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Sample records for virus hiv antigens

  1. Unpolarized release of vaccinia virus and HIV antigen by colchicine treatment enhances intranasal HIV antigen expression and mucosal humoral responses.

    Directory of Open Access Journals (Sweden)

    Yan Zhang

    Full Text Available The induction of a strong mucosal immune response is essential to building successful HIV vaccines. Highly attenuated recombinant HIV vaccinia virus can be administered mucosally, but even high doses of immunization have been found unable to induce strong mucosal antibody responses. In order to solve this problem, we studied the interactions of recombinant HIV vaccinia virus Tiantan strain (rVTT-gagpol in mucosal epithelial cells (specifically Caco-2 cell layers and in BALB/c mice. We evaluated the impact of this virus on HIV antigen delivery and specific immune responses. The results demonstrated that rVTT-gagpol was able to infect Caco-2 cell layers and both the nasal and lung epithelia in BALB/c mice. The progeny viruses and expressed p24 were released mainly from apical surfaces. In BALB/c mice, the infection was limited to the respiratory system and was not observed in the blood. This showed that polarized distribution limited antigen delivery into the whole body and thus limited immune response. To see if this could be improved upon, we stimulated unpolarized budding of the virus and HIV antigens by treating both Caco-2 cells and BALB/c mice with colchicine. We found that, in BALB/c mice, the degree of infection and antigen expression in the epithelia went up. As a result, specific immune responses increased correspondingly. Together, these data suggest that polarized budding limits antigen delivery and immune responses, but unpolarized distribution can increase antigen expression and delivery and thus enhance specific immune responses. This conclusion can be used to optimize mucosal HIV vaccine strategies.

  2. GB Virus Type C Envelope Protein E2 Elicits Antibodies That React with a Cellular Antigen on HIV-1 Particles and Neutralize Diverse HIV-1 Isolates

    Science.gov (United States)

    Mohr, Emma L.; Xiang, Jinhua; McLinden, James H.; Kaufman, Thomas M.; Chang, Qing; Montefiori, David C.; Klinzman, Donna; Stapleton, Jack T.

    2012-01-01

    Broadly neutralizing Abs to HIV-1 are well described; however, identification of Ags that elicit these Abs has proven difficult. Persistent infection with GB virus type C (GBV-C) is associated with prolonged survival in HIV-1–infected individuals, and among those without HIV-1 viremia, the presence of Ab to GBV-C glycoprotein E2 is also associated with survival. GBV-C E2 protein inhibits HIV-1 entry, and an antigenic peptide within E2 interferes with gp41-induced membrane perturbations in vitro, suggesting the possibility of structural mimicry between GBV-C E2 protein and HIV-1 particles. Naturally occurring human and experimentally induced GBV-C E2 Abs were examined for their ability to neutralize infectious HIV-1 particles and HIV-1–enveloped pseudovirus particles. All GBV-C E2 Abs neutralized diverse isolates of HIV-1 with the exception of rabbit anti-peptide Abs raised against a synthetic GBV-C E2 peptide. Rabbit anti–GBV-C E2 Abs neutralized HIV-1–pseudotyped retrovirus particles but not HIV-1–pseudotyped vesicular stomatitis virus particles, and E2 Abs immune-precipitated HIV-1 gag particles containing the vesicular stomatitis virus type G envelope, HIV-1 envelope, GBV-C envelope, or no viral envelope. The Abs did not neutralize or immune-precipitate mumps or yellow fever viruses. Rabbit GBV-C E2 Abs inhibited HIV attachment to cells but did not inhibit entry following attachment. Taken together, these data indicate that the GBV-C E2 protein has a structural motif that elicits Abs that cross-react with a cellular Ag present on retrovirus particles, independent of HIV-1 envelope glycoproteins. The data provide evidence that a heterologous viral protein can induce HIV-1–neutralizing Abs. PMID:20826757

  3. ARCHITECT® HIV Ag/Ab Combo assay: correlation of HIV-1 p24 antigen sensitivity and RNA viral load using genetically diverse virus isolates.

    Science.gov (United States)

    Brennan, Catherine A; Yamaguchi, Julie; Vallari, Ana; Swanson, Priscilla; Hackett, John R

    2013-06-01

    HIV antigen/antibody (Ag/Ab) combination assays represent a significant advancement in assays used for diagnosing HIV infection based on their ability to detect acute and chronic infections. During acute HIV infection (AHI), detection depends on assay sensitivity for p24 Ag. To directly compare the Ag sensitivity of the ARCHITECT(®) HIV Ag/Ab Combo assay to RNA viral load using cell culture supernatants of virus isolates. HIV-1 isolates allow correlation in the total absence of an antibody response to infection and across genetically diverse HIV-1 group M strains. Thirty-five HIV-1 isolates comprising subtypes A-D, F and G, CRF01_AE, CRF02_AG, and unique recombinant forms were evaluated. Cell-free culture supernatant for each isolate was diluted to four levels and tested in the HIV Combo assay to determine a signal to cutoff ratio and the RealTime(®) HIV-1 assay to quantify RNA. The RNA copies/mL at the HIV Combo assay cutoff was determined. The median RNA copies/mL at the HIV Combo assay cutoff was 57,900 for individual virus isolates (range 26,440-102,400). A single plot of all the data gave a value of 58,500RNA copies/mL. An analysis of data published for acute HIV infection in human subjects gave a similar result; HIV Combo detected 97% of AHIs with RNA copies/mL > 30,700. Based on analysis of virus isolates, the ARCHITECT HIV Combo assay can detect p24 Ag when RNA is above approximately 58,000copies/mL. The correlation of viral load and Ag sensitivity was consistent across genetically diverse HIV-1 group M strains. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Assessment of the ability of a fourth-generation immunoassay for human immunodeficiency virus (HIV) antibody and p24 antigen to detect both acute and recent HIV infections in a high-risk setting.

    Science.gov (United States)

    Pandori, Mark W; Hackett, John; Louie, Brian; Vallari, Ana; Dowling, Teri; Liska, Sally; Klausner, Jeffrey D

    2009-08-01

    An immunoassay (IA) that simultaneously detects both antibody to human immunodeficiency virus (HIV) and HIV p24 antigen (Architect HIV Ag/Ab Combo) was evaluated for its ability to detect HIV infection by using a panel of specimens collected from individuals recently infected with HIV type 1 (HIV-1). This IA was found to be capable of detecting the majority (89%) of infections, including 80% of those considered acute infections based on the presence of HIV RNA and the lack of detectable antibody to HIV. Substantial improvements in detection of recent infections by the Architect HIV Ag/Ab Combo relative to previous generations of IAs as well as the capacity to detect acute infections have important implications for HIV prevention strategies.

  5. Prevalence, risk factors, and impact of isolated antibody to hepatitis B core antigen and occult hepatitis B virus infection in HIV-1-infected pregnant women.

    Science.gov (United States)

    Khamduang, Woottichai; Ngo-Giang-Huong, Nicole; Gaudy-Graffin, Catherine; Jourdain, Gonzague; Suwankornsakul, Weerapong; Jarupanich, Tapnarong; Chalermpolprapa, Veeradate; Nanta, Sirisak; Puarattana-Aroonkorn, Noossara; Tonmat, Sakchai; Lallemant, Marc; Goudeau, Alain; Sirirungsi, Wasna

    2013-06-01

    Prevalence and risk factors for isolated antibody to hepatitis B core antigen (anti-HBc) and occult hepatitis B virus (HBV) infection are not well known in human immunodeficiency virus type 1 (HIV-1)-infected pregnant women. It is unclear if women with occult infections are at risk of transmitting HBV to their infants. HIV-1-infected and HBV surface antigen (HBsAg)-negative pregnant women were tested for antibody to HBsAg (anti-HBs) and anti-HBc using enzyme immunoassay. Women with isolated anti-HBc were assessed for occult HBV infection, defined as HBV DNA levels >15 IU/mL, using the Abbott RealTime HBV DNA assay. Infants born to women with isolated anti-HBc and detectable HBV DNA were tested at 4 months of age for HBV DNA. Logistic regression analysis was used to identify factors associated with isolated anti-HBc and occult HBV infection. Among 1812 HIV-infected pregnant women, 1682 were HBsAg negative. Fourteen percent (95% confidence interval [CI], 12%-15%) of HBsAg-negative women had an isolated anti-HBc that was independently associated with low CD4 count, age >35 years, birth in northern Thailand, and positive anti-hepatitis C virus serology. Occult HBV infection was identified in 24% (95% CI, 18%-30%) of women with isolated anti-HBc, representing 2.6% (95% CI, 1.9%-3.5%) of HIV-1-infected pregnant women, and was inversely associated with HIV RNA levels. None of the women with isolated anti-HBc and occult HBV infection transmitted HBV to their infants. HIV-1-infected pregnant women with isolated anti-HBc and occult HBV infection have very low HBV DNA levels and are thus at very low risk to transmit HBV to their infants.

  6. Hepatitis B virus surface antigen and anti-hepatitis C virus rapid tests underestimate hepatitis prevalence among HIV-infected patients

    DEFF Research Database (Denmark)

    Hønge, Bl; Jespersen, S; Medina, C

    2014-01-01

    OBJECTIVES: In the case of coinfection with HIV and hepatitis B virus (HBV) and/or hepatitis C virus (HCV), hepatic disease progression is often accelerated, with higher rates of liver cirrhosis and liver-related mortality. We aimed to evaluate the performance of the rapid tests used routinely...

  7. Evaluation of three enzyme immunoassays for HIV-1 antigen detection.

    Science.gov (United States)

    Willoughby, P B; Lisker, A; Folds, J D

    1989-01-01

    Three enzyme immunoassay (EIA) methods for the detection of human immunodeficiency virus (HIV-1) were evaluated. Serum or plasma samples from 22 individuals seropositive for HIV-1 antibodies were tested with the Abbott, Coulter, and DuPont kits for presence of HIV-1 p24 antigen. Another 12 samples were tested with two kits only. Discordant results were obtained with 9 of 34 (26%) HIV-1-antibody-positive patient samples tested. Most of these discrepancies were found in samples containing less than 30 pg/ml of HIV-1 p24 core antigen. A sampling of sera from normal blood donors and patients with infectious or autoimmune diseases revealed a low level of false positive reactions, especially with sera containing antinuclear antibodies or rheumatoid factor. Noteworthy is the frequency of false positive reactions seen with the DuPont EIA for HIV-1 p24 antigen. 18/111 sera (16.2%) containing auto-antibodies tested positively with the DuPont HIV-1 p24 antigen EIA. The nonspecific nature of the test reactivity for 9/10 of these samples was confirmed using an HIV-1 p24 antigen inhibition assay. These findings are discussed in light of the need for HIV-1 antigen detection in the clinical laboratory and of other methods for HIV-1 detection: the polymerase chain reaction and measurements of reverse transcriptase activity.

  8. Correlation of serum HIV antigen and antibody with clinical status in HIV-infected patients.

    Science.gov (United States)

    Paul, D A; Falk, L A; Kessler, H A; Chase, R M; Blaauw, B; Chudwin, D S; Landay, A L

    1987-08-01

    An enzyme immunoassay (EIA) has been developed which detects antigen(s) (Ag) of the human immunodeficiency virus (HIV) in the serum of patients with the acquired immunodeficiency syndrome (AIDS), AIDS-related complex (ARC), and patients at high risk for HIV infection. The test has a sensitivity of approximately 50 pg/ml of HIV protein. The specificity of the assay was determined with various virus infected cell lines, normal human sera/plasma, and serum from patients not known to be at risk for HIV infection. No false-positive HIV-Ag results were seen. Sera from 69% of patients with AIDS were positive for HIV-Ag as were 46% of patients with ARC and 19% of asymptomatic, HIV-antibody-positive individuals. There were significant associations between the stage of HIV infection--ie, AIDS vs ARC vs asymptomatic--and the detection of HIV-Ag in serum (p less than 0.0001) and the lack of detection of antibody to HIV core Ag (p less than 0.0001). HIV-Ag was also found in the serum of two asymptomatic antibody-negative individuals who were at high risk for AIDS and who later developed HIV antibody. The presence of HIV-Ag in sera was confirmed by an inhibition procedure. Thus, HIV-Ag can be detected in the serum of infected individuals prior to antibody production and correlates with the clinical stage of HIV infection.

  9. [Value of enzyme-linked immunosorbent assay for detection of p24 antigen of human immunodeficiency virus in confirmation of HIV-infection].

    Science.gov (United States)

    Ruzaeva, L A; Ol'khovskiĭ, I A; Neshumaev, D A; Shevchenko, N M; Vinogradova, M N

    2008-01-01

    To evaluate diagnostic value of p24 antigen detection for algorithm of confirmatory diagnostics of HIV-infection. Concurrently with Western blot assay (WB, "New Lav Blot1", Bio-Rad), tests for detection of p24 antigen of HIV (Genetic Systems HIV-1 Ag EIA", "VectoHIV-1 p24-antigen confirming test", and "DS-EIA-HIV-AG-SCREEN") were used for confirmation of first-positive result of immuno-enzyme assay. p24 HIV antigen was detected in serum samples in 8.4% of patients with equivocal result of WB and in 4.2% of patients with negative and positive results of WB. Presence of p24 was correlated with high viral load, and, in patients with confirmed diagnosis, with low CD4 cells count (testing. In groups of persons with negative and equivocal results of WB assay, detection of HIV p24 antigen points to the presence of infection and could be the reason for the final diagnosis. Detection of p24 in patients with positive result of WB assay allows to consider them as probable candidates for highly active antiretroviral therapy.

  10. Acute HIV-1 Infection in Antigen/Antibody-negative Blood Donors in ...

    African Journals Online (AJOL)

    Acute HIV-1 Infection in Antigen/Antibody-negative Blood Donors in Dar es Salaam, Tanzania. ... Fourth generation human immunodeficiency virus (HIV) antigen (Ag)/antibody (Ab) enzyme-linked immunosorbent assay (ELISA) test used in the current screening of blood donors at the National Blood Transfusion Service ...

  11. [Evaluation of Abbott Fourth Generation HIV Antigen and Antibody Assays.].

    Science.gov (United States)

    Kang, Hee Jung; Yoo, Kyeong Ha; Kim, Han Sung; Cho, Hyoun Chan

    2006-02-01

    In order to reduce the diagnostic window period between the time of human immunodeficiency virus (HIV) infection and serological diagnosis, new fourth generation screening assays which detect HIV p24 antigen and specific antibody simultaneously have been developed. In this study, we evaluated the performance of a new fourth generation assay. We compared a new fourth generation assay, Architect HIV Ag/Ab combo, with another fourth generation assay AxSYM HIV Ag/Ab combo and a third generation assay, AxSYM HIV 1/2 gO for their performance. The assays were evaluated using 3 HIV seroconversion panels, 305 sera of healthy subjects and 100 sera of patients with HBsAg or anti-HCV antibodies. Within-run and total coefficient variations of the three screening assays were analyzed for the evaluation of precision. Architect HIV Ag/Ab combo shortened the window period by 8.7+/-2.1 days relative to AxSYM HIV 1/2 gO and 2.0+/-2.0 days relative to AxSYM HIV Ag/Ab combo in seroconversion panels. Architect HIV Ag/Ab combo presented the best performance in precision among the three reagents; total CV for positive control was 3.6%, 9.6% and 4.6% for Architect HIV Ag/Ab combo, AxSYM HIV Ag/Ab combo and AxSYM HIV 1/2 gO, respectively. Specificities of three assays were not different in this study. HIV Ag/Ab combined assays reduced the diagnostic window as compared to the third generation screening assays, enabling an earlier diagnosis of HIV infection. A new fourth generation assay, Architect HIV Ag/Ab combo presents a better performance than AxSYM HIV Ag/Ab combo, showing improved seroconversion sensitivity and precision.

  12. Circulation of HIV antigen in blood according to stage of infection, risk group, age and geographic origin

    NARCIS (Netherlands)

    Goudsmit, J.; Paul, D. A.

    1987-01-01

    Human immunodeficiency virus antigen (HIV-ag) was determined by enzyme immunoassay (EIA) in HIV-antibody (anti-HIV) positive as well as pre-anti-HIV seroconversion sera and the results analysed according to stage of infection, risk group, age and geographic origin. Eleven (19%) of 58 homosexual men

  13. Impact of highly active antiretroviral therapy (HAART) on the natural history of hepatitis B virus (HBV) and HIV coinfection: relationship between prolonged efficacy of HAART and HBV surface and early antigen seroconversion.

    Science.gov (United States)

    Miailhes, Patrick; Trabaud, Mary-Anne; Pradat, Pierre; Lebouché, Bertrand; Chevallier, Michèle; Chevallier, Philippe; Zoulim, Fabien; Trepo, Christian

    2007-09-01

    Coinfection with hepatitis B virus (HBV) in human immunodeficiency virus (HIV)-infected patients is common. However, little is known about the natural history of chronic hepatitis B in HIV-infected populations, especially the impact of highly active antiretroviral therapy (HAART) on the outcome of HBV early antigen (HBeAg) and HBV surface antigen (HBsAg) status. The characteristics of 92 patients coinfected with HIV and HBV were retrospectively assessed before and after HAART and lamivudine treatment to determine the impact of treatment on chronic hepatitis B and factors associated with HBeAg and/or HBsAg seroconversion. During follow-up, 82 patients received antiretroviral therapy, 79 of whom received HAART. Twenty-eight of the 76 patients who were administered lamivudine therapy developed lamivudine resistance mutations. While receiving antiretroviral therapy, 10 of 59 HBeAg-positive patients developed antibody to HBeAg, 3 of 10 cleared HBsAg, and 2 of 3 developed antibody to HBsAg. Two of 23 HBeAg-negative patients cleared HBsAg and developed antibody to HBsAg. HBeAg and/or HBsAg seroconversion combined with an undetectable HBV DNA level (i.e., an HBV response) correlated with a sustained HIV response (P=.001), shorter duration of antiretroviral therapy (P=.058), and more-severe disease, as evaluated by Centers for Disease Control and Prevention staging (for stage B vs. stage A, P=.029; for stage C vs. stage A, P=.069). For patients with elevated baseline alanine aminotransferase levels, the HBV response correlated significantly with a greater increase in CD4 cell count while receiving HAART. In HIV-HBV-coinfected patients, HBV response correlated with a sustained HIV response to antiretroviral therapy, usually HAART including lamivudine.

  14. Engineering HIV-Specific Immunity with Chimeric Antigen Receptors.

    Science.gov (United States)

    Kitchen, Scott G; Zack, Jerome A

    2016-12-01

    HIV remains a highly important public health and clinical issue despite many recent advances in attempting to develop a cure, which has remained elusive for most people infected with HIV. HIV disease can be controlled with pharmacologic therapies; however, these treatments are expensive, may have severe side effects, and are not curative. Consequently, an improved means to control or eliminate HIV replication is needed. Cytotoxic T lymphocytes (CTLs) play a critical role in controlling viral replication and are an important part in the ability of the immune response to eradicate most viral infections. There are considerable efforts to enhance CTL responses in HIV-infected individuals in hopes of providing the immune response with armaments to more effectively control viral replication. In this review, we discuss some of these efforts and focus on the development of a gene therapy-based approach to engineer hematopoietic stem cells with an HIV-1-specific chimeric antigen receptor, which seeks to provide an inexhaustible source of HIV-1-specific immune cells that are MHC unrestricted and superior to natural antiviral T cell responses. These efforts provide the basis for further development of T cell functional enhancement to target and treat chronic HIV infection in hopes of eradicating the virus from the body.

  15. Evaluation of the siemens HIV antigen-antibody immunoassay.

    Science.gov (United States)

    Vallefuoco, Luca; Aden Abdi, Fatima; Sorrentino, Rosanna; Spalletti-Cernia, Daniela; Mazzarella, Claudia; Barbato, Sara; Perna, Enzo; Buffolano, Wilma; Di Nicuolo, Giuseppe; Portella, Giuseppe

    2014-01-01

    Fourth-generation assays for the simultaneous detection of human immunodeficiency virus (HIV) antigen and antibodies are available on the international market and are currently used for blood donor screening and for HIV diagnosis. In this study we evaluated the performance of the novel automated fourth-generation ADVIA Centaur® HIV Ag/Ab Combo assay. The assay detected seroconversion at the same bleed or at least one bleed earlier in panels with respect to other assays and showed a detection efficacy equal to those of other assays in a low-titer panel. Samples obtained from blood donors (n = 2,778) or from HIV-positive patients (HIV-1 B subtype, n = 82; non-B subtype, n = 71) were also tested, showing a good correlation with other fourth-generation assays. We assessed the performance of 3 fourth-generation assays for detecting in utero transmitted anti-HIV antibodies and found a more specific detection efficiency with the ADVIA Centaur HIV Ag/Ab Combo assay compared to the other fourth-generation assays.

  16. Hepatitis B, C and Human Immunodeficiency Virus (HIV) Co ...

    African Journals Online (AJOL)

    Background: Nigeria which has one of the world's highest burden of children living with Sickle cell anaemia is also endemic for hepatitis B, C and the Human immunodeficiency virus (HIV). This study set out to determine the prevalence of Hepatitis B surface antigen (HBsAg), antibodies to Hepatitis C Virus (HCV) and Human ...

  17. Antigenic drift of viruses within a host: a finite site model with demographic stochasticity.

    Science.gov (United States)

    Sasaki, A; Haraguchi, Y

    2000-09-01

    We theoretically study the antigenic drift of viruses within an infected host, as observed in human immunodeficiency virus (HIV) and equine infectious anemia virus (EIAV) infections, assuming that a finite number of antigen-determining sites at the viral envelop gene are responsible for the specific immune response. The pattern of antigen evolution becomes more complex than that predicted from the previous one-dimensional antigen space models. If the viral growth rate is sufficiently large, the demographic stochasticity for the fate of a new antigen mutant can be neglected. The high dimensionality in the way a virus escapes the immune defense in genotype space could then causes a rapid increase in the antigenic diversity and the total viral density, until finally the whole antigen genotypes are used up. The viral population is then driven to extinction in a host by the enhanced immune response to all genotypes. In contrast, if the viral growth rate is moderate or small so that only a small fraction of new antigen mutants can survive during the initial endangered period of random extinction, the viral antigenic diversity and the total density remain bounded, thereby enabling them to persist for a prolonged period by shifting the dominant antigen types. The phylogenetic pattern of antigen divergence is well characterized by the mean number of surviving antigen mutants from an antigen genotype. The substitution rate at antigen-determining sites increases as the efficiency of host immune response increases.

  18. Engineering HIV-Resistant, Anti-HIV Chimeric Antigen Receptor T Cells.

    Science.gov (United States)

    Hale, Malika; Mesojednik, Taylor; Romano Ibarra, Guillermo S; Sahni, Jaya; Bernard, Alison; Sommer, Karen; Scharenberg, Andrew M; Rawlings, David J; Wagner, Thor A

    2017-03-01

    The treatment or cure of HIV infection by cell and gene therapy has been a goal for decades. Recent advances in both gene editing and chimeric antigen receptor (CAR) technology have created new therapeutic possibilities for a variety of diseases. Broadly neutralizing monoclonal antibodies (bNAbs) with specificity for the HIV envelope glycoprotein provide a promising means of targeting HIV-infected cells. Here we show that primary human T cells engineered to express anti-HIV CARs based on bNAbs (HIVCAR) show specific activation and killing of HIV-infected versus uninfected cells in the absence of HIV replication. We also show that homology-directed recombination of the HIVCAR gene expression cassette into the CCR5 locus enhances suppression of replicating virus compared with HIVCAR expression alone. This work demonstrates that HIV immunotherapy utilizing potent bNAb-based single-chain variable fragments fused to second-generation CAR signaling domains, delivered directly into the CCR5 locus of T cells by homology-directed gene editing, is feasible and effective. This strategy has the potential to target HIV-infected cells in HIV-infected individuals, which might help in the effort to cure HIV. Copyright © 2017 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.

  19. Evaluation of performance of human immunodeficiency virus antigen/antibody combination assays in Taiwan.

    Science.gov (United States)

    Chang, Chun-Kai; Kao, Cheng-Feng; Lin, Pi-Han; Huang, Hui-Lin; Ho, Shu-Yuan; Wong, Kuo-Chen; Lin, Bo-Chang; Yeh, Chang-Ching; Lee, Chia-Yeh; Kao, Chuan-Liang; Lee, Chun-Nan; Chang, Sui-Yuan; Yang, Jyh-Yuan

    2017-08-01

    The fourth-generation human immunodeficiency virus (HIV) combination assay, which can simultaneously detect the presence of anti-HIV antibody and HIV antigen, has been shown to shorten the window period in HIV diagnosis compared with the third-generation HIV antibody immunoassay. This study was aimed to determine the performance of HIV combination assays in Taiwan, where the HIV-1 seroprevalence is 0.007% and HIV-2 infection has never been reported. Performance of three fourth-generation HIV Ag/Ab combination assays (Dia.Pro, Wantai, and Bio-Rad) and one third-generation HIV Ab immunoassay (AxSYM HIV 1/2 gO) was assessed. A total of 152 specimens, including 86 confirmed HIV-seropositive and 66 HIV-seronegative samples, were used in the study. The sensitivity of four assays varied from 98.8% to 100%, and specificity varied from 98.5% to 100%. Performance of the 75 equivocal samples, the HIV status of which was confirmed later, in terms of negative prediction varied from 81.8% to 87.5%. The Bio-Rad and Dia.Pro assays exhibited higher sensitivity for the detection of p24 antigen among the three fourth-generation HIV combination assays. The three fourth-generation HIV Ag/Ab combination assays exhibited better sensitivity, specificity, and negative prediction than the third-generation HIV Ab immunoassay. Copyright © 2015. Published by Elsevier B.V.

  20. Multicenter evaluation of a new rapid automated human immunodeficiency virus antigen detection assay.

    Science.gov (United States)

    Weber, B; Mühlbacher, A; Michl, U; Paggi, G; Bossi, V; Sargento, C; Camacho, R; Fall, E H; Berger, A; Schmitt, U; Melchior, W

    1999-03-01

    Although human immunodeficiency virus (HIV) antigen assays are of limited value for monitoring antiretroviral therapy, they play an important role for confirmatory testing of fourth generation HIV screening enzyme immunoassay (EIA) reactive samples. In a multicenter study, a new automated rapid p24 antigen assay, Elecsys HIV Ag (Roche Diagnostics Boehringer Mannheim GmbH, Penzberg, Germany), was compared to FDA licensed tests (Abbott HIV-1 Ag monoclonal and Coulter HIV-1 p24 antigen assay). In the evaluation 27 seroconversion panels were included, sera from the acute phase of infection, single and follow-up samples from HIV antibody positive patients, dilution series of HIV antigen positive standards, sera and cell culture supernatants infected with different HIV-1 subtypes (A-H, and O) HIV-2 and recombinant HIV-1 (gag/env) isolates. To challenge the specificity of the new assay, 2565 unselected blood donors, sera from pregnant women, dialysis and hospitalized patients and 407 potentially cross-reactive samples were investigated. Acute HIV infection was detected in three to eight seroconversion panels earlier with Elecsys HIV Ag than with the alternative assays. Higher numbers of serum samples from HIV infected patients tested positive by Elecsys HIV Ag than with the comparative assays. All HIV-1 subtypes and HIV-2 isolates were recognized with Elecsys HIV Ag. Abbott HIV-1 Ag monoclonal and Coulter HIV-1 p24 antigen assay showed a variable sensitivity for the different HIV-1 subtypes. The specificity of Elecsys HIV Ag and Coulter HIV-1 p24 antigen assay were 99.8 and 99.93%, respectively. All the eight sera that were false reactive by Elecsys HIV Ag were tested negative with the Elecsys HIV Ag Neutralization Test. In conclusion, Elecsys HIV Ag was more sensitive than the alternative assays and showed a high specificity in combination with the neutralization assay. The very short incubation time of 18 min and the fully automated procedure of Elecsys HIV Ag which

  1. Comparison between Elecsys HBsAg II and architect HBsAg QT assays for quantification of hepatitis B surface antigen among patients coinfected with HIV and hepatitis B virus.

    Science.gov (United States)

    Maylin, Sarah; Boyd, Anders; Delaugerre, Constance; Zoulim, Fabien; Lavocat, Fabien; Simon, François; Girard, Pierre-Marie; Lacombe, Karine

    2012-02-01

    Hepatitis B surface antigen (HBsAg) quantification has been steadily gaining interest as a clinical marker of therapeutic efficacy, for which two commercial assays are currently available: Architect HBsAg QT (Architect) and Elecsys HBsAg II (Elecsys). HBsAg quantification was evaluated using both assays in 126 human immunodeficiency virus (HIV) and hepatitis B virus (HBV)-coinfected patients initiating treatment with tenofovir dipivoxil fumarate. Linear regression and correlation were used to establish the relationship between the two methods. Bland-Altman analysis was performed to determine mean between-assay difference and limits of agreement (LOA) (±2 standard deviations [SD]) both overall and stratified on HBV (hepatitis B envelope antigen [HBeAg] status, replication, genotype, HBV mutants) or HIV (CD4(+) cell count) cofactors. There was a significant correlation between Elecsys and Architect assays (correlation coefficient, r = 0.959; P Architect, which was consistent across levels of CD4(+) cell count, presence of precore and YMDD mutations, and HBeAg status. A slightly larger mean between-assay difference was observed with genotypes A and G (0.196 and 0.201, respectively) versus HBV genotypes D and E (0.036 and 0.030, respectively). Mutations on the S region at position s120/s145 were the only determinant in which the mean between-assay difference in HBsAg quantification was lower than the null value (-0.078). In conclusion, the Elecsys assay, with automatic on-board dilution, is capable of quantifying serum HBsAg levels in HIV-HBV-coinfected patients, with very high correlation with the Architect assay.

  2. Detection of HIV-1 antigen based on magnetic tunnel junction sensor and magnetic nanoparticles

    CERN Document Server

    Li, L; Zhou, Y; Pong, P W T

    2016-01-01

    In recent years, it is evidenced that the individuals newly infected HIV are transmitting the virus prior to knowing their HIV status. Identifying individuals that are early in infection with HIV antibody negative (window period) remains problematic. In the newly infected individuals, HIV antigen p24 is usually present in their serum or plasma 7-10 days before the HIV antibody. After antibody production initiates, the p24 antigen is bound into immune complexes. That means the detectable p24 antigens in serum/plasma are short-lived, and their amount is in the pg/ml range. Thus, a rapid quantitative bio-detection system with high-sensitivity is required to achieve early disease diagnosis. Magnetoresistive (MR) biosensor with ultra-high sensitivity possesses great potential in this area. In this study, a p24 detection assay using MgO-based magnetic tunnel junction (MTJ) sensor and 20-nm magnetic nanoparticles is reported.

  3. of human immunodeficiency virus (HIV)

    African Journals Online (AJOL)

    Context: With increasing feminization of the human immunodeficiency virus (HIV) pandemic especially in Africa, more seropositive women are getting pregnant. There is therefore an increasing need for prevention of mother to child transmission (PMTCT) of HIV and increased need for awareness by our women. Objective: ...

  4. Reduction of the diagnostic window with a new combined p24 antigen and human immunodeficiency virus antibody screening assay.

    Science.gov (United States)

    Gürtler, L; Mühlbacher, A; Michl, U; Hofmann, H; Paggi, G G; Bossi, V; Thorstensson, R; G-Villaescusa, R; Eiras, A; Hernandez, J M; Melchior, W; Donie, F; Weber, B

    1998-11-01

    In order to reduce the window phase between time of human immunodeficiency virus (HIV) infection and laboratory diagnosis, new fourth generation screening assays which permit a simultaneous detection of HIV antigen and antibody have been developed. In a multicenter study, a new automated fourth generation assay, Enzymun-Test HIV Combi (Boehringer Mannheim GmbH) was compared to third generation assay, p24 antigen tests and Western blot. A total of 37 seroconversion panels, samples of the early infection (n = 42), HIV-1 antibody positive sera, including subtypes A E, and O (n = 1118), HIV-2 positive samples (n = 252) and cell culture supernatants infected with different HIV-1 subtypes and HIV-2 (n = 50), blood donors (n = 6649), hospitalized patients (n = 475), HIV neg. sera with indeterminate Western blot (n = 32), potentially cross reactive serum samples (n = 435) and HIV negative specimens from Cameroon (n = 68) were tested. A total of 16 of 29 seroconversions were detected on average 8.5 days earlier with Enzymun-Test HIV Combi than HIV-1/HIV-2 3rd generation EIA (Abbott Laboratories). Overall, in the 29 panels investigated comparatively with the two assays, the mean time delay between Enzymun-Test HIV Combi and HIV-1/HIV-2 3rd generation EIA was 4.7 days. HIV antigen was detected in three out of 35 seroconversions one bleed earlier with HIV-1 Ag Monoclonal than with Enzymun-Test HIV Combi. Enzymun-Test HIV Combi showed a sensitivity of 100% for HIV antibody detection for HIV-1 group M and O and HIV-2 positive specimens. While p24 antigen of different HIV-1 subtypes was detected with Enzymun-Test HIV Combi in all the 49 cell culture supernatants, HIV Ag was not detected in an HIV-2 virus lysate. A total of 66 false positive results out of 7659 HIV negative samples were obtained with the Enzymun-Test HIV Combi. The specificity for unselected blood donors was 99.6%. The Enzymun-Test HIV Combi permits an earlier diagnosis of HIV infection than third generation

  5. Global analysis of a class of HIV models with immune response and antigenic variation

    CERN Document Server

    Souza, Max O

    2008-01-01

    We study the global stability of two models for the HIV virus dynamics, that take into account the CTL immune response and antigenic variation. We show that both models are globally asymptotically stable, by using appropriate Lyapunov functions. For both models, we characterise the stable equilibrium points for the entire biologically relevant parameter range. In the model with antigenic variation, which can have a large number of equilibrium points, this allows us to determine what is the diversity of the persistent strains.

  6. Screening for Human Immunodeficiency Virus (HIV)

    Science.gov (United States)

    Understanding Task Force Recommendations Screening for Human Immunodeficiency Virus (HIV) The U.S. Preventive Services Task Force (Task Force) has issued a final recommendation statement on Screening for Human Immunodeficiency Virus (HIV) . This ...

  7. Human immunodeficiency virus (HIV) seropositivity and hepatitis B ...

    African Journals Online (AJOL)

    Method: A total of 130 donors comprising 120 commercial donors and 10 voluntary donors were tested for antibodies to human immunodeficiency virus and hepatitis B surface antigen in Benin city using Immunocomb HIV - 1 and 2 Biospot kit and Quimica Clinica Aplicada direct latex agglutination method respectively.

  8. Inhibition of human immunodeficiency virus type 1 (HIV-1) penetration into target cells by synthetic peptides mimicking the N-terminus of the HIV-1 transmembrane glycoprotein

    NARCIS (Netherlands)

    Slepushkin, V. A.; Kornilaeva, G. V.; Andreev, S. M.; Sidorova, M. V.; Petrukhina, A. O.; Matsevich, G. R.; Raduk, S. V.; Grigoriev, V. B.; Makarova, T. V.; Lukashov, V. V.

    1993-01-01

    To investigate the mechanism of action of the 22-amino-acid HIV fusion peptide on HIV infection, we studied its influence on virus adsorption and HIV-induced syncytium formation. The effect of the peptide preparations on the synthesis of viral antigens in HIV-infected cell cultures was determined by

  9. Multicenter Evaluation of a New Automated Fourth-Generation Human Immunodeficiency Virus Screening Assay with a Sensitive Antigen Detection Module and High Specificity

    OpenAIRE

    Weber, Bernard; Gürtler, Lutz; Thorstensson, Rigmor; Michl, Ulrike; Mühlbacher, Annelies; Bürgisser, Philippe; Villaescusa, Roberto; Eiras, Adolfo; Gabriel, Christian; Stekel, Herbert; Tanprasert, Srivilai; Oota, Sinenaart; Silvestre, Maria-Jose; Marques, Cristina; Ladeira, Maria

    2002-01-01

    Fourth-generation assays for the simultaneous detection of human immunodeficiency virus (HIV) antigen and antibody that were available on the international market until now have antigen detection modules with relatively poor sensitivity and produce a higher rate of false-positive results than third-generation enzyme immunoassays (EIAs). The new Cobas Core HIV Combi EIA with an improved sensitivity for HIV p24 antigen was compared to alternative fourth- and third-generation assays, the p24 ant...

  10. 75 FR 22814 - Guidance for Industry: Nucleic Acid Testing (NAT) for Human Immunodeficiency Virus Type 1 (HIV-1...

    Science.gov (United States)

    2010-04-30

    ... Immunodeficiency Virus Type 1 (HIV-1) Nucleic Acid Test (NAT) and Hepatitis C Virus (HCV) NAT, on testing... test results, HIV-1 p24 antigen test results, and anti-HCV test results that were provided in the FDA... (Anti-HCV),'' August 5, 1993; ``Recommendations for Donor Screening with a Licensed Test for HIV-1...

  11. Antigenic analysis of some Nigerian street rabies virus using ...

    African Journals Online (AJOL)

    The authors studied 12 street rabies virus isolates from 3 states of Nigeria using both the anti-nucleocapsid and anti-glycoprotein monoclonal antibodies and cross-protection tests. It was observed that all the viruses were rabies having divergent antigenic presentation. Also noticed was an antigenic shift when the viruses ...

  12. Dengue viruses cluster antigenically but not as discrete serotypes

    NARCIS (Netherlands)

    L. Katzelnick (Leah); J.M. Fonville (Judith); G.D. Gromowski (Gregory D.); J.B. Arriaga (Jose Bustos); A. Green (Angela); S.L. James (Sarah ); L. Lau (Louis); M. Montoya (Magelda); C. Wang (Chunling); L.A. Van Blargan (Laura A.); C.A. Russell (Colin); H.M. Thu (Hlaing Myat); T.C. Pierson (Theodore C.); P. Buchy (Philippe); J.G. Aaskov (John G.); J.L. Muñoz-Jordán (Jorge L.); N. Vasilakis (Nikos); R.V. Gibbons (Robert V.); R.B. Tesh (Robert B.); A.D.M.E. Osterhaus (Albert); R.A.M. Fouchier (Ron); A. Durbin (Anna); C.P. Simmons (Cameron P.); E.C. Holmes (Edward C.); E. Harris (Eva); S.S. Whitehead (Stephen S.); D.J. Smith (Derek James)

    2015-01-01

    textabstractThe four genetically divergent dengue virus (DENV) types are traditionally classified as serotypes. Antigenic and genetic differences among the DENV types influence disease outcome, vaccine-induced protection, epidemic magnitude, and viral evolution.We scharacterized antigenic diversity

  13. Fusion of Epstein-Barr virus nuclear antigen-1-derived glycine-alanine repeat to trans-dominant HIV-1 Gag increases inhibitory activities and survival of transduced cells in vivo.

    Science.gov (United States)

    Hammer, Diana; Wild, Jens; Ludwig, Christine; Asbach, Benedikt; Notka, Frank; Wagner, Ralf

    2008-06-01

    Trans-dominant human immunodeficiency virus type 1 (HIV-1) Gag derivatives have been shown to efficiently inhibit late steps of HIV-1 replication in vitro by interfering with Gag precursor assembly, thus ranking among the interesting candidates for gene therapy approaches. However, efficient antiviral activities of corresponding transgenes are likely to be counteracted in particular by cell-mediated host immune responses toward the transgene-expressing cells. To decrease this potential immunogenicity, a 24-amino acid Gly-Ala (GA) stretch derived from Epstein-Barr virus nuclear antigen-1 (EBNA1) and known to overcome proteasomal degradation was fused to a trans-dominant Gag variant (sgD1). To determine the capacity of this fusion polypeptide to repress viral replication, PM-1 cells were transduced with sgD1 and GAsgD1 transgenes, using retroviral gene transfer. Challenge of stably transfected permissive cell lines with various viral strains indicated that N-terminal GA fusion even enhanced the inhibitory properties of sgD1. Further studies revealed that the GA stretch increased protein stability by blocking proteasomal degradation of Gag proteins. Immunization of BALB/c mice with a DNA vaccine vector expressing sgD1 induced substantial Gag-specific immune responses that were, however, clearly diminished in the presence of GA. Furthermore, recognition of cells expressing the GA-fused transgene by CD8(+) T cells was drastically reduced, both in vitro and in vivo, resulting in prolonged survival of the transduced cells in recipient mice.

  14. The global antigenic diversity of swine influenza A viruses

    DEFF Research Database (Denmark)

    Lewis, Nicola S; Russell, Colin A; Langat, Pinky

    2016-01-01

    Swine influenza presents a substantial disease burden for pig populations worldwide and poses a potential pandemic threat to humans. There is considerable diversity in both H1 and H3 influenza viruses circulating in swine due to the frequent introductions of viruses from humans and birds coupled...... with geographic segregation of global swine populations. Much of this diversity is characterized genetically but the antigenic diversity of these viruses is poorly understood. Critically, the antigenic diversity shapes the risk profile of swine influenza viruses in terms of their epizootic and pandemic potential....... Here, using the most comprehensive set of swine influenza virus antigenic data compiled to date, we quantify the antigenic diversity of swine influenza viruses on a multi-continental scale. The substantial antigenic diversity of recently circulating viruses in different parts of the world adds...

  15. Inexpensive designer antigen for anti-HIV antibody detection with high sensitivity and specificity.

    Science.gov (United States)

    Talha, Sheikh M; Salminen, Teppo; Chugh, Deepti A; Swaminathan, Sathyamangalam; Soukka, Tero; Pettersson, Kim; Khanna, Navin

    2010-03-01

    A novel recombinant multiepitope protein (MEP) has been designed that consists of four linear, immunodominant, and phylogenetically conserved epitopes, taken from human immunodeficiency virus (HIV)-encoded antigens that are used in many third-generation immunoassay kits. This HIV-MEP has been evaluated for its diagnostic potential in the detection of anti-HIV antibodies in human sera. A synthetic MEP gene encoding these epitopes, joined by flexible peptide linkers in a single open reading frame, was designed and overexpressed in Escherichia coli. The recombinant HIV-MEP was purified using a single affinity step, yielding >20 mg pure protein/liter culture, and used as the coating antigen in an in-house immunoassay. Bound anti-HIV antibodies were detected by highly sensitive time-resolved fluorometry, using europium(III) chelate-labeled anti-human antibody. The sensitivity and specificity of the HIV-MEP were evaluated using Boston Biomedica worldwide HIV performance, HIV seroconversion, and viral coinfection panels and were found to be comparable with those of commercially available anti-HIV enzyme immunoassay (EIA) kits. The careful choice of epitopes, high epitope density, and an E. coli-based expression system, coupled with a simple purification protocol and the use of europium(III) chelate-labeled tracer, provide the capability for the development of an inexpensive diagnostic test with high degrees of sensitivity and specificity.

