trine Hammer; Nielsen, Line; Aasted, Bent; Pertoldi, Cino; Blixenkrone-Møller, Merete

    2015-03-10

    Canine distemper virus (CDV) is highly contagious and can cause severe disease against which conventional live vaccines are ineffective in the presence of maternal antibodies. Vaccination in the presences of maternal antibodies was challenged by vaccination of 5 days old and 3 weeks old mink kits with CDV DNA vaccines. Virus neutralising (VN) antibody responses were induced in mink kits vaccinated with a plasmid encoding the haemaglutinin protein (H) of CDV (n=5, pCDV-H) or a combination of the H, fusion (F) and nucleoprotein (N) of CDV (n=5, pCDV-HFN). These DNA vaccinated kits were protected against virulent experimental infection with field strains of CDV. The pCDV-H was more efficient in inducing protective immunity in the presence of maternal antibodies compared to the pCDV-HFN. The results show that DNA vaccination with the pCDV-H or pCDV-HFN (n=4) only given once at 5 days of age induces virus specific immune response in neonatal mink and protection against virulent CDV exposure later in life. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Hepatitis c virus antibodies in mother-infant blood pair in Zaria

    African Journals Online (AJOL)

    2017-06-01

    Jun 1, 2017 ... Abstract: Objectives: To deter- mine the prevalence of Hepatitis. C virus (HCV) antibodies in mother-infant pair, and risk fac- tors for vertical transmission of. HCV in ABUTH Zaria. Method: One hundred mother- infant pair had serological deter- mination for HCV antibodies from birth to 28days and a repeat.

  14. Antibodies to H5 subtype avian influenza virus and Japanese encephalitis virus in northern pintails (Anas acuta) sampled in Japan

    Science.gov (United States)

    Ramey, Andy M.; Spackman, Erica; Yeh, Jung-Yong; Fujita, Go; Konishi, Kan; Reed, John A.; Wilcox, Benjamin R.; Brown, Justin D.; Stallknecht, David E.

    2013-01-01

    Blood samples from 105 northern pintails (Anas acuta) captured on Hokkaido, Japan were tested for antibodies to avian influenza virus (AIV), Japanese encephalitis virus (JEV), and West Nile virus (WNV) to assess possible involvement of this species in the spread of economically important and potentially zoonotic pathogens. Antibodies to AIV were detected in 64 of 105 samples (61%). Of the 64 positives, 95% and 81% inhibited agglutination of two different H5 AIV antigens (H5N1 and H5N9), respectively. Antibodies to JEV and WNV were detected in five (5%) and none of the samples, respectively. Results provide evidence for prior exposure of migrating northern pintails to H5 AIV which couldhave implications for viral shedding and disease occurrence. Results also provide evidence for limited involvement of this species in the transmission and spread of flaviviruses during spring migration.

  15. Seroprevalence of hepatitis C virus antibodies amongst blood ...

    African Journals Online (AJOL)

    Background: Hepatitis C virus (HCV) is one of the most common transfusion transmissible infections hence the introduction of routine screening for its antibodies in blood donors in most blood banks. Methods: This was a retrospective study in which the blood donor screening register for all intending donors were reviewed ...

  16. Feline immunodeficiency virus and feline leukemia virus: frequency and associated factors in cats in northeastern Brazil.

    Science.gov (United States)

    Lacerda, L C; Silva, A N; Freitas, J S; Cruz, R D S; Said, R A; Munhoz, A D

    2017-05-10

    Our aims were to determine the frequencies of feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) in owned and stray cats in the northeastern region of Brazil, ascertain the status of FeLV infection, and investigate potential associated factors among the owned cats. Blood samples from 200 asymptomatic owned cats and 30 stray cats were processed using nested PCR and commercial immunochromatographic tests to diagnose infections. To evaluate the factors associated with FIV and/or FeLV in owned cats, a semi-structured interview was conducted with each owner about the animal's environment, and these data were subjected to unconditional logistic regression. The frequencies for owned cats were 6% (12/200) and 3% (6/200) for FIV and FeLV, respectively. No owned cat was positive for both viruses. Stray cats showed frequencies of 6.66% (2/30) and 0% (0/30) for FIV and FeLV, respectively. Contact with other cats and living in peri-urban areas were considered to be risk factors (P feline population more accurately, particularly with regard to infections by FeLV, which have complex pathogenesis.

  17. Bovine leukemia virus nucleocapsid protein is an efficient nucleic acid chaperone

    International Nuclear Information System (INIS)

    Qualley, Dominic F.; Sokolove, Victoria L.; Ross, James L.

    2015-01-01

    Nucleocapsid proteins (NCs) direct the rearrangement of nucleic acids to form the most thermodynamically stable structure, and facilitate many steps throughout the life cycle of retroviruses. NCs bind strongly to nucleic acids (NAs) and promote NA aggregation by virtue of their cationic nature; they also destabilize the NA duplex via highly structured zinc-binding motifs. Thus, they are considered to be NA chaperones. While most retroviral NCs are structurally similar, differences are observed both within and between retroviral genera. In this work, we compare the NA binding and chaperone activity of bovine leukemia virus (BLV) NC to that of two other retroviral NCs: human immunodeficiency virus type 1 (HIV-1) NC, which is structurally similar to BLV NC but from a different retrovirus genus, and human T-cell leukemia virus type 1 (HTLV-1) NC, which possesses several key structural differences from BLV NC but is from the same genus. Our data show that BLV and HIV-1 NCs bind to NAs with stronger affinity in relation to HTLV-1 NC, and that they also accelerate the annealing of complementary stem-loop structures to a greater extent. Analysis of kinetic parameters derived from the annealing data suggests that while all three NCs stimulate annealing by a two-step mechanism as previously reported, the relative contributions of each step to the overall annealing equilibrium are conserved between BLV and HIV-1 NCs but are different for HTLV-1 NC. It is concluded that while BLV and HTLV-1 belong to the same genus of retroviruses, processes that rely on NC may not be directly comparable. - Highlights: • BLV NC binds strongly to DNA and RNA. • BLV NC promotes mini-TAR annealing as well as HIV-1 NC. • Annealing kinetics suggest a low degree of similarity between BLV NC and HTLV-1 NC

  18. Bovine leukemia virus nucleocapsid protein is an efficient nucleic acid chaperone

    Energy Technology Data Exchange (ETDEWEB)

    Qualley, Dominic F., E-mail: dqualley@berry.edu; Sokolove, Victoria L.; Ross, James L.

    2015-03-13

    Nucleocapsid proteins (NCs) direct the rearrangement of nucleic acids to form the most thermodynamically stable structure, and facilitate many steps throughout the life cycle of retroviruses. NCs bind strongly to nucleic acids (NAs) and promote NA aggregation by virtue of their cationic nature; they also destabilize the NA duplex via highly structured zinc-binding motifs. Thus, they are considered to be NA chaperones. While most retroviral NCs are structurally similar, differences are observed both within and between retroviral genera. In this work, we compare the NA binding and chaperone activity of bovine leukemia virus (BLV) NC to that of two other retroviral NCs: human immunodeficiency virus type 1 (HIV-1) NC, which is structurally similar to BLV NC but from a different retrovirus genus, and human T-cell leukemia virus type 1 (HTLV-1) NC, which possesses several key structural differences from BLV NC but is from the same genus. Our data show that BLV and HIV-1 NCs bind to NAs with stronger affinity in relation to HTLV-1 NC, and that they also accelerate the annealing of complementary stem-loop structures to a greater extent. Analysis of kinetic parameters derived from the annealing data suggests that while all three NCs stimulate annealing by a two-step mechanism as previously reported, the relative contributions of each step to the overall annealing equilibrium are conserved between BLV and HIV-1 NCs but are different for HTLV-1 NC. It is concluded that while BLV and HTLV-1 belong to the same genus of retroviruses, processes that rely on NC may not be directly comparable. - Highlights: • BLV NC binds strongly to DNA and RNA. • BLV NC promotes mini-TAR annealing as well as HIV-1 NC. • Annealing kinetics suggest a low degree of similarity between BLV NC and HTLV-1 NC.

  19. Association of the leukemia inhibitory factor gene mutation and the antiphospholipid antibodies in the peripheral blood of infertile women

    Czech Academy of Sciences Publication Activity Database

    Králíčková, M.; Ulčová-Gallová, Z.; Šíma, R.; Vaněček, T.; Šíma, Petr; Křižan, Jiří; Suchá, J.; Uher, P.; Hes, O.; Novotný, Z.; Rokyta, Z.; Větvička, E.

    2007-01-01

    Roč. 52, č. 5 (2007), s. 543-548 ISSN 0015-5632 R&D Projects: GA ČR GA301/05/0078 Institutional research plan: CEZ:AV0Z50200510 Keywords : leukemia inhibitory faktor * lif gene mutation * antiphospholipid antibodies Subject RIV: EE - Microbiology, Virology Impact factor: 0.989, year: 2007

  20. Diagnostic performances of two rapid tests for detection of feline leukemia virus antigen in sera of experimentally feline leukemia virus-infected cats

    Directory of Open Access Journals (Sweden)

    Matthew R Krecic

    2017-12-01

    Full Text Available Objectives The objective of this study was to compare the diagnostic sensitivities and specificities of WITNESS FeLV-FIV (Zoetis and SNAP FIV/FeLV Combo Test (IDEXX for the detection of FeLV p27 antigen in the sera of experimentally feline leukemia virus (FeLV-infected cats. Methods Diagnostic sensitivities of WITNESS and SNAP were determined through testing of 47 serum samples collected from cats day 56 post-experimental infection with a virulent FeLV Rickard strain. Successful experimental infection was confirmed based on observation of FeLV antigen and proviral DNA in anti-coagulated (EDTA whole-blood samples by immunofluorescent antibody (IFA test and PCR, respectively. Diagnostic specificities of both tests were determined through testing of sera of 92 laboratory-housed, non-FeLV-exposed specific pathogen-free (SPF cats. Results Forty-one of 47 blood samples were IFA positive, whereas all 47 samples were PCR positive. All 92 non-FeLV-infected SPF cats were IFA and PCR negative. In comparison to IFA as the reference method, both WITNESS and SNAP tests yielded equivalent sensitivities and specificities of 100% and 97.8%, respectively. In comparison to PCR as the reference method, both WITNESS and SNAP tests likewise performed equivalently, with sensitivities and specificities of 91.5% and 100%, respectively. Conclusions and relevance Sensitivity and specificity of WITNESS FeLV-FIV for identifying FeLV p27 antigen in the sera of these experimentally FeLV-infected and non-FeLV-exposed SPF cats equaled those of the SNAP FIV/FeLV Combo Test. However, all positive results, regardless of the point-of-care test used, should be confirmed before making clinical decisions such as segregation from other cats or euthanasia.

  1. Hepatitis E virus antibody prevalence in wildlife in Poland.

    Science.gov (United States)

    Larska, M; Krzysiak, M K; Jabłoński, A; Kęsik, J; Bednarski, M; Rola, J

    2015-03-01

    Hepatitis E is an important public health problem mostly in developing but occasionally also in industrialized countries. Domestic and wildlife animals are considered reservoirs of the hepatitis E virus (HEV). Since no information on the prevalence of autochthonous HEV infections in human and animal in Poland is available, the aim of the study was to investigate the HEV seroprevalence of different wildlife species as potential virus reservoirs in the country. No HEV antibodies were found in any of the sera collected from the red deer (Cervus elaphus), European bison (Bison bonasus), roe deer (Capreolus capreolus), elk (Alces alces), fallow deer (Dama dama), sika deer (Cervus nippon), Tatra chamois (Rupicapra rupicapra tatrica) or brown bear (Ursus arctos). HEV-specific antibodies were detected in 44.4% (95% CI 38.3-50.7) serum samples originated only from wild boars. The percentage of seropositive wild boars differed significantly between the provinces and was positively correlated with the wild boar density and rurality of the area. This study showed that HEV circulates among wild boar population in Poland, and this species should be considered as an important reservoir of the virus. © 2014 Blackwell Verlag GmbH.

  2. Enhanced sensitivity in detection of antiviral antibody responses using biotinylation of foot-and-mouth disease virus (FMDV) capsids

    Science.gov (United States)

    Analysis of the immune response to infection of livestock by foot-and-mouth disease virus (FMDV) is most often reported as the serum antibody response to the virus. While measurement of neutralizing antibody has been sensitive and specific, measurements of the quality of the antibody response are le...

  3. Neutralising antibodies for Mayaro virus in Pantanal, Brazil

    Directory of Open Access Journals (Sweden)

    Alex Pauvolid-Corrêa

    2015-02-01

    Full Text Available The Pantanal hosts diverse wildlife species and therefore is a hotspot for arbovirus studies in South America. A serosurvey for Mayaro virus (MAYV, eastern (EEEV, western (WEEV and Venezuelan (VEEV equine encephalitis viruses was conducted with 237 sheep, 87 free-ranging caimans and 748 equids, including 37 collected from a ranch where a neurologic disorder outbreak had been recently reported. Sera were tested for specific viral antibodies using plaque-reduction neutralisation test. From a total of 748 equids, of which 264 were immunised with vaccine composed of EEEV and WEEV and 484 had no history of immunisation, 10 (1.3% were seropositive for MAYV and two (0.3% for VEEV using criteria of a ≥ 4-fold antibody titre difference. Among the 484 equids without history of immunisation, 48 (9.9% were seropositive for EEEV and four (0.8% for WEEV using the same criteria. Among the sheep, five were sero- positive for equine encephalitis alphaviruses, with one (0.4% for EEEV, one (0.4% for WEEV and three (1.3% for VEEV. Regarding free-ranging caimans, one (1.1% and three (3.4%, respectively, had low titres for neutralising antibodies to VEEV and undetermined alphaviruses. The neurological disorder outbreak could not be linked to the alphaviruses tested. Our findings represent strong evidence that MAYV and all equine encephalitis alphaviruses circulated in the Pantanal.

  4. Low intrathecal antibody production despite high seroprevalence of Epstein-Barr virus in multiple sclerosis: a review of the literature.

    Science.gov (United States)

    Ruprecht, Klemens; Wildemann, Brigitte; Jarius, Sven

    2018-02-01

    Patients with multiple sclerosis (MS) frequently have an intrathecal production of antibodies to different common viruses, which can be detected by elevated antiviral antibody indices (AIs). There is a strong and consistent association of MS and Epstein-Barr virus (EBV) infection. To systematically compare the frequencies of intrathecal antibody production to EBV, measles virus, rubella virus, varicella zoster virus (VZV) and herpes simplex virus (HSV) in patients with MS. Review of the English and German literature on the frequencies of intrathecal immunoglobulin (Ig)G antibody production, as defined by an elevated AI, to EBV, measles virus, rubella virus, VZV and HSV in adult and pediatric patients with MS. In nine original studies identified, the frequencies of an intrathecal production of antibodies to Epstein-Barr nuclear antigen-1 (33/340, 9.7%), EBV viral capsid antigen (12/279, 4.3%) and antigens from EBV-infected cell lines (14/90, 15.6%) in adult patients with MS were clearly lower (p ≤ 0.03 for all pairwise comparisons) than the frequencies of an intrathecal production of antibodies to measles virus (612/922, 66.4%), rubella virus (521/922, 56.5%), VZV (470/922, 51%; data from 17 original studies) and HSV (78/291, 26.8%; data from 6 original studies). Though based on a lower number of original studies and patients, findings in children with MS were essentially similar. As in adults and children with MS the seroprevalence of EBV is higher than the seroprevalences of the other investigated viruses, the lower frequency of elevated EBV AIs became even more pronounced after correction of the frequencies of elevated antiviral AIs for the seroprevalences of the respective viruses. Given the very high seroprevalence of EBV in MS, the frequency of intrathecally produced antibodies to EBV in patients with MS is paradoxically low compared to that of other common viruses. These findings are compatible with the recently proposed hypothesis that in individuals

  5. Broadly-Reactive Neutralizing and Non-neutralizing Antibodies Directed against the H7 Influenza Virus Hemagglutinin Reveal Divergent Mechanisms of Protection.

    Directory of Open Access Journals (Sweden)

    Gene S Tan

    2016-04-01

    Full Text Available In the early spring of 2013, Chinese health authorities reported several cases of H7N9 influenza virus infections in humans. Since then the virus has established itself at the human-animal interface in Eastern China and continues to cause several hundred infections annually. In order to characterize the antibody response to the H7N9 virus we generated several mouse monoclonal antibodies against the hemagglutinin of the A/Shanghai/1/13 (H7N9 virus. Of particular note are two monoclonal antibodies, 1B2 and 1H5, that show broad reactivity to divergent H7 hemagglutinins. Monoclonal antibody 1B2 binds to viruses of the Eurasian and North American H7 lineages and monoclonal antibody 1H5 reacts broadly to virus isolates of the Eurasian lineage. Interestingly, 1B2 shows broad hemagglutination inhibiting and neutralizing activity, while 1H5 fails to inhibit hemagglutination and demonstrates no neutralizing activity in vitro. However, both monoclonal antibodies were highly protective in an in vivo passive transfer challenge model in mice, even at low doses. Experiments using mutant antibodies that lack the ability for Fc/Fc-receptor and Fc/complement interactions suggest that the protection provided by mAb 1H5 is, at least in part, mediated by the Fc-fragment of the mAb. These findings highlight that a protective response to a pathogen may not only be due to neutralizing antibodies, but can also be the result of highly efficacious non-neutralizing antibodies not readily detected by classical in vitro neutralization or hemagglutination inhibition assays. This is of interest because H7 influenza virus vaccines induce only low hemagglutination inhibiting antibody titers while eliciting robust antibody titers as measured by ELISA. Our data suggest that these binding but non-neutralizing antibodies contribute to protection in vivo.

  6. Spread of human T-cell leukemia virus (HTLV-I) in the Dutch homosexual community

    NARCIS (Netherlands)

    Goudsmit, J.; de Wolf, F.; van de Wiel, B.; Smit, L.; Bakker, M.; Albrecht-van Lent, N.; Coutinho, R. A.

    1987-01-01

    Sequential sera of 697 homosexual men, participating in a prospective study (1984-1986) of the risk to acquire human immunodeficiency virus (HIV) or AIDS, were tested for antibodies to human T-cell leukaemia virus (HTLV-I) by particle agglutination and immunoblotting. No intravenous drug users were

  7. Cooperativity between CD8+ T cells, non-neutralizing antibodies, and alveolar macrophages is important for heterosubtypic influenza virus immunity.

    Directory of Open Access Journals (Sweden)

    Brian J Laidlaw

    2013-03-01

    Full Text Available Seasonal epidemics of influenza virus result in ∼36,000 deaths annually in the United States. Current vaccines against influenza virus elicit an antibody response specific for the envelope glycoproteins. However, high mutation rates result in the emergence of new viral serotypes, which elude neutralization by preexisting antibodies. T lymphocytes have been reported to be capable of mediating heterosubtypic protection through recognition of internal, more conserved, influenza virus proteins. Here, we demonstrate using a recombinant influenza virus expressing the LCMV GP33-41 epitope that influenza virus-specific CD8+ T cells and virus-specific non-neutralizing antibodies each are relatively ineffective at conferring heterosubtypic protective immunity alone. However, when combined virus-specific CD8 T cells and non-neutralizing antibodies cooperatively elicit robust protective immunity. This synergistic improvement in protective immunity is dependent, at least in part, on alveolar macrophages and/or other lung phagocytes. Overall, our studies suggest that an influenza vaccine capable of eliciting both CD8+ T cells and antibodies specific for highly conserved influenza proteins may be able to provide heterosubtypic protection in humans, and act as the basis for a potential "universal" vaccine.

  8. Prevalence of Hepatitis C virus antibody among undergraduates in ...

    African Journals Online (AJOL)

    Background: This study was conducted to determine the prevalence of hepatitis C virus antibody (anti-HCV), among a healthy university undergraduate population in south-western Nigeria. Materials and Methods: Relevant medical information of students who underwent the post-admission screening exercise for the year ...

  9. Cooperativity in virus neutralization by human monoclonal antibodies to two adjacent regions located at the amino terminus of hepatitis C virus E2 glycoprotein

    DEFF Research Database (Denmark)

    Keck, Zhenyong; Wang, Wenyan; Wang, Yong

    2013-01-01

    A challenge for hepatitis C virus (HCV) vaccine development is defining conserved epitopes that induce protective antibodies against this highly diverse virus. An envelope glycoprotein (E2) segment located at amino acids (aa) 412 to 423 contains highly conserved neutralizing epitopes. While...... at higher concentrations. However, the overall effect was additive neutralization. A similar pattern was observed when these antibodies were combined to block E2 binding to the HCV coreceptor, CD81. These findings demonstrate that both of these E2 regions participate in epitopes mediating virus...... (HCVcc) with various activities. Although nonneutralizing HC33 HMAbs were isolated, they had lower binding affinities than neutralizing HC33 HMAbs. These antibodies could be converted to neutralizing antibodies by affinity maturation. Unidirectional competition for binding to E2 was observed between HC33...

  10. Early low-titer neutralizing antibodies impede HIV-1 replication and select for virus escape.

    Directory of Open Access Journals (Sweden)

    Katharine J Bar

    Full Text Available Single genome sequencing of early HIV-1 genomes provides a sensitive, dynamic assessment of virus evolution and insight into the earliest anti-viral immune responses in vivo. By using this approach, together with deep sequencing, site-directed mutagenesis, antibody adsorptions and virus-entry assays, we found evidence in three subjects of neutralizing antibody (Nab responses as early as 2 weeks post-seroconversion, with Nab titers as low as 1∶20 to 1∶50 (IC(50 selecting for virus escape. In each of the subjects, Nabs targeted different regions of the HIV-1 envelope (Env in a strain-specific, conformationally sensitive manner. In subject CH40, virus escape was first mediated by mutations in the V1 region of the Env, followed by V3. HIV-1 specific monoclonal antibodies from this subject mapped to an immunodominant region at the base of V3 and exhibited neutralizing patterns indistinguishable from polyclonal antibody responses, indicating V1-V3 interactions within the Env trimer. In subject CH77, escape mutations mapped to the V2 region of Env, several of which selected for alterations of glycosylation. And in subject CH58, escape mutations mapped to the Env outer domain. In all three subjects, initial Nab recognition was followed by sequential rounds of virus escape and Nab elicitation, with Nab escape variants exhibiting variable costs to replication fitness. Although delayed in comparison with autologous CD8 T-cell responses, our findings show that Nabs appear earlier in HIV-1 infection than previously recognized, target diverse sites on HIV-1 Env, and impede virus replication at surprisingly low titers. The unexpected in vivo sensitivity of early transmitted/founder virus to Nabs raises the possibility that similarly low concentrations of vaccine-induced Nabs could impair virus acquisition in natural HIV-1 transmission, where the risk of infection is low and the number of viruses responsible for transmission and productive clinical

  11. Effect of low dose gamma-radiation upon Newcastle disease virus antibody level in chicken

    International Nuclear Information System (INIS)

    Vilic, M.; Gottstein, Z.; Ciglar Grozdanic, I.; Matanovic, K.; Miljanic, S.; Mazija, H.; Kraljevic, P.

    2009-01-01

    The specific antibody response against Newcastle disease virus in the blood serum of chickens hatched from eggs exposed to low dose gamma-radiation was studied. Materials and methods: Two groups of eggs of commercial meat chicken lines were irradiated with the dose of 0.30 Gy 60 Co gamma-rays before incubation and on the 19 th day of incubation, respectively. The same number of eggs unexposed to gamma-radiation served as controls. After hatching the group of chicken hatched from eggs irradiated on the 19 th day of incubation was not vaccinated while the group of chicken hatched from eggs irradiated before incubation was vaccinated on the 14 day. Specific serum anti-Newcastle disease virus antibodies were quantified by the hemagglutination inhibition assay with 4 HA units of Newcastle disease virus La Sota strain. Result: Specific antibody titres against Newcastle disease virus in the blood serum of chickens hatched from eggs irradiated before incubation and vaccinated on the 14 th day significantly increased on the 28 th day. Specific antibody titre against Newcastle disease virus in the blood serum of chickens hatched from eggs irradiated on the 19 th day of incubation and non-vaccinated was significantly higher on the 1 st and 14 th day. Conclusion: Acute irradiation of heavy breeding chicken eggs with the dose of 0.30 Gy 60 Co gamma-rays before incubation and on the 19 th day of incubation could have a stimulative effect on humoral immunity in chickens.

  12. Seroprevalence of Hepatitis A Virus Antibodies among the Patients with Chronic Hepatitis B in Turkey.

    Science.gov (United States)

    Tulek, Necla; Ozsoy, Metin; Moroglu, Cigdem; Cagla Sonmezer, Meliha; Temocin, Fatih; Tuncer Ertem, Gunay; Sebnem Erdinc, Fatma

    2015-01-01

    Hepatitis A virus (HAV) can cause significant pathology in patients with chronic hepatitis B virus (HBV), however, HAV can be prevented by vaccination. The aim of this study was to determine the implication of vaccination against HAV vaccine in patients with chronic hepatitis B. The seroprevalence of anti-HAV IgG antibodies was investigated in the patients with chronic hepatitis B. Anti-HAV IgG antibodies were detected by commercially available ELISA kit. A total of 673 patients (354 males, 319 females with age range of 17-78 years) with chronic hepatitis B were included the study. Hepatitis A virus seropositivity rate was 34% in the patients younger than 20 years, 79% in the age group of 20 to 29 years, and 100% after 35 years of age. Hepatitis A virus vaccination may be recommended for young adult patients with chronic hepatitis B in Turkey. Tulek N, Ozsoy M, Moroglu C, Sonmezer MC, Temocin F, Ertem GT, Erdinc FS. Seroprevalence of Hepatitis A Virus Antibodies among the Patients with Chronic Hepatitis B in Turkey. Euroasian J Hepato-Gastroenterol 2015;5(2):95-97.

  13. Report on Influenza A and B Viruses: Their Coinfection in a Saudi Leukemia Patient

    Directory of Open Access Journals (Sweden)

    Fahad N. Almajhdi

    2013-01-01

    Full Text Available Purpose. Influenza A and B viruses are the leading cause of respiratory infections in children worldwide, particularly in developing countries. There is a lack of data on coinfection of influenza A and B viruses circulating in Saudi Arabia. In this study, we aimed to identify the circulation of influenza viruses that contribute to respiratory tract infections in Saudi children. Methods. We collected 80 nasopharyngeal aspirates (NPAs from hospitalized children with acute respiratory illness (ARI at Riyadh during the period extended from October 2010 till April 2011. Samples were tested for the common respiratory viruses including influenza viruses by RT-PCR. Results. Overall, 6 samples were found positive for influenza A and/or B viruses. Among these positive clinical samples, only one collected sample from a female one-year-old immunocompromised child with leukemia showed a coinfection with influenza A and B viruses. In present study coinfection was confirmed by inoculation of the clinical specimen in specific pathogenfree embryonating chicken eggs and identification of the virus isolates by hemagglutination and one-step RT-PCR. Conclusion. This study opens the scene for studying the role of influenza virus’s coinfection in disease severity and virus evolution. Further studies are required to better understand the clinical importance of viral coinfection.

  14. Development, characterization and application of monoclonal antibodies against Brazilian Dengue virus isolates.

    Directory of Open Access Journals (Sweden)

    Camila Zanluca

    Full Text Available Dengue is the most prevalent human arboviral disease. The morbidity related to dengue infection supports the need for an early, quick and effective diagnostic test. Brazil is a hotspot for dengue, but no serological diagnostic test has been produced using Brazilian dengue virus isolates. This study aims to improve the development of immunodiagnostic methods for dengue virus (DENV detection through the production and characterization of 22 monoclonal antibodies (mAbs against Brazilian isolates of DENV-1, -2 and -3. The mAbs include IgG2bκ, IgG2aκ and IgG1κ isotypes, and most were raised against the envelope or the pre-membrane proteins of DENV. When the antibodies were tested against the four DENV serotypes, different reactivity patterns were identified: group-specific, subcomplex specific (DENV-1, -3 and -4 and DENV-2 and -3 and dengue serotype-specific (DENV-2 or -3. Additionally, some mAbs cross-reacted with yellow fever virus (YFV, West Nile virus (WNV and Saint Louis encephalitis virus (SLEV. None of the mAbs recognized the alphavirus Venezuelan equine encephalitis virus (VEEV. Furthermore, mAbs D3 424/8G, D1 606/A12/B9 and D1 695/12C/2H were used to develop a capture enzyme-linked immunosorbent assay (ELISA for anti-dengue IgM detection in sera from patients with acute dengue. To our knowledge, these are the first monoclonal antibodies raised against Brazilian DENV isolates, and they may be of special interest in the development of diagnostic assays, as well as for basic research.

  15. Structure of an antibody in complex with its mucin domain linear epitope that is protective against Ebola virus.

    Science.gov (United States)

    Olal, Daniel; Kuehne, Ana I; Bale, Shridhar; Halfmann, Peter; Hashiguchi, Takao; Fusco, Marnie L; Lee, Jeffrey E; King, Liam B; Kawaoka, Yoshihiro; Dye, John M; Saphire, Erica Ollmann

    2012-03-01

    Antibody 14G7 is protective against lethal Ebola virus challenge and recognizes a distinct linear epitope in the prominent mucin-like domain of the Ebola virus glycoprotein GP. The structure of 14G7 in complex with its linear peptide epitope has now been determined to 2.8 Å. The structure shows that this GP sequence forms a tandem β-hairpin structure that binds deeply into a cleft in the antibody-combining site. A key threonine at the apex of one turn is critical for antibody interaction and is conserved among all Ebola viruses. This work provides further insight into the mechanism of protection by antibodies that target the protruding, highly accessible mucin-like domain of Ebola virus and the structural framework for understanding and characterizing candidate immunotherapeutics.

  16. Respiratory syncytial virus neutralizing antibodies in cord blood, respiratory syncytial virus hospitalization, and recurrent wheeze

    DEFF Research Database (Denmark)

    Stensballe, Lone Graff; Ravn, Henrik; Kristensen, Kim

    2008-01-01

    BACKGROUND: Respiratory syncytial virus (RSV) hospitalization is associated with wheeze. OBJECTIVE: To examine the influence of maternally derived RSV neutralizing antibodies in cord blood on RSV hospitalization and recurrent wheeze in infancy. METHODS: Among children from the Danish National Birth...

  17. Mutations of the kissing-loop dimerization sequence influence the site specificity of murine leukemia virus recombination in vivo

    DEFF Research Database (Denmark)

    Mikkelsen, J G; Lund, Anders Henrik; Duch, M

    2000-01-01

    synthesis in newly infected cells. We have previously shown that template shifts within the 5' leader of murine leukemia viruses occur preferentially within the kissing stem-loop motif, a cis element crucial for in vitro RNA dimer formation. By use of a forced recombination approach based on single......-cycle transfer of Akv murine leukemia virus-based vectors harboring defective primer binding site sequences, we now report that modifications of the kissing-loop structure, ranging from a deletion of the entire sequence to introduction of a single point mutation in the loop motif, significantly disturb site...... specificity of recombination within the highly structured 5' leader region. In addition, we find that an intact kissing-loop sequence favors optimal RNA encapsidation and vector transduction. Our data are consistent with the kissing-loop dimerization model and suggest that a direct intermolecular RNA...

  18. Ocaratuzumab, an Fc-engineered antibody demonstrates enhanced antibody-dependent cell-mediated cytotoxicity in chronic lymphocytic leukemia.

    Science.gov (United States)

    Cheney, Carolyn M; Stephens, Deborah M; Mo, Xiaokui; Rafiq, Sarwish; Butchar, Jonathan; Flynn, Joseph M; Jones, Jeffrey A; Maddocks, Kami; O'Reilly, Adrienne; Ramachandran, Abhijit; Tridandapani, Susheela; Muthusamy, Natarajan; Byrd, John C

    2014-01-01

    Chronic lymphocytic leukemia (CLL) is common in both developed and developing nations where the need for inexpensive and convenient administration of therapy is apparent. Ocaratuzumab is a novel Fc-engineered humanized IgG1 anti-CD20 monoclonal antibody (mAb) designed for effective antibody-dependent cell-mediated cytotoxicity (ADCC) at very low concentrations that may facilitate sub-cutaneous (vs. intravenous) dosing. Here, we report ocaratuzumab's potency against CLL cells. In vitro assessment of ocaratuzumab's direct cytotoxicity (DC), complement-dependent cytotoxicity (CDC), antibody-dependent cellular phagocytosis (ADCP), and ADCC was performed on CLL cells. Ocaratuzumab induced DC, CDC, and ADCP similarly to rituximab or ofatumumab (anti-CD20 mAbs). However, ocaratuzumab showed an advantage in NK cell-mediated ADCC over these antibodies. In allogeneic ADCC, [E:T (effector:target) ratios = 25:1, 12:1, 6:1], ocaratuzumab (10 µg/mL) improved ADCC by ~3-fold compared with rituximab or ofatumumab (P<0.001 all tested E:T ratios). Notably, the superiority of ocaratuzumab-induced ADCC was observed at low concentrations (0.1-10 ug/ml; P<0.03; allogeneic assays). In extended allogeneic ADCC E:T titration, ocaratuzumab (0.1 µg/mL) demonstrated 19.4% more cytotoxicity than rituximab (E:T = 0.38:1; P = 0.0066) and 21.5% more cytotoxicity than ofatumumab (E:T = 1.5:1; P = 0.0015). In autologous ADCC, ocaratuzumab (10 µg/mL) demonstrated ~1.5-fold increase in cytotoxicity compared with rituximab or ofatumumab at all E:T ratios tested (E:Ts = 25:1,12:1,6:1; all P<0.001). Obinutuzumab, a glyco-engineered anti-CD20 mAb, showed no improvement in ADCC activity compared with ocaratuzumab. The enhanced ADCC of ocaratuzumab suggests that it may be effective at low concentrations. If supported by clinical investigation, this feature could potentially allow for subcutaneous dosing at low doses that could expand the potential of administering chemoimmunotherapy in developing

  19. Seroprevalence of Anti-Dengue Virus 2 Serocomplex antibodies in ...

    African Journals Online (AJOL)

    Introduction: There has been a recent increase in the spread of dengue to rural areas. Rural parts of western kenya are naturally prone to mosquito-borne diseases, however, limited research has been documented on infections with dengue. This study therefore investigated the presence of antibodies against dengue virus ...

  20. Removal of xenotropic murine leukemia virus by nanocellulose based filter paper.

    Science.gov (United States)

    Asper, M; Hanrieder, T; Quellmalz, A; Mihranyan, A

    2015-11-01

    The removal of xenotrpic murine leukemia virus (xMuLV) by size-exclusion filter paper composed of 100% naturally derived cellulose was validated. The filter paper was produced using cellulose nanofibers derived from Cladophora sp. algae. The filter paper was characterized using atomic force microscopy, scanning electron microscopy, helium pycnometry, and model tracer (100 nm latex beads and 50 nm gold nanoparticles) retention tests. Following the filtration of xMuLV spiked solutions, LRV ≥5.25 log10 TCID50 was observed, as limited by the virus titre in the feed solution and sensitivity of the tissue infectivity test. The results of the validation study suggest that the nanocellulose filter paper is useful for removal of endogenous rodent retroviruses and retrovirus-like particles during the production of recombinant proteins. Copyright © 2015 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  1. Persistence of Antibodies to West Nile Virus in Naturally Infected Rock Pigeons (Columba livia)

    Science.gov (United States)

    Gibbs, Samantha E. J.; Hoffman, Douglas M.; Stark, Lillian M.; Marlenee, Nicole L.; Blitvich, Bradley J.; Beaty, Barry J.; Stallknecht, David E.

    2005-01-01

    Wild caught rock pigeons (Columba livia) with antibodies to West Nile virus were monitored for 15 months to determine antibody persistence and compare results of three serologic techniques. Antibodies persisted for the entire study as detected by epitope-blocking enzyme-linked immunosorbent assay and plaque reduction neutralization test. Maternal antibodies in squabs derived from seropositive birds persisted for an average of 27 days. PMID:15879030

  2. Antibody Prophylaxis Against Dengue Virus 2 Infection in Non-Human Primates.

    Science.gov (United States)

    Simmons, Monika; Putnak, Robert; Sun, Peifang; Burgess, Timothy; Marasco, Wayne A

    2016-11-02

    Passive immunization with anti-dengue virus (DENV) immune serum globulin (ISG) or monoclonal antibodies (Mabs) may serve to supplement or replace vaccination for short-term dengue immune prophylaxis. In the present study, we sought to establish proof-of-concept by evaluating several DENV-neutralizing antibodies for their ability to protect rhesus macaques against viremia following live virus challenge, including human anti-dengue ISG, and a human Mab (Mab11/wt) and its genetically engineered variant (Mab11/mutFc) that is unable to bind to cells with Fc gamma receptors (FcγR) and potentiate antibody-dependent enhancement (ADE). In the first experiment, groups of animals received ISG or Mab11/wt at low doses (3-10 mg/kg) or a saline control followed by challenge with DENV-2 at day 10 or 30. After passive immunization, only low-titered circulating virus-neutralizing antibody titers were measured in both groups, which were undetectable by day 30. After challenge at day 10, a reduction in viremia duration compared with the control was seen only in the ISG group (75%). However, after a day 30 challenge, no reduction in viremia was observed in both immunized groups. In a second experiment to test the effect of higher antibody doses on short-term protection, groups received either ISG, Mab11/wt, Mab11/mutFc (each at 25 mg/kg) or saline followed by challenge with DENV-2 on day 10. Increased virus-neutralizing antibody titers were detected in all groups at day 5 postinjection, with geometric mean titers (GMTs) of 464 (ISG), 313 (Mab11/wt), and 309 (Mab11/mutFc). After challenge, there was complete protection against viremia in the group that received ISG, and a reduction in viremia duration of 89% and 83% in groups that received Mab11/wt and Mab11/mutFc, respectively. An in vitro ADE assay in Fcγ receptor-bearing K562 cells with sera collected immediately before challenge showed increased DENV-2 infection levels in the presence of both ISG and Mab11/wt, which peaked at a

  3. A humanised murine monoclonal antibody protects mice from Venezuelan equine encephalitis virus, Everglades virus and Mucambo virus when administered up to 48 h after airborne challenge

    Energy Technology Data Exchange (ETDEWEB)

    O' Brien, Lyn M., E-mail: lmobrien@dstl.gov.uk; Goodchild, Sarah A.; Phillpotts, Robert J.; Perkins, Stuart D.

    2012-05-10

    Currently there are no licensed antiviral treatments for the Alphaviruses Venezuelan equine encephalitis virus (VEEV), Everglades virus and Mucambo virus. We previously developed a humanised version of the mouse monoclonal antibody 1A3B-7 (Hu1A3B-7) which exhibited a wide range of reactivity in vitro and was able to protect mice from infection with VEEV. Continued work with the humanised antibody has now demonstrated that it has the potential to be a new human therapeutic. Hu1A3B-7 successfully protected mice from infection with multiple Alphaviruses. The effectiveness of the humanisation process was determined by assessing proliferation responses in human T-cells to peptides derived from the murine and humanised versions of the V{sub H} and V{sub L} domains. This analysis showed that the number of human T-cell epitopes within the humanised antibody had been substantially reduced, indicating that Hu1A3B-7 may have reduced immunogenicity in vivo.

  4. A humanised murine monoclonal antibody protects mice from Venezuelan equine encephalitis virus, Everglades virus and Mucambo virus when administered up to 48 h after airborne challenge

    International Nuclear Information System (INIS)

    O'Brien, Lyn M.; Goodchild, Sarah A.; Phillpotts, Robert J.; Perkins, Stuart D.

    2012-01-01

    Currently there are no licensed antiviral treatments for the Alphaviruses Venezuelan equine encephalitis virus (VEEV), Everglades virus and Mucambo virus. We previously developed a humanised version of the mouse monoclonal antibody 1A3B-7 (Hu1A3B-7) which exhibited a wide range of reactivity in vitro and was able to protect mice from infection with VEEV. Continued work with the humanised antibody has now demonstrated that it has the potential to be a new human therapeutic. Hu1A3B-7 successfully protected mice from infection with multiple Alphaviruses. The effectiveness of the humanisation process was determined by assessing proliferation responses in human T-cells to peptides derived from the murine and humanised versions of the V H and V L domains. This analysis showed that the number of human T-cell epitopes within the humanised antibody had been substantially reduced, indicating that Hu1A3B-7 may have reduced immunogenicity in vivo.

  5. Laboratory and wild-derived mice with multiple loci for production of xenotropic murine leukemia virus.

    Science.gov (United States)

    Kozak, C A; Hartley, J W; Morse, H C

    1984-07-01

    Mendelian segregation analysis was used to define genetic loci for the induction of infectious xenotropic murine leukemia virus in several laboratory and wild-derived mice. MA/My mice contain two loci for xenotropic virus inducibility, one of which, Bxv -1, is the only induction locus carried by five other inbred strains. The second, novel MA/My locus, designated Mxv -1, is unlinked to Bxv -1 and shows a lower efficiency of virus induction. The NZB mouse carries two induction loci; both are distinct from Bxv -1 since neither is linked to the Pep-3 locus on chromosome 1. Finally, one partially inbred strain derived from the wild Japanese mouse, Mus musculus molossinus, carries multiple (at least three) unlinked loci for induction of xenotropic virus. Although it is probable that inbred strains inherited xenotropic virus inducibility from Japanese mice, our data suggest that none of the induction loci carried by this particular M. m. molossinus strain are allelic with Bxv -1.

  6. A novel, colorimetric neutralization assay for measuring antibodies to influenza viruses.

    Science.gov (United States)

    Lehtoranta, Liisa; Villberg, Anja; Santanen, Riitta; Ziegler, Thedi

    2009-08-01

    A colorimetric cell proliferation assay for measuring neutralizing antibodies to influenza viruses in human sera is described. Following a 90-min incubation, the serum-virus mixture was transferred to Madin-Darby canine kidney cells cultured in 96-well plates. After further incubation for three days, a tetrazolium salt was added to the wells. Cellular mitochondrial dehydrogenases cleave the tetrazolium salt to formazan, and the resulting color change is read by a spectrophotometer. The absorbance values correlate directly to the number of viable cells in the assay well and thus also to the neutralizing activity of influenza-specific antibodies present in the serum. With the few hands-on manipulations required, this assay allows simultaneous testing of a considerable number of sera, offers opportunities for automation, and is suitable for use under biosafety level-3 conditions. The test was used to study the antibody response after the administration of seasonal, inactivated, trivalent influenza vaccine. Antibody titers determined by the neutralization test in pre- and post-vaccination serum pairs were compared with those obtained by the hemagglutination inhibition assay. The neutralization test yielded higher pre- and post-vaccination titers and a larger number of significant increases in post-vaccination antibody titer than the hemagglutination inhibition test. This new test format could serve as a valuable laboratory tool for influenza vaccine studies.

  7. Intramuscular Adeno-Associated Virus-Mediated Expression of Monoclonal Antibodies Provides 100% Protection Against Ebola Virus Infection in Mice.

    Science.gov (United States)

    van Lieshout, Laura P; Soule, Geoff; Sorensen, Debra; Frost, Kathy L; He, Shihua; Tierney, Kevin; Safronetz, David; Booth, Stephanie A; Kobinger, Gary P; Qiu, Xiangguo; Wootton, Sarah K

    2018-03-05

    The 2013-2016 West Africa outbreak demonstrated the epidemic potential of Ebola virus and highlighted the need for counter strategies. Monoclonal antibody (mAb)-based therapies hold promise as treatment options for Ebola virus infections. However, production of clinical-grade mAbs is labor intensive, and immunity is short lived. Conversely, adeno-associated virus (AAV)-mediated mAb gene transfer provides the host with a genetic blueprint to manufacture mAbs in vivo, leading to steady release of antibody over many months. Here we demonstrate that AAV-mediated expression of nonneutralizing mAb 5D2 or 7C9 confers 100% protection against mouse-adapted Ebola virus infection, while neutralizing mAb 2G4 was 83% protective. A 2-component cocktail, AAV-2G4/AAV-5D2, provided complete protection when administered 7 days prior to challenge and was partially protective with a 3-day lead time. Finally, AAV-mAb therapies provided sustained protection from challenge 5 months following AAV administration. AAV-mAb may be a viable alternative strategy for vaccination against emerging infectious diseases.

  8. Cell division requirement for activation of murine leukemia virus in cell culture by irradiation

    International Nuclear Information System (INIS)

    Otten, J.A.; Quarles, J.M.; Tennant, R.W.

    1976-01-01

    Actively dividing cultures of AKR mouse cells were exposed to relatively low dose-rates of γ radiation and tested for activation of endogenous leukemia viruses. Efficient and reproducible induction of virus was obtained with actively dividing cells, but cultures deprived of serum to inhibit cell division before and during γ irradiation were not activated, even when medium with serum was added immediately after irradiation. These results show that cell division was required for virus induction but that a stable intermediate similar to the state induced by halogenated pyrimidines was not formed. In actively dividing AKR cell cultures, virus activation appeared to be proportional to the dose of γ radiation; the estimated frequency of activation was 1-8 x 10 - 5 per exposed cell and the efficiency of activation was approximately 0.012 inductions per cell per rad. Other normal primary and established mouse cell cultures tested were not activated by γ radiation. The requirement of cell division for radiation and chemical activation may reflect some common mechanism for initiation of virus expression

  9. Erythema multiforme in a patient with recurrent non-hodgkins lymphoma/chronic lymphocytic leukemia

    Directory of Open Access Journals (Sweden)

    Siva Kumara Shankari

    2012-01-01

    Full Text Available Erythema multiforme major (EMM is a hypersensitivity reaction usually secondary to medications, viruses or other infections. Its presentation is fairly typical with a symmetrical distribution of vesicles, bullae or targeted lesions on the upper body, arms, legs, palms, feet and oral mucosa. The authors present a delineated case of EMM in association with chronic lymphocytic leukemia (CLL and non-Hodgkin′s lymphoma (NHL with a very unusual clinical presentation evolving overtime into a unique, almost dermatomal distribution. Typical therapies were not initially helpful and intravenous immunoglobulin antibody had to be administered.

  10. Diagnostic potential of recombinant scFv antibodies generated against hemagglutinin protein of influenza A virus

    Directory of Open Access Journals (Sweden)

    Roopali eRajput

    2015-09-01

    Full Text Available Human influenza A viruses have been the cause of enormous socio-economic losses worldwide. In order to combat such a notorious pathogen, hemagglutinin protein (HA has been a preferred target for generation of neutralizing-antibodies, as potent therapeutic/ diagnostic agents. In the present study, recombinant anti-HA single chain variable fragment (scFv antibodies were constructed using the phage display technology to aid in diagnosis and treatment of human influenza A virus infections. Spleen cells of mice hyper-immunized with A/New Caledonia/20/99 (H1N1 virus were used as the source for recombinant antibody (rAb production. The antigen-binding phages were quantified after 6 rounds of bio-panning against A/New Caledonia/20/99 (H1N1, A/California/07/2009 (H1N1-like, or A/Udorn/307/72(H3N2 viruses. The phage yield was maximum for the A/New Caledonia/20/99 (H1N1, however, considerable cross-reactivity was observed for the other virus strains as well. The HA-specific polyclonal rAb preparation was subjected to selection of single clones for identification of high reactive relatively conserved epitopes. The high affinity rAbs were tested against certain known conserved HA epitopes by peptide ELISA. Three recombinant mAbs showed reactivity with both the H1N1 strains and one (C5 showed binding with all the three viral strains. The C5 antibody was thus used for development of an ELISA test for diagnosis of influenza virus infection. Based on the sample size in the current analysis, the ELISA test demonstrated 83.9% sensitivity and 100% specificity. Thus, the ELISA, developed in our study, may prove as a cheaper alternative to the presently used real time RT-PCR test for detection of human influenza A viruses in clinical specimens, which will be beneficial, especially in the developing countries. Since, the two antibodies identified in this study are reactive to conserved HA epitopes; these may prove as potential therapeutic agents as well.