  16. Prevalence of hepatitis b virus surface antigens (HBsag) and ...

    African Journals Online (AJOL)

    The prevalences of hepatitis B virus surface antigen (HBsAg) and hepatitis C virus (HCV) antibodies were determined in 560 blood donors sera using ELISA kits (DIALAB., Austria). Forty eight (8.57%) of these were positive for hepatitis B virus infection, while 33(5.89%) were positive to hepatitis C virus antibodies. The sex ...

  17. Acute HIV Discovered During Routine HIV Screening With HIV Antigen-Antibody Combination Tests in 9 US Emergency Departments.

    Science.gov (United States)

    White, Douglas A E; Giordano, Thomas P; Pasalar, Siavash; Jacobson, Kathleen R; Glick, Nancy R; Sha, Beverly E; Mammen, Priya E; Hunt, Bijou R; Todorovic, Tamara; Moreno-Walton, Lisa; Adomolga, Vincent; Feaster, Daniel J; Branson, Bernard M

    2018-01-05

    Newer combination HIV antigen-antibody tests allow detection of HIV sooner after infection than previous antibody-only immunoassays because, in addition to HIV-1 and -2 antibodies, they detect the HIV-1 p24 antigen, which appears before antibodies develop. We determine the yield of screening with HIV antigen-antibody tests and clinical presentations for new diagnoses of acute and established HIV infection across US emergency departments (EDs). This was a retrospective study of 9 EDs in 6 cities with HIV screening programs that integrated laboratory-based antigen-antibody tests between November 1, 2012, and December 31, 2015. Unique patients with newly diagnosed HIV infection were identified and classified as having either acute HIV infection or established HIV infection. Acute HIV infection was defined as a repeatedly reactive antigen-antibody test result, a negative HIV-1/HIV-2 antibody differentiation assay, or Western blot result, but detectable HIV ribonucleic acid (RNA); established HIV infection was defined as a repeatedly reactive antigen-antibody test result and a positive HIV-1/HIV-2 antibody differentiation assay or Western blot result. The primary outcomes were the number of new HIV diagnoses and proportion of patients with laboratory-defined acute HIV infection. Secondary outcomes compared reason for visit and the clinical presentation of acute HIV infection. In total, 214,524 patients were screened for HIV and 839 (0.4%) received a new diagnosis, of which 122 (14.5%) were acute HIV infection and 717 (85.5%) were established HIV infection. Compared with patients with established HIV infection, those with acute HIV infection were younger, had higher RNA and CD4 counts, and were more likely to have viral syndrome (41.8% versus 6.5%) or fever (14.3% versus 3.4%) as their reason for visit. Most patients with acute HIV infection displayed symptoms attributable to acute infection (median symptom count 5 [interquartile range 3 to 6]), with fever often

  18. Performance evaluation of a new fourth-generation HIV combination antigen-antibody assay.

    Science.gov (United States)

    Mühlbacher, A; Schennach, H; van Helden, J; Hebell, T; Pantaleo, G; Bürgisser, P; Cellerai, C; Permpikul, P; Rodriguez, M I; Eiras, A; Alborino, F; Cunningham, P; Axelsson, M; Andersson, S; Wetlitzky, O; Kaiser, C; Möller, P; de Sousa, G

    2013-02-01

    Education and diagnostic tests capable of early detection represent our most effective means of preventing transmission of human immunodeficiency virus (HIV). The importance of early detection is underlined by studies demonstrating increased life expectancy following early initiation of antiviral treatment. The Elecsys(®) HIV combi PT assay is a fourth-generation antigen-antibody combination assay developed to allow earlier detection of seroconversion, and to have increased sensitivity and improved specificity. We aimed to determine how early the assay could detect infection compared with existing assays; whether all HIV variants could be detected; and the assay's specificity using samples from blood donors, routine specimens, and patients with potential cross-reacting factors. Samples were identified as positive by the Elecsys(®) assay 4.9 days after a positive polymerase chain reaction result (as determined by the panel supplier), which was earlier than the 5.3-7.1 days observed with comparators. The analytical sensitivity of the Elecsys(®) HIV combi PT assay for the HIV-1 p24 antigen was 1.05 IU/mL, which compares favorably with the comparator assays. In addition, the Elecsys(®) assay identified all screened HIV subtypes and displayed greater sensitivity to HIV-2 homologous antigen and antibodies to HIV-1 E and O and HIV-2 than the other assays. Overall, the specificity of the Elecsys(®) assay was 99.88 % using samples from blood donors and 99.81 % when analyzing unselected samples. Potential cross-reacting factors did not interfere with assay performance. The Elecsys(®) HIV combi PT assay is a sensitive and specific assay that has been granted the CE mark according to Directive 2009/886/EC.

  19. Dendritic cells cross-present HIV antigens from live as well as apoptotic infected CD4+ T lymphocytes.

    Science.gov (United States)

    Marañón, Concepción; Desoutter, Jean-François; Hoeffel, Guillaume; Cohen, William; Hanau, Daniel; Hosmalin, Anne

    2004-04-20

    A better understanding of the antigen presentation pathways that lead to CD8(+) T cell recognition of HIV epitopes in vivo is needed to achieve better immune control of HIV replication. Here, we show that cross-presentation of very small amounts of HIV proteins from apoptotic infected CD4(+) T lymphocytes by dendritic cells to CD8(+) T cells is much more efficient than other known HIV presentation pathways, i.e., direct presentation of infectious virus or cross-presentation of defective virus. Unexpectedly, dendritic cells also take up actively antigens into endosomes from live infected CD4(+) T lymphocytes and cross-present them as efficiently as antigens derived from apoptotic infected cells. Moreover, live infected CD4(+) T cells costimulate cross-presenting dendritic cells in the process. Therefore, dendritic cells can present very small amounts of viral proteins from infected T cells either after apoptosis, which is frequent during HIV infection, or not. Thus, if HIV expression is transiently induced while costimulation is enhanced (for instance after IL-2 and IFNalpha immune therapy), this HIV antigen presentation pathway could be exploited to eradicate latently infected reservoirs, which are poorly recognized by patients' immune systems.

  20. Selection of antigenically advanced variants of seasonal influenza viruses

    NARCIS (Netherlands)

    Li, C. (Chengjun); Hatta, M. (Masato); D.F. Burke (David); Ping, J. (Jihui); Zhang, Y. (Ying); Ozawa, M. (Makoto); Taft, A.S. (Andrew S.); Das, S.C. (Subash C.); Hanson, A.P. (Anthony P.); Song, J. (Jiasheng); M. Imai; Wilker, P.R. (Peter R.); Watanabe, T. (Tokiko); Watanabe, S. (Shinji); Ito, M. (Mutsumi); Iwatsuki-Horimoto, K. (Kiyoko); C.A. Russell (Colin); S.L. James (Sarah ); E. Skepner (Eugene); E. Maher (Eileen); G. Neumann (Gabriele); A. Klimov (Alexander); A. Kelso; McCauley, J. (John); D. Wang (Dayan); Y.L. Shu (Yue-Long); T. Odagiri (Takato); Tashiro, M. (Masato); X. Xu (Xiyan); Wentworth, D.E. (David E.); J. Katz (Jacqueline); N.J. Cox (Nancy); D.J. Smith (Derek James); Y. Kawaoka (Yoshihiro)

    2016-01-01

    textabstractInfluenza viruses mutate frequently, necessitating constant updates of vaccine viruses. To establish experimental approaches that may complement the current vaccine strain selection process, we selected antigenic variants from human H1N1 and H3N2 influenza virus libraries possessing

  1. 110 HUMAN IMMUNODEFICIENCY VIRUS (HIV) SEROPOSITIVITY ...

    African Journals Online (AJOL)

    ABSTRACT. A seroprevalence study of Human immunodeficiency virus (HIV) infection in new patients attending the eye clinic of LAUTECH. Teaching Hospital in Osogbo, Osun State, Nigeria showed that twenty-nine patients 2.7%) were positive to HIV1. No patient was positive to HIV 2. There were 21 males (72.4%) and 8 ...

  2. Human Leukocyte Antigen (HLA Class I Down-Regulation by Human Immunodeficiency Virus Type 1 Negative Factor (HIV-1 Nef: What Might We Learn From Natural Sequence Variants?

    Directory of Open Access Journals (Sweden)

    Philip Mwimanzi

    2012-09-01

    Full Text Available HIV-1 causes a chronic infection in humans that is characterized by high plasma viremia, progressive loss of CD4+ T lymphocytes, and severe immunodeficiency resulting in opportunistic disease and AIDS. Viral persistence is mediated in part by the ability of the Nef protein to down-regulate HLA molecules on the infected cell surface, thereby allowing HIV-1 to evade recognition by antiviral CD8+ T lymphocytes. Extensive research has been conducted on Nef to determine protein domains that are required for its immune evasion activities and to identify critical cellular co-factors, and our mechanistic understanding of this process is becoming more complete. This review highlights our current knowledge of Nef-mediated HLA class I down-regulation and places this work in the context of naturally occurring sequence variation in this protein. We argue that efforts to fully understand the critical role of Nef for HIV-1 pathogenesis will require greater analysis of patient-derived sequences to elucidate subtle differences in immune evasion activity that may alter clinical outcome.

  3. Insertion of vaccinia virus C7L host range gene into NYVAC-B genome potentiates immune responses against HIV-1 antigens

    National Research Council Canada - National Science Library

    Nájera, José Luis; Gómez, Carmen Elena; García-Arriaza, Juan; Sorzano, Carlos Oscar; Esteban, Mariano

    2010-01-01

    ... while maintaining an attenuated phenotype in mice. In an effort to improve the immunogenicity of NYVAC, we have developed a novel poxvirus vector by inserting the VACV host-range C7L gene into the genome of NYVAC-B, a recombinant virus that expresses...

  4. Chimeric antigen receptor engineered stem cells: a novel HIV therapy.

    Science.gov (United States)

    Zhen, Anjie; Carrillo, Mayra A; Kitchen, Scott G

    2017-03-01

    Despite the success of combination antiretroviral therapy (cART) for suppressing HIV and improving patients' quality of life, HIV persists in cART-treated patients and remains an incurable disease. Financial burdens and health consequences of lifelong cART treatment call for novel HIV therapies that result in a permanent cure. Cellular immunity is central in controlling HIV replication. However, HIV adopts numerous strategies to evade immune surveillance. Engineered immunity via genetic manipulation could offer a functional cure by generating cells that have enhanced antiviral activity and are resistant to HIV infection. Recently, encouraging reports from several human clinical trials using an anti-CD19 chimeric antigen receptor (CAR) modified T-cell therapy for treating B-cell malignancies have provided valuable insights and generated remarkable enthusiasm in engineered T-cell therapy. In this review, we discuss the development of HIV-specific chimeric antigen receptors and the use of stem cell based therapies to generate lifelong anti-HIV immunity.

  5. Selection of antigenically advanced variants of seasonal influenza viruses

    Science.gov (United States)

    Ozawa, Makoto; Taft, Andrew S.; Das, Subash C.; Hanson, Anthony P.; Song, Jiasheng; Imai, Masaki; Wilker, Peter R.; Watanabe, Tokiko; Watanabe, Shinji; Ito, Mutsumi; Iwatsuki-Horimoto, Kiyoko; Russell, Colin A.; James, Sarah L.; Skepner, Eugene; Maher, Eileen A.; Neumann, Gabriele; Kelso, Anne; McCauley, John; Wang, Dayan; Shu, Yuelong; Odagiri, Takato; Tashiro, Masato; Xu, Xiyan; Wentworth, David E.; Katz, Jacqueline M.; Cox, Nancy J.; Smith, Derek J.; Kawaoka, Yoshihiro

    2016-01-01

    Influenza viruses mutate frequently, necessitating constant updates of vaccine viruses. To establish experimental approaches that may complement the current vaccine strain selection process, we selected antigenic variants from human H1N1 and H3N2 influenza virus libraries possessing random mutations in the globular head of the haemagglutinin protein (which includes the antigenic sites) by incubating them with human and/or ferret convalescent sera to human H1N1 and H3N2 viruses. Further, we selected antigenic escape variants from human viruses treated with convalescent sera and from mice that had been previously immunized against human influenza viruses. Our pilot studies with past influenza viruses identified escape mutants that were antigenically similar to variants that emerged in nature, establishing the feasibility of our approach. Our studies with contemporary human influenza viruses identified escape mutants before they caused an epidemic in 2014–2015. This approach may aid in the prediction of potential antigenic escape variants and the selection of future vaccine candidates before they become widespread in nature. PMID:27572841

  6. Single hemagglutinin mutations that alter both antigenicity and receptor binding avidity influence influenza virus antigenic clustering.

    Science.gov (United States)

    Li, Yang; Bostick, David L; Sullivan, Colleen B; Myers, Jaclyn L; Griesemer, Sara B; Stgeorge, Kirsten; Plotkin, Joshua B; Hensley, Scott E

    2013-09-01

    The hemagglutination inhibition (HAI) assay is the primary measurement used for identifying antigenically novel influenza virus strains. HAI assays measure the amount of reference sera required to prevent virus binding to red blood cells. Receptor binding avidities of viral strains are not usually taken into account when interpreting these assays. Here, we created antigenic maps of human H3N2 viruses that computationally account for variation in viral receptor binding avidities. These new antigenic maps differ qualitatively from conventional antigenic maps based on HAI measurements alone. We experimentally focused on an antigenic cluster associated with a single N145K hemagglutinin (HA) substitution that occurred between 1992 and 1995. Reverse-genetics experiments demonstrated that the N145K HA mutation increases viral receptor binding avidity. Enzyme-linked immunosorbent assays (ELISA) revealed that the N145K HA mutation does not prevent antibody binding; rather, viruses possessing this mutation escape antisera in HAI assays simply by attaching to cells more efficiently. Unexpectedly, we found an asymmetric antigenic effect of the N145K HA mutation. Once H3N2 viruses acquired K145, an epitope involving amino acid 145 became antigenically dominant. Antisera raised against an H3N2 strain possessing K145 had reduced reactivity to H3N2 strains possessing N145. Thus, individual mutations in HA can influence antigenic groupings of strains by altering receptor binding avidity and by changing the dominance of antibody responses. Our results indicate that it will be important to account for variation in viral receptor binding avidity when performing antigenic analyses in order to identify genuine antigenic differences among influenza virus variants.

  7. HIV antigen incorporation within adenovirus hexon hypervariable 2 for a novel HIV vaccine approach.

    Directory of Open Access Journals (Sweden)

    Qiana L Matthews

    2010-07-01

    Full Text Available Adenoviral (Ad vectors have been used for a variety of vaccine applications including cancer and infectious diseases. Traditionally, Ad-based vaccines are designed to express antigens through transgene expression of a given antigen. However, in some cases these conventional Ad-based vaccines have had sub-optimal clinical results. These sub-optimal results are attributed in part to pre-existing Ad serotype 5 (Ad5 immunity. In order to circumvent the need for antigen expression via transgene incorporation, the "antigen capsid-incorporation" strategy has been developed and used for Ad-based vaccine development in the context of a few diseases. This strategy embodies the incorporation of antigenic peptides within the capsid structure of viral vectors. The major capsid protein hexon has been utilized for these capsid incorporation strategies due to hexon's natural role in the generation of anti-Ad immune response and its numerical representation within the Ad virion. Using this strategy, we have developed the means to incorporate heterologous peptide epitopes specifically within the major surface-exposed domains of the Ad capsid protein hexon. Our study herein focuses on generation of multivalent vaccine vectors presenting HIV antigens within the Ad capsid protein hexon, as well as expressing an HIV antigen as a transgene. These novel vectors utilize HVR2 as an incorporation site for a twenty-four amino acid region of the HIV membrane proximal ectodomain region (MPER, derived from HIV glycoprotein gp41 (gp41. Our study herein illustrates that our multivalent anti-HIV vectors elicit a cellular anti-HIV response. Furthermore, vaccinations with these vectors, which present HIV antigens at HVR2, elicit a HIV epitope-specific humoral immune response.

  8. HIV-1 Activates T Cell Signaling Independently of Antigen to Drive Viral Spread.

    Science.gov (United States)

    Len, Alice C L; Starling, Shimona; Shivkumar, Maitreyi; Jolly, Clare

    2017-01-24

    HIV-1 spreads between CD4 T cells most efficiently through virus-induced cell-cell contacts. To test whether this process potentiates viral spread by activating signaling pathways, we developed an approach to analyze the phosphoproteome in infected and uninfected mixed-population T cells using differential metabolic labeling and mass spectrometry. We discovered HIV-1-induced activation of signaling networks during viral spread encompassing over 200 cellular proteins. Strikingly, pathways downstream of the T cell receptor were the most significantly activated, despite the absence of canonical antigen-dependent stimulation. The importance of this pathway was demonstrated by the depletion of proteins, and we show that HIV-1 Env-mediated cell-cell contact, the T cell receptor, and the Src kinase Lck were essential for signaling-dependent enhancement of viral dissemination. This study demonstrates that manipulation of signaling at immune cell contacts by HIV-1 is essential for promoting virus replication and defines a paradigm for antigen-independent T cell signaling. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  9. Nonvirion Antigens Produced by Herpes Simplex Viruses 1 and 2

    Science.gov (United States)

    Tarro, Giulio; Sabin, Albert B.

    1973-01-01

    Of nine herpes simplex virus 1 strains (from lip, mouth, throat, cornea, or brain) only five produced enough nonvirion antigen (i.e., not a structural component of the virus) to be detected by complement fixation with specially prepared, virion-absorbed, type-1 guinea pig antisera, while the remaining four strains produced only enough of the same antigen to induce specific antibody in hyperimmunized guinea pigs. While the type 1 virion antiserum used reacted equally well by complement fixation with the type 1 and type 2 strains, the type 1 nonvirion antisera failed to react with nonvirion antigens produced by three type-2 (genital) strains. However, type 2 nonvirion antiserum reacted equally well with the three type 2 and four type 1 nonvirion antigens that were tested. It appears, therefore, that while herpes simplex virus 1 codes only for type 1 nonvirion antigen, herpes simplex 2 codes not only for an immunologically distinct type 2 nonvirion antigen but also for enough type 1 nonvirion antigen to stimulate antibody production for it. Herpes simplex 2 nonvirion antigen exhibited the same properties as type 1, i.e., its activity was lost on storage at 4° for 15 days, it was sedimented by centrifugation at 33,360 × g for 1 hr, and the maximum concentration was found at 3 hr in guinea pig kidney culture cells, but at 24 hr in HEp 2 and rabbit kidney culture cells. Sera from patients with genital lesions caused by herpes simplex virus 2, as well as from randomly selected adults, failed to react with either type 2 or type 1 nonvirion antigens. Accordingly, the basic information is now available to permit the use of these nonvirion antigens to determine the possible role of the herpes simplex viruses in certain human cancers. PMID:4352219

  10. Prevalence of hepatitis B surface antigen seropositivity among HIV ...

    African Journals Online (AJOL)

    Hepatitis B surface antigen (HBsAg) was tested for using a one step lateral flow rapid chromatographic immunoassay (Acumen labs and diagnostic centre, Bangalore, India) and HIV 1/2 was tested using two kits, Determine (made by Abbot, Japan for Inverness Medical, Japan). Results: A total of 2018 subjects were studied ...

  11. HIV-1 Trans Infection of CD4+ T Cells by Professional Antigen Presenting Cells

    Science.gov (United States)

    Rinaldo, Charles R.

    2013-01-01

    Since the 1990s we have known of the fascinating ability of a complex set of professional antigen presenting cells (APCs; dendritic cells, monocytes/macrophages, and B lymphocytes) to mediate HIV-1 trans infection of CD4+ T cells. This results in a burst of virus replication in the T cells that is much greater than that resulting from direct, cis infection of either APC or T cells, or trans infection between T cells. Such APC-to-T cell trans infection first involves a complex set of virus subtype, attachment, entry, and replication patterns that have many similarities among APC, as well as distinct differences related to virus receptors, intracellular trafficking, and productive and nonproductive replication pathways. The end result is that HIV-1 can sequester within the APC for several days and be transmitted via membrane extensions intracellularly and extracellularly to T cells across the virologic synapse. Virus replication requires activated T cells that can develop concurrently with the events of virus transmission. Further research is essential to fill the many gaps in our understanding of these trans infection processes and their role in natural HIV-1 infection. PMID:24278768

  12. Temporal relation of antigenaemia and loss of antibodies to core antigens to development of clinical disease in HIV infection

    DEFF Research Database (Denmark)

    Pedersen, C; Nielsen, C M; Vestergaard, B F

    1987-01-01

    A total of 276 sequential serum samples from 34 men with antibodies to the human immunodeficiency virus (HIV) followed up for two to seven years were analysed for HIV antigen and antibodies to the viral core and envelope proteins. Results were correlated with clinical outcome and CD4 T lymphocyte...... and 16 months after the estimated time of seroconversion. These results show that the late stages of HIV infection are characterised by increased production of antigen and a decrease in antibodies directed against the core protein. Antigenaemia indicates a poor prognosis; and as the antigen test...... count. Both antigenaemia and the disappearance of antibodies to the core protein were associated with development of the acquired immune deficiency syndrome (AIDS) or AIDS related complex and depletion of CD4 cells. Thus AIDS or AIDS related complex developed in eight out of 16 patients...

  13. Intra-Blood-Brain Barrier Synthesis of Human Immunodeficiency Virus Antigen and Antibody in Humans and Chimpanzees

    Science.gov (United States)

    Goudsmit, Jaap; Epstein, Leon G.; Paul, Deborah A.; van der Helm, Hayo J.; Dawson, George J.; Asher, David M.; Yanagihara, Richard; Wolff, Axel V.; Gibbs, Clarence J.; Carleton Gajdusek, D.

    1987-06-01

    The presence of human immunodeficiency virus (HIV) antigens in cerebrospinal fluid (CSF) was associated with progressive encephalopathy in adult and pediatric patients with acquired immunodeficiency syndrome (AIDS). HIV antigen was detected in CSF from 6 of 7 AIDS patients with progressive encephalopathy. By contrast, HIV antigen, whether free or complexed, was detected in CSF from only 1 of 18 HIV antibody seropositive patients without progressive encephalopathy and from 0 of 8 experimentally infected chimpanzees without clinical signs. Intra-blood-brain barrier synthesis of HIV-specific antibody was demonstrated in the majority of patients with AIDS (9/12) or at risk for AIDS (8/13) as well as in the experimentally infected chimpanzees, indicating HIV-specific B-cell reactivity in the brain without apparent neurological signs. In 6 of 11 patients with HIV infection, antibodies synthesized in the central nervous system were directed against HIV envelope proteins. Active viral expression appears to be necessary for both the immunodeficiency and progressive encephalopathy associated with HIV infection.

  14. Cost-effectiveness of a fourth-generation combination immunoassay for human immunodeficiency virus (HIV) antibody and p24 antigen for the detection of HIV infections in the United States.

    Science.gov (United States)

    Cragin, Lael; Pan, Feng; Peng, Siyang; Zenilman, Jonathan M; Green, Julia; Doucet, Cynthia; Chalfin, Donald B; de Lissovoy, Greg

    2012-01-01

    The US Food and Drug Administration recently approved the first 4th-generation HIV test. This study evaluated the cost-effectiveness of the 4th-generation assay versus a 3rd-generation test in screening for HIV infections in the United States. An exploratory microsimulation model was developed that follows hypothetical individuals and simulates the course of HIV/AIDS, treatment with highly active antiretroviral therapy, and transmissions. With a 1% HIV prevalence, screening 1.5 million individuals with the 4th- versus 3rd-generation assay resulted in detection of 266 additional HIV cases at an incremental cost per additional HIV case detected of $63,763, an additional 489 life years and 395 quality-adjusted life years (QALYs), and 26 HIV transmissions prevented. Although lifetime costs were increased by $33.6 million, the incremental cost/QALY gained was $85,206. The 4th-generation test was more cost-effective in high incidence settings. The number needed to screen to detect one additional HIV case was 5,635. Screening using the 4th-generation assay may be cost-effective for HIV detection in appropriate settings, resulting in increased case identification, fewer transmissions, extended life, and increased quality of life. With early and accurate detection, this 4th-generation test may provide a suitable alternative to current 3rd-generation tests.

  15. Clinical characteristics of Human Immunodeficiency Virus (HIV ...

    African Journals Online (AJOL)

    Renal failure is a common finding in human immunodeficiency virus infected patients, and it contributes significantly to their morbidity and mortality. Most dialysis centres in Nigeria currently do not accept HIV positive patients for dialysis therapy for many reasons. The prevailing high level of stigmatization of HIV positive ...

  16. αEnv-decorated phosphatidylserine liposomes trigger phagocytosis of HIV-virus-like particles in macrophages.

    Science.gov (United States)

    Gramatica, Andrea; Petazzi, Roberto A; Lehmann, Maik J; Ziomkowska, Joanna; Herrmann, Andreas; Chiantia, Salvatore

    2014-07-01

    Macrophages represent an important cellular target of HIV-1. Interestingly, they are also believed to play a potential role counteracting its infection. However, HIV-1 is known to impair macrophage immune functions such as antibody-mediated phagocytosis. Here, we present immunoliposomes that can bind HIV-1 virus-like particles (HIV-VLPs) while being specifically phagocytosed by macrophages, thus allowing the co-internalization of HIV-VLPs. These liposomes are decorated with anti-Env antibodies and contain phosphatidylserine (PS). PS mediates liposome internalization by macrophages via a mechanism not affected by HIV-1. Hence, PS-liposomes mimic apoptotic cells and are internalized into the macrophages due to specific recognition, carrying the previously bound HIV-VLPs. With a combination of flow cytometry, confocal live-cell imaging and electron microscopy we demonstrate that the PS-immunoliposomes presented here are able to elicit efficient HIV-VLPs phagocytosis by macrophages and might represent a new nanotechnological approach to enhance HIV-1 antigen presentation and reduce the ongoing inflammation processes. This team of authors demonstrate that specific phosphatidylserin immunoliposomes are able to elicit efficient phagocytosis of HIV-virus-like particle by macrophages and might represent a new nanomedicine approach to enhance HIV-1 antigen presentation and reduce ongoing inflammation processes. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Immunoglobulin response to bluetongue virus soluble antigen in subcutaneous chambers.

    Science.gov (United States)

    Hajer, I; Jochim, M M; Lauerman, L H

    1977-06-01

    Group-specific antibodies were produced by inoculation of bluetongue virus soluble antigen into polyethylene chambers implanted subcutaneously in 8 rabbits and 2 sheep. For comparison, 5 rabbits and 1 sheep were inoculated intramuscularly with the soluble antigen in Freund's complete adjuvant. Antibodies present in the serum and chamber fluids were detected by the agar gel precipitin or serum-neutralization tests, qualitatively examined by immunoelectrophoresis and immunofluorescence, and quantitated by electroimmunodiffusion.

  18. Critical role for the chemokine receptor CXCR6 in NK cell-mediated antigen-specific memory of haptens and viruses.

    Science.gov (United States)

    Paust, Silke; Gill, Harvinder S; Wang, Bao-Zhong; Flynn, Michael P; Moseman, E Ashley; Senman, Balimkiz; Szczepanik, Marian; Telenti, Amalio; Askenase, Philip W; Compans, Richard W; von Andrian, Ulrich H

    2010-12-01

    Hepatic natural killer (NK) cells mediate antigen-specific contact hypersensitivity (CHS) in mice deficient in T cells and B cells. We report here that hepatic NK cells, but not splenic or naive NK cells, also developed specific memory of vaccines containing antigens from influenza, vesicular stomatitis virus (VSV) or human immunodeficiency virus type 1 (HIV-1). Adoptive transfer of virus-sensitized NK cells into naive recipient mice enhanced the survival of the mice after lethal challenge with the sensitizing virus but not after lethal challenge with a different virus. NK cell memory of haptens and viruses depended on CXCR6, a chemokine receptor on hepatic NK cells that was required for the persistence of memory NK cells but not for antigen recognition. Thus, hepatic NK cells can develop adaptive immunity to structurally diverse antigens, an activity that requires NK cell-expressed CXCR6.

  19. Virus-like-vaccines against HIV

    DEFF Research Database (Denmark)

    Andersson, Anne Marie C.; Schwerdtfeger, Melanie; Holst, Peter J.

    2018-01-01

    Protection against chronic infections has necessitated the development of ever-more potent vaccination tools. HIV seems to be the most challenging foe, with a remarkable, poorly immunogenic and fragile surface glycoprotein and the ability to overpower the cell immune system. Virus-like-particle (......Protection against chronic infections has necessitated the development of ever-more potent vaccination tools. HIV seems to be the most challenging foe, with a remarkable, poorly immunogenic and fragile surface glycoprotein and the ability to overpower the cell immune system. Virus...... of HIV. Such vaccines are immunologically perceived as viruses, as they infect cells and produce VLPs in situ, but they only resemble viruses, as the replication defective vectors and VLPs cannot propagate an infection. The inherent safety of such a platform, despite robust particle production...

  20. HIV-1-Specific Chimeric Antigen Receptors Based on Broadly Neutralizing Antibodies.

    Science.gov (United States)

    Ali, Ayub; Kitchen, Scott G; Chen, Irvin S Y; Ng, Hwee L; Zack, Jerome A; Yang, Otto O

    2016-08-01

    Although the use of chimeric antigen receptors (CARs) based on single-chain antibodies for gene immunotherapy of cancers is increasing due to promising recent results, the earliest CAR therapeutic trials were done for HIV-1 infection in the late 1990s. This approach utilized a CAR based on human CD4 as a binding domain and was abandoned for a lack of efficacy. The growing number of HIV-1 broadly neutralizing antibodies (BNAbs) offers the opportunity to generate novel CARs that may be more active and revisit this modality for HIV-1 immunotherapy. We used sequences from seven well-defined BNAbs varying in binding sites and generated single-chain-antibody-based CARs. These CARs included 10E8, 3BNC117, PG9, PGT126, PGT128, VRC01, and X5. Each novel CAR exhibited conformationally relevant expression on the surface of transduced cells, mediated specific proliferation and killing in response to HIV-1-infected cells, and conferred potent antiviral activity (reduction of viral replication in log10 units) to transduced CD8(+) T lymphocytes. The antiviral activity of these CARs was reproducible but varied according to the strain of virus. These findings indicated that BNAbs are excellent candidates for developing novel CARs to consider for the immunotherapeutic treatment of HIV-1. While chimeric antigen receptors (CARs) using single-chain antibodies as binding domains are growing in popularity for gene immunotherapy of cancers, the earliest human trials of CARs were done for HIV-1 infection. However, those trials failed, and the approach was abandoned for HIV-1. The only tested CAR against HIV-1 was based on the use of CD4 as the binding domain. The growing availability of HIV-1 broadly neutralizing antibodies (BNAbs) affords the opportunity to revisit gene immunotherapy for HIV-1 using novel CARs based on single-chain antibodies. Here we construct and test a panel of seven novel CARs based on diverse BNAb types and show that all these CARs are functional against HIV-1

  1. Rapid assay for simultaneous detection and differentiation of immunoglobulin G antibodies to human immunodeficiency virus type 1 (HIV-1) group M, HIV-1 group O, and HIV-2.

    Science.gov (United States)

    Vallari, A S; Hickman, R K; Hackett, J R; Brennan, C A; Varitek, V A; Devare, S G

    1998-12-01

    A rapid immunodiagnostic test that detects and discriminates human immunodeficiency virus (HIV) infections on the basis of viral type, HIV type 1 (HIV-1) group M, HIV-1 group O, or HIV-2, was developed. The rapid assay for the detection of HIV (HIV rapid assay) was designed as an instrument-free chromatographic immunoassay that detects immunoglobulin G (IgG) antibodies to HIV. To assess the performance of the HIV rapid assay, 470 HIV-positive plasma samples were tested by PCR and/or Western blotting to confirm the genotype of the infecting virus. These samples were infected with strains that represented a wide variety of HIV strains including HIV-1 group M (subtypes A through G), HIV-1 group O, and HIV-2 (subtypes A and B). The results showed that the HIV genotype identity established by the rapid assay reliably (469 of 470 samples) correlates with the HIV genotype identity established by PCR or Western blotting. A total of 879 plasma samples were tested for IgG to HIV by a licensed enzyme immunoassay (EIA) (470 HIV-positive samples and 409 HIV-negative samples). When they were tested by the rapid assay, 469 samples were positive and 410 were negative (99.88% agreement). Twelve seroconversion panels were tested by both the rapid assay and a licensed EIA. For nine panels identical results were obtained by the two assays. For the remaining three panels, the rapid assay was positive one bleed later in comparison to the bleed at which the EIA was positive. One hundred three urine samples, including 93 urine samples from HIV-seropositive individuals and 10 urine samples from seronegative individuals, were tested by the rapid assay. Ninety-one of the ninety-three urine samples from HIV-seropositive individuals were found to be positive by the rapid assay. There were no false-positive results (98.05% agreement). Virus in all urine samples tested were typed as HIV-1 group M. These results suggest that a rapid assay based on the detection of IgG specific for selected

  2. Recombinant envelope protein of HIV-1 subtype E as antigen in HIV-1 antibody detection enzyme immunoassay.

    Science.gov (United States)

    Sutthent, Ruengpung; Kanoksinsombat, Chinda; Horthongkham, Navin; Louisirirotchanakul, Suda; Auewarakul, Prasert; Kantakamalakul, Wannee

    2002-06-01

    In order to develop a reliable and inexpensive serodiagnostic method to be used for anti-HIV antibody detection in Thailand, recombinant envelope (TM or gp41 subunit) protein of HIV-1 subtype E was produced from prokaryotic cell (Escherichia coli) as the source of antigen in enzyme immunoassay (TE diagnostic EIA kit). HIV-1 gp41 subunit of subtype E was successfully expressed in E. coli in the form of polyhistidine-tagged proteins, comprising of rgp41A (601 bases N-terminal half of TM or 25kDa) and rgp41B (560 bases C-terminal half of TM or 24 kDa) by using an expression vector, pBAD/His C. The amount of protein, dilution of sera, and anti-human IgG labeled HRP used in the EIA test optimized by a checker board titration of the protein and seropositive or seronegative sera, were 5.0 microg/ml, 1:300, and 1:4,000, respectively. The blinded test evaluation of TE-diagnostic EIA in 500 seropositive and 500 seronegative sera which have been simultaneously tested by two available commercial kits and compared with our TE diagnostic EIA, gave 99.6% sensitivity and specificity. The other known genetic subtypes sera such as subtype A (n=5), B (n=9), C (n=4) and D (n=5) were also positive with this EIA. The estimated manufacturer cost per test of rgp41 based anti-HIV antibody detection EIA or TE-diagnostic EIA was about 15 baht. This recombinant envelope (gp41 or TM) protein from HIV-1, which can be produced in large quantities without any hazards from growing the virus and has lower cost to produce anti-HIV antibody serological diagnostic kit, should be considered as an HIV screening test in Thailand.

  3. The role of triple infection with hepatitis B virus, hepatitis C virus, and human immunodeficiency virus (HIV type-1 on CD4+ lymphocyte levels in the highly HIV infected population of North-Central Nigeria

    Directory of Open Access Journals (Sweden)

    JC Forbi

    2007-06-01

    Full Text Available We set out to determine the seroprevalence of hepatitis B and C among human immunodeficiency virus type-1 (HIV-1 infected individuals in North-Central Nigeria to define the influence of these infections on CD4+ lymphocytes cells among our patients as access to antiretroviral therapy improves across the Nigerian nation. The CD4+ values of 180 confirmed HIV-1 infected individuals were enumerated using a superior fluorescence-activated cell sorter system. These patients were tested for the presence of hepatitis B surface antigen and anti-hepatitis C virus (HCV using third generation enzyme-linked immunosorbent assays. Fifty (27.8% patients had active hepatitis B virus (HBV infection while 33 (18.3% tested positive for anti-HCV antibody. Of these infections, 110 (61.1%, 37 (20.6%, and 20 (11.1% had HIV only, HBV/HIV-only, and HCV/HIV-only respectively. A HBV/HCV/HIV coinfection prevalence of 7.2% (13 patients was recorded. Patients coinfected with HIV/HBV/HCV appeared to have lower CD4+ counts (mean = 107 cells/µl; AIDS defining when compared to HBV/HIV-only (mean = 377 cells/µl, HCV/HIV-only (mean = 373 cells/µl and patients with mono HIV infection (mean = 478 cells/µl. Coinfection with HBV or HCV is relatively common among HIV-infected patients in Nigeria and should be a big consideration in the initiation and choice of therapy.

  4. The role of triple infection with hepatitis B virus, hepatitis C virus, and human immunodeficiency virus (HIV) type-1 on CD4+ lymphocyte levels in the highly HIV infected population of North-Central Nigeria.

    Science.gov (United States)

    Forbi, J C; Gabadi, S; Alabi, R; Iperepolu, H O; Pam, C R; Entonu, P E; Agwale, S M

    2007-06-01

    We set out to determine the seroprevalence of hepatitis B and C among human immunodeficiency virus type-1 (HIV-1) infected individuals in North-Central Nigeria to define the influence of these infections on CD4+ lymphocytes cells among our patients as access to antiretroviral therapy improves across the Nigerian nation. The CD4+ values of 180 confirmed HIV-1 infected individuals were enumerated using a superior fluorescence-activated cell sorter system. These patients were tested for the presence of hepatitis B surface antigen and anti-hepatitis C virus (HCV) using third generation enzyme-linked immunosorbent assays. Fifty (27.8%) patients had active hepatitis B virus (HBV) infection while 33 (18.3%) tested positive for anti-HCV antibody. Of these infections, 110 (61.1%), 37 (20.6%), and 20 (11.1%) had HIV only, HBV/HIV-only, and HCV/HIV-only respectively. A HBV/HCV/HIV coinfection prevalence of 7.2% (13 patients) was recorded. Patients coinfected with HIV/HBV/HCV appeared to have lower CD4+ counts (mean = 107 cells/microl; AIDS defining) when compared to HBV/HIV-only (mean = 377 cells/microl), HCV/HIV-only (mean = 373 cells/microl) and patients with mono HIV infection (mean = 478 cells/microl). Coinfection with HBV or HCV is relatively common among HIV-infected patients in Nigeria and should be a big consideration in the initiation and choice of therapy.

  5. Localization of human immunodeficiency virus antigens in infected cells by scanning/transmission-immunogold techniques

    Energy Technology Data Exchange (ETDEWEB)

    Herrera, M.I.; Santa Maria, I.; de Andres, R.; Najera, R.

    1988-01-01

    An application of high resolution scanning/transmission electron microscopy (STEM) and gold-labelling techniques for the rapid detection of human immunodeficiency virus (HIV) in infected cells has been developed. Experimental in vitro studies for detecting two HIV structural proteins, gp41 and p17, were performed following an indirect labeling procedure that uses monoclonal anti-p17 and anti-gp41 antibodies as primary antibodies and 40 nm gold-linked goat antimouse IgG as secondary antibodies. The cells were then studied by STEM in the scanning mode. Unambiguous localization of the viral antigens was possible by combining the three-dimensional image provided by the secondary electron image and the atomic number-dependent backscattered electron image for the identification of the gold marker. This technique combines both the morphological information and the rapid procedures of scanning electron microscopy with the precise and sensitive antigen detection provided by the use of STEM and immunological methods. The preliminary results of its application to the study of peripheral blood mononuclear cells from four anti-HIV-seropositive patients showing the presence of specific labeling in all of them suggest that it might prove useful for early detection of HIV infection before seroconversion, as well as for quantitative studies.

  6. Decline of HIV antigen levels in cerebrospinal fluid during treatment with low-dose zidovudine

    NARCIS (Netherlands)

    de Gans, J.; Lange, J. M.; Derix, M. M.; de Wolf, F.; Eeftinck Schattenkerk, J. K.; Danner, S. A.; Ongerboer de Visser, B. W.; Cload, P.; Goudsmit, J.

    1988-01-01

    Six HIV-antigenaemic patients with AIDS or AIDS-related complex were studied to assess the effect of treatment with low-dose zidovudine (250 mg) in 6-hourly doses on HIV antigen (HIV-Ag) levels in cerebrospinal fluid (CSF). HIV-Ag was detected in CSF of three patients before treatment. These

  7. Escherichia coli–expressed near full length HIV-1 envelope glycoprotein is a highly sensitive and specific diagnostic antigen

    Directory of Open Access Journals (Sweden)

    Talha Sheikh M

    2012-11-01

    Full Text Available Abstract Background The Human Immunodeficiency Virus type 1 (HIV-1 envelope glycoprotein gp160, useful in detecting anti-HIV-1 antibodies, is difficult to express in heterologous hosts. The major hurdles are its signal sequence, strong hydrophobic regions and heavy glycosylation. While it has not been possible to express full length recombinant (r-gp160 in E. coli, it can be expressed in insect and mammalian cells, but at relatively higher cost. In this work, we report E. coli-based over-expression of r-gp160 variant and evaluate its performance in diagnostic immunoassays for the detection of anti-HIV-1 antibodies. Methods A deletion variant of r-gp160 lacking hydrophobic regions of the parent full length molecule was expressed in E. coli and purified to near homogeneity using single-step Ni(II-affinity chromatography. Biotinylated and europium(III chelate-labeled versions of this antigen were used to set up one- and two-step time-resolved fluorometric double antigen sandwich assays. The performance of these assays was evaluated against a collection of well-characterized human sera (n=131, that included an in-house panel and four commercially procured panels. Results In-frame deletion of three hydrophobic regions, spanning amino acid residues 1–43, 519–538 and 676–706, of full length HIV-1 gp160 resulted in its expression in E. coli. Both the one- and two-step assays manifested high sensitivity unambiguously identifying 75/77 and 77/77 HIV-1 positive sera, respectively. Both assays also identified all 52 HIV-seronegative sera correctly. Between the two assays, the mean signal-to-cutoff value of the two-step assay was an order of magnitude greater than that of the one-step assay. Both assays were highly specific manifesting no cross-reactivity towards antibodies specific to other viruses like hepatitis B, C, and human T cell leukemia viruses. Conclusions This study has demonstrated the expression of r-gp160 variant in E. coli, by deletion

  8. Failure of a novel, rapid antigen and antibody combination test to detect antigen-positive HIV infection in African adults with early HIV infection.