  11. Seroprevalence of Hepatitis C Virus (HCV) antibodies in pregnant ...

    African Journals Online (AJOL)

    Background: Hepatitis C virus (HCV) infection is a major public health concern. The aim of this study was to ascertain the seroprevalence and risk factors of HCV antibodies among pregnant women in Anyigba, Kogi State North Central Nigeria. Materials and methods:Blood samples (5mls) were collected from one hundred ...

  12. Screening response to hepatitis c virus antibodies among diabetic ...

    African Journals Online (AJOL)

    Epidemiological studies have suggested that hepatitis C virus (HCV) infection is a risk factor for the development of diabetes mellitus (DM) type 2; hence, this study was carried out to investigate the prevalence of HCV antibodies among diabetic patients attending the University of Ilorin Teaching Hospital (UITH), Ilorin, north ...

  13. The production of antibody by invading B cells is required for the clearance of rabies virus from the central nervous system.

    Directory of Open Access Journals (Sweden)

    D Craig Hooper

    2009-10-01

    Full Text Available The pathogenesis of rabies is associated with the inability to deliver immune effectors across the blood-brain barrier and to clear virulent rabies virus from CNS tissues. However, the mechanisms that facilitate immune effector entry into CNS tissues are induced by infection with attenuated rabies virus.Infection of normal mice with attenuated rabies virus but not immunization with killed virus can promote the clearance of pathogenic rabies virus from the CNS. T cell activity in B cell-deficient mice can control the replication of attenuated virus in the CNS, but viral mRNA persists. Low levels of passively administered rabies virus-neutralizing antibody reach infected cells in the cerebellum of B cell-deficient mice but are not sufficient to mediate virus clearance. Production of rabies virus-specific antibody by B cells invading CNS tissues is required for this process, and a substantial proportion of the B cells that accumulate in the CNS of mice infected with attenuated rabies virus produce virus-specific antibodies.The mechanisms required for immune effectors to enter rabies virus-infected tissues are induced by infection with attenuated rabies virus but not by infection with pathogenic rabies viruses or immunization with killed virus. T cell activities can inhibit rabies virus replication, but the production of rabies virus-specific antibodies by infiltrating B cells, as opposed to the leakage of circulating antibody across the BBB, is critical to elimination of the virus. These findings suggest that a pathogenic rabies virus infection may be treatable after the virus has reached the CNS tissues, providing that the appropriate immune effectors can be targeted to the infected tissues.

  14. Canine distemper virus DNA vaccination of mink can overcome interference by maternal antibodies

    DEFF Research Database (Denmark)

    Jensen, Trine Hammer; Nielsen, Line; Aasted, Bent

    2015-01-01

    Canine distemper virus (CDV) is highly contagious and can cause severe disease against which conventional live vaccines are ineffective in the presence of maternal antibodies. Vaccination in the presences of maternal antibodies was challenged by vaccination of 5 days old and 3 weeks old mink kits...

  15. Detection of canine distemper virus serum neutralizing antibodies in captive U.S. phocids.

    Science.gov (United States)

    Clancy, Meredith M; Gamble, Kathryn C; Travis, Dominic A

    2013-03-01

    Antibodies to morbilliviruses have been documented in free-ranging pinnipeds throughout populations in the Atlantic and Arctic Oceans, but not from the Pacific Ocean. As a symbolic geographic barrier between the exposed Atlantic and naive Pacific populations, the captive phocid population in North America had undocumented serologic status. In this study, canine distemper virus (CDV) serum neutralization assays were used to assess the prevalence of antibodies in this population with participation of 25 U.S. institutions from grey seals (Halichoerus grypus, n = 6) and harbor seals (Phoca vitulina, n = 108). Historic and environmental risk factors associated with the epidemiology of distemper virus were collected by survey. Based on antibodies to canine distemper virus, the prevalence of exposure in this population was 25.5%, with 28 seals (grey, n = 2; harbor, n = 26) demonstrating antibody titers > or = 1:16, and positive titers ranged from 1:4 to 1:1,536. By survey analysis, strong associations with seropositive status were identified for captive origin (P = 0.013) and movement among institutions (P = 0.024). Size of population has positive correlation with likelihood of seropositive seals at an institution (P = 0.020). However, no major husbandry or enclosure-based risk factors were identified in institutions with seropositive seals, and no interaction between individual or institutional risk factors was identified. Previously undocumented prior to this study, CDV antibodies were measured in harbor seals (n = 2) recently stranded from the Pacific coast.

  16. Detection of cytokine expression patterns in the peripheral blood of patients with acute leukemia by antibody microarray analysis.

    Science.gov (United States)

    Li, Qing; Li, Mei; Wu, Yao-hui; Zhu, Xiao-jian; Zeng, Chen; Zou, Ping; Chen, Zhi-chao

    2014-04-01

    The cytokines of acute leukemia (AL) patients have certain expression patterns, forming a complex network involved in diagnosis, progression, and prognosis. We collected the serum of different AL patients before and after complete remission (CR) for detection of cytokines by using an antibody chip. The expression patterns of cytokines were determined by using bioinformatics computational analysis. The results showed that there were significant differences in the cytokine expression patterns between AL patients and normal controls, as well as between acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL). In confirmatory test, ELISA revealed the expression of uPAR in AL. Moreover, the bioinformatic analysis showed that the differentially expressed cytokines among the AL groups were involved in different biological behaviors and were closely related with the development of the disease. It was concluded that the cytokine expression pattern of AL patients is significantly different from that of healthy volunteers. Also, differences of cytokine expression patterns exist between AML and ALL, and between before and after CR in the same subtype of AL, which holds important clinical significance for revealing disease progression.

  17. A serological survey for avian infectious bronchitis virus and Newcastle disease virus antibodies in backyard (free-range) village chickens in Mexico.

    Science.gov (United States)

    Gutierrez-Ruiz, E J; Ramirez-Cruz, G T; Camara Gamboa, E I; Alexander, D J; Gough, R E

    2000-12-01

    The commercial flocks in Yucatan, Mexico are free of Newcastle disease virus (NDV) in its velogenic viscerotropic form, but little is known about the disease status of backyard poultry. A seroprevalence survey in 30 villages using haemagglutination inhibition (HI) tests for infectious bronchitis virus (IBV) and NDV antibodies was carried out from December 1997 to June 1998. The seroprevalences were 56.5% (95% CI 50-63%) for IBV and 2.2% (95% CI 0.5-3.8%) for NDV. All the villages had chickens that were positive for antibodies to IBV and nine of the villages had chickens that were positive for antibodies to NDV. This suggests that IBV may be responsible for a large proportion of the respiratory disease observed in backyard chickens in Yucatan. The implications of these findings are discussed, including the highly susceptible status of the backyard chickens in Yucatan to NDV and the possibility of this virus being one cause of the syndrome known as mortandad by the local people.

  18. Comparison of neutralizing and hemagglutination-inhibiting antibody responses to influenza A virus vaccination of human immunodeficiency virus-infected individuals

    NARCIS (Netherlands)

    Benne, CA; Harmsen, M; Tavares, L; Kraaijeveld, CA; De Jong, JC

    A neutralization enzyme immunoassay (N-EIA) was used to determine the neutralizing serum antibody titers to influenza A/Taiwan/1/86 (H1N1) and Beijing/353/89 (H3N2) viruses after vaccination of 51 human immunodeficiency virus (HIV) type 1-infected individuals and 10 healthy noninfected controls

  19. Antibodies to henipavirus or henipa-like viruses in domestic pigs in Ghana, West Africa.

    Directory of Open Access Journals (Sweden)

    David T S Hayman

    Full Text Available Henipaviruses, Hendra virus (HeV and Nipah virus (NiV, have Pteropid bats as their known natural reservoirs. Antibodies against henipaviruses have been found in Eidolon helvum, an old world fruit bat species, and henipavirus-like nucleic acid has been detected in faecal samples from E. helvum in Ghana. The initial outbreak of NiV in Malaysia led to over 265 human encephalitis cases, including 105 deaths, with infected pigs acting as amplifier hosts for NiV during the outbreak. We detected non-neutralizing antibodies against viruses of the genus Henipavirus in approximately 5% of pig sera (N = 97 tested in Ghana, but not in a small sample of other domestic species sampled under a E. helvum roost. Although we did not detect neutralizing antibody, our results suggest prior exposure of the Ghana pig population to henipavirus(es. Because a wide diversity of henipavirus-like nucleic acid sequences have been found in Ghanaian E. helvum, we hypothesise that these pigs might have been infected by henipavirus(es sufficiently divergent enough from HeVor NiV to produce cross-reactive, but not cross-neutralizing antibodies to HeV or NiV.

  20. Application of xenogeneic anti-canine distemper virus antibodies in treatment of canine distemper puppies.

    Science.gov (United States)

    Liu, P C; Chen, C A; Chen, C M; Yen, C H; Lee, M H; Chuang, C K; Tu, C F; Su, B L

    2016-11-01

    The clinical feasibility of passive immunotherapy has not been demonstrated in dogs naturally infected with canine distemper. In this study, porcine anti-canine distemper virus IgG and F(ab') 2 antibody fragments were used to treat infected puppies. A total of 41 naturally infected puppies (age Äsix months) exhibiting severe respiratory signs, but lacking neurological signs, were enrolled in the study. Twenty-five puppies were treated with a combination of IgG or F(ab') 2 antibody fragments (Group 1) and supportive therapy and 16 puppies received routine supportive care only (Group 2). The survival rate of dogs in Group 1 (19/25; 76%) was significantly higher than that in Group 2 (5/16; 31·3%) (Pdistemper virus antibodies improved survival in puppies affected with canine distemper with minimal adverse effects. Therefore, this therapy could be considered for treatment of endangered animal species infected with canine distemper virus. © 2016 British Small Animal Veterinary Association.

  1. Measles Virus Neutralizing Antibodies in Intravenous Immunoglobulins: Is an Increase by Revaccination of Plasma Donors Possible?

    Science.gov (United States)

    Modrof, Jens; Tille, Björn; Farcet, Maria R; McVey, John; Schreiner, Jessica A; Borders, Charles M; Gudino, Maria; Fitzgerald, Peter; Simon, Toby L; Kreil, Thomas R

    2017-11-15

    We report a screen of plasma donors confirming that widespread use of childhood measles vaccination since 1963 resulted in a decrease in average measles virus antibody titers among plasma donors, which is reflected in intravenous immunoglobulins (IVIGs). The measles virus antibody titer, however, is a potency requirement for IVIGs, as defined in a Food and Drug Administration regulation. To mitigate the decline in measles virus antibody titers in IVIGs and to ensure consistent product release, revaccination of plasma donors was investigated as a means to boost titers. However, revaccination-induced titer increases were only about 2-fold and short-lived. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  2. Felix Hoppe-Seyler Lecture 1997. Protective antibody responses against viruses.

    Science.gov (United States)

    Zinkernagel, R M

    1997-08-01

    Neutralizing antibody responses against the acute cytopathic vesicular stomatitis virus (VSV) have been studied in mice to evaluate their general characteristics including specificity, self-/non-self discrimination and memory. IgM responses are generated very early, by day 3 to 4, in a T helper cell-independent fashion and without VSV having polyclonal activating capacities. The order of the glycoprotein tips on the virus envelope (multiple, 8-10 nm distance, paracrystalline) exhibiting the neutralizing determinants are key to this prompt response. These paracrystalline identical multimeric antigens are characteristic of infectious agents and are always reacted against by B cells. Self-antigens that are accessible to B cells in the intact host are either monomeric in serum or mobile multimers on cell surfaces; these configurations need contact dependent or contact independent T help, respectively. Because T help is tolerant against self-antigens, no anti-self B cell responses are usually induced against monomeric self-antigens. If collagen or DNA (rigid multimeric self-antigens) become accessible, however, they may become targets of auto-antibody responses. The antibody repertoire against VSV is partially contained in the germline and partially is generated by somatic mutation; they seem not to undergo affinity-maturation. In any case protection against lethal infection is dependent upon strictly T helper cell dependent IgG generated by day 6 to 7 and reaches a protective level of about 1-10 micrograms/ml. Interesting affinity/avidity and onrate above a minimal threshold are of no apparent advantage for protection in vivo. Maintenance of these antibody levels by antigen depots, and not the presence of memory B cells alone, is key to providing protective immunological memory. Collectively these data suggest that studying biologically important protective antibody responses may modify some of the parameters that have been defined by studying hapten specific antibody

  3. Bovine Leukemia Virus Infection in Dairy Cattle: Effect on Serological Response to Immunization against J5 Escherichia coli Bacterin

    Directory of Open Access Journals (Sweden)

    Ronald J. Erskine

    2011-01-01

    Full Text Available Thirteen bovine leukemia virus- (BLV- negative and 22 BLV-positive Holstein cows were immunized with J5 Escherichia coli bacterin at dry off, three weeks before calving, during the second week after calving, and three weeks after the third immunization. Serum was collected before the initial immunization, immediately before the third and fourth immunizations, and 21 days after the fourth immunization. Anti-J5 E. coli IgM, IgG1, and IgG2 titers were determined by ELISA. Anti-J5 E. coli IgM titers did not differ significantly (P=.98 between groups. Increases in anti-J5 E. coli IgG1 titers were higher in the BLV-negative cows (P=.057. Geometric mean anti-J5 E. coli IgG2 titers increased fourfold in the BLV-negative cows, which was significantly higher (P=.007 than the twofold increase in the BLV-positive cows. Cattle infected with BLV may have impaired serologic responses following immunization with J5 bacterin, and response may differ according to antibody isotype.

  4. Discovery of drugs that possess activity against feline leukemia virus.

    Science.gov (United States)

    Greggs, Willie M; Clouser, Christine L; Patterson, Steven E; Mansky, Louis M

    2012-04-01

    Feline leukemia virus (FeLV) is a gammaretrovirus that is a significant cause of neoplastic-related disorders affecting cats worldwide. Treatment options for FeLV are limited, associated with serious side effects, and can be cost-prohibitive. The development of drugs used to treat a related retrovirus, human immunodeficiency virus type 1 (HIV-1), has been rapid, leading to the approval of five drug classes. Although structural differences affect the susceptibility of gammaretroviruses to anti-HIV drugs, the similarities in mechanism of replication suggest that some anti-HIV-1 drugs may also inhibit FeLV. This study demonstrates the anti-FeLV activity of four drugs approved by the US FDA (Food and Drug Administration) at non-toxic concentrations. Of these, tenofovir and raltegravir are anti-HIV-1 drugs, while decitabine and gemcitabine are approved to treat myelodysplastic syndromes and pancreatic cancer, respectively, but also have anti-HIV-1 activity in cell culture. Our results indicate that these drugs may be useful for FeLV treatment and should be investigated for mechanism of action and suitability for veterinary use.

  5. A rapid and quantitative assay for measuring antibody-mediated neutralization of West Nile virus infection

    International Nuclear Information System (INIS)

    Pierson, Theodore C.; Sanchez, Melissa D.; Puffer, Bridget A.; Ahmed, Asim A.; Geiss, Brian J.; Valentine, Laura E.; Altamura, Louis A.; Diamond, Michael S.; Doms, Robert W.

    2006-01-01

    West Nile virus (WNV) is a neurotropic flavivirus within the Japanese encephalitis antigenic complex that is responsible for causing West Nile encephalitis in humans. The surface of WNV virions is covered by a highly ordered icosahedral array of envelope proteins that is responsible for mediating attachment and fusion with target cells. These envelope proteins are also primary targets for the generation of neutralizing antibodies in vivo. In this study, we describe a novel approach for measuring antibody-mediated neutralization of WNV infection using virus-like particles that measure infection as a function of reporter gene expression. These reporter virus particles (RVPs) are produced by complementation of a sub-genomic replicon with WNV structural proteins provided in trans using conventional DNA expression vectors. The precision and accuracy of this approach stem from an ability to measure the outcome of the interaction between antibody and viral antigens under conditions that satisfy the assumptions of the law of mass action as applied to virus neutralization. In addition to its quantitative strengths, this approach allows the production of WNV RVPs bearing the prM-E proteins of different WNV strains and mutants, offering considerable flexibility for the study of the humoral immune response to WNV in vitro. WNV RVPs are capable of only a single round of infection, can be used under BSL-2 conditions, and offer a rapid and quantitative approach for detecting virus entry and its inhibition by neutralizing antibody

  6. Adjuvant-Mediated Epitope Specificity and Enhanced Neutralizing Activity of Antibodies Targeting Dengue Virus Envelope Protein

    Directory of Open Access Journals (Sweden)

    Denicar Lina Nascimento Fabris Maeda

    2017-09-01

    Full Text Available The heat-labile toxins (LT produced by enterotoxigenic Escherichia coli display adjuvant effects to coadministered antigens, leading to enhanced production of serum antibodies. Despite extensive knowledge of the adjuvant properties of LT derivatives, including in vitro-generated non-toxic mutant forms, little is known about the capacity of these adjuvants to modulate the epitope specificity of antibodies directed against antigens. This study characterizes the role of LT and its non-toxic B subunit (LTB in the modulation of antibody responses to a coadministered antigen, the dengue virus (DENV envelope glycoprotein domain III (EDIII, which binds to surface receptors and mediates virus entry into host cells. In contrast to non-adjuvanted or alum-adjuvanted formulations, antibodies induced in mice immunized with LT or LTB showed enhanced virus-neutralization effects that were not ascribed to a subclass shift or antigen affinity. Nonetheless, immunosignature analyses revealed that purified LT-adjuvanted EDIII-specific antibodies display distinct epitope-binding patterns with regard to antibodies raised in mice immunized with EDIII or the alum-adjuvanted vaccine. Notably, the analyses led to the identification of a specific EDIII epitope located in the EF to FG loop, which is involved in the entry of DENV into eukaryotic cells. The present results demonstrate that LT and LTB modulate the epitope specificity of antibodies generated after immunization with coadministered antigens that, in the case of EDIII, was associated with the induction of neutralizing antibody responses. These results open perspectives for the more rational development of vaccines with enhanced protective effects against DENV infections.

  7. Potent neutralization of influenza A virus by a single-domain antibody blocking M2 ion channel protein.

    Directory of Open Access Journals (Sweden)

    Guowei Wei

    Full Text Available Influenza A virus poses serious health threat to humans. Neutralizing antibodies against the highly conserved M2 ion channel is thought to offer broad protection against influenza A viruses. Here, we screened synthetic Camel single-domain antibody (VHH libraries against native M2 ion channel protein. One of the isolated VHHs, M2-7A, specifically bound to M2-expressed cell membrane as well as influenza A virion, inhibited replication of both amantadine-sensitive and resistant influenza A viruses in vitro, and protected mice from a lethal influenza virus challenge. Moreover, M2-7A showed blocking activity for proton influx through M2 ion channel. These pieces of evidence collectively demonstrate for the first time that a neutralizing antibody against M2 with broad specificity is achievable, and M2-7A may have potential for cross protection against a number of variants and subtypes of influenza A viruses.

  8. Electron microscopic study of spontaneous and experimentally induced leukemia in IRC mice

    International Nuclear Information System (INIS)

    Hiraki, S.; Ranadive, K.J.; Dmochowski, L.

    1974-01-01

    Spontaneous, serially transplanted, and experimentally induced leukemias of ICRC mice were studied by electron microscopy in an attempt to detect the presence of virus particles, if any, and to observe the influence of chemical and hormonal treatment on the presence of these virus particles. The first series of experiments included spontaneous, serially transplanted, and radiation-induced leukemia. The paucity of type C virus particles was quite conspicuous in spontaneous leukemia. Serially transplanted and radiation-accelerated leukemic lesions showed the presence of some type C and intracisternal type A particles. Found in two of these leukemic lesions (thymus and lymphosarcoma), in addition to type C virus particles, were budding and some mature type B virus particles, and numerous intracytoplasmic type A particles. ''Viropexis'' of type B virus particles has been observed in the lymphosarcoma and in a leukemic thymus gland. The second series of experiments included leukemia induced in ovariectomized ICRC mice with 20-methylcholanthrene (MCA), pituitary transplants, and ovarian hormones (estradiol and estradiol-progesterone). In ovariectomized ICRC mice, leukemic lesions induced by MCA or pituitary transplants, or by MCA and pituitary transplants, showed type C virus particles and, in most cases, intracisternal type A particles. In leukemia induced in ovariectomized ICRC mice by MCA and estradiol, numerous intracytoplasmic type A particles were observed but no type C virus particles

  9. Radioimmunoassay and characterization of woodchuck hepatitis virus core antigen and antibody

    Energy Technology Data Exchange (ETDEWEB)

    Ponzetto, A; Cote, P J; Ford, E C; Engle, R; Gerin, J L; Cicmanec, J; Shapiro, M; Purcell, R H

    1985-06-01

    Solid-phase radioimmunoassays for woodchuck hepatitis virus core antigen (WHcAg) and antibody (anti-WHc) were developed. WHcAg in woodchuck liver homogenates was characterized by ultracentrifugation in CsCl gradients; both heavy and light cores were obtained from the liver of an animal during acute WHV infection, which is consistent with observations in hepatitis B virus infection in man. Endpoint titers of anti-WHc were higher in chronic WHV carriers than in animals recovered from acute infections. Both IgM and IgG anti-WHc antibodies were produced by infected woodchucks. A survey of colony woodchucks demonstrated that 88/89 animals having one or more markers of past or ongoing WHV infection were positive for anti-WHc. Thus, serum anti-WHc appears to be a sensitive marker of WHV infection.

  10. [Monoclonal antibodies ICO-02 to blast cell antigens in patients with chronic myeloleukemia in blast crisis].

    Science.gov (United States)

    Baryshnikov, A Iu

    1984-01-01

    Mice were immunized with blood cells of a patient with chronic granulocytic leukemia, and their cells were subsequently used for the preparation of hybridoma ICO-02. This hybridoma is continuously producing monoclonal antibodies which reacted with cells in 4 out of 13 patients with blastic crisis of chronic granulocytic leukemia and in 6 out of 38 patients with acute lymphoblastic leukemia. Antibodies reacted with blast cells in 2 out of 3 patients with undifferentiated blastic crisis of chronic myelocytic leukemia and in 2 out of 5 patients with lymphoid variant of blastic crisis of chronic granulocytic leukemia. Cells of 6 patients with acute lymphoblastic leukemia which reacted with the monoclonal antibodies had immunological markers of T lymphocytes bone-marrow precursors. Monoclonal antibodies did not react with cells of blood and bone marrow from healthy people and from patients with chronic lymphocytic leukemia, acute myeloblastic leukemia, acute myelomonocytic leukemia, acute monoblastic leukemia and lymphosarcoma.

  11. A rapid radioimmunoassay using 125I-labeled staphylococcal protein A for antibody to varicella-zoster virus

    International Nuclear Information System (INIS)

    Richman, D.D.; Cleveland, P.H.; Oxman, M.N.; Zaia, J.A.

    1981-01-01

    A sensitive radioimmunoassay for serum antibody to varicella-zoster virus is described; it uses 125I-labeled staphylococcal protein A and a specially designed immunofiltration apparatus. The assay accurately distinguishes between individuals who are susceptible and those who are immune to infection with varicella-zoster virus. In addition, it can detect passive antibody in recipients of varicella-zoster immune globulin. This radioimmunoassay also detects the heterologous antibody responses that occasionally occur in patients infected with herpes simplex virus, which also have been detected by other antibody assays. The particular advantages of this assay are the use of noninfectious reagents, the speed of execution (less than 3 hr), the requirement for only small quantities of serum (30 microliters), the objectivity of end-point determination, and the capability of screening large numbers of sera. Consequently, this radioimmunoassay is especially useful for the rapid identification of susceptible individuals, which is essential for the appropriate management of patients and hospital personnel after exposure to varicella

  12. Pichia pastoris-Expressed Bivalent Virus-Like Particulate Vaccine Induces Domain III-Focused Bivalent Neutralizing Antibodies without Antibody-Dependent Enhancement in Vivo

    OpenAIRE

    Rahul Shukla; Ravi K. Rajpoot; Upasana Arora; Ankur Poddar; Sathyamangalam Swaminathan; Navin Khanna; Navin Khanna; Navin Khanna

    2018-01-01

    Dengue, a significant public health problem in several countries around the world, is caused by four different serotypes of mosquito-borne dengue viruses (DENV-1, -2, -3, and -4). Antibodies to any one DENV serotype which can protect against homotypic re-infection, do not offer heterotypic cross-protection. In fact, cross-reactive antibodies may augment heterotypic DENV infection through antibody-dependent enhancement (ADE). A recently launched live attenuated vaccine (LAV) for dengue, which ...

  13. Helicobacter pylori, hepatitis viruses A, C, E antibodies and HBsAg-prevalence and associated risk factors in pediatric communities of karachi

    International Nuclear Information System (INIS)

    Aziz, S.; Muzzafar, R.; Hafiz, S.; Abbas, Z.; Zafar, M.N.; Naqvi, S.A.A.; Rizvi, S.A.U.H.

    2007-01-01

    To document the prevalence of Helicobacter pylori (H. pylori), Hepatitis A virus (HAV), Hepatitis C virus (HCV), Hepatitis E virus (HEV) antibodies and Hepatitis B virus surface antigen (HBsAg), in the pediatric age group of low socioeconomic urban communities of Karachi and to identify risk factors associated with these infections. Three hundred and eighty children, ages 5 months to 15 years were investigated. Venous blood samples were collected and questionnaire filled on sociodemographic characteristics (family income, number of dependents in the family, area of living, number of people per room per house, and number of children sharing bed with parents and siblings). Gastrointestinal symptoms were recorded. Anti-HAV IgG (Hepatitis A virus IgG antibody), anti-HCV (Hepatitis C virus antibody), anti-HEV (Hepatitis E antibodies) and HBsAg, were analyzed by enzyme immunoassays (EIAs). Samples were also screened for anti-HIV1/2 (human immunodeficiency virus 1 and 2 antibodies by EIA. IgG antibodies against H. pylori were detected by immunochromatography. A correlation between increasing age and seroconversion was seen for hepatotropic viruses. At 14 years and above,100% of the children were found to be positive for anti-HAV, 26% for anti-HEV, and 1.4%, for anti-HCV while HBsAg was positive in 1.9%. H. pylori infection did not show a significant increase with age. Both anti-HAV and anti-H. pylori were present simultaneously in 30% of the population investigated. With age, increasing number of children acquired antibodies against hepatotropic viruses and H. pylori. Occurrence of HBsAg and anti-HEV at a later age suggests horizontal, rather than vertical transmission. (author)

  14. Rapid Identification of Dengue Virus Serotypes Using Monoclonal Antibodies in an Indirect Immunofluorescence Test.

    Science.gov (United States)

    1982-06-18

    encephalitis(TBH-28), West Nile(E-101), Yellow fever(French neurotropic and 17D strains), and Zika . Two Sandfly Fever viruses (213452 and Candiru) were...were provided as first passage isolates ( Aedes pseudoscutellaris cells, AP-61) or human serum from recent dengue virus patients. African isolates... viruses of the Phlebovirus genus (Table 1). Several monoclonal antibody preparations reacted solely with dengue virus serotypes. Two preparations (13E7 and

  15. Epstein-Barr virus but not cytomegalovirus is associated with reduced vaccine antibody responses in Gambian infants.

    Directory of Open Access Journals (Sweden)

    Beth Holder

    2010-11-01

    Full Text Available Epstein-Barr virus (EBV and cytomegalovirus (CMV are persistent herpesviruses that have various immunomodulatory effects on their hosts. Both viruses are usually acquired in infancy in Sub-Saharan Africa, a region where childhood vaccines are less effective than in high income settings. To establish whether there is an association between these two observations, we tested the hypothesis that infection with one or both viruses modulate antibody responses to the T-cell independent meningococcal polysaccharide vaccine and the T-cell dependent measles vaccines.Infection with EBV and CMV was diagnosed by the presence of virus-specific IgM in the peripheral blood or by the presence of IgG at higher levels than that found in umbilical cord blood. Anti-meningococcus IgG and IgM were quantified by ELISA. Anti-measles antibody responses were quantified by haemagglutinin antibody inhibition assay. Infants infected with EBV had reduced IgG and IgM antibody responses to meningococcal polysaccharides and to measles vaccine. Infection with CMV alone predicted no changes in the response to meningococcal polysaccharide. While CMV alone had no discernable effect on the antibody response to measles, the response of infants infected with both CMV and EBV was similar to that of infants infected with neither, suggesting that the effects of CMV infection countered the effects of EBV on measles antibody responses.The results of this exploratory study indicate that infection with EBV is associated with reduced antibody responses to polysaccharides and to measles vaccine, but suggest that the response to T-cell dependent antigens such as measles haemagglutinin may be restored by infection with CMV.

  16. Bluetongue virus: comparative evaluation of enzyme-linked immunosorbent assay, immunodiffusion, and serum neutralization for detection of viral antibodies.

    OpenAIRE

    Poli, G; Stott, J; Liu, Y S; Manning, J S

    1982-01-01

    Comparative studies on the detection of bovine serum immunoglobulin G antibodies to bluetongue virus with an enzyme-linked immunosorbent assay, an immunodiffusion method, and a serum neutralization assay demonstrated complete concordance between the enzyme-linked immunosorbent assay and the serum neutralization assay results. However, the immunodiffusion method failed to detect bluetongue virus antibody in a substantial number of sera found to possess bluetongue virus immunoglobulin G with th...

  17. Antibodies against Hepatitis A and Hepatitis B Virus in Intravenous Immunoglobulin Products.

    Science.gov (United States)

    Lee, Soyoung; Kim, Han Wool; Kim, Kyung Hyo

    2016-12-01

    The worldwide seroprevalence of hepatitis A virus (HAV) and hepatitis B virus (HBV) has changed over the last two decades, indicating a declining incidence of HAV and HBV infections. Therefore, vaccinations against HAV and HBV are recommended for unimmunized people before traveling to an endemic area. Unfortunately, primary antibody deficiency (PAD) patients can only obtain humoral immunity through intravenous immunoglobulin G (IVIG) replacement and not from vaccination because of a defect in antibody production. However, few studies have analyzed the titers of antibodies against HAV or HBV in IVIG products. In this study, the titers of anti-HAV and anti-HBs antibodies were measured in nineteen lots of IVIG products from five manufacturers from three countries (A, B from Korea; C, D from Japan; and E from the USA), and trough titers in plasma were estimated. Concentrations of anti-HAV antibody ranged from 1,888-8,927 mIU/mL and estimated trough titers exceeded the minimal protective value in all evaluated IVIG products. Concentrations of anti-HBs antibody ranged from 438-965 mIU/mL in products A and B and were 157, 123, and 1,945 mIU/mL in products C, D, and E, respectively. Estimated trough titers in products A, B, and E exceeded the minimal protective value but those in products C and D did not reach this threshold. These data demonstrated that available IVIG products generally provide sufficient antibodies against HAV and HBV to protect patients with PAD, although the trough concentrations of anti-HBs antibody in two IVIG products did not reach the minimum protective value.

  18. Comparison of the geographical distribution of feline immunodeficiency virus and feline leukemia virus infections in the United States of America (2000-2011).

    Science.gov (United States)

    Chhetri, Bimal K; Berke, Olaf; Pearl, David L; Bienzle, Dorothee

    2013-01-05

    Although feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) have similar risk factors and control measures, infection rates have been speculated to vary in geographic distribution over North America. Since both infections are endemic in North America, it was assumed as a working hypothesis that their geographic distributions were similar. Hence, the purpose of this exploratory analysis was to investigate the comparative geographical distribution of both viral infections. Counts of FIV (n=17,108) and FeLV (n=30,017) positive serology results (FIV antibody and FeLV ELISA) were obtained for 48 contiguous states and District of Columbia of the United States of America (US) from the IDEXX Laboratories website. The proportional morbidity ratio of FIV to FeLV infection was estimated for each administrative region and its geographic distribution pattern was visualized by a choropleth map. Statistical evidence of an excess in the proportional morbidity ratio from unity was assessed using the spatial scan test under the normal probability model. This study revealed distinct spatial distribution patterns in the proportional morbidity ratio suggesting the presence of one or more relevant and geographically varying risk factors. The disease map indicates that there is a higher prevalence of FIV infections in the southern and eastern US compared to FeLV. In contrast, FeLV infections were observed to be more frequent in the western US compared to FIV. The respective excess in proportional morbidity ratio was significant with respect to the spatial scan test (p < 0.05). The observed variability in the geographical distribution of the proportional morbidity ratio of FIV to FeLV may be related to the presence of an additional or unique, but yet unknown, spatial risk factor. Putative factors may be geographic variations in specific virus strains and rate of vaccination. Knowledge of these factors and the geographical distributions of these infections can inform

  19. Association between psychopathic disorder and serum antibody to herpes simplex virus (type 1).

    Science.gov (United States)

    Cleobury, J F; Skinner, G R; Thouless, M E; Wildy, P

    1971-02-20

    The sera of a small of patients has been examined for herpes simplex virus antibody. Three clinically-defined groups of patients were compared: (a) aggressive psychopaths, (b) psychiatric controls, and (c) general hospital patients. The first group had an unusually high average kinetic neutralization constant against type 1 herpes simplex virus.

  20. Myelodysplastic syndromes and acute myeloid leukemia in cats infected with feline leukemia virus clone33 containing a unique long terminal repeat.

    Science.gov (United States)

    Hisasue, Masaharu; Nagashima, Naho; Nishigaki, Kazuo; Fukuzawa, Isao; Ura, Shigeyoshi; Katae, Hiromi; Tsuchiya, Ryo; Yamada, Takatsugu; Hasegawa, Atsuhiko; Tsujimoto, Hajime

    2009-03-01

    Feline leukemia virus (FeLV) clone33 was obtained from a domestic cat with acute myeloid leukemia (AML). The long terminal repeat (LTR) of this virus, like the LTRs present in FeLV from other cats with AML, differs from the LTRs of other known FeLV in that it has 3 tandem direct 47-bp repeats in the upstream region of the enhancer (URE). Here, we injected cats with FeLV clone33 and found 41% developed myelodysplastic syndromes (MDS) characterized by peripheral blood cytopenias and dysplastic changes in the bone marrow. Some of the cats with MDS eventually developed AML. The bone marrow of the majority of cats with FeLV clone33 induced MDS produced fewer erythroid and myeloid colonies upon being cultured with erythropoietin or granulocyte-macrophage colony-stimulating factor (GM-SCF) than bone marrow from normal control cats. Furthermore, the bone marrow of some of the cats expressed high-levels of the apoptosis-related genes TNF-alpha and survivin. Analysis of the proviral sequences obtained from 13 cats with naturally occurring MDS reveal they also bear the characteristic URE repeats seen in the LTR of FeLV clone33 and other proviruses from cats with AML. Deletions and mutations within the enhancer elements are frequently observed in naturally occurring MDS as well as AML. These results suggest that FeLV variants that bear URE repeats in their LTR strongly associate with the induction of both MDS and AML in cats.

  1. Study of the titers of Anti-Epstein-Barr virus antibodies in the sera of atomic bomb survivors

    Energy Technology Data Exchange (ETDEWEB)

    Akiyama, Mitoshi; Kusunoki, Yoichiro; Kyoizumi, Seishi; Ozaki, Kyoko; Mizuno, Shoichi; Cologne, J.B.

    1993-12-31

    Antibody titers to Epstein-Barr virus antigens were determined in the sera of 372 atomic bomb survivors to evaluate the effect of the previous radiation exposure on immune competence against the latent infection of the virus. The proportion of persons with high titers ({>=} 1:40) of IgG antibodies to the early antigen was significantly elevated in the exposed survivors. Furthermore, the distribution of IgM titers against the viral capsid antigen was significantly affected by radiation dose with an increased occurrence of titers of 1:5 and 1:10 in the exposed persons, although the dose effect was only marginally suggestive when persons with rheumatoid factor were eliminated from the analysis. These results suggest that reactivation of Epstein-Barr virus in the latent stage occurs more frequently in the survivors, even though this might not be affected by the radiation dose. Otherwise, there was neither an increased trend in the prevalence of high titers ({>=} 1:640) of IgG antibodies to the viral capsid antigen among the exposed people nor a correlation between the radiation exposure and distributions of titers of IgA antibodies to the viral capsid antigen or antibodies to the anti-Epstein-Barr virus-associated nuclear antigen. (author).

  2. Study of the titers of Anti-Epstein-Barr virus antibodies in the sera of atomic bomb survivors

    International Nuclear Information System (INIS)

    Akiyama, Mitoshi; Kusunoki, Yoichiro; Kyoizumi, Seishi; Ozaki, Kyoko; Mizuno, Shoichi; Cologne, J.B.

    1993-01-01

    Antibody titers to Epstein-Barr virus antigens were determined in the sera of 372 atomic bomb survivors to evaluate the effect of the previous radiation exposure on immune competence against the latent infection of the virus. The proportion of persons with high titers (≥ 1:40) of IgG antibodies to the early antigen was significantly elevated in the exposed survivors. Furthermore, the distribution of IgM titers against the viral capsid antigen was significantly affected by radiation dose with an increased occurrence of titers of 1:5 and 1:10 in the exposed persons, although the dose effect was only marginally suggestive when persons with rheumatoid factor were eliminated from the analysis. These results suggest that reactivation of Epstein-Barr virus in the latent stage occurs more frequently in the survivors, even though this might not be affected by the radiation dose. Otherwise, there was neither an increased trend in the prevalence of high titers (≥ 1:640) of IgG antibodies to the viral capsid antigen among the exposed people nor a correlation between the radiation exposure and distributions of titers of IgA antibodies to the viral capsid antigen or antibodies to the anti-Epstein-Barr virus-associated nuclear antigen. (author)

  3. High-resolution Antibody Array Analysis of Childhood Acute Leukemia Cells

    Czech Academy of Sciences Publication Activity Database

    Kanderová, V.; Kuzilkova, D.; Stuchlý, J.; Vašková, M.; Brdička, Tomáš; Fišer, K.; Hrušák, O.; Lund-Johansen, F.; Kalina, T.

    2016-01-01

    Roč. 15, č. 4 (2016), s. 1246-1261 ISSN 1535-9476 R&D Projects: GA MŠk 2B06064 Institutional support: RVO:68378050 Keywords : acute lymphoblastic-leukemia * acute promyelocytic leukemia * cytometric immunobead assay * caspase-dependent cleavage * acute myeloid-leukemia * gene-expression * fusion proteins * flow-cytometry * pcr data * b-cells Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 6.540, year: 2016

  4. Evaluating enzootic bovine leukemia virus infection by means of molecular probe compared with the results of serological tests

    International Nuclear Information System (INIS)

    Reichert, M.; Grundbock, J.; Rulka, J.; Kozaczynska, B.; Stec, J.

    1994-01-01

    The present studies were aimed at determining the relation between the finding obtained by means of serological tests and the specific molecular probe. Serological tests were performed according to the methods recommended by the Polish Ministry of Agriculture; ELISA was run with ''Bioveta'' and ''Rhone Merieux'' kits and the AGID test was performed with EBL antigen made in our laboratory. The molecular probe was prepared from the previously cloned provirus DNA of EBL virus. The EBL provirus was detected in 28 samples taken from 44 randomly selected cows in three herds on which a leukemia eradication programme was in process. Three sera out of 28 positive reacting animals were negative in AGID test and only one serum in ELISA. The results indicate that the use of a specific molecular probe has some advantages in the diagnosis of latent virus infections. Besides, it can be applied in the studies on the pathogenesis of enzootic bovine leukemia. (author). 13 refs, 1 fig., 1 tab

  5. Influenza virus neutralizing antibodies and IgG isotype profiles after immunization of mice with influenza A subunit vaccine using various adjuvants

    NARCIS (Netherlands)

    Benne, CA; Harmsen, M; vanderGraaff, W; Verheul, AFM; Snippe, H; Kraaijeveld, CA

    The influence of various adjuvants on the development of influenza virus neutralizing antibodies and distribution of anti-influenza virus IgG isotypes after immunization of mice with influenza A (H3N2) subunit vaccine was investigated. Serum titres of influenza virus neutralizing antibodies and

  6. A Potent Virus-Specific Antibody-Secreting Cell Response to Acute Enterovirus 71 Infection in Children.

    Science.gov (United States)

    Huang, Kuan-Ying Arthur; Lin, Jainn-Jim; Chiu, Cheng-Hsun; Yang, Shuan; Tsao, Kuo-Chien; Huang, Yhu-Chering; Lin, Tzou-Yien

    2015-09-01

    Enterovirus 71 (EV71) remains a leading pathogen for acute infectious diseases in children, especially in Asia. The cellular basis for establishing a virus-specific antibody response to acute EV71 infections is unclear in children. We studied the magnitude of virus-specific antibody-secreting B cells (ASCs) and its relationship with serological response, clinical parameters, and virological parameters among children with laboratory-confirmed EV71 infection. A potent EV71 genogroup B- and virus-specific ASC response was detected in the first week of illness among genotype B5 EV71-infected children. The cross-reactive EV71-specific ASC response to genogroup C viral antigens composed about 10% of the response. The EV71-specific ASC response in children aged ≥3 years produced immunoglobulin G predominantly, but immunoglobulin M was predominant in younger children. Proliferation marker was expressed by the majority of circulating ASCs in the acute phase of EV71 infection. Virus-specific ASC responses significantly correlated with throat viral load, fever duration, and serological genogroup-specific neutralization titer. The presence of a virus-specific ASC response serves an early cellular marker of an EV71-specific antibody response. Further detailed study of EV71-specific ASCs at the monoclonal level is crucial to delineate the specificity and function of antibody immunity in children. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  7. Effective surveillance for early classical swine fever virus detection will utilize both virus and antibody detection capabilities.

    Science.gov (United States)

    Panyasing, Yaowalak; Kedkovid, Roongtham; Thanawongnuwech, Roongroje; Kittawornrat, Apisit; Ji, Ju; Giménez-Lirola, Luis; Zimmerman, Jeffrey

    2018-03-01

    Early recognition and rapid elimination of infected animals is key to controlling incursions of classical swine fever virus (CSFV). In this study, the diagnostic characteristics of 10 CSFV assays were evaluated using individual serum (n = 601) and/or oral fluid (n = 1417) samples collected from -14 to 28 days post inoculation (DPI). Serum samples were assayed by virus isolation (VI), 2 commercial antigen-capture enzyme-linked immunosorbent assays (ELISA), virus neutralization (VN), and 3 antibody ELISAs. Both serum and oral fluid samples were tested with 3 commercial real-time reverse transcription-polymerase chain reaction (rRT-PCR) assays. One or more serum samples was positive by VI from DPIs 3 to 21 and by antigen-capture ELISAs from DPIs 6 to 17. VN-positive serum samples were observed at DPIs ≥ 7 and by antibody ELISAs at DPIs ≥ 10. CSFV RNA was detected in serum samples from DPIs 2 to 28 and in oral fluid samples from DPIs 4 to 28. Significant differences in assay performance were detected, but most importantly, no single combination of sample and assay was able to dependably identify CSFV-inoculated pigs throughout the 4-week course of the study. The results show that effective surveillance for CSFV, especially low virulence strains, will require the use of PCR-based assays for the detection of early infections (<14 days) and antibody-based assays, thereafter. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Anti-Idiotypic Antibodies Specific to prM Monoantibody Prevent Antibody Dependent Enhancement of Dengue Virus Infection

    Directory of Open Access Journals (Sweden)

    Miao Wang

    2017-05-01

    Full Text Available Dengue virus (DENV co-circulates as four serotypes (DENV1-4. Primary infection only leads to self-limited dengue fever. But secondary infection with another serotype carries a higher risk of increased disease severity, causing life-threatening dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS. Serotype cross-reactive antibodies facilitate DENV infection in Fc-receptor-bearing cells by promoting virus entry via Fcγ receptors (FcγR, a process known as antibody dependent enhancement (ADE. Most studies suggested that enhancing antibodies were mainly specific to the structural premembrane protein (prM of DENV. However, there is still no effective drugs or vaccines to prevent ADE. In this study, we firstly confirmed that both DENV-2 infected human sera (anti-DENV-2 and DENV-2 prM monoclonal antibody (prM mAb could significantly enhance DENV-1 infection in K562 cells. Then we developed anti-idiotypic antibodies (prM-AIDs specific to prM mAb by immunizing of Balb/c mice. Results showed that these polyclonal antibodies can dramatically reduce ADE phenomenon of DENV-1 infection in K562 cells. To further confirm the anti-ADE effect of prM-AIDs in vivo, interferon-α and γ receptor-deficient mice (AG6 were used as the mouse model for DENV infection. We found that administration of DENV-2 prM mAb indeed caused a higher DENV-1 titer as well as interleukin-10 (IL-10 and alaninea minotransferase (ALT in mice infected with DENV-1, similar to clinical ADE symptoms. But when we supplemented prM-AIDs to DENV-1 challenged AG6 mice, the viral titer, IL-10 and ALT were obviously decreased to the negative control level. Of note, the number of platelets in peripheral blood of prM-AIDs group were significantly increased at day 3 post infection with DENV-1 compared that of prM-mAb group. These results confirmed that our prM-AIDs could prevent ADE not only in vitro but also in vivo, suggested that anti-idiotypic antibodies might be a new choice to be considered to

  9. Anti-Idiotypic Antibodies Specific to prM Monoantibody Prevent Antibody Dependent Enhancement of Dengue Virus Infection.