    Directory of Open Access Journals (Sweden)

    William Kilembe

    Full Text Available BACKGROUND: Acute HIV infection (prior to antibody seroconversion represents a high-risk window for HIV transmission. Development of a test to detect acute infection at the point-of-care is urgent. METHODS: Volunteers enrolled in a prospective study of HIV incidence in four African cities, Kigali in Rwanda and Ndola, Kitwe and Lusaka in Zambia, were tested regularly for HIV by rapid antibody test and p24 antigen ELISA. Five subgroups of samples were also tested by the Determine Ag/Ab Combo test 1 Antigen positive, antibody negative (acute infection; 2 Antigen positive, antibody positive; 3 Antigen negative, antibody positive; 4 Antigen negative, antibody negative; and 5 Antigen false positive, antibody negative (HIV uninfected. A sixth group included serial dilutions from a p24 antigen-positive control sample. Combo test results were reported as antigen positive, antibody positive, or both. RESULTS: Of 34 group 1 samples with VL between 5x105 and >1.5x107 copies/mL (median 3.5x106, 1 (2.9% was detected by the Combo antigen component, 7 (20.6% others were positive by the Combo antibody component. No group 2 samples were antigen positive by the Combo test (0/18. Sensitivity of the Combo antigen test was therefore 1.9% (1/52, 95% CI 0.0, 9.9. One false positive Combo antibody result (1/30, 3.3% was observed in group 4. No false-positive Combo antigen results were observed. The Combo antigen test was positive in group 6 at concentrations of 80 pg/mL, faintly positive at 40 and 20 pg/mL, and negative thereafter. The p24 ELISA antigen test remained positive at 5 pg/mL. CONCLUSIONS: Although the antibody component of the Combo test detected antibodies to HIV earlier than the comparison antibody tests used, less than 2% of the cases of antigen-positive HIV infection were detected by the Combo antigen component. The development of a rapid point-of-care test to diagnose acute HIV infection remains an urgent goal.

  9. Failure of a novel, rapid antigen and antibody combination test to detect antigen-positive HIV infection in African adults with early HIV infection.

    Science.gov (United States)

    Kilembe, William; Keeling, Michelle; Karita, Etienne; Lakhi, Shabir; Chetty, Paramesh; Price, Matt A; Makkan, Heeran; Latka, Mary; Likoti, Morongwe; Ilukui, Kenneth; Hurlston, Mackenzie; Allen, Susan; Stevens, Gwynn; Hunter, Eric

    2012-01-01

    Acute HIV infection (prior to antibody seroconversion) represents a high-risk window for HIV transmission. Development of a test to detect acute infection at the point-of-care is urgent. Volunteers enrolled in a prospective study of HIV incidence in four African cities, Kigali in Rwanda and Ndola, Kitwe and Lusaka in Zambia, were tested regularly for HIV by rapid antibody test and p24 antigen ELISA. Five subgroups of samples were also tested by the Determine Ag/Ab Combo test 1) Antigen positive, antibody negative (acute infection); 2) Antigen positive, antibody positive; 3) Antigen negative, antibody positive; 4) Antigen negative, antibody negative; and 5) Antigen false positive, antibody negative (HIV uninfected). A sixth group included serial dilutions from a p24 antigen-positive control sample. Combo test results were reported as antigen positive, antibody positive, or both. Of 34 group 1 samples with VL between 5x105 and >1.5x107 copies/mL (median 3.5x106), 1 (2.9%) was detected by the Combo antigen component, 7 (20.6%) others were positive by the Combo antibody component. No group 2 samples were antigen positive by the Combo test (0/18). Sensitivity of the Combo antigen test was therefore 1.9% (1/52, 95% CI 0.0, 9.9). One false positive Combo antibody result (1/30, 3.3%) was observed in group 4. No false-positive Combo antigen results were observed. The Combo antigen test was positive in group 6 at concentrations of 80 pg/mL, faintly positive at 40 and 20 pg/mL, and negative thereafter. The p24 ELISA antigen test remained positive at 5 pg/mL. Although the antibody component of the Combo test detected antibodies to HIV earlier than the comparison antibody tests used, less than 2% of the cases of antigen-positive HIV infection were detected by the Combo antigen component. The development of a rapid point-of-care test to diagnose acute HIV infection remains an urgent goal.

  10. Characterization of antigens expressed in normal baboon trophoblast and cross-reactive with HIV/SIV antibodies.

    Science.gov (United States)

    Langat, D K; Johnson, P M; Rote, N S; Wango, E O; Owiti, G O; Isahakia, M A; Mwenda, J M

    1999-01-01

    Electron microscopic studies have revealed the presence of endogenous retroviral (ERV) particles in normal primate placental tissues. These particles have ultrastructural similarities to type C retroviral particles and are mainly associated with the trophoblast. In normal human placental tissues, they have antigenic similarity with exogenous retroviruses, such as the human immunodeficiency virus (HIV), and may have a role to play in the regulation of cellular gene expression, syncytiotrophoblast formation or pregnancy-related immunosuppression. In this study, a panel of antibodies (polyclonal and monoclonal antibodies) against viral proteins (anti-HIV and anti-SIV) and endogenous retroviral (ERV) proteins were assessed by immunohistochemistry and immunoblotting, for their cross-reactivity with ERV particles isolated from normal baboon placental tissues. The antibodies (anti-HERV-K RT, anti-ERV3 env, anti-HIV-1 p17, anti-HIV-2 gp120) reacted positively with the syncytiotrophoblast and each antibody recognized one or two proteins of molecular weights (MW) 38, 58 or 64 kDa present in the baboon placental villous tissues and SIV-infected molt-4 Cl8 cells, but not in uninfected cells. The results of this study confirm the specific expression of retroviral cross-reactive antigens in normal baboon placental tissues and suggest placental cellular proteins may have antigenic similarity with those recognized by anti-HIV/SIV antibodies. The role of these retroviral-related proteins expressed at the maternal-fetal interface remain unclear.

  11. HIV-1 Adaptation to Antigen Processing Results in Population-Level Immune Evasion and Affects Subtype Diversification

    DEFF Research Database (Denmark)

    Tenzer, Stefan; Crawford, Hayley; Pymm, Phillip

    2014-01-01

    The recent HIV-1 vaccine failures highlight the need to better understand virus-host interactions. One key question is why CD8(+) T cell responses to two HIV-Gag regions are uniquely associated with delayed disease progression only in patients expressing a few rare HLA class I variants when these...... people vaccinated with natural HIV-1 sequence constructs. Our results suggest that artificial sequence modifications at subtype-specific positions in vitro could refocus and reverse the poor immunogenicity of HIV proteins.......The recent HIV-1 vaccine failures highlight the need to better understand virus-host interactions. One key question is why CD8(+) T cell responses to two HIV-Gag regions are uniquely associated with delayed disease progression only in patients expressing a few rare HLA class I variants when...... these regions encode epitopes presented by ~30 more common HLA variants. By combining epitope processing and computational analyses of the two HIV subtypes responsible for ~60% of worldwide infections, we identified a hitherto unrecognized adaptation to the antigen-processing machinery through substitutions...

  12. Kinetics of Antigen Expression and Epitope Presentation during Virus Infection

    Science.gov (United States)

    Croft, Nathan P.; Smith, Stewart A.; Wong, Yik Chun; Tan, Chor Teck; Dudek, Nadine L.; Flesch, Inge E. A.; Lin, Leon C. W.; Tscharke, David C.; Purcell, Anthony W.

    2013-01-01

    Current knowledge about the dynamics of antigen presentation to T cells during viral infection is very poor despite being of fundamental importance to our understanding of anti-viral immunity. Here we use an advanced mass spectrometry method to simultaneously quantify the presentation of eight vaccinia virus peptide-MHC complexes (epitopes) on infected cells and the amounts of their source antigens at multiple times after infection. The results show a startling 1000-fold range in abundance as well as strikingly different kinetics across the epitopes monitored. The tight correlation between onset of protein expression and epitope display for most antigens provides the strongest support to date that antigen presentation is largely linked to translation and not later degradation of antigens. Finally, we show a complete disconnect between the epitope abundance and immunodominance hierarchy of these eight epitopes. This study highlights the complexity of viral antigen presentation by the host and demonstrates the weakness of simple models that assume total protein levels are directly linked to epitope presentation and immunogenicity. PMID:23382674

  13. 110 HUMAN IMMUNODEFICIENCY VIRUS (HIV) SEROPOSITIVITY ...

    African Journals Online (AJOL)

    INTRODUCTION. An estimated 42 million people worldwide are now infected with the human immunodeficiency virus. (HIV), (1) the causative agent of the acquired immunodeficiency syndrome compared with. 30million people that were infected in 1997(2). Ninety per cent (90%) of these live in developing countries.

  14. Independent clinical significance of HIV antigen determination and CD4 counts in anti-HIV positive patients

    DEFF Research Database (Denmark)

    Skinhøj, P; Hofmann, B; Jacobsen, K D

    1989-01-01

    HIV antigenemia was found in 52/243 HIV antibody positive individuals attending 2 AIDS-screening clinics, giving a prevalence of 13, 25 and 76% in CDC groups II, III and IV, respectively. No correlation was found to decreased CD4 lymphocyte values in the individual groups. HIV antigen therefore...... identified a separate subpopulation. For 138 asymptomatic patients followed prospectively both laboratory parameters predicted HIV-related events, the relative risk factor being 4 for low CD4 value and 6 for presence of HIV antigen. Individuals presenting with HIV antigen and decreased CD4 count all...... developed disease within 18 months, the relative risk factor being 24. Thus the 2 markers, when measured together, effectively separated asymptomatic HIV-infected patients into 1 of 3 risk categories....

  15. 76 FR 58517 - Public Health Service Guideline for Reducing Transmission of Human Immunodeficiency Virus (HIV...

    Science.gov (United States)

    2011-09-21

    ... Transmission of Human Immunodeficiency Virus (HIV), Hepatitis B Virus (HBV), and Hepatitis C Virus (HCV... Guideline for Reducing Transmission of Human Immunodeficiency Virus (HIV), Hepatitis B Virus (HBV), and... Reducing Transmission of Human Immunodeficiency Virus (HIV), Hepatitis B Virus (HBV) and Hepatitis C Virus...

  16. Multiple transmissions of a stable human leucocyte antigen-B27 cytotoxic T-cell-escape strain of HIV-1 in The Netherlands

    NARCIS (Netherlands)

    Cornelissen, Marion; Hoogland, Frederik M.; Back, Nicole Kt; Jurriaans, Suzanne; Zorgdrager, Fokla; Bakker, Margreet; Brinkman, Kees; Prins, Maria; van der Kuyl, Antoinette C.

    2009-01-01

    Objective: The evolution of HIV-1 is largely shaped by the cytotoxic T-cell (CTL) response of the host as encoded by the human leucocyte antigen (HLA) genes. Certain HLA-B alleles can delay disease progression, but it is uncertain whether this protection will sustain or whether the virus is in the

  17. Laboratory Validation of the Sand Fly Fever Virus Antigen Assay

    Science.gov (United States)

    2015-12-01

    stationed there ( Peralta et al. 1965). Rapid field assessments of sand flies for phleboviruses have been previously unavailable. The available tests are...antigenic differ- ences between viral strains ( Peralta et al. 1965, Sather 1970, Srihongse and Johnson 1974, Tesh et al. 1975). We also tested the...illness in Missouri. N Engl J Med 367:834–841. Peralta PH, Shelokov A, Brody JA. 1965. Chagres virus: a new human isolate from Panama. Am J Trop Med

  18. Antigenicity of linear and cyclic peptides mimicking the disulfide loops in HIV-2 envelope glycoprotein: synthesis, reoxidation and purification.

    Science.gov (United States)

    Belhadj Jrad, B; Bahraoui, E

    1998-05-01

    The external envelope glycoprotein (gp125) of human immunodeficiency virus type 2 (HIV-2) contains 22 cysteine residues. The positions of the 11 disulfide bridges in HIV-2 gp125 were determined by analogy with the experimental position of the disulfide bonds found in the gp120 of HIV-1. Peptides expected to mimic all 11 disulfide-bonded domains containing from 13 to 47 amino acids were synthesized by the solid-phase method according to 9-fluorenylmethoxycarbonyl strategy, except for peptide 5, which was assembled according to t-butoxycarbonyl (Boc) strategy. Analysis of all the crude peptides showed that the expected peptides were obtained with good yields, between 75% and 85%. Peptides were purified further by high-performance liquid chromatography (HPLC) on an Aquapore RPC30 C8 column. Peptide homogeneity was more than 90%. For each peptide, linear peptides (L) were SH-iodoacetamidated, whereas cyclization of peptides (C) was performed by air oxidation. Oxidation kinetics was followed with the Ellman test and HPLC. Cyclic peptides were purified by HPLC and characterized by fast atom bombardment mass spectrometry. This analysis showed that a small quantity (peptides (2 and 8) and cyclic peptides containing oxidized methionine or tryptophan residues (4, 9 and 10) were formed. To assess the relevance of conformation for the antigenicity of disulfide-bonded loops of HIV-2 gp125, the antigenicity of linear and cyclic peptides was tested against a set of 76 HIV-2 positive human sera by enzyme-linked immunosorbent assay. Peptides 2, 4 and 9, mimicking the V1, V2 and V3 regions of the external envelope glycoprotein (gp 125) of HIV-2, were the most highly reactive with HIV-2 positive human sera tested at the dilution of 1:50. Cyclic peptides generally were recognized more than linear peptides, as shown by their greater inhibition (2 to 10 times more) of antigen-antibody complexes. Structure-antigenicity of peptide V3, the most reactive peptide (75% of the HIV-2 positive

  19. Antigenic and immunosuppressive properties of a trimeric recombinant transmembrane envelope protein gp41 of HIV-1.

    Directory of Open Access Journals (Sweden)

    Michael Mühle

    Full Text Available The transmembrane envelope (TM protein gp41 of the human immunodeficiency virus-1 (HIV-1 plays an important role during virus infection inducing the fusion of the viral and cellular membranes. In addition, there are indications that the TM protein plays a role in the immunopathogenesis leading to the acquired immunodeficiency syndrome (AIDS. Inactivated virus particles and recombinant gp41 have been reported to inhibit lymphocyte proliferation, as well as to alter cytokine release and gene expression. The same was shown for a peptide corresponding to a highly conserved domain of all retroviral TM proteins, the immunosuppressive domain. Due to its propensity to aggregate and to be expressed at low levels, studies comprising authentic gp41 produced in eukaryotic cells are extremely rare. Here we describe the production of a secreted, soluble recombinant gp41 in 293 cells. The antigen was purified to homogeneity and characterised thoroughly by various biochemical and immunological methods. It was shown that the protein was glycosylated and assembled into trimers. Binding studies by ELISA and surface plasmon resonance using conformation-specific monoclonal antibodies implied a six-helix bundle conformation. The low binding of broadly neutralising antibodies (bnAb directed against the membrane proximal external region (MPER suggested that this gp41 is probably not suited as vaccine to induce such bnAb. Purified gp41 bound to monocytes and to a lesser extent to lymphocytes and triggered the production of specific cytokines when added to normal peripheral blood mononuclear cells. In addition, gp41 expressed on target cells inhibited the antigen-specific response of murine CD8+ T cells by drastically impairing their IFNγ production. To our knowledge, this is the first comprehensive analysis of a gp41 produced in eukaryotic cells including its immunosuppressive properties. Our data provide another line of evidence that gp41 might be directly involved in

  20. Pandemic Influenza A (H1N1) Virus Infection Increases Apoptosis and HIV-1 Replication in HIV-1 Infected Jurkat Cells.

    Science.gov (United States)

    Wang, Xue; Tan, Jiying; Biswas, Santanu; Zhao, Jiangqin; Devadas, Krishnakumar; Ye, Zhiping; Hewlett, Indira

    2016-02-02

    Influenza virus infection has a significant impact on public health, since it is a major cause of morbidity and mortality. It is not well-known whether influenza virus infection affects cell death and human immunodeficiency virus (HIV)-1 replication in HIV-1-infected patients. Using a lymphoma cell line, Jurkat, we examined the in vitro effects of pandemic influenza A (H1N1) virus (pH1N1) infection on cell death and HIV-1 RNA production in infected cells. We found that pH1N1 infection increased apoptotic cell death through Fas and Bax-mediated pathways in HIV-1-infected Jurkat cells. Infection with pH1N1 virus could promote HIV-1 RNA production by activating host transcription factors including nuclear factor kappa-light-chain-enhancer of activated B cells (NF-ĸB), nuclear factor of activated T-cells (NFAT) and activator protein 1 (AP-1) through mitogen-activated protein kinases (MAPK) pathways and T-cell antigen receptor (TCR)-related pathways. The replication of HIV-1 latent infection could be reactivated by pH1N1 infection through TCR and apoptotic pathways. These data indicate that HIV-1 replication can be activated by pH1N1 virus in HIV-1-infected cells resulting in induction of cell death through apoptotic pathways.

  1. ONCOLYTIC VIRUS-MEDIATED REVERSAL OF IMPAIRED TUMOR ANTIGEN PRESENTATION

    Directory of Open Access Journals (Sweden)

    Shashi Ashok Gujar

    2014-04-01

    Full Text Available Anti-tumor immunity can eliminate existing cancer cells and also maintain a constant surveillance against possible relapse. Such an antigen-specific adaptive response begins when tumor-specific T cells become activated. T cell activation requires two signals on antigen presenting cells (APCs: antigen presentation through MHC molecules and co-stimulation. In the absence of one or both of these signals, T cells remain inactivated or can even become tolerized. Cancer cells and their associated microenvironment strategically hinder the processing and presentation of tumor antigens and consequently prevent the development of anti-tumor immunity. Many studies, however, demonstrate that interventions that overturn tumor-associated immune evasion mechanisms can establish anti-tumor immune responses of therapeutic potential. One such intervention is oncolytic virus (OV-based anti-cancer therapy. Here we discuss how OV-induced immunological events override tumor-associated antigen presentation impairment and promote appropriate T cell:APC interaction. Detailed understanding of this phenomenon is pivotal for devising the strategies that will enhance the efficacy of OV-based anti-cancer therapy by complementing its inherent oncolytic

  2. Multicenter evaluation of a new automated fourth-generation human immunodeficiency virus screening assay with a sensitive antigen detection module and high specificity.

    Science.gov (United States)

    Weber, Bernard; Gürtler, Lutz; Thorstensson, Rigmor; Michl, Ulrike; Mühlbacher, Annelies; Bürgisser, Philippe; Villaescusa, Roberto; Eiras, Adolfo; Gabriel, Christian; Stekel, Herbert; Tanprasert, Srivilai; Oota, Sinenaart; Silvestre, Maria-Jose; Marques, Cristina; Ladeira, Maria; Rabenau, Holger; Berger, Annemarie; Schmitt, Urban; Melchior, Walter

    2002-06-01

    Fourth-generation assays for the simultaneous detection of human immunodeficiency virus (HIV) antigen and antibody that were available on the international market until now have antigen detection modules with relatively poor sensitivity and produce a higher rate of false-positive results than third-generation enzyme immunoassays (EIAs). The new Cobas Core HIV Combi EIA with an improved sensitivity for HIV p24 antigen was compared to alternative fourth- and third-generation assays, the p24 antigen test, and HIV type 1 (HIV-1) RNA reverse transcriptase PCR (RT-PCR). A total of 94 seroconversion panels (n = 709 sera), samples from the acute phase of infection after seroconversion (n = 32), anti-HIV-1-positive specimens (n = 730) from patients in different stages of the disease, 462 subtyped samples from different geographical locations, anti-HIV-2-positive sera (n = 302), dilutions of cell culture supernatants (n = 62) from cells infected with different HIV-1 subtypes, selected performance panels from Boston Biomedica Inc., 7,579 unselected samples from blood donors, 303 unselected daily routine samples, 997 specimens from hospitalized patients, and potentially interfering samples (n = 1,222) were tested with Cobas Core HIV Combi EIA. The new assay showed a sensitivity comparable to that of the Abbott HIV-1 AG Monoclonal A for early detection of HIV infection in seroconversion panels. The mean time delay of Cobas Core HIV Combi EIA (last negative sample plus 1 day) in comparison to that for HIV-1 RT-PCR for 87 panels tested with both methods was 2.75 days. The diagnostic window was reduced with Cobas Core HIV Combi EIA by between 3.6 and 5.7 days from that for third-generation assays. The specificities of Cobas Core HIV Combi EIA in blood donors were 99.84 and 99.85% (after repeated testing). Overall, 30 repeatedly reactive false-positive results out of 10,031 HIV-negative samples were obtained with Cobas Core HIV Combi EIA. Our results show that a fourth

  3. Frequency of Hepatitis B Virus, Hepatitis C Virus and HIV Infections in Cannabis and Opioid Addicts

    Directory of Open Access Journals (Sweden)

    Nuran KARABULUT

    2017-04-01

    Full Text Available Objective: There are very few data about the epidemiology of hepatitis B virus (HBV, hepatitis C virus (HCV and HIV infections in drug addicts in Turkey, whereas several countries have a developed surveillance systems to monitor the spread of HBV, HCV and HIV infections in drug users. In this study, HBV, HCV and HIV prevalence in cannabis and opioid addicts were investigated. Materials and Methods: Hepatitis B surface antigen (HBsAg, anti-HBs, anti-HCV and anti-HIV tests were analyzed by enzyme-linked immunosorbent assay. The cannabis and opioid metabolites in urine samples of drug addicts were analyzed by cloned enzyme donor immunoassay. Results: This retrospective study was conducted on 276 individuals with a mean age of 28.89±10.49 years. HBsAg, anti-HBs and anti-HCV prevalence in drug addicts was found to be 4%, 52.3% and 7.9%, respectively. In all the drug addicts, anti-HIV test was negative. Whereas the rate of HBsAg among cannabis users (8.8% was higher than opioid (4.1% and both cannabis and opioid users (1.4%, the difference was not statistically significant. Although anti-HCV positivity among cannabis users was not detected, 6.4% of opioid users and 15.9% of both cannabis and opioid users were anti-HCV positive (p=0.009. Conclusion: This study showed that HCV infection among especially opioid users and both cannabis and opioid users was a problem. Understanding of local status in HBV, HCV and HIV infections is crucial for developing prevention and geographical strategies for these infections.

  4. Survival of human immunodeficiency virus (HIV), HIV-infected lymphocytes, and poliovirus in water.

    OpenAIRE

    Moore, B E

    1993-01-01

    The potential for human immunodeficiency virus (HIV) to enter domestic sewers via contaminated body fluids such as blood has spurred interest in the survival of this virus in water and wastewater. This study focused on establishing the inactivation of HIV and productively infected lymphocytes in dechlorinated tap water. In addition, HIV survival was compared with that of poliovirus. Results indicated that either free HIV or cell-associated HIV was rapidly inactivated, with a 90% loss of infec...

  5. Impact of tuberculosis treatment on CD4 cell count, HIV RNA, and p24 antigen in patients with HIV and tuberculosis

    DEFF Research Database (Denmark)

    Wejse, Christian; Furtado, A.; Camara, C.

    2013-01-01

    To describe HIV RNA levels during tuberculosis (TB) infection in patients co-infected with TB and HIV. Moreover, to examine the p24 antigen profile during TB treatment.......To describe HIV RNA levels during tuberculosis (TB) infection in patients co-infected with TB and HIV. Moreover, to examine the p24 antigen profile during TB treatment....

  6. Presence of p24-Antigen Associated to Erythrocyte in HIV-Positive Individuals Even in Patients with Undetectable Plasma Viral Load

    Science.gov (United States)

    Garcia, Maria Noé; dos Ramos Farias, Maria Sol; Ávila, Maria Mercedes; Rabinovich, Roberto Daniel

    2011-01-01

    Background HIV adherence to erythrocytes has been demonstrated in vitro, and it has been suggested that erythrocytes may be carriers of the virus. However, the association between HIV particles or viral proteins and erythrocytes in HIV-infected individuals is still to be elucidated. Methodology/Principal Findings HIV-positive participants (n = 112) were classified into two groups according to values of three plasma viral loads (pVL) determined during the 12-month period prior to the study. The first group included 71 individuals with detectable pVL, whereas the second group included 41 individuals with undetectable pVL. Plasma viral load, erythrocyte-associated p24-antigen and p24-antigen in plasma were determined at the moment of the study. A total of 51 out of the 71 patients with detectable pVL showed erythrocyte-associated p24-antigen whereas 13 showed p24-antigen in plasma. Twenty-two out of the 51 patients with erythrocyte-associated p24-antigen showed pVLerythrocyte-associated p24-antigen was not related to p24-antigen in plasma or pVL levels in this group. Among the 41 patients with prior undetectable pVL, eight presented detectable pVL and erythrocyte-associated p24-antigen at the moment of the study. The other 33 showed undetectable pVL and five of these presented erythrocyte-associated p24-antigen. A positive relationship was found between the presence of erythrocyte-associated p24-antigen and the detectable pVL at the moment of the study (perythrocytes was determined and it was always accompanied by erythrocyte-associated p24-antigen detection. Conclusions/Significance This study demonstrates the presence of erythrocyte-associated p24-antigen in HIV-infected individuals. Since erythrocyte-associated p24-antigen is not always related to pVL or p24-antigen in plasma, erythrocyte-associated p24-antigen showed viral expression not represented in plasma. Therefore, the determination of erythrocyte-associated p24-antigen may contribute to better

  7. Influence of human leukocyte antigen-B22 alleles on the course of human immunodeficiency virus type 1 infection in 3 cohorts of white men

    NARCIS (Netherlands)

    Dorak, M. Tevfik; Tang, Jianming; Tang, Shenghui; Penman-Aguilar, Ana; Coutinho, Roel A.; Goedert, James J.; Detels, Roger; Kaslow, Richard A.

    2003-01-01

    The human leukocyte antigen (HLA)-B22 serogroup--which consists of the alleles B*54, B*55, and B*56--has been associated with rapidly progressive disease in white patients with human immunodeficiency virus (HIV) infection. Subjects from 3 cohorts of men who have sex with men (N=671), all of whom

  8. Hepatitis B virus antigens impair NK cell function.

    Science.gov (United States)

    Yang, Yinli; Han, Qiuju; Zhang, Cai; Xiao, Min; Zhang, Jian

    2016-09-01

    An inadequate immune response of the host is thought to be a critical factor causing chronic hepatitis B virus (CHB) infection. Natural killer (NK) cells, as one of the key players in the eradication and control of viral infections, were functionally impaired in CHB patients, which might contribute to viral persistence. Here, we reported that HBV antigens HBsAg and HBeAg directly inhibited NK cell function. HBsAg and/or HBeAg blocked NK cell activation, cytokine production and cytotoxic granule release in human NK cell-line NK-92 cells, which might be related to the downregulation of activating receptors and upregulation of inhibitory receptor. Furthermore, the underlying mechanisms likely involved the suppression of STAT1, NF-κB and p38 MAPK pathways. These findings implicated that HBV antigen-mediated inhibition of NK cells might be an efficient strategy for HBV evasion, targeting the early antiviral responses mediated by NK cells and resulting in the establishment of chronic virus infection. Therefore, this study revealed the relationship between viral antigens and human immune function, especially a potential important interaction between HBV and innate immune responses. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. War and peace between microbes: HIV-1 interactions with coinfecting viruses.

    Science.gov (United States)

    Lisco, Andrea; Vanpouille, Christophe; Margolis, Leonid

    2009-11-19

    HIV-1 disrupts the homeostatic equilibrium between the host and coinfecting microbes, facilitating reactivation of persistent viruses and invasion by new viruses. These viruses usually accelerate HIV disease but occasionally create conditions detrimental for HIV-1. Understanding these phenomena may lead to anti-HIV-1 strategies that specifically target interactions between HIV-1 and coinfecting viruses.

  10. Preserved MHC class II antigen processing in monocytes from HIV-infected individuals.

    Directory of Open Access Journals (Sweden)

    Laila Woc-Colburn

    2010-03-01

    Full Text Available MHC-II restricted CD4+ T cells are dependent on antigen presenting cells (APC for their activation. APC dysfunction in HIV-infected individuals could accelerate or exacerbate CD4+ T cell dysfunction and may contribute to increased levels of immunodeficiency seen in some patients regardless of their CD4+ T cell numbers. Here we test the hypothesis that APC from HIV-infected individuals have diminished antigen processing and presentation capacity.Monocytes (MN were purified by immuno-magnetic bead isolation techniques from HLA-DR1.01+ or DR15.01+ HIV-infected and uninfected individuals. MN were analyzed for surface MHC-II expression and for antigen processing and presentation capacity after overnight incubation with soluble antigen or peptide and HLA-DR matched T cell hybridomas. Surface expression of HLA-DR was 20% reduced (p<0.03 on MN from HIV-infected individuals. In spite of this, there was no significant difference in antigen processing and presentation by MN from 14 HIV-infected donors (8 HLA-DR1.01+ and 6 HLA-DR15.01+ compared to 24 HIV-uninfected HLA-matched subjects.We demonstrated that MHC class II antigen processing and presentation is preserved in MN from HIV-infected individuals. This further supports the concept that this aspect of APC function does not further contribute to CD4+ T cell dysfunction in HIV disease.

  11. Frequent hepatitis B virus rebound among HIV-hepatitis B virus-coinfected patients following antiretroviral therapy interruption

    DEFF Research Database (Denmark)

    Dore, Gregory J; Soriano, Vicente; Rockstroh, Jürgen

    2010-01-01

    BACKGROUND: The impact of antiretroviral therapy (ART) interruption in HIV-hepatitis B virus (HBV)-coinfected patients was examined in the Strategic Management of AntiRetroviral Therapy (SMART) study. METHODS: Plasma HBV DNA was measured in all hepatitis B surface antigen-positive (HBV.......0002), nondetectable HBV DNA at baseline (P = 0.007), and black race (P = 0.03). Time to ART reinitiation was shorter (7.5, 15.6, and 17.8 months; P hepatitis C virus-positive and non-HBV/hepatitis...... C virus participants in the drug conservation arm. No hepatic decompensation events occurred among HBV-positive participants in either arm. CONCLUSION: HBV DNA rebound following ART interruption is common and may be associated with accelerated immune deficiency in HIV-HBV-coinfected patients....

  12. The Zika virus envelope protein glycan loop regulates virion antigenicity.

    Science.gov (United States)

    Goo, Leslie; DeMaso, Christina R; Pelc, Rebecca S; Ledgerwood, Julie E; Graham, Barney S; Kuhn, Richard J; Pierson, Theodore C

    2018-01-02

    Because antibodies are an important component of flavivirus immunity, understanding the antigenic structure of flaviviruses is critical. Compared to dengue virus (DENV), the loop containing the single N-linked glycosylation site on Zika virus (ZIKV) envelope (E) proteins extends further towards the DII fusion loop (DII-FL) on neighboring E proteins within E dimers on mature viruses. Although ZIKV is poorly neutralized by DII-FL antibodies, we demonstrated significantly increased neutralization sensitivity of ZIKV particles incorporating the DENV glycan loop. Increased neutralization sensitivity was independent of E protein glycosylation: ZIKV lacking E protein glycans remained poorly neutralized, whereas ZIKV loop chimeras with or without an E protein glycan were potently neutralized. ZIKV particles lacking the E protein glycan were capable of infecting Raji cells expressing the lectin DC-SIGNR, suggesting the prM glycan of partially mature particles can facilitate entry. Our study provides insight into the determinants of ZIKV E protein function and antigenicity. Copyright © 2017. Published by Elsevier Inc.

  13. Two types of nanoparticle-based bio-barcode amplification assays to detect HIV-1 p24 antigen

    Directory of Open Access Journals (Sweden)

    Dong Huahuang

    2012-08-01

    Full Text Available Abstract Background HIV-1 p24 antigen is a major viral component of human immunodeficiency virus type 1 (HIV-1 which can be used to identify persons in the early stage of infection and transmission of HIV-1 from infected mothers to infants. The detection of p24 is usually accomplished by using an enzyme-linked immunosorbent assay (ELISA with low detection sensitivity. Here we report the use of two bio-barcode amplification (BCA assays combined with polymerase chain reaction (PCR and gel electrophoresis to quantify HIV-1 p24 antigen. Method A pair of anti-p24 monoclonal antibodies (mAbs were used in BCA assays to capture HIV-1 p24 antigen in a sandwich format and allowed for the quantitative measurement of captured p24 using PCR and gel electrophoresis. The first 1 G12 mAb was coated on microplate wells or magnetic microparticles (MMPs to capture free p24 antigens. Captured p24 in turn captured 1D4 mAb coated gold nanoparticle probes (GNPs containing double-stranded DNA oligonucleotides. One strand of the oligonucleotides was covalently immobilized whereas the unbound complimentary bio-barcode DNA strand could be released upon heating. The released bio-barcode DNA was amplified by PCR, electrophoresed in agarose gel and quantified. Results The in-house ELISA assay was found to quantify p24 antigen with a limit of detection (LOD of 1,000 pg/ml and a linear range between 3,000 and 100,000 pg/ml. In contrast, the BCA-based microplate method yielded an LOD of 1 pg/ml and a linear detection range from 1 to 10,000 pg/ml. The BCA-based MMP method yielded an LOD of 0.1 pg/ml and a linear detection range from 0.1 to 1,000 pg/ml. Conclusions When combined with PCR and simple gel electrophoresis, BCA-based microplate and MMPs assays can be used to quantify HIV-1 p24 antigen. These methods are 3–4 orders of magnitude more sensitive than our in-house ELISA-based assay and may provide a useful approach to detect p24 in patients newly infected

  14. Preparation of purified bluetongue virus group antigen for use as a diagnostic reagent

    Energy Technology Data Exchange (ETDEWEB)

    Gumm, I.D.; Newman, J.F.E. (Animal Virus Research Inst., Pirbright (UK); Rhodes Univ., Grahamstown (South Africa))

    1982-01-01

    Soluble group antigen isolated from bluetongue virus infected BHK cells has been shown to be a single protein with a molecular weight of 38,000 and to comigrate on polyacrylamide gels with protein 7 isolated from virus particles. Purification by exclusion chromatography and isoelectric focussing yields a protein that appears to be antigenically idential to the native group antigen found in virus harvests; it is non infectious for sheep and is thought to be largely free from host cell and other virus specified proteins. It is suggested that this antigen could be used in diagnostic procedures with safety.

  15. Prevalence of human immunodeficiency virus, hepatitis C virus, hepatitis B virus and syphilis among individuals attending anonymous testing for HIV in Luanda, Angola.

    Science.gov (United States)

    Guimarães Nebenzahl, H; Lopes, A; Castro, R; Pereira, F

    2013-01-24

    Human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV) and syphilis remain major infections around the world. In Angola there are about 166 000 individuals living with HIV, representing a prevalence of 1.98% in adults between 15 and 49 years of age. In a 2003 study in Luanda, 4.5% of pregnant women had antibodies to HIV and 8.1% to HBV, and 5.4% were infected with Treponema pallidum. Objectives. The aim of this study was to determine the prevalence of HIV-1 and 2, HBV, HCV and T. pallidum serological markers, and hence the prevalence of these infections, in individuals attending a sexually transmitted disease clinic in Luanda, Angola, and the burden of these infections in the Angolan population. Methods. Individuals attending a centre for anonymous testing for HIV were randomly included in the study. All samples were tested for HBV surface antigen (HBsAg), anti-HCV and anti-HIV-1 and 2 antibodies and antibodies to T. pallidum. Results. A total of 431 individuals (262 women and 169 men) were studied, of whom 10.0% (43/431) were seropositive for T. pallidum and 4.6% had active syphilis; 8.8% (38/431) were seropositive for HIV-1 and/or HIV-2 (of these, 78.9% were HIV-1-positive, 2.6% HIV-2-positive and 18.4% co-infected); 9.3% (40/431) were HBsAg-positive, while 8.1% (35/431) had antibodies to HCV. Of 102 patients with positive results, 26 (25.5%, or 6.0% of the total of 431 patients) were positive for more than one of the organisms studied. Rates of co-infection were as follows: 2.3% (10/431) for HIV/HBV, 0.9% (4/431) for HIV/HCV, and 0.9% (4/431) for HCV/HBV. Three individuals with active syphilis had viral co-infection, hepatitis B in 1 case and HIV in 2. Five individuals (1.2% of the total) were seropositive for three infections, HIV, hepatitis B and hepatitis C in 3 cases and HIV, hepatitis C and syphilis in 2. Conclusions. A high prevalence of co-infection with the infections studied was found in this population, including HIV

  16. Live attenuated rubella vectors expressing SIV and HIV vaccine antigens replicate and elicit durable immune responses in rhesus macaques

    Science.gov (United States)

    2013-01-01

    Background Live attenuated viruses are among our most potent and effective vaccines. For human immunodeficiency virus, however, a live attenuated strain could present substantial safety concerns. We have used the live attenuated rubella vaccine strain RA27/3 as a vector to express SIV and HIV vaccine antigens because its safety and immunogenicity have been demonstrated in millions of children. One dose protects for life against rubella infection. In previous studies, rubella vectors replicated to high titers in cell culture while stably expressing SIV and HIV antigens. Their viability in vivo, however, as well as immunogenicity and antibody persistence, were unknown. Results This paper reports the first successful trial of rubella vectors in rhesus macaques, in combination with DNA vaccines in a prime and boost strategy. The vectors grew robustly in vivo, and the protein inserts were highly immunogenic. Antibody titers elicited by the SIV Gag vector were greater than or equal to those elicited by natural SIV infection. The antibodies were long lasting, and they were boosted by a second dose of replication-competent rubella vectors given six months later, indicating the induction of memory B cells. Conclusions Rubella vectors can serve as a vaccine platform for safe delivery and expression of SIV and HIV antigens. By presenting these antigens in the context of an acute infection, at a high level and for a prolonged duration, these vectors can stimulate a strong and persistent immune response, including maturation of memory B cells. Rhesus macaques will provide an ideal animal model for demonstrating immunogenicity of novel vectors and protection against SIV or SHIV challenge. PMID:24041113

  17. Antigenic and genetic characterization of rabies virus isolates from Uruguay.

    Science.gov (United States)

    Guarino, Helena; Castilho, Juliana Galera; Souto, Juanita; Oliveira, Rafael de Novaes; Carrieri, Maria Luiza; Kotait, Ivanete

    2013-05-01

    After 25 years without any reported cases of rabies in Uruguay, the northern region of the country experienced an epizootic of bovine paralytic rabies in October 2007. The outbreak affected bovines and equines, and the main source of infection was the bat Desmodus rotundus, the only hematophagous species in the country. From October 2007 to July 2008, 42 bovine, 3 equine and 120 chiropteran samples were submitted to the National Veterinary Diagnostic Laboratory for rabies testing. A total of 12 samples (7 bovine, 2 equine and 3 from D. rotundus) were positive by the fluorescent antibody test, and viruses were isolated by the mouse inoculation test. The objective of this study was to compare the antigenic and genetic characteristics of these isolates and three isolates from insectivorous bats from other regions. Antigenic typing using a panel of eight monoclonal antibodies identified all 12 viruses as variant 3 (AgV3), a variant associated with D. rotundus. Two isolates from insectivorous bats (Tadarida brasiliensis and Molossus sp.) were characterized as antigenic variant 4 (AgV4) while the third, from Myotis sp., could not be characterized using this panel as its reactivity pattern did not match that of any of the known antigenic variants. Partial N-gene sequences (nt 149-1420) of these isolates were aligned with homologous sequences derived from GenBank by the CLUSTAL/W method and used to build a neighbor-joining distance tree with the Kimura 2-parameter model. All 12 isolates were genetically grouped into the D. rotundus cluster as they shared 100% identity. In the phylogenetic analysis, the three isolates from insectivorous bats segregated into three clusters: one related to T. brasiliensis, one to Myotis sp. and the other to Lasiurus sp., although the isolate associated with the latter came from a Molossus sp. specimen. These results indicate that AgV3 was associated with the outbreak of bovine paralytic rabies in Uruguay. This is the first report of rabies

  18. Serological profiles of Herpes simplex virus type 2 among HIV ...

    African Journals Online (AJOL)

    Herpes simplex virus type-2 (HSV-2) is the major cause of genital ulcer diseases (GUD) consequently a significant factor for the acquisition and transmission of human immunodeficiency virus (HIV). Despite its importance there is paucity of data regarding the magnitude of HSV-2 in non-HIV infected population in ...

  19. Influence of HIV and HCV on T cell antigen presentation and challenges in the development of vaccines.

    Science.gov (United States)

    John, Mina; Gaudieri, Silvana

    2014-01-01

    Some of the central challenges for developing effective vaccines against HIV and hepatitis C virus (HCV) are similar. Both infections are caused by small, highly mutable, rapidly replicating RNA viruses with the ability to establish long-term chronic pathogenic infection in human hosts. HIV has caused 60 million infections globally and HCV 180 million and both viruses may co-exist among certain populations by virtue of common blood-borne, sexual, or vertical transmission. Persistence of both pathogens is achieved by evasion of intrinsic, innate, and adaptive immune defenses but with some distinct mechanisms reflecting their differences in evolutionary history, replication characteristics, cell tropism, and visibility to mucosal versus systemic and hepatic immune responses. A potent and durable antibody and T cell response is a likely requirement of future HIV and HCV vaccines. Perhaps the single biggest difference between the two vaccine design challenges is that in HCV, a natural model of protective immunity can be found in those who resolve acute infection spontaneously. Such spontaneous resolvers exhibit durable and functional CD4(+) and CD8(+) T cell responses (Diepolder et al., 1995; Cooper et al., 1999; Thimme et al., 2001; Grakoui et al., 2003; Lauer et al., 2004; Schulze Zur Wiesch et al., 2012). However, frequent re-infection suggests partial or lack of protective immunity against heterologous HCV strains, possibly indicative of the degree of genetic diversity of circulating HCV genotypes and subtypes. There is no natural model of protective immunity in HIV, however, studies of "elite controllers," or individuals who have durably suppressed levels of plasma HIV RNA without antiretroviral therapy, has provided the strongest evidence for CD8(+) T cell responses in controlling viremia and limiting reservoir burden in established infection. Here we compare and contrast the specific mechanisms of immune evasion used by HIV and HCV, which subvert adaptive human

  20. Human bite and human immune deficiency virus (HIV) transmission ...

    African Journals Online (AJOL)

    Background: The concentration of human immune deficiency virus (HIV) in the saliva of a carrier is low. As a result, human bite is not considered the traditional route of HIV infection transmission. Aim: To report a case of HIV sero-positivity following a human bite. Setting: University of Port Harcourt Teaching Hospital, Port ...

  1. Prevalence of human immunodeficiency virus (HIV) infection among ...

    African Journals Online (AJOL)

    Prevalence of human immunodeficiency virus (HIV) infection among pregnant women in an antenatal clinic in Port-Harcourt, Nigeria. ... 6, No 3 (2007) >. Log in or Register to get access to full text downloads. ... A total of 10,032 pregnant women were screened for the possible occurrence of HIV 1 and HIV 2 within the period.

  2. High prevalence of HIV-1 CRF01_AE viruses among female commercial sex workers residing in Surabaya, Indonesia.

    Directory of Open Access Journals (Sweden)

    Tomohiro Kotaki

    Full Text Available BACKGROUND: Human immunodeficiency virus (HIV infection and acquired immune deficiency syndrome (AIDS cause serious health problems and have an impact on the Indonesian economy. In addition, the rapid epidemic growth of HIV is continuing in Indonesia. Commercial sex plays a significant role in the spread of HIV; therefore, in order to reveal the current HIV prevalence rate among commercial sex workers (CSWs, we conducted an epidemiological study on HIV infection among CSWs residing in Surabaya, the capital of East Java province of Indonesia with large communities of CSWs. METHODOLOGY/PRINCIPAL FINDINGS: The prevalence of HIV infection among 200 CSWs was studied. In addition, the subtype of HIV type 1 (HIV-1 and the prevalence of other blood-borne viruses, hepatitis B virus (HBV, hepatitis C virus (HCV and GB virus C (GBV-C, were studied. The prevalence rates of HIV, hepatitis B core antibody, hepatitis B surface antigen, anti-HCV antibodies and anti-GBV-C antibodies were 11%, 64%, 4%, 0.5% and 0% among CSWs involved in this study, respectively. HIV-1 CRF01_AE viral gene fragments were detected in most HIV-positive samples. In addition, most CSWs showed low awareness of sexually transmitted diseases and had unprotected sex with their clients. CONCLUSIONS/SIGNIFICANCE: The HIV prevalence rate among CSWs was significantly higher than that among the general population in Indonesia (0.2-0.4%. In addition, CSWs were at a high risk of exposure to HBV, although chronic HBV infection was less frequently established. Our results suggest the necessity of efficient prevention programs for HIV and other blood-borne viral infections among CSWs in Surabaya, Indonesia.

  3. Seroepidemiology of hepatitis A, hepatitis B and varicella virus in people living with HIV in Ireland.

    Science.gov (United States)

    Sadlier, Corinna; O'Rourke, Anna; Carr, Alison; Bergin, Colm

    Epidemiological studies investigating seroprevalence of vaccine preventable infections at both individual and population level are important in guiding screening and vaccination practices. Data on seroprevalence of common vaccine preventable infections in HIV-infected individuals is lacking. We carried out a retrospective cohort study to investigate serological immunity and factors associated with immunity to hepatitis A virus (HAV), hepatitis B virus (HBV) and varicalla virus (VZV) in a cohort of HIV-infected individuals attending a large ambulatory HIV specialist centre in Ireland. Basic demographic data including risk of acquisition of HIV and region of origin was recorded. Between-group prevalence was compared using the Chi2 test and Wilkoxin signed rank test. Univariate variables with phepatitis A IgG positive, 94% were VZV IgG positive, 3% were HBV surface antigen (sAg) positive while 29% were HBV core antibody (cAb) positive. This study identifies a significant proportion of HIV infected who were susceptible to common vaccine preventable infections. These results highlight the importance of proactive screening and immunization of HIV-infected individuals to ensure optimal protect ionagainst vaccine preventable diseases in this at risk patient group. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Pelacakan Secara Imunohistokimiawi Antigen Virus pada Ayam yang Diinfeksi dengan Virus Penyakit Tetelo (IMMUNOHISTOCHEMICAL DETECTION OF VIRAL ANTIGEN IN TISSUE OF CHICKENS EXPERIMENTALLY INFECTED WITH NEWCASTLE DISEASE VIRUS

    Directory of Open Access Journals (Sweden)

    Anak Agung Ayu Mirah Adi

    2013-07-01

    Full Text Available In order to study the distribution of Newcastle disease virus (NDV following infection, chickenswere experimentally infected with visceretropic velogenic NDV isolate. Monoclonal antibodies (mAbsagainst the NDV LaSota vaccine strain were then produced to detect viral antigen in the infectedorgans. The mAbs were firstly tested for their specificity by enzyme linked immunosorbent assay(ELISA using NDV and normal allantoic fluids as antigens. Eight mAbs specific against NDVwere isolated and two mAbs were used for immunodetection of NDV antigen in chicken’s tissues.By immunohistochemistry labeled streptavidin-biotin (LSAB staining NDV–antigen was detectedin paraffin embedded tissues of NDV-infected chickens. NDV antigen was not detected in noninfected chickens. In the infected chickens, high intensity of NDV antigen was detected in thelymphoid tissues, lung and intestine. The NDV antigen with a lesser intensity was detected in thebrain, trachea, liver and myocardium. This study shows that although viscerotropic velogenicNDV isolate can infect almost all organs, the main target of infection are lung, intestine andlymphoids tissues

  5. Viral gene expression, antibody production and immune complex formation in human immunodeficiency virus infection

    NARCIS (Netherlands)

    Lange, J. M.; Paul, D. A.; de Wolf, F.; Coutinho, R. A.; Goudsmit, J.

    1987-01-01

    Human immunodeficiency virus (HIV) antigen (HIV-Ag) in polyethylene glycol (PEG) precipitates and supernatants and HIV antibodies (HIV-Ab) to core and envelope antigens were studied in serial serum samples of three HIV-Ab seroconverters and 11 HIV-Ab seropositive men with a mean follow-up time of

  6. Genetic versus antigenic differences among highly pathogenic H5N1 avian influenza A viruses

    NARCIS (Netherlands)

    Peeters, Ben; Reemers, Sylvia; Dortmans, Jos; Vries, de Erik; Jong, de Mart; Zande, van de Saskia; Rottier, Peter J.M.; Haan, de Cornelis A.M.

    2017-01-01

    Highly pathogenic H5N1 avian influenza A viruses display a remarkable genetic and antigenic diversity. We examined to what extent genetic distances between several H5N1 viruses from different clades correlate with antigenic differences and vaccine performance. H5-specific antisera were generated,

  7. Acute HIV-1 Infection in Antigen/Antibody-negative Blood Donors in ...

    African Journals Online (AJOL)

    The aim of this study was to determine the prevalence of acute HIV infection among HIV antigen/antibody negative blood donors. This was a cross-sectional blood donation based facility study conducted at Eastern Zone Blood Transfusion Services in Dar es Salaam from December 2009 to April 2010. Apparently healthy ...

  8. Prevalence and determinants of antibodies to hepatitis C virus and markers for hepatitis B virus infection in patients with HIV infection in Aquitaine. Groupe d'Epidémiologie Clinique du SIDA en Aquitaine.

    Science.gov (United States)

    Saillour, F.; Dabis, F.; Dupon, M.; Lacoste, D.; Trimoulet, P.; Rispal, P.; Monlun, E.; Ragnaud, J. M.; Morlat, P.; Pellegrin, J. L.; Fleury, H.; Couzigou, P.

    1996-01-01

    OBJECTIVE: To evaluate the prevalence of antibodies to hepatitis C virus and serological markers for hepatitis B virus infection in patients with HIV. DESIGN: Cross sectional survey. SETTING: Aquitaine, southwestern France, 1991-94. SUBJECTS: 1935 HIV positive patients seen at least once since June 1991. MAIN OUTCOME MEASURES: Presence of antibodies to hepatitis C virus were detected by second or third generation enzyme linked immunosorbent assay (ELISA) and recombinant immunoblot assay (RIBA) and markers for hepatitis B virus detected by ELISA. RESULTS: The prevalence was 42.5% (823) for antibodies to hepatitis C virus, 56.4 (507) for antibodies to hepatitis B core antigen, 6.9% (133) for hepatitis B surface antigen, 30.2% (584) for antibodies to hepatitis B core and surface antigen with no detectable surface antigen, 26.2% (507) for antibodies to core antigen only, and 4.8% (92) for antibodies to surface antigen only. The prevalence of antibodies to hepatitis C virus was 86.1% (726/843) in subjects who had bloodborne HIV infection and 7.3% (66/899) in those with sexually acquired infection. The prevalence of markers for hepatitis B was higher among homosexuals than in the other groups of patients, except for antibodies to surface antigen alone. The relation between markers for hepatitis B and hepatitis C virus was negative among men but positive among women. CONCLUSIONS: The results favour the hypothesis that hepatitis C virus is sexually transmitted much less commonly than either HIV or hepatitis B virus. PMID:8776313

  9. Evaluating the Use of Commercial West Nile Virus Antigens as Positive Controls in the Rapid Analyte Measurement Platform West Nile Virus Assay.

    Science.gov (United States)

    Burkhalter, Kristen L; Savage, Harry M

    2015-12-01

    We evaluated the utility of 2 types of commercially available antigens as positive controls in the Rapid Analyte Measurement Platform (RAMP®) West Nile virus (WNV) assay. Purified recombinant WNV envelope antigens and whole killed virus antigens produced positive RAMP results and either type would be useful as a positive control. Killed virus antigens provide operational and economic advantages and we recommend their use over purified recombinant antigens. We also offer practical applications for RAMP positive controls and recommendations for preparing them.

  10. Performances of fourth generation HIV antigen/antibody assays on filter paper for detection of early HIV infections.

    Science.gov (United States)

    Kania, Dramane; Truong, Tam Nguyen; Montoya, Ana; Nagot, Nicolas; Van de Perre, Philippe; Tuaillon, Edouard

    2015-01-01

    Point-of-care testing and diagnosis of HIV acute infections play important roles in preventing transmission, but HIV rapid diagnosis tests have poor capacity to detect early infections. Filter paper can be used for capillary blood collection and HIV testing using 4th generation immunoassays. Antigen/antibody combined immunoassays were evaluated for their capacity to identify early HIV infections using filter paper in comparison with rapid test. Thirty nine serum samples collected from HIV seroconverters were spotted onto filter paper and tested by the Roche Elecsys(®) HIV Combi PT test and the DiaSorin Liaison XL Murex HIV Ab/Ag assay. Fourth generation immunoassays identified 34 out of 39 HIV early infections using dried serum spot, whereas the Determine™ HIV-1/2 rapid test detected 24 out of 39 HIV positive serum (87.2% vs 61.5% respectively, p = 0.009). p24 antigen was detected by the Liaison XL in 19 dried serum samples (48.7%). In the group characterized by a negative western blot, 7 out of 8 (87.5%) and 6 out of 8 (75.0%) samples were found positive for HIV using the Elecsys and the Liaison XL, respectively. None of these eight samples classified in this group of early acute infections were found positive by the rapid test. Fourth generation Ag/Ab immunoassays performed on dried serum spot had good performance for HIV testing during the early phases of HIV infection. This method may be useful to detect HIV early infections in hard-to-reach populations and individuals living in remote areas before rapid tests become positive. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Phosphorylation of the Epstein-Barr virus nuclear antigen 2

    DEFF Research Database (Denmark)

    Grässer, F A; Göttel, S; Haiss, P

    1992-01-01

    A major in vivo phosphorylation site of the Epstein-Barr virus nuclear antigen 2 (EBNA-2) was found to be localized at the C-terminus of the protein. In vitro phosphorylation studies using casein kinase 1 (CK-1) and casein kinase 2 (CK-2) revealed that EBNA-2 is a substrate for CK-2, but not for CK......-1. The CK-2 specific phosphorylation site was localized in the 140 C-terminal amino acids using a recombinant trpE-C-terminal fusion protein. In a similar experiment, the 58 N-terminal amino acids expressed as a recombinant trpE-fusion protein were not phosphorylated. Phosphorylation of a synthetic...

  12. Aguacate virus, a new antigenic complex of the genus Phlebovirus (family Bunyaviridae).

    Science.gov (United States)

    Palacios, Gustavo; da Rosa, Amelia Travassos; Savji, Nazir; Sze, Wilson; Wick, Ivan; Guzman, Hilda; Hutchison, Stephen; Tesh, Robert; Lipkin, W Ian

    2011-06-01

    Genomic and antigenic characterization of Aguacate virus, a tentative species of the genus Phlebovirus, and three other unclassified viruses, Armero virus, Durania virus and Ixcanal virus, demonstrate a close relationship to one another. They are distinct from the other nine recognized species within the genus Phlebovirus. We propose to designate them as a new (tenth) serogroup or species (Aguacate virus) within the genus. The four viruses were all isolated from phlebotomine sandflies (Lutzomyia sp.) collected in Central and South America. Aguacate virus appears to be a natural reassortant and serves as one more example of the high frequency of reassortment in this genus.

  13. Update on human immunodeficiency virus (HIV)-2 infection.

    Science.gov (United States)

    Campbell-Yesufu, Omobolaji T; Gandhi, Rajesh T

    2011-03-15

    Infection with human immunodeficiency virus type 2 (HIV-2) occurs mainly in West Africa, but an increasing number of cases have been recognized in Europe, India, and the United States. In this era of global integration, clinicians must be aware of when to consider the diagnosis of HIV-2 infection and how to test for this virus. Although there is debate regarding when therapy should be initiated and which regimen should be chosen, recent trials have provided important information on treatment options for HIV-2 infection. In this review, we present information on recent clinical advances in our understanding of HIV-2 infection and highlight remaining diagnostic and therapeutic challenges.

  14. Performance characteristics of a combined hepatitis C virus core antigen and anti–hepatitis C virus antibody test in different patient groups

    Directory of Open Access Journals (Sweden)

    Jeng-Fu Yang

    2011-07-01

    Full Text Available We evaluated the performance of a hepatitis C virus (HCV antigen/antibody combination test [Murex HCV Antigen/Antibody Combination Test (Murex Ag/Ab test] by comparing it with the current third-generation HCV antibody enzyme immunoassay (anti-HCV. A total of 403 serum samples were consecutively collected from four patient groups: healthy controls (n=100; HCV-infected patients (HCV group, n=102; Human immunodeficiency virus (HIV/HCV-infected patients (HIV/HCV group, n=100; and patients with uremia (uremia group, n=101. Performances were evaluated for the Murex Ag/Ab, anti-HCV, and HCV RNA in the HIV/HCV and uremia patient groups. In the HCV group, all 102 samples showed concordant positive and negative results for anti-HCV, Murex Ag/Ab, and HCV RNA tests. In the HIV/HCV group, all 100 samples were positive for both anti-HCV and Murex Ag/Ab tests, whereas 88 patients (88% were HCV RNA positive. In the uremia group, 14 (69.0% of the 23 anti-HCV-positive patients were HCV RNA positive, whereas 14 (77.8% of the 18 Murex Ag/Ab–positive patients were HCV RNA positive. None of anti-HCV-negative or Murex Ag/Ab–negative patients were HCV RNA positive. Based on the HCV RNA assay, the sensitivities for both anti-HCV and Murex Ag/Ab assays were 100%, whereas the specificities of these two assays were 89.7% and 95.4%, respectively. With good sensitivity and specificity, the Murex Ag/Ab assay could be a useful alternative diagnostic tool, especially in immunocompromised populations, such as patients with uremia or those infected with HIV.

  15. Expression of HIV-1 antigens in plants as potential subunit vaccines

    Directory of Open Access Journals (Sweden)

    Tanzer Fiona L

    2008-06-01

    Full Text Available Abstract Background Human immunodeficiency virus type 1 (HIV-1 has infected more than 40 million people worldwide, mainly in sub-Saharan Africa. The high prevalence of HIV-1 subtype C in southern Africa necessitates the development of cheap, effective vaccines. One means of production is the use of plants, for which a number of different techniques have been successfully developed. HIV-1 Pr55Gag is a promising HIV-1 vaccine candidate: we compared the expression of this and a truncated Gag (p17/p24 and the p24 capsid subunit in Nicotiana spp. using transgenic plants and transient expression via Agrobacterium tumefaciens and recombinant tobamovirus vectors. We also investigated the influence of subcellular localisation of recombinant protein to the chloroplast and the endoplasmic reticulum (ER on protein yield. We partially purified a selected vaccine candidate and tested its stimulation of a humoral and cellular immune response in mice. Results Both transient and transgenic expression of the HIV antigens were successful, although expression of Pr55Gag was low in all systems; however, the Agrobacterium-mediated transient expression of p24 and p17/p24 yielded best, to more than 1 mg p24/kg fresh weight. Chloroplast targeted protein levels were highest in transient and transgenic expression of p24 and p17/p24. The transiently-expressed p17/p24 was not immunogenic in mice as a homologous vaccine, but it significantly boosted a humoral and T cell immune response primed by a gag DNA vaccine, pTHGagC. Conclusion Transient agroinfiltration was best for expression of all of the recombinant proteins tested, and p24 and p17/p24 were expressed at much higher levels than Pr55Gag. Our results highlight the usefulness of plastid signal peptides in enhancing the production of recombinant proteins meant for use as vaccines. The p17/p24 protein effectively boosted T cell and humoral responses in mice primed by the DNA vaccine pTHGagC, showing that this plant

  16. [Evaluation of new fourth-generation human immunodeficiency virus antigen and antibody detection assay with enzyme-linked fluorescent immunoassay].

    Science.gov (United States)

    Shima, Takako; Sudo, Koji; Kondo, Makiko; Kurai, Hanako; Sagara, Hiroko; Imai, Mitsunobu

    2007-09-01

    We evaluated the fourth-generation HIV screening assay VIDAS HIV DUOII (DUOII) based on ELFA for simultaneous detection of anti-HIV-1 and anti-HIV-2 antibodies and HIV-1 p24 antigen through comparison with other HIV antigen-antibody detection assays. Materials were 1228 HIV-negative specimens, 95 HIV-antibody-positive specimens, and HIV commercial panels. The specificity of DUOII was 99.8% and sensitivity 100%, detecting all of HIV-1 group M subtype A, B, B', C, D, A/E, F, G, B/D, HIV-1 group O, and HIV-2. The sensitivity test to HIV-1 p24 antigen was 5pg/ mL, higher than other assays. DUOII was equivalent to or superior in detecting results earlier than other assays in an evaluation using 10 commercial HIV-1 seroconversion panels of primary infection. DUOII detects anti-HIV IgM antibody, so no negative sample was found in the second window between p24 antigen disappearance and raised anti-HIV IgG antibody. DUOII has sufficient specificity and sensitivity for HIV screening, and detects primary infection sooner than other assays. These results indicate that DUOII is useful and reliable in HIV screening.

  17. Human leukocyte antigen-e alleles are associated with hepatitis c virus, torque teno virus, and toxoplasma co-infections but are not associated with hepatitis b virus, hepatitis d virus, and GB virus c co-infections in human immunodeficiency virus patients

    Directory of Open Access Journals (Sweden)

    Afiono Agung Prasetyo

    2016-01-01

    Full Text Available Context: Data regarding the distribution of Human Leukocyte Antigen (HLA-E alleles and their association with blood-borne pathogen infections/co-infections are limited for many populations, including Indonesia. Aims: The aim of this study was to analyze the association between HLA-E allelic variants and infection with blood-borne pathogens such as hepatitis B virus (HBV, hepatitis C virus (HCV, hepatitis D virus (HDV, torque teno virus (TTV, GB virus C (GBV-C, and Toxoplasma gondii (T. gondii in Indonesian Javanese human immunodeficiency virus (HIV patients. Settings and Design: A total of 320 anti-HIV-positive blood samples were analyzed for HBV, HCV, HDV, TTV, GBV-C, and T. gondii infection status and its association with HLA-E allelic variants. Materials and Methods: Nucleic acid was extracted from plasma samples and used for the molecular detection of HBV DNA, HCV RNA, HDV RNA, TTV DNA, and GBV-C RNA, whereas hepatitis B surface antigen, anti-HCV, immunoglobulin M and G (IgM and IgG anti-T. gondii were detected through serological testing. The blood samples were genotyped for HLA-E loci using a sequence-specific primer-polymerase chain reaction. Statistical Analysis Used: Either the Chi-square or Fisher′s exact test was performed to analyze the frequency of HLA-E alleles and blood-borne pathogen infections in the population. Odds ratios (ORs were calculated to measure the association between the antibodies found and the participants′ possible risk behaviors. A logistic regression analysis was used to assess the associations. Results: HLA-EFNx010101/0101 was associated with HCV/TTV co-infection (adjusted OR [aOR]: 3.5; 95% confidence interval [CI]: 1.156-10.734; P = 0.027 and IgM/IgG anti-Toxo positivity (aOR: 27.0; 95% CI: 3.626-200.472; P = 0.001. HLA-EFNx010103/0103 was associated with TTV co-infection (aOR: 2.7; 95% CI: 1.509-4.796; P = 0.001. Conclusions: HLA-E alleles in Indonesian Javanese HIV patients were found to be associated

  18. The Cancer-Associated Virus Landscape in HIV Patients with Oral Hairy Leukoplakia, Kaposi's Sarcoma, and Non-Hodgkin Lymphoma

    Directory of Open Access Journals (Sweden)

    Peter D. Burbelo

    2012-01-01

    Full Text Available Although HIV-positive patients are at higher risk for developing a variety of infection-related cancers, the prevalence of infections with the seven known cancer-associated viruses has not been studied. Luciferase immunoprecipitation systems were used to evaluate antiviral antibodies in four 23-person groups: healthy blood donors and HIV-infected patients with oral hairy leukoplakia (OLP, Kaposi's sarcoma (KS, or non-Hodgkin lymphoma (NHL. Antibody profiling revealed that all HIV-positive individuals were strongly seropositive for anti-gp41 and antireverse transcriptase antibodies. However, anti-p24 HIV antibody levels were highly variable and some OLP and KS patients demonstrated weak or negative responses. Profiling two EBV antigens revealed no statistical difference in antibody levels among the three HIV-infected groups. A high frequency of KSHV infection was detected in HIV patients including 100% of KS, 78% of OLP, and 57% of NHL patients. Most HIV-infected subjects (84% showed anti-HBV core antibodies, but only a few showed antibodies against HCV. MCV seropositivity was also common (94% in the HIV-infected individuals and KS patients showed statistically higher antibody levels compared to the OLP and NHL patients. Overall, 68% of the HIV-infected patients showed seropositivity with at least four cancer-associated viruses. Antibody profiles against these and other infectious agents could be useful for enhancing the clinical management of HIV patients.

  19. Detection of virus-specific antigen in the nuclei or nucleoli of cells infected with Zika or Langat virus.

    Science.gov (United States)

    Buckley, A; Gould, E A

    1988-08-01

    Two monoclonal antibodies (MAbs) with molecular specificities for either the viral envelope glycoprotein (MAb 541) or the non-structural NS1 glycoprotein (MAb 109) were derived using West Nile and yellow fever (YF) viruses respectively. Their antigenic reactivity with a large number of flaviviruses was tested by indirect immunofluorescence microscopy. Both produced cytoplasmic fluorescent staining patterns with the homologous virus against which they were raised. Additionally, MAb 541 reacted with two substrains of YF virus whereas MAb 109 reacted with Bussuquara, YF and Ntaya viruses. These reactions were exclusively cytoplasmic. Two unexpected patterns of fluorescent labelling were observed when the antibodies were tested with Zika and Langat viruses. MAb 541 produced fluorescent staining of the nuclei, but not the cytoplasm, of cells infected with Zika virus and MAb 109 labelled only the nucleoli of cells infected with Langat virus. Double-labelling experiments showed that the nuclear fluorescent label was confined to virus-infected cells, and antibody absorption experiments with virus-infected cell packs confirmed the virus specificity of the nuclear antigen. The unexpected presence of virus-specific antigen in the nuclei or nucleoli of Zika or Langat virus-infected cells brings into question the role of the nucleus in flavivirus replication.

  20. Use of the Abbott Architect HIV antigen/antibody assay in a low incidence population.

    Science.gov (United States)

    Dubravac, Terry; Gahan, Thomas F; Pentella, Michael A

    2013-12-01

    With the availability of 4th generation HIV diagnostic tests which are capable of detecting acute infection, Iowa evaluated the 3rd and 4th generation HIV test and compared the performance of these products in a low incidence population. This study was conducted to evaluate the performance of an HIV antigen/antibody combination (4th generation) assay compared to an EIA 3rd generation assay. Over a 4 month period, 2037 specimens submitted for HIV screening were tested by Bio-Rad GS HIV-1/HIV-2 Plus O EIA and the Abbott Architect i1000SR HIV Ag/Ab Combo. The performance characteristics of sensitivity, specificity, positive predictive value and negative predictive value were determined. Of the 2037 specimens tested, there were 13 (0.64%) true positives detected. None of the positive specimens were from patients in the acute phase of infection. The Abbott antigen/antibody combo assay had a sensitivity, specificity, positive-predictive value and negative predictive value of 100%, 99.85%, 81.25%, and 100% respectively. The Bio-Rad EIA assay had a sensitivity, specificity, positive-predictive value and negative predictive value of 100%, 99.80%, 76.47% and 100%, respectively. The EIA had four false positive results which tested negative by the antigen/antibody assay and western blot. In a low-incidence state where early infections are less commonly encountered, the EIA assay and the antigen/antibody assay performed with near equivalency. The antigen/antibody assay had one less false positive result. While no patients were detected in the acute stage of infection, the use of the antigen/antibody assay presents the opportunity to detect an infected patient sooner and prevent transmission to others. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. The porcine circovirus type 1 capsid gene promoter improves antigen expression and immunogenicity in a HIV-1 plasmid vaccine

    Directory of Open Access Journals (Sweden)

    Burger Marieta

    2011-02-01

    Full Text Available Abstract Background One of the promising avenues for development of vaccines against Human immunodeficiency virus type 1 (HIV-1 and other human pathogens is the use of plasmid-based DNA vaccines. However, relatively large doses of plasmid must be injected for a relatively weak response. We investigated whether genome elements from Porcine circovirus type 1 (PCV-1, an apathogenic small ssDNA-containing virus, had useful expression-enhancing properties that could allow dose-sparing in a plasmid vaccine. Results The linearised PCV-1 genome inserted 5' of the CMV promoter in the well-characterised HIV-1 plasmid vaccine pTHgrttnC increased expression of the polyantigen up to 2-fold, and elicited 3-fold higher CTL responses in mice at 10-fold lower doses than unmodified pTHgrttnC. The PCV-1 capsid gene promoter (Pcap alone was equally effective. Enhancing activity was traced to a putative composite host transcription factor binding site and a "Conserved Late Element" transcription-enhancing sequence previously unidentified in circoviruses. Conclusions We identified a novel PCV-1 genome-derived enhancer sequence that significantly increased antigen expression from plasmids in in vitro assays, and improved immunogenicity in mice of the HIV-1 subtype C vaccine plasmid, pTHgrttnC. This should allow significant dose sparing of, or increased responses to, this and other plasmid-based vaccines. We also report investigations of the potential of other circovirus-derived sequences to be similarly used.

  2. Hepatitis B virus and HIV infection among patients with primary ...

    African Journals Online (AJOL)

    Background: Hepatitis B virus (HBV) is the commonest cause of primary hepatocellular (PHC) carcinoma worldwide. Coinfection with the HIV leads to more rapid progression of liver disease. Objectives: We described prevalence of HBV and HIV among patients with PHC admitted to Mulago Hospital, Kampala, Uganda.

  3. Anti-Human Immunodeficiency Virus (HIV) Agents | Okolie | Journal ...

    African Journals Online (AJOL)

    This article gives a brief review of anti-retroviral agents with activity against the Human Immunodeficiency Virus (HIV) the causative agen of Acquired Immunodeficiency Syndrome (AIDS). It also outlines the principles, mode of action of anti-HIV agents and their sites of therapeutic intervention. Zidovudine or Azidothymidine ...

  4. Prevalence of Anaemia Among Human Immunodeficiency Virus (HIV)

    African Journals Online (AJOL)

    Background: Anaemia is the most commonly encountered haematological abnormality in human immunodeficiency virus (HIV) positive patients with estimates climbing as high as 95% depending on clinical settings. The twin effects of HIV infection and anaemia in pregnancy is associated with adverse maternal and ...

  5. Antiviral Functions of Human Immunodeficiency Virus Type 1 (HIV-1)-Specific IgG Antibodies: Effects of Antiretroviral Therapy and Implications for Therapeutic HIV-1 Vaccine Design.

    Science.gov (United States)

    French, Martyn A; Tjiam, M Christian; Abudulai, Laila N; Fernandez, Sonia

    2017-01-01

    Contemporary antiretroviral therapy (ART) is effective and tolerable for long periods of time but cannot eradicate human immunodeficiency virus type 1 (HIV-1) infection by either elimination of viral reservoirs or enhancement of HIV-1-specific immune responses. Boosting "protective" HIV-1-specific immune responses by active or passive immunization will therefore be necessary to control or eradicate HIV-1 infection and is currently the topic of intense investigation. Recently reported studies conducted in HIV patients and non-human primate (NHP) models of HIV-1 infection suggest that HIV-1-specific IgG antibody responses may contribute to the control of HIV-1 infection. However, production of IgG antibodies with virus neutralizing activity by vaccination remains problematic and while vaccine-induced natural killer cell-activating IgG antibodies have been shown to prevent the acquisition of HIV-1 infection, they may not be sufficient to control or eradicate established HIV-1 infection. It is, therefore, important to consider other functional characteristics of IgG antibody responses. IgG antibodies to viruses also mediate opsonophagocytic antibody responses against virions and capsids that enhance the function of phagocytic cells playing critical roles in antiviral immune responses, particularly conventional dendritic cells and plasmacytoid dendritic cells. Emerging evidence suggests that these antibody functions might contribute to the control of HIV-1 infection. In addition, IgG antibodies contribute to the intracellular degradation of viruses via binding to the cytosolic fragment crystallizable (Fc) receptor tripartite motif containing-21 (TRIM21). The functional activity of an IgG antibody response is influenced by the IgG subclass content, which affects binding to antigens and to Fcγ receptors on phagocytic cells and to TRIM21. The IgG subclass content and avidity of IgG antibodies is determined by germinal center (GC) reactions in follicles of lymphoid tissue

  6. High-level HIV-1 viremia suppresses viral antigen-specific CD4+ T cell proliferation

    OpenAIRE

    McNeil, Andrew C.; Shupert, W. Lesley; Iyasere, Christiana A.; Hallahan, Claire W.; Mican, JoAnn; Davey, Richard T.; Connors, Mark

    2001-01-01

    In chronic viral infections of humans and experimental animals, virus-specific CD4+ T cell function is believed to be critical for induction and maintenance of host immunity that mediates effective restriction of viral replication. Because in vitro proliferation of HIV-specific memory CD4+ T cells is only rarely demonstrable in HIV-infected individuals, it is presumed that HIV-specific CD4+ T cells are killed upon encountering the virus, and maintenance of CD4+ T cell responses in some patien...

  7. Antigenic and genetic comparisons of Japanese and Australian Simbu serogroup viruses: evidence for the recovery of natural virus reassortants.

    Science.gov (United States)

    Akashi, H; Kaku, Y; Kong, X; Pang, H

    1997-08-01

    The antigenicity and RNA genome structures of five Simbu serogroup bunyaviruses isolated in Japan and Australia were analyzed using monoclonal antibodies (Mabs) raised to Akabane (AKA) virus and oligonucleotide fingerprinting. The virion surface glycoprotein (G1) and the nucleocapsid (N) protein of heterologous viruses showed no reactivity to the Mabs, while the AKA-derived anti-G1 Mab (2F1) reacted with Peaton virus and all three AKA anti-N Mabs reacted with Tinaroo (TIN) virus at almost the same antibody titers as the homologous virus. Oligonucleotide fingerprinting analyses indicated that the three RNA species of all the viruses were unique and distinguishable. However, AKA and TIN viruses exhibited very similar S RNA oligonucleotide fingerprints, while the L and M RNA fingerprints were quite different. The S RNA sequence of TIN virus has been determined and compared with that of AKA and Aino viruses. The results revealed 95.1% S sequence homology between the AKA and TIN viruses. The antigenic and genetic comparisons of AKA and TIN viruses suggest that the two viruses may represent naturally occurring reassortant viruses.

  8. Antibody responses to a major Pneumocystis carinii antigen in human immunodeficiency virus-infected patients with and without P. carinii pneumonia

    DEFF Research Database (Denmark)

    Lundgren, Bettina; Lundgren, Jens Dilling; Nielsen, T

    1992-01-01

    Antibody responses to a major purified human Pneumocystis carinii surface antigen (gp95) were determined by ELISA in human immunodeficiency virus (HIV)-infected patients. Serum IgG directed against gp95 was measured in 129 consecutive HIV-infected patients who underwent bronchoscopy for evaluation...... was higher (mean optical density ratio: 0.6 vs. 0.23 and 0.2, respectively; P less than .01). Changes in antibody response were investigated in 78 patients for whom serial serum samples taken around the time of bronchoscopy were available. Of the 47 patients with verified PCP, 20 (43%) mounted an antibody...

  9. Sero-prevalence of Human Immunodeficiency Virus (HIV) and ...

    African Journals Online (AJOL)

    Three hundred and seven (307) healthy blood donors aged 18 – 55 years were used to determine the sero-prevalence of Human Immunodeficiency Virus (HIV) and Hepatitis B virus (HBV) in Yola, Nigeria. The association between donors' age, occupation and marital status and the prevalence of the infections among blood ...

  10. Imaging and tracking HIV viruses in human cervical mucus

    Science.gov (United States)

    Boukari, Fatima; Makrogiannis, Sokratis; Nossal, Ralph; Boukari, Hacène

    2016-09-01

    We describe a systematic approach to image, track, and quantify the movements of HIV viruses embedded in human cervical mucus. The underlying motivation for this study is that, in HIV-infected adults, women account for more than half of all new cases and most of these women acquire the infection through heterosexual contact. The endocervix is believed to be a susceptible site for HIV entry. Cervical mucus, which coats the endocervix, should play a protective role against the viruses. Thus, we developed a methodology to apply time-resolved confocal microscopy to examine the motion of HIV viruses that were added to samples of untreated cervical mucus. From the images, we identified the viruses, tracked them over time, and calculated changes of the statistical mean-squared displacement (MSD) of each virus. Approximately half of tracked viruses appear constrained while the others show mobility with MSDs that are proportional to τα+ν2τ2, over time range τ, depicting a combination of anomalous diffusion (0viruses. Although a more extensive study is warranted, these results support the assumption of mucus being a barrier against the motion of these viruses.

  11. Hepatitis B and HIV co-infection in pregnant women: indication for routine antenatal hepatitis B virus screening in a high HIV prevalence setting.

    Science.gov (United States)

    Thumbiran, N V; Moodley, D; Parboosing, R; Moodley, P

    2014-04-01

    Sub-Saharan Africa is endemic for hepatitis B virus (HBV) and human immunodeficiency virus (HIV) infections. HBV/HIV co-infection in women of reproductive age is of clinical and public health importance because these women constitute a significant reservoir for horizontal and perinatal HBV transmission. Childhood HBV vaccination from 6 weeks of age protects most children against chronic HBV infection. However, infants born to HBV/HIV co-infected women are more likely to be infected perinatally, with an increased risk of chronic hepatitis, than infants born to HBV mono-infected women. The aim of our study was to establish the prevalence of HBV infection and HBV/HIV co-infection in pregnant women in KwaZulu-Natal, South Africa, to inform antenatal HBV screening and childhood immunisation policies in South Africa. Stored plasma specimens obtained from 570 pregnant women were tested for hepatitis B surface antigen (HBsAg) and HBV infectivity, as characterised by the presence of hepatitis B e antigen (HBeAg) and/or HBV DNA load. The antenatal HIV prevalence and HBsAg prevalence in this study were 41.6% and 5.3% (95% confidence interval (CI) 3.4 - 7.1), respectively. Overall, 3.1% (95% CI 1.7 - 4.6) of pregnant women were HBV/HIV co-infected, with HBeAg positivity and the HBV DNA load being significantly higher in co-infected women. We report a 5.3% HBV prevalence and a 3.1% HBV/HIV co-infection prevalence in pregnant women from this HIV-endemic region. Routine antenatal HBV screening will allow early identification of neonates who require HBV active-passive immunoprophylaxis at birth. This strategy, together with antenatal antiretrovirals, will reduce the risk of perinatal HBV transmission, especially in high-risk HBV/ HIV co-infected pregnant women.

  12. Human immunodeficiency virus (HIV) seropositivity and hepatitis B surface antigenemia (HBSAG) among blood donors in Benin city, Edo state, Nigeria.

    Science.gov (United States)

    Umolu, Patience Idia; Okoror, Lawrence Ehis; Orhue, Philip

    2005-03-01

    Human Immunodeficiency Virus and Hepatitis B virus are blood borne pathogens that can be transmitted through blood transfusion and could pose a huge problem in areas where mechanisms of ensuring blood safety are suspect. This study became necessary in a population where most of the blood for transfusion is from commercial blood donors. A total of 130 donors comprising 120 commercial donors and 10 voluntary donors were tested for antibodies to human immunodeficiency virus and hepatitis B surface antigen in Benin city using Immunocomb HIV - 1 and 2 Biospot kit and Quimica Clinica Aplicada direct latex agglutination method respectively. Thirteen (10%) samples were HIV seropositive and 7(5.8%) were HBsAg positive. The age bracket 18 - 25years had the highest numbers of donors and also had the highest number of HBsAg positive cases (7.8%) while the age group 29 - 38years had highest number of HIV seropositive cases. High prevalence of HIV antibodies and Hepatitis B surface antigen was found among commercial blood donors. Appropriate and compulsory screening of blood donors using sensitive methods, must be ensured to prevent post transfusion hepatitis and HIV.

  13. Human Leukocyte Antigen (HLA and Immune Regulation: How Do Classical and Non-Classical HLA Alleles Modulate Immune Response to Human Immunodeficiency Virus and Hepatitis C Virus Infections?

    Directory of Open Access Journals (Sweden)

    Nicole B. Crux

    2017-07-01

    Full Text Available The genetic factors associated with susceptibility or resistance to viral infections are likely to involve a sophisticated array of immune response. These genetic elements may modulate other biological factors that account for significant influence on the gene expression and/or protein function in the host. Among them, the role of the major histocompatibility complex in viral pathogenesis in particular human immunodeficiency virus (HIV and hepatitis C virus (HCV, is very well documented. We, recently, added a novel insight into the field by identifying the molecular mechanism associated with the protective role of human leukocyte antigen (HLA-B27/B57 CD8+ T cells in the context of HIV-1 infection and why these alleles act as a double-edged sword protecting against viral infections but predisposing the host to autoimmune diseases. The focus of this review will be reexamining the role of classical and non-classical HLA alleles, including class Ia (HLA-A, -B, -C, class Ib (HLA-E, -F, -G, -H, and class II (HLA-DR, -DQ, -DM, and -DP in immune regulation and viral pathogenesis (e.g., HIV and HCV. To our knowledge, this is the very first review of its kind to comprehensively analyze the role of these molecules in immune regulation associated with chronic viral infections.

  14. Human Leukocyte Antigen (HLA) and Immune Regulation: How Do Classical and Non-Classical HLA Alleles Modulate Immune Response to Human Immunodeficiency Virus and Hepatitis C Virus Infections?

    Science.gov (United States)

    Crux, Nicole B.; Elahi, Shokrollah

    2017-01-01

    The genetic factors associated with susceptibility or resistance to viral infections are likely to involve a sophisticated array of immune response. These genetic elements may modulate other biological factors that account for significant influence on the gene expression and/or protein function in the host. Among them, the role of the major histocompatibility complex in viral pathogenesis in particular human immunodeficiency virus (HIV) and hepatitis C virus (HCV), is very well documented. We, recently, added a novel insight into the field by identifying the molecular mechanism associated with the protective role of human leukocyte antigen (HLA)-B27/B57 CD8+ T cells in the context of HIV-1 infection and why these alleles act as a double-edged sword protecting against viral infections but predisposing the host to autoimmune diseases. The focus of this review will be reexamining the role of classical and non-classical HLA alleles, including class Ia (HLA-A, -B, -C), class Ib (HLA-E, -F, -G, -H), and class II (HLA-DR, -DQ, -DM, and -DP) in immune regulation and viral pathogenesis (e.g., HIV and HCV). To our knowledge, this is the very first review of its kind to comprehensively analyze the role of these molecules in immune regulation associated with chronic viral infections. PMID:28769934

  15. Role of GB virus C in modulating HIV disease

    Science.gov (United States)

    Schwarze-Zander, Carolynne; Blackard, Jason T; Rockstroh, Juergen K

    2012-01-01

    GB virus C (GBV-C) is a member of the Flaviviridae family and the most closely related human virus to HCV. However, GBV-C does not replicate in hepatocytes, but rather in lymphocytes. GBV-C has a worldwide distribution and is transmitted sexually, parenterally and through mother-to-child transmission. Thus, co-infection with HCV and HIV is common. Until now, no human disease has been associated with GBV-C infection. However, there are several reports of a beneficial effect of GBV-C on HIV disease progression in vivo. Different mechanisms to explain these observations have been proposed, including modification of antiviral cytokine production, HIV co-receptor expression, direct inhibition of HIV-1 entry, T-cell activation and Fas-mediated apoptosis. Further understanding of these mechanisms may open new strategies for the treatment of HIV/AIDS. PMID:22702320

  16. Antibody responses to a major Pneumocystis carinii antigen in human immunodeficiency virus-infected patients with and without P. carinii pneumonia

    DEFF Research Database (Denmark)

    Lundgren, Bettina; Lundgren, Jens Dilling; Nielsen, T

    1992-01-01

    Antibody responses to a major purified human Pneumocystis carinii surface antigen (gp95) were determined by ELISA in human immunodeficiency virus (HIV)-infected patients. Serum IgG directed against gp95 was measured in 129 consecutive HIV-infected patients who underwent bronchoscopy for evaluation...... of pulmonary symptoms. Significantly more patients with P. carinii pneumonia (PCP) had detectable antibodies compared with HIV-infected patients without PCP and with HIV-negative controls (50 [66%] of 76 vs. 18 [34%] of 53 and 7 [35%] of 20, respectively; P less than .001), and the level of antibody response...... was higher (mean optical density ratio: 0.6 vs. 0.23 and 0.2, respectively; P less than .01). Changes in antibody response were investigated in 78 patients for whom serial serum samples taken around the time of bronchoscopy were available. Of the 47 patients with verified PCP, 20 (43%) mounted an antibody...