    Science.gov (United States)

    Wang, Miao; Yang, Fan; Huang, Dana; Huang, Yalan; Zhang, Xiaomin; Wang, Chao; Zhang, Shaohua; Zhang, Renli

    2017-01-01

    Dengue virus (DENV) co-circulates as four serotypes (DENV1-4). Primary infection only leads to self-limited dengue fever. But secondary infection with another serotype carries a higher risk of increased disease severity, causing life-threatening dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). Serotype cross-reactive antibodies facilitate DENV infection in Fc-receptor-bearing cells by promoting virus entry via Fcγ receptors (FcγR), a process known as antibody dependent enhancement (ADE). Most studies suggested that enhancing antibodies were mainly specific to the structural premembrane protein (prM) of DENV. However, there is still no effective drugs or vaccines to prevent ADE. In this study, we firstly confirmed that both DENV-2 infected human sera (anti-DENV-2) and DENV-2 prM monoclonal antibody (prM mAb) could significantly enhance DENV-1 infection in K562 cells. Then we developed anti-idiotypic antibodies (prM-AIDs) specific to prM mAb by immunizing of Balb/c mice. Results showed that these polyclonal antibodies can dramatically reduce ADE phenomenon of DENV-1 infection in K562 cells. To further confirm the anti-ADE effect of prM-AIDs in vivo , interferon-α and γ receptor-deficient mice (AG6) were used as the mouse model for DENV infection. We found that administration of DENV-2 prM mAb indeed caused a higher DENV-1 titer as well as interleukin-10 (IL-10) and alaninea minotransferase (ALT) in mice infected with DENV-1, similar to clinical ADE symptoms. But when we supplemented prM-AIDs to DENV-1 challenged AG6 mice, the viral titer, IL-10 and ALT were obviously decreased to the negative control level. Of note, the number of platelets in peripheral blood of prM-AIDs group were significantly increased at day 3 post infection with DENV-1 compared that of prM-mAb group. These results confirmed that our prM-AIDs could prevent ADE not only in vitro but also in vivo , suggested that anti-idiotypic antibodies might be a new choice to be considered to treat

  10. Screening test for neutralizing antibodies against yellow fever virus, based on a flavivirus pseudotype.

    Directory of Open Access Journals (Sweden)

    Séverine Mercier-Delarue

    Full Text Available Given the possibility of yellow fever virus reintroduction in epidemiologically receptive geographic areas, the risk of vaccine supply disruption is a serious issue. New strategies to reduce the doses of injected vaccines should be evaluated very carefully in terms of immunogenicity. The plaque reduction test for the determination of neutralizing antibodies (PRNT is particularly time-consuming and requires the use of a confinement laboratory. We have developed a new test based on the use of a non-infectious pseudovirus (WN/YF17D. The presence of a reporter gene allows sensitive determination of neutralizing antibodies by flow cytometry. This WN/YF17D test was as sensitive as PRNT for the follow-up of yellow fever vaccinees. Both tests lacked specificity with sera from patients hospitalized for acute Dengue virus infection. Conversely, both assays were strictly negative in adults never exposed to flavivirus infection or vaccination, and in patients sampled some time after acute Dengue infection. This WN/YF17D test will be particularly useful for large epidemiological studies and for screening for neutralizing antibodies against yellow fever virus.

  11. In vivo neutralization of hepatitis B virus infection by an anti-preS1 humanized antibody in chimpanzees

    International Nuclear Information System (INIS)

    Hong, Hyo Jeong; Ryu, Chun Jeih; Hur, Hyangsuk; Kim, Seho; Oh, Han Kyu; Oh, Mee Sook; Park, Song Yong

    2004-01-01

    Previously, we generated a murine monoclonal antibody (mAb), KR127, that recognizes amino acids (aa) 37-45 of the preS1 of hepatitis B virus (HBV). In this study, we have constructed a humanized version of KR127 and evaluated its HBV-neutralizing activity in chimpanzees. A study chimpanzee was given a single intravenous dose of the humanized antibody, followed by intravenous challenge with adr subtype of wild type HBV, while a control chimpanzee was only challenged with the virus. The result showed that the study chimpanzee did not develop HBV infection during 1 year, while the control chimpanzee was infected, indicating that the humanized antibody exhibited in vivo virus-neutralizing activity and thus protected the chimpanzee from HBV infection. In addition, the humanized antibody bound to the preS1 of all subtypes of HBV. We first demonstrate that an anti-preS1 mAb can neutralize HBV infection in vivo. This humanized antibody will be useful for the immunoprophylaxis of HBV infection

  12. Multicentric T-cell lymphoma associated with feline leukemia virus infection in a captive namibian cheetah (Acinonyx jubatus).

    Science.gov (United States)

    Marker, Laurie; Munson, Linda; Basson, Peter A; Quackenbush, Sandra

    2003-07-01

    This case report describes a multicentric lymphoma in a 4 yr old female wildborn captive cheetah (Acinonyx jubatus) in Namibia after being housed in an enclosure adjacent to a feline leukemia virus (FeLV) infected cheetah that had previously been in contact with domestic cats. The year prior to the onset of clinical signs, the wild-born cheetah was FeLV antigen negative. The cheetah subsequently developed lymphoma, was found to be infected with FeLV, and then rapidly deteriorated and died. At necropsy, the liver, spleen, lymph nodes, and multiple other organs were extensively infiltrated with neoplastic T-lymphocytes. Feline leukemia virus DNA was identified in neoplastic lymphocytes from multiple organs by polymerase chain reaction and Southern blot analysis. Although the outcome of infection in this cheetah resembles that of FeLV infections in domestic cats, the transmission across an enclosure fence was unusual and may indicate a heightened susceptibility to infection in cheetahs. Caution should be exercised in holding and translocating cheetahs where contact could be made with FeLV-infected domestic, feral, or wild felids.

  13. Limited interlaboratory comparison of Schmallenberg virus antibody detection in serum samples

    DEFF Research Database (Denmark)

    van der Poel, W. H. M.; Cay, B.; Zientara, S.

    2014-01-01

    Eight veterinary institutes in seven different countries in Europe participated in a limited interlaboratory comparison trial to evaluate laboratory performances of Schmallenberg virus (SBV) antibody detection in serum. Seven different sheep sera and three different cattle sera were circulated, a...

  14. Human T-cell leukemia virus types I and II exhibit different DNase I protection patterns

    International Nuclear Information System (INIS)

    Altman, R.; Harrich, D.; Garcia, J.A.; Gaynor, R.B.

    1988-01-01

    Human T-cell leukemia virus types I (HTLV-I) and II (HTLV-II) are human retroviruses which normally infect T-lymphoid cells. HTLV-I infection is associated with adult T-cell leukemia-lymphoma, and HTLV-II is associated with an indolent form of hairy-cell leukemia. To identify potential transcriptional regulatory elements of these two related human retroviruses, the authors performed DNase I footprinting of both the HTLV-I and HTLV-II long terminal repeats (LTRs) by using extracts prepared from uninfected T cells, HTLV-I and HTLV-II transformed T cells, and HeLa cells. Five regions of the HTLV-I LTR and three regions of the HTLV-II LTR showed protection by DNase I footprinting. All three of the 21-base-pair repeats previously shown to be important in HTLV transcriptional regulation were protected in the HTLV-I LTR, whereas only one of these repeats was protected in the HTLV-II LTR. Several regions exhibited altered protection in extracts prepared from lymphoid cells as compared with HeLa cells, but there were minimal differences in the protection patterns between HTLV-infected and uninfected lymphoid extracts. A number of HTLV-I and HTLV-II LTR fragments which contained regions showing protection in DNase I footprinting were able to function as inducible enhancer elements in transient CAT gene expression assays in the presence of the HTLV-II tat protein. The alterations in the pattern of the cellular proteins which bind to the HTLV-I and HTLV-II LTRs may in part be responsible for differences in the transcriptional regulation of these two related viruses

  15. Viral excretion and antibody titers in children infected with hepatitis A virus from an orphanage in western India.

    Science.gov (United States)

    Hundekar, Supriya; Thorat, Neeta; Gurav, Yogesh; Lole, Kavita

    2015-12-01

    Hepatitis A is endemic in India and mainly causes sporadic infections. However, children in childcare centers, schools and orphanages are vulnerable to common-source outbreaks as they have naive hosts. To investigate hepatitis A outbreak in an orphanage from Pune, India. Monitoring of virus excretion and anti-HAV antibody levels in hepatitis A virus (HAV) infected children. The orphanage housed 93 children of the age 1 month-6.5 years. Analysis of the collected serum (n=78) and stool samples (n=63) revealed 20 children to be either positive for anti-HAV IgM antibodies or excreting HAV, 14 being symptomatic and 6 asymptomatic, while 32 were already anti-HAV IgG positive either due to past HAV exposure (n=7, mean log antibody titers: 2.96) or maternal antibodies (n=25, mean log antibody titers: 1.13). Serum samples, taken 4 weeks apart, did not show any significant difference in the IgM and IgG antibody levels either. However, virus excretion decreased significantly after 15 days in symptomatic children (mean log HAV RNA copies/ml 1.03+0.30), while asymptomatic children continued to excrete higher viral loads, at constant levels (mean log HAV RNA copies/ml 2.33+0.33), for up to 90 days. Though virus excretion continued up to 90 days in all HAV infected children, asymptomatic children excreted higher viral loads for longer period and hence can contribute significantly in person-to-person virus transmission. All children should be vaccinated in such set ups. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. A novel H6N1 virus-like particle vaccine induces long-lasting cross-clade antibody immunity against human and avian H6N1 viruses.

    Science.gov (United States)

    Yang, Ji-Rong; Chen, Chih-Yuan; Kuo, Chuan-Yi; Cheng, Chieh-Yu; Lee, Min-Shiuh; Cheng, Ming-Chu; Yang, Yu-Chih; Wu, Chia-Ying; Wu, Ho-Sheng; Liu, Ming-Tsan; Hsiao, Pei-Wen

    2016-02-01

    Avian influenza A(H6N1) virus is one of the most common viruses isolated from migrating birds and domestic poultry in many countries. The first and only known case of human infection by H6N1 virus in the world was reported in Taiwan in 2013. This led to concern that H6N1 virus may cause a threat to public health. In this study, we engineered a recombinant H6N1 virus-like particle (VLP) and investigated its vaccine effectiveness compared to the traditional egg-based whole inactivated virus (WIV) vaccine. The H6N1-VLPs exhibited similar morphology and functional characteristics to influenza viruses. Prime-boost intramuscular immunization in mice with unadjuvanted H6N1-VLPs were highly immunogenic and induced long-lasting antibody immunity. The functional activity of the VLP-elicited IgG antibodies was proved by in vitro seroprotective hemagglutination inhibition and microneutralization titers against the homologous human H6N1 virus, as well as in vivo viral challenge analyses which showed H6N1-VLP immunization significantly reduced viral load in the lung, and protected against human H6N1 virus infection. Of particular note, the H6N1-VLPs but not the H6N1-WIVs were able to confer cross-reactive humoral immunity; antibodies induced by H6N1-VLP vaccine robustly inhibited the hemagglutination activities and in vitro replication of distantly-related heterologous avian H6N1 viruses. Furthermore, the H6N1-VLPs were found to elicit significantly greater anti-HA2 antibody responses in immunized mice than H6N1-WIVs. Collectively, we demonstrated for the first time a novel H6N1-VLP vaccine that effectively provides broadly protective immunity against both human and avian H6N1 viruses. These results, which uncover the underlying mechanisms for induction of wide-range immunity against influenza viruses, may be useful for future influenza vaccine development. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Initiating a watch list for Ebola virus antibody escape mutations

    Directory of Open Access Journals (Sweden)

    Craig R. Miller

    2016-02-01

    Full Text Available The 2014 Ebola virus (EBOV outbreak in West Africa is the largest in recorded history and resulted in over 11,000 deaths. It is essential that strategies for treatment and containment be developed to avoid future epidemics of this magnitude. With the development of vaccines and antibody-based therapies using the envelope glycoprotein (GP of the 1976 Mayinga strain, one important strategy is to anticipate how the evolution of EBOV might compromise these efforts. In this study we have initiated a watch list of potential antibody escape mutations of EBOV by modeling interactions between GP and the antibody KZ52. The watch list was generated using molecular modeling to estimate stability changes due to mutation. Every possible mutation of GP was considered and the list was generated from those that are predicted to disrupt GP-KZ52 binding but not to disrupt the ability of GP to fold and to form trimers. The resulting watch list contains 34 mutations (one of which has already been seen in humans at six sites in the GP2 subunit. Should mutations from the watch list appear and spread during an epidemic, it warrants attention as these mutations may reflect an evolutionary response from the virus that could reduce the effectiveness of interventions such as vaccination. However, this watch list is incomplete and emphasizes the need for more experimental structures of EBOV interacting with antibodies in order to expand the watch list to other epitopes. We hope that this work provokes experimental research on evolutionary escape in both Ebola and other viral pathogens.

  18. Initiating a watch list for Ebola virus antibody escape mutations.

    Science.gov (United States)

    Miller, Craig R; Johnson, Erin L; Burke, Aran Z; Martin, Kyle P; Miura, Tanya A; Wichman, Holly A; Brown, Celeste J; Ytreberg, F Marty

    2016-01-01

    The 2014 Ebola virus (EBOV) outbreak in West Africa is the largest in recorded history and resulted in over 11,000 deaths. It is essential that strategies for treatment and containment be developed to avoid future epidemics of this magnitude. With the development of vaccines and antibody-based therapies using the envelope glycoprotein (GP) of the 1976 Mayinga strain, one important strategy is to anticipate how the evolution of EBOV might compromise these efforts. In this study we have initiated a watch list of potential antibody escape mutations of EBOV by modeling interactions between GP and the antibody KZ52. The watch list was generated using molecular modeling to estimate stability changes due to mutation. Every possible mutation of GP was considered and the list was generated from those that are predicted to disrupt GP-KZ52 binding but not to disrupt the ability of GP to fold and to form trimers. The resulting watch list contains 34 mutations (one of which has already been seen in humans) at six sites in the GP2 subunit. Should mutations from the watch list appear and spread during an epidemic, it warrants attention as these mutations may reflect an evolutionary response from the virus that could reduce the effectiveness of interventions such as vaccination. However, this watch list is incomplete and emphasizes the need for more experimental structures of EBOV interacting with antibodies in order to expand the watch list to other epitopes. We hope that this work provokes experimental research on evolutionary escape in both Ebola and other viral pathogens.

  19. Comparison of the geographical distribution of feline immunodeficiency virus and feline leukemia virus infections in the United States of America (2000–2011

    Directory of Open Access Journals (Sweden)

    Chhetri Bimal K

    2013-01-01

    Full Text Available Abstract Background Although feline immunodeficiency virus (FIV and feline leukemia virus (FeLV have similar risk factors and control measures, infection rates have been speculated to vary in geographic distribution over North America. Since both infections are endemic in North America, it was assumed as a working hypothesis that their geographic distributions were similar. Hence, the purpose of this exploratory analysis was to investigate the comparative geographical distribution of both viral infections. Counts of FIV (n=17,108 and FeLV (n=30,017 positive serology results (FIV antibody and FeLV ELISA were obtained for 48 contiguous states and District of Columbia of the United States of America (US from the IDEXX Laboratories website. The proportional morbidity ratio of FIV to FeLV infection was estimated for each administrative region and its geographic distribution pattern was visualized by a choropleth map. Statistical evidence of an excess in the proportional morbidity ratio from unity was assessed using the spatial scan test under the normal probability model. Results This study revealed distinct spatial distribution patterns in the proportional morbidity ratio suggesting the presence of one or more relevant and geographically varying risk factors. The disease map indicates that there is a higher prevalence of FIV infections in the southern and eastern US compared to FeLV. In contrast, FeLV infections were observed to be more frequent in the western US compared to FIV. The respective excess in proportional morbidity ratio was significant with respect to the spatial scan test (p Conclusions The observed variability in the geographical distribution of the proportional morbidity ratio of FIV to FeLV may be related to the presence of an additional or unique, but yet unknown, spatial risk factor. Putative factors may be geographic variations in specific virus strains and rate of vaccination. Knowledge of these factors and the geographical

  20. Modulation of Dengue/Zika Virus Pathogenicity by Antibody-Dependent Enhancement and Strategies to Protect Against Enhancement in Zika Virus Infection

    Directory of Open Access Journals (Sweden)

    Rekha Khandia

    2018-04-01

    Full Text Available Antibody-dependent enhancement (ADE is a phenomenon in which preexisting poorly neutralizing antibodies leads to enhanced infection. It is a serious concern with mosquito-borne flaviviruses such as Dengue virus (DENV and Zika virus (ZIKV. In vitro experimental evidences have indicated the preventive, as well as a pathogenicity-enhancing role, of preexisting DENV antibodies in ZIKV infections. ADE has been confirmed in DENV but not ZIKV infections. Principally, the Fc region of the anti-DENV antibody binds with the fragment crystallizable gamma receptor (FcγR, and subsequent C1q interactions and immune effector functions are responsible for the ADE. In contrast to normal DENV infections, with ADE in DENV infections, inhibition of STAT1 phosphorylation and a reduction in IRF-1 gene expression, NOS2 levels, and RIG-1 and MDA-5 expression levels occurs. FcγRIIA is the most permissive FcγR for DENV-ADE, and under hypoxic conditions, hypoxia-inducible factor-1 alpha transcriptionally enhances expression levels of FcγRIIA, which further enhances ADE. To produce therapeutic antibodies with broad reactivity to different DENV serotypes, as well as to ZIKV, bispecific antibodies, Fc region mutants, modified Fc regions, and anti-idiotypic antibodies may be engineered. An in-depth understanding of the immunological and molecular mechanisms of DENV-ADE of ZIKV pathogenicity will be useful for the design of common and safe therapeutics and prophylactics against both viral pathogens. The present review discusses the role of DENV antibodies in modulating DENV/ZIKV pathogenicity/infection and strategies to counter ADE to protect against Zika infection.

  1. Seroprevalence immunodeficiency virus and feline leukemia in cats in Monteria, Córdoba SEROPREVALENCIA DEL VIRUS DE LEUCEMIA E INMUNODEFICIENCIA FELINA EN GATOS DE MONTERÍA, CÓRDOBA

    Directory of Open Access Journals (Sweden)

    Ríos Rincón Rodrigo Alexander

    2009-04-01

    Full Text Available The gradual increment of the feline population in Colombia and some countries is associated with presence of diseases that care produce animal health risk. The virus of immunodeficiency and the feline leukemia are the main retroviales diseases with high morbility and mortality in felines and they require of a right diagnostic that extend the felines’ life. A descriptive transversal cut study was done, 60 urban domestic cats of Montería were included, animals were from clinics, veterinarian consults and familiar houses. The simultaneous diagnostic of leukemia and feline immunodeficiency was carried out by using inmunoensayo SNAP combo FeLV Ag/FIV Ab (laboratories Idexx Toronto, Canadá in samples of serum and plasma. The animals were submitted to a physical and laboratory examination the population studied were 30 females and 30 males most of them minor of 2 years. Feline leukemia showed a seroprevalence of 23,3% (14/60, for feline immunodeficiency a seroprevalence of 1,6% (1/60, and the prevalence of double infection for feline leukemia and immunodeficiency was of 5% (3/60. The immunodeficiency’s virus and feline leukemia diagnostic was carry out for first time in the population of domestics cats in the city of Montería and it established a seroprevalence of 23,3% and 1,6% respectively.El incremento gradual de la población felina en Colombia y algunos países está acompañado de la aparición de enfermedades que ponen en riesgo la salud animal. El virus de inmunodeficiencia y la leucemia felina son las principales enfermedades retrovirales de mayor morbilidad y mortalidad en los felinos, que requieren de un diagnóstico oportuno que permita prolongar la vida de estos animales. Se realizó un estudio descriptivo de corte transversal que incluyó 60 gatos domésticos del área urbana de la ciudad de Montería procedentes de clínicas, consultorios veterinarios y viviendas familiares. El diagnóstico simultáneo de leucemia e

  2. Antibodies to the core proteins of Nairobi sheep disease virus/Ganjam virus reveal details of the distribution of the proteins in infected cells and tissues.

    Science.gov (United States)

    Lasecka, Lidia; Bin-Tarif, Abdelghani; Bridgen, Anne; Juleff, Nicholas; Waters, Ryan A; Baron, Michael D

    2015-01-01

    Nairobi sheep disease virus (NSDV; also called Ganjam virus in India) is a bunyavirus of the genus Nairovirus. It causes a haemorrhagic gastroenteritis in sheep and goats with mortality up to 90%. The virus is closely related to the human pathogen Crimean-Congo haemorrhagic fever virus (CCHFV). Little is currently known about the biology of NSDV. We have generated specific antibodies against the virus nucleocapsid protein (N) and polymerase (L) and used these to characterise NSDV in infected cells and to study its distribution during infection in a natural host. Due to its large size and the presence of a papain-like protease (the OTU-like domain) it has been suggested that the L protein of nairoviruses undergoes an autoproteolytic cleavage into polymerase and one or more accessory proteins. Specific antibodies which recognise either the N-terminus or the C-terminus of the NSDV L protein showed no evidence of L protein cleavage in NSDV-infected cells. Using the specific anti-N and anti-L antibodies, it was found that these viral proteins do not fully colocalise in infected cells; the N protein accumulated near the Golgi at early stages of infection while the L protein was distributed throughout the cytoplasm, further supporting the multifunctional nature of the L protein. These antibodies also allowed us to gain information about the organs and cell types targeted by the virus in vivo. We could detect NSDV in cryosections prepared from various tissues collected post-mortem from experimentally inoculated animals; the virus was found in the mucosal lining of the small and large intestine, in the lungs, and in mesenteric lymph nodes (MLN), where NSDV appeared to target monocytes and/or macrophages.

  3. Adult T-cell leukemia-associated antigen (ATLA) and anti-ATLA antibodies in patients with Hodgkin's disease in the Nagasaki District.

    Science.gov (United States)

    Kinoshita, K; Amagasaki, T; Yamada, Y; Ikeda, S; Momita, S; Toriya, K; Kamihira, S; Ichimaru, M

    1983-01-01

    Seven patients with Hodgkin's disease in the Nagasaki district were examined for adult T-cell leukemia-associated antigen (ATLA), a human retrovirus-associated antigen, and anti-ATLA antibodies. Anti-ATLA antibody reactivity with the ATLA-positive cultured cells from an ATL patient was demonstrated in four (57.1%) of seven patients. This suggests that infection by a human retrovirus may be closely associated with Hodgkin's disease in the Nagasaki district. However, ATLA could not be induced in the cultured mononuclear cells taken from biopsied lymph nodes of the three patients examined. Hence, it is necessary to collect more direct evidence in the search for a viral etiology of Hodgkin's disease.

  4. cis elements and trans-acting factors involved in dimer formation of murine leukemia virus RNA.

    Science.gov (United States)

    Prats, A C; Roy, C; Wang, P A; Erard, M; Housset, V; Gabus, C; Paoletti, C; Darlix, J L

    1990-02-01

    The genetic material of all retroviruses examined so far consists of two identical RNA molecules joined at their 5' ends by the dimer linkage structure (DLS). Since the precise location of the DLS as well as the mechanism and role(s) of RNA dimerization remain unclear, we analyzed the dimerization process of Moloney murine leukemia virus (MoMuLV) genomic RNA. For this purpose we derived an in vitro model for RNA dimerization. By using this model, murine leukemia virus RNA was shown to form dimeric molecules. Deletion mutagenesis in the 620-nucleotide leader of MoMuLV RNA showed that the dimer promoting sequences are located within the encapsidation element Psi between positions 215 and 420. Furthermore, hybridization assays in which DNA oligomers were used to probe monomer and dimer forms of MoMuLV RNA indicated that the DLS probably maps between positions 280 and 330 from the RNA 5' end. Also, retroviral nucleocapsid protein was shown to catalyze dimerization of MoMuLV RNA and to be tightly bound to genomic dimer RNA in virions. These results suggest that MoMuLV RNA dimerization and encapsidation are probably controlled by the same cis element, Psi, and trans-acting factor, nucleocapsid protein, and thus might be linked during virion formation.

  5. Studies on the antibody response of mice and humans after immunization with potential influenza virus A (H1N1) vaccines

    International Nuclear Information System (INIS)

    Poumbourios, P.; Jackson, D.C.; Oxford, J.S.

    1993-01-01

    The antibody response of mice and adult humans to immunization with subunit vaccines derived from a pair of antigenically distinct influenza A H1N1 viruses isolate in eggs was investigated. Although the haemagglutinin molecule of each virus differed by only three amino acid residues, highly specific antibody responses were elicited in mice as determined by haemagglutination inhibition and radioimmunoprecipitation assays. Results from competitive radioimmunoassays using monoclonal antibodies of known specificity and a study of the reactivity of mouse antisera with H1N1 field strains indicated that the marked differences in the antibody responses to the two vaccines was due to an amino acid substitution in the distal tip of the haemagglutinin molecule. In contrast, cross reactive antibody responses were elicited in humans presumably due to exposure to viruses related to the candidate vaccine prior to vaccination. Although immunogenic differences are apparent in this pair of antigenically distinct viruses in naive laboratory animals, these differences are not apparent following vaccination of humans that had prior exposure to related viruses. 21 refs., 5 tabs., 4 figs

  6. Enhanced CDC of B cell chronic lymphocytic leukemia cells mediated by rituximab combined with a novel anti-complement factor H antibody.

    Directory of Open Access Journals (Sweden)

    Mark T Winkler

    Full Text Available Rituximab therapy for B cell chronic lymphocytic leukemia (B-CLL has met with mixed success. Among several factors to which resistance can be attributed is failure to activate complement dependent cytotoxicity (CDC due to protective complement regulatory proteins, including the soluble regulator complement factor H (CFH. We hypothesized that rituximab killing of non-responsive B-CLL cells could be augmented by a novel human monoclonal antibody against CFH. The B cells from 11 patients with B-CLL were tested ex vivo in CDC assays with combinations of CFH monoclonal antibody, rituximab, and a negative control antibody. CDC of rituximab non-responsive malignant B cells from CLL patients could in some cases be augmented by the CFH monoclonal antibody. Antibody-mediated cytotoxicity of cells was dependent upon functional complement. In one case where B-CLL cells were refractory to CDC by the combination of rituximab plus CFH monoclonal antibody, additionally neutralizing the membrane complement regulatory protein CD59 allowed CDC to occur. Inhibiting CDC regulatory proteins such as CFH holds promise for overcoming resistance to rituximab therapy in B-CLL.

  7. Homology of ab1 and ab3 monoclonal antibodies that neutralize Semliki Forest virus

    NARCIS (Netherlands)

    Fernandez, IM; Bos, NA; Harmsen, M; Verheul, AFM; Snippe, H; Kraaijeveld, CA

    2001-01-01

    A noninternal image monoclonal antiidiotypic antibody (ab2 mAb), designated 1,13A321, that had proved its efficacy as vaccine against infection with Semliki Forest virus (SFV) in BALB/c mice, was used as immunogen to generate a panel of SFV-neutralizing monoclonal anti-anti-idiotypic antibodies (ab3

  8. Seroprevalence of antibodies against chikungunya virus in Singapore resident adult population.

    Science.gov (United States)

    Ang, Li Wei; Kam, Yiu Wing; Lin, Cui; Krishnan, Prabha Unny; Tay, Joanne; Ng, Lee Ching; James, Lyn; Lee, Vernon J M; Goh, Kee Tai; Ng, Lisa F P; Lin, Raymond T P

    2017-12-01

    We determined the seroprevalence of chikungunya virus (CHIKV) infection in the adult resident population in Singapore following local outbreaks of chikungunya fever (CHIKF) in 2008-2009. Our cross-sectional study involved residual sera from 3,293 adults aged 18-79 years who had participated in the National Health Survey in 2010. Sera were tested for IgG antibodies against CHIKV and dengue virus (DENV) and neutralizing antibodies against CHIKV. The prevalence of CHIKV-neutralizing antibodies among Singapore residents aged 18-79 years was 1.9% (95% confidence interval: 1.4%- 2.3%). The CHIKV seroprevalence was highest in the elderly aged 70-79 years at 11.5%, followed by those aged 30-39 years at 3.1%. Men had significantly higher CHIKV seroprevalence than women (2.5% versus 1.3%, p = 0.01). Among the three main ethnic groups, Indians had the highest seroprevalence (3.5%) compared to Chinese (1.6%) and Malays (0.7%) (p = 0.02 and p = 0.01, respectively). Multivariable logistic regression identified adults aged 30-39 years and 70-79 years, men, those of Indian ethnicity and ethnic minority groups, and residence on ground floor of public and private housing apartments as factors that were significantly associated with a higher likelihood of exposure to CHIKV. The overall prevalence of anti-DENV IgG antibodies was 56.8% (95% CI: 55.1%- 58.5%), while 1.5% (95% CI: 1.1%- 2.0%) of adults possessed both neutralizing antibodies against CHIKV and IgG antibodies against DENV. Singapore remains highly susceptible to CHIKV infection. There is a need to maintain a high degree of vigilance through disease surveillance and vector control. Findings from such serological study, when conducted on a regular periodic basis, could supplement surveillance to provide insights on CHIKV circulation in at-risk population.

  9. Neutralizing and non-neutralizing monoclonal antibodies against dengue virus E protein derived from a naturally infected patient

    Directory of Open Access Journals (Sweden)

    Isern Sharon

    2010-02-01

    Full Text Available Abstract Background Antibodies produced in response to infection with any of the four serotypes of dengue virus generally provide homotypic immunity. However, prior infection or circulating maternal antibodies can also mediate a non-protective antibody response that can enhance the course of disease in a subsequent heterotypic infection. Naturally occurring human monoclonal antibodies can help us understand the protective and pathogenic roles of the humoral immune system in dengue virus infection. Results Epstein-Barr Virus (EBV transformation of B cells isolated from the peripheral blood of a human subject with previous dengue infection was performed. B cell cultures were screened by ELISA for antibodies to dengue (DENV envelope (E protein. ELISA positive cultures were cloned by limiting dilution. Three IgG1 human monoclonal antibodies (HMAbs were purified and their binding specificity to E protein was verified by ELISA and biolayer interferometry. Neutralization and enhancement assays were conducted in epithelial and macrophage-like cell lines, respectively. All three HMAbs bound to E from at least two of the four DENV serotypes, one of the HMAbs was neutralizing, and all were able to enhance DENV infection. Conclusions HMAbs against DENV can be successfully generated by EBV transformation of B cells from patients at least two years after naturally acquired DENV infections. These antibodies show different patterns of cross-reactivity, neutralizing, and enhancement activity.

  10. Assay for Serum Antibodies to Infectious Bursal Disease Virus in ...

    African Journals Online (AJOL)

    Infectious bursal disease (IBD) is an acute, lymphocidal disease that has been a threat to poultry production in Nigeria and a major disease problem of poultry producing areas of the world. A serological detection of antibodies to the virus was conducted on 300 sera samples derived from local chickens slaughtered at Sheik ...

  11. Ocelots on Barro Colorado Island are infected with feline immunodeficiency virus but not other common feline and canine viruses.

    Science.gov (United States)

    Franklin, Samuel P; Kays, Roland W; Moreno, Ricardo; TerWee, Julie A; Troyer, Jennifer L; VandeWoude, Sue

    2008-07-01

    Transmission of pathogens from domestic animals to wildlife populations (spill-over) has precipitated local wildlife extinctions in multiple geographic locations. Identifying such events before they cause population declines requires differentiating spillover from endemic disease, a challenge complicated by a lack of baseline data from wildlife populations that are isolated from domestic animals. We tested sera collected from 12 ocelots (Leopardus pardalis) native to Barro Colorado Island, Panama, which is free of domestic animals, for antibodies to feline herpes virus, feline calicivirus, feline corona virus, feline panleukopenia virus, canine distemper virus, and feline immunodeficiency virus (FIV), typically a species-specific infection. Samples also were tested for feline leukemia virus antigens. Positive tests results were only observed for FIV; 50% of the ocelots were positive. We hypothesize that isolation of this population has prevented introduction of pathogens typically attributed to contact with domestic animals. The high density of ocelots on Barro Colorado Island may contribute to a high prevalence of FIV infection, as would be expected with increased contact rates among conspecifics in a geographically restricted population.

  12. Duration of antibody response following vaccination against feline immunodeficiency virus.

    Science.gov (United States)

    Westman, Mark E; Malik, Richard; Hall, Evelyn; Harris, Matthew; Hosie, Margaret J; Norris, Jacqueline M

    2017-10-01

    Objectives Recently, two point-of-care (PoC) feline immunodeficiency virus (FIV) antibody test kits (Witness and Anigen Rapid) were reported as being able to differentiate FIV-vaccinated from FIV-infected cats at a single time point, irrespective of the gap between testing and last vaccination (0-7 years). The aim of the current study was to investigate systematically anti-FIV antibody production over time in response to the recommended primary FIV vaccination series. Methods First, residual plasma from the original study was tested using a laboratory-based ELISA to determine whether negative results with PoC testing were due to reduced as opposed to absent antibodies to gp40. Second, a prospective study was performed using immunologically naive client-owned kittens and cats given a primary FIV vaccination series using a commercially available inactivated whole cell/inactivated whole virus vaccine (Fel-O-Vax FIV, three subcutaneous injections at 4 week intervals) and tested systematically (up to 11 times) over 6 months, using four commercially available PoC FIV antibody kits (SNAP FIV/FeLV Combo [detects antibodies to p15/p24], Witness FeLV/FIV [gp40], Anigen Rapid FIV/FeLV [p24/gp40] and VetScan FeLV/FIV Rapid [p24]). Results The laboratory-based ELISA showed cats from the original study vaccinated within the previous 0-15 months had detectable levels of antibodies to gp40, despite testing negative with two kits that use gp40 as a capture antigen (Witness and Anigen Rapid kits). The prospective study showed that antibody testing with SNAP Combo and VetScan Rapid was positive in all cats 2 weeks after the second primary FIV vaccination, and remained positive for the duration of the study (12/12 and 10/12 cats positive, respectively). Antibody testing with Witness and Anigen Rapid was also positive in a high proportion of cats 2 weeks after the second primary FIV vaccination (8/12 and 7/12, respectively), but antibody levels declined below the level of detection in

  13. Radioimmunodetection of human leukemia with anti-interleukin-2 receptor antibody in severe combined immunodeficiency mice

    International Nuclear Information System (INIS)

    Hosono, Makoto; Takaori-Kondo, Akifumi; Zheng-Sheng, Yao; Kobayashi, Hisataka; Hosono, Masako N.; Sakahara, Harumi; Imada, Kazunori; Okuma, Minoru; Uchiyama, Takashi; Konishi, Junji

    1995-01-01

    Anti-Tac monoclonal antibody recognizes human interleukin-2 receptor, which is overexpressed in leukemic cells of most adult T-cell leukemia (ATL) patients. To examine the potency of anti-Tac for targeting of ATL, biodistributions of intravenously administered 125 I- and 111 In-labeled anti-Tac were examined in severe combined immunodeficiency (SCID) mice inoculated with ATL cells. Significant amounts of radiolabeled anti-Tac were found in the spleen and thymus. The trafficking of ATL cells in SCID mice was detected using 111 In-oxine-labeled ATL cells. These results were coincident with the histologically confirmed infiltration of ATL cells. The radiolabeled anti-Tac seemed potent for targeting of ATL

  14. Noninfectious virus-like particles produced by Moloney murine leukemia virus-based retrovirus packaging cells deficient in viral envelope become infectious in the presence of lipofection reagents

    Science.gov (United States)

    Sharma, Sanjai; Murai, Fukashi; Miyanohara, Atsushi; Friedmann, Theodore

    1997-01-01

    Retrovirus packaging cell lines expressing the Moloney murine leukemia virus gag and pol genes but lacking virus envelope genes produce virus-like particles constitutively, whether or not they express a transcript from an integrated retroviral provirus. In the absence of a proviral transcript, the assembled particles contain processed gag and reverse transcriptase, and particles made by cells expressing an integrated lacZ provirus also contain viral RNA. The virus-like particles from both cell types are enveloped and are secreted/budded into the extracellular space but are noninfectious. Their physicochemical properties are similar to those of mature retroviral particles. The noninfectious gag pol RNA particles can readily be made infectious by the addition of lipofection reagents to produce preparations with titers of up to 105 colony-forming units per ml. PMID:9380714

  15. Noninfectious virus-like particles produced by Moloney murine leukemia virus-based retrovirus packaging cells deficient in viral envelope become infectious in the presence of lipofection reagents.

    Science.gov (United States)

    Sharma, S; Murai, F; Miyanohara, A; Friedmann, T

    1997-09-30

    Retrovirus packaging cell lines expressing the Moloney murine leukemia virus gag and pol genes but lacking virus envelope genes produce virus-like particles constitutively, whether or not they express a transcript from an integrated retroviral provirus. In the absence of a proviral transcript, the assembled particles contain processed gag and reverse transcriptase, and particles made by cells expressing an integrated lacZ provirus also contain viral RNA. The virus-like particles from both cell types are enveloped and are secreted/budded into the extracellular space but are noninfectious. Their physicochemical properties are similar to those of mature retroviral particles. The noninfectious gag pol RNA particles can readily be made infectious by the addition of lipofection reagents to produce preparations with titers of up to 10(5) colony-forming units per ml.

  16. Survey for West Nile virus antibodies in wild ducks, 2004-06, USA

    Science.gov (United States)

    Hofmeister, Erik K.; Jankowski, Mark D.; Goldberg, Diana R.; Franson, J. Christian

    2016-01-01

    Detection of West Nile virus (WNV) in ducks has been reported in North America in isolated cases of mortality in wild waterbirds and following outbreaks in farmed ducks. Although the virus has been noted as an apparent incidental finding in several species of ducks, little is known about the prevalence of exposure or the outcome of infection with WNV in wild ducks in North America. From 2004–06, we collected sera from 1,406 wild-caught American Wigeon (Anas americana), Mallard (Anas platyrhynchos), and Northern Pintail (Anas acuta) ducks at national wildlife refuges (NWRs) in North Dakota and Wood Ducks (Aix sponsa) at NWRs in South Carolina and Tennessee. We measured the prevalence of previous exposure to WNV in these ducks by measuring WNV antibodies and evaluated variation in exposure among species, age, and year. Additionally, we evaluated the performance of a commercial antibody to wild bird immunoglobulin in duck species that varied in their phylogenetic relatedness to the bird species the antibody was directed against. As determined by a screening immunoassay and a confirmatory plaque reduction neutralization assay, the prevalence of WNV antibody was 10%. In light of experimental studies that show ducks to be relatively resistant to mortality caused by WNV, the antibody prevalence we detected suggests that wild ducks may be less-frequently exposed to WNV than expected for birds inhabiting wetlands where they may acquire infection from mosquitoes.

  17. Generation, characterization and epitope mapping of two neutralizing and protective human recombinant antibodies against influenza A H5N1 viruses.

    Directory of Open Access Journals (Sweden)

    Lina Sun

    Full Text Available BACKGROUND: The development of new therapeutic targets and strategies to control highly pathogenic avian influenza (HPAI H5N1 virus infection in humans is urgently needed. Broadly cross-neutralizing recombinant human antibodies obtained from the survivors of H5N1 avian influenza provide an important role in immunotherapy for human H5N1 virus infection and definition of the critical epitopes for vaccine development. METHODOLOGY/PRINCIPAL FINDINGS: We have characterized two recombinant baculovirus-expressed human antibodies (rhAbs, AVFluIgG01 and AVFluIgG03, generated by screening a Fab antibody phage library derived from a patient recovered from infection with a highly pathogenic avian influenza A H5N1 clade 2.3 virus. AVFluIgG01 cross-neutralized the most of clade 0, clade 1, and clade 2 viruses tested, in contrast, AVFluIgG03 only neutralized clade 2 viruses. Passive immunization of mice with either AVFluIgG01 or AVFluIgG03 antibody resulted in protection from a lethal H5N1 clade 2.3 virus infection. Furthermore, through epitope mapping, we identify two distinct epitopes on H5 HA molecule recognized by these rhAbs and demonstrate their potential to protect against a lethal H5N1 virus infection in a mouse model. CONCLUSIONS/SIGNIFICANCE: Importantly, localization of the epitopes recognized by these two neutralizing and protective antibodies has provided, for the first time, insight into the human antibody responses to H5N1 viruses which contribute to the H5 immunity in the recovered patient. These results highlight the potential of a rhAbs treatment strategy for human H5N1 virus infection and provide new insight for the development of effective H5N1 pandemic vaccines.

  18. Stoichiometry of monoclonal antibody neutralization of T-cell line-adapted human immunodeficiency virus type 1

    DEFF Research Database (Denmark)

    Schønning, Kristian; Lund, O; Lund, O S

    1999-01-01

    In order to study the stoichiometry of monoclonal antibody (MAb) neutralization of T-cell line-adapted human immunodeficiency virus type 1 (HIV-1) in antibody excess and under equilibrium conditions, we exploited the ability of HIV-1 to generate mixed oligomers when different env genes...

  19. Vaccine-induced antibodies to herpes simplex virus glycoprotein D epitopes involved in virus entry and cell-to-cell spread correlate with protection against genital disease in guinea pigs.

    Science.gov (United States)

    Hook, Lauren M; Cairns, Tina M; Awasthi, Sita; Brooks, Benjamin D; Ditto, Noah T; Eisenberg, Roselyn J; Cohen, Gary H; Friedman, Harvey M

    2018-05-01

    Herpes simplex virus type 2 (HSV-2) glycoprotein D (gD2) subunit antigen is included in many preclinical candidate vaccines. The rationale for including gD2 is to produce antibodies that block crucial gD2 epitopes involved in virus entry and cell-to-cell spread. HSV-2 gD2 was the only antigen in the Herpevac Trial for Women that protected against HSV-1 genital infection but not HSV-2. In that trial, a correlation was detected between gD2 ELISA titers and protection against HSV-1, supporting the importance of antibodies. A possible explanation for the lack of protection against HSV-2 was that HSV-2 neutralization titers were low, four-fold lower than to HSV-1. Here, we evaluated neutralization titers and epitope-specific antibody responses to crucial gD2 epitopes involved in virus entry and cell-to-cell spread as correlates of immune protection against genital lesions in immunized guinea pigs. We detected a strong correlation between neutralizing antibodies and protection against genital disease. We used a high throughput biosensor competition assay to measure epitope-specific responses to seven crucial gD2 linear and conformational epitopes involved in virus entry and spread. Some animals produced antibodies to most crucial epitopes while others produced antibodies to few. The number of epitopes recognized by guinea pig immune serum correlated with protection against genital lesions. We confirmed the importance of antibodies to each crucial epitope using monoclonal antibody passive transfer that improved survival and reduced genital disease in mice after HSV-2 genital challenge. We re-evaluated our prior study of epitope-specific antibody responses in women in the Herpevac Trial. Humans produced antibodies that blocked significantly fewer crucial gD2 epitopes than guinea pigs, and antibody responses in humans to some linear epitopes were virtually absent. Neutralizing antibody titers and epitope-specific antibody responses are important immune parameters to

  20. Safety and efficacy of ofatumumab, a fully human monoclonal anti-CD20 antibody, in patients with relapsed or refractory B-cell chronic lymphocytic leukemia

    DEFF Research Database (Denmark)

    Coiffier, Bertrand; Lepretre, Stéphane; Pedersen, Lars Møller

    2008-01-01

    Safety and efficacy of the fully human anti-CD20 monoclonal antibody, ofatumumab, was analyzed in a multicenter dose-escalating study including 33 patients with relapsed or refractory chronic lymphocytic leukemia. Three cohorts of 3 (A), 3 (B), and 27 (C) patients received 4, once weekly, infusio...

  1. Antibodies to the core proteins of Nairobi sheep disease virus/Ganjam virus reveal details of the distribution of the proteins in infected cells and tissues.

    Directory of Open Access Journals (Sweden)

    Lidia Lasecka

    Full Text Available Nairobi sheep disease virus (NSDV; also called Ganjam virus in India is a bunyavirus of the genus Nairovirus. It causes a haemorrhagic gastroenteritis in sheep and goats with mortality up to 90%. The virus is closely related to the human pathogen Crimean-Congo haemorrhagic fever virus (CCHFV. Little is currently known about the biology of NSDV. We have generated specific antibodies against the virus nucleocapsid protein (N and polymerase (L and used these to characterise NSDV in infected cells and to study its distribution during infection in a natural host. Due to its large size and the presence of a papain-like protease (the OTU-like domain it has been suggested that the L protein of nairoviruses undergoes an autoproteolytic cleavage into polymerase and one or more accessory proteins. Specific antibodies which recognise either the N-terminus or the C-terminus of the NSDV L protein showed no evidence of L protein cleavage in NSDV-infected cells. Using the specific anti-N and anti-L antibodies, it was found that these viral proteins do not fully colocalise in infected cells; the N protein accumulated near the Golgi at early stages of infection while the L protein was distributed throughout the cytoplasm, further supporting the multifunctional nature of the L protein. These antibodies also allowed us to gain information about the organs and cell types targeted by the virus in vivo. We could detect NSDV in cryosections prepared from various tissues collected post-mortem from experimentally inoculated animals; the virus was found in the mucosal lining of the small and large intestine, in the lungs, and in mesenteric lymph nodes (MLN, where NSDV appeared to target monocytes and/or macrophages.

  2. Human antibody technology and the development of antibodies against cytomegalovirus.

    Science.gov (United States)

    Ohlin, Mats; Söderberg-Nauclér, Cecilia

    2015-10-01

    Cytomegalovirus (CMV) is a virus that causes chronic infections in a large set of the population. It may cause severe disease in immunocompromised individuals, is linked to immunosenescence and implied to play an important role in the pathogenesis of cardiovascular diseases and cancer. Modulation of the immune system's abilities to manage the virus represent a highly viable therapeutic option and passive immunotherapy with polyclonal antibody preparations is already in clinical use. Defined monoclonal antibodies offer many advantages over polyclonal antibodies purified from serum. Human CMV-specific monoclonal antibodies have consequently been thoroughly investigated with respect to their potential in the treatment of diseases caused by CMV. Recent advances in human antibody technology have substantially expanded the breadth of antibodies for such applications. This review summarizes the fundamental basis for treating CMV disease by use of antibodies, the basic technologies to be used to develop such antibodies, and relevant human antibody specificities available to target this virus. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Influenza A virus H5-specific antibodies in mute swans (Cygnus olor) in the USA.

    Science.gov (United States)

    Kistler, Whitney M; Stallknecht, David E; Lebarbenchon, Camille; Pedersen, Kerri; Marks, David R; Mickley, Randy; DeLiberto, Thomas J; Yabsley, Michael J

    2015-04-01

    The use of serologic assays for influenza A virus (IAV) surveillance in wild birds has increased because of the availability of commercial enzyme-linked immunosorbent assays (ELISAs). Recently, an H5-specific blocking ELISA (bELISA) was shown to reliably detect H5-specific antibodies to low- and high-pathogenic H5 viruses in experimentally infected waterfowl. Mute Swans (Cygnus olor) were frequently associated with highly pathogenic H5N1 outbreaks in Europe and may have a similar role if highly pathogenic H5N1 is introduced into North America. We measured the prevalence of antibodies to the nucleoprotein and H5 protein in Mute Swans using three serologic assays. We collected 340 serum samples from Mute Swans in Michigan, New Jersey, New York, and Rhode Island, US. We detected antibodies to the IAV nucleoprotein in 66.2% (225/340) of the samples. We detected H5-specific antibodies in 62.9% (214/340) and 18.8% (64/340) using a modified H5 bELISA protocol and hemagglutination inhibition (HI) assay, respectively. The modified H5 bELISA protocol detected significantly more positive samples than did the manufacturer's protocol. We also tested 46 samples using virus neutralization. Neutralization results had high agreement with the modified H5 bELISA protocol and detected a higher prevalence than did the HI assay. These results indicate that North American Mute Swans have high nucleoprotein and H5 antibody prevalences.

  4. Screening for antibodies against Aleutian disease virus (ADV) in mink. Elucidation of dubious results by additive counterimmunoelectrophoresis

    DEFF Research Database (Denmark)

    Uttenthal, Åse

    1992-01-01

    In order to distinguish true positive results in counterimmunoelectrophoresis from false positive ones an additive counterimmunoelectrophoresis was developed. The method was tested on selected mink serum samples as part of a routine testing for antibodies towards Aleutian disease virus on 3 million...... blood samples. The procedure of the method is, that a known positive serum sample is mixed with the patient serum to be tested. The result from a false positive sample will be one precipitin line towards virus and one nonspecific line. If the serum sample is a true positive one, the antibodies...... originating from the patient serum will be added to the antibodies in the standard positive serum giving only one precipitin line. The system is further extended by testing the serum samples towards an antigen preparation containing all the cellular components but free from virus....