  17. HIV-associated benign lymphoepithelial cysts of the parotid glands confirmed by HIV-1 p24 antigen immunostaining.

    Science.gov (United States)

    Sekikawa, Yoshiyuki; Hongo, Igen

    2017-09-28

    Approximately 1%-10% of patients with HIV infection have been reported to have salivary gland enlargement. Parotid swelling in patients with HIV is often associated with salivary gland disease, including benign lymphoepithelial cysts (BLECs). The presence of BLEC can serve as an indicator of HIV infection, and the diagnosis of HIV-associated BLEC is usually based on clinical course, HIV confirmatory blood testing, such as western blot or viral detection, and imaging studies, but not on biopsies or immunostaining. To exclude other diseases such as tuberculosis and malignant lymphoma and to further improve the diagnostic accuracy of BLEC, the detection of the HIV-1 p24 antigen by immunohistochemistry is a useful diagnostic method. We report a case of a 65-year-old Japanese man with swelling of the parotid glands and HIV-associated BLEC confirmed via HIV-1 p24 immunohistochemical staining. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  18. Antigen processing influences HIV-specific cytotoxic T lymphocyte immunodominance

    DEFF Research Database (Denmark)

    Tenzer, Stefan; Wee, Edmund; Burgevin, Anne

    2009-01-01

    Although cytotoxic T lymphocytes (CTLs) in people infected with human immunodeficiency virus type 1 can potentially target multiple virus epitopes, the same few are recognized repeatedly. We show here that CTL immunodominance in regions of the human immunodeficiency virus type 1 group-associated ......Although cytotoxic T lymphocytes (CTLs) in people infected with human immunodeficiency virus type 1 can potentially target multiple virus epitopes, the same few are recognized repeatedly. We show here that CTL immunodominance in regions of the human immunodeficiency virus type 1 group...... and functional analyses demonstrated that proteasomal cleavage 'preferences' modulated the number and length of epitope-containing peptides, thereby affecting the response avidity and clonality of T cells. Cleavage patterns were affected by both flanking and intraepitope CTL-escape mutations. Our analyses show...

  19. Studies on antigenic and genomic properties of Brazilian rabies virus isolates

    NARCIS (Netherlands)

    Schaefer, R.; Batista, H.B.; Franco, A.C.; Rijsewijk, F.A.M.; Roehe, P.M.

    2005-01-01

    Despite the recognized stability of rabies virus, differences among isolates from different species have been found. This work was carried out with the aim to identify antigenic and genomic differences in Brazilian rabies virus isolates and to verify whether such alterations would bear any

  20. Antigenic and genetic evolution of swine influenza A (H3N2) viruses in Europe

    NARCIS (Netherlands)

    J.C. de Jong (Jan); D.J. Smith (Derek James); A.S. Lapedes (Alan); I. Donatelli; L. Campitelli; G. Barigazzi; K. van Reeth; T.C. Jones (Terry); G.F. Rimmelzwaan (Guus); A.D.M.E. Osterhaus (Albert); R.A.M. Fouchier (Ron)

    2007-01-01

    textabstractIn the early 1970s, a human influenza A/Port Chalmers/1/73 (H3N2)-like virus colonized the European swine population. Analyses of swine influenza A (H3N2) viruses isolated in The Netherlands and Belgium revealed that in the early 1990s, antigenic drift had occurred, away from A/Port

  1. Antigenic structure of the capsid protein of rabbit haemorrhagic disease virus

    DEFF Research Database (Denmark)

    Martinez-Torrecuadrada, Jorge L.; Cortes, Elena; Vela, Carmen

    1998-01-01

    Rabbit haemorrhagic disease virus (RHDV) causes an important disease in rabbits. The virus capsid is composed of a single 60 kDa protein. The capsid protein gene was cloned in Escherichia coli using the pET3 system, and the antigenic structure of RHDV VP60 was dissected using 11 monoclonal...

  2. Liver fibrosis progression in HIV/hepatitis C virus coinfected patients with normal aminotransferases levels

    Directory of Open Access Journals (Sweden)

    Fábio Heleno de Lima Pace

    2012-08-01

    Full Text Available INTRODUCTION: Approximately 30% of hepatitis C virus (HCV monoinfected patients present persistently normal alanine aminotransferase (ALT levels. Most of these patients have a slow progression of liver fibrosis. Studies have demonstrated the rate of liver fibrosis progression in hepatitis C virus-human immunodeficiency virus (HCV-HIV coinfected patients is faster than in patients infected only by HCV. Few studies have evaluated the histological features of chronic hepatitis C in HIV-infected patients with normal ALT levels. METHODS: HCV-HIV coinfected patients (HCV-RNA and anti-HIV positive with known time of HCV infection (intravenous drugs users were selected. Patients with hepatitis B surface antigen (HBsAg positive or hepatitis C treatment before liver biopsy were excluded. Patients were considered to have a normal ALT levels if they had at least 3 normal determinations in the previous 6 months prior to liver biopsy. All patients were submitted to liver biopsy and METAVIR scale was used. RESULTS: Of 50 studied patients 40 (80% were males. All patients were treated with antiretroviral therapy. The ALT levels were normal in 13 (26% patients. HCV-HIV co-infected patients with normal ALT levels had presented means of the liver fibrosis stages (0.77±0.44 versus 1.86±1.38; p<0.001 periportal inflammatory activity (0.62±0.77 versus 2.24±1.35; p<0.001 and liver fibrosis progression rate (0.058±0.043 fibrosis unit/year versus 0.118±0.102 fibrosis unit/year significantly lower as compared to those with elevated ALT. CONCLUSIONS: HCV-HIV coinfected patients with persistently normal ALTs showed slower progression of liver fibrosis. In these patients the development of liver cirrhosis is improbable.

  3. T-cell dysfunction in HIV infection: anergy due to defective antigen-presenting cell function?

    NARCIS (Netherlands)

    Meyaard, L.; Schuitemaker, H.; Miedema, F.

    1993-01-01

    Before CD4+ T cells are depleted, T cells in asymptomatic HIV-infected individuals are functionally abnormal. These T cells are programmed for death, are non-responsive and fail to produce interleukin-2 after antigenic stimulation. Our view is that these different T-cell abnormalities are explained

  4. Hepatitis B virus and hepatitis C virus infection among HIV-1-infected injection drug users in Dali, China: prevalence and infection status in a cross-sectional study.

    Science.gov (United States)

    Dong, Yuan; Qiu, Chao; Xia, Xueshan; Wang, Jing; Zhang, Haiyan; Zhang, Xiaoyan; Xu, Jianqing

    2015-04-01

    To assess the prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection and to investigate their mutual influences on infection status among human immunodeficiency virus type 1 (HIV-1)-seropositive injection drug users (IDUs). A cross-sectional study was conducted among HIV infected IDUs in Dali, China. The participants were tested for serological markers of HBV and HCV infection, alanine transaminase (ALT) activity and CD4(+) T cell count. HCV genotype was determined by sequencing. Of 529 patients, 498 (94.1 %) HIV infected IDUs agreed to participate. The overall prevalence of HCV infection (anti-HCV antibody positive) and spontaneous HCV clearance were 90.8 % (452/498) and 21.5 % (97/452), respectively. Of 411 subjects who had not received HBV vaccine, 296 (72.0 %) were positive for antibody against HBV core antigen (HBcAb), while 274 (66.7 %) were positive for both HCV antibody and HBcAb. HBV antigens were detected in 52 of the HBV-infected subjects (17.6 %). HCV clearance was associated with HBV antigenemia (p = 0.0002) and higher CD4(+) T cell count (p = 0.0294). Resolved HBV infection was associated with HCV genotype 3 (p = 0.0365). HBV and HCV infection are highly prevalent and mutually influence infection status in HIV-1 infected IDUs in Dali, China.

  5. Antigenic Patterns and Evolution of the Human Influenza A (H1N1) Virus.

    Science.gov (United States)

    Liu, Mi; Zhao, Xiang; Hua, Sha; Du, Xiangjun; Peng, Yousong; Li, Xiyan; Lan, Yu; Wang, Dayan; Wu, Aiping; Shu, Yuelong; Jiang, Taijiao

    2015-09-28

    The influenza A (H1N1) virus causes seasonal epidemics that result in severe illnesses and deaths almost every year. A deep understanding of the antigenic patterns and evolution of human influenza A (H1N1) virus is extremely important for its effective surveillance and prevention. Through development of antigenicity inference method for human influenza A (H1N1), named PREDAC-H1, we systematically mapped the antigenic patterns and evolution of the human influenza A (H1N1) virus. Eight dominant antigenic clusters have been inferred for seasonal H1N1 viruses since 1977, which demonstrated sequential replacements over time with a similar pattern in Asia, Europe and North America. Among them, six clusters emerged first in Asia. As for China, three of the eight antigenic clusters were detected in South China earlier than in North China, indicating the leading role of South China in H1N1 transmission. The comprehensive view of the antigenic evolution of human influenza A (H1N1) virus can help formulate better strategy for its prevention and control.

  6. Primaer HIV-infektion

    DEFF Research Database (Denmark)

    Pedersen, C; Pedersen, B K

    1996-01-01

    , oesophageal candidiasis, meningoencephalitis, rhabdomyolysis and epiglottitis have been reported. The diagnosis of the acute HIV infection syndrome can be established by demonstrating antibodies to HIV or by demonstration of HIV antigen positivity. Detection of virus through culture or PCR may prove...

  7. Hepatitis B virus core antigen: synthesis in Escherichia coli and application in diagnosis.

    Science.gov (United States)

    Stahl, S; MacKay, P; Magazin, M; Bruce, S A; Murray, K

    1982-01-01

    Fragments of hepatitis B virus DNA cloned in plasmid pBR322 carrying the gene for the viral core antigen have been placed under the control of the lac promoter of Escherichia coli. Several of the new recombinants direct higher levels of synthesis of the antigen, but the degree of enhancement varies with the different structures of the plasmids and hence the mRNAs produced. The antigen in crude bacterial lysates is a satisfactory diagnostic reagent for antibodies to the core antigen in serum samples. Images PMID:7041126

  8. [A case of hepatitis B virus/human immunodeficiency virus coinfection in a patient who achived hepatitis B surface antigen seroclearance after interferon therapy followed by antiretroviral therapy without developing immune reconstitution inflammatory syndrome].

    Science.gov (United States)

    Mitsumoto, Fujiko; Murata, Masayuki; Ikezaki, Hiroaki; Ogawa, Eiichi; Taniai, Hiroaki; Toyoda, Kazuhiro; Otaguro, Shigeru; Kainuma, Mosaburo; Okada, Kyoko; Furusyo, Norihiro; Hayashi, Jun

    2012-11-01

    Coinfection with human immunodeficiency virus (HIV) and hepatitis B virus (HBV) is common worldwide. The current guidelines for the treatment of HIV infection recommend that HIV patients coinfected with HBV receive antiretoroviral therapy (ART) with two nucleoside analogs against HBV. However, an increase in liver enzymes that is usually attributed to HBV immune reconstitution inflammatory syndrome (IRIS) sometimes occurs in HBV/HIV-coinfected patients after the commencement of ART. We report a case of HBV/HIV-coinfection in which the chronic hepatitis B was successfully treated using interferon (IFN) therapy followed by ART without the development of IRIS. A Japanese man in thirties was referred to our hospital because of an acute HIV infection two months after the diagnosis of an acute HBV infection, which had progressed to a chronic HBV infection. The laboratory test results were as follows:hepatitis B surface antigen (HBsAg) positive, hepatitis B e antigen (HBeAg) positive, HBV DNA level of 8.8 Log copies/mL, HBV genotype A, alanine aminotransferase of 834 IU/L, HIV RNA level of 5 Log copies/mL, and a CD4+ T cell count of 437/microL. The initial treatment was natural IFNalpha therapy for chronic hepatitis B, and HBeAg seroclearance was achieved 20 weeks after the start of therapy. Four months after the end of IFN therapy for 24 weeks, ART including tenofovir and emtricitabine against HBV was commenced. Six months after starting ART, the patient's serum HBV DNA level had decreased and become undetectable and HBsAg seroclearance was achieved without an elevation in liver enzymes. The present case suggests that IFN therapy prior to ART contributes to a successful outcome for chronic hepatitis B patients coinfected with HIV, if the HIV status does not require the immediate start of ART.

  9. Antigenic determinants of influenza virus haemagglutinin. X. A comparison of the physical and antigenic properties of monomeric and trimeric forms.

    Science.gov (United States)

    Nestorowicz, A; Laver, G; Jackson, D C

    1985-08-01

    Haemagglutinin prepared from influenza virus A/Memphis/1/71 by bromelain digestion was centrifuged through continuous sucrose gradients buffered at pH 7.4 or pH 4.9. From these gradients were isolated two forms of the protein which displayed different equilibrium sedimentation properties. One species behaved as a molecule with a mol. wt. of 190 000, the other with a mol. wt. of 70 000. These results are consistent with the separation of trimeric and monomeric haemagglutinin. A comparison of their antigenic properties, using monoclonal antibodies raised against intact virus, showed that major antigenic differences occur between the two forms of haemagglutinin. None of the monoclonal antibodies reacted with haemagglutinin denatured by reduction and alkylation.

  10. Psoralen Inactivation of Viruses: A Process for the Safe Manipulation of Viral Antigen and Nucleic Acid

    Directory of Open Access Journals (Sweden)

    Katherine Schneider

    2015-11-01

    Full Text Available High consequence human pathogenic viruses must be handled at biosafety level 2, 3 or 4 and must be rendered non-infectious before they can be utilized for molecular or immunological applications at lower biosafety levels. Here we evaluate psoralen-inactivated Arena-, Bunya-, Corona-, Filo-, Flavi- and Orthomyxoviruses for their suitability as antigen in immunological processes and as template for reverse transcription PCR and sequencing. The method of virus inactivation using a psoralen molecule appears to have broad applicability to RNA viruses and to leave both the particle and RNA of the treated virus intact, while rendering the virus non-infectious.

  11. Virus-specific nucleic acids in SV40-exposed hamster embryo cell lines: correlation with S and T antigens.

    Science.gov (United States)

    Levin, M J; Oxman, M N; Diamandopoulos, G T; Levine, A S; Henry, P H; Enders, J F

    1969-02-01

    A number of homologous SV40-exposed hamster embryonic cell lines were examined for the presence of RNA complementary to SV40 DNA. Only those lines containing the SV40 T antigen were found to have such virus-specific RNA. In lines containing the SV40 S antigen, but not the SV40 T antigen, virus-specific RNA was not detected. These findings suggest that the S antigen is not coded for directly by the SV40 genome.

  12. VIRUS-SPECIFIC NUCLEIC ACIDS IN SV40-EXPOSED HAMSTER EMBRYO CELL LINES: CORRELATION WITH S AND T ANTIGENS*

    Science.gov (United States)

    Levin, Myron J.; Oxman, Michael N.; Diamandopoulos, George Th.; Levine, Arthur S.; Henry, Patrick H.; Enders, John F.

    1969-01-01

    A number of homologous SV40-exposed hamster embryonic cell lines were examined for the presence of RNA complementary to SV40 DNA. Only those lines containing the SV40 T antigen were found to have such virus-specific RNA. In lines containing the SV40 S antigen, but not the SV40 T antigen, virus-specific RNA was not detected. These findings suggest that the S antigen is not coded for directly by the SV40 genome. PMID:4307716

  13. 75 FR 51273 - Expanded Human Immunodeficiency Virus (HIV) Testing for Disproportionately Affected Populations

    Science.gov (United States)

    2010-08-19

    ... Announcement CDC-RFA-PS10-10138, ``Expanded Human Immunodeficiency Virus (HIV) Testing for Disproportionately... Assistance Number: 93.523 The Affordable Care Act: Human Immunodeficiency Virus (HIV) Prevention and Public... Number 93.523 The Affordable Care Act: Human Immunodeficiency Virus (HIV) Prevention and Public Health...

  14. 21 CFR 610.46 - Human immunodeficiency virus (HIV) “lookback” requirements.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Human immunodeficiency virus (HIV) âlookbackâ... Disease Agents § 610.46 Human immunodeficiency virus (HIV) “lookback” requirements. (a) If you are an... calendar days after a donor tests reactive for evidence of human immunodeficiency virus (HIV) infection...

  15. Antibody to histo-blood group A antigen neutralizes HIV produced by lymphocytes from blood group A donors but not from blood group B or O donors

    DEFF Research Database (Denmark)

    Arendrup, M; Hansen, J E; Clausen, H

    1991-01-01

    for virus neutralization by the monoclonal antibody (MAb) AH16 directed against the blood group A epitope. MAb AH16 was previously shown to inhibit cell-free virus infection using HTLV-IIIB propagated in H9 cells. AH16 showed a concentration-dependent inhibition of the HTLV-IIIB/lyA isolate but did...... not inhibit the HTLV-IIIB/lyB or the HTLV-IIIB/lyO isolate. Specificity of the MAb-mediated inhibition was shown using A-antigen (tetrasaccharide). Thus, HIV infection of PBMC from donors with blood type A appears to induce expression of host-cell-encoded carbohydrate blood group A epitope on HIV which can...

  16. Rapid Assay for Simultaneous Detection and Differentiation of Immunoglobulin G Antibodies to Human Immunodeficiency Virus Type 1 (HIV-1) Group M, HIV-1 Group O, and HIV-2

    OpenAIRE

    Vallari, Ana S.; Hickman, Robert K.; Hackett, John R.; Brennan, Catherine A.; Varitek, Vincent A.; Devare, Sushil G.

    1998-01-01

    A rapid immunodiagnostic test that detects and discriminates human immunodeficiency virus (HIV) infections on the basis of viral type, HIV type 1 (HIV-1) group M, HIV-1 group O, or HIV-2, was developed. The rapid assay for the detection of HIV (HIV rapid assay) was designed as an instrument-free chromatographic immunoassay that detects immunoglobulin G (IgG) antibodies to HIV. To assess the performance of the HIV rapid assay, 470 HIV-positive plasma samples were tested by PCR and/or Western b...

  17. Antigenic and genetic characterization of influenza viruses circulating in Bulgaria during the 2015/2016 season.

    Science.gov (United States)

    Korsun, Neli; Angelova, Svetla; Gregory, Viki; Daniels, Rodney; Georgieva, Irina; McCauley, John

    2017-04-01

    Influenza virological surveillance is an essential tool for early detection of novel genetic variants of epidemiologic and clinical significance. The aim of this study was to determine the antigenic and molecular characteristics of influenza viruses circulating in Bulgaria during the 2015/2016 season. The season was characterized by dominant circulation of A(H1N1)pdm09 viruses, accounting for 66% of detected influenza viruses, followed by B/Victoria-lineage viruses (24%) and A(H3N2) viruses (10%). All sequenced influenza A(H1N1)pdm09, A(H3N2) and B/Victoria-lineage viruses belonged to the 6B.1, 3C.2a and 1A genetic groups, respectively. Amino acid analysis of 57 A(H1N1)pdm09 isolates revealed the presence of 16 changes in hemagglutinin (HA) compared to the vaccine virus, five of which occurred in four antigenic sites, together with 16 changes in neuraminidase (NA) and a number of substitutions in proteins MP, NP, NS and PB2. Despite the many amino acid substitutions, A(H1N1)pdm09 viruses remained antigenically closely related to A/California/7/2009 vaccine virus. Bulgarian A(H3N2) strains (subclade 3C.2a) showed changes at 11 HA positions four of which were located in antigenic sites A and B, together with 6 positions in NA, compared to the subclade 3C.3a vaccine virus. They contained unique HA1 substitutions N171K, S312R and HA2 substitutions I77V and G155E compared to Bulgarian 3C.2a viruses of the previous season. All 20 B/Victoria-lineage viruses sequenced harboured two substitutions in the antigenic 120-loop region of HA, and 5 changes in NA, compared to the B/Brisbane/60/2008 vaccine virus. The results of this study reaffirm the continuous genetic variability of circulating seasonal influenza viruses and the need for continued systematic antigenic and molecular surveillance. Copyright © 2017 The Francis Crick Institute. Published by Elsevier B.V. All rights reserved.

  18. 110 HUMAN IMMUNODEFICIENCY VIRUS (HIV) SEROPOSITIVITY ...

    African Journals Online (AJOL)

    patients with ocular disorders and who are otherwise healthy looking may infact be HIV seropositive and as such it may be necessary to observe all rules relating to HIV transmission so as to prevent ... from the tear fluid, conjunctiva of HIV positive but asymptomatic individuals (5). There have also been reports of health care ...

  19. Human immunodeficiency virus (HIV) infection in tuberculosis ...

    African Journals Online (AJOL)

    BACKGROUND: In a country with a rapidly spreading HIV epidemic information regarding HIV and TB Co-infection are lacking. OBJECTIVES: To determine the prevalence of HIV infection in a representative sample of sputum-positive tuberculosis patients. METHODS: A cross-sectional survey whereby blood sample was ...

  20. Human immunodeficiency virus (HIV) and Epstein-Barr virus (EBV) related lymphomas, pathology view point.

    Science.gov (United States)

    Linke-Serinsöz, Ebru; Fend, Falko; Quintanilla-Martinez, Leticia

    2017-07-01

    The contribution of Epstein Barr virus (EBV) and Kaposi sarcoma herpes virus (KSHV) to the development of specific types of malignant lymphomas occurring in the human immunodeficiency virus (HIV) setting has been extensively studied since the beginning of the HIV epidemic 35 years ago. The introduction of highly active antiretroviral therapies (HAART) in 1996 has changed dramatically the incidence of HIV-related malignancies. Nevertheless, malignant lymphomas continue to be the major group of malignances observed in HIV infected individuals, and the most common cause of cancer related-deaths. Common features of the predominant B-cell lymphomas in the HIV + setting are the frequent plasmacytoid morphology of the neoplastic cells, advanced stage, aggressive disease and frequent extranodal involvement. In this article, we review the evolving concepts and definitions of the various EBV-associated lymphomas in HIV + patients, including diffuse large B-cell lymphoma, Burkitt lymphoma, classical Hodgkin lymphoma, plasmablastic lymphoma and primary effusion lymphoma. The current knowledge regarding the pathogenesis of these malignancies, the interplay between HIV and EBV co-infection in the development of certain HIV related lymphomas, and the emerging paradigm that suggests that HIV may play a direct role in lymphomagenesis are explored as well. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Genomic variability associated with the presence of occult hepatitis B virus in HIV co-infected individuals

    OpenAIRE

    Martin, C. M.; Welge, J.A.; Shire, N. J.; Rouster, S. D.; SHATA, M. T.; Sherman, K E; Blackard, J. T.

    2009-01-01

    Occult hepatitis B virus (O-HBV) infection is characterized by the presence of HBV DNA without detectable hepatitis B surface antigen (HBV DNA+/HBsAg−) in the serum. Although O-HBV is more prevalent during HBV/HIV co-infection, analysis of HBV mutations in co-infected patients is limited. In this preliminary study, HBV PreSurface (PreS) and surface (S) regions were amplified from 33 HIV-positive patient serum samples − 27 chronic HBV (C-HBV) and six O-HBV infections. HBV genotype was determin...

  2. Influenza virus antigenic variation, host antibody production and new approach to control epidemics

    Directory of Open Access Journals (Sweden)

    Deng Yi-Mo

    2009-03-01

    Full Text Available Abstract Influenza is an infectious disease and can lead to life-threatening complications like pneumonia. The disease is caused by three types of RNA viruses called influenza types A, B and C, each consisting of eight negative single-stranded RNA-segments encoding 11 proteins. Current annual vaccines contain two type A strains and one type B strain and are capable of inducing strong antibody responses to both the surface glycoprotein hemagglutinin and the neuraminidase. While these vaccines are protective against vaccine viruses they are not effective against newly emerging viruses that contain antigenic variations known as antigenic drift and shift. In nature, environmental selection pressure generally plays a key role in selecting antigenic changes in the antigen determining spots of hemagglutinin, resulting in changes in the antigenicity of the virus. Recently, a new technology has been developed where influenza-specific IgG+ antibody-secreting plasma cells can be isolated and cloned directly from vaccinated humans and high affinity monoclonal antibodies can be produced within several weeks after vaccination. The new technology holds great promise for the development of effective passive antibody therapy to limit the spread of influenza viruses in a timely manner.

  3. Perspectives on Human Immunodeficiency Virus (HIV) Cure: HIV Persistence in Tissue.

    Science.gov (United States)

    Boritz, Eli A; Douek, Daniel C

    2017-03-15

    The uneven anatomic distribution of cell subsets that harbor human immunodeficiency virus (HIV) during antiretroviral therapy (ART) complicates investigation of the barriers to HIV cure. Here we propose that while previous studies done largely in blood cells have led to important investigations into HIV latency, other important mechanisms of HIV persistence during ART may not be readily apparent in the bloodstream. We specifically consider as an example the question of ongoing HIV replication during ART. We discuss how growing understanding of key anatomic sanctuaries for the virus can inform future experiments aimed at further clarifying this issue. Published by Oxford University Press for the Infectious Diseases Society of America 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  4. Circulation and antigenic drift in human influenza B viruses in SE Asia and Oceania since 2000.

    Science.gov (United States)

    Barr, Ian G; Komadina, Naomi; Durrant, Chris; Sjogren, Helen; Hurt, Aeron C; Shaw, Robert P

    2006-01-01

    During annual influenza epidemics, influenza B viruses frequently co-circulate with influenza A viruses and in some years, such as 2005, large outbreaks have occurred while in other years, the virus virtually disappears. Since 1987 there have been two lineages of influenza B viruses co-circulating in various countries and causing disease in humans. The proportions of these two lineages vary from year to year and country to country. For example, in 2005, the B/Victoria/2/87 lineage was predominant in New Zealand while in Australia the B/Yamagata/16/88 lineage was more common. Antigenic and genetic analysis has revealed gradual movement in the both lineages. Careful monitoring of the two virus lineages is important, as they are antigenically distinct. This is an important consideration for influenza vaccine formulation decisions, as only one influenza B component is traditionally included in the annual trivalent influenza vaccine.

  5. Dengue NS1 Antigen - for Early Detection of Dengue Virus Infection

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    Amol Hartalkar

    2015-08-01

    Full Text Available Objectives: To evaluate the efficacy of NS1 antigen assay for early diagnosis of dengue virus infection in a tertiary care hospital. Methods: This cross sectional study was carried out in department of Medicine from August to December 2013. Total 100 patients with dengue fever were included. Complete blood count, alanine aminotransferase (ALT, aspartate aminotransferase (AST, Dengue NS1 antigen and IgM and IgG antibodies of dengue virus were done in all cases. Results: Of the 100 sera tested, 75% were positive for dengue virus infection based on dengue NS1 antigen, IgM antibody and IgG antibody. Dengue NS1 antigen and IgM, IgG antibody were able to detect dengue virus infection between day 1 to day 8 in 92% of samples, 86.7% of samples and 82.6% of samples respectively. Sixty nine percent (69% were found positive for dengue NS1 antigen, 65% were IgM positive and 62% were IgG positive. Based on the dengue NS1 antigen and IgM antibody combination, 74% were positive for dengue virus infections. Sensitivity of Dengue NS1 antigen was 92.3% and specificity of 74.28% in comparison to IgM antibody. Detection rate increased to 75%, based on the antigen and IgG antibody combination. Sensitivity of dengue NS1 antigen was 90.3% and specificity of 65.8% in comparison to IgG antibody. Conclusion: Dengue NS1 antigen is a useful, sensitive and specific test for early diagnosis of dengue virus infection and it improves diagnostic efficiency in combination with antibody test. Key words: Dengue fever, NS1 antigen. Introduction: Dengue fever (DF is the most common arboviral illness in humans. Each year, an estimated 50-100 million cases of dengue fever and 500,000 cases of dengue hemorrhagic fever occur worldwide, with 30000 deaths (mainly in children. Globally 2.5-3 billion people in approximately 112 tropical and subtropical countries are at risk of dengue.of samples respectively. Sixty nine percent (69% were found positive for dengue NS1 antigen, 65% were Ig

  6. Virus-driven Inflammation Is Associated With the Development of bNAbs in Spontaneous Controllers of HIV.

    Science.gov (United States)

    Dugast, Anne-Sophie; Arnold, Kelly; Lofano, Giuseppe; Moore, Sarah; Hoffner, Michelle; Simek, Melissa; Poignard, Pascal; Seaman, Michael; Suscovich, Todd J; Pereyra, Florencia; Walker, Bruce D; Lauffenburger, Doug; Kwon, Douglas S; Keele, Brandon F; Alter, Galit

    2017-04-15

    Understanding the mechanism(s) by which broadly neutralizing antibodies (bNAbs) emerge naturally following infection is crucial for the development of a protective vaccine against human immunodeficiency virus (HIV). Although previous studies have implicated high viremia and associated immune activation as potential drivers for the development of bNAbs, here we sought to unlink the effect of these 2 parameters by evaluating the key inflammatory predictors of bNAb development in HIV-infected individuals who spontaneously control HIV in the absence of antiretroviral therapy ("controllers"). The breadth of antibody-mediated neutralization against 11 tier 2 or 3 viruses was assessed in 163 clade B spontaneous controllers of HIV. Plasma levels of 17 cytokines were screened in the same set of subjects. The relationship of the inflammatory signature was assessed in the context of viral blips or viral RNA levels in peripheral blood or gastrointestinal biopsies from aviremic controllers (HIV controllers who developed bNAbs. Interestingly, viral load and tissue viremia, but not intermittent viral blips, were associated with these cytokine profiles. However, viral diversity was not significantly associated with increased breadth in controllers. These results suggest that low antigenic diversity in the setting of a unique inflammatory profile associated with antigen persistence may be linked to the evolution of neutralizing antibody breadth.

  7. Antigen-presenting particle technology using inactivated surface-engineered viruses: induction of immune responses against infectious agents

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    Chang Yung-Nien

    2007-05-01

    Full Text Available Abstract Background Developments in cell-based and gene-based therapies are emerging as highly promising areas to complement pharmaceuticals, but present day approaches are too cumbersome and thereby limit their clinical usefulness. These shortcomings result in procedures that are too complex and too costly for large-scale applications. To overcome these shortcomings, we described a protein delivery system that incorporates over-expressed proteins into viral particles that are non-infectious and stable at room temperature. The system relies on the biological process of viral egress to incorporate cellular surface proteins while exiting their host cells during lytic and non-lytic infections. Results We report here the use of non-infectious surface-engineered virion particles to modulate immunity against three infectious disease agents – human immunodeficiency virus type 1 (HIV-1, herpes simplex virus (HSV, and Influenza. Surface-engineering of particles are accomplished by genetic modification of the host cell surface that produces the egress budding viral particle. Human peripheral blood lymphocytes from healthy donors exposed to CD80/B7.1, CD86/B7.2, and/or antiCD3 single-chain antibody surface-engineered non-infectious HIV-1 and HSV-2 particles stimulate T cell proliferation, whereas particles released from non-modified host cells have no T cell stimulatory activity. In addition to T cell proliferation, HIV-based particles specifically suppress HIV-1 replication (both monocytotropic and lymphocytotropic strains 55 to 96% and HSV-based particles specifically induce cross-reactive HSV-1/HSV-2 anti-herpes virus antibody production. Similar surface engineering of influenza-based particles did not modify the intrinsic ability of influenza particles to stimulate T cell proliferation, but did bestow on the engineered particles the ability to induce cross-strain anti-influenza antibody production. Conclusion We propose that non-infectious viral

  8. A Review of Intra- and Extracellular Antigen Delivery Systems for Virus Vaccines of Finfish

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    Hetron Mweemba Munang’andu

    2015-01-01

    Full Text Available Vaccine efficacy in aquaculture has for a long time depended on evaluating relative percent survival and antibody responses after vaccination. However, current advances in vaccine immunology show that the route in which antigens are delivered into cells is deterministic of the type of adaptive immune response evoked by vaccination. Antigens delivered by the intracellular route induce MHC-I restricted CD8+ responses while antigens presented through the extracellular route activate MHC-II restricted CD4+ responses implying that the route of antigen delivery is a conduit to induction of B- or T-cell immune responses. In finfish, different antigen delivery systems have been explored that include live, DNA, inactivated whole virus, fusion protein, virus-like particles, and subunit vaccines although mechanisms linking these delivery systems to protective immunity have not been studied in detail. Hence, in this review we provide a synopsis of different strategies used to administer viral antigens via the intra- or extracellular compartments. Further, we highlight the differences in immune responses induced by antigens processed by the endogenous route compared to exogenously processed antigens. Overall, we anticipate that the synopsis put together in this review will shed insights into limitations and successes of the current vaccination strategies used in finfish vaccinology.

  9. Rationally Designed Influenza Virus Vaccines That Are Antigenically Stable during Growth in Eggs

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    Alfred T. Harding

    2017-06-01

    Full Text Available Influenza virus vaccine production is currently limited by the ability to grow circulating human strains in chicken eggs or in cell culture. To facilitate cost-effective growth, vaccine strains are serially passaged under production conditions, which frequently results in mutations of the major antigenic protein, the viral hemagglutinin (HA. Human vaccination with an antigenically drifted strain is known to contribute to poor vaccine efficacy. To address this problem, we developed a replication-competent influenza A virus (IAV with an artificial genomic organization that allowed the incorporation of two independent and functional HA proteins with different growth requirements onto the same virion. Vaccination with these viruses induced protective immunity against both strains from which the HA proteins were derived, and the magnitude of the response was as high as or higher than vaccination with either of the monovalent parental strains alone. Dual-HA viruses also displayed remarkable antigenic stability; even when using an HA protein known to be highly unstable during growth in eggs, we observed high-titer virus amplification without a single adaptive mutation. Thus, the viral genomic design described in this work can be used to grow influenza virus vaccines to high titers without introducing antigenic mutations.

  10. Antigenic and Molecular Characterization of Avian Influenza A(H9N2) Viruses, Bangladesh

    Science.gov (United States)

    Shanmuganatham, Karthik; Feeroz, Mohammed M.; Jones-Engel, Lisa; Smith, Gavin J.D.; Fourment, Mathieu; Walker, David; McClenaghan, Laura; Alam, S.M. Rabiul; Hasan, M. Kamrul; Seiler, Patrick; Franks, John; Danner, Angie; Barman, Subrata; McKenzie, Pamela; Krauss, Scott; Webby, Richard J.

    2013-01-01

    Human infection with avian influenza A(H9N2) virus was identified in Bangladesh in 2011. Surveillance for influenza viruses in apparently healthy poultry in live-bird markets in Bangladesh during 2008–2011 showed that subtype H9N2 viruses are isolated year-round, whereas highly pathogenic subtype H5N1 viruses are co-isolated with subtype H9N2 primarily during the winter months. Phylogenetic analysis of the subtype H9N2 viruses showed that they are reassortants possessing 3 gene segments related to subtype H7N3; the remaining gene segments were from the subtype H9N2 G1 clade. We detected no reassortment with subtype H5N1 viruses. Serologic analyses of subtype H9N2 viruses from chickens revealed antigenic conservation, whereas analyses of viruses from quail showed antigenic drift. Molecular analysis showed that multiple mammalian-specific mutations have become fixed in the subtype H9N2 viruses, including changes in the hemagglutinin, matrix, and polymerase proteins. Our results indicate that these viruses could mutate to be transmissible from birds to mammals, including humans. PMID:23968540

  11. Mutated epitopes of hepatitis B surface antigen fused to the core antigen of the virus induce antibodies that react with the native surface antigen.

    Science.gov (United States)

    Shiau, A L; Murray, K

    1997-03-01

    Fusion of peptide epitopes to the core antigen (HBcAg) of hepatitis B virus (HBV) enhances their immunogenicity, both quantitatively and qualitatively. In a number of vaccine-induced mutants of HBV, glycine145 of the surface antigen S polypeptide (HBsAg) has been replaced by arginine, resulting in loss of cross-reactivity with antibodies to normal (wild-type) HBsAg. HBcAg fusion proteins carrying the immunodominant epitope of HBsAg, in which glycine145 was replaced by arginine, glutamic acid, or lysine, were produced in Escherichia coli and formed particles that displayed HBc antigenicity and immunogenicity similar to that of HBcAg itself. The fusion proteins also elicited T-cell proliferative responsiveness to HBcAg and HBsAg. Fusions carrying either wild-type or mutated epitopes of HBsAG showed HBs antigenicity in immunoblot analysis and antigen-capture immunoradiometric assay, but both mutant and wild-type derivatives induced antibodies that cross-reacted with wild-type HBsAG. The results emphasise the potential for HBcAg fusion proteins in vaccines by broadening the antibody response in a way that could confer protection against both wild-type and variant form of HBV.

  12. Brugia malayi Antigen (BmA Inhibits HIV-1 Trans-Infection but Neither BmA nor ES-62 Alter HIV-1 Infectivity of DC Induced CD4+ Th-Cells.

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    Emily E I M Mouser

    Full Text Available One of the hallmarks of HIV-1 disease is the association of heightened CD4+ T-cell activation with HIV-1 replication. Parasitic helminths including filarial nematodes have evolved numerous and complex mechanisms to skew, dampen and evade human immune responses suggesting that HIV-1 infection may be modulated in co-infected individuals. Here we studied the effects of two filarial nematode products, adult worm antigen from Brugia malayi (BmA and excretory-secretory product 62 (ES-62 from Acanthocheilonema viteae on HIV-1 infection in vitro. Neither BmA nor ES-62 influenced HIV-1 replication in CD4+ enriched T-cells, with either a CCR5- or CXCR4-using virus. BmA, but not ES-62, had the capacity to bind the C-type lectin dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN thereby inhibiting HIV-1 trans-infection of CD4+ enriched T-cells. As for their effect on DCs, neither BmA nor ES-62 could enhance or inhibit DC maturation as determined by CD83, CD86 and HLA-DR expression, or the production of IL-6, IL-10, IL-12 and TNF-α. As expected, due to the unaltered DC phenotype, no differences were found in CD4+ T helper (Th cell phenotypes induced by DCs treated with either BmA or ES-62. Moreover, the HIV-1 susceptibility of the Th-cell populations induced by BmA or ES-62 exposed DCs was unaffected for both CCR5- and CXCR4-using HIV-1 viruses. In conclusion, although BmA has the potential capacity to interfere with HIV-1 transmission or initial viral dissemination through preventing the virus from interacting with DCs, no differences in the Th-cell polarizing capacity of DCs exposed to BmA or ES-62 were observed. Neither antigenic source demonstrated beneficial or detrimental effects on the HIV-1 susceptibility of CD4+ Th-cells induced by exposed DCs.

  13. An automated HIV-1 Env-pseudotyped virus production for global HIV vaccine trials.

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    Anke Schultz

    Full Text Available BACKGROUND: Infections with HIV still represent a major human health problem worldwide and a vaccine is the only long-term option to fight efficiently against this virus. Standardized assessments of HIV-specific immune responses in vaccine trials are essential for prioritizing vaccine candidates in preclinical and clinical stages of development. With respect to neutralizing antibodies, assays with HIV-1 Env-pseudotyped viruses are a high priority. To cover the increasing demands of HIV pseudoviruses, a complete cell culture and transfection automation system has been developed. METHODOLOGY/PRINCIPAL FINDINGS: The automation system for HIV pseudovirus production comprises a modified Tecan-based Cellerity system. It covers an area of 5×3 meters and includes a robot platform, a cell counting machine, a CO(2 incubator for cell cultivation and a media refrigerator. The processes for cell handling, transfection and pseudovirus production have been implemented according to manual standard operating procedures and are controlled and scheduled autonomously by the system. The system is housed in a biosafety level II cabinet that guarantees protection of personnel, environment and the product. HIV pseudovirus stocks in a scale from 140 ml to 1000 ml have been produced on the automated system. Parallel manual production of HIV pseudoviruses and comparisons (bridging assays confirmed that the automated produced pseudoviruses were of equivalent quality as those produced manually. In addition, the automated method was fully validated according to Good Clinical Laboratory Practice (GCLP guidelines, including the validation parameters accuracy, precision, robustness and specificity. CONCLUSIONS: An automated HIV pseudovirus production system has been successfully established. It allows the high quality production of HIV pseudoviruses under GCLP conditions. In its present form, the installed module enables the production of 1000 ml of virus-containing cell

  14. Human immunodeficiency virus (HIV) infection screening in a dialysis unit.

    Science.gov (United States)

    Chou, Chia-Chi; Sun, Chia-Yi; Wu, Mai-Szu

    2007-01-01

    Human immunodeficiency virus (HIV) screening is a routine for long-term hemodialysis patients because of a high risk for infection. Enzyme-immunoassay (EIA) is a simple tool for screening HIV, but clinically false-positive EIA is a frequent result. Other tests such as Western blot analysis (WB) and HIV DNA and RNA by polymerase chain reaction have better specificity and sensitivity, but they cannot be accessible in many dialysis units. Four hundred and four patients with end stage renal disease on long-term hemodialysis were screened with EIA for HIV antibodies. Repeated EIA was performed if the first test was positive result. WB was used as the confirmatory test. Two persons initially showed a positive EIA pattern among the 404 patients, but nobody had positive WB test result later. The ratio of false-positive EIA results for screening HIV is relatively high in long-term hemodialysis patients. Further tests should be employed to confirm the diagnosis.

  15. Alphavirus replicon DNA expressing HIV antigens is an excellent prime for boosting with recombinant modified vaccinia Ankara (MVA or with HIV gp140 protein antigen.

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    Maria L Knudsen

    Full Text Available Vaccination with DNA is an attractive strategy for induction of pathogen-specific T cells and antibodies. Studies in humans have shown that DNA vaccines are safe, but their immunogenicity needs further improvement. As a step towards this goal, we have previously demonstrated that immunogenicity is increased with the use of an alphavirus DNA-launched replicon (DREP vector compared to conventional DNA vaccines. In this study, we investigated the effect of varying the dose and number of administrations of DREP when given as a prime prior to a heterologous boost with poxvirus vector (MVA and/or HIV gp140 protein formulated in glucopyranosyl lipid A (GLA-AF adjuvant. The DREP and MVA vaccine constructs encoded Env and a Gag-Pol-Nef fusion protein from HIV clade C. One to three administrations of 0.2 μg DREP induced lower HIV-specific T cell and IgG responses than the equivalent number of immunizations with 10 μg DREP. However, the two doses were equally efficient as a priming component in a heterologous prime-boost regimen. The magnitude of immune responses depended on the number of priming immunizations rather than the dose. A single low dose of DREP prior to a heterologous boost resulted in greatly increased immune responses compared to MVA or protein antigen alone, demonstrating that a mere 0.2 μg DREP was sufficient for priming immune responses. Following a DREP prime, T cell responses were expanded greatly by an MVA boost, and IgG responses were also expanded when boosted with protein antigen. When MVA and protein were administered simultaneously following multiple DREP primes, responses were slightly compromised compared to administering them sequentially. In conclusion, we have demonstrated efficient priming of HIV-specific T cell and IgG responses with a low dose of DREP, and shown that the priming effect depends on number of primes administered rather than dose.