  5. Notch2 transduction by feline leukemia virus in a naturally infected cat.

    Science.gov (United States)

    Watanabe, Shinya; Ito, Jumpei; Baba, Takuya; Hiratsuka, Takahiro; Kuse, Kyohei; Ochi, Haruyo; Anai, Yukari; Hisasue, Masaharu; Tsujimoto, Hajime; Nishigaki, Kazuo

    2014-04-01

    Feline leukemia virus (FeLV) induces neoplastic and nonneoplastic diseases in cats. The transduction of cellular genes by FeLV is sometimes observed and associated with neoplastic diseases including lymphoma and sarcoma. Here, we report the first natural case of feline Notch2 transduction by FeLV in an infected cat with multicentric lymphoma and hypercalcemia. We cloned recombinant FeLVs harboring Notch2 in the env gene. Notch2 was able to activate expression of a reporter gene, similar to what was previously reported in cats with experimental FeLV-induced thymic lymphoma. Our findings suggest that the transduction of Notch2 strongly correlates with FeLV-induced lymphoma.

  6. Terminal deoxynucleotidyl transferase in the diagnosis of leukemia and malignant lymphoma.

    Science.gov (United States)

    Kung, P C; Long, J C; McCaffrey, R P; Ratliff, R L; Harrison, T A; Baltimore, D

    1978-05-01

    Neoplastic cells from 253 patients with leukemia and 46 patients with malignant lymphoma were studied for the presence of terminal deoxynucleotidyl transferase (TdT) by biochemical and fluorescent antibody technics. TdT was detected in circulating blast cells from 73 of 77 patients with acute lymphoblastic leukemia, 24 of 72 patients with chronic myelogenous leukemia examined during the blastic phase of the disorder and in cell suspensions of lymph nodes from nine of nine patients with diffuse lymphoblastic lymphoma. Blast cells from six of 10 patients with acute undifferentiated leukemia were TdT positive, but the enzyme was found in only two of 55 patients with acute myeloblastic leukemia. TdT was not detected in other lymphocytic or granulocytic leukemias or in other types of malignant lymphomas. The fluorescent antibody assay for TdT permits rapid and specific identification of the enzyme in single cells. The TdT assay is clinically useful in confirming the diagnosis of acute lymphoblastic leukemia, evaluating patients with blastic chronic myelogenous leukemia, and distinguishing patients with lymphoblastic lymphoma, whose natural history includes rapid extranodal dissemination, from patients with other poorly differentiated malignant lymphomas.

  7. Bovine respiratory syncytial virus ISCOMs - protection in the presence of maternal antibodies

    DEFF Research Database (Denmark)

    Hägglund, Sara; Hu, Ke-Fei; Larsen, Lars Erik

    2004-01-01

    The protection induced by immunostimulating complexes (ISCOMs) against bovine respiratory syncytial virus (BRSV) was evaluated and compared to that of a commercial inactivated vaccine (CV) in calves with BRSV-specific maternal antibodies. Following experimental challenge, controls (n = 4...

  8. Murine leukemia virus (MLV replication monitored with fluorescent proteins

    Directory of Open Access Journals (Sweden)

    Bittner Alexandra

    2004-12-01

    Full Text Available Abstract Background Cancer gene therapy will benefit from vectors that are able to replicate in tumor tissue and cause a bystander effect. Replication-competent murine leukemia virus (MLV has been described to have potential as cancer therapeutics, however, MLV infection does not cause a cytopathic effect in the infected cell and viral replication can only be studied by immunostaining or measurement of reverse transcriptase activity. Results We inserted the coding sequences for green fluorescent protein (GFP into the proline-rich region (PRR of the ecotropic envelope protein (Env and were able to fluorescently label MLV. This allowed us to directly monitor viral replication and attachment to target cells by flow cytometry. We used this method to study viral replication of recombinant MLVs and split viral genomes, which were generated by replacement of the MLV env gene with the red fluorescent protein (RFP and separately cloning GFP-Env into a retroviral vector. Co-transfection of both plasmids into target cells resulted in the generation of semi-replicative vectors, and the two color labeling allowed to determine the distribution of the individual genomes in the target cells and was indicative for the occurrence of recombination events. Conclusions Fluorescently labeled MLVs are excellent tools for the study of factors that influence viral replication and can be used to optimize MLV-based replication-competent viruses or vectors for gene therapy.

  9. Radioimmunoassay of antibody e against hepatitis-B virus (HBeAb, anti-HBe)

    International Nuclear Information System (INIS)

    Kselikova, M.; Novak, J.; Urbankova, J.

    1981-01-01

    The Abbott-HBe kit renders possible a radioimmunoassay of antibody e against antigen e of the hepatitis-B virus. This detection proceeds in 2 phases: the higher the antibody-e titer in the examined serum the lower the number of pulses measured. HBeAb occurred in 87 test persons. The antibody was most frequently detected in symptom-free carriers of the surface antigen (80%), furthermore in the medical staff of the departments of infectious hepatitides (39%), in hospitalized patients with infectious hepatitis (36%), and in employees of the first-aid service (25%). In blood donors as control group HBeAb was not detected. (author)

  10. A radiolabeled antibody targeting CD123+ leukemia stem cells – initial radioimmunotherapy studies in NOD/SCID mice engrafted with primary human AML

    Directory of Open Access Journals (Sweden)

    Jeffrey V. Leyton

    2015-01-01

    Full Text Available Radioimmunotherapy (RIT with anti-CD123 monoclonal antibody CSL360 modified with nuclear translocation sequence (NLS peptides and labeled with the Auger electron-emitter, 111In (111In-NLS-CSL360 was studied in the prevalent NOD/SCID mouse AML engraftment assay. Significant decreases in CD123+ leukemic cells and impairment of leukemic stem cell self-renewal were achieved with high doses of RIT. However, NOD/SCID mice were very radiosensitive to these doses. At low non-toxic treatment doses, 111In-NLS-CSL360 demonstrated a trend towards improved survival associated with decreased spleen/body weight ratio, an indicator of leukemia burden, and almost complete eradication of leukemia from the bone marrow in some mice.

  11. A neutralizing human monoclonal antibody protects against lethal disease in a new ferret model of acute nipah virus infection.

    Directory of Open Access Journals (Sweden)

    Katharine N Bossart

    2009-10-01

    Full Text Available Nipah virus is a broadly tropic and highly pathogenic zoonotic paramyxovirus in the genus Henipavirus whose natural reservoirs are several species of Pteropus fruit bats. Nipah virus has repeatedly caused outbreaks over the past decade associated with a severe and often fatal disease in humans and animals. Here, a new ferret model of Nipah virus pathogenesis is described where both respiratory and neurological disease are present in infected animals. Severe disease occurs with viral doses as low as 500 TCID(50 within 6 to 10 days following infection. The underlying pathology seen in the ferret closely resembles that seen in Nipah virus infected humans, characterized as a widespread multisystemic vasculitis, with virus replicating in highly vascular tissues including lung, spleen and brain, with recoverable virus from a variety of tissues. Using this ferret model a cross-reactive neutralizing human monoclonal antibody, m102.4, targeting the henipavirus G glycoprotein was evaluated in vivo as a potential therapeutic agent. All ferrets that received m102.4 ten hours following a high dose oral-nasal Nipah virus challenge were protected from disease while all controls died. This study is the first successful post-exposure passive antibody therapy for Nipah virus using a human monoclonal antibody.

  12. CANINE DISTEMPER VIRUS ANTIBODY TITERS IN DOMESTIC CATS AFTER DELIVERY OF A LIVE ATTENUATED VIRUS VACCINE.

    Science.gov (United States)

    Ramsay, Edward; Sadler, Ryan; Rush, Robert; Seimon, Tracie; Tomaszewicz, Ania; Fleetwood, Ellen A; McAloose, Denise; Wilkes, Rebecca P

    2016-06-01

    Three methods for delivering a live attenuated canine distemper virus (CDV) vaccine to domestic cats ( Felis catus ) were investigated, as models for developing vaccination protocols for tigers (Panthera tigris). Twenty domestic cats were randomly divided into four treatment groups: saline injection (negative controls); and oral, intranasal, and subcutaneous vaccinates. Cats were injected with saline or a CDV vaccine (Nobivac DP, Merck) at wk 0 and 4. Blood and nasal swabs were collected at wk 0 (prior to the initial vaccination) and weekly thereafter for 9 wk. Urine samples were collected on wk 1 to 9 after initial vaccination. Forty-nine weeks following the initial vaccination series, three cats from the subcutaneous group and three cats from the intranasal group were revaccinated. Blood was collected immediately prior, and 7 and 21 days subsequent to revaccination. Nasal swabs and urine samples were collected from each cat prior to wk 49 revaccination and daily for 7 days thereafter. Nasal swabs and urine were analyzed by quantitative PCR for vaccine virus presence. Sera were tested for CDV antibodies by virus neutralization. All cats were sero-negative for CDV antibodies at the beginning of the study, and saline-injected cats remained sero-negative throughout the study. A dramatic anamnestic response was seen following wk 4 subcutaneous vaccinations, with titers peaking at wk 6 (geometric mean = 2,435.5). Following wk 49 revaccination, subcutaneous vaccinates again mounted impressive titers (wk 52 geometric mean = 2,048). Revaccination of the intranasal group cats at wk 49 produced a small increase in titers (wk 52 geometric mean = 203). CDV viral RNA was detected in six nasal swabs but no urine samples, demonstrating low viral shedding postvaccination. The strong antibody response to subcutaneous vaccination and the lack of adverse effects suggest this vaccine is safe and potentially protective against CDV infection in domestic cats.

  13. Leukemia-associated antigens in man.

    Science.gov (United States)

    Brown, G; Capellaro, D; Greaves, M

    1975-12-01

    Rabbit antisera raised against acute lymphoblastic leukemia (ALL) cells were used to distinguish ALL from other leukemias, to identify rare leukemia cells in the bone marrow of patients in remission, and to define human leukemia-associated antigens. Antibody binding was studied with the use of immunofluorescence reagents and the analytic capacity of the Fluorescence Activated Cell Sorter-1 (FACS-1). The results indicated that most non-T-cell ALL have three leukemia-associated antigens on their surface which are absent from normal lymphoid cells: 1) an antigen shared with myelocytes, myeloblastic leukemia cells, and fetal liver (hematopoietic) cells; 2) an antigen shared with a subset of intermediate normoblasts in normal bone marrow and fetal liver; and 3) an antigen found thus far only on non-T-cell ALL and in some acute undifferentiated leukemias, which we therefore regard as a strong candidate for a leukemia-specific antigen. These antigens are absent from a subgroup of ALL patients in which the lymphoblasta express T-cell surface markers. Preliminary studies on the bone marrow samples of patients in remission indicated that rare leukemia cells were present in some samples. The implications of these findings with respect to the heterogeneity and cell origin(s) of ALL, its diagnosis, and its potential monitoring during treatment were discussed.

  14. Applying antibody-sensitive hypervariable region 1-deleted hepatitis C virus to the study of escape pathways of neutralizing human monoclonal antibody AR5A

    DEFF Research Database (Denmark)

    Velazquez-Moctezuma, Rodrigo; Law, Mansun; Bukh, Jens

    2017-01-01

    Hepatitis C virus (HCV) is a major cause of end-stage liver diseases. With 3–4 million new HCV infections yearly, a vaccine is urgently needed. A better understanding of virus escape from neutralizing antibodies and their corresponding epitopes are important for this effort. However, for viral is...

  15. Molecular detection of Bluetongue Virus (BTV and Bovine Leukemia Virus (BLV in uterine biopsies of dairy cows with or without reproductive problems

    Directory of Open Access Journals (Sweden)

    Juliana Marques Bicalho

    2016-10-01

    Full Text Available Reproductive performance of dairy cows has a direct impact on herd productivity. Infectious agents, such as Bluetongue Virus (BTV and Bovine Leukemia Virus (BLV, are associated with reproductive failure. However, it remains unknown if these viruses are present in the uterus and cause gestational loss. This study used molecular methods to assess if BTV and BLV can be detected in the uterus of serologically positive dairy cows with a record of abortions, stillbirths and repeat breeding (n=23 and without a record of reproductive problems (n =23. The cows came from three dairy herds of the state of Minas Gerais, Brazil. BTV was not detected in any of the uterine biopsies. Proviral DNA of BLV was detected in 54.5 % of the seropositive cows, but positivity for BLV in the uterus was not associated with the existence of reproductive problems. In conclusion, this study shows that BLV, but not BTV, is present in the uterus of seropositive cows, regardless of reproductive performance.

  16. Serotype Specificity of Antibodies against Foot-and-Mouth Disease Virus in Cattle in Selected Districts in Uganda

    DEFF Research Database (Denmark)

    Mwiine, F.N.; Ayebazibwe, C.; Olaho-Mukani, W.

    2010-01-01

    Uganda had an unusually large number of foot-and-mouth disease (FMD) outbreaks in 2006, and all clinical reports were in cattle. A serological investigation was carried out to confirm circulating antibodies against foot-and-mouth disease virus (FMDV) by ELISA for antibodies against non-structural......Uganda had an unusually large number of foot-and-mouth disease (FMD) outbreaks in 2006, and all clinical reports were in cattle. A serological investigation was carried out to confirm circulating antibodies against foot-and-mouth disease virus (FMDV) by ELISA for antibodies against non......-structural proteins and structural proteins. Three hundred and forty-nine cattle sera were collected from seven districts in Uganda, and 65% of these were found positive for antibodies against the non-structural proteins of FMDV. A subset of these samples were analysed for serotype specificity of the identified...... antibodies. High prevalences of antibodies against non-structural proteins and structural proteins of FMDV serotype O were demonstrated in herds with typical visible clinical signs of FMD, while prevalences were low in herds without clinical signs of FMD. Antibody titres were higher against serotype O than...

  17. Molecular determinants of dengue virus 2 envelope protein important for virus entry in FcγRIIA-mediated antibody-dependent enhancement of infection

    International Nuclear Information System (INIS)

    Chotiwan, Nunya; Roehrig, John T.; Schlesinger, Jacob J.; Blair, Carol D.; Huang, Claire Y.-H.

    2014-01-01

    Antibody-dependent enhancement (ADE) of infection may cause severe illness in patients suffering a secondary infection by a heterologous dengue virus (DENV) serotype. During ADE of infection, cross-reactive non- or poorly-neutralizing antibodies form infectious virus-Ab complexes with the newly infecting serotype and enhance virus infection by binding to the Fcγ receptors (FcγR) on FcγR-bearing cells. In this study, we determined that molecular determinants of DENV2 envelope protein critical for virus entry during non-ADE infection are also required for ADE infection mediated by FcγRIIA, and binding of virus-Ab complexes with FcγRIIA alone is not sufficient for ADE of infection. The FcγRIIA mainly plays an auxiliary role in concentrating the virus–Ab complex to the cell surface, and other primary cellular receptors are required for virus entry. Understanding the viral entry pathway in ADE of DENV infection will greatly facilitate rational designs of anti-viral therapeutics against severe dengue disease associated with ADE. - Highlights: • KKK305/307/310 in DENV2 E-DIII is critical for virus attachment in ADE and non-ADE infection. • Binding of DENV2–Ab complex with FcγRII alone is not sufficient for virus entry in ADE infection. • Other primary receptors were required for DENV2 internalization during FcγRII–mediated ADE. • G104 and L135 of DENV2 E are critical for virus-mediated membrane fusion. • DENV2 virus-mediated membrane fusion is required for both ADE and non-ADE infection

  18. Molecular determinants of dengue virus 2 envelope protein important for virus entry in FcγRIIA-mediated antibody-dependent enhancement of infection

    Energy Technology Data Exchange (ETDEWEB)

    Chotiwan, Nunya; Roehrig, John T. [Arboviral Diseases Branch, Division of Vector-Borne Disease, Centers for Disease Control and Prevention, Fort Collins, CO 80521 (United States); Schlesinger, Jacob J. [Department of Medicine, University of Rochester, Rochester, NY 14642 (United States); Blair, Carol D. [Arthropod-borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523 (United States); Huang, Claire Y.-H., E-mail: yxh0@cdc.gov [Arboviral Diseases Branch, Division of Vector-Borne Disease, Centers for Disease Control and Prevention, Fort Collins, CO 80521 (United States)

    2014-05-15

    Antibody-dependent enhancement (ADE) of infection may cause severe illness in patients suffering a secondary infection by a heterologous dengue virus (DENV) serotype. During ADE of infection, cross-reactive non- or poorly-neutralizing antibodies form infectious virus-Ab complexes with the newly infecting serotype and enhance virus infection by binding to the Fcγ receptors (FcγR) on FcγR-bearing cells. In this study, we determined that molecular determinants of DENV2 envelope protein critical for virus entry during non-ADE infection are also required for ADE infection mediated by FcγRIIA, and binding of virus-Ab complexes with FcγRIIA alone is not sufficient for ADE of infection. The FcγRIIA mainly plays an auxiliary role in concentrating the virus–Ab complex to the cell surface, and other primary cellular receptors are required for virus entry. Understanding the viral entry pathway in ADE of DENV infection will greatly facilitate rational designs of anti-viral therapeutics against severe dengue disease associated with ADE. - Highlights: • KKK305/307/310 in DENV2 E-DIII is critical for virus attachment in ADE and non-ADE infection. • Binding of DENV2–Ab complex with FcγRII alone is not sufficient for virus entry in ADE infection. • Other primary receptors were required for DENV2 internalization during FcγRII–mediated ADE. • G104 and L135 of DENV2 E are critical for virus-mediated membrane fusion. • DENV2 virus-mediated membrane fusion is required for both ADE and non-ADE infection.

  19. Fcγ-receptor IIa-mediated Src Signaling Pathway Is Essential for the Antibody-Dependent Enhancement of Ebola Virus Infection.

    Directory of Open Access Journals (Sweden)

    Wakako Furuyama

    2016-12-01

    Full Text Available Antibody-dependent enhancement (ADE of Ebola virus (EBOV infection has been demonstrated in vitro, raising concerns about the detrimental potential of some anti-EBOV antibodies. ADE has been described for many viruses and mostly depends on the cross-linking of virus-antibody complexes to cell surface Fc receptors, leading to enhanced infection. However, little is known about the molecular mechanisms underlying this phenomenon. Here we show that Fcγ-receptor IIa (FcγRIIa-mediated intracellular signaling through Src family protein tyrosine kinases (PTKs is required for ADE of EBOV infection. We found that deletion of the FcγRIIa cytoplasmic tail abolished EBOV ADE due to decreased virus uptake into cellular endosomes. Furthermore, EBOV ADE, but not non-ADE infection, was significantly reduced by inhibition of the Src family protein PTK pathway, which was also found to be important to promote phagocytosis/macropinocytosis for viral uptake into endosomes. We further confirmed a significant increase of the Src phosphorylation mediated by ADE. These data suggest that antibody-EBOV complexes bound to the cell surface FcγRIIa activate the Src signaling pathway that leads to enhanced viral entry into cells, providing a novel perspective for the general understanding of ADE of virus infection.

  20. Prodduction of clone secretor of antibodies (IgG againt of infection bursal disease virus

    Directory of Open Access Journals (Sweden)

    Sandra Yuliet Marín

    2015-06-01

    Full Text Available ABSTRACT. Marín S.Y., dos Santos B.M., Patarroyo J.H. & Vargas M.I. [Prodduction of clone secretor of antibodies (IgG againt of infection bursal disease virus.] Produção de clones secretores de anticorpos (IgG contra o vírus da doença infecciosa bursal. Revista Brasileira de Medicina Veterinária, 37(2:238-144, 2015. Programa de Pós-Graduação em Medicina Veterinária, Universidade Federal de Viçosa, Avenida PH Rolfs, s/n, Viçosa, MG 36570- 000, Brasil. E-mail: bmsantos@ufv.br Three clones secreting of antibodies (Abs IgG against infection bursal disease virus IBDV was development. The IBDV was strain S706 (the intermediate vaccine was replicated in VERO cell and purified by sucrose gradient, for ELISA and mice inoculation. For the immunization of the mice BALB/c using as a saponin adjuvant, that allowed an inflammation reaction which enhanced the antibody response, detectable by ELISA. The fusion of splenic cells of the immunized mice and the mieloma SP2/0 resulted in 2 hybridoma families (2H11 and 5C7. After cloning by limiting dilution, 3 clones secretors of Abs from IgG class were obtained. The 3 obtained Abs were capable to reveal the proteins turn VPX and VP2 by “western blotting”, respectively of 47 kDa and 41 kDa. The definition of the isotypes recognized by obtained Abs must be object of characterization to allow the use of the antibodies in immunodiagnostic tests such as immunofluorescence, immunocitochemistry or capture ELISA, for epidemiologic of the disease researches or to differentiate vaccine’s virus of the field virus.

  1. New hematological key for bovine leukemia virus-infected Japanese Black cattle.

    Science.gov (United States)

    Mekata, Hirohisa; Yamamoto, Mari; Kirino, Yumi; Sekiguchi, Satoshi; Konnai, Satoru; Horii, Yoichiro; Norimine, Junzo

    2018-02-20

    The European Community's (EC) Key, which is also called Bendixen's Key, is a well-established bovine leukemia virus (BLV) diagnostic method that classifies cattle according to the absolute lymphocyte count and age. The EC Key was originally designed for dairy cattle and is not necessarily suitable for Japanese Black (JB) beef cattle. This study revealed the lymphocyte counts in the BLV-free and -infected JB cattle were significantly lower than those in the Holstein cattle. Therefore, applying the EC Key to JB cattle could result in a large number of undetected BLV-infected cattle. Our proposed hematological key, which was designed for JB cattle, improves the detection of BLV-infected cattle by approximately 20%. We believe that this study could help promote BLV control.

  2. An anti-CD3/anti-CLL-1 bispecific antibody for the treatment of acute myeloid leukemia.

    Science.gov (United States)

    Leong, Steven R; Sukumaran, Siddharth; Hristopoulos, Maria; Totpal, Klara; Stainton, Shannon; Lu, Elizabeth; Wong, Alfred; Tam, Lucinda; Newman, Robert; Vuillemenot, Brian R; Ellerman, Diego; Gu, Chen; Mathieu, Mary; Dennis, Mark S; Nguyen, Allen; Zheng, Bing; Zhang, Crystal; Lee, Genee; Chu, Yu-Waye; Prell, Rodney A; Lin, Kedan; Laing, Steven T; Polson, Andrew G

    2017-02-02

    Acute myeloid leukemia (AML) is a major unmet medical need. Most patients have poor long-term survival, and treatment has not significantly changed in 40 years. Recently, bispecific antibodies that redirect the cytotoxic activity of effector T cells by binding to CD3, the signaling component of the T-cell receptor, and a tumor target have shown clinical activity. Notably, blinatumomab is approved to treat relapsed/refractory acute lymphoid leukemia. Here we describe the design, discovery, pharmacologic activity, pharmacokinetics, and safety of a CD3 T cell-dependent bispecific (TDB) full-length human IgG1 therapeutic antibody targeting CLL-1 that could potentially be used in humans to treat AML. CLL-1 is prevalent in AML and, unlike other targets such as CD33 and CD123, is not expressed on hematopoietic stem cells providing potential hematopoietic recovery. We selected a high-affinity monkey cross-reactive anti-CLL-1 arm and tested several anti-CD3 arms that varied in affinity, and determined that the high-affinity CD3 arms were up to 100-fold more potent in vitro. However, in mouse models, the efficacy differences were less pronounced, probably because of prolonged exposure to TDB found with lower-affinity CD3 TDBs. In monkeys, assessment of safety and target cell depletion by the high- and low-affinity TDBs revealed that only the low-affinity CD3/CLL1 TDB was well tolerated and able to deplete target cells. Our data suggest that an appropriately engineered CLL-1 TDB could be effective in the treatment of AML. © 2017 by The American Society of Hematology.

  3. A human monoclonal antibody drug and target discovery platform for B-cell chronic lymphocytic leukemia based on allogeneic hematopoietic stem cell transplantation and phage display

    OpenAIRE

    Baskar, Sivasubramanian; Suschak, Jessica M.; Samija, Ivan; Srinivasan, Ramaprasad; Childs, Richard W.; Pavletic, Steven Z.; Bishop, Michael R.; Rader, Christoph

    2009-01-01

    Allogeneic hematopoietic stem cell transplantation (alloHSCT) is the only potentially curative treatment available for patients with B-cell chronic lymphocytic leukemia (B-CLL). Here, we show that post-alloHSCT antibody repertoires can be mined for the discovery of fully human monoclonal antibodies to B-CLL cell-surface antigens. Sera collected from B-CLL patients at defined times after alloHSCT showed selective binding to primary B-CLL cells. Pre-alloHSCT sera, donor sera, and control sera w...

  4. Quantification of Lyssavirus-Neutralizing Antibodies Using Vesicular Stomatitis Virus Pseudotype Particles.

    Science.gov (United States)

    Moeschler, Sarah; Locher, Samira; Conzelmann, Karl-Klaus; Krämer, Beate; Zimmer, Gert

    2016-09-16

    Rabies is a highly fatal zoonotic disease which is primarily caused by rabies virus (RABV) although other members of the genus Lyssavirus can cause rabies as well. As yet, 14 serologically and genetically diverse lyssaviruses have been identified, mostly in bats. To assess the quality of rabies vaccines and immunoglobulin preparations, virus neutralization tests with live RABV are performed in accordance with enhanced biosafety standards. In the present work, a novel neutralization test is presented which takes advantage of a modified vesicular stomatitis virus (VSV) from which the glycoprotein G gene has been deleted and replaced by reporter genes. This single-cycle virus was trans-complemented with RABV envelope glycoprotein. Neutralization of this pseudotype virus with RABV reference serum or immune sera from vaccinated mice showed a strong correlation with the rapid fluorescent focus inhibition test (RFFIT). Importantly, pseudotype viruses containing the envelope glycoproteins of other lyssaviruses were neutralized by reference serum to a significantly lesser extent or were not neutralized at all. Taken together, a pseudotype virus system has been successfully developed which allows the safe, fast, and sensitive detection of neutralizing antibodies directed against different lyssaviruses.

  5. Quantification of Lyssavirus-Neutralizing Antibodies Using Vesicular Stomatitis Virus Pseudotype Particles

    Directory of Open Access Journals (Sweden)

    Sarah Moeschler

    2016-09-01

    Full Text Available Rabies is a highly fatal zoonotic disease which is primarily caused by rabies virus (RABV although other members of the genus Lyssavirus can cause rabies as well. As yet, 14 serologically and genetically diverse lyssaviruses have been identified, mostly in bats. To assess the quality of rabies vaccines and immunoglobulin preparations, virus neutralization tests with live RABV are performed in accordance with enhanced biosafety standards. In the present work, a novel neutralization test is presented which takes advantage of a modified vesicular stomatitis virus (VSV from which the glycoprotein G gene has been deleted and replaced by reporter genes. This single-cycle virus was trans-complemented with RABV envelope glycoprotein. Neutralization of this pseudotype virus with RABV reference serum or immune sera from vaccinated mice showed a strong correlation with the rapid fluorescent focus inhibition test (RFFIT. Importantly, pseudotype viruses containing the envelope glycoproteins of other lyssaviruses were neutralized by reference serum to a significantly lesser extent or were not neutralized at all. Taken together, a pseudotype virus system has been successfully developed which allows the safe, fast, and sensitive detection of neutralizing antibodies directed against different lyssaviruses.

  6. Structure-Based Design of Hepatitis C Virus Vaccines That Elicit Neutralizing Antibody Responses to a Conserved Epitope

    Energy Technology Data Exchange (ETDEWEB)

    Pierce, Brian G.; Boucher, Elisabeth N.; Piepenbrink, Kurt H.; Ejemel, Monir; Rapp, Chelsea A.; Thomas, William D.; Sundberg, Eric J.; Weng, Zhiping; Wang, Yang; Diamond, Michael S.

    2017-08-09

    Despite recent advances in therapeutic options, hepatitis C virus (HCV) remains a severe global disease burden, and a vaccine can substantially reduce its incidence. Due to its extremely high sequence variability, HCV can readily escape the immune response; thus, an effective vaccine must target conserved, functionally important epitopes. Using the structure of a broadly neutralizing antibody in complex with a conserved linear epitope from the HCV E2 envelope glycoprotein (residues 412 to 423; epitope I), we performed structure-based design of immunogens to induce antibody responses to this epitope. This resulted in epitope-based immunogens based on a cyclic defensin protein, as well as a bivalent immunogen with two copies of the epitope on the E2 surface. We solved the X-ray structure of a cyclic immunogen in complex with the HCV1 antibody and confirmed preservation of the epitope conformation and the HCV1 interface. Mice vaccinated with our designed immunogens produced robust antibody responses to epitope I, and their serum could neutralize HCV. Notably, the cyclic designs induced greater epitope-specific responses and neutralization than the native peptide epitope. Beyond successfully designing several novel HCV immunogens, this study demonstrates the principle that neutralizing anti-HCV antibodies can be induced by epitope-based, engineered vaccines and provides the basis for further efforts in structure-based design of HCV vaccines.

    IMPORTANCEHepatitis C virus is a leading cause of liver disease and liver cancer, with approximately 3% of the world's population infected. To combat this virus, an effective vaccine would have distinct advantages over current therapeutic options, yet experimental vaccines have not been successful to date, due in part to the virus's high sequence variability leading to immune escape. In this study, we rationally designed several vaccine immunogens based on the structure of a conserved epitope that

  7. Antibody titers for canine parvovirus type-2, canine distemper virus, and canine adenovirus type-1 in adult household dogs.

    Science.gov (United States)

    Taguchi, Masayuki; Namikawa, Kazuhiko; Maruo, Takuya; Orito, Kensuke; Lynch, Jonathan; Sahara, Hiroeki

    2011-09-01

    Serum antibody titers for canine parvovirus type-2 (CPV-2), canine distemper virus (CDV) and canine adenovirus type-1 (CAV-1) were investigated in 1031 healthy adult household dogs (2 to 18 years old) given an annual inoculation in the previous 11 to 13 months. The number of dogs retaining significant titers of antibodies against CPV-2, CDV, and CAV-1 were 888 (86%), 744 (72%), and 732 (71%), respectively. There were no differences between males and females in antibody titers against the 3 viruses. Antibody titer for CPV-2 was significantly higher in younger dogs than in older dogs, CDV antibody was significantly higher in older dogs than in younger dogs, and CAV titer was not associated with age.

  8. IL-15 enhances cross-reactive antibody recall responses to seasonal H3 influenza viruses in vitro [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Junqiong Huang

    2017-11-01

    Full Text Available Background: Recently, several human monoclonal antibodies that target conserved epitopes on the stalk region of influenza hemagglutinin (HA have shown broad reactivity to influenza A subtypes. Also, vaccination with recombinant chimeric HA or stem fragments from H3 influenza viruses induce broad immune protection in mice and humans. However, it is unclear whether stalk-binding antibodies can be induced in human memory B cells by seasonal H3N2 viruses. Methods: In this study, we recruited 13 donors previously exposed to H3 viruses, the majority (12 of 13 of which had been immunized with seasonal influenza vaccines. We evaluated plasma baseline strain-specific and stalk-reactive anti-HA antibodies and B cell recall responses to inactivated H3N2 A/Victoria/361/2011 virus in vitro using a high throughput multiplex (mPlex-Flu assay. Results: Stalk-reactive IgG was detected in the plasma of 7 of the subjects. Inactivated H3 viral particles rapidly induced clade cross-reactive antibodies in B cell cultures derived from all 13 donors. In addition, H3 stalk-reactive antibodies were detected in culture supernatants from 7 of the 13 donors (53.8%.  H3 stalk-reactive antibodies were also induced by H1 and H7 subtypes. Interestingly, broadly cross-reactive antibody recall responses to H3 strains were also enhanced by stimulating B cells in vitro with CpG2006 ODN in the presence of IL-15. H3 stalk-reactive antibodies were detected in  CpG2006 ODN + IL-15 stimulated B cell cultures derived from 12 of the 13 donors (92.3%, with high levels detected in cultures from 7 of the 13 donors. Conclusions: Our results demonstrate that stalk-reactive antibody recall responses induced by seasonal H3 viruses and CpG2006 ODN can be enhanced by IL-15.

  9. Osteochondroma in a young cat infected by feline leukemia virus

    Directory of Open Access Journals (Sweden)

    Matheus de Oliveira Reis

    Full Text Available ABSTRACT: Osteochondromas are primary bone tumors characterized by cartilage-covered bone projections involving single or multiple masses (osteochondromatosis. This study reports the clinical and pathological findings from a young domestic cat with osteochondroma in the humerus. During the clinical evaluation, the animal had pronounced right forelimb musculature atrophy and an increased distal humeral volume. Histopathological examination of the neoplasm revealed a proliferative lesion characterized mostly by endochondral ossification and peripheral foci of proliferating cartilage tissue. Further testing using immunohistochemical staining and polymerase chain reaction revealed the presence of feline leukemia virus antigens in the hematopoietic cells of the bone marrow and FeLV proviral DNA in the peripheral blood lymphocytes. Clinical and pathological findings are consistent with osteochondroma. This neoplasm occurred in an eight-month-old feline with humeral enlargement that had been present since two months old.

  10. Macropinocytosis is the Entry Mechanism of Amphotropic Murine Leukemia Virus

    DEFF Research Database (Denmark)

    Rasmussen, Izabela; Vilhardt, Frederik

    2015-01-01

    of infection. Understanding how pathogens and toxins exploit or divert endocytosis pathways has advanced our understanding of membrane trafficking pathways, which benefits development of new therapeutical schemes and methods of drug delivery. We show here that Murine Leukemia Virus (A-MLV) pseudotyped......, or NIH-3T3 cells knocked-down for caveolin expression, was unaffected. Conversely, A-MLV infection of NIH-3T3 and HeLa cells was sensitive to amiloride analogues and actin-depolymerizing drugs that interfere with macropinocytosis. Further manipulation of the actin cytoskeleton through conditional...... with the amphotropic (expands the host range to many mammalian cells) envelope protein gains entry into host cells by macropinocytosis. Macropinosomes form as large, fluid-filled vacuoles (up to 10 μm) following collapse of cell surface protrusions and membrane scission. We use drugs or introduction of mutant proteins...

  11. Fluorescence Adherence Inhibition Assay: A Novel Functional Assessment of Blocking Virus Attachment by Vaccine-Induced Antibodies.

    Directory of Open Access Journals (Sweden)

    Atul Asati

    Full Text Available Neutralizing antibodies induced by vaccination or natural infection play a critically important role in protection against the viral diseases. In general, neutralization of the viral infection occurs via two major pathways: pre- and post-attachment modes, the first being the most important for such infections as influenza and polio, the latter being significant for filoviruses. Neutralizing capacity of antibodies is typically evaluated by virus neutralization assays that assess reduction of viral infectivity to the target cells in the presence of functional antibodies. Plaque reduction neutralization test, microneutralization and immunofluorescent assays are often used as gold standard virus neutralization assays. However, these methods are associated with several important prerequisites such as use of live virus requiring safety precautions, tedious evaluation procedure and long assessment time. Hence, there is a need for a robust, inexpensive high throughput functional assay that can be performed rapidly using inactivated virus, without extensive safety precautions. Herein, we report a novel high throughput Fluorescence Adherence Inhibition assay (fADI using inactivated virus labeled with fluorescent secondary antibodies virus and Vero cells or erythrocytes as targets. It requires only few hours to assess pre-attachment neutralizing capacity of donor sera. fADI assay was tested successfully on donors immunized with polio, yellow fever and influenza vaccines. To further simplify and improve the throughput of the assay, we have developed a mathematical approach for calculating the 50% titers from a single sample dilution, without the need to analyze multi-point titration curves. Assessment of pre- and post-vaccination human sera from subjects immunized with IPOL®, YF-VAX® and 2013-2014 Fluzone® vaccines demonstrated high efficiency of the assay. The results correlated very well with microneutralization assay performed independently by the FDA

  12. Dengue, Japanese encephalitis and Chikungunya virus antibody prevalence among captive monkey (Macaca nemestrina) colonies of Northern Thailand.

    Science.gov (United States)

    Nakgoi, Khajornpong; Nitatpattana, Narong; Wajjwalku, Worawidh; Pongsopawijit, Pornsawan; Kaewchot, Supakarn; Yoksan, Sutee; Siripolwat, Voravit; Souris, Marc; Gonzalez, Jean-Paul

    2014-01-01

    The potential of macaque Macaca nemestrina leonina in Thailand to be infected by endemic arboviruses was assessed. The prevalence of antibodies of three arboviruses actively circulating in Thailand was determined by Plaque Reduction Neutralization assay procedures using samples from captive colonies in Northern Thailand. Out of 38 macaques, 9 (24%) presented reacting antibodies against dengue virus, 5 (13%) against Japanese encephalitis virus, and 4 (10%) against Chikungunya virus. Our results indicate that the northern pig-tailed macaque in Thailand can be infected by these arboviruses, inferring therefore that their virus specific vectors have bitten them. Given that, northern pig-tailed macaque represents an abundant population, living in close range to human or in peridomestic setting, they could play a role as potential reservoir host for arboviruses circulating in Thailand. © 2013 Wiley Periodicals, Inc.

  13. Novel rabies virus-neutralizing epitope recognized by human monoclonal antibody: Fine mapping and escape mutant analysis

    NARCIS (Netherlands)

    Marissen, W.E.; Kramer, R.A.; Rice, A.; Weldon, W.C.; Niezgoda, M.; Faber, M.; Slootstra, J.W.; Meloen, R.H.; Clijsters-van der Horst, M.; Visser, T.J.; Jongeneelen, M.; Thijsse, S.; Throsby, M.; Kruif, de J.; Rupprecht, C.E.; Dietzschold, B.; Goudsmit, J.; Bakker, A.B.H.

    2005-01-01

    Anti-rabies virus immunoglobulin combined with rabies vaccine protects humans from lethal rabies infections. For cost and safety reasons, replacement of the human or equine polyclonal immunoglobulin is advocated, and the use of rabies virus-specific monoclonal antibodies (MAbs) is recommended. We

  14. Novel rabies virus-neutralizing epitope recognized by human monoclonal antibody: fine mapping and escape mutant analysis

    NARCIS (Netherlands)

    Marissen, Wilfred E.; Kramer, R. Arjen; Rice, Amy; Weldon, William C.; Niezgoda, Michael; Faber, Milosz; Slootstra, Jerry W.; Meloen, Rob H.; Clijsters-van der Horst, Marieke; Visser, Therese J.; Jongeneelen, Mandy; Thijsse, Sandra; Throsby, Mark; de Kruif, John; Rupprecht, Charles E.; Dietzschold, Bernhard; Goudsmit, Jaap; Bakker, Alexander B. H.

    2005-01-01

    Anti-rabies virus immunoglobulin combined with rabies vaccine protects humans from lethal rabies infections. For cost and safety reasons, replacement of the human or equine polyclonal immunoglobulin is advocated, and the use of rabies virus-specific monoclonal antibodies (MAbs) is recommended. We

  15. Coccidian and nematode infections influence prevalence of antibody to myxoma and rabbit hemorrhagic disease viruses in European rabbits.

    Science.gov (United States)

    Bertó-Moran, Alejandro; Pacios, Isabel; Serrano, Emmanuel; Moreno, Sacramento; Rouco, Carlos

    2013-01-01

    The interaction among several parasites in European rabbits (Oryctolagus cuniculus) is crucial to host fitness and to the epidemiology of myxomatosis and rabbit hemorrhagic disease. These diseases have caused significant reductions in rabbit populations on the Iberian Peninsula. Most studies have focused on the epidemiology and pathogenesis of these viruses individually, and little is known about interactions between these viruses and other parasites. Taking advantage of an experimental restocking program in Spain, the effects of coccidian and nematode infections on the probability of having detectable antibody to myxoma and rabbit hemorrhagic disease viruses were tested in European wild rabbits. For 14 mo, we monitored rabbit abundance and parasite loads (coccidia and nematodes) in three reintroduced rabbit populations. While coccidian and nematode loads explained seasonal antibody prevalences to myxoma virus, the pattern was less clear for rabbit hemorrhagic disease. Contrary to expectations, prevalence of antibody to myxoma virus was inversely proportional to coccidian load, while nematode load seemed to play a minor role. These results have implications for viral disease epidemiology and for disease management intended to increase rabbit populations in areas where they are important for ecosystem conservation.

  16. Comprehensive mapping of common immunodominant epitopes in the West Nile virus nonstructural protein 1 recognized by avian antibody responses.

    Directory of Open Access Journals (Sweden)

    Encheng Sun

    Full Text Available West Nile virus (WNV is a mosquito-borne flavivirus that primarily infects birds but occasionally infects humans and horses. Certain species of birds, including crows, house sparrows, geese, blue jays and ravens, are considered highly susceptible hosts to WNV. The nonstructural protein 1 (NS1 of WNV can elicit protective immune responses, including NS1-reactive antibodies, during infection of animals. The antigenicity of NS1 suggests that NS1-reactive antibodies could provide a basis for serological diagnostic reagents. To further define serological reagents for diagnostic use, the antigenic sites in NS1 that are targeted by host immune responses need to be identified and the potential diagnostic value of individual antigenic sites also needs to be defined. The present study describes comprehensive mapping of common immunodominant linear B-cell epitopes in the WNV NS1 using avian WNV NS1 antisera. We screened antisera from chickens, ducks and geese immunized with purified NS1 for reactivity against 35 partially overlapping peptides covering the entire WNV NS1. This study identified twelve, nine and six peptide epitopes recognized by chicken, duck and goose antibody responses, respectively. Three epitopes (NS1-3, 14 and 24 were recognized by antibodies elicited by immunization in all three avian species tested. We also found that NS1-3 and 24 were WNV-specific epitopes, whereas the NS1-14 epitope was conserved among the Japanese encephalitis virus (JEV serocomplex viruses based on the reactivity of avian WNV NS1 antisera against polypeptides derived from the NS1 sequences of viruses of the JEV serocomplex. Further analysis showed that the three common polypeptide epitopes were not recognized by antibodies in Avian Influenza Virus (AIV, Newcastle Disease Virus (NDV, Duck Plague Virus (DPV and Goose Parvovirus (GPV antisera. The knowledge and reagents generated in this study have potential applications in differential diagnostic approaches and

  17. Altered plasma concentrations of sex hormones in cats infected by feline immunodeficiency virus or feline leukemia virus.

    Science.gov (United States)

    Tejerizo, G; Doménech, A; Illera, J-C; Silván, G; Gómez-Lucía, E

    2012-02-01

    Gender differences may affect human immunodeficiency virus (HIV) infection in humans and may be related to fluctuations in sex hormone concentration. The different percentage of male and female cats observed to be infected by feline leukemia virus (FeLV) or feline immunodeficiency virus (FIV) has been traditionally explained through the transmission mechanisms of both viruses. However, sexual hormones may also play a role in this different distribution. To study this possibility, 17β-estradiol, progesterone, testosterone, and dehydroepiandrosterone (DHEA) concentrations were analyzed using a competitive enzyme immunoassay in the plasma of 258 cats naturally infected by FIV (FIV(+)), FeLV (FeLV(+)), or FeLV and FIV (F(-)F(+)) or negative for both viruses, including both sick and clinically healthy animals. Results indicated that the concentrations of 17β-estradiol and testosterone were significantly higher in animals infected with FIV or FeLV (P < 0.05) than in negative cats. Plasma concentrations of DHEA in cats infected by either retrovirus were lower than in negative animals (P < 0.05), and F(-)F(+) cats had significantly lower plasma values than monoinfected cats (P < 0.05). No significant differences were detected in the plasma concentration of progesterone of the four groups. No relevant differences were detected in the hormone concentrations between animal genders, except that FIV(+) females had higher DHEA concentrations than the corresponding males (P < 0.05). In addition, no differences were observed in the hormone concentrations between retrovirus-infected and noninfected animals with and without clinical signs. These results suggest that FIV and FeLV infections are associated with an important deregulation of steroids, possibly from early in the infection process, which might have decisive consequences for disease progression. Copyright © 2012 Elsevier Inc. All rights reserved.

  18. Endogenous retrovirus and radiation-induced leukemia in the RMF mouse

    International Nuclear Information System (INIS)

    Tennant, R.W.; Boone, L.R.; Lalley, P.; Yang, W.K.

    1982-01-01

    The induction of myeloid leukemia in irradiated RFM/Un mice has been associated with retrovirus infection. However, two characteristics of this strain complicate efforts to define the role of the virus. This strain possesses only one inducible host range class of endogenous virus and a unique gene, in addition to the Fv-1/sup n/ locus, which specifically restricts exogenous infection by endogenous viruses. These characteristics possibly account for absence of recombinant viruses in this strain, even though virus is amply expressed during most of the animal's life span. We have examined further the distribution of retrovirus sequences and the chromosomal locus of the inducible virus in this strain. This report describes evidence for additional viral sequences in cells of a radiation-induced myeloid leukemia line and discusses the possible origin of these added copies

  19. Avian influenza virus antibodies in Pacific Coast Red Knots (Calidris canutus rufa)

    Science.gov (United States)

    Johnson, James A.; DeCicco, Lucas H.; Ruthrauff, Daniel R.; Krauss, Scott; Hall, Jeffrey S.

    2014-01-01

    Prevalence of avian influenza virus (AIV) antibodies in the western Atlantic subspecies of Red Knot (Calidris canutus rufa) is among the highest for any shorebird. To assess whether the frequency of detection of AIV antibodies is high for the species in general or restricted only to C. c. rufa, we sampled the northeastern Pacific Coast subspecies of Red Knot (Calidris canutus roselaari) breeding in northwestern Alaska. Antibodies were detected in 90% of adults and none of the chicks sampled. Viral shedding was not detected in adults or chicks. These results suggest a predisposition of Red Knots to AIV infection. High antibody titers to subtypes H3 and H4 were detected, whereas low to intermediate antibody levels were found for subtypes H10 and H11. These four subtypes have previously been detected in shorebirds at Delaware Bay (at the border of New Jersey and Delaware) and in waterfowl along the Pacific Coast of North America.

  20. Application of solid-phase radioimmunoassay in determining antibodies to Aujeszky's disease virus in blood serum of vaccinated pigs

    International Nuclear Information System (INIS)

    Rodak, L.; Smid, B.; Valicek, L.