  16. [Investigation of a new HIV-1 p24 antigen detection kit based on the enzyme-linked fluorescent immunoassay].

    Science.gov (United States)

    Hayashi, T; Saito, T; Kondo, M; Watanabe, S; Imai, M

    2000-09-01

    We investigated the performance of the new p24 antigen detection kit (VIDAS HIV p24) with the conventional antigen kit (HIV-1 Ag monoclonal; Abbott). The new kit is an enzyme-linked fluorescent immunoassay (ELFA) and all of the assay steps are performed automatically by the VIDAS instrument within 100 minutes. With the seven HIV-1 seroconversion panels, three seroconversions were detected on an average of 6.8 days earlier with ELFA than the conventional EIA kit. ELFA showed negative results for all of the 11 false positive samples by the combined (p24, anti-HIV) detection kit (VIDAS HIV DUO). The results obtained suggest that ELFA are very useful for an earlier diagnosis of HIV infection and re-test for false positive samples by other HIV diagnosis kits.

  17. Reduction of Diagnostic Window by New Fourth-Generation Human Immunodeficiency Virus Screening Assays†

    OpenAIRE

    Weber, Bernard; Mbargane Fall, El Hadji; Berger, Annemarie; Doerr, Hans Wilhelm

    1998-01-01

    In order to reduce the diagnostic window between the time of human immunodeficiency virus (HIV) infection and laboratory diagnosis, new screening enzyme-linked immunosorbent assays (ELISAs) which permit the simultaneous detection of HIV antigen and antibody have been developed. Two fourth-generation assays, HIV DUO (Biomérieux) and HIV Combi (Boehringer Mannheim), for the combined detection of HIV antigen and antibody, were compared with a third-generation assay (HIV-1/HIV-2 3rd Generation Pl...

  18. Transgenic lettuce seedlings carrying hepatitis B virus antigen HBsAg

    OpenAIRE

    Jackson Marcondes; Ekkehard Hansen

    2008-01-01

    The obtainment of transgenic edible plants carrying recombinant antigens is a desired issue in search for economic alternatives viewing vaccine production. Here we report a strategy for genetic transformation of lettuce plants (Lactuca sativa L.) using the surface antigen HBsAg of hepatitis B virus. Transgenic lettuce seedlings were obtained through the application of a regulated balance of plant growth regulators. Genetic transformation process was acquired by cocultivation of cotyledons wit...

  19. Defining Influenza A Virus Hemagglutinin Antigenic Drift by Sequential Monoclonal Antibody Selection

    OpenAIRE

    Das, Suman R.; Hensley, Scott E.; Ince, William L.; Brooke, Christopher B.; Subba, Anju; Delboy, Mark G.; Russ, Gustav; Gibbs, James S.; Bennink, Jack R.; Yewdell, Jonathan W.

    2013-01-01

    Human influenza A virus (IAV) vaccination is limited by “antigenic drift,” rapid antibody-driven escape reflecting amino acid substitutions in the globular domain of hemagglutinin (HA), the viral attachment protein. To better understand drift, we used anti-hemagglutinin monoclonal Abs (mAbs) to sequentially select IAV escape mutants. Twelve selection steps, each resulting in a single amino acid substitution in the hemagglutinin globular domain, were required to eliminate antigenicity defined ...

  20. Human Immunodeficiency Virus (HIV) Research (AIDS)

    Science.gov (United States)

    1993-07-15

    Dermatology Microflora"(comploted) Smith RV22 Retrospective Review Gtter RV44 HIV/ Syphilis Johnson RV44 Propylthiouracil 1aCivito XV40 Chatges-Blood...follows: 1) To identify all HIV positive or HIV exposed pregnant women as early in gestation as possible and obtain blood samples in each trimester...of HZV Infection on the Clinical manifestations and Response to Treatment of Syphilis ’- This protocol had the purpose of defining the risk factors

  1. Reduction of the HIV seroconversion window period and false positive rate by using ADVIA Centaur HIV antigen/antibody combo assay.

    Science.gov (United States)

    Lee, Kyunghoon; Park, Hyung-Doo; Kang, Eun-Suk

    2013-11-01

    Early diagnosis of HIV infection reduces morbidity and mortality. Fourth-generation HIV detection assays are more sensitive because they can detect p24 antigen as well as anti-HIV antibodies. In this study, we evaluated the performance of a new fourth-generation ADVIA Centaur HIV antigen/antibody combo (CHIV) assay (Siemens Healthcare Diagnostics Inc., USA) for early detection of HIV infection and reduction of false positive rate. Four seroconversion panels were included. The third-generation ADVIA Centaur HIV 1/O/2 enhanced (EHIV) assay (Siemens Healthcare Diagnostics Inc., USA) and fourth-generation CHIV assay were used to test each panel for HIV infection. The presence of antigen was confirmed using HIV p24 antigen assay. To evaluate false-positivity and specificity, 54 HIV false-positive and HIV-negative serum samples from 100 hospitalized patients and 600 healthy subjects were included. COMPARED TO THE EHIV ASSAY, THE CHIV ASSAY HAD A SHORTER WINDOW FOR THREE OF THE SEROCONVERSION PANELS: a difference of 10 days and two bleeds in one panel, and 4 days and one bleed in the other two panels. Only 34 of the 54 (63%) samples known to yield false-positive results by EHIV assay had repeatedly yielded reactive results in the CHIV assay. One of the 600 healthy subjects had a false-positive result with the CHIV assay; thus, the specificity was 99.85% (699/700). CHIV accurately determined the reactive results for the HIV-confirmed serum samples from known HIV patients and Korea Food & Drug Administration (KFDA) panels. The new fourth-generation ADVIA Centaur HIV assay is a sensitive and specific assay that shortens the serological window period and allows early diagnosis of HIV infection.

  2. Epstein-Barr virus and human immunodeficiency virus serological responses and viral burdens in HIV-infected patients treated with HAART

    Science.gov (United States)

    O'Sullivan, Cathal E.; Peng, RongSheng; Cole, Kelly Stefano; Montelaro, Ronald C.; Sturgeon, Timothy; Jenson, Hal B.; Ling, Paul D.; Butel, J. S. (Principal Investigator)

    2002-01-01

    Epstein-Barr virus (EBV) associated non-Hodgkin lymphoma is recognized as a complication of human immunodeficiency virus (HIV) infection. Little is known regarding the influence of highly active antiretroviral therapy (HAART) on the biology of EBV in this population. To characterize the EBV- and HIV-specific serological responses together with EBV DNA levels in a cohort of HIV-infected adults treated with HAART, a study was conducted to compare EBV and HIV serologies and EBV DNA copy number (DNAemia) over a 12-month period after the commencement of HAART. All patients were seropositive for EBV at baseline. Approximately 50% of patients had detectable EBV DNA at baseline, and 27/30 had detectable EBV DNA at some point over the follow-up period of 1 year. Changes in EBV DNA copy number over time for any individual were unpredictable. Significant increases in the levels of Epstein-Barr nuclear antigen (EBNA) and Epstein-Barr early antigen (EA) antibodies were demonstrated in the 17 patients who had a good response to HAART. Of 29 patients with paired samples tested, four-fold or greater increases in titers were detected for EA in 12/29 (41%), for EBNA in 7/29 (24%), for VCA-IgG in 4/29 (14%); four-fold decreases in titers were detected in 2/29 (7%) for EA and 12/29 (41%) for EBNA. A significant decline in the titer of anti-HIV antibodies was also demonstrated. It was concluded that patients with advanced HIV infection who respond to HAART have an increase in their EBV specific antibodies and a decrease in their HIV-specific antibodies. For the cohort overall, there was a transient increase in EBV DNA levels that had declined by 12 months. Copyright 2002 Wiley-Liss, Inc.

  3. Sterilizing immunity to influenza virus infection requires local antigen-specific T cell response in the lungs

    OpenAIRE

    Avijit Dutta; Ching-Tai Huang; Chun-Yen Lin; Tse-Ching Chen; Yung-Chang Lin; Chia-Shiang Chang; Yueh-Chia He

    2016-01-01

    Sterilizing immunity is a unique immune status, which prevents effective virus infection into the host. It is different from the immunity that allows infection but with subsequent successful eradication of the virus. Pre-infection induces sterilizing immunity to homologous influenza virus challenge in ferret. In our antigen-specific experimental system, mice pre-infected with PR8 influenza virus through nasal route are likewise resistant to reinfection of the same strain of virus. The virus i...

  4. Reducing V3 Antigenicity and Immunogenicity on Soluble, Native-Like HIV-1 Env SOSIP Trimers.

    Science.gov (United States)

    Ringe, Rajesh P; Ozorowski, Gabriel; Rantalainen, Kimmo; Struwe, Weston B; Matthews, Katie; Torres, Jonathan L; Yasmeen, Anila; Cottrell, Christopher A; Ketas, Thomas J; LaBranche, Celia C; Montefiori, David C; Cupo, Albert; Crispin, Max; Wilson, Ian A; Ward, Andrew B; Sanders, Rogier W; Klasse, P J; Moore, John P

    2017-08-01

    Native-like trimers of the SOSIP design are being developed as immunogens in human immunodeficiency virus type 1 (HIV-1) vaccine development programs. These trimers display the epitopes for multiple broadly neutralizing antibodies (bNAbs) but can also expose binding sites for some types of nonneutralizing antibodies (non-NAbs). Among the latter are epitopes in the gp120 V3 region that are highly immunogenic when SOSIP trimers are evaluated in animal models. It is presently uncertain whether antibodies against V3 can interfere with the induction of NAbs, but there are good arguments in favor of suppressing such "off-target" immune responses. Accordingly, we have assessed how to minimize the exposure of V3 non-NAb epitopes and thereby reduce their immunogenicity by introducing N-glycans within the V3 region of BG505 SOSIP trimers. We found that inserting glycans at positions 306 and 314 (termed M1 and M7) markedly reduced V3 antigenicity while improving the presentation of trimer apex bNAb epitopes. Both added glycans were shown to be predominantly of the Man6GlcNAc2 form. The additional introduction of the E64K ground-state stabilizing substitution markedly reduced or ablated soluble CD4 (sCD4) induction of non-NAb epitopes in V3 and/or associated with the coreceptor binding site. When a V3 glycan- and E64K-modified trimer variant, BG505 SOSIP.664-E64K.M1M7, was tested in rabbits, V3 immunogenicity was eliminated while the autologous NAb response was unchanged.IMPORTANCE Trimeric proteins are being developed for future HIV-1 vaccine trials in humans, with the goal of eliciting broadly active neutralizing antibodies (NAbs) that are active against a wide variety of circulating strains. In animal models, the present generation of native-like trimer immunogens, exemplified by the BG505 SOSIP.664 construct, induces narrow-specificity antibodies against the neutralization-resistant (tier-2), sequence-matched virus and more broadly active antibodies against sequence

  5. The global antigenic diversity of swine influenza A viruses

    NARCIS (Netherlands)

    N.S. Lewis (Nicola); C.A. Russell (Colin); P. Langat (Pinky); T.K. Anderson (Tavis); K. Berger (Kathryn); F. Bielejec (Filip); D.F. Burke (David); G. Dudas (Gytis); J.M. Fonville (Judith); R.A.M. Fouchier (Ron); P. Kellam (Paul); B.F. Koel (Björn); P. Lemey (Philippe); T. Nguyen (Tung); B. Nuansrichy (Bundit); J.S. Malik Peiris; T. Saito (Takehiko); G. Simon (Gaelle); E. Skepner (Eugene); N. Takemae (Nobuhiro); R.J. Webby (Richard J.); K. van Reeth; S.M. Brookes (Sharon M.); L. Larsen (Lars); S.J. Watson (Simon J.); I.H. Brown (Ian); A.L. Vincent (Amy L.); S. Reid (Scott); M.A. Garcia (Montserrat Auero); T.C. Harder (Timm); E. Foni (Emanuela); I. Markowska-Daniel (Iwona)

    2016-01-01

    textabstractSwine influenza presents a substantial disease burden for pig populations worldwide and poses a potential pandemic threat to humans. There is considerable diversity in both H1 and H3 influenza viruses circulating in swine due to the frequent introductions of viruses from humans and birds

  6. Seroprevalence of Human Immunodifficiency Virus (HIV) amongst ...

    African Journals Online (AJOL)

    A cross sectional period prevalence study was carried out amongst inmates of Convict Prison, Kaduna Nigeria to determine their HIV status and provide baseline data. Out of the 100 samples collected, 12 (12 %) were positive for HIV with the highest proportion (41.7 %) occurring in the 20-29 yrs age bracket and lowest ...

  7. Seroprevalence of Human Immunodeficiency Virus (HIV) and ...

    African Journals Online (AJOL)

    Serological screening for Anti-HIV antibodies was done using the Immunocomb ll HIV 1 & 2 Bispot test (Orgenics, Israel), while detection of HBsAg was based on the latex agglutination reaction using the Hepatitis B reagent kit manufactured by Quimica Clinica Aplicada, Spain. Four (3.9%) and 11 (10.6%) of the donors ...

  8. Epstein-Barr virus early antigen diffuse (EBV-EA/D)-directed immunoglobulin A antibodies in systemic lupus erythematosus patients

    DEFF Research Database (Denmark)

    Draborg, A H; Jørgensen, J M; Müller, H

    2012-01-01

    We sought to determine whether the serological response towards lytic cycle antigens of Epstein-Barr virus (EBV) is altered in systemic lupus erythematosus (SLE) patients.......We sought to determine whether the serological response towards lytic cycle antigens of Epstein-Barr virus (EBV) is altered in systemic lupus erythematosus (SLE) patients....

  9. Coinfection with Hepatitis B and C Viruses among HIV Positive ...

    African Journals Online (AJOL)

    Background: Hepatitis B and C viruses coinfection in HIV positive pregnant women is a common public health problem and recognized worldwide. The consequences of this problem in our poor resource setting with the risk of mother to child transmission is obvious with increased morbidity and mortality in our environment.

  10. Awareness of Human Immunodeficiency Virus (HIV) infection among ...

    African Journals Online (AJOL)

    Objective: To determine the level of awareness of Human Immunodeficiency Virus (HIV) infection among antenatal clients in Nnewi Nigeria. Subjects and Methods: A cross sectional descriptive study of six hundred consecutive antenatal clients attending the Nnamdi Azikiwe University Teaching Hospital and five private ...

  11. Epidemiology of hepatitis C virus in HIV-infected patients

    DEFF Research Database (Denmark)

    Peters, Lars; Klein, Marina B

    2015-01-01

    PURPOSE OF REVIEW: This review will give an update on the prevalence of HIV/hepatitis C virus (HCV) coinfection, and describe recent trends in all-cause and cause-specific mortality. The focus is mainly on patients followed in clinics in high-income countries and their heterogeneity in terms...

  12. Pregnancy and transmission of Human Immunodefiency Virus (HIV ...

    African Journals Online (AJOL)

    Conclusion: The incidence of HIV transmission to the male uninfected partner in a serodiscodant setting in Jos during pregnancy is low but its occurrence in this study suggests the need to re-test the seronegative male partners after every pregnancy. Keywords: pregnancy, human immunodeficiency virus, serodiscordance, ...

  13. Hepatitis B, C and Human Immunodeficiency Virus (HIV) Co ...

    African Journals Online (AJOL)

    TNHJOURNALPH

    Hepatitis B, C and Human Immunodeficiency Virus (HIV). Co-infection in Nigerian Children with Sickle Cell Anaemia. Type of Article:CSWI. 1Lucy Eberechukwu Yaguo Ide, 2Seye Babatunde. Departments of 1Paediatrics And Child ... of haemolytic anemia and one of the most common in our society.1 It is a major cause of.

  14. Prevalence Of Hepatitis B Virus Among Hiv Positive Patients Attending Specialist Hospital Sokoto, Nigeria

    Directory of Open Access Journals (Sweden)

    B Aliyu

    2013-12-01

    Full Text Available Prevalence of hepatitis B virus infection among HIV patients attending Sokoto specialist Hospital, Sokoto state, Nigeria was carried out between June and July, 2012, using Diaspot HbsAg kit (preliminary test and Biorex Diagnostic ELISA kit (Confirmatory test. Demographic data, clinical characteristics and laboratory results (Questionnaire, CD4 counts and HBsAg were analyzed. Out of 140 HIV patients tested for hepatitis B surface Antigen (HBsAg only 19 individuals were found positive given the prevalence rate of 13.6% (19/140 among HIV patients. The statistical analysis has shown that there was no observable statistical significant difference between demographic data, clinical characteristics and risk factors with respect to HBV infection. Two of the 140 HIV patients were in the chronic stage of the infection giving a prevalence of 1.43% and two of the patients were at the acute stage of the infection with a percentage prevalence of 1.43% while the remaining fifteen patients were in the active stage of the infection. There was no statistically significant relationship between the mean CD4 counts (428cells/μl of blood in HIV monoinfected patients and the mean CD4 counts (391.1579cells/μl of blood in HBV/HIV co-infected individuals (t=22.1351,df=1,p-value=0.02874,95 percent confidence interval: 174.435 – 644.5648, mean=409.5. Therefore, HIV patients should be screened for HBV during their clinical visit in order to inform clinical management, also adequate care and support programs should be organized to help people living with both infections. International Journal of Environment, Volume-2, Issue-1, Sep-Nov 2013, Pages 37-44 DOI: http://dx.doi.org/10.3126/ije.v2i1.9206

  15. Plant Virus Particles Carrying Tumour Antigen Activate TLR7 and Induce High Levels of Protective Antibody

    OpenAIRE

    Jantipa Jobsri; Alex Allen; Deepa Rajagopal; Michael Shipton; Kostya Kanyuka; Lomonossoff, George P.; Christian Ottensmeier; Diebold, Sandra S.; Stevenson, Freda K.; Natalia Savelyeva

    2015-01-01

    Induction of potent antibody is the goal of many vaccines targeted against infections or cancer. Modern vaccine designs that use virus-like particles (VLP) have shown efficacy for prophylactic vaccination against virus-associated cancer in the clinic. Here we used plant viral particles (PVP), which are structurally analogous to VLP, coupled to a weak idiotypic (Id) tumour antigen, as a conjugate vaccine to induce antibody against a murine B-cell malignancy. The Id-PVP vaccine incorporates a n...

  16. Multiple oncogenic viruses identified in Ocular surface squamous neoplasia in HIV-1 patients

    Directory of Open Access Journals (Sweden)

    Bisson Gregory

    2010-03-01

    Full Text Available Abstract Background Ocular surface squamous neoplasia (OSSN is a rare cancer that has increased in incidence with the HIV pandemic in Africa. The underlying cause of this cancer in HIV-infected patients from Botswana is not well defined. Results Tissues were obtained from 28 OSSN and 8 pterygia patients. The tissues analyzed from OSSN patients were 83% positive for EBV, 75% were HPV positive, 70% were KSHV positive, 75% were HSV-1/2 positive, and 61% were CMV positive by PCR. Tissues from pterygium patients were 88% positive for EBV, 75% were HPV positive, 50% were KSHV positive, and 60% were CMV positive. None of the patients were JC or BK positive. In situ hybridization and immunohistochemistry analyses further identified HPV, EBV, and KSHV in a subset of the tissue samples. Conclusion We identified the known oncogenic viruses HPV, KSHV, and EBV in OSSN and pterygia tissues. The presence of these tumor viruses in OSSN suggests that they may contribute to the development of this malignancy in the HIV population. Further studies are necessary to characterize the molecular mechanisms associated with viral antigens and their potential role in the development of OSSN.

  17. Features of Recently Transmitted HIV-1 Clade C Viruses that Impact Antibody Recognition: Implications for Active and Passive Immunization.

    Science.gov (United States)

    Rademeyer, Cecilia; Korber, Bette; Seaman, Michael S; Giorgi, Elena E; Thebus, Ruwayhida; Robles, Alexander; Sheward, Daniel J; Wagh, Kshitij; Garrity, Jetta; Carey, Brittany R; Gao, Hongmei; Greene, Kelli M; Tang, Haili; Bandawe, Gama P; Marais, Jinny C; Diphoko, Thabo E; Hraber, Peter; Tumba, Nancy; Moore, Penny L; Gray, Glenda E; Kublin, James; McElrath, M Juliana; Vermeulen, Marion; Middelkoop, Keren; Bekker, Linda-Gail; Hoelscher, Michael; Maboko, Leonard; Makhema, Joseph; Robb, Merlin L; Abdool Karim, Salim; Abdool Karim, Quarraisha; Kim, Jerome H; Hahn, Beatrice H; Gao, Feng; Swanstrom, Ronald; Morris, Lynn; Montefiori, David C; Williamson, Carolyn

    2016-07-01

    -seroconversion viruses and evidence of antigenic drift highlights the value of using panels of very recently transmitted viruses and suggests that interventions may need to be modified over time to track the changing epidemic. Furthermore, high divergence such as that observed in the older clade C epidemic in southern Africa may impact vaccine efficacy, although the correlates of infection risk are yet to be defined in the clade C setting. Findings from this study of acute/early clade C viruses will aid vaccine development, and enable identification of new broad and potent antibodies to combat the HIV-1 C-clade epidemic in southern Africa.

  18. Features of Recently Transmitted HIV-1 Clade C Viruses that Impact Antibody Recognition: Implications for Active and Passive Immunization.

    Directory of Open Access Journals (Sweden)

    Cecilia Rademeyer

    2016-07-01

    pre-seroconversion viruses and evidence of antigenic drift highlights the value of using panels of very recently transmitted viruses and suggests that interventions may need to be modified over time to track the changing epidemic. Furthermore, high divergence such as that observed in the older clade C epidemic in southern Africa may impact vaccine efficacy, although the correlates of infection risk are yet to be defined in the clade C setting. Findings from this study of acute/early clade C viruses will aid vaccine development, and enable identification of new broad and potent antibodies to combat the HIV-1 C-clade epidemic in southern Africa.

  19. Lymphocyte proliferation to mycobacterial antigens is detectable across a spectrum of HIV-associated tuberculosis

    Directory of Open Access Journals (Sweden)

    Bakari Muhammad

    2009-02-01

    Full Text Available Abstract Background Identifying novel TB diagnostics is a major public health priority. We explored the diagnostic characteristics of antimycobacterial lymphocyte proliferation assays (LPA in HIV-infected subjects with latent or active TB. Methods HIV-infected subjects with bacille Calmette Guérin (BCG scars and CD4 counts ≥ 200 cells/mm3 entering a TB booster vaccine trial in Tanzania had baseline in vivo and in vitro immune tests performed: tuberculin skin tests (TST, LPA and five day assays of interferon gamma (IFN-γ release. Assay antigens were early secreted antigenic target 6 (ESAT-6, antigen 85 (Ag85, and Mycobacterium tuberculosis whole cell lysate (WCL. Subjects were screened for active TB at enrollment by history, exam, sputum smear and culture. We compared antimycobacterial immune responses between subjects with and without latent or active TB at enrollment. Results Among 1885 subjects screened, 635 had latent TB and 13 had active TB. Subjects with latent TB were more likely than subjects without TB to have LPA responses to ESAT-6 (13.2% vs. 5.5%, P Conclusion Lymphoproliferative responses to mycobacteria are detectable during HIV-associated active TB, and are less sensitive but more specific than TST. Trial registration ClinicalTrials.gov Identifier NCT00052195.

  20. Functional discrepancies in HIV-specific CD8+ T-lymphocyte populations are related to plasma virus load.

    Science.gov (United States)

    Oxenius, Annetie; Sewell, Andrew K; Dawson, Sara J; Günthard, Huldrych F; Fischer, Marek; Gillespie, Geraldine M; Rowland-Jones, Sarah L; Fagard, Catherine; Hirschel, Bernard; Phillips, Rodney E; Price, David A

    2002-11-01

    The potent ability of current antiretroviral drug regimens to control human immunodeficiency Virus-1 (HIV-1) replication, in conjunction with the clinical practice of structured therapeutic interruptions, provides a system in which virus levels are manipulated during a persistent infection in humans. Here, we exploit this system to examine the impact of variable plasma virus load (pVL) on the functionality of HIV-specific CD8+ T-lymphocyte populations. Using both ELISpot methodology and intracellular cytokine staining for interferon (IFN)-gamma to assess functional status, together with fluorochrome-labeled peptide-major histocompatibility complex (pMHC) class I tetramer analysis to detect the physical presence of CD8+ T lymphocytes expressing cognate T-cell receptors (TCRs), we observed that the proportion of HIV-specific CD8+ T lymphocytes capable of mounting an effector response to antigen challenge directly ex vivo is related to the kinetics of virus exposure. Specifically, (a) after prolonged suppression of pVL with antiretroviral therapy (ART), physical and functional measures of HIV-specific CD8+ T-lymphocyte frequencies approximated; and (b) the percentage of functionally responsive cells in the HIV-specific CD8+ T lymphocyte populations declined substantially when therapy was discontinued and pVL recrudesced in the same patients. These results corroborate and extend observations in animal models that describe nonresponsive CD8+ T lymphocytes in the presence of high levels of antigen load and have implications for the interpretation of quantitative data generated by methods that rely on functional readouts.

  1. A casein-kinase-2-related protein kinase is tightly associated with the large T antigen of simian virus 40

    DEFF Research Database (Denmark)

    Götz, C; Koenig, M G; Issinger, O G

    1995-01-01

    The simian virus 40 (SV40) large T antigen is a multifunctional protein involved in SV40 cell transformation and lytic virus infection. Some of its activities are regulated by interaction with cellular proteins and/or by phosphorylation of T antigen by various protein kinases. In this study, we...... of T antigen by the associated kinase is reduced whereas a p34cdc2-kinase-specific peptide has no influence. In addition, the T-antigen-associated protein kinase can use GTP and ATP as phosphate donors. These properties together with the observation that immunopurified T antigen can be phosphorylated...

  2. Ultrasensitive detection of HIV-1 p24 antigen by a hybrid nanomechanical-optoplasmonic platform with potential for detecting HIV-1 at first week after infection.

    Science.gov (United States)

    Kosaka, Priscila M; Pini, Valerio; Calleja, Montserrat; Tamayo, Javier

    2017-01-01

    Early detection of HIV infection is the best way to prevent spread of the disease and to improve the efficiency of the antiretroviral therapy. Nucleic acid amplification tests (NAAT) have become the gold-standard for detecting low-concentrations of the virus in blood. However, these methods are technically demanding and cost-prohibitive in developing countries. Immunoassays are more affordable and can be more easily adapted for point-of-care diagnosis. However, the sensitivity so far of these methods has been too low. We here report the development of a sandwich immunoassay that combines nanomechanical and optoplasmonic transduction methods for detecting the HIV-1 capsid antigen p24 in human serum. The immunoreactions take place on the surface of a compliant microcantilever where gold nanoparticles are used as both mechanical and plasmonic labels. The microcantilever acts as both a mechanical resonator and an optical cavity for the transduction of the mechanical and plasmonic signals. The limit of detection of the immunoassay is 10-17 g/mL that is equivalent to one virion in 10 mL of plasma. This is 5 orders of magnitude better than last generation of approved immunoassays and 2 orders of magnitude better than NAAT. This technology meets the demands to be produced en masse at low cost and the capability for miniaturization to be used at the point-of-care.

  3. Rabies. virus antigen in the brain of apparently healthy slaughtered ...

    African Journals Online (AJOL)

    %) of the 14 positive by both FAT and MIT were also positive by MEN. Probably, adaptation of some strains of rabies virus to dogs has evolved manifested by inapparent infection. The public health implications of these findings are discussed.

  4. Changed epitopes drive the antigenic drift for influenza A (H3N2 viruses

    Directory of Open Access Journals (Sweden)

    Yang Jinn-Moon

    2011-02-01

    Full Text Available Abstract Background In circulating influenza viruses, gradually accumulated mutations on the glycoprotein hemagglutinin (HA, which interacts with infectivity-neutralizing antibodies, lead to the escape of immune system (called antigenic drift. The antibody recognition is highly correlated to the conformation change on the antigenic sites (epitopes, which locate on HA surface. To quantify a changed epitope for escaping from neutralizing antibodies is the basis for the antigenic drift and vaccine development. Results We have developed an epitope-based method to identify the antigenic drift of influenza A utilizing the conformation changes on epitopes. A changed epitope, an antigenic site on HA with an accumulated conformation change to escape from neutralizing antibody, can be considered as a "key feature" for representing the antigenic drift. According to hemagglutination inhibition (HI assays and HA/antibody complex structures, we statistically measured the conformation change of an epitope by considering the number of critical position mutations with high genetic diversity and antigenic scores. Experimental results show that two critical position mutations can induce the conformation change of an epitope to escape from the antibody recognition. Among five epitopes of HA, epitopes A and B, which are near to the receptor binding site, play a key role for neutralizing antibodies. In addition, two changed epitopes often drive the antigenic drift and can explain the selections of 24 WHO vaccine strains. Conclusions Our method is able to quantify the changed epitopes on HA for predicting the antigenic variants and providing biological insights to the vaccine updates. We believe that our method is robust and useful for studying influenza virus evolution and vaccine development.

  5. Immunogenicity of a chimeric hepatitis A virus (HAV) carrying the HIV gp41 epitope 2F5.

    Science.gov (United States)

    Kusov, Yuri Y; Zamjatina, Natalja A; Poleschuk, Valentina F; Michailov, Michail I; Morace, Graziella; Eberle, Josef; Gauss-Müller, Verena

    2007-02-01

    Its stable particle structure combined with its high immunogenicity makes the hepatitis A virus (HAV) a perfect carrier to expose foreign epitopes to the host immune system. In an earlier report [Beneduce, F., Kusov, Y., Klinger, M., Gauss-Müller, V., Morace, G., 2002. Chimeric hepatitis A virus particles presenting a foreign epitope (HIV gp41) at their surface. Antiviral Res. 55, 369-377] chimeric virus-like particles (HAV-gp41) were described that carried at their surface the dominant gp41 epitope 2F5 (2F5e) of the human immunodeficiency virus HIV-1. Extending this work, we now report that chimeric virus HAV-gp41 replicates in HAV-susceptible cells as well as in non-human primates. Infected marmosets developed both an anti-HAV and anti-2F5 epitope immune response. Furthermore, an HIV-neutralizing antibody response was elicited in guinea pigs immunized with HAV-gp41 chimeric particles. The results demonstrate that the replication-competent chimeric HAV-gp41 can serve as either a live or a subunit vaccine for eliciting of antibodies directed against a foreign antigenic epitope.

  6. Enteric viruses in HIV-1 seropositive and HIV-1 seronegative children with diarrheal diseases in Brazil

    Science.gov (United States)

    Rocha, Monica Simões; Fumian, Tulio Machado; Maranhão, Adriana Gonçalves; de Assis, Rosane Maria; Xavier, Maria da Penha Trindade Pinheiro; Rocha, Myrna Santos; Miagostovich, Marize Pereira; Leite, José Paulo Gagliardi; Volotão, Eduardo de Mello

    2017-01-01

    Diarrheal diseases (DD) have distinct etiological profiles in immune-deficient and immune-competent patients. This study compares detection rates, genotype distribution and viral loads of different enteric viral agents in HIV-1 seropositive (n = 200) and HIV-1 seronegative (n = 125) children hospitalized with DD in Rio de Janeiro, Brazil. Except for group A rotavirus (RVA), which were detected through enzyme immunoassay, the other enteric viruses (norovirus [NoV], astrovirus [HAstV], adenovirus [HAdV] and bocavirus [HBoV]) were detected through PCR or RT-PCR. A quantitative PCR was performed for RVA, NoV, HAstV, HAdV and HBoV. Infections with NoV (19% vs. 9.6%; p<0.001), HBoV (14% vs. 7.2%; p = 0.042) and HAdV (30.5% vs. 14.4%; p<0.001) were significantly more frequent among HIV-1 seropositive children. RVA was significantly less frequent among HIV-1 seropositive patients (6.5% vs. 20%; p<0.001). Similarly, frequency of infection with HAstV was lower among HIV-1 seropositive children (5.5% vs. 12.8%; p = 0.018). Among HIV-1 seropositive children 33 (16.5%) had co-infections, including three enteric viruses, such as NoV, HBoV and HAdV (n = 2) and NoV, HAstV and HAdV (n = 2). The frequency of infection with more than one virus was 17 (13.6%) in the HIV-1 negative group, triple infection (NoV + HAstV + HBoV) being observed in only one patient. The median viral load of HAstV in feces was significantly higher among HIV-1 positive children compared to HIV-1 negative children. Concerning children infected with RVA, NoV, HBoV and HAdV, no statistically significant differences were observed in the medians of viral loads in feces, comparing HIV-1 seropositive and HIV-1 seronegative children. Similar detection rates were observed for RVA, HAstV and HAdV, whilst NoV and HBoV were significantly more prevalent among children with CD4+ T lymphocyte count below 200 cells/mm3. Enteric viruses should be considered an important cause of DD in HIV-1 seropositive children, along with

  7. Enteric viruses in HIV-1 seropositive and HIV-1 seronegative children with diarrheal diseases in Brazil.

    Directory of Open Access Journals (Sweden)

    Silvana Augusta Rodrigues Portes

    Full Text Available Diarrheal diseases (DD have distinct etiological profiles in immune-deficient and immune-competent patients. This study compares detection rates, genotype distribution and viral loads of different enteric viral agents in HIV-1 seropositive (n = 200 and HIV-1 seronegative (n = 125 children hospitalized with DD in Rio de Janeiro, Brazil. Except for group A rotavirus (RVA, which were detected through enzyme immunoassay, the other enteric viruses (norovirus [NoV], astrovirus [HAstV], adenovirus [HAdV] and bocavirus [HBoV] were detected through PCR or RT-PCR. A quantitative PCR was performed for RVA, NoV, HAstV, HAdV and HBoV. Infections with NoV (19% vs. 9.6%; p<0.001, HBoV (14% vs. 7.2%; p = 0.042 and HAdV (30.5% vs. 14.4%; p<0.001 were significantly more frequent among HIV-1 seropositive children. RVA was significantly less frequent among HIV-1 seropositive patients (6.5% vs. 20%; p<0.001. Similarly, frequency of infection with HAstV was lower among HIV-1 seropositive children (5.5% vs. 12.8%; p = 0.018. Among HIV-1 seropositive children 33 (16.5% had co-infections, including three enteric viruses, such as NoV, HBoV and HAdV (n = 2 and NoV, HAstV and HAdV (n = 2. The frequency of infection with more than one virus was 17 (13.6% in the HIV-1 negative group, triple infection (NoV + HAstV + HBoV being observed in only one patient. The median viral load of HAstV in feces was significantly higher among HIV-1 positive children compared to HIV-1 negative children. Concerning children infected with RVA, NoV, HBoV and HAdV, no statistically significant differences were observed in the medians of viral loads in feces, comparing HIV-1 seropositive and HIV-1 seronegative children. Similar detection rates were observed for RVA, HAstV and HAdV, whilst NoV and HBoV were significantly more prevalent among children with CD4+ T lymphocyte count below 200 cells/mm3. Enteric viruses should be considered an important cause of DD in HIV-1 seropositive children, along

  8. Hepatitis B virus surface antigen and antibody markers in children at ...

    African Journals Online (AJOL)

    Hepatitis B virus surface antigen and antibody markers in children at a major paediatric hospital after the pentavalent DTP-HBV-Hib vaccination. ... Ghana Medical Journal ... Abstract. Objectives: The knowledge about outcomes of infant vaccination against HBV infections using the DPT-HepB-Hib vaccine in Ghana is limited.

  9. Both conventional and interferon killer dendritic cells have antigen-presenting capacity during influenza virus infection

    NARCIS (Netherlands)

    C.H. Geurts van Kessel (Corine); I.M. Bergen (Ingrid); F. Muskens (Femke); L. Boon (Louis); H.C. Hoogsteden (Henk); A.D.M.E. Osterhaus (Albert); G.F. Rimmelzwaan (Guus); B.N.M. Lambrecht (Bart)

    2009-01-01

    textabstractNatural killer cells are innate effector cells known for their potential to produce interferon-γ and kill tumour and virus-infected cells. Recently, B220+CD11cintNK1.1+ NK cells were found to also have antigen-presenting capacity like dendritic cells (DC), hence their name

  10. Surface antigen-negative hepatitis B virus infection in Dutch blood donors

    NARCIS (Netherlands)

    Lieshout-Krikke, R. W.; Molenaar-de Backer, M. W. A.; van Swieten, P.; Zaaijer, H. L.

    2014-01-01

    Hepatitis B virus (HBV) surface antigen (HBsAg) is a reliable marker for HBV infection, but HBsAg-negative forms of HBV infection occur. The introduction of HBV DNA screening of Dutch blood donors, which were not preselected for absence of HBV core antibodies, enabled the characterization of

  11. Analysis of H7 avian influenza viruses by antigenic cartography and correlation to protection by vaccination

    Science.gov (United States)

    The H7 hemagglutinin subtype one of the most common subtypes of avian influenza virus (AIV) in poultry world wide and since it has the potential to become highly pathogenic it is among the priority subtypes for vaccination. Selection of the optimal vaccine seed strains may now be aided by antigenic...

  12. Autologous HIV-1 neutralizing antibodies: emergence of neutralization-resistant escape virus and subsequent development of escape virus neutralizing antibodies

    DEFF Research Database (Denmark)

    Arendrup, M; Nielsen, C; Hansen, J E

    1992-01-01

    of neutralizing antibodies to the primary virus isolates was detected 13-45 weeks after seroconversion. Emergence of escape virus with reduced sensitivity to neutralization by autologous sera was demonstrated. The patients subsequently developed neutralizing antibodies against the escape virus but after a delay...... escape virus may be part of the explanation of the apparent failure of the immune system to control HIV infection....

  13. Development of envelope protein antigens to serologically differentiate Zika from dengue virus infection.

    Science.gov (United States)

    Premkumar, Lakshmanane; Collins, Matthew; Graham, Stephen; Liou, Guei-Jiun Alice; Lopez, Cesar A; Jadi, Ramesh; Balmaseda, Angel; Brackbill, James A; Dietze, Reynaldo; Camacho, Erwin; De Silva, Aruna D; Giuberti, Camila; Dos Reis, Helena Lucia; Singh, Tulika; Heimsath, Holly; Weiskopf, Daniela; Sette, Alessandro; Osorio, Jorge E; Permar, Sallie R; Miley, Michel J; Lazear, Helen M; Harris, Eva; de Silva, Aravinda M

    2017-12-20

    Zika virus (ZIKV) is an emerging flavivirus that can cause birth defects and neurologic complications. Molecular tests are effective in diagnosing acute ZIKV infection, although the majority of infections produce no symptoms at all or present after the narrow window in which molecular diagnostics are dependable. Serology is a reliable method for detecting infections after the viremic period; however, most serological assays have limited specificity due to cross-reactive antibodies elicited by flavivirus infections. Since ZIKV and dengue virus (DENV) widely co-circulate, distinguishing ZIKV from DENV infection is particularly important for diagnosing individual cases or surveillance to coordinate public health response. Flaviviruses also elicit type-specific antibodies directed to non-cross-reactive epitopes of the infecting virus; such epitopes are attractive targets for designing antigens to develop serologic tests with greater specificity. Guided by comparative epitope modeling of ZIKV envelope protein, we designed two recombinant antigens displaying unique antigenic regions on domain I (Z-EDI) and domain III (Z-EDIII) of ZIKV envelope protein. Both Z-EDI and Z-EDIII antigens consistently detected ZIKV-specific IgG in ZIKV-immune sera but not cross-reactive IgG in DENV-immune sera in late convalescence (>12 weeks post-infection). In contrast, during early convalescence (2-12 weeks post-infection), secondary DENV-immune sera and some primary DENV-immune sera cross-reacted with Z-EDI and Z-EDIII antigens. Analysis of sequential samples from DENV-immune individuals demonstrated that Z-EDIII cross-reactivity peaked in the early convalescence and steeply declined over time. The Z-EDIII antigen has much potential as a diagnostic antigen for population level surveillance and for detecting past infections in patients. Copyright © 2017 American Society for Microbiology.

  14. [Hematological changes associated with human immunodeficiency virus (HIV-1) infection].

    Science.gov (United States)

    Møller, T; Hasselbalch, H C

    1993-05-10

    Infection with human immunodeficiency virus type 1 (HIV-1) primarily involves a subgroup of T-lymphocytic cells, but other cell types are also invaded by the virus, including cell lines within the haematopoietic system. Together with infectious, inflammatory and neoplasic processes, invasion of haematopoietic tissue explains the haematological alterations which are seen during the course of infection with HIV-1. Anaemia develops in the large proportion of patients. Thrombocytopenia frequently occurs during the course of the disease, but may be seen in some patients already at the time of diagnosis, where the condition may be misdiagnosed as "idiopathic" thrombocytopenic purpura. Neutropenia is seen in all disease stages, but is most severe in patients with advanced disease. Bone marrow changes include varying degrees of dysplasia in one or more cell lines, which in some patients may mimic a myelodysplastic syndrome. The number of plasma cells is always increased. In many patients the bone marrow stroma exhibits an increased amount of reticular fibres. HIV-1 infection is associated with an increased risk of non-Hodgkin malignant lymphoma. Acute myelogenous leukaemia and myelomatosis have been described in patients with advanced disease. Treatment of the above mentioned haematological abnormalities aims primarily at reducing replication of HIV-1, thereby diminishing suppression of haematopoiesis by the virus infection, and at controlling the opportunistic infections during the course of the disease. Specific antiviral therapy (AZT) is most successful in correcting thrombocytopenia. The possibility of bone marrow suppression mediated by a toxic drug effect should always be considered in this patient group.

  15. Production of immunologically active surface antigens of hepatitis B virus by Escherichia coli.

    Science.gov (United States)

    MacKay, P; Pasek, M; Magazin, M; Kovacic, R T; Allet, B; Stahl, S; Gilbert, W; Schaller, H; Bruce, S A; Murray, K

    1981-01-01

    Several plasmids have been constructed which direct the synthesis of hepatitis B virus surface antigens in Escherichia coli either as the native polypeptide or fused to other plasmid encoded polypeptides. When injected into rabbits, extracts from bacteria carrying some of these plasmids induced the synthesis of antibodies to the antigens even though the extracts did not give satisfactory positive results in radioimmunoassay for them. Either the NH2-terminal segment or the COOH-terminal segment of the surface antigens alone was sufficient to elicit the immune response, but antibodies against the two segments showed different specificities. The results emphasize the value of an in vivo assay for the presence of antigens in crude cell extracts and illustrate the feasibility of this type of screening with laboratory animals. PMID:6170067

  16. [Development of an antigen 'sandwich' enzyme immunoassay for the detection of antibodies against HIV-2 by using a biotinylated synthetic peptide of gp36 protein].

    Science.gov (United States)

    Delahanty-Fernández, Aurora; Bequer-Ariza, Dunia Clara; Hernández-Marín, Milenen; Zulueta-Rodríguez, Orlando; Pozo-Peña, Lilliam; Hernández-Spengler, Idialis; Ramos-Martínez, Grisell; Valdespino-Díaz, Marcos Antonio; Ventura-Paz, Julio

    2015-01-01

    Among the several existing methods for the detection of antibodies to HIV, the 'sandwich' ELISA is currently the most used. This study aims to assess a biotinylated monomeric synthetic peptide of the glycoprotein trans-membrane gp36 from HIV-2, in a sandwich assay, for the detection of antibodies against this HIV-2 protein. To perform the assay, plates coated with recombinant protein gp36 at 0.5μg/mL and synthetic peptide gp36(5) at 1μg/mL were used. The concentration of the biotinylated synthetic peptide (gp36(5)-B) used was 0.1μg/mL prepared with a Tris-BSA-NaCl buffer solution and the Streptavidin- Alkaline Phosphatase conjugate diluted 1:30000 prepared with a PBS-Sucrose-BSA solution. Positive serum samples to antibodies against HIV-1 and HIV-2 viruses (88 and 34, respectively) were tested, with 483 negative samples from blood donors and 96 serum samples to assess the analytical specificity. All the samples were tested using the UMELISA HIV 1+2 RECOMBINANT assay, and all positives were confirmed using a DAHIV-BLOT assay. Thirty four samples with antibodies against HIV-2 were assessed as positive for both coating variants. The highest specificity was obtained with the variant using the synthetic peptide gp36(5) in its coating. The antigen 'sandwich' assay developed by using gp36(5)-B enables the detection of antibodies against gp36 protein of HIV-2. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  17. Viral antigen production in cell cultures on microcarriers Bovine parainfluenza 3 virus and MDBK cells.

    Science.gov (United States)

    Conceição, M M; Tonso, A; Freitas, C B; Pereira, C A

    2007-11-07

    Viral antigens can be obtained from infected mammalian cells cultivated on microcarriers. We have worked out parameters for the production of bovine parainfluenza 3 (PI-3) virus by Mandin-Darby Bovine Kidney (MDBK) cells cultivated on Cytodex 1 microcarriers (MCs) in spinners flasks and bioreactor using fetal bovine serum (FBS) supplemented Eagle minimal essential medium (Eagle-MEM). Medium renewal during the cell culture was shown to be crucial for optimal MCs loading (>90% MCs with confluent cell monolayers) and cell growth (2.5 x 10(6)cells/mL and a micro(x) (h(-1)) 0.05). Since cell cultures performed with lower amount of MCs (1g/L), showed good performances in terms of cell loading, we designed batch experiments with a lower concentration of MCs in view of optimizing the cell growth and virus production. Studies of cell growth with lower concentrations of MCs (0.85 g/L) showed that an increase in the initial cell seeding (from 7 to 40 cells/MC) led to a different kinetic of initial cell growth but to comparable final cell concentrations ((8-10)x10(5)cells/mL at 120 h) and cell loading (210-270 cells/MC). Upon infection with PI-3 virus, cultures showed a decrease in cell growth and MC loading directly related to the multiplicity of infection (moi) used for virus infection. Infected cultures showed also a higher consumption of glucose and production of lactate. The PI-3 virus and PI-3 antigen production among the cultures was not significantly different and attained values ranging from, respectively, 7-9 log(10) TCID(50)/mL and 1.5-2.2 OD. The kinetics of PI-3 virus production showed a sharp increase during the first 24h and those of PI-3 antigen increased after 24h. The differential kinetics of PI-3 virus and PI-3 antigen can be explained by the virus sensitivity to temperature. In view of establishing a protocol of virus production and based on the previous experiments, MDBK cell cultures performed under medium perfusion in a bioreactor of 1.2L were infected

  18. Multiple transmissions of a stable human leucocyte antigen-B27 cytotoxic T-cell-escape strain of HIV-1 in The Netherlands.

    Science.gov (United States)

    Cornelissen, Marion; Hoogland, Frederik M; Back, Nicole K T; Jurriaans, Suzanne; Zorgdrager, Fokla; Bakker, Margreet; Brinkman, Kees; Prins, Maria; van der Kuyl, Antoinette C

    2009-07-31

    The evolution of HIV-1 is largely shaped by the cytotoxic T-cell (CTL) response of the host as encoded by the human leucocyte antigen (HLA) genes. Certain HLA-B alleles can delay disease progression, but it is uncertain whether this protection will sustain or whether the virus is in the process of adaptation. In The Netherlands, HLA-B27 is moderately prevalent (approximately 8-16% of HLA-B alleles). If adaptation to HLA-B alleles is in progress, virus strains carrying escape mutations to HLA-B27 should appear in the epidemic by now. A subtype B HIV-1 strain carrying a HLA-B27 CTL-escape mutation in the main Gag-p24 KK10 epitope, R264G, together with a compensatory mutation outside this epitope, E260D, was detected in four patients from Amsterdam, The Netherlands, by sequence analysis of the gag gene. The patients were a drug user and three men who have sex with men, and were infected with HIV-1 between 2002 and 2008. Characterization and evolutionary analysis of the HIV-1 CTL-escape strain was done by sequence analysis of serial blood plasma samples. The mutations involved were stable during follow-up and after transmission, also in two individuals lacking HLA-B27. The finding that a stable HLA-B27 CTL-escape strain is circulating in The Netherlands has important implications for the understanding of virus-host interactions and vaccine design alike. Vaccines targeted at inducing a CTL response might easily be circumvented by the virus. Also, patients carrying protective HLA alleles might not be protected anymore from disease progression in the future.

  19. ANTIGENIC AND GENETIC CHARACTERIZATION OF INFLUENZA B VIRUSES IN 2012 FROM SLUMS, DHAKA, BANGLADESH.

    Science.gov (United States)

    Islam, Mohammad Ariful; Sultana, Nazneen; Ahmed, Firoz; Rahman, M Majibur; Rahman, Sabita Rezwana

    2015-07-01

    Nasal and throat swab samples were collected from 400 subjects with influenza-like illness during June to September, 2012 from two heavily crowded slums, Rayerbazar and Hazaribagh, situated southeast of Dhaka, Bangladesh. Forty-one samples were positive for influenza B virus using quantitative RT-PCR, but no influenza A virus was detected. Antigenic characterization revealed that the influenza B viruses were of Yamagata and Victoria lineages, which was confirmed from genetic analysis of hemagglutinin (HA) and neuraminidase (NA) genes. Co-circulation of influenza B viruses of both Yamagata and Victoria lineages in the slums of Dhaka indicates that introduction of a tetravalent vaccine formulation that includes both of these influenza B virus lineages would be more effective in this population.

  20. Hepatitis B virus and HIV co-infection among pregnant women in Rwanda.

    Science.gov (United States)

    Mutagoma, Mwumvaneza; Balisanga, Helene; Malamba, Samuel S; Sebuhoro, Dieudonné; Remera, Eric; Riedel, David J; Kanters, Steve; Nsanzimana, Sabin

    2017-09-11

    Hepatitis B virus (HBV) affects people worldwide but the local burden especially in pregnant women and their new born babies is unknown. In Rwanda HIV-infected individuals who are also infected with HBV are supposed to be initiated on ART immediately. HBV is easily transmitted from mother to child during delivery. We sought to estimate the prevalence of chronic HBV infection among pregnant women attending ante-natal clinic (ANC) in Rwanda and to determine factors associated with HBV and HIV co-infection. This study used a cross-sectional survey, targeting pregnant women in sentinel sites. Pregnant women were tested for hepatitis B surface antigen (HBsAg) and HIV infection. A series of tests were done to ensure high sensitivity. Multivariable logistic regression was used to identify independent predictors of HBV-HIV co-infection among those collected during ANC sentinel surveillance, these included: age, marital status, education level, occupation, residence, pregnancy and syphilis infection. The prevalence of HBsAg among 13,121 pregnant women was 3.7% (95% CI: 3.4-4.0%) and was similar among different socio-demographic characteristics that were assessed. The proportion of HIV-infection among HBsAg-positive pregnant women was 4.1% [95% CI: 2.5-6.3%]. The prevalence of HBV-HIV co-infection was higher among women aged 15-24 years compared to those women aged 25-49 years [aOR = 6.9 (95% CI: 1.8-27.0)]. Women residing in urban areas seemed having HBV-HIV co-infection compared with women residing in rural areas [aOR = 4.3 (95% CI: 1.2-16.4)]. Women with more than two pregnancies were potentially having the co-infection compared to those with two or less (aOR = 6.9 (95% CI: 1.7-27.8). Women with RPR-positive test were seemed associated with HBV-HIV co-infection (aOR = 24.9 (95% CI: 5.0-122.9). Chronic HBV infection is a public health problem among pregnant women in Rwanda. Understanding that HBV-HIV co-infection may be more prominent in younger women from urban

  1. Antibody to histo-blood group A antigen neutralizes HIV produced by lymphocytes from blood group A donors but not from blood group B or O donors

    DEFF Research Database (Denmark)

    Arendrup, M; Hansen, J E; Clausen, H

    1991-01-01

    Three virus isolates HTLV-IIIB/lyA, HTLV-IIIB/lyB and HTLV-IIIB/lyO, obtained by passaging and propagating the HTLV-IIIB/H9 isolate in three separate cultures of mixed peripheral blood mononuclear cells (PBMC) from donors of blood type A, B or O, respectively, were tested for susceptibility...... not inhibit the HTLV-IIIB/lyB or the HTLV-IIIB/lyO isolate. Specificity of the MAb-mediated inhibition was shown using A-antigen (tetrasaccharide). Thus, HIV infection of PBMC from donors with blood type A appears to induce expression of host-cell-encoded carbohydrate blood group A epitope on HIV which can...

  2. The influence of human leukocyte antigen class I alleles and their population frequencies on human immunodeficiency virus type 1 control among African Americans.

    Science.gov (United States)

    Lazaryan, Aleksandr; Song, Wei; Lobashevsky, Elena; Tang, Jianming; Shrestha, Sadeep; Zhang, Kui; McNicholl, Janet M; Gardner, Lytt I; Wilson, Craig M; Klein, Robert S; Rompalo, Anne; Mayer, Kenneth; Sobel, Jack; Kaslow, Richard A

    2011-04-01

    Populations of African ancestry continue to account for a disproportionate burden of the human immunodeficiency virus type 1 (HIV-1) epidemic in the United States. We investigated the effects of human leukocyte antigen (HLA) class I markers in association with virologic and immunologic control of HIV-1 infection among 338 HIV-1 subtype B-infected African Americans in 2 cohorts: Reaching for Excellence in Adolescent Care and Health (REACH) and HIV Epidemiology Research Study (HERS). One-year treatment-free interval measurements of HIV-1 RNA viral loads and CD4(+) T cells were examined both separately and combined to represent 3 categories of HIV-1 disease control (76 controllers, 169 intermediates, and 93 noncontrollers). Certain previously or newly implicated HLA class I alleles (A*32, A*36, A*74, B*14, B*1510, B*3501, B*45, B*53, B*57, Cw*04, Cw*08, Cw*12, and Cw*18) were associated with 1 or more of the endpoints in univariate analyses. After multivariable adjustments for other genetic and nongenetic risk factors of HIV-1 progression, the subset of alleles more strongly or consistently associated with HIV-1 disease control included A*32, A*74, B*14, B*45, B*53, B*57, and Cw*08. Carriage of infrequent HLA-B but not HLA-A alleles was associated with more favorable disease outcomes. Certain HLA class I associations with control of HIV-1 infection cross the boundaries of race and viral subtype, whereas others appear confined within one or the other of those boundaries. Copyright © 2011 American Society for Histocompatibility and Immunogenetics. All rights reserved.

  3. ViroSpot microneutralization assay for antigenic characterization of human influenza viruses.

    Science.gov (United States)

    van Baalen, Carel A; Jeeninga, Rienk E; Penders, Germaine H W M; van Gent, Brenda; van Beek, Ruud; Koopmans, Marion P G; Rimmelzwaan, Guus F

    2017-01-03

    The hemagglutination inhibition (HI) assay has been used for the antigenic characterization of influenza viruses for decades. However, the majority of recent seasonal influenza A viruses of the H3N2 subtype has lost the capacity to agglutinate erythrocytes of various species. The hemagglutination (HA) activity of other A(H3N2) strains is generally sensitive to the action of the neuraminidase inhibitor oseltamivir, which indicates that the neuraminidase and not the hemagglutinin is responsible for the HA activity. These findings complicate the antigenic characterization and selection of A(H3N2) vaccine strains, calling for alternative antigenic characterization assays. Here we describe the development and use of the ViroSpot microneutralization (MN) assay as a reliable and robust alternative for the HI assay. Serum neutralization of influenza A(H3N2) reference virus strains and epidemic isolates was determined by automated readout of immunostained cell monolayers, in a format designed to minimize the influence of infectious virus doses on serum neutralization titers. Neutralization of infection was largely independent from rates of viral replication and cell-to-cell transmission, facilitating the comparison of different virus isolates. Other advantages of the ViroSpot MN assay include its relative insensitivity to variation in test dose of infectious virus, automated capture and analyses of residual infection patterns, and compatibility with standardized large scale analyses. Using this assay, a number of epidemic influenza A(H3N2) strains that failed to agglutinate erythrocytes, were readily characterized antigenically. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Intestinal Damage and Inflammatory Biomarkers in Human Immunodeficiency Virus (HIV)-Exposed and HIV-Infected Zimbabwean Infants.

    Science.gov (United States)

    Prendergast, Andrew J; Chasekwa, Bernard; Rukobo, Sandra; Govha, Margaret; Mutasa, Kuda; Ntozini, Robert; Humphrey, Jean H

    2017-09-15

    Disease progression is rapid in human immunodeficiency virus (HIV)-infected infants. Whether intestinal damage and inflammation underlie mortality is unknown. We measured plasma intestinal fatty acid binding protein (I-FABP), soluble CD14 (sCD14), interleukin 6 (IL-6), and C-reactive protein (CRP) at 6 weeks and 6 months of age in 272 HIV-infected infants who either died (cases) or survived (controls), and in 194 HIV-exposed uninfected (HEU) and 197 HIV-unexposed infants. We estimated multivariable odds ratios for mortality and postnatal HIV transmission for each biomarker using logistic regression. At 6 weeks, HIV-infected infants had higher sCD14 and IL-6 but lower I-FABP than HIV-exposed and HIV-unexposed infants (P HIV-exposed than HIV-unexposed infants (P = .02). At 6 months, HIV-infected infants had highest sCD14, IL-6, and CRP concentrations (P HIV-exposed vs HIV-unexposed infants (P = .04). No biomarker was associated with mortality in HIV-infected infants, or with odds of breast-milk HIV transmission in HIV-exposed infants. HIV-infected infants have elevated inflammatory markers by 6 weeks of age, which increase over time. In contrast to adults and older children, inflammatory biomarkers were not associated with mortality. HEU infants have higher inflammation than HIV-unexposed infants until at least 6 months, which may contribute to poor health outcomes.

  5. Dermatophytosis And Human Immunodeficiency Virus(HIV Infection

    Directory of Open Access Journals (Sweden)

    Sentamilselvi G

    1998-01-01

    Full Text Available The incidence of Human Immunodeficiency Virus (HIV antibody through Enzyme Linked Immunosorbant Assay (ELISA technique was observed to be 2.5% among the 200 patients with dermatophytosis. The incidence was less (1% in those with chronic disease compared to those with nonchronic disease (4%. The positivity seemed to be more in females screened. The clinical presentation of dermatophytosis in HIV positive patients was similar to that screen in general population. Trichophyton rubrum was the commonest isolate. Unusual widespread lesions and atypical lesions of nails like proximal subungual white onychomycosis were not encountered in the present series.

  6. The oral microbiome in human immunodeficiency virus (HIV)-positive individuals

    National Research Council Canada - National Science Library

    Kistler, James O; Arirachakaran, Pratanporn; Poovorawan, Yong; Dahlén, Gunnar; Wade, William G

    2015-01-01

    Human immunodeficiency virus (HIV) infection is associated with a range of oral conditions, and increased numbers of disease-associated microbial species have previously been found in HIV-positive subjects...

  7. Role of metalloproteases in vaccinia virus epitope processing for transporter associated with antigen processing (TAP)-independent human leukocyte antigen (HLA)-B7 class I antigen presentation.

    Science.gov (United States)

    Lorente, Elena; García, Ruth; Mir, Carmen; Barriga, Alejandro; Lemonnier, François A; Ramos, Manuel; López, Daniel

    2012-03-23

    The transporter associated with antigen processing (TAP) translocates the viral proteolytic peptides generated by the proteasome and other proteases in the cytosol to the endoplasmic reticulum lumen. There, they complex with nascent human leukocyte antigen (HLA) class I molecules, which are subsequently recognized by the CD8(+) lymphocyte cellular response. However, individuals with nonfunctional TAP complexes or tumor or infected cells with blocked TAP molecules are able to present HLA class I ligands generated by TAP-independent processing pathways. Herein, using a TAP-independent polyclonal vaccinia virus-polyspecific CD8(+) T cell line, two conserved vaccinia-derived TAP-independent HLA-B*0702 epitopes were identified. The presentation of these epitopes in normal cells occurs via complex antigen-processing pathways involving the proteasome and/or different subsets of metalloproteinases (amino-, carboxy-, and endoproteases), which were blocked in infected cells with specific chemical inhibitors. These data support the hypothesis that the abundant cellular proteolytic systems contribute to the supply of peptides recognized by the antiviral cellular immune response, thereby facilitating immunosurveillance. These data may explain why TAP-deficient individuals live normal life spans without any increased susceptibility to viral infections.

  8. Seroprevalence of Epstein-Barr virus among HIV positive patients moreover and its association with CD4 positive lymphocyte count.

    Directory of Open Access Journals (Sweden)

    Alireza Abdollahi

    2014-12-01

    Full Text Available Opportunistic infections are the leading cause of hospitalization and morbidity in human immunodeficiency virus (HIV positive patients and are the most common cause of death between them. We aimed to measure IgG antibody against EBV viral capsid antigen (EBV-VCA IgG to determine the seroprevalence of this infection in HIV-positive population. A case-control study between September 2011 and October 2012 was conducted in a teaching hospital enrolling 114 HIV-positive patients as case group and 114 healthy individuals as control with similar age and sex. Enzyme-linked immunosurbant assay (ELISA technique was used for determination of EBV-VAC IgG in obtained samples. Of 114 serum samples obtained from HIV-positive patients, 103 (90.4% samples were found positive for EBV-VCA IgG antibody. There was no significant difference in seroprevalence of EBV VCA IgG antibody between patients received antiretroviral therapy and naive patients (91.5% vs. 87.5%, P>0.05. There was no statistically significant difference in EBV-VCA IgG seroprevalence between three groups of CD4+ in HIV positive group. In conclusion current study showed that seroprevalence of EBV in HIV-positive patients is higher than HIV-negative healthy participants; however, administration of HAART and CD4+ lymphocyte count did not reveal a significant effect in seroprevalence of EBV. Due to the significance of this virus in mortality and morbidity and causing certain malignancies in patients with AIDS, these patients are strongly recommended to be tested for this virus.

  9. Mannosylation of virus-like particles enhances internalization by antigen presenting cells.

    Directory of Open Access Journals (Sweden)

    Farah Al-Barwani

    Full Text Available Internalization of peptides by antigen presenting cells is crucial for the initiation of the adaptive immune response. Mannosylation has been demonstrated to enhance antigen uptake through mannose receptors, leading to improved immune responses. In this study we test the effect of surface mannosylation of protein-based virus-like particles (VLP derived from Rabbit hemorrhagic disease virus (RHDV on uptake by murine and human antigen presenting cells. A monomannoside and a novel dimannoside were synthesized and successfully conjugated to RHDV VLP capsid protein, providing approximately 270 mannose groups on the surface of each virus particle. VLP conjugated to the mannoside or dimannoside exhibited significantly enhanced binding and internalization by murine dendritic cells, macrophages and B cells as well as human dendritic cells and macrophages. This uptake was inhibited by the inclusion of mannan as a specific inhibitor of mannose specific uptake, demonstrating that mannosylation of VLP targets mannose receptor-based uptake. Consistent with mannose receptor-based uptake, partial retargeting of the intracellular processing of RHDV VLP was observed, confirming that mannosylation of VLP provides both enhanced uptake and modified processing of associated antigens.

  10. Recovery of West Nile Virus Envelope Protein Domain III Chimeras with Altered Antigenicity and Mouse Virulence.

    Science.gov (United States)

    McAuley, Alexander J; Torres, Maricela; Plante, Jessica A; Huang, Claire Y-H; Bente, Dennis A; Beasley, David W C

    2016-05-01

    Flaviviruses are positive-sense, single-stranded RNA viruses responsible for millions of human infections annually. The envelope (E) protein of flaviviruses comprises three structural domains, of which domain III (EIII) represents a discrete subunit. The EIII gene sequence typically encodes epitopes recognized by virus-specific, potently neutralizing antibodies, and EIII is believed to play a major role in receptor binding. In order to assess potential interactions between EIII and the remainder of the E protein and to assess the effects of EIII sequence substitutions on the antigenicity, growth, and virulence of a representative flavivirus, chimeric viruses were generated using the West Nile virus (WNV) infectious clone, into which EIIIs from nine flaviviruses with various levels of genetic diversity from WNV were substituted. Of the constructs tested, chimeras containing EIIIs from Koutango virus (KOUV), Japanese encephalitis virus (JEV), St. Louis encephalitis virus (SLEV), and Bagaza virus (BAGV) were successfully recovered. Characterization of the chimeras in vitro and in vivo revealed differences in growth and virulence between the viruses, within vivo pathogenesis often not being correlated within vitro growth. Taken together, the data demonstrate that substitutions of EIII can allow the generation of viable chimeric viruses with significantly altered antigenicity and virulence. The envelope (E) glycoprotein is the major protein present on the surface of flavivirus virions and is responsible for mediating virus binding and entry into target cells. Several viable West Nile virus (WNV) variants with chimeric E proteins in which the putative receptor-binding domain (EIII) sequences of other mosquito-borne flaviviruses were substituted in place of the WNV EIII were recovered, although the substitution of several more divergent EIII sequences was not tolerated. The differences in virulence and tissue tropism observed with the chimeric viruses indicate a

  11. Epstein Barr virus-encoded EBNA1 interference with MHC class I antigen presentation reveals a close correlation between mRNA translation initiation and antigen presentation.

    Science.gov (United States)

    Apcher, Sebastien; Daskalogianni, Chrysoula; Manoury, Benedicte; Fåhraeus, Robin

    2010-10-14

    Viruses are known to employ different strategies to manipulate the major histocompatibility (MHC) class I antigen presentation pathway to avoid recognition of the infected host cell by the immune system. However, viral control of antigen presentation via the processes that supply and select antigenic peptide precursors is yet relatively unknown. The Epstein-Barr virus (EBV)-encoded EBNA1 is expressed in all EBV-infected cells, but the immune system fails to detect and destroy EBV-carrying host cells. This immune evasion has been attributed to the capacity of a Gly-Ala repeat (GAr) within EBNA1 to inhibit MHC class I restricted antigen presentation. Here we demonstrate that suppression of mRNA translation initiation by the GAr in cis is sufficient and necessary to prevent presentation of antigenic peptides from mRNAs to which it is fused. Furthermore, we demonstrate a direct correlation between the rate of translation initiation and MHC class I antigen presentation from a certain mRNA. These results support the idea that mRNAs, and not the encoded full length proteins, are used for MHC class I restricted immune surveillance. This offers an additional view on the role of virus-mediated control of mRNA translation initiation and of the mechanisms that control MHC class I restricted antigen presentation in general.

  12. Human Immunodeficiency Virus (HIV) Research (AIDS)

    Science.gov (United States)

    1991-02-28

    pathophysiology measured during follow-up. I. Compare neuropsychiatric and psychosocial findings in HIV-infected military personnel with non-infected military...venipuncture, and possible rare side effects of PTU therapy - hypothyroidism , skin rash, myalgias, arthralgias, hepatitis, edema. *23 RV47 A Randomized

  13. Hepatitis C Virus Core Antigen Test in Monitoring of Dialysis Patients

    Directory of Open Access Journals (Sweden)

    Gioacchino Li Cavoli

    2012-01-01

    Full Text Available Hepatitis C virus infection is a persistent worldwide public health concern. The prevalence of HCV infection is much higher in patients on chronic haemodialysis (HD than in the general population. HCV infection can detrimentally affect patients throughout the spectrum of chronic kidney disease. Despite the control of blood products, hepatitis C virus transmission is still being observed among patients undergoing dialysis. Detection systems for serum HCV antibodies are insensitive in the acute phase because of the long serological window. Direct detection of HCV depends on PCR test but this test is not suitable for routine screening. Recent studies have highlighted the importance of HCV core antigen detection as an alternative to PCR. Few studies exist about the efficacy of HCV core antigen test in dialysis population. We studied the utility of HCV core antigen test in routine monitoring of virological status of dialysis patients. We screened 92 patients on long-term dialysis both by PCR HCV-RNA and HCV core antigen test. The sensitivity of HCVcAg test was 90%, the specificity 100%, the positive predictive power 100%, the negative predictive power 97%, and the accuracy 97%. We think serological detection of HCV core antigen may be an alternative to NAT techniques for routine monitoring of patients on chronic dialysis.

  14. Virus-Specific Deoxyribonucleic Acid in Simian Virus 40-Exposed Hamster Cells: Correlation with S and T Antigens 1

    Science.gov (United States)

    Levine, Arthur S.; Oxman, Michael N.; Henry, Patrick H.; Levin, Myron J.; Diamandopoulos, George T.; Enders, John F.

    1970-01-01

    Several homologous hamster embryonic cell lines, transformed in association with simian virus (SV) 40 infection, were examined for the presence of deoxyribonucleic acid (DNA) complementary to SV40 ribonucleic acid (RNA) made in vitro. The methods employed permitted the detection of 10−5 μg of viral DNA in 100 μg of cellular DNA, corresponding to one-fifth of an SV40 DNA molecule per cell. Those lines which contained both the SV40 surface (S) and tumor (T) antigens also contained DNA complementary to SV40 RNA synthesized in vitro. In contrast, neither of two lines which contained S, but not T, antigen contained detectable DNA complementary to SV40 RNA. These findings suggest that the production of S antigen does not depend upon the persistence of SV40 DNA in transformed cells. PMID:4322872

  15. Virus-specific deoxyribonucleic acid in simian virus 40-exposed hamster cells: correlation with S and T antigens.

    Science.gov (United States)

    Levine, A S; Oxman, M N; Henry, P H; Levin, M J; Diamandopoulos, G T; Enders, J F

    1970-08-01

    Several homologous hamster embryonic cell lines, transformed in association with simian virus (SV) 40 infection, were examined for the presence of deoxyribonucleic acid (DNA) complementary to SV40 ribonucleic acid (RNA) made in vitro. The methods employed permitted the detection of 10(-5) mug of viral DNA in 100 mug of cellular DNA, corresponding to one-fifth of an SV40 DNA molecule per cell. Those lines which contained both the SV40 surface (S) and tumor (T) antigens also contained DNA complementary to SV40 RNA synthesized in vitro. In contrast, neither of two lines which contained S, but not T, antigen contained detectable DNA complementary to SV40 RNA. These findings suggest that the production of S antigen does not depend upon the persistence of SV40 DNA in transformed cells.

  16. Serological response to Epstein-Barr virus early antigen is associated with gastric cancer and human immunodeficiency virus infection in Zambian adults: a case-control study.

    Science.gov (United States)

    Kayamba, Violet; Monze, Mwaka; Asombang, Akwi Wasi; Zyambo, Kanekwa; Kelly, Paul

    2016-01-01

    Gastric cancer is one of the major causes of cancer related deaths, but data from sub-Saharan Africa are very scanty. The cancer genome atlas (TCGA) initiative confirmed Epstein-Barr virus (EBV) related cancer as a distinct subtype, and we set out to look for serological evidence of its role in a sub-Saharan African patient group. We used stored serum samples obtained from a gastric cancer case-control study conducted between 2010 and 2012 in Lusaka, Zambia. A total of 147 patients were included with 51 gastric adenocarcinoma cases and 96 age and sex matched controls. The presence of antibodies to EBV nuclear antigen-1 (EBNA-1) and early antigen (EA) was determined using commercially available ELISA kits. Data were analysed in STATA Stata Corp, College Station TX. Over 90% of all the samples analysed were positive for antibodies to EBNA-1. The presence of antibodies to EBV EA was significantly higher in gastric cancer cases than in controls, (OR 4.38; 95% CI 1.53-13.06, P = 0.0027), with an attributable risk of 23%. HIV infection was also associated with EBV EA seroprevalence (OR 10.97; 95% CI 2.26 -13.06, P = 0.001) but not EBNA-1 (OR 0.81; 95% CI 0.10 -38.75, P = 0.596). There was no association of EBV infection with age below 45 years, Helicobacter pylori infection, intestinal metaplasia, gastric atrophy or inflammation. We therefore conclude that EBV exposure is common among Zambian adults and that EBV EA seropositivity is associated with gastric cancer and HIV infection, but not premalignant lesions.

  17. Transgenic lettuce seedlings carrying hepatitis B virus antigen HBsAg

    Directory of Open Access Journals (Sweden)

    Jackson Marcondes

    Full Text Available The obtainment of transgenic edible plants carrying recombinant antigens is a desired issue in search for economic alternatives viewing vaccine production. Here we report a strategy for genetic transformation of lettuce plants (Lactuca sativa L. using the surface antigen HBsAg of hepatitis B virus. Transgenic lettuce seedlings were obtained through the application of a regulated balance of plant growth regulators. Genetic transformation process was acquired by cocultivation of cotyledons with Agrobacterium tumefaciens harboring the recombinant plasmid. It is the first description of a lettuce Brazilian variety "Vitória de Verão" genetically modified.

  18. Evolving T-cell vaccine strategies for HIV, the virus with a thousand faces

    Energy Technology Data Exchange (ETDEWEB)

    Korber, Bette [Los Alamos National Laboratory

    2009-01-01

    HIV's rapid global spread and the human suffering it has left in its wake have made AIDS a global heath priority for the 25 years since its discovery. Yet its capacity to rapidly evolve has made combating this virus a tremendous challenge. The obstacles to creating an effective HIV vaccine are formidable, but there are advances in the field on many fronts, in terms of novel vectors, adjuvants, and antigen design strategies. SIV live attenuated vaccine models are able to confer protection against heterologous challenge, and this continues to provide opportunities to explore the biological underpinnings of a protective effect (9). More indirect, but equally important, is new understanding regarding the biology of acute infection (43), the role of immune response in long-term non-progression (6,62, 81), and defining characteristics of broadly neutralizing antibodies (4). In this review we will focus on summarizing strategies directed towards a single issue, that of contending with HIV variation in terms of designing aT-cell vaccine. The strategies that prove most effective in this area can ultimately be combined with the best strategies under development in other areas, with the hope of ultimately converging on a viable vaccine candidate. Only two large HIV vaccine efficacy trials have been completed and both have failed to prevent infection or confer a benefit to infected individual (23,34), but there is ample reason to continue our efforts. A historic breakthrough came in 1996, when it was realized that although the virus could escape from a single antiretroviral (ARV) therapy, it could be thwarted by a combination of medications that simultaneously targeted different parts of the virus (HAART) (38). This revelation came after 15 years of research, thought, and clinical testing; to enable that vital progress the research and clinical communities had to first define and understand, then develop a strategy to counter, the remarkable evolutionary potential of the

  19. Human immunodeficiency virus type-1 (HIV-1) genetic diversity and ...

    African Journals Online (AJOL)

    PROGMANAGER

    2013-04-24

    Apr 24, 2013 ... Human immunodeficiency virus type-1 (HIV-1) genetic diversity and prevalence of antiretroviral drug resistance mutations in treatment-naïve adults in Jos,. North Central Nigeria. Anejo-Okopi J. A.1*, Agbaji O. O.1,2, Agaba P. A.1,3, Ugoagwu P. O.1, Were K.4, Onywera H.4,. Owiti P.4, Isa S. E1,2, Otecko N.4 ...

  20. Human immunodeficiency virus (HIV) and infertility treatment: a committee opinion.

    Science.gov (United States)

    2015-07-01

    Human immunodeficiency virus (HIV) is a serious but manageable chronic disease that affects persons of reproductive age, many of whom express a desire for biologic parenthood. This document is a revision of the original document of the same name, last published in 2010 (Fertil Steril 2010;94:11-5). Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  1. Enhanced Sensitivity for Detection of HIV-1 p24 Antigen by a Novel Nuclease-Linked Fluorescence Oligonucleotide Assay.

    Directory of Open Access Journals (Sweden)

    Peihu Fan

    Full Text Available The relatively high detection limit of the Enzyme-linked immunosorbent assay (ELISA prevents its application for detection of low concentrations of antigens. To increase the sensitivity for detection of HIV-1 p24 antigen, we developed a highly sensitive nuclease-linked fluorescence oligonucleotide assay (NLFOA. Two major improvements were incorporated in NLFOA to amplify antibody-antigen interaction signals and reduce the signal/noise ratio; a large number of nuclease molecules coupled to the gold nanoparticle/streptavidin complex and fluorescent signals generated from fluorescent-labeled oligonucleotides by the nuclease. The detection limit of p24 by NLFOA was 1 pg/mL, which was 10-fold more sensitive than the conventional ELISA (10 pg/mL. The specificity was 100% and the coefficient of variation (CV was 7.8% at low p24 concentration (1.5 pg/mL with various concentrations of spiked p24 in HIV-1 negative sera. Thus, NLFOA is highly sensitive, specific, reproducible and user-friendly. The more sensitive detection of low p24 concentrations in HIV-1-infected individuals by NLFOA could allow detection of HIV-1 infections that are missed by the conventional ELISA at the window period during acute infection to further reduce the risk for HIV-1 infection due to the undetected HIV-1 in the blood products. Moreover, NLFOA can be easily applied to more sensitive detection of other antigens.

  2. A candidate HIV/AIDS vaccine (MVA-B lacking vaccinia virus gene C6L enhances memory HIV-1-specific T-cell responses.

    Directory of Open Access Journals (Sweden)

    Juan García-Arriaza

    Full Text Available The vaccinia virus (VACV C6 protein has sequence similarities with the poxvirus family Pox_A46, involved in regulation of host immune responses, but its role is unknown. Here, we have characterized the C6 protein and its effects in virus replication, innate immune sensing and immunogenicity in vivo. C6 is a 18.2 kDa protein, which is expressed early during virus infection and localizes to the cytoplasm of infected cells. Deletion of the C6L gene from the poxvirus vector MVA-B expressing HIV-1 Env, Gag, Pol and Nef antigens from clade B (MVA-B ΔC6L had no effect on virus growth kinetics; therefore C6 protein is not essential for virus replication. The innate immune signals elicited by MVA-B ΔC6L in human macrophages and monocyte-derived dendritic cells (moDCs are characterized by the up-regulation of the expression of IFN-β and IFN-α/β-inducible genes. In a DNA prime/MVA boost immunization protocol in mice, flow cytometry analysis revealed that MVA-B ΔC6L enhanced the magnitude and polyfunctionality of the HIV-1-specific CD4+ and CD8+ T-cell memory immune responses, with most of the HIV-1 responses mediated by the CD8+ T-cell compartment with an effector phenotype. Significantly, while MVA-B induced preferentially Env- and Gag-specific CD8+ T-cell responses, MVA-B ΔC6L induced more Gag-Pol-Nef-specific CD8+ T-cell responses. Furthermore, MVA-B ΔC6L enhanced the levels of antibodies against Env in comparison with MVA-B. These findings revealed that C6 can be considered as an immunomodulator and that deleting C6L gene in MVA-B confers an immunological benefit by enhancing IFN-β-dependent responses and increasing the magnitude and quality of the T-cell memory immune responses to HIV-1 antigens. Our observations are relevant for the improvement of MVA vectors as HIV-1 vaccines.

  3. HUMAN-IMMUNODEFICIENCY-VIRUS (HIV) TYPE-1 INFECTION STATUS AND IN-VITRO SUSCEPTIBILITY TO HIV-INFECTION AMONG HIGH-RISK HIV-1 SERONEGATIVE HEMOPHILIACS

    NARCIS (Netherlands)

    LEDERMAN, MM; JACKSON, JB; KRONER, BL; WHITE, GC; EYSTER, ME; ALEDORT, LM; HILGARTNER, MW; KESSLER, CM; COHEN, AR; KIGER, KP; GOEDERT, JJ

    Blood samples were obtained from 16 hemophiliacs who had a 50%-94% defined risk of human immunodeficiency virus (HIV type 1 infection on the basis of treatment history and from 14 controls not at risk for HIV infection. HIV-1 was not detected in any of 12 patient samples by cocultivation nor in 14

  4. In vitro replication kinetics of human immunodeficiency virus type 1 (HIV-1) variants in relation to virus load in long-term survivors of HIV-1 infection

    NARCIS (Netherlands)

    Blaak, H.; Brouwer, M.; Ran, L. J.; de Wolf, F.; Schuitemaker, H.

    1998-01-01

    In 7 long-term survivors (LTS) and 8 progressors, all carrying solely non-syncytium-inducing variants, a possible correlation between in vitro virus replicative capacity, virus load, and clinical course of human immunodeficiency virus type 1 (HIV-1) infection was analyzed. Late in infection, 3 LTS

  5. Glutamic Acid Residues in HIV-1 p6 Regulate Virus Budding and Membrane Association of Gag.

    Science.gov (United States)

    Friedrich, Melanie; Setz, Christian; Hahn, Friedrich; Matthaei, Alina; Fraedrich, Kirsten; Rauch, Pia; Henklein, Petra; Traxdorf, Maximilian; Fossen, Torgils; Schubert, Ulrich

    2016-04-25

    The HIV-1 Gag p6 protein regulates the final abscission step of nascent virions from the cell membrane by the action of its two late (L-) domains, which recruit Tsg101 and ALIX, components of the ESCRT system. Even though p6 consists of only 52 amino acids, it is encoded by one of the most polymorphic regions of the HIV-1 gag gene and undergoes various posttranslational modifications including sumoylation, ubiquitination, and phosphorylation. In addition, it mediates the incorporation of the HIV-1 accessory protein Vpr into budding virions. Despite its small size, p6 exhibits an unusually high charge density. In this study, we show that mutation of the conserved glutamic acids within p6 increases the membrane association of Pr55 Gag followed by enhanced polyubiquitination and MHC-I antigen presentation of Gag-derived epitopes, possibly due to prolonged exposure to membrane bound E3 ligases. The replication capacity of the total glutamic acid mutant E0A was almost completely impaired, which was accompanied by defective virus release that could not be rescued by ALIX overexpression. Altogether, our data indicate that the glutamic acids within p6 contribute to the late steps of viral replication and may contribute to the interaction of Gag with the plasma membrane.

  6. Latency-Associated Nuclear Antigen Encoded by Kaposi's Sarcoma-Associated Herpesvirus Interacts with Tat and Activates the Long Terminal Repeat of Human Immunodeficiency Virus Type 1 in Human Cells

    OpenAIRE

    Hyun, Teresa S.; Subramanian, Chitra; Cotter, Murray A.; Robert A. Thomas; Robertson, Erle S.

    2001-01-01

    The latency-associated nuclear antigen (LANA) is constitutively expressed in cells infected with the Kaposi's sarcoma (KS) herpesvirus (KSHV), also referred to as human herpesvirus 8. KSHV is tightly associated with body cavity-based lymphomas (BCBLs) in immunocompromised patients infected with human immunodeficiency virus (HIV). LANA, encoded by open reading frame 73 of KSHV, is one of a small subset of proteins expressed during latent infection and was shown to be important in tethering the...

  7. Co-delivery of antigen and IL-12 by Venezuelan equine encephalitis virus replicon particles enhances antigen-specific immune responses and anti-tumor effects

    OpenAIRE

    Osada, Takuya; Berglund, Peter; Morse, Michael A.; Hubby, Bolyn; Lewis, Whitney; Niedzwiecki, Donna; Hobeika, Amy; Burnett, Bruce; Devi, Gayathri R.; Clay, Timothy M.; Smith, Jonathan; Lyerly, H. Kim

    2012-01-01

    We recently demonstrated that Venezuelan equine encephalitis (VEE) virus-based replicon particles (VRP) encoding tumor antigens could break tolerance in the immunomodulatory environment of advanced cancer. We hypothesized that local injection of VRP expressing Interleukin-12 (IL-12) at the site of injections of VRP-based cancer vaccines would enhance the tumor-antigen-specific T cell and antibody responses and anti-tumor efficacy. Mice were immunized with VRP encoding the human tumor-associat...

  8. Rotavirus antigen, cytokine, and neutralising antibody profiles in sera of children with and without HIV infection in Blantyre, Malawi.