    1983-01-01

    In the blood sera of pigs vaccinated with inactivated vaccines manufactured by three different manufacturers the RIA method was used to determine the specific antibodies to the virus of Aujeszky's disease. In certain groups of vaccinated pigs the results of the RIA examination are unfavourably affected by the bond of antibodies to the cellular antigenous determinants. This proves that following vaccination antibodies are formed not only against the viral antigen but also against the antigens of cells on which the vaccination virus is propagated. These shortcomings are eliminated by the use of suitable cellular cultures for the preparation of viral and control antigens. Antigens are applicable for RIA and for ELISA examinations of blood sera of infected and vaccinated pigs. The advantages are described of the RIA and ELISA methods as compared with the virus neutralization test. (author)

  1. Application of solid-phase radioimmunoassay in determining antibodies to Aujeszky's disease virus in blood serum of vaccinated pigs

    Energy Technology Data Exchange (ETDEWEB)

    Rodak, L; Smid, B; Valicek, L [Vyzkumny Ustav Veterinarniho Lekarstvi, Brno-Medlanky (Czechoslovakia)

    1983-11-01

    In the blood sera of pigs vaccinated with inactivated vaccines manufactured by three different manufacturers the RIA method was used to determine the specific antibodies to the virus of Aujeszky's disease. In certain groups of vaccinated pigs the results of the RIA examination are unfavourably affected by the bond of antibodies to the cellular antigenous determinants. This proves that following vaccination antibodies are formed not only against the viral antigen but also against the antigens of cells on which the vaccination virus is propagated. These shortcomings are eliminated by the use of suitable cellular cultures for the preparation of viral and control antigens. Antigens are applicable for RIA and for ELISA examinations of blood sera of infected and vaccinated pigs. The advantages are described of the RIA and ELISA methods as compared with the virus neutralization test.

  2. Antibody response in the female rabbit reproductive tract to influenza haemagglutinin encoded by a recombinant myxoma virus

    International Nuclear Information System (INIS)

    Gu Wenyi; Holland, Michael; Janssens, Peter; Kerr, Peter

    2003-01-01

    The antibody response in serum and the reproductive tract of female rabbits to a model antigen, influenza virus haemagglutinin (HA), encoded by a recombinant myxoma virus was investigated. Strong and lasting IgG antibody responses to HA were induced in serum following intradermal, intranasal, and intravaginal immunisations. HA IgG was also detected in reproductive tract fluids but was only about 1% the titer of that in serum. HA IgA was not detected in serum of any infected groups and was occasionally detected in reproductive tract fluids at a low titer only after infections through mucosal sites. HA IgM was also detected only in some of the reproductive tract fluids at very low levels. Induction of ovulation did not change these patterns and B cell homing to the reproductive tract was not profound. In contrast, HA IgG and IgM titers in ovarian follicular fluids were comparable to that in serum. These data suggest that if this virus is used to deliver an immunocontraceptive vaccine that requires a high-level antibody response, the target antigen needs to be accessible to serum antibody or in the ovary

  3. Targeting the CXCR4 pathway using a novel anti-CXCR4 IgG1 antibody (PF-06747143 in chronic lymphocytic leukemia

    Directory of Open Access Journals (Sweden)

    Manoj K. Kashyap

    2017-05-01

    Full Text Available Abstract Background The CXCR4-CXCL12 axis plays an important role in the chronic lymphocytic leukemia (CLL-microenvironment interaction. Overexpression of CXCR4 has been reported in different hematological malignancies including CLL. Binding of the pro-survival chemokine CXCL12 with its cognate receptor CXCR4 induces cell migration. CXCL12/CXCR4 signaling axis promotes cell survival and proliferation and may contribute to the tropism of leukemia cells towards lymphoid tissues and bone marrow. Therefore, we hypothesized that targeting CXCR4 with an IgG1 antibody, PF-06747143, may constitute an effective therapeutic approach for CLL. Methods Patient-derived primary CLL-B cells were assessed for cytotoxicity in an in vitro model of CLL microenvironment. PF-06747143 was analyzed for cell death induction and for its potential to interfere with the chemokine CXCL12-induced mechanisms, including migration and F-actin polymerization. PF-06747143 in vivo efficacy was determined in a CLL murine xenograft tumor model. Results PF-06747143, a novel-humanized IgG1 CXCR4 antagonist antibody, induced cell death of patient-derived primary CLL-B cells, in presence or absence of stromal cells. Moreover, cell death induction by the antibody was independent of CLL high-risk prognostic markers. The cell death mechanism was dependent on CXCR4 expression, required antibody bivalency, involved reactive oxygen species production, and did not require caspase activation, all characteristics reminiscent of programmed cell death (PCD. PF-06747143 also induced potent B-CLL cytotoxicity via Fc-driven antibody-dependent cell-mediated cytotoxicity (ADCC and complement-dependent cytotoxicity activity (CDC. PF-06747143 had significant combinatorial effect with standard of care (SOC agents in B-CLL treatment, including rituximab, fludarabine (F-ara-A, ibrutinib, and bendamustine. In a CLL xenograft model, PF-06747143 decreased tumor burden and improved survival as a monotherapy

  4. Structures of protective antibodies reveal sites of vulnerability on Ebola virus.

    Science.gov (United States)

    Murin, Charles D; Fusco, Marnie L; Bornholdt, Zachary A; Qiu, Xiangguo; Olinger, Gene G; Zeitlin, Larry; Kobinger, Gary P; Ward, Andrew B; Saphire, Erica Ollmann

    2014-12-02

    Ebola virus (EBOV) and related filoviruses cause severe hemorrhagic fever, with up to 90% lethality, and no treatments are approved for human use. Multiple recent outbreaks of EBOV and the likelihood of future human exposure highlight the need for pre- and postexposure treatments. Monoclonal antibody (mAb) cocktails are particularly attractive candidates due to their proven postexposure efficacy in nonhuman primate models of EBOV infection. Two candidate cocktails, MB-003 and ZMAb, have been extensively evaluated in both in vitro and in vivo studies. Recently, these two therapeutics have been combined into a new cocktail named ZMapp, which showed increased efficacy and has been given compassionately to some human patients. Epitope information and mechanism of action are currently unknown for most of the component mAbs. Here we provide single-particle EM reconstructions of every mAb in the ZMapp cocktail, as well as additional antibodies from MB-003 and ZMAb. Our results illuminate key and recurring sites of vulnerability on the EBOV glycoprotein and provide a structural rationale for the efficacy of ZMapp. Interestingly, two of its components recognize overlapping epitopes and compete with each other for binding. Going forward, this work now provides a basis for strategic selection of next-generation antibody cocktails against Ebola and related viruses and a model for predicting the impact of ZMapp on potential escape mutations in ongoing or future Ebola outbreaks.

  5. Antibody Responses to Marburg Virus in Egyptian Rousette Bats and Their Role in Protection against Infection.

    Science.gov (United States)

    Storm, Nadia; Jansen Van Vuren, Petrus; Markotter, Wanda; Paweska, Janusz T

    2018-02-10

    Egyptian rousette bats (ERBs) are reservoir hosts for the Marburg virus (MARV). The immune dynamics and responses to MARV infection in ERBs are poorly understood, and limited information exists on the role of antibodies in protection of ERBs against MARV infection. Here, we determine the duration of maternal immunity to MARV in juvenile ERBs, and evaluate the duration of the antibody response to MARV in bats naturally or experimentally infected with the virus. We further explore whether antibodies in previously naturally exposed bats is fully protective against experimental reinfection with MARV. Maternal immunity was lost in juvenile ERBs by 5 months of age. Antibodies to MARV remained detectable in 67% of experimentally infected bats approximately 4 months post inoculation (p.i.), while antibodies to MARV remained present in 84% of naturally exposed bats at least 11 months after capture. Reinfection of seropositive ERBs with MARV produced an anamnestic response from day 5 p.i. Although PCR-defined viremia was present in 73.3% of reinfected ERBs, replicating virus was recovered from the serum of only one bat on day 3 p.i. The negative PCR results in the salivary glands, intestines, bladders and reproductive tracts of reinfected bats, and the apparent absence of MARV in the majority of swabs collected from these bats suggest that reinfection may only play a minor role in the transmission and maintenance of MARV amongst ERBs in nature.

  6. Antibody Persistence in Adults Two Years after Vaccination with an H1N1 2009 Pandemic Influenza Virus-Like Particle Vaccine.

    Directory of Open Access Journals (Sweden)

    Nuriban Valero-Pacheco

    Full Text Available The influenza virus is a human pathogen that causes epidemics every year, as well as potential pandemic outbreaks, as occurred in 2009. Vaccination has proven to be sufficient in the prevention and containment of viral spreading. In addition to the current egg-based vaccines, new and promising vaccine platforms, such as cell culture-derived vaccines that include virus-like particles (VLPs, have been developed. VLPs have been shown to be both safe and immunogenic against influenza infections. Although antibody persistence has been studied in traditional egg-based influenza vaccines, studies on antibody response durations induced by VLP influenza vaccines in humans are scarce. Here, we show that subjects vaccinated with an insect cell-derived VLP vaccine, in the midst of the 2009 H1N1 influenza pandemic outbreak in Mexico City, showed antibody persistence up to 24 months post-vaccination. Additionally, we found that subjects that reported being revaccinated with a subsequent inactivated influenza virus vaccine showed higher antibody titres to the pandemic influenza virus than those who were not revaccinated. These findings provide insights into the duration of the antibody responses elicited by an insect cell-derived pandemic influenza VLP vaccine and the possible effects of subsequent influenza vaccination on antibody persistence induced by this VLP vaccine in humans.

  7. Tissue localization, shedding, virus carriage, antibody response, and aerosol transmission of porcine epidemic diarrhea virus (PEDV) following inoculation of 4 week-old feeder pigs

    Science.gov (United States)

    Porcine epidemic diarrhea virus (PEDV) emerged in the U.S. in April 2013 and caused significant losses to the swine industry. The purpose of this investigation was to determine tissue localization, shedding patterns, virus carriage, antibody response, and aerosol transmission of PEDV following inocu...

  8. Virus neutralizing antibody response in mice and dogs with a bicistronic DNA vaccine encoding rabies virus glycoprotein and canine parvovirus VP2.

    Science.gov (United States)

    Patial, Sonika; Chaturvedi, V K; Rai, A; Saini, M; Chandra, Rajesh; Saini, Y; Gupta, Praveen K

    2007-05-16

    A bicistronic DNA vaccine against rabies and parvovirus infection of dogs was developed by subcloning rabies glycoprotein and canine parvovirus (CPV) VP2 genes into a bicistronic vector. After characterizing the expression of both the proteins in vitro, the bicistronic DNA vaccine was injected in mice and induced immune response was compared with monocistronic DNA vaccines. There was no significant difference in ELISA and virus neutralizing (VN) antibody responses against rabies and CPV in mice immunized with either bicistronic or monocistronic DNA vaccine. Further, there was significantly similar protection in mice immunized with either bicistronic or monocistronic rabies DNA vaccine on rabies virus challenge. Similarly, dogs immunized with monocistronic and bicistronic DNA vaccines developed comparable VN antibodies against rabies and CPV. This study indicated that bicistronic DNA vaccine can be used in dogs to induce virus neutralizing immune responses against both rabies and CPV.

  9. Antibody quality and protection from lethal Ebola virus challenge in nonhuman primates immunized with rabies virus based bivalent vaccine.

    Science.gov (United States)

    Blaney, Joseph E; Marzi, Andrea; Willet, Mallory; Papaneri, Amy B; Wirblich, Christoph; Feldmann, Friederike; Holbrook, Michael; Jahrling, Peter; Feldmann, Heinz; Schnell, Matthias J

    2013-01-01

    We have previously described the generation of a novel Ebola virus (EBOV) vaccine platform based on (a) replication-competent rabies virus (RABV), (b) replication-deficient RABV, or (c) chemically inactivated RABV expressing EBOV glycoprotein (GP). Mouse studies demonstrated safety, immunogenicity, and protective efficacy of these live or inactivated RABV/EBOV vaccines. Here, we evaluated these vaccines in nonhuman primates. Our results indicate that all three vaccines do induce potent immune responses against both RABV and EBOV, while the protection of immunized animals against EBOV was largely dependent on the quality of humoral immune response against EBOV GP. We also determined if the induced antibodies against EBOV GP differ in their target, affinity, or the isotype. Our results show that IgG1-biased humoral responses as well as high levels of GP-specific antibodies were beneficial for the control of EBOV infection after immunization. These results further support the concept that a successful EBOV vaccine needs to induce strong antibodies against EBOV. We also showed that a dual vaccine against RABV and filoviruses is achievable; therefore addressing concerns for the marketability of this urgently needed vaccine.

  10. Antibody quality and protection from lethal Ebola virus challenge in nonhuman primates immunized with rabies virus based bivalent vaccine.

    Directory of Open Access Journals (Sweden)

    Joseph E Blaney

    Full Text Available We have previously described the generation of a novel Ebola virus (EBOV vaccine platform based on (a replication-competent rabies virus (RABV, (b replication-deficient RABV, or (c chemically inactivated RABV expressing EBOV glycoprotein (GP. Mouse studies demonstrated safety, immunogenicity, and protective efficacy of these live or inactivated RABV/EBOV vaccines. Here, we evaluated these vaccines in nonhuman primates. Our results indicate that all three vaccines do induce potent immune responses against both RABV and EBOV, while the protection of immunized animals against EBOV was largely dependent on the quality of humoral immune response against EBOV GP. We also determined if the induced antibodies against EBOV GP differ in their target, affinity, or the isotype. Our results show that IgG1-biased humoral responses as well as high levels of GP-specific antibodies were beneficial for the control of EBOV infection after immunization. These results further support the concept that a successful EBOV vaccine needs to induce strong antibodies against EBOV. We also showed that a dual vaccine against RABV and filoviruses is achievable; therefore addressing concerns for the marketability of this urgently needed vaccine.

  11. Detection of rainbow trout antibodies against viral haemorrhagic septicaemia virus (VHSV) by neutralisation test is highly dependent on the virus isolate used

    DEFF Research Database (Denmark)

    Fregeneda-Grandes, J.M.; Olesen, Niels Jørgen

    2007-01-01

    with VHS but with no clinical signs of infection. When the sera were examined by 50%PNT using the VHSV reference isolate DK-F1 or the heat attenuated DK-F25 mutant strain, no neutralizing antibodies were found. In contrast, when one of the virus isolates from the farm (homologous virus) was used in the 50...

  12. Immune responses to epstein-barr virus in atomic bomb survivors: Study of precursor frequency of cytotoxic lymphocytes and titer levels of anti-Epstein-Barr virus-related antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Kusunoki, Yoichiro; Kyoizumi, Seishi; Saito, Mayumi; Ozaki, Kyoko; Hirai, Yuko; Akiyama, Mitoshi (Radiation Effects Research Foundation, Hiroshima (Japan)); Fukuda, Yasuko (Radiation Effects Research Foundation, Hiroshima (Japan) Children' s Hospital Medical Center of Northern California, Oakland, CA (United States)); Huang, Hua (Radiation Effects Research Foundation, Hiroshima (Japan) Univ. of Wisconsin, Madison, WI (United States))

    1994-04-01

    Precursor frequencies of cytotoxic lymphocytes to autologous Epstein-Barr virus-transformed B cells and serum titers of anti-Epstein-Barr virus-related antibodies were measured in 68 atomic bomb survivors to clarify the immune mechanism controlling Epstein-Barr virus infection. The precursor frequency was negatively correlated with the titer of anti-early antigen lgG, which is probably produced at the stage of viral reactivation. A positive correlation between the precursor frequency and titer of anti-Epstein-Barr virus-associated nuclear antigen antibody was also observed, indicating that the precursor frequency reflects the degree of in vivo destruction by T cells of the virus-infected cells. These results suggest that T-cell memory specific to Epstein-Barr virus keeps the virus under control and that the precursor frequency assay is useful for the evaluation of immune responses to Epstein-Barr virus. However, no significant effect of atomic bomb radiation on the precursor frequency was observed in the present study, probably due to the limited number of participants. 24 refs., 4 figs., 2 tabs.

  13. Immune responses to epstein-barr virus in atomic bomb survivors: Study of precursor frequency of cytotoxic lymphocytes and titer levels of anti-Epstein-Barr virus-related antibodies

    International Nuclear Information System (INIS)

    Kusunoki, Yoichiro; Kyoizumi, Seishi; Saito, Mayumi; Ozaki, Kyoko; Hirai, Yuko; Akiyama, Mitoshi; Fukuda, Yasuko; Huang, Hua

    1994-01-01

    Precursor frequencies of cytotoxic lymphocytes to autologous Epstein-Barr virus-transformed B cells and serum titers of anti-Epstein-Barr virus-related antibodies were measured in 68 atomic bomb survivors to clarify the immune mechanism controlling Epstein-Barr virus infection. The precursor frequency was negatively correlated with the titer of anti-early antigen lgG, which is probably produced at the stage of viral reactivation. A positive correlation between the precursor frequency and titer of anti-Epstein-Barr virus-associated nuclear antigen antibody was also observed, indicating that the precursor frequency reflects the degree of in vivo destruction by T cells of the virus-infected cells. These results suggest that T-cell memory specific to Epstein-Barr virus keeps the virus under control and that the precursor frequency assay is useful for the evaluation of immune responses to Epstein-Barr virus. However, no significant effect of atomic bomb radiation on the precursor frequency was observed in the present study, probably due to the limited number of participants. 24 refs., 4 figs., 2 tabs

  14. In vivo activity of a mixture of two human monoclonal antibodies (anti-HBs) in a chronic hepatitis B virus carrier chimpanzee

    NARCIS (Netherlands)

    R. Heijtink; W. Paulij; P.A.C. van Bergen (Patrick); M.H. van Roosmalen (Mark); D. Rohm; B. Eichentopf (Bertram); E. Muchmore; A.D.M.E. Osterhaus (Albert); R.A. de Man (Robert)

    1999-01-01

    textabstractA 35-year-old female hepatitis B virus carrier chimpanzee was infused with one dose of a mixture of human monoclonal antibodies 9H9 and 4-7B (antibodies against hepatitis B virus surface antigen; HBsAg). Blood samples were taken before and up to 3 weeks

  15. An unexpected antibody response to an engineered influenza virus modifies CD8+ T cell responses.

    Science.gov (United States)

    Thomas, Paul G; Brown, Scott A; Yue, Wen; So, Jenny; Webby, Richard J; Doherty, Peter C

    2006-02-21

    The ovalbumin(323-339) peptide that binds H2I-A(b) was engineered into the globular heads of hemagglutinin (H) molecules from serologically non-cross-reactive H1N1 and H3N2 influenza A viruses, the aim being to analyze recall CD4+ T cell responses in a virus-induced respiratory disease. Prime/challenge experiments with these H1ova and H3ova viruses in H2(b) mice gave the predicted, ovalbumin-specific CD4+ T cell response but showed an unexpectedly enhanced, early expansion of viral epitope-specific CD8+ T cells in spleen and a greatly diminished inflammatory process in the virus-infected respiratory tract. At the same time, the primary antibody response to the H3N2 challenge virus was significantly reduced, an effect that has been associated with preexisting neutralizing antibody in other experimental systems. Analysis of serum from the H1ova-primed mice showed low-level binding to H3ova but not to the wild-type H3N2 virus. Experiments with CD4+ T cell-depleted and Ig-/- mice indicated that this cross-reactive Ig is indeed responsible for the modified pathogenesis after respiratory challenge. Furthermore, the effect does not seem to be virus-dose related, although it does require infection. These findings suggest intriguing possibilities for vaccination and, at the same time, emphasize that engineered modifications in viruses may have unintended immunological consequences.

  16. [Efficacy of siRNA on feline leukemia virus replication in vitro].

    Science.gov (United States)

    Lehmann, Melanie; Weber, Karin; Rauch, Gisep; Hofmann-Lehmann, Regina; Hosie, Margaret J; Meli, Marina L; Hartmann, Katrin

    2015-01-01

    Feline leukemia virus (FeLV) can lead to severe clinical signs in cats. Until now, there is no effective therapy for FeLV-infected cats. RNA interference-based antiviral therapy is a new concept. Specific small interfering RNA (siRNA) are designed complementary to the mRNA of a target region, and thus inhibit replication. Several studies have proven efficacy of siRNAs in inhibiting virus replication. The aim of this study was to evaluate the inhibitory potential of siRNAs against FeLV replication in vitro. siRNAs against the FeLV env gene and the host cell surface receptor (feTHTR1) which is used by FeLV-A for entry as well as siRNA that were not complementary to the FeLV or cat genome, were tested. Crandell feline kidney cells (CrFK cells) were transfected with FeLV-A/Glasgow-1. On day 13, infected cells were transfected with siRNAs. As control, cells were mock-transfected or treated with azidothymidine (AZT) (5 μg/ml). Culture supernatants were analyzed for FeLV RNA using quantitative real-time RT-PCR and for FeLV p27 by ELISA every 24 hours for five days. All siRNAs significantly reduced viral RNA and p27 production, starting after 48 hours. The fact that non-complementary siRNAs also inhibited virus replication may lead to the conclusion that unspecific mechanisms rather than specific binding lead to inhibition.

  17. EBV Positive Diffuse Large B Cell Lymphoma and Chronic Lymphocytic Leukemia Patients Exhibit Increased Anti-dUTPase Antibodies

    Directory of Open Access Journals (Sweden)

    Marshall Williams

    2018-05-01

    Full Text Available The Epstein-Barr virus (EBV, which is a ubiquitous γ-herpesvirus, establishes a latent infection in more than 90% of the global adult population. EBV-associated malignancies have increased by 14.6% over the last 20 years, and account for approximately 1.5% of all cancers worldwide and 1.8% of all cancer deaths. However, the potential involvement/contribution of lytic proteins to the pathophysiology of EBV-associated cancers is not well understood. We have previously demonstrated that the EBV-deoxyuridine triphosphate nucleotidohydrolase (dUTPase modulates innate and adaptive immune responses by engaging the Toll-Like Receptor 2 (TLR2, which leads to the modulation of downstream genes involved in oncogenesis, chronic inflammation, and in effector T-cell function. Furthermore, examination of serum samples from diffuse large B-cell lymphoma (DLBCL and chronic lymphocytic leukemia patients revealed the presence of increased levels of anti-dUTPase antibodies in both cohorts compared to controls with the highest levels (3.67-fold increase observed in DLBCL female cases and the lowest (2.12-fold increase in DLBCL males. Using computer-generated algorithms, dUTPase amino acid sequence alignments, and functional studies of BLLF3 mutants, we identified a putative amino acid motif involved with TLR2 interaction. These findings suggest that the EBV-dUTPase: TLR2 interaction is a potential molecular target that could be used for developing novel therapeutics (small molecules/vaccines.

  18. Neutralizing antibody response during human immunodeficiency virus type 1 infection: type and group specificity and viral escape

    DEFF Research Database (Denmark)

    Arendrup, M; Sönnerborg, A; Svennerholm, B

    1993-01-01

    The paradox that group-specific neutralizing antibodies (NA) exist in the majority of human immunodeficiency virus type 1 (HIV-1)-infected patients, whereas the NA response against autologous HIV-1 virus isolates is highly type-specific, motivated us to study the type- and group-specific NA...... demonstrated, suggesting that the majority of the change in neutralization sensitivity is driven by the selective pressure of type-specific NA. Furthermore, no differences were observed in sensitivity to neutralization by anti-carbohydrate neutralizing monoclonal antibodies or the lectin concanavalin A...

  19. Prevalence of antibodies against canine distemper virus among red foxes in Luxembourg

    NARCIS (Netherlands)

    B.C. Damien; S. Losch; J. Mossong; C.P. Muller (Claude); A.D.M.E. Osterhaus (Albert); B.E.E. Martina (Byron)

    2002-01-01

    textabstractCanine distemper virus (CDV) has a wide host spectrum, and during the past years, distemper has been observed in species that were previously not considered to be susceptible. In this study, we investigated the prevalence of CDV-specific antibodies in red foxes (Vulpes vulpes) sampled

  20. Prevalence of antibodies against canine distemper virus among red foxes in Luxembourg.

    NARCIS (Netherlands)

    B.C. Damien; B.E.E. Martina (Byron); S. Losch; A.D.M.E. Osterhaus (Albert); C.P. Muller (Claude)

    2002-01-01

    textabstractCanine distemper virus (CDV) has a wide host spectrum, and during the past years, distemper has been observed in species that were previously not considered to be susceptible. In this study, we investigated the prevalence of CDV-specific antibodies in red foxes (Vulpes vulpes) sampled

  1. Characterization of recombinant yellow fever-dengue vaccine viruses with human monoclonal antibodies targeting key conformational epitopes.

    Science.gov (United States)

    Lecouturier, Valerie; Berry, Catherine; Saulnier, Aure; Naville, Sophie; Manin, Catherine; Girerd-Chambaz, Yves; Crowe, James E; Jackson, Nicholas; Guy, Bruno

    2018-04-26

    The recombinant yellow fever-17D-dengue virus, live, attenuated, tetravalent dengue vaccine (CYD-TDV) is licensed in several dengue-endemic countries. Although the vaccine provides protection against dengue, the level of protection differs by serotype and warrants further investigation. We characterized the antigenic properties of each vaccine virus serotype using highly neutralizing human monoclonal antibodies (hmAbs) that bind quaternary structure-dependent epitopes. Specifically, we monitored the binding of dengue virus-1 (DENV-1; 1F4), DENV-2 (2D22) or DENV-3 (5J7) serotype-specific or DENV-1-4 cross-reactive (1C19) hmAbs to the four chimeric yellow fever-dengue vaccine viruses (CYD-1-4) included in phase III vaccine formulations using a range of biochemical and functional assays (dot blot, ELISA, surface plasmon resonance and plaque reduction neutralization assays). In addition, we used the "classic" live, attenuated DENV-2 vaccine serotype, immature CYD-2 viruses and DENV-2 virus-like particles as control antigens for anti-serotype-2 reactivity. The CYD vaccine serotypes were recognized by each hmAbs with the expected specificity, moreover, surface plasmon resonance indicated a high functional affinity interaction with the CYD serotypes. In addition, the hmAbs provided similar protection against CYD and wild-type dengue viruses in the in vitro neutralization assay. Overall, these findings demonstrate that the four CYD viruses used in clinical trials display key conformational and functional epitopes targeted by serotype-specific and/or cross-reactive neutralizing human antibodies. More specifically, we showed that CYD-2 displays serotype- specific epitopes present only on the mature virus. This indicates that the CYD-TDV has the ability to elicit antibody specificities which are similar to those induced by the wild type DENV. Future investigations will be needed to address the nature of CYD-TDV-induced responses after vaccine administration, and how these

  2. Quantitative serology assays for determination of antibody responses to Ebola virus glycoprotein and matrix protein in nonhuman primates and humans.

    Science.gov (United States)

    Vu, Hong; Shulenin, Sergey; Grolla, Allen; Audet, Jonathan; He, Shihua; Kobinger, Gary; Unfer, Robert C; Warfield, Kelly L; Aman, M Javad; Holtsberg, Frederick W

    2016-02-01

    The West Africa Ebola virus disease (EVD) outbreak has reached unprecedented magnitude and caused worldwide concerns for the spread of this deadly virus. Recent findings in nonhuman primates (NHPs) demonstrate that antibodies can be protective against EVD. However, the role of antibody response in vaccine-mediated protection is not fully understood. To address these questions quantitative serology assays are needed for measurement of the antibody response to key Ebola virus (EBOV) proteins. Serology enzyme-linked immunosorbent assays (ELISA's), using a reference detection antibody, were developed in order to standardize the quantitation of antibody levels in vaccinated NHPs or in humans exposed to EBOV or immunized with an EBOV vaccine. Critical reagents were generated to support the development of the serology ELISAs. Recombinant EBOV matrix protein (VP40) was expressed in Escherichia coli and purified. Two variants of the glycoprotein (GP), the ectodomain lacking the transmembrane domain (GPΔTM), and an engineered GP lacking the mucin-like domain (GPΔmuc) were expressed and purified from mammalian cell systems. Using these proteins, three ELISA methods were developed and optimized for reproducibility and robustness, including stability testing of critical reagents. The assay was used to determine the antibody response against VP40, GPΔTM, and GPΔmuc in a NHP vaccine study using EBOV virus-like particles (VLP) vaccine expressing GP, VP40 and the nucleoprotein. Additionally, these ELISAs were used to successfully detect antibody responses to VP40, GPΔTM and GPΔmuc in human sera from EBOV infected individuals. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. PRODUCTION OF POLYCLONAL ANTIBODY TO THE COAT PROTEIN OF CITRUS TRISTEZA VIRUS IN CHICKEN EGGS

    Directory of Open Access Journals (Sweden)

    Nurhadi Nurhadi

    2016-10-01

    Full Text Available Citrus tristeza virus (CTV is one of the most destructive diseases in many citrus growing areas of Indonesia. Effective strategies for controlling CTV depend on diagnostic procedure namely enzyme-linked immunosorbent assay (ELISA. Study aimed to purify the CTV antigen and produced its polyclonal antibody. Virion of the severe CTV isolate designated UPM/ T-002 was concentrated by polyethylene glycol (PEG precipitation combined with low speed centrifugation. Semipurified antigen was further purified by sodium dodecyl sulphatepolyacrylamide gel electrophoresis (SDS-PAGE. The specific coat protein (CP band of CTV with molecular weight of 25 kD was excised and eluted using elution buffer containing 0.25 M Tris-HCl pH 6.8 + 0.1% SDS, then used as antigen for injection into 6-month-old female of White Leghorn chicken. Results, showed than the specific polyclonal antibody raised against the 25-kDa CP had a titer of approximately 104, gave low background reaction with healthy plant sap and reacted specifically with CTV isolates. The reaction was equally strong for a severe, a moderate, a mild, and a symptomless isolate, suggesting a broad reaction range of this antibody toward different CTV isolates. Optimal virus titer can be obtained since virus loss during purification could be minimized and the highly purified antigen as an immunogen could be obtained by cutting out the CP band from SDS-PAGE gels. Large amount of highly titer of CTV antibody can be produced in chicken egg. The simplicity of the procedure makes it economically acceptable and technically adoptable because the antibody can be produced in basic laboratory.

  4. Biochemical characterization of cells transformed via transfection by feline sarcoma virus proviral DNA.

    OpenAIRE

    Rosenberg, Z F; Sahagan, B G; Snyder, H W; Worley, M B; Essex, M; Haseltine, W A

    1981-01-01

    Murine fibroblasts transformed by transfection with DNA from mink cells infected with the Snyder-Theilen strain of feline sarcoma virus and subgroup B feline leukemia virus were analyzed for the presence of integrated proviral DNA and the expression of feline leukemia virus- and feline sarcoma virus-specific proteins. The transformed murine cells harbored at least one intact feline sarcoma virus provirus, but did not contain feline leukemia virus provirus. The transformed murine cells express...

  5. Induction of human immunodeficiency virus neutralizing antibodies using fusion complexes.

    Science.gov (United States)

    Zipeto, Donato; Matucci, Andrea; Ripamonti, Chiara; Scarlatti, Gabriella; Rossolillo, Paola; Turci, Marco; Sartoris, Silvia; Tridente, Giuseppe; Bertazzoni, Umberto

    2006-05-01

    Human immunodeficiency virus-1 (HIV-1) infects cells by membrane fusion that is mediated by the envelope proteins gp120/gp41 and the cellular receptors CD4 and CCR5. During this process, some conserved viral epitopes are temporarily exposed and may induce a neutralizing antibody response when fixed in the fusogenic conformation. These transient structures are conserved and may be effective antigens for use in an anti-HIV-1 vaccine. In this study we tested different conditions of preparation of fusion complexes inducing neutralizing antibodies against both R5 and X4 tropic HIV-1 strains. Cell lines expressing HIV-1 gp120/gp41 and CD4-CCR5 were prepared and conditions for producing fusion complexes were tested. Complexes produced at different temperature and fixative combinations were used to immunize mice. Results indicated that (a) fusion complexes prepared at either 21 degrees C, 30 degrees C or 37 degrees C were immunogenic and induced neutralizing antibodies against both R5 and X4 HIV-1 heterologous isolates; (b) after extensive purification of antibodies there was no cytotoxic effect; (c) complexes prepared at 37 degrees C were more immunogenic and induced higher titers of neutralizing antibodies than complexes prepared at either 21 degrees C or 30 degrees C; (d) the fixative used did not affect the titer of neutralizing antibodies except for glutaraldehyde which was ineffective; (e) the neutralizing activity was retained after CD4-CCR5 antibody removal. The production of higher titers of neutralizing antibody with fusion complexes prepared at 37 degrees C, as compared to lower temperatures, may be related to the induction of antibodies against many different conformation intermediates that subsequently act synergistically at different steps in the fusion process.

  6. Barriers to Infection of Human Cells by Feline Leukemia Virus: Insights into Resistance to Zoonosis.

    Science.gov (United States)

    Terry, Anne; Kilbey, Anna; Naseer, Asif; Levy, Laura S; Ahmad, Shamim; Watts, Ciorsdaidh; Mackay, Nancy; Cameron, Ewan; Wilson, Sam; Neil, James C

    2017-03-01

    The human genome displays a rich fossil record of past gammaretrovirus infections, yet no current epidemic is evident, despite environmental exposure to viruses that infect human cells in vitro Feline leukemia viruses (FeLVs) rank high on this list, but neither domestic nor workplace exposure has been associated with detectable serological responses. Nonspecific inactivation of gammaretroviruses by serum factors appears insufficient to explain these observations. To investigate further, we explored the susceptibilities of primary and established human cell lines to FeLV-B, the most likely zoonotic variant. Fully permissive infection was common in cancer-derived cell lines but was also a feature of nontransformed keratinocytes and lung fibroblasts. Cells of hematopoietic origin were generally less permissive and formed discrete groups on the basis of high or low intracellular protein expression and virion release. Potent repression was observed in primary human blood mononuclear cells and a subset of leukemia cell lines. However, the early steps of reverse transcription and integration appear to be unimpaired in nonpermissive cells. FeLV-B was subject to G→A hypermutation with a predominant APOBEC3G signature in partially permissive cells but was not mutated in permissive cells or in nonpermissive cells that block secondary viral spread. Distinct cellular barriers that protect primary human blood cells are likely to be important in protection against zoonotic infection with FeLV. IMPORTANCE Domestic exposure to gammaretroviruses such as feline leukemia viruses (FeLVs) occurs worldwide, but the basis of human resistance to infection remains incompletely understood. The potential threat is evident from the human genome sequence, which reveals many past epidemics of gammaretrovirus infection, and from recent cross-species jumps of gammaretroviruses from rodents to primates and marsupials. This study examined resistance to infection at the cellular level with the most

  7. Radioimmunoassay for detection of VP1 specific neutralizing antibodies of foot and mouse disease virus

    International Nuclear Information System (INIS)

    Patzer, E.J.; Jackson, M.L.; Moore, D.M.

    1985-01-01

    A solid-phase radioimmunoassay was developed for the detection of antibodies against a specific region of the VP1 protein of the A24 and O1 serotypes of foot and mouth disease virus. The antibody titers from the radioimmunoassay showed a positive correlation with neutralizing antibody titers determined by a mouse protection assay. The specificity of the assay resides in the peptide used as antigen. The assay is rapid, reproducible and does not require the use of whole virions. (orig.)

  8. Ebola virus-like particles produced in insect cells exhibit dendritic cell stimulating activity and induce neutralizing antibodies

    International Nuclear Information System (INIS)

    Ye Ling; Lin Jianguo; Sun Yuliang; Bennouna, Soumaya; Lo, Michael; Wu Qingyang; Bu Zhigao; Pulendran, Bali; Compans, Richard W.; Yang Chinglai

    2006-01-01

    Recombinant baculoviruses (rBV) expressing Ebola virus VP40 (rBV-VP40) or GP (rBV-GP) proteins were generated. Infection of Sf9 insect cells by rBV-VP40 led to assembly and budding of filamentous particles from the cell surface as shown by electron microscopy. Ebola virus-like particles (VLPs) were produced by coinfection of Sf9 cells with rBV-VP40 and rBV-GP, and incorporation of Ebola GP into VLPs was demonstrated by SDS-PAGE and Western blot analysis. Recombinant baculovirus infection of insect cells yielded high levels of VLPs, which were shown to stimulate cytokine secretion from human dendritic cells similar to VLPs produced in mammalian cells. The immunogenicity of Ebola VLPs produced in insect cells was evaluated by immunization of mice. Analysis of antibody responses showed that most of the GP-specific antibodies were of the IgG2a subtype, while no significant level of IgG1 subtype antibodies specific for GP was induced, indicating the induction of a Th1-biased immune response. Furthermore, sera from Ebola VLP immunized mice were able to block infection by Ebola GP pseudotyped HIV virus in a single round infection assay, indicating that a neutralizing antibody against the Ebola GP protein was induced. These results show that production of Ebola VLPs in insect cells using recombinant baculoviruses represents a promising approach for vaccine development against Ebola virus infection

  9. Identification and characterization of a virus-specific continuous B-cell epitope on the PrM/M protein of Japanese Encephalitis Virus: potential application in the detection of antibodies to distinguish Japanese Encephalitis Virus infection from West Nile Virus and Dengue Virus infections

    OpenAIRE

    Hua, Rong-Hong; Chen, Na-Sha; Qin, Cheng-Feng; Deng, Yong-Qiang; Ge, Jin-Ying; Wang, Xi-Jun; Qiao, Zu-Jian; Chen, Wei-Ye; Wen, Zhi-Yuan; Liu, Wen-Xin; Hu, Sen; Bu, Zhi-Gao

    2010-01-01

    Abstract Background Differential diagnose of Japanese encephalitis virus (JEV) infection from other flavivirus especially West Nile virus (WNV) and Dengue virus (DV) infection was greatly hindered for the serological cross-reactive. Virus specific epitopes could benefit for developing JEV specific antibodies detection methods. To identify the JEV specific epitopes, we fully mapped and characterized the continuous B-cell epitope of the PrM/M protein of JEV. Results To map the epitopes on the P...

  10. Gag- and env-specific serum antibodies in cats after natural and experimental infection with feline immunodeficiency virus.

    NARCIS (Netherlands)

    G.F. Rimmelzwaan (Guus); C.H.J. Siebelink (Kees); H. Broos; G.A. Drost; K. Weijer (Kees); R. van Herwijnen (Rob); A.D.M.E. Osterhaus (Albert)

    1994-01-01

    textabstractIn order to monitor the antibody response to feline immunodeficiency virus (FIV) in cats, following experimental and natural infection, enzyme-linked immunosorbent assays (ELISAs) were developed using recombinant env and gag proteins and p24-specific monoclonal antibodies. It was shown

  11. Modulation of the virus-receptor interaction by mutations in the V5 loop of feline immunodeficiency virus (FIV following in vivo escape from neutralising antibody

    Directory of Open Access Journals (Sweden)

    Samman Ayman

    2010-04-01

    Full Text Available Abstract Background In the acute phase of infection with feline immunodeficiency virus (FIV, the virus targets activated CD4+ T cells by utilising CD134 (OX40 as a primary attachment receptor and CXCR4 as a co-receptor. The nature of the virus-receptor interaction varies between isolates; strains such as GL8 and CPGammer recognise a "complex" determinant on CD134 formed by cysteine-rich domains (CRDs 1 and 2 of the molecule while strains such as PPR and B2542 require a more "simple" determinant comprising CRD1 only for infection. These differences in receptor recognition manifest as variations in sensitivity to receptor antagonists. In this study, we ask whether the nature of the virus-receptor interaction evolves in vivo. Results Following infection with a homogeneous viral population derived from a pathogenic molecular clone, a quasispecies emerged comprising variants with distinct sensitivities to neutralising antibody and displaying evidence of conversion from a "complex" to a "simple" interaction with CD134. Escape from neutralising antibody was mediated primarily by length and sequence polymorphisms in the V5 region of Env, and these alterations in V5 modulated the virus-receptor interaction as indicated by altered sensitivities to antagonism by both anti-CD134 antibody and soluble CD134. Conclusions The FIV-receptor interaction evolves under the selective pressure of the host humoral immune response, and the V5 loop contributes to the virus-receptor interaction. Our data are consistent with a model whereby viruses with distinct biological properties are present in early versus late infection and with a shift from a "complex" to a "simple" interaction with CD134 with time post-infection.

  12. Modulation of the virus-receptor interaction by mutations in the V5 loop of feline immunodeficiency virus (FIV) following in vivo escape from neutralising antibody.

    Science.gov (United States)

    Willett, Brian J; Kraase, Martin; Logan, Nicola; McMonagle, Elizabeth L; Samman, Ayman; Hosie, Margaret J

    2010-04-26

    In the acute phase of infection with feline immunodeficiency virus (FIV), the virus targets activated CD4+ T cells by utilising CD134 (OX40) as a primary attachment receptor and CXCR4 as a co-receptor. The nature of the virus-receptor interaction varies between isolates; strains such as GL8 and CPGammer recognise a "complex" determinant on CD134 formed by cysteine-rich domains (CRDs) 1 and 2 of the molecule while strains such as PPR and B2542 require a more "simple" determinant comprising CRD1 only for infection. These differences in receptor recognition manifest as variations in sensitivity to receptor antagonists. In this study, we ask whether the nature of the virus-receptor interaction evolves in vivo. Following infection with a homogeneous viral population derived from a pathogenic molecular clone, a quasispecies emerged comprising variants with distinct sensitivities to neutralising antibody and displaying evidence of conversion from a "complex" to a "simple" interaction with CD134. Escape from neutralising antibody was mediated primarily by length and sequence polymorphisms in the V5 region of Env, and these alterations in V5 modulated the virus-receptor interaction as indicated by altered sensitivities to antagonism by both anti-CD134 antibody and soluble CD134. The FIV-receptor interaction evolves under the selective pressure of the host humoral immune response, and the V5 loop contributes to the virus-receptor interaction. Our data are consistent with a model whereby viruses with distinct biological properties are present in early versus late infection and with a shift from a "complex" to a "simple" interaction with CD134 with time post-infection.

  13. Serum-dependent expression of promyelocytic leukemia protein suppresses propagation of influenza virus

    International Nuclear Information System (INIS)

    Iki, Shigeo; Yokota, Shin-ichi; Okabayashi, Tamaki; Yokosawa, Noriko; Nagata, Kyosuke; Fujii, Nobuhiro

    2005-01-01

    The rate of propagation of influenza virus in human adenocarcinoma Caco-2 cells was found to negatively correlate with the concentration of fetal bovine serum (FBS) in the culture medium. Virus replicated more rapidly at lower FBS concentrations (0 or 2%) than at higher concentrations (10 or 20%) during an early stage of infection. Basal and interferon (IFN)-induced levels of typical IFN-inducible anti-viral proteins, such as 2',5'-oligoadenylate synthetase, dsRNA-activated protein kinase and MxA, were unaffected by variation in FBS concentrations. But promyelocytic leukemia protein (PML) was expressed in a serum-dependent manner. In particular, the 65 to 70 kDa isoform of PML was markedly upregulated following the addition of serum. In contrast, other isoforms were induced by IFN treatment, and weakly induced by FBS concentrations. Immunofluorescence microscopy indicated that PML was mainly formed nuclear bodies in Caco-2 cells at various FBS concentrations, and the levels of the PML-nuclear bodies were upregulated by FBS. Overexpression of PML isoform consisting of 560 or 633 amino acid residues by transfection of expression plasmid results in significantly delayed viral replication rate in Caco-2 cells. On the other hand, downregulation of PML expression by RNAi enhanced viral replication. These results indicate that PML isoforms which are expressed in a serum-dependent manner suppress the propagation of influenza virus at an early stage of infection

  14. Diagnostic significance of DNA and antibodies against capsid antigens of anti-Epstein–Barr virus antibodies levels in blood plasma of nasopharyngeal carcinoma patients from non-endemic region

    Directory of Open Access Journals (Sweden)

    V. E. Gurtsevich

    2015-01-01

    Full Text Available Epstein–Barr virus (EBV, a representative of the herpesvirus family, is the etiological agent for a number of benign and malignant human neoplasms. Among the latter, the nasopharyngeal carcinoma (NPC occupies a special place. In NPC development EBV plays a key role stimulating the progression of the pathological process from precancerous lesions to the cancer development. For most NPC patients, elevated levels of humoral IgG and IgA antibodies against capsid and early EBV antigens are characteristic and their antibody titers rise to high levels long before the diagnosis of cancer. Using this phenomenon, virus-specific antibodies are used for many years as markers for NPC screening, especially in cases of undiagnosed primary lesion. In recent years, in endemic for NPC regions (South China, South-East Asia a great attention has been paid to the use of quantitative determination of EBV DNA copies in the blood plasma of patients with NPC as a method of early cancer detection and monitoring.The aim of this study was to compare clinical significance of EBV DNA and humoral antibodies levels in blood plasma of NPC patients in non-endemic region, Russia. The results obtained indicate that both markers DNA / EBV and IgA antibodies against capsid EBV antigens can be successfully used for diagnosis of NPC in non-endemic region. However, in comparison with the virus-specific antibody titers, the viral DNA levels in the patients plasma are more sensitive and specific as NPC marker reflecting the efficacy of the therapy, and the state of remission or relapse.

  15. Identification of a High Affinity Nucleocapsid Protein Binding Element from The Bovine Leukemia Virus Genome

    Science.gov (United States)

    Yildiz, F. Zehra; Babalola, Kathleen; Summers, Michael F.

    2012-01-01

    Retroviral genome recognition is mediated by interactions between the nucleocapsid (NC) domain of the virally encoded Gag polyprotein and cognate RNA packaging elements that, for most retroviruses, appear to reside primarily within the 5′-untranslated region (5′-UTR) of the genome. Recent studies suggest that a major packaging determinant of Bovine Leukemia Virus (BLV), a member of the human T-cell leukemia virus (HTLV)/BLV family and a non-primate animal model for HTLV-induced leukemogenesis, resides within the gag open reading frame. We have prepared and purified the recombinant BLV NC protein and conducted electrophoretic mobility shift and isothermal titration calorimetry studies with RNA fragments corresponding to these proposed packaging elements. The gag-derived RNAs did not exhibit significant affinity for NC, suggesting an alternate role in packaging. However, an 83-nucleotide fragment of the 5′-UTR that resides just upstream of the gag start codon binds NC stoichiometrically and with high affinity (Kd = 136 ± 21 nM). These nucleotides were predicted to form tandem hairpin structures, and studies with smaller fragments indicate that the NC binding site resides exclusively within the distal hairpin (residues G369- U399, Kd = 67 ± 8 nM at physiological ionic strength). Unlike all other structurally characterized retroviral NC binding RNAs, this fragment is not expected to contain exposed guanosines, suggesting that RNA binding may be mediated by a previously uncharacterized mechanism. PMID:22846919

  16. Late radiation effects of low doses from occupational exposure. Antibodies to cytomegalovirus, Epstein-Barr virus and human T cell lymphotropic virus type 1 in radiological technologists

    Energy Technology Data Exchange (ETDEWEB)

    Kumagai, Etsuko; Tanoue, Shozo (Kumamoto Univ. (Japan). Coll. of Medical Science); Sawada, Shozo

    1989-05-01

    To elucidate the effects of long-term exposure to low dose irradiation, serostatus of antibodies to cytomegalovirus (CMV), Epstein-Barr virus (EBV) and human T cell lymphotropic virus type 1 (HTLV-1) was determined in 99 radiological technologists and 96 healthy volunteers. Abnormal seropositivity rate for CMV was significantly higher in technologists working for 15 years or more than in those working for less than 15 years. For the same age group, however, there was no significant difference between technologists and controls. Seropositivity rates for EBV-viral capsid antigen (VSA)/IgG and early antigen (EA)/IgG were significantly higher in technologists working for 15 years or more than in the age-matched control group. In the group of technologists exposed to 0.3 Sv or more, seropositivity rates of these antibodies were significantly higher than in those exposed to less than 0.3 Sv. However, there was no correlation between exposure doses and both EBV-associated nuclear antigen antibody and HTLV-1 antibody. Few technologists seronegative for CMV antibody had seropositive antibodies of EBV-VCA/IgG and EA/IgG. For technologists seropositive for CMV antibody, 31% and 54% were seropositive for EBV-VCA/IgG and EA/IgG antibodies, respectively. (Namekawa, K).

  17. Production of Polyclonal Antibodies to Potato virus X Using Recombinant Coat Protein

    Czech Academy of Sciences Publication Activity Database

    Čeřovská, Noemi; Moravec, Tomáš; Plchová, Helena; Hoffmeisterová, Hana; Kmoníčková, Jitka; Dědič, P.

    2010-01-01

    Roč. 158, č. 1 (2010), s. 66-68 ISSN 0931-1785 R&D Projects: GA MŠk 1M06030 Institutional research plan: CEZ:AV0Z50380511 Keywords : Potato virus X * recombinant viral antigen * antibodies Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.937, year: 2010

  18. Detection of hepatitis B virus infection in HBsAg-negative patients by monoclonal antibodies against HBsAg

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, Y K

    1986-11-01

    The technique of producing antibody secreting hybridomas has made available high-affinity antibodies of predefined specificity for use as diagnostic reagents. Recently, high-affinity monoclonal antibodies to hepatitis B surface antigens (HBsAg) were produced and characterized. Immunoassay was developed using these antibodies for the detection of HBsAg-associated determinants. The present study indicated the significance of the enhanced detection by monoclonal radioimmunoassay (M-RIA) of HBsAg in sera of patients with hepatitis B virus infection. The M-RIA detected HBsAg in sera of hemodialysis patients and blood donor defined as HBsAg-negative by polyclonal RIA (2.2 %, 0.14 %, respectively). Furthermore, individuals with chronic liver diseases were reactive only in the M-RIA (chronic hepatitis 4.8 %, liver cirrhosis 10.0 %, hepatocellular carcinoma 22.2 %). It is noteworthy that some of these patients were diagnosesed as so-called non-A non-B hepatitis because of no serological markers of hepatitis B virus infection such as HBsAb and HBcAb. The enhanced performance of the monoclonal RIA compared to conventional RIA was due to the increased sensitivity of the assay (55 pg vs 230 pg/ml). In immunohistochemical study, one of the monoclonal antibody named 5C3 was applied for detection of HBsAg in the formalin-fixed paraffin-embedded liver. HBsAg was detected in 6 out of 41 HBsAg-seronegative liver specimen. Thus, the studies showed the importance of the clinical application of monoclonal antibodies such as immunoassay and immunohistochemical study in the diagnosis of hepatitis B virus infection.

  19. Detection of hepatitis B virus infection in HBsAg-negative patients by monoclonal antibodies against HBsAg

    International Nuclear Information System (INIS)

    Fujita, Y.K.

    1986-01-01

    The technique of producing antibody secreting hybridomas has made available high-affinity antibodies of predefined specificity for use as diagnostic reagents. Recently, high-affinity monoclonal antibodies to hepatitis B surface antigens (HBsAg) were produced and characterized. Immunoassay was developed using these antibodies for the detection of HBsAg-associated determinants. The present study indicated the significance of the enhanced detection by monoclonal radioimmunoassay (M-RIA) of HBsAg in sera of patients with hepatitis B virus infection. The M-RIA detected HBsAg in sera of hemodialysis patients and blood donor defined as HBsAg-negative by polyclonal RIA (2.2 %, 0.14 %, respectively). Furthermore, individuals with chronic liver diseases were reactive only in the M-RIA (chronic hepatitis 4.8 %, liver cirrhosis 10.0 %, hepatocellular carcinoma 22.2 %). It is noteworthy that some of these patients were diagnosesed as so-called non-A non-B hepatitis because of no serological markers of hepatitis B virus infection such as HBsAb and HBcAb. The enhanced performance of the monoclonal RIA compared to conventional RIA was due to the increased sensitivity of the assay (55 pg vs 230 pg/ml). In immunohistochemical study, one of the monoclonal antibody named 5C3 was applied for detection of HBsAg in the formalin-fixed paraffin-embedded liver. HBsAg was detected in 6 out of 41 HBsAg-seronegative liver specimen. Thus, the studies showed the importance of the clinical application of monoclonal antibodies such as immunoassay and immunohistochemical study in the diagnosis of hepatitis B virus infection. (author)

  20. Validation of the rapid fluorescent focus inhibition test for rabies virus-neutralizing antibodies in clinical samples

    NARCIS (Netherlands)

    Kostense, Stefan; Moore, Susan; Companjen, Arjen; Bakker, Alexander B. H.; Marissen, Wilfred E.; von Eyben, Rie; Weverling, Gerrit Jan; Hanlon, Cathleen; Goudsmit, Jaap

    2012-01-01

    Monoclonal antibodies are successful biologics in treating a variety of diseases, including the prevention or treatment of viral infections. CL184 is a 1:1 combination of two human monoclonal IgG1 antibodies (CR57 and CR4098) against rabies virus, produced in the PER.C6 human cell line. The two

  1. Dengue virus infection-enhancing antibody activities against Indonesian strains in inhabitants of central Thailand.

    Science.gov (United States)

    Yamanaka, Atsushi; Oddgun, Duangjai; Chantawat, Nantarat; Okabayashi, Tamaki; Ramasoota, Pongrama; Churrotin, Siti; Kotaki, Tomohiro; Kameoka, Masanori; Soegijanto, Soegeng; Konishi, Eiji

    2016-04-01

    Dengue virus (DENV) infection-enhancing antibodies are a hypothetic factor to increase the dengue disease severity. In this study, we investigated the enhancing antibodies against Indonesian strains of DENV-1-4 in 50 healthy inhabitants of central Thailand (Bangkok and Uthai Thani). Indonesia and Thailand have seen the highest dengue incidence in Southeast Asia. The infection history of each subject was estimated by comparing his/her neutralizing antibody titers against prototype DENV-1-4 strains. To resolve the difficulty in obtaining foreign live viruses for use as assay antigens, we used a recombinant system to prepare single-round infectious dengue viral particles based on viral sequence information. Irrespective of the previously infecting serotype(s), most serum samples showed significantly higher enhancement titers against Indonesian DENV-2 strains than against Thai DENV-2 strains, whereas the opposite effect was observed for the DENV-3 strains. Equivalent enhancing activities were observed against both DENV-1 and DENV-4. These results suggest that the genotype has an impact on enhancing antibody activities against DENV-2 and DENV-3, because the predominant circulating genotypes of each serotype differ between Indonesia and Thailand. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  2. Rabies direct fluorescent antibody test does not inactivate rabies or eastern equine encephalitis viruses.

    Science.gov (United States)

    Jarvis, Jodie A; Franke, Mary A; Davis, April D

    2016-08-01

    An examination using the routine rabies direct fluorescent antibody test was performed on rabies or Eastern equine encephalitis positive mammalian brain tissue to assess inactivation of the virus. Neither virus was inactivated with acetone fixation nor the routine test, thus laboratory employees should treat all samples as rabies and when appropriate Eastern equine encephalitis positive throughout the whole procedure. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Integration of antibody by surface functionalization of graphite-encapsulated magnetic beads using ammonia gas plasma technology for capturing influenza A virus.

    Science.gov (United States)

    Sakudo, Akikazu; Chou, Han; Ikuta, Kazuyoshi; Nagatsu, Masaaki

    2015-05-01

    Antibody-integrated magnetic beads have been functionalized for influenza A virus capture. First, ammonia plasma produced by a radio frequency power source was reacted with the surface of graphite-encapsulated magnetic beads to introduce amino groups. Anti-influenza A virus hemagglutinin antibody was then anchored by its surface sulfide groups to the amino groups on the beads via N-succinimidyl 3-(2-pyridyldithio) propionate. After incubation with influenza A virus, adsorption of the virus to the beads was confirmed by immunochromatography, polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA), and inoculation of chicken embryonated eggs, indicating that virus infectivity is maintained and that the proposed method is useful for the enhanced detection and isolation of influenza A virus. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Development and evaluation of a competitive ELISA using a monoclonal antibody for antibody detection after goose parvovirus virus-like particles (VLPs) and vaccine immunization in goose sera.

    Science.gov (United States)

    Wang, Qian; Ju, Huanyu; Li, Yanwei; Jing, Zhiqiang; Guo, Lu; Zhao, Yu; Ma, Bo; Gao, Mingchun; Zhang, Wenlong; Wang, Junwei

    2014-12-01

    An assay protocol based on a monoclonal antibody-based competitive enzyme-linked immunosorbent assay (MAb-based C-ELISA) for detecting antibodies against goose parvovirus (GPV) and its virus-like particles (VLPs) is described. The assay was developed using baculovirus-expressed recombinant VP2 virus-like particles (rVP2-VLPs) as antigens and a monoclonal antibody against GPV as the competitive antibody. Of the four anti-GPV MAbs that were screened, MAb 1G3 was selected as it was blocked by the GPV positive serum. Based on the distribution of percent inhibition (PI) of the known negative sera (n=225), a cut-off value was set at 36% inhibition. Using this cut-off value, the sensitivity of the assay was 93.3% and the specificity was 95.8%, as compared with the gold standard (virus neutralization assay). The rVP2-VLPs did not react with anti-sera to other goose pathogens, indicating that it is specific for the recognization of goose parvovirus antibodies. The assay was then validated with serum samples from goslings vaccinated with several VLPs (rVP1-VLPs, rVP2-VLPs, rVP3-VLPs, and rCGV-VLPs) and other vaccines (inactivated and attenuated). The C-ELISA described in this study is a sensitive and specific diagnostic test and should have wide applications for the sero-diagnosis and immunologic surveillance of GPV. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Prevalence Estimates of Antibodies Towards Foot-and-Mouth Disease Virus in Small Ruminants in Uganda

    DEFF Research Database (Denmark)

    Balinda, Sheila Nina; Tjørnehøj, Kirsten; Muwanika, Vincent B.

    2009-01-01

    summarizes results of serological investigations of sheep and goats for antibodies to FMDV from four districts in 2006 following an FMD outbreak in the region and from an attempted comprehensive random sampling in two districts in 2007. Antibodies were quantified and serotyped using competitive ELISA...... for antibodies towards non-structural proteins (NSP) and structural proteins towards serotype O, and blocking ELISA for antibodies towards the seven serotypes of FMD virus (FMDV). In 2006, sheep and goats in Bushenyi and Isingiro districts were free from antibodies towards FMDV, while herds in Kasese and Mbarara...... districts excluding Kahendero village were all positive for antibodies towards NSP and SP-O. In 2007, mean prevalence estimates of antibodies towards FMDV NSP was 14% in goats and 22% in sheep in Kasese district, while Bushenyi was still free. The difference between these two districts probably reflects...

  6. Antibodies against severe fever with Thrombocytopenia syndrome Virus in healthy persons, China, 2013

    NARCIS (Netherlands)

    Zhang Lei, Lei; Sun, J.; Yan, J.; Huakun, L.; Chai, C.Y.; Sun, Y.; Shao, B.; Jiang, J.D.; Chen, Z.; Kortekaas, J.A.; Zhang, Y.

    2014-01-01

    In June 2013, a subclinical infection with severe fever with thrombocytopenia syndrome virus (SFTSV) was detected in Zhejiang Province, China, prompting seroprevalence studies in 6 districts within the province. Of 986 healthy persons tested, 71 had IgG antibodies against SFTSV. This finding

  7. Anti-N-methyl-D-aspartate receptor encephalitis with serum anti-thyroid antibodies and IgM antibodies against Epstein-Barr virus viral capsid antigen: a case report and one year follow-up

    Directory of Open Access Journals (Sweden)

    Xu Chun-Ling

    2011-11-01

    Full Text Available Abstract Background Anti-N-methyl-D-aspartate receptor encephalitis is an increasingly common autoimmune disorder mediated by antibodies to certain subunit of the N-methyl-D-aspartate receptor. Recent literatures have described anti-thyroid and infectious serology in this encephalitis but without follow-up. Case presentation A 17-year-old Chinese female patient presented with psychiatric symptoms, memory deficits, behavioral problems and seizures. She then progressed through unresponsiveness, dyskinesias, autonomic instability and central hypoventilation during treatment. Her conventional blood work on admission showed high titers of IgG antibodies to thyroglobulin, thyroid peroxidase and IgM antibodies to Epstein-Barr virus viral capsid antigen. An immature ovarian teratoma was found and removal of the tumor resulted in a full recovery. The final diagnosis of anti-N-methyl-D-aspartate receptor encephalitis was made by the identification of anti-N-methyl-D-aspartate receptor antibodies in her cerebral spinal fluid. Pathology studies of the teratoma revealed N-methyl-D-aspartate receptor subunit 1 positive ectopic immature nervous tissue and Epstein-Barr virus latent infection. She was discharged with symptoms free, but titers of anti-thyroid peroxidase and anti-thyroglobulin antibodies remained elevated. One year after discharge, her serum remained positive for anti-thyroid peroxidase and anti-N-methyl-D-aspartate receptor antibodies, but negative for anti-thyroglobulin antibodies and IgM against Epstein-Barr virus viral capsid antigen. Conclusions Persistent high titers of anti-thyroid peroxidase antibodies from admission to discharge and until one year later in this patient may suggest a propensity to autoimmunity in anti- N-methyl-D-aspartate receptor encephalitis and support the idea that neuronal and thyroid autoimmunities represent a pathogenic spectrum. Enduring anti-N-methyl-D-aspartate receptor antibodies from admission to one year

  8. Viral diagnostic criteria for Feline immunodeficiency virus and Feline leukemia virus infections in domestic cats from Buenos Aires, Argentina.

    Science.gov (United States)

    Galdo Novo, Sabrina; Bucafusco, Danilo; Diaz, Leandro M; Bratanich, Ana Cristina

    A cross-sectional study was carried out on cats attending the Small Animal Hospital at the Faculty of Veterinary Sciences of the University of Buenos Aires to assess the prevalence and associated risk factors of Feline immunodeficiency virus (FIV) and Feline leukemia virus (FeLV) in the city of Buenos Aires, Argentina. Blood samples from 255 cats with symptoms compatible with FIV or FeLV infection, collected between 2009 and 2013 were analyzed by serology (immunochromatography, IA) and by hemi-nested PCR (n-PCR). The IA and n-PCR assays showed similar percentages of positivity for FIV while the n-PCR test was more sensitive for FeLV. Differences between the diagnostic tests and their choice according to the age of the animal are discussed. The clinical histories of ninety of the 255 cats showed blood profiles similar to others previously reported and revealed a higher risk of infection in male adult cats with outdoor access. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  9. Epitopes on the peplomer protein of infectious bronchitis virus strain M41 as defined by monoclonal antibodies.

    NARCIS (Netherlands)

    N.M.C. Bleumink-Pluym; A.D.M.E. Osterhaus (Albert); M.C. Horzinek; B.A.M. van der Zeijst (Ben); H.G.M. Niesters (Bert)

    1987-01-01

    textabstractSixteen monoclonal antibodies (Mcabs) were prepared against infectious bronchitis virus strain M41, all of them reacting with the peplomer protein. One of them, Mcab 13, was able to neutralize the virus and to inhibit hemagglutination. Competition binding assays allowed the definition of

  10. Detection of Anti-Asparaginase Antibodies During Therapy with E.coli Asparaginase in Children with Newly Diagnosed Acute Lymphoblastic Leukemia and Lymphoma

    International Nuclear Information System (INIS)

    EBEID, E.N.; KAMEL, M.M.; ALI, B.A.

    2008-01-01

    Background: Asparaginase is an effective anti leukemic agent which is included in most front-line protocols for pediatric acute lymphoblastic leukemia (All) worldwide. Since asparaginase is a bacterial protein, it may induce formation of antibodies. The reported frequency of anti-asparaginase antibodies is highly variable: antibodies have been reported in as many as 79% of adults and as many as 70% of children after intravenous or intramuscular administration of E.coli asparaginase. Purpose: The aim of this study was to determine if the presence of antibodies during induction and continuation phases in newly diagnosed children with ALL and lymphoblastic lymphoma during therapy with E.coli asparaginase, had any correlation with various factors such as: age, gender, hypersensitivity reactions, response to therapy and Event Free Survival (EFS). Patients and Methods: Between the period from March 2005 to May 2007, sixty-four children who attended the Menia outpatient pediatric oncology clinic, or were admitted to the in patient department of the Menia oncology center, were enrolled in the study. Forty children had newly diagnosed ALL and 24 had lymphoblastic lymphoma. Patients were 48 males (75%) and 16 females (25%) with a male:female ratio 3:1. Their ages ranged from 3.5 to 17 years with mean age of 9.6 years. All patients received asparaginase therapy according to the St. Jude Total X III protocol, in a dose of 10,000 Iu/m2/dose, intramuscularly for 6-9 doses during the induction phase and another 6-9 doses during continuation phase according to disease status. Results: Forty one patients achieved complete remission, 9 had partial remission, and 14 were lost to followup at different intervals of treatment. Anti asparaginase antibodies were detected in 36 patients (56%) out of 64 patients, and 37 patients (60%) out of 62 patients who were treated with asparaginase at day 8 and day 27 of induction phase respectively. Moreover, 33 patients (61%) out of 54 patients, and

  11. ''reverse'' solid-phase radioimmunoasssay for IgM-antibodies to hepatitis A virus

    Energy Technology Data Exchange (ETDEWEB)

    Meurman, O H; Matter, L; Krishna, R V; Krech, U H [Institute of Medical Microbiology, St. Gallen, Switzerland

    1981-01-01

    A ''reverse'' solid-phase radio-immuno-assay for IgM antibodies to hepatitis A virus (HAV) was developed. Anti-human IgM immunoglobulins were bound on the wells of polyvinylchloride microtiter plates. Serum specimens were incubated in the anti-human IgM coated wells and bound IgM antibodies were then assayed for antigen specificity by subsequent incubations with HAV antigen and /sup 125/I-labelled human anti-HAV IgG. The test showed a high sensitivity and specificity for anti-HAV IgM antibodies. No false-positive reactions were observed either in the sera from patients with hepatobiliary disorders other than HAV infection or in the sera containing both rheumatoid factor and anti-HAV IgG antibodies. In acute HAV infections specific IgM antibodies were present already in the first specimens taken within a few days after the onset of jaundice. The persistence of the IgM antibodies was from 4 to 6 months. IgM antibody titers up to 1,000,000 were observed in the acute phase of HAV infection. In routine diagnostic work the titration of the sera was not necessary, since a reliable qualitative result was obtained by testing the sera in a single dilution of 1:100. A similar reverse immuno-assay principle may be adaptable for the diagnostic determination of IgM antibodies to different viral and microbial antigens.

  12. Seroprevalences of feline leukemia virus and feline immunodeficiency virus infection in cats in the United States and Canada and risk factors for seropositivity.

    Science.gov (United States)

    Burling, Amie N; Levy, Julie K; Scott, H Morgan; Crandall, Michael M; Tucker, Sylvia J; Wood, Erin G; Foster, Jessie D

    2017-07-15

    OBJECTIVE To estimate seroprevalences for FeLV antigen and anti-FIV antibody and risk factors for seropositivity among cats in the United States and Canada. DESIGN Cross-sectional study. ANIMALS 62,301 cats tested at 1,396 veterinary clinics (n = 45,406) and 127 animal shelters (16,895). PROCEDURES Blood samples were tested with a point-of-care ELISA for FeLV antigen and anti-FIV antibody. Seroprevalence was estimated, and risk factors for seropositivity were evaluated with bivariate and multivariable mixed-model logistic regression analyses adjusted for within-clinic or within-shelter dependencies. RESULTS Overall, seroprevalence was 3.1% for FeLV antigen and 3.6% for anti-FIV antibody. Adult age, outdoor access, clinical disease, and being a sexually intact male were risk factors for seropositivity for each virus. Odds of seropositivity for each virus were greater for cats tested in clinics than for those tested in shelters. Of 1,611 cats with oral disease, 76 (4.7%) and 157 (9.7%) were seropositive for FeLV and FIV, respectively. Of 4,835 cats with respiratory disease, 385 (8.0%) were seropositive for FeLV and 308 (6.4%) were seropositive for FIV. Of 1,983 cats with abscesses or bite wounds, 110 (5.5%) and 247 (12.5%) were seropositive for FeLV and FIV, respectively. Overall, 2,368 of 17,041 (13.9%) unhealthy cats were seropositive for either or both viruses, compared with 1,621 of 45,260 (3.6%) healthy cats. CONCLUSIONS AND CLINICAL RELEVANCE Seroprevalences for FeLV antigen and anti-FIV antibody were similar to those reported in previous studies over the past decade. Taken together, these results indicated a need to improve compliance with existing guidelines for management of feline retroviruses.

  13. Genome-wide association study for host response to bovine leukemia virus in Holstein cows.

    Science.gov (United States)

    Brym, P; Bojarojć-Nosowicz, B; Oleński, K; Hering, D M; Ruść, A; Kaczmarczyk, E; Kamiński, S

    2016-07-01

    The mechanisms of leukemogenesis induced by bovine leukemia virus (BLV) and the processes underlying the phenomenon of differential host response to BLV infection still remain poorly understood. The aim of the study was to screen the entire cattle genome to identify markers and candidate genes that might be involved in host response to bovine leukemia virus infection. A genome-wide association study was performed using Holstein cows naturally infected by BLV. A data set included 43 cows (BLV positive) and 30 cows (BLV negative) genotyped for 54,609 SNP markers (Illumina Bovine SNP50 BeadChip). The BLV status of cows was determined by serum ELISA, nested-PCR and hematological counts. Linear Regression Analysis with a False Discovery Rate and kinship matrix (computed on the autosomal SNPs) was calculated to find out which SNP markers significantly differentiate BLV-positive and BLV-negative cows. Nine markers reached genome-wide significance. The most significant SNPs were located on chromosomes 23 (rs41583098), 3 (rs109405425, rs110785500) and 8 (rs43564499) in close vicinity of a patatin-like phospholipase domain containing 1 (PNPLA1); adaptor-related protein complex 4, beta 1 subunit (AP4B1); tripartite motif-containing 45 (TRIM45) and cell division cycle associated 2 (CDCA2) genes, respectively. Furthermore, a list of 41 candidate genes was composed based on their proximity to significant markers (within a distance of ca. 1 Mb) and functional involvement in processes potentially underlying BLV-induced pathogenesis. In conclusion, it was demonstrated that host response to BLV infection involves nine sub-regions of the cattle genome (represented by 9 SNP markers), containing many genes which, based on the literature, could be involved to enzootic bovine leukemia progression. New group of promising candidate genes associated with the host response to BLV infection were identified and could therefore be a target for future studies. The functions of candidate genes

  14. Structural basis for the antibody neutralization of Herpes simplex virus

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Cheng-Chung; Lin, Li-Ling [Academia Sinica, Taipei 115, Taiwan (China); Academia Sinica, Taipei 115, Taiwan (China); Chan, Woan-Eng [Development Center for Biotechnology, New Taipei City 221, Taiwan (China); Ko, Tzu-Ping [Academia Sinica, Taipei 115, Taiwan (China); Academia Sinica, Taipei 115, Taiwan (China); Lai, Jiann-Shiun [Development Center for Biotechnology, New Taipei City 221, Taiwan (China); Ministry of Economic Affairs, Taipei 100, Taiwan (China); Wang, Andrew H.-J., E-mail: ahjwang@gate.sinica.edu.tw [Academia Sinica, Taipei 115, Taiwan (China); Academia Sinica, Taipei 115, Taiwan (China); Taipei Medical University, Taipei 110, Taiwan (China)

    2013-10-01

    The gD–E317-Fab complex crystal revealed the conformational epitope of human mAb E317 on HSV gD, providing a molecular basis for understanding the viral neutralization mechanism. Glycoprotein D (gD) of Herpes simplex virus (HSV) binds to a host cell surface receptor, which is required to trigger membrane fusion for virion entry into the host cell. gD has become a validated anti-HSV target for therapeutic antibody development. The highly inhibitory human monoclonal antibody E317 (mAb E317) was previously raised against HSV gD for viral neutralization. To understand the structural basis of antibody neutralization, crystals of the gD ectodomain bound to the E317 Fab domain were obtained. The structure of the complex reveals that E317 interacts with gD mainly through the heavy chain, which covers a large area for epitope recognition on gD, with a flexible N-terminal and C-terminal conformation. The epitope core structure maps to the external surface of gD, corresponding to the binding sites of two receptors, herpesvirus entry mediator (HVEM) and nectin-1, which mediate HSV infection. E317 directly recognizes the gD–nectin-1 interface and occludes the HVEM contact site of gD to block its binding to either receptor. The binding of E317 to gD also prohibits the formation of the N-terminal hairpin of gD for HVEM recognition. The major E317-binding site on gD overlaps with either the nectin-1-binding residues or the neutralizing antigenic sites identified thus far (Tyr38, Asp215, Arg222 and Phe223). The epitopes of gD for E317 binding are highly conserved between two types of human herpesvirus (HSV-1 and HSV-2). This study enables the virus-neutralizing epitopes to be correlated with the receptor-binding regions. The results further strengthen the previously demonstrated therapeutic and diagnostic potential of the E317 antibody.

  15. Antibodies to a strain-specific citrullinated Epstein-Barr virus peptide diagnoses rheumatoid arthritis

    DEFF Research Database (Denmark)

    Trier, Nicole Hartwig; Holm, Bettina Eide; Heiden, Julie

    2018-01-01

    Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease. Anti-citrullinated protein antibodies (ACPA) are crucial for the serological diagnosis of RA, where Epstein-Barr virus (EBV) has been suggested to be an environmental agent in triggering the onset of the disease. This study aimed...

  16. Generation of Recombinant Porcine Parvovirus Virus-Like Particles in Saccharomyces cerevisiae and Development of Virus-Specific Monoclonal Antibodies

    Directory of Open Access Journals (Sweden)

    Paulius Lukas Tamošiūnas

    2014-01-01

    Full Text Available Porcine parvovirus (PPV is a widespread infectious virus that causes serious reproductive diseases of swine and death of piglets. The gene coding for the major capsid protein VP2 of PPV was amplified using viral nucleic acid extract from swine serum and inserted into yeast Saccharomyces cerevisiae expression plasmid. Recombinant PPV VP2 protein was efficiently expressed in yeast and purified using density gradient centrifugation. Electron microscopy analysis of purified PPV VP2 protein revealed the self-assembly of virus-like particles (VLPs. Nine monoclonal antibodies (MAbs against the recombinant PPV VP2 protein were generated. The specificity of the newly generated MAbs was proven by immunofluorescence analysis of PPV-infected cells. Indirect IgG ELISA based on the recombinant VLPs for detection of PPV-specific antibodies in swine sera was developed and evaluated. The sensitivity and specificity of the new assay were found to be 93.4% and 97.4%, respectively. In conclusion, yeast S. cerevisiae represents a promising expression system for generating recombinant PPV VP2 protein VLPs of diagnostic relevance.

  17. Insertional Polymorphisms of Endogenous Feline Leukemia Viruses

    Science.gov (United States)

    Roca, Alfred L.; Nash, William G.; Menninger, Joan C.; Murphy, William J.; O'Brien, Stephen J.

    2005-01-01

    The number, chromosomal distribution, and insertional polymorphisms of endogenous feline leukemia viruses (enFeLVs) were determined in four domestic cats (Burmese, Egyptian Mau, Persian, and nonbreed) using fluorescent in situ hybridization and radiation hybrid mapping. Twenty-nine distinct enFeLV loci were detected across 12 of the 18 autosomes. Each cat carried enFeLV at only 9 to 16 of the loci, and many loci were heterozygous for presence of the provirus. Thus, an average of 19 autosomal copies of enFeLV were present per cat diploid genome. Only five of the autosomal enFeLV sites were present in all four cats, and at only one autosomal locus, B4q15, was enFeLV present in both homologues of all four cats. A single enFeLV occurred in the X chromosome of the Burmese cat, while three to five enFeLV proviruses occurred in each Y chromosome. The X chromosome and nine autosomal enFeLV loci were telomeric, suggesting that ectopic recombination between nonhomologous subtelomeres may contribute to enFeLV distribution. Since endogenous FeLVs may affect the infectiousness or pathogenicity of exogenous FeLVs, genomic variation in enFeLVs represents a candidate for genetic influences on FeLV leukemogenesis in cats. PMID:15767400

  18. IGHV1-69-Encoded Antibodies Expressed in Chronic Lymphocytic Leukemia React with Malondialdehyde-Acetaldehyde Adduct, an Immunodominant Oxidation-Specific Epitope

    DEFF Research Database (Denmark)

    Que, Xuchu; Widhopf Ii, George F; Amir, Shahzada

    2013-01-01

    The immunoglobulins expressed by chronic lymphocytic leukemia (CLL) B cells are highly restricted, suggesting they are selected for binding either self or foreign antigen. Of the immunoglobulin heavy-chain variable (IGHV) genes expressed in CLL, IGHV1-69 is the most common, and often is expressed...... are products of enhanced lipid peroxidation and a major target of innate natural antibodies. Specifically, CLL69C bound immunodominant OSE adducts termed MAA (malondialdehyde-acetaldehyde-adducts), which are found on apoptotic cells, inflammatory tissues, and atherosclerotic lesions. It also reacted...

  19. Neutralizing antibodies induced by recombinant virus-like particles of enterovirus 71 genotype C4 inhibit infection at pre- and post-attachment steps.

    Directory of Open Access Journals (Sweden)

    Zhiqiang Ku

    Full Text Available BACKGROUND: Enterovirus 71 (EV71 is a major causative agent of hand, foot and mouth disease, which has been prevalent in Asia-Pacific regions, causing significant morbidity and mortality in young children. Antibodies elicited by experimental EV71 vaccines could neutralize infection in vitro and passively protect animal models from lethal challenge, indicating that neutralizing antibodies play an essential role in protection. However, how neutralizing antibodies inhibit infection in vitro remains unclear. METHODS/FINDINGS: In the present study, we explored the mechanisms of neutralization by antibodies against EV71 virus-like particles (VLPs. Recombinant VLPs of EV71 genotype C4 were produced in insect cells using baculovirus vectors. Immunization with the VLPs elicited a high-titer, EV71-specific antibody response in mice. Anti-VLP mouse sera potently neutralized EV71 infection in vitro. The neutralizing antibodies in the anti-VLP mouse sera were found to target mainly an extremely conserved epitope (FGEHKQEKDLEYGAC located at the GH loop of the VP1 protein. The neutralizing anti-VLP antisera were able to inhibit virus binding to target cells efficiently. In addition, post-attachment treatment of virus-bound cells with the anti-VLP antisera also neutralized virus infection, although the antibody concentration required was higher than that of the pre-attachment treatment. CONCLUSIONS: Collectively, our findings represent a valuable addition to the understanding of mechanisms of EV71 neutralization and have strong implications for EV71 vaccine development.

  20. Role of neutralizing antibodies and T-cells in pathogenesis of herpes simplex virus infection in congenitally athymic mice.

    Science.gov (United States)

    Kapoor, A K; Buckmaster, A; Nash, A A; Field, H J; Wildy, P

    1982-11-01

    Congenitally athymic nude mice were infected with 10(4) p.f.u. herpes simplex type 1 (strain SC16). Following the passive transfer of neutralizing monoclonal antibodies (AP7, AP8 and AP12) it was observed that AP7 alone reduced the virus infectivity in the nervous system; AP8 and AP12 failed to protect mice probably due to poor in vivo binding to the neutralization site on the virus. Latent ganglionic infection could be established in nude mice following adoptive transfer of optimum number (2 x 10(7) cells/mouse) of immune lymph node cells from day 7 herpes virus-infected hairy immunocompetent donor mice. Moreover, in some of the immune lymph node cell protected nudes, latency could be maintained even in complete absence of neutralizing antibodies. Results of ear-ablation experiments revealed that removal of primary source of infection after day 5 of infection reduced the amount of virus in the ganglia and spinal cord. Acute neurological infection was not detected following transfer of protective anti-gp-D neutralizing antibody (LP2) in combination with removal of infected pinna. These data suggest that continuous seeding of virus occurs in related ganglia via the axonal route from infected ear pinna. It appears that local T-cell-mediated immune mechanisms are involved in maintenance of latency.

  1. Characterization of anti-liver-kidney microsome antibody (anti-LKM1) from hepatitis C virus-positive and -negative sera.

    Science.gov (United States)

    Yamamoto, A M; Cresteil, D; Homberg, J C; Alvarez, F

    1993-06-01

    Hepatitis C virus-related antibodies were found in sera positive for antibodies to liver/kidney microsome antibody, usually considered a marker of autoimmune hepatitis. The aim of this study was to analyze the specificity of this autoantibody in sera from patients with and without hepatitis C virus infection. Fifteen anti-hepatitis C virus- and anti-liver kidney microsome-positive sera were compared with 11 sera from patients with autoimmune hepatitis, for reactivity against rat and human liver microsomal proteins, P450IID6 recombinant proteins, and various synthetic peptides spanning the 241-429 amino acids sequence of the P450IID6. Ten of 11 sera from patients with autoimmune hepatitis bound to recombinant proteins spanning the P450IID6 region between amino acids 72 and 458. These sera bound to the 254-271 peptide, and some also recognized the 321-351, 373-389 and 410-429 peptides. Four of 15 antihepatitis C virus recognized the fusion protein coded by the full-length P450IID6 complementary DNA; 3 of them also reacted with the P450IID6 region between amino acids 72-456. Only 1 sera recognized the 321-351 peptide. P450IID6 antigenic sites recognized by anti-hepatitis C virus-positive sera were different from those recognized by sera from patients with autoimmune hepatitis.

  2. The relationship between antibody status to bovine corona virus and bovine respiratory syncytial virus and disease incidence, reproduction and herd characteristics in dairy herds

    Directory of Open Access Journals (Sweden)

    Tråvén Madeleine

    2010-06-01

    Full Text Available Abstract Background Bovine respiratory syncytial virus (BRSV and bovine corona virus (BCV affects cattle worldwide. Our objective was to evaluate the effects of these infections on general health and reproduction parameters measurable on herd level and to explore the association between antibody status and some herd characteristics. Methods We collected a pooled milk sample from five primiparous cows from 79 Swedish dairy herds in September 2006. The samples were analysed for immunoglobulin G antibodies to BCV and BRSV with indirect enzyme-linked immunosorbent assays. Herd level data from 1 September 2005 to 30 August 2006 were accessed retrospectively. The location of the herds was mapped using a geographical information system. Results Ten herds were antibody negative to both viruses and were compared with 69 herds positive to BCV or BRSV or both. Positive herds had a higher (P = 0.001 bulk tank milk somatic cell count (BMSCC compared with negative herds. The medians for all other analyzed health and reproductive parameters were consistently in favour of the herds negative to both viruses although the differences were not statistically significant. A higher proportion (P = 0.01 of herds used professional technicians for artificial insemination, rather than farm personnel, amongst the 33 herds negative to BCV compared with the 46 positive herds. Conclusions Our result shows that herds that were antibody positive to BCV and/or BRSV had a higher BMSCC compared with herds negative to BCV and BRSV. There was also tendency that negative herds had a better general herd health compared with positive. A higher proportion amongst the BCV negative herds used external technicians for AI instead of farm personnel, indicating that it is possible to avoid infection although having regular visits. Negative herds were located in close proximity to positive herds, indicating that local spread and airborne transmission between herds might not be of great

  3. Generation of Recombinant Schmallenberg Virus Nucleocapsid Protein in Yeast and Development of Virus-Specific Monoclonal Antibodies

    Directory of Open Access Journals (Sweden)

    Justas Lazutka

    2014-01-01

    Full Text Available Schmallenberg virus (SBV, discovered in continental Europe in late 2011, causes mild clinical signs in adult ruminants, including diarrhoea and reduced milk yield. However, fetal infection can lead to severe malformation in newborn offspring. To develop improved reagents for SBV serology, a high-level yeast expression system was employed to produce recombinant SBV nucleocapsid (N protein. Recombinant SBV N protein was investigated as an antigen in SBV-specific IgG enzyme immunoassay and used for generation of monoclonal antibodies (MAbs. Yeast-expressed SBV N protein was reactive with anti-SBV IgG-positive cow serum specimens collected from different farms of Lithuania. After immunization of mice with recombinant SBV N protein, four MAbs were generated. The MAbs raised against recombinant SBV N protein reacted with native viral nucleocapsids in SBV-infected BHK cells by immunofluorescence assay. The reactivity of recombinant N protein with SBV-positive cow serum specimens and the ability of the MAbs to recognize virus-infected cells confirm the antigenic similarity between yeast-expressed SBV N protein and native viral nucleocapsids. Our study demonstrates that yeast expression system is suitable for high-level production of recombinant SBV N protein and provides the first evidence on the presence of SBV-specific antibodies in cow serum specimens collected in Lithuania.

  4. Epidemiology of acute lymphoblastic leukemia

    International Nuclear Information System (INIS)

    Pendergrass, T.W.

    1985-01-01

    Although the etiology of acute leukemia is largely unknown, some facets of the puzzle are becoming clarified. Recognition of important patterns in age-specific mortality rates has suggested that events early in life, perhaps even prenatally, may have an influence on developing leukemia in childhood. The racial differences evident in mortality, incidence, and immunologic subtype of ALL suggest either differences in exposures to certain factors or differences in responses to those factors by white children. Hereditary factors appear to play a role. Familial and hereditary conditions exist that have high incidences of acute leukemia. Chromosomal anomalies are common in these conditions. Viral infections may play a role by contributing to alteration in genetic material through incorporation of the viral genome. How that virus is dealt with after primary infection seems important. The presence of immunodeficiency may allow wider dissemination or enhanced replication of such viruses, thereby increasing the likelihood of cellular transformation to an abnormal cell. Proliferation of that malignant cell to a clone may depend on other cofactors. Perhaps prolonged exposure to substances like benzene or alkylating agents may enhance these interactions between virus and genetic material. Does this change DNA repair mechanisms. Are viral infections handled differently. Is viral genomic information more easily integrated into host cells. Ionizing radiation has multiple effects. Alteration in genetic material occurs both at the molecular and chromosomal levels. DNA may be altered, lost, or added in the cell's attempt to recover from the injury

  5. Mouse Hepatitis Virus Strain A59 and Blocking Antireceptor Monoclonal Antibody Bind to the N-Terminal Domain of Cellular Receptor

    Science.gov (United States)

    Dveksler, Gabriela S.; Pensiero, Michael N.; Dieffenbach, Carl W.; Cardellichio, Christine B.; Basile, Alexis A.; Elia, Patrick E.; Holmes, Kathryn V.

    1993-03-01

    Mouse hepatitis virus (MHV) strain A59 uses as cellular receptors members of the carcinoembryonic antigen family in the immunoglobulin superfamily. Recombinant receptor proteins with deletions of whole or partial immunoglobulin domains were used to identify the regions of receptor glycoprotein recognized by virus and by antireceptor monoclonal antibody CC1, which blocks infection of murine cells. Monoclonal antibody CC1 and MHV-A59 virions bound only to recombinant proteins containing the entire first domain of MHV receptor. To determine which of the proteins could serve as functional virus receptors, receptor-negative hamster cells were transfected with recombinant deletion clones and then challenged with MHV-A59 virions. Receptor activity required the entire N-terminal domain with either the second or the fourth domain and the transmembrane and cytoplasmic domains. Recombinant proteins lacking the first domain or its C-terminal portion did not serve as viral receptors. Thus, like other virus receptors in the immunoglobulin superfamily, including CD4, poliovirus receptor, and intercellular adhesion molecule 1, the N-terminal domain of MHV receptor is recognized by the virus and the blocking monoclonal antibody.

  6. Endophilins interact with Moloney murine leukemia virus Gag and modulate virion production

    Directory of Open Access Journals (Sweden)

    De Camilli Pietro

    2003-12-01

    Full Text Available Abstract Background The retroviral Gag protein is the central player in the process of virion assembly at the plasma membrane, and is sufficient to induce the formation and release of virus-like particles. Recent evidence suggests that Gag may co-opt the host cell's endocytic machinery to facilitate retroviral assembly and release. Results A search for novel partners interacting with the Gag protein of the Moloney murine leukemia virus (Mo-MuLV via the yeast two-hybrid protein-protein interaction assay resulted in the identification of endophilin 2, a component of the machinery involved in clathrin-mediated endocytosis. We demonstrate that endophilin interacts with the matrix or MA domain of the Gag protein of Mo-MuLV, but not of human immunodeficiency virus, HIV. Both exogenously expressed and endogenous endophilin are incorporated into Mo-MuLV viral particles. Titration experiments suggest that the binding sites for inclusion of endophilin into viral particles are limited and saturable. Knock-down of endophilin with small interfering RNA (siRNA had no effect on virion production, but overexpression of endophilin and, to a lesser extent, of several fragments of the protein, result in inhibition of Mo-MuLV virion production, but not of HIV virion production. Conclusions This study shows that endophilins interact with Mo-MuLV Gag and affect virion production. The findings imply that endophilin is another component of the large complex that is hijacked by retroviruses to promote virion production.

  7. Human broadly neutralizing antibodies to the envelope glycoprotein complex of hepatitis C virus

    DEFF Research Database (Denmark)

    Giang, Erick; Dorner, Marcus; Prentoe, Jannick C

    2012-01-01

    , and an effective vaccine should target conserved T- and B-cell epitopes of the virus. Conserved B-cell epitopes overlapping the CD81 receptor-binding site (CD81bs) on the E2 viral envelope glycoprotein have been reported previously and provide promising vaccine targets. In this study, we isolated 73 human m......Abs recognizing five distinct antigenic regions on the virus envelope glycoprotein complex E1E2 from an HCV-immune phage-display antibody library by using an exhaustive-panning strategy. Many of these mAbs were broadly neutralizing. In particular, the mAb AR4A, recognizing a discontinuous epitope outside the CD81......bs on the E1E2 complex, has an exceptionally broad neutralizing activity toward diverse HCV genotypes and protects against heterologous HCV challenge in a small animal model. The mAb panel will be useful for the design and development of vaccine candidates to elicit broadly neutralizing antibodies...

  8. Expression of HER2/Neu in B-Cell Acute Lymphoblastic Leukemia.

    Science.gov (United States)

    Rodriguez-Rodriguez, Sergio; Pomerantz, Alan; Demichelis-Gomez, Roberta; Barrera-Lumbreras, Georgina; Barrales-Benitez, Olga; Aguayo-Gonzalez, Alvaro

    2016-01-01

    The expression of HER2/neu in B-cell acute lymphoblastic leukemia has been reported in previous studies. The objective of this research was to study the expression of HER2/neu on the blasts of patients with acute leukemia from the Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran. From June 2015 to February 2016, a HER2/neu monoclonal antibody was added to the panel of antibodies that we routinely use in patients with acute leukemia. An expression of ≥ 30% was considered positive. We studied 33 patients: 19 had de novo leukemia (57.6%), three (9.1%) were in relapse, and in 11 (33.3%) their status could not be specified. Seventeen patients (51.5%) were classified as B-cell acute lymphoblastic leukemia with a median expression of HER2/neu of 0.3% (range 0-90.2). Three patients with B-cell acute lymphoblastic leukemia were positive for HER2/neu: 89.4%, 90.9%, and 62.4%. The first and third patient had de novo B-cell acute lymphoblastic leukemia. The second patient was in second relapse after allogeneic stem cell transplant. All three patients were categorized as high-risk at the time of diagnosis. In the studied Mexican population, we found a positive expression of HER2/neu in 17% of the B-cell acute lymphoblastic leukemia patients, similar to previous studies in which the expression was found in 15-50%.

  9. Enhancers Are Major Targets for Murine Leukemia Virus Vector Integration

    Science.gov (United States)

    De Ravin, Suk See; Su, Ling; Theobald, Narda; Choi, Uimook; Macpherson, Janet L.; Poidinger, Michael; Symonds, Geoff; Pond, Susan M.; Ferris, Andrea L.; Hughes, Stephen H.

    2014-01-01

    ABSTRACT Retroviral vectors have been used in successful gene therapies. However, in some patients, insertional mutagenesis led to leukemia or myelodysplasia. Both the strong promoter/enhancer elements in the long terminal repeats (LTRs) of murine leukemia virus (MLV)-based vectors and the vector-specific integration site preferences played an important role in these adverse clinical events. MLV integration is known to prefer regions in or near transcription start sites (TSS). Recently, BET family proteins were shown to be the major cellular proteins responsible for targeting MLV integration. Although MLV integration sites are significantly enriched at TSS, only a small fraction of the MLV integration sites (integration map of more than one million integration sites from CD34+ hematopoietic stem cells transduced with a clinically relevant MLV-based vector. The integration sites form ∼60,000 tight clusters. These clusters comprise ∼1.9% of the genome. The vast majority (87%) of the integration sites are located within histone H3K4me1 islands, a hallmark of enhancers. The majority of these clusters also have H3K27ac histone modifications, which mark active enhancers. The enhancers of some oncogenes, including LMO2, are highly preferred targets for integration without in vivo selection. IMPORTANCE We show that active enhancer regions are the major targets for MLV integration; this means that MLV preferentially integrates in regions that are favorable for viral gene expression in a variety of cell types. The results provide insights for MLV integration target site selection and also explain the high risk of insertional mutagenesis that is associated with gene therapy trials using MLV vectors. PMID:24501411

  10. Application of solid-phase radioimmunoassay in determining antibodies to Aujeszky's disease virus in blood serum of vaccinated pigs

    Energy Technology Data Exchange (ETDEWEB)

    Rodak, L.; Smid, B.; Valicek, L. (Vyzkumny Ustav Veterinarniho Lekarstvi, Brno-Medlanky (Czechoslovakia))

    1983-11-01

    In the blood sera of pigs vaccinated with inactivated vaccines manufactured by three different manufacturers the RIA method was used to determine the specific antibodies to the virus of Aujeszky's disease. In certain groups of vaccinated pigs the results of the RIA examination are unfavourably affected by the bond of antibodies to the cellular antigenous determinants. This proves that following vaccination antibodies are formed not only against the viral antigen but also against the antigens of cells on which the vaccination virus is propagated. These shortcomings are eliminated by the use of suitable cellular cultures for the preparation of viral and control antigens. Antigens are applicable for RIA and for ELISA examinations of blood sera of infected and vaccinated pigs. The advantages are described of the RIA and ELISA methods as compared with the virus neutralization test.

  11. Functional Interplay Between Murine Leukemia Virus Glycogag, Serinc5, and Surface Glycoprotein Governs Virus Entry, with Opposite Effects on Gammaretroviral and Ebolavirus Glycoproteins

    Directory of Open Access Journals (Sweden)

    Yadvinder S. Ahi

    2016-11-01

    Full Text Available Gammaretroviruses, such as murine leukemia viruses (MLVs, encode, in addition to the canonical Gag, Pol, and Env proteins that will form progeny virus particles, a protein called “glycogag” (glycosylated Gag. MLV glycogag contains the entire Gag sequence plus an 88-residue N-terminal extension. It has recently been reported that glycogag, like the Nef protein of HIV-1, counteracts the antiviral effects of the cellular protein Serinc5. We have found, in agreement with prior work, that glycogag strongly enhances the infectivity of MLVs with some Env proteins but not those with others. In contrast, however, glycogag was detrimental to MLVs carrying Ebolavirus glycoprotein. Glycogag could be replaced, with respect to viral infectivity, by the unrelated S2 protein of equine infectious anemia virus. We devised an assay for viral entry in which virus particles deliver the Cre recombinase into cells, leading to the expression of a reporter. Data from this assay showed that both the positive and the negative effects of glycogag and S2 upon MLV infectivity are exerted at the level of virus entry. Moreover, transfection of the virus-producing cells with a Serinc5 expression plasmid reduced the infectivity and entry capability of MLV carrying xenotropic MLV Env, particularly in the absence of glycogag. Conversely, Serinc5 expression abrogated the negative effects of glycogag upon the infectivity and entry capability of MLV carrying Ebolavirus glycoprotein. As Serinc5 may influence cellular phospholipid metabolism, it seems possible that all of these effects on virus entry derive from changes in the lipid composition of viral membranes.

  12. Detection of antibody responses by using haemagglutination inhibiton test and the protection titer of avian influenza virus H5N1 subtype

    Directory of Open Access Journals (Sweden)

    Risa Indriani

    2004-10-01

    Full Text Available Study on the detection of antibody responses using haemagglutination inhibition (HI test and the protection titer to Avian influenza (AI virus H5N1 subtype local isolate has been conducted at the Research Institute for Veterinary Science (RIVS. A total number of 50 village chicken (10 chicken served as un-injected controls and 30 quail were injected intramuscularly with inactivated virus of AI H5N1 subtype local isolate. Serum samples were collected 3 weeks after injection and were tested using haemagglutination inhibition tests. The correlation between antibody titer and its protection to AI virus H5N1 local isolate were measured by challenging the birds with AI virus H5N1 local isolate The HI test was then used to determine field serum samples. A total number of 48 village chicken from three (3 Districts (Bekasi, Tangerang and Bogor and 96 quails from two (2 farms in District of Sukabumi which were all vaccinated with commercial AI adjuvant vaccine were sampled. The study revealed that village chicken and quails showed antibody responses after 3 weeks vaccination and that titer of ≥ 3 log 2 was able to protect chicken and quails when they were challenged with local isolate virus. Based on this result, village chicken field samples from Districts of Tangerang, Bekasi and Bogor showed antibody titer which will protect 50, 100 and 85% of the flocks respectively. While quail field samples from Farm I and Farm II in District of Sukabumi showed antibody titer which will protect 60-100% and 0-80% of the flocks respectively. It is concluded that the study has successfully measured antibody titer to AI virus H5N1 subtype which protect village chicken and quails from local isolate virus challenge so that the results will be used to analyze field serum samples after vaccination program to eradicate AI from Indonesia.

  13. The Antiviral Mechanism of an Influenza A Virus Nucleoprotein-Specific Single-Domain Antibody Fragment

    Energy Technology Data Exchange (ETDEWEB)

    Hanke, Leo; Knockenhauer, Kevin E.; Brewer, R. Camille; van Diest, Eline; Schmidt, Florian I.; Schwartz, Thomas U.; Ploegh, Hidde L. (Whitehead); (MIT)

    2016-12-13

    Alpaca-derived single-domain antibody fragments (VHHs) that target the influenza A virus nucleoprotein (NP) can protect cells from infection when expressed in the cytosol. We found that one such VHH, αNP-VHH1, exhibits antiviral activity similar to that of Mx proteins by blocking nuclear import of incoming viral ribonucleoproteins (vRNPs) and viral transcription and replication in the nucleus. We determined a 3.2-Å crystal structure of αNP-VHH1 in complex with influenza A virus NP. The VHH binds to a nonconserved region on the body domain of NP, which has been associated with binding to host factors and serves as a determinant of host range. Several of the NP/VHH interface residues determine sensitivity of NP to antiviral Mx GTPases. The structure of the NP/αNP-VHH1 complex affords a plausible explanation for the inhibitory properties of the VHH and suggests a rationale for the antiviral properties of Mx proteins. Such knowledge can be leveraged for much-needed novel antiviral strategies.

    IMPORTANCEInfluenza virus strains can rapidly escape from protection afforded by seasonal vaccines or acquire resistance to available drugs. Additional ways to interfere with the virus life cycle are therefore urgently needed. The influenza virus nucleoprotein is one promising target for antiviral interventions. We have previously isolated alpaca-derived single-domain antibody fragments (VHHs) that protect cells from influenza virus infection if expressed intracellularly. We show here that one such VHH exhibits antiviral activities similar to those of proteins of the cellular antiviral defense (Mx proteins). We determined the three-dimensional structure of this VHH in complex with the influenza virus nucleoprotein and identified the interaction site, which overlaps regions that determine sensitivity of the virus to Mx proteins. Our data define a new vulnerability of influenza virus, help us to better understand the cellular antiviral mechanisms, and

  14. [Report of a case of megakaryoblastic leukemia].

    Science.gov (United States)

    Monteiro, J A; Timóteo, T; Elisário, L

    1990-01-01

    We diagnosed a 20 year old young girl, with clinical and laboratorial evidence of pancytopenia, an acute megakaryoblastic leukemia. The difficulty in arriving at this conclusion was only surpassed with the help of monoclonal antibodies. With the presentation of this case we approach the problematics in obtaining the diagnostic of the megakaryoblastic leukemia. This is fundamental, owing to the possibilities of morphological presentation under undifferentiated blasts or of the type M1 or L2 (FAB).

  15. Production of Polyclonal Antibody against Grapevine fanleaf virus Movement Protein Expressed in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Davoud Koolivand

    2016-10-01

    Full Text Available The genomic region of Grapevine fanleaf virus (GFLV encoding the movement protein (MP was cloned into pET21a and transformed into Escherichia coli strain BL21 (DE3 to express the protein. Induction was made with a wide range of isopropyl-β-D-thiogalactopyranoside (IPTG concentrations (1, 1.5, and 2 mM each for duration of 4, 6, or 16 h. However, the highest expression level was achieved with 1 mM IPTG for 4 h. Identity of the expressed protein was confirmed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE followed by Western blotting. The expressed 41 kDa protein was purified under denaturing condition by affinity chromatography, reconfirmed by Western blotting and plate-trapped antigen enzyme-linked immunosorbent assay (PTA-ELISA before being used as a recombinant antigen to raise polyclonal antibodies in rabbits. Purified anti-GFLV MP immunoglobulines (IgGs and conjugated IgGs detected the expressed MP and GFLV virions in infected grapevines when used in PTA-ELISA, double antibody sandwich-ELISA, and Western blotting. This is the first report on the production of anti-GFLV MP polyclonal antibodies and application for the virus detection.

  16. Development of a novel monoclonal antibody with reactivity to a wide range of Venezuelan equine encephalitis virus strains

    Directory of Open Access Journals (Sweden)

    Phelps Amanda L

    2009-11-01

    Full Text Available Abstract Background There is currently a requirement for antiviral therapies capable of protecting against infection with Venezuelan equine encephalitis virus (VEEV, as a licensed vaccine is not available for general human use. Monoclonal antibodies are increasingly being developed as therapeutics and are potential treatments for VEEV as they have been shown to be protective in the mouse model of disease. However, to be truly effective, the antibody should recognise multiple strains of VEEV and broadly reactive monoclonal antibodies are rarely and only coincidentally isolated using classical hybridoma technology. Results In this work, methods were developed to reliably derive broadly reactive murine antibodies. A phage library was created that expressed single chain variable fragments (scFv isolated from mice immunised with multiple strains of VEEV. A broadly reactive scFv was identified and incorporated into a murine IgG2a framework. This novel antibody retained the broad reactivity exhibited by the scFv but did not possess virus neutralising activity. However, the antibody was still able to protect mice against VEEV disease induced by strain TrD when administered 24 h prior to challenge. Conclusion A monoclonal antibody possessing reactivity to a wide range of VEEV strains may be of benefit as a generic antiviral therapy. However, humanisation of the murine antibody will be required before it can be tested in humans. Crown Copyright © 2009

  17. Broadly-reactive human monoclonal antibodies elicited following pandemic H1N1 influenza virus exposure protect mice from highly pathogenic H5N1 challenge.

    Science.gov (United States)

    Nachbagauer, Raffael; Shore, David; Yang, Hua; Johnson, Scott K; Gabbard, Jon D; Tompkins, S Mark; Wrammert, Jens; Wilson, Patrick C; Stevens, James; Ahmed, Rafi; Krammer, Florian; Ellebedy, Ali H

    2018-06-13

    Broadly cross-reactive antibodies that recognize conserved epitopes within the influenza virus hemagglutinin (HA) stalk domain are of particular interest for their potential use as therapeutic and prophylactic agents against multiple influenza virus subtypes including zoonotic virus strains. Here, we characterized four human HA stalk-reactive monoclonal antibodies (mAbs) for their binding breadth and affinity, in vitro neutralization capacity, and in vivo protective potential against an highly pathogenic avian influenza virus. The monoclonal antibodies were isolated from individuals shortly following infection with (70-1F02 and 1009-3B05) or vaccination against (05-2G02 and 09-3A01) A(H1N1)pdm09. Three of the mAbs bound HAs from multiple strains of group 1 viruses, and one mAb, 05-2G02, bound to both group 1 and group 2 influenza A HAs. All four antibodies prophylactically protected mice against a lethal challenge with the highly pathogenic A/Vietnam/1203/04 (H5N1) strain. Two mAbs, 70-1F02 and 09-3A01, were further tested for their therapeutic efficacy against the same strain and showed good efficacy in this setting as well. One mAb, 70-1F02, was co-crystallized with H5 HA and showed similar heavy chain only interactions as a the previously described anti-stalk antibody CR6261. Finally, we showed that antibodies that compete with these mAbs are prevalent in serum from an individual recently infected with A(H1N1)pdm09 virus. The antibodies described here can be developed into broad-spectrum antiviral therapeutics that could be used to combat infections with zoonotic or emerging pandemic influenza viruses. IMPORTANCE The rise in zoonotic infections of humans with emerging influenza viruses is a worldwide public health concern. The majority of recent zoonotic human influenza cases were caused by H7N9 and H5Nx viruses and were associated with high morbidity and mortality. In addition, seasonal influenza viruses are estimated to cause up to 650,000 deaths annually

  18. Domestic cat microsphere immunoassays: detection of antibodies during feline immunodeficiency virus infection.

    Science.gov (United States)

    Wood, Britta A; Carver, Scott; Troyer, Ryan M; Elder, John H; VandeWoude, Sue

    2013-10-31

    Microsphere immunoassays (MIAs) allow rapid and accurate evaluation of multiple analytes simultaneously within a biological sample. Here we describe the development and validation of domestic cat-specific MIAs for a) the quantification of total IgG and IgA levels in plasma, and b) the detection of IgG and IgA antibodies to feline immunodeficiency virus (FIV) capsid (CA) and surface (SU) proteins, and feline CD134 in plasma. These assays were used to examine the temporal antibody response of domestic cats infected with apathogenic and pathogenic FIVs, and domestic cats infected with parental and chimeric FIVs of varying pathogenicity. The results from these studies demonstrated that a) total IgG antibodies increase over time after infection; b) α-CA and α-SU IgG antibodies are detectable between 9 and 28 days post-infection and increase over time, and these antibodies combined represent a fraction (1.8 to 21.8%) of the total IgG increase due to infection; c) measurable α-CD134 IgG antibody levels vary among individuals and over time, and are not strongly correlated with viral load; d) circulating IgA antibodies, in general, do not increase during the early stage of infection; and e) total IgG, and α-CA and α-SU IgG antibody kinetics and levels vary with FIV viral strain/pathogenicity. The MIAs described here could be used to screen domestic cats for FIV infection, and to evaluate the FIV-specific or total antibody response elicited by various FIV strains/other diseases. © 2013.

  19. Proteasome Inhibition Suppresses Dengue Virus Egress in Antibody Dependent Infection.

    Directory of Open Access Journals (Sweden)

    Milly M Choy

    2015-11-01

    Full Text Available The mosquito-borne dengue virus (DENV is a cause of significant global health burden, with an estimated 390 million infections occurring annually. However, no licensed vaccine or specific antiviral treatment for dengue is available. DENV interacts with host cell factors to complete its life cycle although this virus-host interplay remains to be fully elucidated. Many studies have identified the ubiquitin proteasome pathway (UPP to be important for successful DENV production, but how the UPP contributes to DENV life cycle as host factors remains ill defined. We show here that proteasome inhibition decouples infectious virus production from viral RNA replication in antibody-dependent infection of THP-1 cells. Molecular and imaging analyses in β-lactone treated THP-1 cells suggest that proteasome function does not prevent virus assembly but rather DENV egress. Intriguingly, the licensed proteasome inhibitor, bortezomib, is able to inhibit DENV titers at low nanomolar drug concentrations for different strains of all four serotypes of DENV in primary monocytes. Furthermore, bortezomib treatment of DENV-infected mice inhibited the spread of DENV in the spleen as well as the overall pathological changes. Our findings suggest that preventing DENV egress through proteasome inhibition could be a suitable therapeutic strategy against dengue.

  20. Detection of Schmallenberg virus antibody in equine population of Northern and Northeast of Iran.

    Science.gov (United States)

    Rasekh, M; Sarani, A; Hashemi, S H

    2018-01-01

    Schmallenberg virus (SBV) is a newly emerging virus in Simbu group that 1 st time is reported in 2011 in Germany and now spread to Europe. The clinical signs of infection to this virus are fever, loss of appetite, reduced milk yield and in some cases, diarrhea and in pregnant animals congenital malformations in calves, lambs, and kid goats. In this study for a serologic survey of SBV, blood samples from 200 horse in different rural areas of the northern and northeast of Iran with the high equine population collected and were analyzed using an indirect ELISA test. Based on our results 5% (n=10) of total 200 samples were positive for SBV antibody and 2% (n=4) was doubtful and 93% (n=186) was negative. There were no significant differences between age and sex and breed properties (p>0.05). This study demonstrated the presence of antibodies against the SBV on horse populations in Iran. The high population and activity of Culicoides biting midges and their proper living conditions, especially the areas of temperate and humid environmental conditions, are the possible causes of arboviruses related diseases seen in this country.

  1. Vaccine-induced cross-genotype reactive neutralizing antibodies against hepatitis C virus

    DEFF Research Database (Denmark)

    Meunier, Jean-Christophe; Gottwein, Judith M; Houghton, Michael

    2011-01-01

    We detected cross-reactive neutralizing antibodies (NtAb) against hepatitis C virus (HCV) in chimpanzees vaccinated with HCV-1 (genotype 1a) recombinant E1/E2 envelope glycoproteins. Five vaccinated chimpanzees, protected following HCV-1 challenge, were initially studied using the heterologous H77......a, with limited reactivity against 2a and 3a. Our study provides encouragement for the development of a recombinant envelope-based vaccine against hepatitis C....

  2. Specific detection of peste des petits ruminants virus antibodies in sheep and goat sera by the luciferase

    International Nuclear Information System (INIS)

    Berguido, F.J.; Bodjo, S.C.; Loitsch, A.; Diallo, A.

    2016-01-01

    Full text: Peste des petits ruminants (PPR) is a contagious and often fatal transboundary animal disease affecting mostly sheep, goats and wild small ruminants. This disease is endemic in most of Africa, the Middle, Near East, and large parts of Asia. The casual agent is peste des petits ruminants virus (PPRV), which belongs to the genus Morbilivirus in the family Paramyxoviridae. This genus also includes measles virus (MV), canine distemper virus (CDV) and rinderpest virus (RPV). All are closely related viruses with serological cross reactivity. In this study, we have developed a Luciferase Immunoprecipitation System (LIPS) for the rapid detection of antibodies against PPRV in serum samples and for specific differentiation from antibodies against RPV. PPR and rinderpest (RP) serum samples were assayed by PPR-LIPS and two commercially available PPR cELISA tests. The PPR-LIPS showed high sensitivity and specificity for the samples tested and showed no cross reactivity with RPV unlike the commercial PPR cELISA tests which did not cross react with RPV. Based on the results shown in this study, PPR-LIPS is presented as a good candidate for the specific serosurveillance of PPR. (author)

  3. The HIV-1 V3 domain on field isolates: participation in generation of escape virus in vivo and accessibility to neutralizing antibodies

    DEFF Research Database (Denmark)

    Arendrup, M; Akerblom, L; Heegaard, P M

    1995-01-01

    The V3 domain is highly variable and induces HIV neutralizing antibodies (NA). Here we addressed the issues of 1) the participation of mutations in V3 in generation of neutralization resistant escape virus in vivo and 2) the applicability of synthetic V3 peptides corresponding to field isolates...... to induce neutralizing immune sera. Seven peptides corresponding to the V3 region of primary and escape virus from 3 HIV-1 infected patients were synthesized and used for antibody (Abs) studies and immunizations. The anti-V3 Abs titre in patient serum was generally low against peptides corresponding...... to autologous virus isolated later than the serum sample in contrast to the titre against peptides corresponding to virus isolated earlier than the serum sample. Furthermore, neutralizing anti-V3 monoclonal antibodies (MAbs) raised against V3 peptides from laboratory strains of HIV-1 showed distinct binding...

  4. Initiating a watch list for Ebola virus antibody escape mutations

    OpenAIRE

    Craig R. Miller; Erin L. Johnson; Aran Z. Burke; Kyle P. Martin; Tanya A. Miura; Holly A. Wichman; Celeste J. Brown; F. Marty Ytreberg

    2016-01-01

    The 2014 Ebola virus (EBOV) outbreak in West Africa is the largest in recorded history and resulted in over 11,000 deaths. It is essential that strategies for treatment and containment be developed to avoid future epidemics of this magnitude. With the development of vaccines and antibody-based therapies using the envelope glycoprotein (GP) of the 1976 Mayinga strain, one important strategy is to anticipate how the evolution of EBOV might compromise these efforts. In this study we have initiat...

  5. GLUT-1-independent infection of the glioblastoma/astroglioma U87 cells by the human T cell leukemia virus type 1

    International Nuclear Information System (INIS)

    Jin Qingwen; Agrawal, Lokesh; VanHorn-Ali, Zainab; Alkhatib, Ghalib

    2006-01-01

    The human glucose transporter protein 1 (GLUT-1) functions as a receptor for human T cell leukemia virus (HTLV). GLUT-1 is a twelve-transmembrane cell surface receptor with six extracellular (ECL) and seven intracellular domains. To analyze HTLV-1 cytotropism, we utilized polyclonal antibodies to a synthetic peptide corresponding to the large extracellular domain of GLUT-1. The antibodies caused significant blocking of envelope (Env)-mediated fusion and pseudotyped virus infection of HeLa cells but had no significant effect on infection of U87 cells. This differential effect correlated with the detection of high-level surface expression of GLUT-1 on HeLa cells and very weak staining of U87 cells. To investigate this in terms of viral cytotropism, we cloned GLUT-1 cDNA from U87 cells and isolated two different versions of cDNA clones: the wild-type sequence (encoding 492 residues) and a mutant cDNA with a 5-base pair deletion (GLUT-1Δ5) between nucleotides 1329 and 1333. The deletion, also detected in genomic DNA, resulted in a frame-shift and premature termination producing a truncated protein of 463 residues. Transfection of the wild-type GLUT-1 but not GLUT-1Δ5 cDNA into CHO cells resulted in efficient surface expression of the human GLUT-1. Co-expression of GLUT-1 with GLUT-1Δ5 produces a trans-inhibition by GLUT-1Δ5 of GLUT-1-mediated HTLV-1 envelope (Env)-mediated fusion. Co-immunoprecipitation experiments demonstrated physical interaction of the wild-type and mutant proteins. Northern blot and RT-PCR analyses demonstrated lower GLUT-1 RNA expression in U87 cells. We propose two mechanisms to account for the impaired cell surface expression of GLUT-1 on U87 cells: low GLUT-1 RNA expression and the formation of GLUT-1/GLUT-1Δ5 heterodimers that are retained intracellularly. Significant RNAi-mediated reduction of endogenous GLUT-1 expression impaired HTLV-1 Env-mediated fusion with HeLa cells but not with U87 cells. We propose a GLUT-1-independent mechanism

  6. Structure of general-population antibody titer distributions to influenza A virus.

    Science.gov (United States)

    Nhat, Nguyen Thi Duy; Todd, Stacy; de Bruin, Erwin; Thao, Tran Thi Nhu; Vy, Nguyen Ha Thao; Quan, Tran Minh; Vinh, Dao Nguyen; van Beek, Janko; Anh, Pham Hong; Lam, Ha Minh; Hung, Nguyen Thanh; Thanh, Nguyen Thi Le; Huy, Huynh Le Anh; Ha, Vo Thi Hong; Baker, Stephen; Thwaites, Guy E; Lien, Nguyen Thi Nam; Hong, Tran Thi Kim; Farrar, Jeremy; Simmons, Cameron P; Chau, Nguyen Van Vinh; Koopmans, Marion; Boni, Maciej F

    2017-07-20

    Seroepidemiological studies aim to understand population-level exposure and immunity to infectious diseases. Their results are normally presented as binary outcomes describing the presence or absence of pathogen-specific antibody, despite the fact that many assays measure continuous quantities. A population's natural distribution of antibody titers to an endemic infectious disease may include information on multiple serological states - naiveté, recent infection, non-recent infection, childhood infection - depending on the disease in question and the acquisition and waning patterns of immunity. In this study, we investigate 20,152 general-population serum samples from southern Vietnam collected between 2009 and 2013 from which we report antibody titers to the influenza virus HA1 protein using a continuous titer measurement from a protein microarray assay. We describe the distributions of antibody titers to subtypes 2009 H1N1 and H3N2. Using a model selection approach to fit mixture distributions, we show that 2009 H1N1 antibody titers fall into four titer subgroups and that H3N2 titers fall into three subgroups. For H1N1, our interpretation is that the two highest-titer subgroups correspond to recent and historical infection, which is consistent with 2009 pandemic attack rates. Similar interpretations are available for H3N2, but right-censoring of titers makes these interpretations difficult to validate.

  7. SEROPREVALENCE OF ANTIBODIES TO HEPATITIS A VIRUS IN BLOODDONORS AND PATIENTS IN UNIVERSITY CLINICAL CENTER MARIBOR

    Directory of Open Access Journals (Sweden)

    Božislava Majcen Vivod

    2008-04-01

    Seroprevalence of anti-HAV antibodies declined in last decades in European countries. Inour study 20 % blood donors had antibodies anti-HAV in the group younger than 35 yearsand among patient only 15 % of patients had antibodies in the same group.The use of a vaccine against hepatitis A virus has to be considered for the prevention ofsymptomatic hepatitis, especially in adults at risk for infection, such as those who travel toareas with poor sanitation. Furthermore, they should take into consideration the fact thatthe severity of the disease increases with age

  8. [Establishment of chemiluminescent enzyme immunoassay for detecting antibodies against foot-and-mouth disease virus serotype O in swine].

    Science.gov (United States)

    Cui, Chen; Huang, Ligang; Li, Jing; Zou, Xingqi; Zhu, Yuanyuan; Xie, Lei; Zhao, Qizu; Yang, Limin; Liu, Wenjun

    2016-11-25

    Recombinant structural protein VP1 of foot-and-mouth disease virus serotype O was expressed in Escherichia coli and then purified using Nickel affinity chromatography. A chemiluminescent enzyme immunoassay (CLEIA) method was established using the purified recombinant protein as coating antigen to detect antibody of foot-and-mouth disease virus serotype O in swine. The specificity of VP1-CLEIA method is 100%. The coefficients of variation in the plate and between plates are 1.10%-6.70% and 0.66%-4.80%, respectively. Comparing with the commercial indirect ELISA kit or liquid phase block ELISA kit, the calculated coincidence rate is 93.50% or 94.00%. The high specificity and stability suggested this detection method can be used to monitor the antibody level of foot-and-mouth disease virus serotype O in swine.

  9. H9N2 avian influenza virus antibody titers in human population in fars province, Iran

    Directory of Open Access Journals (Sweden)

    MM Hadipour

    2010-09-01

    Full Text Available Among the avian influenza A virus subtypes, H5N1 and H9N2 viruses have the potential to cause an influenza pandemic because they are widely prevalent in avian species in Asia and have demonstrated the ability to infect humans. This study was carried out to determined the seroprevalence of H9N2 avian influenza virus in different human populations in Fars province, which is situated in the south of Iran. Antibodies against H9N2 avian influenza virus were measured using hemagglutination-inhibition (HI test in sera from 300 individuals in five different population in Fars province, including poultry-farm workers, slaughter-house workers, veterinarians, patients with clinical signs of respiratory disease, and clinically normal individuals, who were not or rarely in contact with poultry. Mean antibody titers of 7.3, 6.8, 6.1, 4.5, and 2.9 and seroprevalences of 87%, 76.2%, 72.5%, 35.6%, and 23% were determined in those groups, respectively. Higher prevalences were detected in poultry-farm workers, slaughter-house workers, and veterinarians, possibly due to their close and frequent contact with poultry.

  10. Absence of evidence of Xenotropic Murine Leukemia Virus-related virus infection in persons with Chronic Fatigue Syndrome and healthy controls in the United States

    Directory of Open Access Journals (Sweden)

    Switzer William M

    2010-07-01

    Full Text Available Abstract Background XMRV, a xenotropic murine leukemia virus (MuLV-related virus, was recently identified by PCR testing in 67% of persons with chronic fatigue syndrome (CFS and in 3.7% of healthy persons from the United States. To investigate the association of XMRV with CFS we tested blood specimens from 51 persons with CFS and 56 healthy persons from the US for evidence of XMRV infection by using serologic and molecular assays. Blinded PCR and serologic testing were performed at the US Centers for Disease Control and Prevention (CDC and at two additional laboratories. Results Archived blood specimens were tested from persons with CFS defined by the 1994 international research case definition and matched healthy controls from Wichita, Kansas and metropolitan, urban, and rural Georgia populations. Serologic testing at CDC utilized a Western blot (WB assay that showed excellent sensitivity to MuLV and XMRV polyclonal or monoclonal antibodies, and no reactivity on sera from 121 US blood donors or 26 HTLV-and HIV-infected sera. Plasma from 51 CFS cases and plasma from 53 controls were all WB negative. Additional blinded screening of the 51 cases and 53 controls at the Robert Koch Institute using an ELISA employing recombinant Gag and Env XMRV proteins identified weak seroreactivity in one CFS case and a healthy control, which was not confirmed by immunofluorescence. PCR testing at CDC employed a gag and a pol nested PCR assay with a detection threshold of 10 copies in 1 ug of human DNA. DNA specimens from 50 CFS patients and 56 controls and 41 US blood donors were all PCR-negative. Blinded testing by a second nested gag PCR assay at the Blood Systems Research Institute was also negative for DNA specimens from the 50 CFS cases and 56 controls. Conclusions We did not find any evidence of infection with XMRV in our U.S. study population of CFS patients or healthy controls by using multiple molecular and serologic assays. These data do not support an

  11. Novel antibody binding determinants on the capsid surface of serotype O foot-and-mouth disease virus

    Science.gov (United States)

    Asfor, Amin S.; Upadhyaya, Sasmita; Knowles, Nick J.; King, Donald P.; Paton, David J.

    2014-01-01

    Five neutralizing antigenic sites have been described for serotype O foot-and-mouth disease viruses (FMDV) based on monoclonal antibody (mAb) escape mutant studies. However, a mutant virus selected to escape neutralization of mAb binding at all five sites was previously shown to confer complete cross-protection with the parental virus in guinea pig challenge studies, suggesting that amino acid residues outside the mAb binding sites contribute to antibody-mediated in vivo neutralization of FMDV. Comparison of the ability of bovine antisera to neutralize a panel of serotype O FMDV identified three novel putative sites at VP2-74, VP2-191 and VP3-85, where amino acid substitutions correlated with changes in sero-reactivity. The impact of these positions was tested using site-directed mutagenesis to effect substitutions at critical amino acid residues within an infectious copy of FMDV O1 Kaufbeuren (O1K). Recovered viruses containing additional mutations at VP2-74 and VP2-191 exhibited greater resistance to neutralization with both O1K guinea pig and O BFS bovine antisera than a virus that was engineered to include only mutations at the five known antigenic sites. The changes at VP2-74 and VP3-85 are adjacent to critical amino acids that define antigenic sites 2 and 4, respectively. However VP2-191 (17 Å away from VP2-72), located at the threefold axis and more distant from previously identified antigenic sites, exhibited the most profound effect. These findings extend our knowledge of the surface features of the FMDV capsid known to elicit neutralizing antibodies, and will improve our strategies for vaccine strain selection and rational vaccine design. PMID:24584474

  12. Quantification and molecular characterization of the feline leukemia virus A receptor.

    Science.gov (United States)

    Katrin Helfer-Hungerbuehler, A; Cattori, Valentino; Bachler, Barbara; Hartnack, Sonja; Riond, Barbara; Ossent, Pete; Lutz, Hans; Hofmann-Lehmann, Regina

    2011-12-01

    Virus receptors and their expression patterns on the cell surface determine the cell tropism of the virus, host susceptibility and the pathogenesis of the infection. Feline thiamine transport protein 1 (fTHTR1) has been identified as the receptor for feline leukemia virus (FeLV) A. The goal of the present study was to develop a quantitative, TaqMan real-time PCR assay to investigate fTHTR1 mRNA expression in tissues of uninfected and FeLV-infected cats, cats of different ages, in tumor tissues and leukocyte subsets. Moreover, the receptor was molecularly characterized in different feline species. fTHTR1 mRNA expression was detected in all 30 feline tissues investigated, oral mucosa scrapings and blood. Importantly, identification of significant differences in fTHTR1 expression relied on normalization with an appropriate reference gene. The lowest levels were found in the blood, whereas high levels were measured in the oral mucosa, salivary glands and the musculature. In the blood, T lymphocytes showed significantly higher fTHTR1 mRNA expression levels than neutrophil granulocytes. In vitro activation of peripheral blood mononuclear cells with concanavalin A alone or followed by interleukin-2 led to a transient increase of fTHTR1 mRNA expression. In the blood, but not in the examined tissues, FeLV-infected cats tended to have lower fTHTR1 mRNA levels than uninfected cats. The fTHTR1 mRNA levels were not significantly different between tissues with lymphomas and the corresponding non-neoplastic tissues. fTHTR1 was highly conserved among different feline species (Iberian lynx, Asiatic and Indian lion, European wildcat, jaguarundi, domestic cat). In conclusion, while ubiquitous fTHTR1 mRNA expression corresponded to the broad target tissue range of FeLV, particularly high fTHTR1 levels were found at sites of virus entry and shedding. The differential susceptibility of different species to FeLV could not be attributed to variations in the fTHTR1 sequence. Copyright

  13. Challenges to the development of vaccines to hepatitis C virus that elicit neutralizing antibodies.

    Directory of Open Access Journals (Sweden)

    Heidi Edelgard Drummer

    2014-07-01

    Full Text Available Despite 20 years of research, a vaccine to prevent hepatitis C virus (HCV infection has not been developed. A vaccine to prevent HCV will need to induce broadly reactive immunity able to prevent infection by the 7 genetically and antigenically distinct genotypes circulating world-wide. Hepatitis C virus encodes two surface exposed glycoproteins, E1 and E2 that function as a heterodimer to mediate viral entry. Neutralizing antibodies (NAbs to both E1 and E2 have been described with the major NAb target being E2. The function of E2 is to attach virions to host cells via cell surface receptors that include, but is not limited to, the tetraspanin CD81 and scavenger receptor B class I. However, E2 has developed a number of immune evasion strategies to limit the effectiveness of the NAb response and possibly limit the ability of the immune system to generate potent NAbs in natural infection. Hypervariable regions that shield the underlying core domain, subdominant neutralization epitopes and glycan shielding combine to make E2 a difficult target for the immune system. This review summarizes recent information on the role of neutralizing antibodies to prevent HCV infection, the targets of the neutralizing antibody response and structural information on glycoprotein E2 in complex with neutralizing antibodies. This new information should provide a framework for the rational design of new vaccine candidates that elicit highly potent broadly reactive NAbs to prevent HCV infection.

  14. Characterization of antibody response in neuroinvasive infection caused by Toscana virus.

    Science.gov (United States)

    Pierro, A; Ficarelli, S; Ayhan, N; Morini, S; Raumer, L; Bartoletti, M; Mastroianni, A; Prati, F; Schivazappa, S; Cenni, P; Vocale, C; Rossini, G; Gaibani, P; Sambri, V; Landini, M P; Lewis, R E; Charrel, R N; Varani, S

    2017-11-01

    Among sandfly-borne pathogens, Toscana virus (TOSV) is a prominent cause of summer meningitis in Mediterranean Europe. Here, we assessed the kinetics of anti-TOSV antibodies over time in 41 patients diagnosed with TOSV meningitis or meningoencephalitis in northeastern Italy. Acute and follow-up serum samples were collected up to 20 months after diagnosis of TOSV infection and tested for the presence of specific antibody using immunoenzymatic and indirect immunofluorescence assays. In addition, maturation of anti-TOSV IgG over time was evaluated as well as production of neutralizing antibodies. Specific IgM and IgG response was present at diagnosis in 100% of patients; TOSV-specific IgM and IgG were detected in patients' sera up to 6 and 20 months after diagnosis, respectively. The avidity index (AI) increased over the first month after infection in 100% of patients and most cases exceeded 60% by Day 30 post infection. The AI subsequently plateaued then declined at 20 months after diagnosis. Finally, neutralization assay to TOSV was performed in 217 sera collected from 41 patients; 69.6% of tested samples resulted in reactive and moderate levels of neutralizing antibodies observed during all phases of infection despite high titres of total anti-TOSV IgG. Specific antibody response develops rapidly and is long-lasting for neuroinvasive TOSV infection. Serodiagnosis of neuroinvasive TOSV requires simultaneous detection of specific IgM and IgG. Moderate levels of neutralizing antibodies were maintained over the study period, while the protective role of antibodies lacking neutralizing activity is unclear and requires further evaluation. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  15. Elevation of blood levels of zinc protoporphyrin by radiomimetic drugs and friend leukemia virus

    International Nuclear Information System (INIS)

    Walden, T.L.; Al-Ansari, H.M.; Farkas, W.R.; Tennessee Univ., Knoxville; Tennessee Univ., Knoxville

    1987-01-01

    Sublethal doses of whole-body irradiation induced the elevation of zinc protoporphyrin (ZPP). Experiments were conducted to determine if recovery from radiomimetic drugs also resulted in elevation of ZPP. Daily injections with hydroxyurea and other cytotoxic drugs for 10 days caused ZPP elevation and a dose of radiation too low to cause ZPP elevation by itself caused ZPP elevation when hydroxyurea was administered prior to irradiation. Friend leukemia virus also brought about an elevation of ZPP. However, not all factors that increased erythropoiesis brought about ZPP elevation. The elevated erythropoiesis in response to hypoxia and the enhanced erythropoiesis that followed administration of folic acid to folic acid-deficient mice was not accompanied by ZPP elevation. (orig.)

  16. Elevation of blood levels of zinc protoporphyrin by radiomimetic drugs and friend leukemia virus

    Energy Technology Data Exchange (ETDEWEB)

    Walden, T.L.; Al-Ansari, H.M.; Farkas, W.R.

    1987-01-01

    Sublethal doses of whole-body irradiation induced the elevation of zinc protoporphyrin (ZPP). Experiments were conducted to determine if recovery from radiomimetic drugs also resulted in elevation of ZPP. Daily injections with hydroxyurea and other cytotoxic drugs for 10 days caused ZPP elevation and a dose of radiation too low to cause ZPP elevation by itself caused ZPP elevation when hydroxyurea was administered prior to irradiation. Friend leukemia virus also brought about an elevation of ZPP. However, not all factors that increased erythropoiesis brought about ZPP elevation. The elevated erythropoiesis in response to hypoxia and the enhanced erythropoiesis that followed administration of folic acid to folic acid-deficient mice was not accompanied by ZPP elevation.

  17. Increase of cells expressing PD-L1 in bovine leukemia virus infection and enhancement of anti-viral immune responses in vitro via PD-L1 blockade

    Directory of Open Access Journals (Sweden)

    Ikebuchi Ryoyo

    2011-09-01

    Full Text Available Abstract The inhibitory receptor programmed death-1 (PD-1 and its ligand, programmed death-ligand 1 (PD-L1 are involved in immune evasion mechanisms for several pathogens causing chronic infections. Blockade of the PD-1/PD-L1 pathway restores anti-virus immune responses, with concomitant reduction in viral load. In a previous report, we showed that, in bovine leukemia virus (BLV infection, the expression of bovine PD-1 is closely associated with disease progression. However, the functions of bovine PD-L1 are still unknown. To investigate the role of PD-L1 in BLV infection, we identified the bovine PD-L1 gene, and examined PD-L1 expression in BLV-infected cattle in comparison with uninfected cattle. The deduced amino acid sequence of bovine PD-L1 shows high homology to the human and mouse PD-L1. The proportion of PD-L1 positive cells, especially among B cells, was upregulated in cattle with the late stage of the disease compared to cattle at the aleukemic infection stage or uninfected cattle. The proportion of PD-L1 positive cells correlated positively with prediction markers for the progression of the disease such as leukocyte number, virus load and virus titer whilst on the contrary, it inversely correlated with the degree of interferon-gamma expression. Blockade of the PD-1/PD-L1 pathway in vitro by PD-L1-specific antibody upregulated the production of interleukin-2 and interferon-gamma, and correspondingly, downregulated the BLV provirus load and the proportion of BLV-gp51 expressing cells. These data suggest that PD-L1 induces immunoinhibition in disease progressed cattle during chronic BLV infection. Therefore, PD-L1 would be a potential target for developing immunotherapies against BLV infection.

  18. Isotypes of Epstein-Barr Virus Antibodies in Rheumatoid Arthritis: Association with Rheumatoid Factors and Citrulline-Dependent Antibodies

    Directory of Open Access Journals (Sweden)

    Marie Wulff Westergaard

    2015-01-01

    Full Text Available In order to study the humoral immune response against Epstein-Barr virus (EBV in patients with rheumatoid arthritis (RA and to compare it with the two major autoantibody types in RA, plasma samples from 77 RA patients, 28 patients with systemic lupus erythematosus (SLE, and 28 healthy controls (HCs were investigated by enzyme-linked immunosorbent assays (ELISA. Increased percentages of positives and concentrations of IgG/IgA/IgM antibodies against the latent EBV nuclear antigen-1 (EBNA-1 were observed in RA patients compared to SLE patients and HCs. Increased concentrations and percentages of positives of IgG/IgA/IgM against the early lytic EBV antigen diffuse (EAD were also found in RA patients compared to HCs but were highest in SLE patients. Furthermore, associations between the elevated EBNA-1 IgA and EBNA-1 IgM levels and the presence of IgM and IgA rheumatoid factors (RFs and anti-citrullinated protein antibodies (ACPAs, IgG and between elevated IgA concentrations against EAD and the presence of RFs and ACPAs in RA patients were found. Thus, RA patients had elevated antibodies of all isotypes characteristic of latent EBV infection (whereas SLE patients had elevated antibodies characteristic of lytic EBV infection. Notably, for IgM and IgA (but not IgG, these were associated with the presence of characteristic RA autoantibodies.

  19. Identifying the Conditions Under Which Antibodies Protect Against Infection by Equine Infectious Anemia Virus

    Directory of Open Access Journals (Sweden)

    Elissa J. Schwartz

    2014-05-01

    Full Text Available The ability to predict the conditions under which antibodies protect against viral infection would transform our approach to vaccine development. A more complete understanding is needed of antibody protection against lentivirus infection, as well as the role of mutation in resistance to an antibody vaccine. Recently, an example of antibody-mediated vaccine protection has been shown via passive transfer of neutralizing antibodies before equine infectious anemia virus (EIAV infection of horses with severe combined immunodeficiency (SCID. Viral dynamic modeling of antibody protection from EIAV infection in SCID horses may lead to insights into the mechanisms of control of infection by antibody vaccination. In this work, such a model is constructed in conjunction with data from EIAV infection of SCID horses to gain insights into multiple strain competition in the presence of antibody control. Conditions are determined under which wild-type infection is eradicated with the antibody vaccine. In addition, a three-strain competition model is considered in which a second mutant strain may coexist with the first mutant strain. The conditions that permit viral escape by the mutant strains are determined, as are the effects of variation in the model parameters. This work extends the current understanding of competition and antibody control in lentiviral infection, which may provide insights into the development of vaccines that stimulate the immune system to control infection effectively.

  20. Epitope Sequences in Dengue Virus NS1 Protein Identified by Monoclonal Antibodies

    Directory of Open Access Journals (Sweden)

    Leticia Barboza Rocha

    2017-10-01

    Full Text Available Dengue nonstructural protein 1 (NS1 is a multi-functional glycoprotein with essential functions both in viral replication and modulation of host innate immune responses. NS1 has been established as a good surrogate marker for infection. In the present study, we generated four anti-NS1 monoclonal antibodies against recombinant NS1 protein from dengue virus serotype 2 (DENV2, which were used to map three NS1 epitopes. The sequence 193AVHADMGYWIESALNDT209 was recognized by monoclonal antibodies 2H5 and 4H1BC, which also cross-reacted with Zika virus (ZIKV protein. On the other hand, the sequence 25VHTWTEQYKFQPES38 was recognized by mAb 4F6 that did not cross react with ZIKV. Lastly, a previously unidentified DENV2 NS1-specific epitope, represented by the sequence 127ELHNQTFLIDGPETAEC143, is described in the present study after reaction with mAb 4H2, which also did not cross react with ZIKV. The selection and characterization of the epitope, specificity of anti-NS1 mAbs, may contribute to the development of diagnostic tools able to differentiate DENV and ZIKV infections.

  1. Comparison of the cross-antibody response induced in sheep by inactivated bovine viral diarrhoea virus 1 and Hobi-like pestivirus.

    Science.gov (United States)

    Decaro, Nicola; Mari, Viviana; Sciarretta, Rossana; Lucente, Maria Stella; Camero, Michele; Losurdo, Michele; Larocca, Vittorio; Colao, Valeriana; Cavaliere, Nicola; Lovero, Angela; Lorusso, Eleonora; Buonavoglia, Canio

    2013-06-01

    Hobi-like pestivirus, a new tentative species within genus Pestivirus, was firstly detected in foetal bovine serum batches and later associated to respiratory distress and reproductive failures in cattle. In the present study, the cross-antibody response between bovine viral diarrhoea virus 1 (BVDV-1) and the emerging pestivirus was evaluated in the sheep model. Ten sheep were immunised against BVDV-1 or Hobi-like pestivirus using inactivated preparations and the induced antibody responses were evaluated against the homologous and heterologous viruses. The results showed that heterologous antibody titres were significantly lower than the homologous ones, thus suggesting the need to develop specific vaccines against the emerging pestiviral species. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Voltage-Gated Potassium Channel Antibody Paraneoplastic Limbic Encephalitis Associated with Acute Myeloid Leukemia

    Directory of Open Access Journals (Sweden)

    Marion Alcantara

    2013-05-01

    Full Text Available Among paraneoplastic syndromes (PNS associated with malignant hemopathies, there are few reports of PNS of the central nervous system and most of them are associated with lymphomas. Limbic encephalitis is a rare neurological syndrome classically diagnosed in the context of PNS. We report the case of a 81-year-old man who presented with a relapsed acute myeloid leukemia (AML with minimal maturation. He was admitted for confusion with unfavorable evolution as he presented a rapidly progressive dementia resulting in death. A brain magnetic resonance imaging, performed 2 months after the onset, was considered normal. An electroencephalogram showed non-specific bilateral slow waves. We received the results of the blood screening of neuronal autoantibodies after the patient's death and detected the presence of anti-voltage-gated potassium channel (VGKC antibodies at 102 pmol/l (normal at <30 pmol/l. Other etiologic studies, including the screening for another cause of rapidly progressive dementia, were negative. To our knowledge, this is the first case of anti-VGKC paraneoplastic limbic encephalitis related to AML.

  3. Complete suppression of viral gene expression is associated with the onset and progression of lymphoid malignancy: observations in Bovine Leukemia Virus-infected sheep

    Directory of Open Access Journals (Sweden)

    Burny Arsène

    2007-07-01

    Full Text Available Abstract Background During malignant progression, tumor cells need to acquire novel characteristics that lead to uncontrolled growth and reduced immunogenicity. In the Bovine Leukemia Virus-induced ovine leukemia model, silencing of viral gene expression has been proposed as a mechanism leading to immune evasion. However, whether proviral expression in tumors is completely suppressed in vivo was not conclusively demonstrated. Therefore, we studied viral expression in two selected experimentally-infected sheep, the virus or the disease of which had features that made it possible to distinguish tumor cells from their nontransformed counterparts. Results In the first animal, we observed the emergence of a genetically modified provirus simultaneously with leukemia onset. We found a Tax-mutated (TaxK303 replication-deficient provirus in the malignant B-cell clone while functional provirus (TaxE303 had been consistently monitored over the 17-month aleukemic period. In the second case, both non-transformed and transformed BLV-infected cells were present at the same time, but at distinct sites. While there was potentially-active provirus in the non-leukemic blood B-cell population, as demonstrated by ex-vivo culture and injection into naïve sheep, virus expression was completely suppressed in the malignant B-cells isolated from the lymphoid tumors despite the absence of genetic alterations in the proviral genome. These observations suggest that silencing of viral genes, including the oncoprotein Tax, is associated with tumor onset. Conclusion Our findings suggest that silencing is critical for tumor progression and identify two distinct mechanisms-genetic and epigenetic-involved in the complete suppression of virus and Tax expression. We demonstrate that, in contrast to systems that require sustained oncogene expression, the major viral transforming protein Tax can be turned-off without reversing the transformed phenotype. We propose that suppression

  4. Prevalence of Avian Origin H5 and H7 Influenza Virus Antibodies in ...

    African Journals Online (AJOL)

    As part of ongoing influenza surveillance efforts in livestock and companion animals in Nigeria, a study was conducted to investigate the prevalence of avian H5 and H7 influenza virus antibodies in exotic and Nigerian village dogs in Ibadan and Sagamu, two cities in Oyo and Ogun states respectively. One hundred and ...

  5. Experiments toward the development of a radioimmunoassay for the detection of serum antibodies for the respiratory syncytial virus

    International Nuclear Information System (INIS)

    Heizmann, W.R.

    1982-01-01

    In order to detect an infection by the respiratory syncytial virus (RSV) quickly and safely, a radioimmunassay (RIA) should be developed. Various antigen preparations were compared to one another. The immune serums used in the RIA came from guinea pigs with a RSV antibody titer of up to 320 in the complement binding reaction. A number of observations lead to the discussion of the possibility of the formation (incomplete) of cross-reactive antibodies between virus and host cell. This hypothesis could be well supported through references in the literature. Under the assumption of the existence of cross-reactive antibodies, a further model of the pathogenesis of the RSV illness allows itself to be developed, which could be preceived as an illness with autoimmune components. With this model the varying courses of this disease in different age groups can be easily explained. (orig.) [de

  6. THE THEORETICAL AND PRACTICAL ASPECTS OF THE RECOMBINANT ANTIGENS FOR THE DIAGNOSIS OF BOVINE LEUKEMIA PRODUCTION

    Directory of Open Access Journals (Sweden)

    Shapovalova OV

    2016-12-01

    Full Text Available Introduction. Nowadays the problem of bovine leukemia (EBL effective diagnosis in countries where EBL is registered and the disease-free areas remains actual. The main diagnostic tests are immunodiffusion reaction (AGID and enzyme-linked immunosorbent assay (ELISA, which allow the identification of infected animals by the presence of antibodies to bovine leukemia virus (BLV both in serum and in milk samples. The effectiveness of these methods depends on the quality of diagnostic test systems used and determines by the cultural and recombinant virus antigens specificity. EBL recombinant antigens have certain advantages as they are more active and cheap. Purpose of the work. The analysis of theoretical and practical approaches in the bovine leukemia virus recombinant antigens development and its diagnostic potential evaluation. The article contains data from the literature on the recombinant antigens of bovine leukemia virus construction and use. Analysis of the literature showed that the recombinant proteins are widely used in the serological diagnosis of bovine leukemia. Numerous protocols of BLV gp51 and p24 immunodominant antigens preparation has been developed in heterologous systems (Saccharomyces cerevisiae, E. coli, vaccinia virus, baculovirus. In order to obtain recombinant antigens, the BLV provirus genome regions isolated from FLK-BLV cell culture, lymphocytes or tumor cells from naturally infected cattle are typically used. For the recombinant antigens labeled by hexahistidine or Srept II purification one-step immobilized-metal affinity chromatography IMAC and highly selective Strep-Tactin affinity chromatography methods are carried out. The end products activity and specificity are studied in the immunoblotting, ELISA and AGID diagnostic reactions. The ukrainian scientists’ publications are devoted to the clone E. coli HB101-2 transformed by the recombinant plasmid containing fully functional BLV env and gag genes nucleotide

  7. Fidelity of target site duplication and sequence preference during integration of xenotropic murine leukemia virus-related virus.

    Directory of Open Access Journals (Sweden)

    Sanggu Kim

    Full Text Available Xenotropic murine leukemia virus (MLV-related virus (XMRV is a new human retrovirus associated with prostate cancer and chronic fatigue syndrome. The causal relationship of XMRV infection to human disease and the mechanism of pathogenicity have not been established. During retrovirus replication, integration of the cDNA copy of the viral RNA genome into the host cell chromosome is an essential step and involves coordinated joining of the two ends of the linear viral DNA into staggered sites on target DNA. Correct integration produces proviruses that are flanked by a short direct repeat, which varies from 4 to 6 bp among the retroviruses but is invariant for each particular retrovirus. Uncoordinated joining of the two viral DNA ends into target DNA can cause insertions, deletions, or other genomic alterations at the integration site. To determine the fidelity of XMRV integration, cells infected with XMRV were clonally expanded and DNA sequences at the viral-host DNA junctions were determined and analyzed. We found that a majority of the provirus ends were correctly processed and flanked by a 4-bp direct repeat of host DNA. A weak consensus sequence was also detected at the XMRV integration sites. We conclude that integration of XMRV DNA involves a coordinated joining of two viral DNA ends that are spaced 4 bp apart on the target DNA and proceeds with high fidelity.

  8. H7N9 Avian Influenza Virus Is Efficiently Transmissible and Induces an Antibody Response in Chickens

    Directory of Open Access Journals (Sweden)

    Peirong Jiao

    2018-04-01

    Full Text Available H7N9 viruses pose a threat to human health and they are no less harmful to the poultry industry than the H5N1 avian influenza viruses. However, the pathogenesis, transmissibility, and the host immune response of the H7N9 virus in chickens and mice remain unclear. In this study, we found that H7N9 viruses replicated in multiple organs of the chicken and viral shedding persisted up to 30 days postinoculation (DPI. The viruses were efficiently transmitted between chickens through direct contact. Notably, chickens infected with H7N9 had high antibody levels throughout the entire observation period and their antibody response lasted for 30 DPI. The expression levels of the pattern-recognition receptors and pro-inflammatory cytokines were found to be significantly upregulated in the brain using quantitative real-time PCR. The expression of TLR3, TLR7, MDA5, Mx, IL-1β, IL-6, IFN-α, and IFN-γ were also significantly different in the lungs of infected chickens. We found that the viruses isolated from these birds had low pathogenicity in mice, produced little weight loss and could only replicate in the lungs. Our findings suggested that the H7N9 viruses could replicate in chickens and mice and be efficiently transmitted between chickens, which presented a significant threat to human and poultry health.

  9. Seroprevalence immunodeficiency virus and feline leukemia in cats in Monteria, Córdoba SEROPREVALENCIA DEL VIRUS DE LEUCEMIA E INMUNODEFICIENCIA FELINA EN GATOS DE MONTERÍA, CÓRDOBA

    OpenAIRE

    Ríos Rincón Rodrigo Alexander; Álvarez Arrieta Leonardo; Sánchez García Alba Eugenia; Tique Salleg Vaneza Paulin; Mattar Velilla Salim

    2009-01-01

    The gradual increment of the feline population in Colombia and some countries is associated with presence of diseases that care produce animal health risk. The virus of immunodeficiency and the feline leukemia are the main retroviales diseases with high morbility and mortality in felines and they require of a right diagnostic that extend the felines’ life. A descriptive transversal cut study was done, 60 urban domestic cats of Montería were included, animals were from clinics, veterinarian co...

  10. Occurrence of West Nile Virus Antibodies in Wild Birds, Horses, and Humans in Poland

    Directory of Open Access Journals (Sweden)

    Jowita Samanta Niczyporuk

    2015-01-01

    Full Text Available Serum samples of 474 wild birds, 378 horses, and 42 humans with meningitis and lymphocytic meningitis were collected between 2010 and 2014 from different areas of Poland. West Nile virus (WNV antibodies were detected using competition enzyme linked immunosorbent assays: ELISA-1 ID Screen West Nile Competition, IDvet, ELISA-2 ID Screen West Nile IgM Capture, and ELISA-3 Ingezim West Nile Compac. The antibodies were found in 63 (13.29% out of 474 wild bird serum samples and in one (0.26% out of 378 horse serum samples. Fourteen (33.33% out of 42 sera from patients were positive against WNV antigen and one serum was doubtful. Positive samples obtained in birds were next retested with virus microneutralisation test to confirm positive results and cross-reactions with other antigens of the Japanese encephalitis complex. We suspect that positive serological results in humans, birds, and horses indicate that WNV can be somehow closely related with the ecosystem in Poland.

  11. The increased susceptibility of hematopoietic stem cells to Friend leukemia virus in the repopulating period

    International Nuclear Information System (INIS)

    Hirashima, Kunitake; Kumatori, Toshiyuki

    1977-01-01

    The present study considers two fundamental problems of leukemia and stem cells: (1) whether the target cells for malignant transformation of Friend leukemia virus (FV) are the pluripotential stem cells; (2) whether the susceptibility of the target cell is changeable depending on the proliferating state of the cell. In the experiments, inbred 8- to 12-week-old C3H/He and BC3Fl hybrid mice were used. As target cells for FV, two candidate cell populations should be considered. These are the pluripotential stem cells expressed as CFUs and the committed stem cells expressed as erythropoietin-responsive cells (ERC). According to our preliminary experiments on the recovery patterns of CFUs or ERC, after a single 150 rads X-irradiation (X) or administration of 215 mg/kg of cyclophosphamide (CY), it was clear that the repopulation of CFUs was quite different from that of ERC. The target cells for FV-induced transformation are the stem cells expressed as CFUs and the susceptibility of these increases under conditions of active repopulation after X-irradiation and cyclophosphamide administration. After the irradiation especially, this effect is dose-dependent for doses over 25 rads at 2 weeks after irradiation. (Auth.)

  12. Fetal demise and failed antibody therapy during Zika virus infection of pregnant macaques.

    Science.gov (United States)

    Magnani, Diogo M; Rogers, Thomas F; Maness, Nicholas J; Grubaugh, Nathan D; Beutler, Nathan; Bailey, Varian K; Gonzalez-Nieto, Lucas; Gutman, Martin J; Pedreño-Lopez, Núria; Kwal, Jaclyn M; Ricciardi, Michael J; Myers, Tereance A; Julander, Justin G; Bohm, Rudolf P; Gilbert, Margaret H; Schiro, Faith; Aye, Pyone P; Blair, Robert V; Martins, Mauricio A; Falkenstein, Kathrine P; Kaur, Amitinder; Curry, Christine L; Kallas, Esper G; Desrosiers, Ronald C; Goldschmidt-Clermont, Pascal J; Whitehead, Stephen S; Andersen, Kristian G; Bonaldo, Myrna C; Lackner, Andrew A; Panganiban, Antonito T; Burton, Dennis R; Watkins, David I

    2018-04-24

    Zika virus (ZIKV) infection of pregnant women is associated with pathologic complications of fetal development. Here, we infect pregnant rhesus macaques (Macaca mulatta) with a minimally passaged ZIKV isolate from Rio de Janeiro, where a high rate of fetal development complications was observed. The infection of pregnant macaques with this virus results in maternal viremia, virus crossing into the amniotic fluid (AF), and in utero fetal deaths. We also treated three additional ZIKV-infected pregnant macaques with a cocktail of ZIKV-neutralizing human monoclonal antibodies (nmAbs) at peak viremia. While the nmAbs can be effective in clearing the virus from the maternal sera of treated monkeys, it is not sufficient to clear ZIKV from AF. Our report suggests that ZIKV from Brazil causes fetal demise in non-human primates (NHPs) without additional mutations or confounding co-factors. Treatment with a neutralizing anti-ZIKV nmAb cocktail is insufficient to fully stop vertical transmission.

  13. Antibody-mediated neutralization of Ebola virus can occur by two distinct mechanisms

    International Nuclear Information System (INIS)

    Shedlock, Devon J.; Bailey, Michael A.; Popernack, Paul M.; Cunningham, James M.; Burton, Dennis R.; Sullivan, Nancy J.

    2010-01-01

    Human Ebola virus causes severe hemorrhagic fever disease with high mortality and there is no vaccine or treatment. Antibodies in survivors occur early, are sustained, and can delay infection when transferred into nonhuman primates. Monoclonal antibodies (mAbs) from survivors exhibit potent neutralizing activity in vitro and are protective in rodents. To better understand targets and mechanisms of neutralization, we investigated a panel of mAbs shown previously to react with the envelope glycoprotein (GP). While one non-neutralizing mAb recognized a GP epitope in the nonessential mucin-like domain, the rest were specific for GP1, were neutralizing, and could be further distinguished by reactivity with secreted GP. We show that survivor antibodies, human KZ52 and monkey JP3K11, were specific for conformation-dependent epitopes comprising residues in GP1 and GP2 and that neutralization occurred by two distinct mechanisms; KZ52 inhibited cathepsin cleavage of GP whereas JP3K11 recognized the cleaved, fusion-active form of GP.

  14. Broad neutralizing human monoclonal antibodies against influenza virus from vaccinated healthy donors

    Energy Technology Data Exchange (ETDEWEB)

    Kubota-Koketsu, Ritsuko; Mizuta, Hiroyuki [Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871 (Japan); Oshita, Masatoshi; Ideno, Shoji [Osaka Research Laboratory, Benesis Corporation, Yodogawa-ku, Osaka 532-6505 (Japan); Yunoki, Mikihiro [Osaka Research Laboratory, Benesis Corporation, Yodogawa-ku, Osaka 532-6505 (Japan); Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871 (Japan); Kuhara, Motoki [Ina Laboratory, Medical and Biological Laboratories Corporation, Ltd., Ina, Nagano 396-0002 (Japan); Yamamoto, Naomasa [Department of Biochemistry, School of Pharmaceutical Sciences, Ohu University, Koriyama, Fukushima 963-8611 (Japan); Okuno, Yoshinobu [Kanonji Institute, The Research Foundation for Microbial Diseases of Osaka University, Kanonji, Kagawa 768-0061 (Japan); Ikuta, Kazuyoshi, E-mail: ikuta@biken.osaka-u.ac.jp [Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871 (Japan)

    2009-09-11

    Human monoclonal antibodies (HuMAbs) prepared from patients with viral infections could provide information on human epitopes important for the development of vaccines as well as potential therapeutic applications. Through the fusion of peripheral blood mononuclear cells from a total of five influenza-vaccinated volunteers, with newly developed murine-human chimera fusion partner cells, named SPYMEG, we obtained 10 hybridoma clones stably producing anti-influenza virus antibodies: one for influenza A H1N1, four for influenza A H3N2 and five for influenza B. Surprisingly, most of the HuMAbs showed broad reactivity within subtype and four (two for H3N2 and two for B) showed broad neutralizing ability. Importantly, epitope mapping revealed that the two broad neutralizing antibodies to H3N2 derived from different donors recognized the same epitope located underneath the receptor-binding site of the hemagglutinin globular region that is highly conserved among H3N2 strains.

  15. Broad neutralizing human monoclonal antibodies against influenza virus from vaccinated healthy donors

    International Nuclear Information System (INIS)

    Kubota-Koketsu, Ritsuko; Mizuta, Hiroyuki; Oshita, Masatoshi; Ideno, Shoji; Yunoki, Mikihiro; Kuhara, Motoki; Yamamoto, Naomasa; Okuno, Yoshinobu; Ikuta, Kazuyoshi

    2009-01-01

    Human monoclonal antibodies (HuMAbs) prepared from patients with viral infections could provide information on human epitopes important for the development of vaccines as well as potential therapeutic applications. Through the fusion of peripheral blood mononuclear cells from a total of five influenza-vaccinated volunteers, with newly developed murine-human chimera fusion partner cells, named SPYMEG, we obtained 10 hybridoma clones stably producing anti-influenza virus antibodies: one for influenza A H1N1, four for influenza A H3N2 and five for influenza B. Surprisingly, most of the HuMAbs showed broad reactivity within subtype and four (two for H3N2 and two for B) showed broad neutralizing ability. Importantly, epitope mapping revealed that the two broad neutralizing antibodies to H3N2 derived from different donors recognized the same epitope located underneath the receptor-binding site of the hemagglutinin globular region that is highly conserved among H3N2 strains.

  16. Mutational library analysis of selected amino acids in the receptor binding domain of envelope of Akv murine leukemia virus by conditionally replication competent bicistronic vectors

    DEFF Research Database (Denmark)

    Bahrami, Shervin; Jespersen, Thomas; Pedersen, Finn Skou

    2003-01-01

    The envelope protein of retroviruses is responsible for viral entry into host cells. Here, we describe a mutational library approach to dissect functional domains of the envelope protein involving a retroviral vector, which expresses both the envelope protein of Akv murine leukemia virus (MLV) an...

  17. Antibodies against Severe Fever with Thrombocytopenia Syndrome Virus in Healthy Persons, China, 2013

    Science.gov (United States)

    Zhang, Lei; Sun, Jimin; Yan, Jie; Lv, Huakun; Chai, Chengliang; Sun, Yi; Shao, Bin; Jiang, Jianmin; Chen, Zhiping

    2014-01-01

    In June 2013, a subclinical infection with severe fever with thrombocytopenia syndrome virus (SFTSV) was detected in Zhejiang Province, China, prompting seroprevalence studies in 6 districts within the province. Of 986 healthy persons tested, 71 had IgG antibodies against SFTSV. This finding suggests that most natural infections with SFTSV are mild or subclinical. PMID:25061813

  18. Detection of Schmallenberg virus antibody in equine population of Northern and Northeast of Iran

    Directory of Open Access Journals (Sweden)

    M. Rasekh

    2018-01-01

    Full Text Available Aim: Schmallenberg virus (SBV is a newly emerging virus in Simbu group that 1st time is reported in 2011 in Germany and now spread to Europe. The clinical signs of infection to this virus are fever, loss of appetite, reduced milk yield and in some cases, diarrhea and in pregnant animals congenital malformations in calves, lambs, and kid goats. Materials and Methods: In this study for a serologic survey of SBV, blood samples from 200 horse in different rural areas of the northern and northeast of Iran with the high equine population collected and were analyzed using an indirect ELISA test. Results: Based on our results 5% (n=10 of total 200 samples were positive for SBV antibody and 2% (n=4 was doubtful and 93% (n=186 was negative. There were no significant differences between age and sex and breed properties (p>0.05. Conclusion: This study demonstrated the presence of antibodies against the SBV on horse populations in Iran. The high population and activity of Culicoides biting midges and their proper living conditions, especially the areas of temperate and humid environmental conditions, are the possible causes of arboviruses related diseases seen in this country.

  19. Relation of type-C RNA virus infectivity and leukemogenesis in rats and mice

    International Nuclear Information System (INIS)

    Nagao, Kenji; Ito, Takaaki; Yokoro, Kenjiro

    1976-01-01

    Observation was made as to movement of type-C RNA virus infectivity in the process of leukemogensis induced by Gross virus, N-nitrosoethylurea (NEU), or, x-ray. Total dose of 680 R in 4 times was given to the whole body or parts of the body at intervals of 5 days. Thymic leukemia occurred in 100% or rats which were inoculated with type-C RNA virus at the period of newborn 64 days after, on the average. Infectious titer of virus rose only in thymus toward leukemogenesis. Thymic leukemia was induced 100% in mice by NEU 122 days after, but its incidence was 9% of mice of which thymus was extracted. Leukemia virus was not detected in non-extracted thymus of mice, and pattern of virus infectivity in other organs did not show any difference with that of mice of which thymus was extracted. Virus showed high infectious titer in uterus of mice of both groups. Leukemia occurred 87% in the whole body irradiated mice, 15% in partially irradiated mice, and 39% in mice of which thymus was extracted and the whole body was irradiated. Virus did not show any homeostatic infectious titer in three kinds of leukemia, but it showed high infectious titer in uterus. (Kanao, N.)

  20. Human T-lymphotropic virus type-I infection, antibody titers and cause-specific mortality among atomic-bomb survivors

    Energy Technology Data Exchange (ETDEWEB)

    Arisawa, Kokichi; Soda, Midori; Akahoshi, Masazumi [Radiation Effects Research Foundation, Nagasaki (Japan). Nagasaki Lab.; Matsuo, Tatsuki; Nakashima, Eiji; Tomonaga, Masao; Saito, Hiroshi

    1998-08-01

    There have been few longitudinal studies on the long-term health effects of human T-lymphotropic virus type-I (HTLV-I) infection. The authors performed a cohort study of HTLV-I infection and cause-specific mortality in 3,090 atomic-bomb survivors in Nagasaki, Japan, who were followed from 1985-1987 to 1995. The prevalence of HTLV-I seropositivity in men and women was 99/1,196 (8.3%) and 171/1,894 (9.0%), respectively. During a median follow-up of 8.9 years, 448 deaths occurred. There was one nonfatal case of adult T-cell leukemia/lymphoma (incidence rate=0.46 cases/1,000 person-years; 95% confidence interval (CI) 0.01-2.6). After adjustment for sex, age and other potential confounders, significantly increased risk among HTLV-I carriers was observed for deaths from all causes (rate ratio (RR)=1.41), all cancers (RR=1.64), liver cancer (RR=3.04), and heart diseases (RR=2.22). The association of anti-HTLV-I seropositivity with mortality from all non-neoplastic diseases (RR=1.40) and chronic liver diseases (RR=5.03) was of borderline significance. Possible confounding by blood transfusions and hepatitis C/B (HCV/HBV) viral infections could not be precluded in this study. However, even after liver cancer and chronic liver diseases were excluded, mortality rate was still increased among HTLV-I carriers (RR=1.32, 95% CI 0.99-1.78), especially among those with high antibody titers (RR=1.56, 95% CI 0.99-2.46, P for trend=0.04). These findings may support the idea that HTLV-I infection exerts adverse effects on mortality from causes other than adult T-cell leukemia/lymphoma. Further studies on confounding by HCV/HBV infections and the interaction between HCV/HBV and HTLV-I may be required to analyze the increased mortality from liver cancer and chronic liver diseases. (author)

  1. Challenges for bovine viral diarrhoea virus antibody detection in bulk milk by antibody enzyme-linked immunosorbent assays due to changes in milk production levels

    DEFF Research Database (Denmark)

    Foddai, Alessandro; Enøe, Claes; Stockmarr, Anders

    2015-01-01

    Background: Bovine viral diarrhoea (BVD) is considered eradicated from Denmark. Currently, very few (if any) Danish cattle herds could be infected with BVD virus (BVDV). The Danish antibody blocking enzyme-linked immunosorbent assay (ELISA) has been successfully used during the Danish BVD eradica...

  2. SURVEILLANCE FOR ANTIBODIES AGAINST SIX CANINE VIRUSES IN WILD RACCOONS (PROCYON LOTOR) IN JAPAN.

    Science.gov (United States)

    Aoki, Emiko; Soma, Takehisa; Yokoyama, Mayumi; Matsubayashi, Makoto; Sasai, Kazumi

    2017-10-01

    Raccoons (Procyon lotor) are found worldwide. They are frequently seen in crowded inner cities as well as in forests or wooded areas, often living in proximity to humans and their pets. We examined sera from 100 wild raccoons in Japan for antibodies to six canine viruses with veterinary significance to assess their potential as reservoirs. We also aimed to understand the distribution of potentially infected wildlife. We found that 7% of samples were seropositive for canine distemper virus (CDV), 10% for canine parvovirus type 2, 2% for canine adenovirus type 1, 6% for canine adenovirus type 2, and 7% for canine coronavirus. No samples were found to be seropositive for canine parainfluenza virus. Seropositivity rates for canine distemper virus and canine parvovirus type 2 were significantly different between areas, and younger raccoons (Canis lupus familiaris), our results suggest that they can act as reservoirs for some of these important canine viruses and might be involved in viral transmission. Further study should include isolation and analysis of canine viruses in wild raccoons from a wider area.

  3. Immunophenotypical and cytomorphological examination of feline peripheral blood in patients with suspect leukemia

    Directory of Open Access Journals (Sweden)

    Serena Bernardi

    2018-06-01

    These results confirmed that T cell leukemias are more frequent than B ones in the cat with a prevalent T-helper phenotypes as previously described. AMLs were highly represented, but the lack of an adequate panel of specific antibodies for myeloid lineage rendered a high number of AUL in our caseload. Similarly, the lack of an anti-feline CD34 antibody did not permit differential diagnosis of acute leukemia vs lymphoma with blood involvement in a remarkable percentage of cases without an evident nodal enlargement and without an extreme leukocytosis.

  4. Neutralising antibody response in domestic cats immunised with a commercial feline immunodeficiency virus (FIV) vaccine.

    Science.gov (United States)

    Bęczkowski, Paweł M; Harris, Matthew; Techakriengkrai, Navapon; Beatty, Julia A; Willett, Brian J; Hosie, Margaret J

    2015-02-18

    Across human and veterinary medicine, vaccines against only two retroviral infections have been brought to market successfully, the vaccines against feline leukaemia virus (FeLV) and feline immunodeficiency virus (FIV). FeLV vaccines have been a global success story, reducing virus prevalence in countries where uptake is high. In contrast, the more recent FIV vaccine was introduced in 2002 and the degree of protection afforded in the field remains to be established. However, given the similarities between FIV and HIV, field studies of FIV vaccine efficacy are likely to advise and inform the development of future approaches to HIV vaccination. Here we assessed the neutralising antibody response induced by FIV vaccination against a panel of FIV isolates, by testing blood samples collected from client-owned vaccinated Australian cats. We examined the molecular and phenotypic properties of 24 envs isolated from one vaccinated cat that we speculated might have become infected following natural exposure to FIV. Cats vaccinated against FIV did not display broadly neutralising antibodies, suggesting that protection may not extend to some virulent recombinant strains of FIV circulating in Australia. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. Suspected myelodysplastic/myeloproliferative neoplasm in a feline leukemia virus-negative cat.

    Science.gov (United States)

    Weeden, Amy L; Taylor, Kyle R; Terrell, Scott P; Gallagher, Alexander E; Wamsley, Heather L

    2016-12-01

    A 10-year-old castrated Domestic Short-Haired cat was presented to a primary care veterinarian for a wellness examination and laboratory examination for monitoring of diabetes mellitus. The CBC revealed marked thrombocytosis, leukopenia and macrocytic, normochromic anemia. The cat tested negative for FeLV and feline immunodeficiency virus, but was positive for Mycoplasma haemominutum by PCR. Hematologic abnormalities were not responsive to therapy, so a repeat CBC and a bone marrow aspiration for cytology were performed. Additional blood smear findings included anisocytosis with megaloblastic erythroid precursors, large platelets, eosinophilic myelocytes and metamyelocytes, and rare unidentified blasts. The bone marrow smear was highly cellular, and the cytologic pattern was consistent with myelodysplastic syndrome with an erythroid predominance. At that time, 15% blasts were present. The cat was treated with a vitamin K 2 analog, doxycycline, and prednisolone, but without a clinical response. Within 3 months, euthanasia was elected due to declining quality of life, and a necropsy was performed. Postmortem bone marrow smears were highly cellular and dominated by monomorphic blasts of unknown line of origin (52%), persistent marked erythroid and megakaryocytic dysplasia, and ineffective erythropoiesis and granulopoiesis. Immunohistochemical, immunocytochemical, and cytochemical stains resulted in a diagnosis of acute myeloid leukemia of unclassified type. Additional histologic findings included mixed hepatitis with trematode infestation and lymphoplasmacytic interstitial nephritis with fibrosis. The marked thrombocytosis with myelodysplastic syndrome and the FeLV-negative status of this cat were unusual. The difficulty in classifying the myelodysplasia and subsequent leukemia highlights a need for further reporting and characterization of these types of disease. © 2016 American Society for Veterinary Clinical Pathology.

  6. Decay of maternal antibodies in broiler chickens.

    Science.gov (United States)

    Gharaibeh, Saad; Mahmoud, Kamel

    2013-09-01

    The objective of this study was to determine the decay rate of maternal antibodies against major broiler chicken pathogens. A total of 30 one-day-old broiler chicks were obtained from a commercial hatchery and reared in isolation. These chicks were retrieved from a parent flock that received a routine vaccination program. Chicks were bled at hatch and sequentially thereafter every 5 d through 30 d of age. Maternal antibody titers were measured by ELISA for avian encephalomyelitis (AEV), avian influenza virus (AIV), chicken anemia virus (CAV), infectious bursal disease virus (IBDV), infectious bronchitis virus (IBV), infectious laryngotracheitis virus (ILTV), Mycoplasma gallisepticum (MG), Mycoplasma synoviae (MS), and reovirus (Reo). Maternal antibody titers for Newcastle disease virus (NDV) were measured using a hemagglutination inhibition test. Half-life estimates of maternal antibody titers were 5.3, 4.2, 7, 5.1, 3.9, 3.8, 4.9, 4.1, 6.3, and 4.7 d for AEV, AIV, CAV, IBDV, IBV, ILTV, MG, MS, NDV, and Reo, respectively. The statistical analysis revealed significant differences among half-lives of maternal antibody titers against certain pathogens. Furthermore, all maternal antibody titers were depleted by 10 d of age except for IBDV.

  7. Seroprevalence of Antibodies against Seal Influenza A(H10N7) Virus in Harbor Seals and Gray Seals from the Netherlands.

    Science.gov (United States)

    Bodewes, Rogier; Rubio García, Ana; Brasseur, Sophie M; Sanchez Conteras, Guillermo J; van de Bildt, Marco W G; Koopmans, Marion P G; Osterhaus, Albert D M E; Kuiken, Thijs

    2015-01-01

    In the spring and summer 2014, an outbreak of seal influenza A(H10N7) virus infection occurred among harbor seals (Phoca vitulina) off the coasts of Sweden and Denmark. This virus subsequently spread to harbor seals off the coasts of Germany and the Netherlands. While thousands of seals were reported dead in Sweden, Denmark and Germany, only a limited number of seals were found dead in the Netherlands. To determine the extent of exposure of seals in the Netherlands to influenza A/H10N7 virus, we measured specific antibody titers in serum samples from live-captured seals and seals admitted for rehabilitation in the Netherlands by use of a hemagglutination inhibition assay and an ELISA. In harbor seals in 2015, antibodies against seal influenza A(H10N7) virus were detected in 41% (32 out of 78) pups, 10% (5 out of 52) weaners, and 58% (7 out of 12) subadults or adults. In gray seals (Halichoerus grypus) in 2015, specific antibodies were not found in the pups (n = 26), but in 26% (5 out of 19) of the older animals. These findings indicate that, despite apparent low mortality, infection with seal influenza A(H10N7) virus was geographically widespread and also occurred in grey seals.

  8. Structure of the extracellular domain of matrix protein 2 of influenza A virus in complex with a protective monoclonal antibody.

    Science.gov (United States)

    Cho, Ki Joon; Schepens, Bert; Seok, Jong Hyeon; Kim, Sella; Roose, Kenny; Lee, Ji-Hye; Gallardo, Rodrigo; Van Hamme, Evelien; Schymkowitz, Joost; Rousseau, Frederic; Fiers, Walter; Saelens, Xavier; Kim, Kyung Hyun

    2015-04-01

    The extracellular domain of influenza A virus matrix protein 2 (M2e) is conserved and is being evaluated as a quasiuniversal influenza A vaccine candidate. We describe the crystal structure at 1.6 Å resolution of M2e in complex with the Fab fragment of an M2e-specific monoclonal antibody that protects against influenza A virus challenge. This antibody binds M2 expressed on the surfaces of cells infected with influenza A virus. Five out of six complementary determining regions interact with M2e, and three highly conserved M2e residues are critical for this interaction. In this complex, M2e adopts a compact U-shaped conformation stabilized in the center by the highly conserved tryptophan residue in M2e. This is the first description of the three-dimensional structure of M2e. M2e of influenza A is under investigation as a universal influenza A vaccine, but its three-dimensional structure is unknown. We describe the structure of M2e stabilized with an M2e-specific monoclonal antibody that recognizes natural M2. We found that the conserved tryptophan is positioned in the center of the U-shaped structure of M2e and stabilizes its conformation. The structure also explains why previously reported in vivo escape viruses, selected with a similar monoclonal antibody, carried proline residue substitutions at position 10 in M2. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  9. Increased carotid intima-media thickness associated with antibody responses to varicella-zoster virus and cytomegalovirus in HIV-infected patients.

    Directory of Open Access Journals (Sweden)

    Mar Masiá

    Full Text Available OBJECTIVE: We investigated the relationship of the Herpesviridiae with inflammation and subclinical atherosclerosis in HIV-infected patients. METHODS: Prospective study including virologically suppressed HIV-infected patients. IgG antibodies against herpesviruses, carotid intima-media thickness (cIMT, endothelial function through flow-mediated dilatation (FMD of the brachial artery, and blood atherosclerosis biomarkers (hsCRP, TNF-α, IL-6, MCP-1, MDA, sCD14, sCD163, VCAM-1, ICAM-1, D-dimer, and PAI-1 were measured. RESULTS: 136 patients with HIV viral load <200 copies/ml were included. 93.4% patients were infected with herpes simplex virus type-1, 55.9% with herpes simplex virus type-2, 97.1% with varicella-zoster virus, 65.4% with human herpesvirus-6, 91.2% with cytomegalovirus, and 99.3% with Epstein-Barr virus. Previous AIDS diagnosis was associated with higher cytomegalovirus IgG titers (23,000 vs 17,000 AU, P = 0.011 and higher varicella-zoster virus IgG titers (3.19 vs 2.88 AU, P = 0.047, and there was a positive correlation of the Framingham risk score with IgG levels against cytomegalovirus (Spearman's Rho 0.216, P = 0.016 and Herpes simplex virus-2 (Spearman's Rho 0.293, P = 0.001. IgG antibodies against cytomegalovirus correlated in adjusted analysis with the cIMT (P = 0.030. High seropositivity for varicella-zoster virus (OR 2.91, 95% CI 1.05-8.01, P = 0.039, and for cytomegalovirus (OR 3.79, 95% CI 1.20-11.97, P = 0.023 were predictors for the highest quartile of the cIMT in adjusted analyses. PAI-1 levels were independently associated with cytomegalovirus IgG titers (P = 0.041, IL-6 and ICAM-1 levels with varicella-zoster virus IgG (P = 0.046 and P = 0.035 respectively, and hsCRP levels with Herpes simplex virus-2 IgG (P = 0.035. CONCLUSION: In virologically suppressed HIV-infected patients, antibody responses against herpesviruses are associated with subclinical atherosclerosis, and with increased inflammation and coagulation

  10. Systemic antibodies administered by passive immunization prevent generalization of the infection by foot-and-mouth disease virus in cattle after oronasal challenge.

    Science.gov (United States)

    Barrionuevo, Florencia; Di Giacomo, Sebastián; Bucafusco, Danilo; Ayude, Andrea; Schammas, Juan; Miraglia, M Cruz; Capozzo, Alejandra; Borca, Manuel V; Perez-Filgueira, Mariano

    2018-05-01

    The role of passively transferred sera in the protection against aerogenous foot-and-mouth disease (FMD) virus infection in cattle was evaluated using vaccine-induced immune serum preparations obtained at 7 and 26 days post-vaccination (dpv). We showed that circulating antibodies were sufficient to prevent disease generalization after oronasal infection in animals passively transferred with 26-dpv serum but not with the 7-dpv serum. Conversely, conventional FMD vaccination provided clinical protection at 7 dpv, promoting fast and robust antibody responses upon challenge and even though antibody titers were similar to those found in animals passively immunized with 7-dpv serum. These results demonstrate that presence of antigen-specific antibodies is critical to prevent the dissemination of the virus within the animal. Conventional FMD vaccination additionally promoted the deployment of rapid, high titer and isotype-switched antibody responses at systemic and mucosal levels after infection, thus conferring protection even in the presence of low pre-challenge antibody titers. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Generation and Characterization of Monoclonal Antibodies against a Cyclic Variant of Hepatitis C Virus E2 Epitope 412-422

    Science.gov (United States)

    Sandomenico, Annamaria; Leonardi, Antonio; Berisio, Rita; Sanguigno, Luca; Focà, Giuseppina; Focà, Annalia; Ruggiero, Alessia; Doti, Nunzianna; Muscariello, Livio; Barone, Daniela; Farina, Claudio; Owsianka, Ania; Vitagliano, Luigi

    2016-01-01

    ABSTRACT The hepatitis C virus (HCV) E2 envelope glycoprotein is crucial for virus entry into hepatocytes. A conserved region of E2 encompassing amino acids 412 to 423 (epitope I) and containing Trp420, a residue critical for virus entry, is recognized by several broadly neutralizing antibodies. Peptides embodying this epitope I sequence adopt a β-hairpin conformation when bound to neutralizing monoclonal antibodies (MAbs) AP33 and HCV1. We therefore generated new mouse MAbs that were able to bind to a cyclic peptide containing E2 residues 412 to 422 (C-epitope I) but not to the linear counterpart. These MAbs bound to purified E2 with affinities of about 50 nM, but they were unable to neutralize virus infection. Structural analysis of the complex between C-epitope I and one of our MAbs (C2) showed that the Trp420 side chain is largely buried in the combining site and that the Asn417 side chain, which is glycosylated in E2 and solvent exposed in other complexes, is slightly buried upon C2 binding. Also, the orientation of the cyclic peptide in the antibody-combining site is rotated by 180° compared to the orientations of the other complexes. All these structural features, however, do not explain the lack of neutralization activity. This is instead ascribed to the high degree of selectivity of the new MAbs for the cyclic epitope and to their inability to interact with the epitope in more flexible and extended conformations, which recent data suggest play a role in the mechanisms of neutralization escape. IMPORTANCE Hepatitis C virus (HCV) remains a major health care burden, affecting almost 3% of the global population. The conserved epitope comprising residues 412 to 423 of the viral E2 glycoprotein is a valid vaccine candidate because antibodies recognizing this region exhibit potent neutralizing activity. This epitope adopts a β-hairpin conformation when bound to neutralizing MAbs. We explored the potential of cyclic peptides mimicking this structure to elicit

  12. Tropism, Cytotoxicity, and Inflammatory Properties of Two Envelope Genes of Murine Leukemia Virus Type-Endogenous Retroviruses of C57BL/6J Mice

    Directory of Open Access Journals (Sweden)

    Young-Kwan Lee

    2011-01-01

    Full Text Available Envelope (env proteins of certain endogenous retroviruses (ERVs participate in various pathophysiological processes. In this study, we characterized pathophysiologic properties of two murine leukemia virus-type ERV (MuLV-ERV env genes cloned from the ovary of C57BL/6J mice. The two env genes (named ENVOV1 and ENVOV2, with 1,926\\,bp coding region, originated from two MuLV-ERV loci on chromosomes 8 and 18, respectively. ENVOV1 and ENVOV2 were ~75 kDa and predominantly expressed on the cell membrane. They were capable of producing pseudotype murine leukemia virus virions. Tropism trait and infectivity of ENVOV2 were similar to the polytropic env; however, ENVOV1 had very low level of infectivity. Overexpression of ENVOV2, but not ENVOV1, exerted cytotoxic effects and induced expression of COX-2, IL-1β, IL-6, and iNOS. These findings suggest that the ENVOV1 and ENVOV2 are capable of serving as an env protein for virion assembly, and they exert differential cytotoxicity and modulation of inflammatory mediators.

  13. High prevalence of antibodies against hepatitis A virus among captive nonhuman primates.

    Science.gov (United States)

    Sa-nguanmoo, Pattaratida; Thawornsuk, Nutchanart; Rianthavorn, Pornpimol; Sommanustweechai, Angkana; Ratanakorn, Parntep; Poovorawan, Yong

    2010-04-01

    Hepatitis A virus (HAV) can infect not only humans but also several other nonhuman primates. This study has been conducted to evaluate the comprehensive anti-HAV seroprevalence in captive nonhuman primate populations in Thailand. The prevalence of antibodies against HAV in 96 captive nonhuman primates of 11 species was evaluated by competitive enzyme immunoassay (EIA). HAV antibodies were found in 64.7% (11/17) of macaques, 85.7% (6/7) of langurs, 28.4% (10/35) of gibbons, and 94.6% (35/37) of orangutans. However, anti-HAV IgM was not found in any sera. These results indicate that the majority of captive nonhuman primates in Thailand were exposed to HAV. It is possible that some of the animals were infected prior to capture.

  14. Characterization of activating mutations of NOTCH3 in T-cell acute lymphoblastic leukemia and anti-leukemic activity of NOTCH3 inhibitory antibodies.

    Science.gov (United States)

    Bernasconi-Elias, P; Hu, T; Jenkins, D; Firestone, B; Gans, S; Kurth, E; Capodieci, P; Deplazes-Lauber, J; Petropoulos, K; Thiel, P; Ponsel, D; Hee Choi, S; LeMotte, P; London, A; Goetcshkes, M; Nolin, E; Jones, M D; Slocum, K; Kluk, M J; Weinstock, D M; Christodoulou, A; Weinberg, O; Jaehrling, J; Ettenberg, S A; Buckler, A; Blacklow, S C; Aster, J C; Fryer, C J

    2016-11-24

    Notch receptors have been implicated as oncogenic drivers in several cancers, the most notable example being NOTCH1 in T-cell acute lymphoblastic leukemia (T-ALL). To characterize the role of activated NOTCH3 in cancer, we generated an antibody that detects the neo-epitope created upon gamma-secretase cleavage of NOTCH3 to release its intracellular domain (ICD3), and sequenced the negative regulatory region (NRR) and PEST (proline, glutamate, serine, threonine) domain coding regions of NOTCH3 in a panel of cell lines. We also characterize NOTCH3 tumor-associated mutations that result in activation of signaling and report new inhibitory antibodies. We determined the structural basis for receptor inhibition by obtaining the first co-crystal structure of a NOTCH3 antibody with the NRR protein and defined two distinct epitopes for NRR antibodies. The antibodies exhibit potent anti-leukemic activity in cell lines and tumor xenografts harboring NOTCH3 activating mutations. Screening of primary T-ALL samples reveals that 2 of 40 tumors examined show active NOTCH3 signaling. We also identified evidence of NOTCH3 activation in 12 of 24 patient-derived orthotopic xenograft models, 2 of which exhibit activation of NOTCH3 without activation of NOTCH1. Our studies provide additional insights into NOTCH3 activation and offer a path forward for identification of cancers that are likely to respond to therapy with NOTCH3 selective inhibitory antibodies.

  15. Hepatitis C virus epitope exposure and neutralization by antibodies is affected by time and temperature

    DEFF Research Database (Denmark)

    Sabo, Michelle C; Luca, Vincent C; Ray, Stuart C

    2012-01-01

    A recent study with flaviviruses suggested that structural dynamics of the virion impact antibody neutralization via exposure of ostensibly cryptic epitopes. To determine whether this holds true for the distantly related hepatitis C virus (HCV), whose neutralizing epitopes may be obscured...... by a glycan shield, apolipoprotein interactions, and the hypervariable region on the E2 envelope protein, we assessed how time and temperature of pre-incubation altered monoclonal antibody (MAb) neutralization of HCV. Notably, several MAbs showed increased inhibitory activity when pre-binding was performed...

  16. Radiommunoassay of murine leukemia virus p30 using staphylococcus aureus as immunoadsorbent

    International Nuclear Information System (INIS)

    Brown, J.P.; Klitzman, J.M.; Hellstroem, E.; Washington Univ. Medical School, Seattle; Washington Univ., Seattle

    1978-01-01

    A competition radioimmunoassay for murine leukemia virus p30 has been developed. Serial dilutions of the unknown in wells of microtiter plates are incubated with 125 I-labeled p30 and goat antiserum specific for p30. Bound p30 is then removed by an immunoadsorbent specific for goat immunoglobulin, prepared from S. aureus. An internal standard of 51 Cr is used to correct for volumetric errors, the amount of the labeled p30 precipitated being calculated from the 125 I/ 51 Cr ratio of the supernatant. The assay is rapid, being completed within 2 h, precise, having a coefficient of variation less than 1%, and sensitive, being capable of detecting p30 concentrations as low as 2 ng/ml in a volume of 0.02 ml. It has been used to measure p30 levels in a series of MCA-induced fibrosarcomas of BALB/c mice. (Auth.)

  17. Conserved epitope on influenza-virus hemagglutinin head defined by a vaccine-induced antibody

    Energy Technology Data Exchange (ETDEWEB)

    Raymond, Donald D.; Bajic, Goran; Ferdman, Jack; Suphaphiphat, Pirada; Settembre, Ethan C.; Moody, M. Anthony; Schmidt, Aaron G.; Harrison, Stephen C. (Duke-MED); (CH-Boston); (Seqirus)

    2017-12-18

    Antigenic variation requires frequent revision of annual influenza vaccines. Next-generation vaccine design strategies aim to elicit a broader immunity by directing the human immune response toward conserved sites on the principal viral surface protein, the hemagglutinin (HA). We describe a group of antibodies that recognize a hitherto unappreciated, conserved site on the HA of H1 subtype influenza viruses. Mutations in that site, which required a change in the H1 component of the 2017 vaccine, had not previously “taken over” among circulating H1 viruses. Our results encourage vaccine design strategies that resurface a protein to focus the immune response on a specific region.

  18. Human T-cell leukemia virus type 2 post-transcriptional control protein p28 is required for viral infectivity and persistence in vivo.

    Science.gov (United States)

    Yamamoto, Brenda; Li, Min; Kesic, Matthew; Younis, Ihab; Lairmore, Michael D; Green, Patrick L

    2008-05-12

    Human T-cell leukemia virus (HTLV) type 1 and type 2 are related but distinct pathogenic complex retroviruses. HTLV-1 is associated with adult T-cell leukemia and a variety of immune-mediated disorders including the chronic neurological disease termed HTLV-1-associated myelopathy/tropical spastic paraparesis. In contrast, HTLV-2 displays distinct biological differences and is much less pathogenic, with only a few reported cases of leukemia and neurological disease associated with infection. In addition to the structural and enzymatic proteins, HTLV encodes regulatory (Tax and Rex) and accessory proteins. Tax and Rex positively regulate virus production and are critical for efficient viral replication and pathogenesis. Using an over-expression system approach, we recently reported that the accessory gene product of the HTLV-1 and HTLV-2 open reading frame (ORF) II (p30 and p28, respectively) acts as a negative regulator of both Tax and Rex by binding to and retaining their mRNA in the nucleus, leading to reduced protein expression and virion production. Further characterization revealed that p28 was distinct from p30 in that it was devoid of major transcriptional modulating activity, suggesting potentially divergent functions that may be responsible for the distinct pathobiologies of HTLV-1 and HTLV-2. In this study, we investigated the functional significance of p28 in HTLV-2 infection, proliferation, and immortaliztion of primary T-cells in culture, and viral survival in an infectious rabbit animal model. An HTLV-2 p28 knockout virus (HTLV-2Deltap28) was generated and evaluated. Infectivity and immortalization capacity of HTLV-2Deltap28 in vitro was indistinguishable from wild type HTLV-2. In contrast, we showed that viral replication was severely attenuated in rabbits inoculated with HTLV-2Deltap28 and the mutant virus failed to establish persistent infection. We provide direct evidence that p28 is dispensable for viral replication and cellular immortalization of

  19. Neutralizing monoclonal antibodies against hepatitis C virus E2 protein bind discontinuous epitopes and inhibit infection at a postattachment step

    DEFF Research Database (Denmark)

    Sabo, Michelle C; Luca, Vincent C; Prentoe, Jannick

    2011-01-01

    The E2 glycoprotein of hepatitis C virus (HCV) mediates viral attachment and entry into target hepatocytes and elicits neutralizing antibodies in infected patients. To characterize the structural and functional basis of HCV neutralization, we generated a novel panel of 78 monoclonal antibodies (M...

  20. From hybridomas to a robust microalgal-based production platform: molecular design of a diatom secreting monoclonal antibodies directed against the Marburg virus nucleoprotein.

    Science.gov (United States)

    Hempel, Franziska; Maurer, Michael; Brockmann, Björn; Mayer, Christian; Biedenkopf, Nadine; Kelterbaum, Anne; Becker, Stephan; Maier, Uwe G

    2017-07-27

    The ideal protein expression system should provide recombinant proteins in high quality and quantity involving low production costs only. However, especially for complex therapeutic proteins like monoclonal antibodies many challenges remain to meet this goal and up to now production of monoclonal antibodies is very costly and delicate. Particularly, emerging disease outbreaks like Ebola virus in Western Africa in 2014-2016 make it necessary to reevaluate existing production platforms and develop robust and cheap alternatives that are easy to handle. In this study, we engineered the microalga Phaeodactylum tricornutum to produce monoclonal IgG antibodies against the nucleoprotein of Marburg virus, a close relative of Ebola virus causing severe hemorrhagic fever with high fatality rates in humans. Sequences for both chains of a mouse IgG antibody were retrieved from a murine hybridoma cell line and implemented in the microalgal system. Fully assembled antibodies were shown to be secreted by the alga and antibodies were proven to be functional in western blot, ELISA as well as IFA studies just like the original hybridoma produced IgG. Furthermore, synthetic variants with constant regions of a rabbit IgG and human IgG with optimized codon usage were produced and characterized. This study highlights the potential of microalgae as robust and low cost expression platform for monoclonal antibodies secreting IgG antibodies directly into the culture medium. Microalgae possess rapid growth rates, need basically only water, air and sunlight for cultivation and are very easy to handle.