    Science.gov (United States)

    Hull, Jennifer J; Cunliffe, Nigel; Jere, Khuzwayo C; Moon, Sung-Sil; Wang, Yuhuan; Parashar, Umesh; Jiang, Baoming

    2017-03-01

    Rotavirus and HIV infection are major causes of death among children in sub-Saharan Africa. A previous study reported no association between concomitant HIV infection and rotavirus disease severity among hospitalised children in Malawi. This study examined rotavirus antigenaemia and broader immune responses among HIV-infected and uninfected children. Stored (-80°C), paired sera from acute and convalescent phases of Malawian children less than 5 years old, hospitalised for acute gastroenteritis in the primary study, collected from July 1997 to June 1999, were utilised. Among children older than 15 months, HIV infection was defined as the presence of HIV antibody in the blood, when confirmed by at least 2 established methods. For those younger than 15 months, nested polymerase chain reaction (PCR) amplification of proviral DNA was used for verification. All were followed for up to 4 weeks after hospital discharge. Rotavirus antigen levels in sera were measured with Premier™ Rotaclone® rotavirus enzyme immunoassay (EIA) kit. Acute-phase sera were examined for 17 cytokines, using Luminex fluorescent bead human cytokine immunoassay kit. Rotavirus-specific IgA and neutralising activity were determined by EIA and microneutralisation (MN) assay, respectively. Human strains and bovine-human reassortants were propagated in MA104 cells with serum-free Iscove's Modified Dulbecco's Medium (IMDM). Differences in results, from specimens with and without HIV infection, were analysed for statistical significance using the chi-square test. We detected rotavirus antigen in 30% of the HIV-infected and 21% HIV-uninfected, in the acute-phase sera. HIV-infected children developed slightly prolonged rotavirus antigenaemia compared to HIV-uninfected children. Rotavirus-specific IgA seroconversion rates and neutralising titres were similar in HIV-infected and HIV-uninfected children, thus, HIV infection had no major effect on immune responses to rotavirus infection.

  9. Neutralizing monoclonal antibodies recognize antigenic variants among isolates of infectious hematopoietic necrosis virus

    Science.gov (United States)

    Winton, J.R.; Arakawa, C.N.; Lannan, C.N.; Fryer, J.L.

    1988-01-01

    eutralizing monoclonal antibodies were developed against strains of infectious hematopoietic necrosis virus (IHNV) from steelhead trout Salmo gairdneri in the Deschutes River of Oregon, chinook salmon Oncorhynchus tshawytscha in the Sacramento River of California, and rainbow trout Salmo gairdneri reared in the Hagerman Valley of Idaho, USA. These antibodies were tested for neutralization of 12 IHNV isolates obtained from salmonids in Japan, Alaska, Washington, Oregon, California, and Idaho. The antibodies recognized antigenic variants among the isolates and could be used to separate the viruses into 4 groups. The members of each group tended to be related by geographic area rather than by source host species, virulence, or date of isolation.

  10. Genetically modified anthrax lethal toxin safely delivers whole HIV protein antigens into the cytosol to induce T cell immunity

    Science.gov (United States)

    Lu, Yichen; Friedman, Rachel; Kushner, Nicholas; Doling, Amy; Thomas, Lawrence; Touzjian, Neal; Starnbach, Michael; Lieberman, Judy

    2000-07-01

    Bacillus anthrax lethal toxin can be engineered to deliver foreign proteins to the cytosol for antigen presentation to CD8 T cells. Vaccination with modified toxins carrying 8-9 amino acid peptide epitopes induces protective immunity in mice. To evaluate whether large protein antigens can be used with this system, recombinant constructs encoding several HIV antigens up to 500 amino acids were produced. These candidate HIV vaccines are safe in animals and induce CD8 T cells in mice. Constructs encoding gag p24 and nef stimulate gag-specific CD4 proliferation and a secondary cytotoxic T lymphocyte response in HIV-infected donor peripheral blood mononuclear cells in vitro. These results lay the foundation for future clinical vaccine studies.

  11. The Antigenic Structure of Zika Virus and Its Relation to Other Flaviviruses: Implications for Infection and Immunoprophylaxis

    Science.gov (United States)

    Stiasny, Karin

    2017-01-01

    SUMMARY Zika virus was discovered ∼70 years ago in Uganda and maintained a low profile as a human disease agent in Africa and Asia. Only recently has it caused explosive outbreaks in previously unaffected regions, first in Oceania and then in the Americas since 2015. Of special concern is the newly identified link between congenital malformations (especially microcephaly) and Zika virus infections during pregnancy. At present, it is unclear whether Zika virus changed its pathogenicity or whether the huge number of infections allowed the recognition of a previously cryptic pathogenic property. The purpose of this review is to discuss recent data on the molecular antigenic structure of Zika virus in the context of antibody-mediated neutralization and antibody-dependent enhancement (ADE) of infection, a phenomenon that has been implicated in the development of severe disease caused by the related dengue viruses. Emphasis is given to epitopes of antibodies that potently neutralize Zika virus and also to epitopes that provide antigenic links to other important human-pathogenic flaviviruses such as dengue, yellow fever, West Nile, Japanese encephalitis, and tick-borne encephalitis viruses. The antigenic cross talk between Zika and dengue viruses appears to be of special importance, since they cocirculate in many regions of endemicity and sequential infections are likely to occur frequently. New insights into the molecular antigenic structure of Zika virus and flaviviruses in general have provided the foundation for great progress made in developing Zika virus vaccines and antibodies for passive immunization. PMID:28179396

  12. The Antigenic Structure of Zika Virus and Its Relation to Other Flaviviruses: Implications for Infection and Immunoprophylaxis.

    Science.gov (United States)

    Heinz, Franz X; Stiasny, Karin

    2017-03-01

    Zika virus was discovered ∼70 years ago in Uganda and maintained a low profile as a human disease agent in Africa and Asia. Only recently has it caused explosive outbreaks in previously unaffected regions, first in Oceania and then in the Americas since 2015. Of special concern is the newly identified link between congenital malformations (especially microcephaly) and Zika virus infections during pregnancy. At present, it is unclear whether Zika virus changed its pathogenicity or whether the huge number of infections allowed the recognition of a previously cryptic pathogenic property. The purpose of this review is to discuss recent data on the molecular antigenic structure of Zika virus in the context of antibody-mediated neutralization and antibody-dependent enhancement (ADE) of infection, a phenomenon that has been implicated in the development of severe disease caused by the related dengue viruses. Emphasis is given to epitopes of antibodies that potently neutralize Zika virus and also to epitopes that provide antigenic links to other important human-pathogenic flaviviruses such as dengue, yellow fever, West Nile, Japanese encephalitis, and tick-borne encephalitis viruses. The antigenic cross talk between Zika and dengue viruses appears to be of special importance, since they cocirculate in many regions of endemicity and sequential infections are likely to occur frequently. New insights into the molecular antigenic structure of Zika virus and flaviviruses in general have provided the foundation for great progress made in developing Zika virus vaccines and antibodies for passive immunization. Copyright © 2017 American Society for Microbiology.

  13. Autologous HIV-1 neutralizing antibodies: emergence of neutralization-resistant escape virus and subsequent development of escape virus neutralizing antibodies

    DEFF Research Database (Denmark)

    Arendrup, M; Nielsen, C; Hansen, J E

    1992-01-01

    The capacity of consecutive human sera to neutralize sequentially obtained autologous virus isolates was studied. HIV-1 was isolated three times over a 48-164-week period from three individuals immediately after seroconversion and from two individuals in later stages of infection. Development...... escape virus may be part of the explanation of the apparent failure of the immune system to control HIV infection....... of neutralizing antibodies to the primary virus isolates was detected 13-45 weeks after seroconversion. Emergence of escape virus with reduced sensitivity to neutralization by autologous sera was demonstrated. The patients subsequently developed neutralizing antibodies against the escape virus but after a delay...

  14. Novel adenovirus encoded virus-like particles displaying the placental malaria associated VAR2CSA antigen

    DEFF Research Database (Denmark)

    Andersson, Anne-Marie C; dos Santos Marques Resende, Mafalda; Salanti, Ali

    2017-01-01

    and the CSA binding region of VAR2CSA has been identified as a promising vaccine target against placental malaria. Here we designed adenovirus encoded virus-like particles (VLP) by co-encoding Simian Immunodeficiency Virus (SIV) gag and VAR2CSA. The VAR2CSA antigen was fused to the transmembrane (TM......The malaria parasite Plasmodium falciparum presents antigens on the infected erythrocyte surface that bind human receptors expressed on the vascular endothelium. The VAR2CSA mediated binding to a distinct chondroitin sulphate A (CSA) is a crucial step in the pathophysiology of placental malaria......CSA fused to HA TM-CT was significantly superior in inducing ID1-ID2a specific antibodies after the first immunization. A sequential study was performed to include a comparison to the soluble VAR2CSA protein vaccine, which has entered a phase I clinical trial (NCT02647489). The results revealed...

  15. Antigenic determinants of influenza virus hemagglutinin. XI. Conformational changes detected by monoclonal antibodies.

    Science.gov (United States)

    Jackson, D C; Nestorowicz, A

    1985-08-01

    At pH 5 influenza virus hemagglutinin undergoes an irreversible conformational change (J.J. Skehel, P. M. Bayley, E. B. Brown, S. R. Martin, M. D. Waterfield, J. M. White, I. A. Wilson, and D. C. Wiley (1982). Proc. Natl. Acad. Sci. USA 79, 968-972) which parallels the appearance of fusion activity of this molecule. This paper describes experiments which explore the conformational change using a panel of monoclonal antibodies which define four of the major antigenic sites of this protein. The results indicate that three of the major antigenic sites of hemagglutinin undergo changes when exposed to acid pH. These changes have little effect on the binding avidity of influenza virus to glycophorin, the major receptor present on the red blood cell surface. These findings have been used to postulate a mechanism where the molecule flexes around a central region resulting in rearrangement in space of its component domains on exposure to low pH.

  16. Synthesis of bovine leukemia virus antigens in Escherichia coli.

    Science.gov (United States)

    Ulrich, R; Siakkou, H; Platzer, C; Bossmann, H; Möhring, R; Wiedmann, M; Bähring, S; Rosenthal, S

    1990-01-01

    Plasmids were constructed by the use of pEX vectors that encode and express different parts of the bovine leukemia virus (BLV): main core protein p24, nucleic acid-binding protein p12, transmembrane protein gp30, and different segments of envelope protein gp51. Expression of fusion proteins with molecular weights higher than 117 kD for all recombinant plasmids was shown in Coomassie-blue stained gels and by Western blot analysis with rabbit anti-BLV sera. Coupling of a gp51-encoding with a p24-encoding DNA fragment in pEX vectors led to synthesis of a fusion protein that was recognized by monoclonal antibodies directed against gp51 and p24 epitopes. Using another vector, a gp51-encoding DNA fragment of BLV was expressed as a fusion protein with 100 amino acids of the MS2 polymerase. The fusion protein was recognized by monoclonal antibodies directed against gp51.

  17. Production of vesicular stomatitis virus by antigen- or mitogen-stimulated lymphocytes and continuous lymphoblastoid lines

    Energy Technology Data Exchange (ETDEWEB)

    Nowakowski, M.; Feldman, J.D.; Kano, S.; Bloom, B.R.

    1973-04-01

    The purpose of this study is to explore at the ultrastructural level the nature of the cells engaged in the production of vesicular stomatitis virus (VSV) in different lymphoid cell populations, particularly after stimulation with several different agents. Specifically, we have examined (a) lymph node cells from guinea pigs with delayed hypersensitivity activated by specific antigen, (b) murine spleen cells activated by selective B cell and T cell mitogens, and (c) cells of human and murine continuous lymphoblastoid or lymphoma lines.

  18. Limited overlap between phylogenetic HIV and hepatitis C virus clusters illustrates the dynamic sexual network structure of Dutch HIV-infected MSM

    NARCIS (Netherlands)

    Vanhommerig, Joost W.; Bezemer, Daniela; Molenkamp, Richard; van Sighem, Ard I.; Smit, Colette; Arends, Joop E.; Lauw, Fanny N.; Brinkman, Kees; Rijnders, Bart J.; Newsum, Astrid M.; Bruisten, Sylvia M.; Prins, Maria; van der Meer, Jan T.; van de Laar, Thijs J.; Schinkel, Janke

    2017-01-01

    Objective: MSM are at increased risk for infection with HIV-1 and hepatitis C virus (HCV). Is HIV/HCV coinfection confined to specific HIV transmission networks? Design and methods: A HIV phylogenetic tree was constructed for 5038 HIV-1 subtype B polymerase (pol) sequences obtained from MSM in the

  19. Detection in human breast carcinomas of an antigen immunologically related to a group-specific antigen of mouse mammary tumor virus.

    Science.gov (United States)

    Mesa-Tejada, R; Keydar, I; Ramanarayanan, M; Ohno, T; Fenoglio, C; Spiegelman, S

    1978-03-01

    An antigen immunologically related to a group-specific antigen (gp52, a 52,000-dalton glycoprotein) of the mouse mammary tumor virus has been identified in paraffin sections of human breast cancers by means of the indirect immunoperoxidase technique. The specificity of the reaction with antibody against mouse mammary tumor virus was examined by absorption of the IgG with the following: (a) purified gp52; (b) a number of virus preparations (mouse mammary tumor virus, Rauscher leukemia virus, simian sarcoma virus, baboon endogenous virus, and Mason-Pfizer monkey virus); (c) normal plasma, leukocytes, breast tissue, milk, actin, collagen, and hyaluronic acid, all of human origin; (d) sheep erythrocytes and mucin. Only mouse mammary tumor virus (from C(3)H or Paris RIII strains and grown in either murine or feline cells) and purified gp52 eliminated the immunohistochemical reaction in the human breast tumors. Positive reactions were seen in 51 of 131 (39%) breast carcinomas of various histologic types, a minimal estimate in view of the limited number of sections from each tumor that could be examined. Negative reactions were obtained in all 119 benign breast lesions (cystic disease, fibroadenoma, papilloma, gynecomastia) and in all 18 normal breast tissues. With one exception, 99 carcinomas from 13 organs other than breast and 8 cystosarcomas were all negative.

  20. Lamprey VLRB response to influenza virus supports universal rules of immunogenicity and antigenicity

    Science.gov (United States)

    Altman, Meghan O; Bennink, Jack R; Yewdell, Jonathan W; Herrin, Brantley R

    2015-01-01

    Immunoglobulins (Igs) are a crown jewel of jawed vertebrate evolution. Through recombination and mutation of small numbers of genes, Igs can specifically recognize a vast variety of natural and man-made organic molecules. Jawless vertebrates evolved a parallel system of humoral immunity, which recognizes antigens not with Ig, but with a structurally unrelated receptor called the variable lymphocyte receptor B (VLRB). We exploited the convergent evolution of Ig and VLRB antibodies (Abs) to investigate if intrinsic chemical features of foreign proteins determine their antigenicity and immunogenicity. Surprisingly, we find lamprey VLRB and mouse Ig responses to influenza A virus are extremely similar. Each focuses ∼80% of the response on hemagglutinin (HA), mainly through recognition of the major antigenic sites in the HA globular head domain. Our findings predict basic conservation of Ab responses to protein antigens, strongly supporting the use of animal models for understanding human Ab responses to viruses and protein immunogens. DOI: http://dx.doi.org/10.7554/eLife.07467.001 PMID:26252514

  1. Antigenic Cartography of H9 Avian Influenza Virus and Its Application to Vaccine Selection.

    Science.gov (United States)

    Wang, Yue; Davidson, Irit; Fouchier, Ron; Spackman, Erica

    2016-05-01

    Vaccination is frequently used as a control method for the H9 subtype of low pathogenicity avian influenza virus (AIV), which is widespread in Asia and the Middle East. One of the most important factors for selecting an effective vaccine strain is the antigenic match between the hemagglutinin protein of the vaccine and the strain circulating in the field. To demonstrate the antigenic relationships among H9 AIVs, with a focus on Israeli H9 isolates, antigenic cartography was used to develop a map of H9 AIVs. Based on their antigenic diversity, three isolates from Israel were selected for vaccination-challenge studies: 1) the current vaccine virus, A/chicken/Israel/215/2007 H9N2 (Ck/215); 2) A/chicken/Israel/1163/2011 H9N2 (Ck/1163); and 3) A/ostrich/Israel/1436/2003 (Os/1436). A 50% infective dose (ID50) model was used to determine the effect of the vaccines on susceptibility to infection by using a standardized dose of vaccine. Sera collected immediately prior to challenge showed that Ck/215 was the most immunogenic, followed by Ck/1163 and Os/1436. A significant difference in ID50 was only observed with Ck/215 homologous challenge, where the ID50 was increased by 2 log 10 per bird. The ID50 for Ck/1163 was the same, regardless of vaccine, including sham vaccination. The ID50 for Os/1436 was above the maximum possible dose and therefore could not be established.

  2. Characterization of antigenic variants of hepatitis C virus in immune evasion

    Directory of Open Access Journals (Sweden)

    Hershow Ronald

    2011-07-01

    Full Text Available Abstract Background Antigenic variation is an effective way by which viruses evade host immune defense leading to viral persistence. Little is known about the inhibitory mechanisms of viral variants on CD4 T cell functions. Results Using sythetic peptides of a HLA-DRB1*15-restricted CD4 epitope derived from the non-structural (NS 3 protein of hepatitis C virus (HCV and its antigenic variants and the peripheral blood mononuclear cells (PBMC from six HLA-DRB1*15-positive patients chronically infected with HCV and 3 healthy subjects, the in vitro immune responses and the phenotypes of CD4+CD25+ cells of chronic HCV infection were investigated. The variants resulting from single or double amino acid substitutions at the center of the core region of the Th1 peptide not only induce failed T cell activation but also simultaneously up-regulate inhibitory IL-10, CD25-TGF-β+ Th3 and CD4+IL-10+ Tr1 cells. In contrast, other variants promote differentiation of CD25+TGF-β+ Th3 suppressors that attenuate T cell proliferation. Conclusions Naturally occuring HCV antigenic mutants of a CD4 epitope can shift a protective peripheral Th1 immune response into an inhibitory Th3 and/or Tr1 response. The modulation of antigenic variants on CD4 response is efficient and extensive, and is likely critical in viral persistence in HCV infection.

  3. A negative feedback modulator of antigen processing evolved from a frameshift in the cowpox virus genome.

    Directory of Open Access Journals (Sweden)

    Jiacheng Lin

    2014-12-01

    Full Text Available Coevolution of viruses and their hosts represents a dynamic molecular battle between the immune system and viral factors that mediate immune evasion. After the abandonment of smallpox vaccination, cowpox virus infections are an emerging zoonotic health threat, especially for immunocompromised patients. Here we delineate the mechanistic basis of how cowpox viral CPXV012 interferes with MHC class I antigen processing. This type II membrane protein inhibits the coreTAP complex at the step after peptide binding and peptide-induced conformational change, in blocking ATP binding and hydrolysis. Distinct from other immune evasion mechanisms, TAP inhibition is mediated by a short ER-lumenal fragment of CPXV012, which results from a frameshift in the cowpox virus genome. Tethered to the ER membrane, this fragment mimics a high ER-lumenal peptide concentration, thus provoking a trans-inhibition of antigen translocation as supply for MHC I loading. These findings illuminate the evolution of viral immune modulators and the basis of a fine-balanced regulation of antigen processing.

  4. False-positive rate of a "fourth-generation" HIV antigen/antibody combination assay in an area of low HIV prevalence.

    Science.gov (United States)

    Kim, Sinyoung; Lee, Jong-Han; Choi, Jun Yong; Kim, June Myung; Kim, Hyon-Suk

    2010-10-01

    We retrospectively analyzed the performance of the Architect HIV antigen/antibody (Ag/Ab) combination assay in a tertiary health care center with a situation of low HIV prevalence. The specificity and positive predictive value (PPV) were 99.78% and 31.21%, respectively. However, the specificity and PPV could increase to 99.99% and 89.70% using an arbitrary cutoff value.

  5. Antigenic cartography of H9N2 virus and its impact on the vaccine efficacy in chickens

    Science.gov (United States)

    The H9 subtype of avian influenza virus (AIV) is wide-spread in Asia and the Middle East. The efficacy of vaccines is enhanced by the antigenic match of the hemagglutinin protein (HA) between the vaccine and the field strain. To determine how antigenic variations affect the vaccine efficacy, speci...

  6. Molecular epidemiology of co-infection with hepatitis B virus and human immunodeficiency virus (HIV) among adult patients in Harare, Zimbabwe.

    Science.gov (United States)

    Baudi, Ian; Iijima, Sayuki; Chin'ombe, Nyasha; Mtapuri-Zinyowera, Sekesai; Murakami, Shuko; Isogawa, Masanori; Hachiya, Atsuko; Iwatani, Yasumasa; Tanaka, Yasuhito

    2017-02-01

    The objective of this study was to determine the prevalence of co-infection with hepatitis B virus (HBV) and human immunodeficiency virus (HIV) and the genetic characteristics of both viruses among pre-HIV-treatment patients in Harare, Zimbabwe. This cross-sectional survey involved 176 remnant plasma samples collected from consenting HIV patients (median age 35 [18-74]) between June and September 2014. HBV seromarkers were determined by high-sensitivity chemiluminescence assays. Molecular evolutionary analyses were conducted on the basal core promoter/precore (BCP/PC) and S regions of HBV, as well as part of the HIV pol region. Of the 176 participants (65.7% female), 19 (10.8%) were positive for HBsAg (median 0.033 IU/ml (IQR 0.01-415). The HBsAg incidence was higher in men than women (P = 0.009). HBsAg-positive subjects had lower median CD4 counts (P = 0.016). HBV DNA was detectable in 12 HBsAg-positive samples (median 3.36 log cp/ml (2.86-4.51), seven being amplified and sequenced. All isolates were subgenotype A1 without HBV drug resistance mutations but each had at least one BCP/PC mutation. PreS deletion mutants and small S antigen variants M133I/T and D144G were identified. Of the 164 HIV isolates successfully genotyped, 163 (99.4%) were HIV-1 subtype C and only one was HIV-1 subtype F1. Sixteen (9.8%) had at least one drug resistance mutation, predominantly non-nucleoside reverse transcriptase inhibitor-related mutations, observed mostly among female participants. This study shows that co-infection with HBV is present among HIV patients enrolling into HIV care in Zimbabwe, suggesting that HBV screening and monitoring programmes be strengthened in this context. J. Med. Virol. 89:257-266, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Genetic analysis and antigenic characterization of human respiratory syncytial virus group A viruses isolated in Germany 1996-2008.

    Science.gov (United States)

    Adams, Ortwin; Werzmirzowsky, Judith; Hengel, Hartmut

    2013-10-01

    The genetic and antigenic variability of 18 human respiratory syncytial virus group A viruses isolated in Germany from 1996 to 2008 was evaluated by nucleotide sequencing of the complete G and F genes and enzyme-linked immunosorbent assay analysis with anti-G and anti-F monoclonal antibodies. Phylogenetic analyses showed that the G-proteins clustered into the two genotypes GA2 and GA5. The antigenic analysis of G-gene was carried out with a panel of anti-G and anti-F monoclonal antibodies that recognized strain-specific or variable epitopes which were originally derived against long strain (subtype GA1) and MON-3-88 strain (GA2). An amino acid substitution was found in a potential O-glycosylation site leading to a loss of reactivity with a strain-specific MAb. A score was calculated for quantifying the overall reactivity of the antibodies. If reactivity of all MAbs was totalized, a net sum loss of reactivity was seen over the time suggesting that antigenic drift due to immune selection may be occurring.

  8. Evaluation of a rapid and simple fourth-generation HIV screening assay for qualitative detection of HIV p24 antigen and/or antibodies to HIV-1 and HIV-2.

    Science.gov (United States)

    Beelaert, G; Fransen, K

    2010-09-01

    The performance was assessed of a new, rapid, visual and qualitative immunoassay for the detection of HIV p24 antigen (Ag) and antibodies (Ab) to HIV-1 and HIV-2. Characterised serum or plasma specimens from patients diagnosed with HIV infection were tested: 179 samples of known Ab-positive patients harbouring different subtypes of HIV-1 (n=154) and HIV-2 (n=25) and 200 samples from individuals not infected with HIV. The assay's Ag sensitivity was assessed by testing HIV seroconversion panels (n=10) and primary HIV infection specimens (n=57). In addition, the influence of the genetic variability of HIV-1 on Ag detection was evaluated using dilutions of culture supernatants infected with different subtypes (n=50). The performance of the rapid test was compared to a "gold standard" testing algorithm with the use of a single Ag ELISA and with the Vironostika((R)) HIV Uni-Form II Ag/Ab test, a fourth-generation ELISA. The new assay, the Determine HIV-1/2 Combo demonstrated 100% (98.2-100.0) Ab specificity (200/200) and 100% (98.0-100.0) Ab sensitivity (179/179). In these samples, the observed Ag sensitivity was 86.6% (58/67) with the Determine HIV-1/2 Combo test and 92.5% (62/67) with the Vironostika compared to the reference single Ag ELISA. The assay could not detect Ag in one group O, one subtype F and two subtype H cell supernatant isolates. None of the HIV-2 Ag could be detected. Copyright 2010 Elsevier B.V. All rights reserved.

  9. Dialysis buffer with different ionic strength affects the antigenicity of cultured nervous necrosis virus (NNV) suspensions.

    Science.gov (United States)

    Gye, Hyun Jung; Nishizawa, Toyohiko

    2016-09-02

    Nervous necrosis virus (NNV) belongs to the genus Betanodavirus (Nodaviridae). It is highly pathogenic to various marine fishes. Here, we investigated the antigenicity changes of cultured NNV suspensions during 14days of dialyses using a dialysis tube at 1.4×10(4) molecular weight cut off (MWCO) in three different buffers (Dulbecco's phosphate buffered saline (D-PBS), 15mM Tris-HCl (pH 8.0), and deionized water (DIW)). Total NNV antigen titers of cultured NNV suspension varied depending on different dialysis buffers. For example, total NNV antigen titer during D-PBS dialysis was increased once but then decreased. During Tris-HCl dialysis, it was relatively stable. During dialysis in DIW, total NNV antigen titer was increased gradually. These antigenicity changes in NNV suspension might be due to changes in the aggregation state of NNV particles and/or coat proteins (CPs). ELISA values of NNV suspension changed due to changing aggregates state of NNV antigens. NNV particles in suspension were aggregated at a certain level. These aggregates were progressive after D-PBS dialysis, but regressive after Tris-HCl dialysis. The purified NNV particles self-aggregated after dialysis in D-PBS or in Tris-HCl containing 600mM NaCl, but not after dialysis in Tris-HCl or DIW. Quantitative analysis is merited to determine NNV antigens in the highly purified NNV particles suspended in buffer at low salt condition. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. 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.

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

    Science.gov (United States)

    Chiang, Cheng-Feng; Lo, Michael K; Rota, Paul A; Spiropoulou, Christina F; Rollin, Pierre E

    2010-06-03

    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. Through screening of hybridomas derived from mice immunized with gamma-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. The antigen capture ELISA developed is potentially affordable tool to provide rapid detection and differentiation between the henipaviruses.

  12. Seroprevalence of hepatitis C, hepatitis B and HIV viruses in hemophiliacs born 1985-2010 in west Azarbaijan of Iran

    Directory of Open Access Journals (Sweden)

    Nasim Valizadeh

    2013-01-01

    Full Text Available Background: Although, in the past the risk of transfusion transmitted viral infections were high in hemophilia patients, but introduction of viral inactivation methods in1985,decreased the risk of human immunodeficiency and hepatitis C and B viruses transmission significantly. The aim of study was seroprevalence of hepatitis B surface antigen (HBs Ag, hepatitis C virus antibody (HCV Ab and human immunodeficiency virus antibody (HIVAb in hemophiliacs in west Azarbaijan of Iran, born in 1985-2010. Materials and Methods: In a cross-sectional study, fifty patients with hereditary bleeding disorders born in 1985-2010, from total 250 patients who had been registered in Urmia Hemophilia Society were enrolled through the year 2010 to assess their seroprevalence for HCV Ab, HIV Ab and HBs Ag. Thirty five of 50 patients had hemophilia. Also; we performed a subset analysis for hemophilia patients. Results: All 50 patients with hereditary bleeding disorders including 35 patients with hemophilia were seronegative for HIV Ab and HBs Ag. HCV-Ab was detected in serum of 3 of 50 (6% patients with bleeding disorders. After subset analysis for hemophilia (A and B patients, we found HCV infection in 8.57% (3 of 35 of hemophiliacs. Conclusion: In this study prevalence of HCV infection was very smaller than similar studies in Iran and other countries. This study shows the safety of using viral inactivated factor concentrates and recombinant factors after year 1985.None of Hemophiliacs were seropositive for HIV Ab and HBs Ag.

  13. 21 CFR 866.3950 - In vitro human immunodeficiency virus (HIV) drug resistance genotype assay.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false In vitro human immunodeficiency virus (HIV) drug... OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3950 In vitro human immunodeficiency virus (HIV) drug resistance genotype assay. (a...

  14. Mortality in siblings of patients coinfected with HIV and hepatitis C virus

    DEFF Research Database (Denmark)

    Hansen, Ann-Brit Eg; Gerstoft, Jan; Kronborg, Gitte

    2007-01-01

    BACKGROUND: Coinfection with hepatitis C virus (HCV) is a poor prognostic factor for human immunodeficiency virus (HIV)-infected patients. We examined whether the increased mortality in these patients is partly explained by a familial excess risk of death. METHODS: Danish HIV-infected patients who...

  15. Hepatitis C and B viruses: the new opportunists in HIV infection.

    Science.gov (United States)

    Chung, Raymond T

    2006-01-01

    Coinfection with HIV accelerates disease progression in both hepatitis C virus (HCV) and hepatitis B virus (HBV) infection. Management of coinfected patients is complicated by a number of factors, including disease characteristics, drug-drug interactions, and augmented toxicity. Results of HCV and HBV treatment trials in HIV-coinfected patients and strategies for patient management are discussed herein.

  16. Antibodies elicited by influenza virus hemagglutinin fail to bind to synthetic peptides representing putative antigenic sites.

    Science.gov (United States)

    Nestorowicz, A; Tregear, G W; Southwell, C N; Martyn, J; Murray, J M; White, D O; Jackson, D C

    1985-02-01

    A number of peptides of the hemagglutinin (HA) of X-31 influenza virus have been synthesised. The amino acid sequences of some of these peptides represent regions of HA which have been postulated [Wiley et al., Nature, Lond. 289, 373-378 (1981)] to form the antigenic sites of this molecule. Animals were immunized with free peptide or peptide conjugated to a carrier and the resulting antisera examined for their capacities to bind to homologous peptide, whole HA, reduced and alkylated HA, and intact virus. Not all peptides examined in this way were immunogenic. Only antibodies raised against the C-terminus of HA1 peptide displayed binding to virus. This antiserum bound to the intact HA but not to the reduced and alkylated form of the molecule. These results raise questions as to the feasibility of using synthetic peptides of the influenza HA in short linear sequences to elicit neutralising antibody.

  17. Rapid antigen detection test for respiratory syncytial virus diagnosis as a diagnostic tool,

    Directory of Open Access Journals (Sweden)

    Flávio da Silva Mesquita

    Full Text Available Abstract Objective: The aim of this study was to evaluate the QuickVue® RSV Test Kit (QUIDEL Corp, CA, USA as a screening tool for respiratory syncytial virus in children with acute respiratory disease in comparison with the indirect immunofluorescence assay as gold standard. In Brazil, rapid antigen detection tests for respiratory syncytial virus are not routinely utilized as a diagnostic tool, except for the diagnosis of dengue and influenza. Methods: The authors retrospectively analyzed 486 nasopharyngeal aspirate samples from children under age 5 with acute respiratory infection, between December 2013 and August 2014, the samples were analyzed by indirect immunofluorescence assay and QuickVue® RSV Test kit. Samples with discordant results were analyzed by real time PCR and nucleotide sequencing. Results: From 313 positive samples by immunofluorescence assays, 282 (90% were also positive by the rapid antigen detection test, two were positive only by rapid antigen detection test, 33 were positive only by immunofluorescence assays, and 171 were positive by both methods. The 35 samples with discordant results were analyzed by real time PCR; the two samples positive only by rapid antigen detection test and the five positive only by immunofluorescence assays were also positive by real time PCR. There was no relation between the negativity by QuickVue® RSV Test and viral load or specific strain. The QuickVue® RSV Test showed sensitivity of 90%, specificity of 98.8%, predictive positive value of 99.3%, and negative predictive value of 94.6%, with accuracy of 93.2% and agreement κ index of 0.85 in comparison to immunofluorescence assay. Conclusions: This study demonstrated that the QuickVue® RSV Test Kit can be effective in early detection of Respiratory syncytial virus in nasopharyngeal aspirate and is reliable for use as a diagnostic tool in pediatrics.

  18. Rapid antigen detection test for respiratory syncytial virus diagnosis as a diagnostic tool.

    Science.gov (United States)

    Mesquita, Flávio da Silva; Oliveira, Danielle Bruna Leal de; Crema, Daniela; Pinez, Célia Miranda Nunes; Colmanetti, Thaís Cristina; Thomazelli, Luciano Matsumia; Gilio, Alfredo Elias; Vieira, Sandra Elisabeth; Martinez, Marina Baquerizo; Botosso, Viviane Fongaro; Durigon, Edison Luiz

    The aim of this study was to evaluate the QuickVue® RSV Test Kit (QUIDEL Corp, CA, USA) as a screening tool for respiratory syncytial virus in children with acute respiratory disease in comparison with the indirect immunofluorescence assay as gold standard. In Brazil, rapid antigen detection tests for respiratory syncytial virus are not routinely utilized as a diagnostic tool, except for the diagnosis of dengue and influenza. The authors retrospectively analyzed 486 nasopharyngeal aspirate samples from children under age 5 with acute respiratory infection, between December 2013 and August 2014, the samples were analyzed by indirect immunofluorescence assay and QuickVue® RSV Test kit. Samples with discordant results were analyzed by real time PCR and nucleotide sequencing. From 313 positive samples by immunofluorescence assays, 282 (90%) were also positive by the rapid antigen detection test, two were positive only by rapid antigen detection test, 33 were positive only by immunofluorescence assays, and 171 were positive by both methods. The 35 samples with discordant results were analyzed by real time PCR; the two samples positive only by rapid antigen detection test and the five positive only by immunofluorescence assays were also positive by real time PCR. There was no relation between the negativity by QuickVue® RSV Test and viral load or specific strain. The QuickVue® RSV Test showed sensitivity of 90%, specificity of 98.8%, predictive positive value of 99.3%, and negative predictive value of 94.6%, with accuracy of 93.2% and agreement κ index of 0.85 in comparison to immunofluorescence assay. This study demonstrated that the QuickVue® RSV Test Kit can be effective in early detection of Respiratory syncytial virus in nasopharyngeal aspirate and is reliable for use as a diagnostic tool in pediatrics. Copyright © 2016 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  19. Virological Determinants of Spontaneous Postpartum e Antigen Seroconversion and Surface Antigen Seroclearance in Pregnant Women Infected with Hepatitis B Virus.

    Science.gov (United States)

    Hu, Yali; Feng, Zhenhua; Liu, Jingli; Chen, Jie; Zhang, Shu; Zhou, Yi-Hua

    2016-04-01

    We investigated the virological factors predicting spontaneous postpartum hepatitis B e antigen (HBeAg) seroconversion and hepatitis B surface antigen (HBsAg) seroclearance in pregnant women infected with hepatitis B virus (HBV). We invited 419 HBV infected women whose sera had been collected during their pregnancy from August 2002-July 2004 and archived at -30°C, to participate the follow-up in October 2009-March 2010. Various virological factors were determined and compared in women with or without the seroconversion and seroclearance. A total of 264 (63.0%) antiviral naive women participated in the follow-up with an average observation period of 6.4 years (5.4-7.4). Of 76 women who were HBeAg positive during pregnancy, 42 (55.3%) seroconverted to anti-HBe during follow-up. Compared to pregnant women with HBV DNA ≥3 × 10(7) IU/mL or HBeAg ≥770 S/CO, those with HBV DNA women cleared HBsAg; pregnant women with HBsAg levels of 100-999 and 1000 IU/mL. HBeAg-positive pregnant women with HBV DNA <3 × 10(7) IU/mL or HBeAg <770 S/CO are more likely to undergo postpartum HBeAg seroconversion. HBsAg <100 IU/mL is a strong predictor of spontaneous postpartum HBsAg seroclearance. Copyright © 2016 IMSS. Published by Elsevier Inc. All rights reserved.

  20. Antigenic structure of the nucleocapsid protein of porcine reproductive and respiratory syndrome virus.

    Science.gov (United States)

    Wootton, S K; Nelson, E A; Yoo, D

    1998-11-01

    A collection of 12 monoclonal antibodies (MAbs) raised against porcine reproductive and respiratory syndrome (PRRS) virus was used to study the antigenic structure of the virus nucleocapsid protein (N). The full-length N gene, encoded by open reading frame 7, was cloned from the Canadian PRRS virus, PA-8. Deletions were introduced into the N gene to produce a series of nine overlapping protein fragments ranging in length from 25 to 112 amino acids. The individual truncated genes were cloned as glutathione S-transferase fusions into a eukaryotic expression vector downstream of the T7 RNA polymerase promoter. HeLa cells infected with recombinant vaccinia virus expressing T7 RNA polymerase were transfected with plasmid DNA encoding the N protein fragments, and the antigenicity of the synthesized proteins was analyzed by immunoprecipitation. Based on the immunoreactivities of the N protein deletion mutants with the panel of N-specific MAbs, five domains of antigenic importance were identified. MAbs SDOW17, SR30, and 5H2.3B12.1C9 each identified independent domains defined by amino acids 30 to 52, 69 to 123, and 37 to 52, respectively. Seven of the MAbs tested specifically recognized the local protein conformation formed in part by the amino acid residues 52 to 69. Furthermore, deletion of 11 amino acids from the carboxy terminus of the nucleocapsid protein disrupted the epitope configuration recognized by all of the conformation-dependent MAbs, suggesting that the carboxy-terminal region plays an important role in maintaining local protein conformation.

  1. Specificity of two HIV screening tests detecting simultaneously HIV-1 p24 antigen and antibodies to HIV-1 and -2.

    Science.gov (United States)

    Blaich, Annette; Buser, Andreas; Stöckle, Marcel; Gehringer, Christian; Hirsch, Hans H; Battegay, Manuel; Klimkait, Thomas; Frei, Reno

    2017-11-01

    This study aimed at assessing the specificity of the Elecsys® HIV combi PT in comparison to the ARCHITECT® HIV Ag/Ab Combo. With both of these assays, 3997 unselected sera from patients of a tertiary health care centre in Basel, Switzerland, were screened for HIV. Reactive sera were reanalysed on the VIDAS® HIV Duo Ultra to identify false-reactive specimens prior to confirmation by quantitative PCR and line immunoassay. The Elecsys® compared to the ARCHITECT® shows a similar specificity (99.7% versus 99.8%) but a slightly lower positive predictive value (71.8% versus 80%). Samples tested with a cut-off index (COI) between 0.91 and 4.85 (cut-off false-reactive. There was no false-reactive result with the VIDAS®. Of the false-reactive samples, 66.7% could be related to patient-specific underlying conditions. The HIV two-tiered diagnostic algorithm proposed in this work improved the positive predictive values of the Elecsys® or ARCHITECT® to 100% when the results of the VIDAS® were included. Values just above the cut-off are highly suspicious to be false-reactive and high COI or S/CO ratios are associated with true positivity. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Surgical excision for recurrent herpes simplex virus 2 (HSV-2) anogenital infection in a patient with human immunodeficiency virus (HIV).

    Science.gov (United States)

    Arinze, Folasade; Shaver, Aaron; Raffanti, Stephen

    2017-10-01

    Recurrent anogenital herpes simplex virus infections are common in patients with human immunodeficiency virus (HIV), of whom approximately 5% develop resistance to acyclovir. We present a case of a 49-year-old man with HIV who had an 8-year history of recurrent left inguinal herpes simplex virus type 2 ulcerations. He initially responded to oral acyclovir, but developed resistance to acyclovir and eventually foscarnet. The lesion progressed to a large hypertrophic mass that required surgical excision, which led to resolution without recurrences. Our case highlights the importance of surgical excision as a treatment option in refractory herpes simplex virus anogenital infections.

  3. Atypical presentations of genital herpes simplex virus in HIV-1 and HIV-2 effectively treated by imiquimod.

    Science.gov (United States)

    McKendry, Anna; Narayana, Srinivasulu; Browne, Rita

    2015-05-01

    Atypical presentations of genital herpes simplex virus have been described in HIV. We report two cases with hypertrophic presentations which were effectively treated with imiquimod, one of which is the first reported case occurring in a patient with HIV-2. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  4. Hepatitis B surface antigen concentrations in patients with HIV/HBV co-infection.

    Directory of Open Access Journals (Sweden)

    Jerzy Jaroszewicz

    Full Text Available HBsAg clearance is associated with clinical cure of chronic hepatitis B virus (HBV infection. Quantification of HBsAg may help to predict HBsAg clearance during the natural course of HBV infection and during antiviral therapy. Most studies investigating quantitative HBsAg were performed in HBV mono-infected patients. However, the immune status is considered to be important for HBsAg decline and subsequent HBsAg loss. HIV co-infection unfavorably influences the course of chronic hepatitis B. In this cross-sectional study we investigated quantitative HBsAg in 173 HBV/HIV co-infected patients from 6 centers and evaluated the importance of immunodeficiency and antiretroviral therapy. We also compared 46 untreated HIV/HBV infected patients with 46 well-matched HBV mono-infected patients. HBsAg levels correlated with CD4 T-cell count and were higher in patients with more advanced HIV CDC stage. Patients on combination antiretroviral therapy (cART including nucleos(tide analogues active against HBV demonstrated significant lower HBsAg levels compared to untreated patients. Importantly, HBsAg levels were significantly lower in patients who had a stronger increase between nadir CD4 and current CD4 T-cell count during cART. Untreated HIV/HBV patients demonstrated higher HBsAg levels than HBV mono-infected patients despite similar HBV DNA levels. In conclusion, HBsAg decline is dependent on an effective immune status. Restoration of CD4 T-cells during treatment with cART including nucleos(tide analogues seems to be important for HBsAg decrease and subsequent HBsAg loss.

  5. Simultaneous presence of endogenous retrovirus and herpes virus antigens has profound effect on cell-mediated immune responses

    DEFF Research Database (Denmark)

    Brudek, Tomasz; Christensen, Tove; Hansen, Hans Jacob

    2004-01-01

    Retroviruses have been suggested as possible pathogenic factors in multiple sclerosis (MS), supported by the observation that endogenous retroviruses are activated in MS patients. Different members of the herpes family of which several are neurotropic have also been suggested as factors in MS...... pathogenesis. Further, interactions between retroviruses and herpes viruses have been implied in the development of MS. The objective of the study was investigation of cell-mediated immune responses of MS patients to retrovirus and herpes virus antigens, particularly antigen combinations, with analyses...... retrovirus HERV-H and herpes virus antigens resulted in highly increased cellular immune responses among both the MS patients and healthy subjects. The increase was synergistic in character in most samples. Very pronounced effects were obtained using HHV-6A and HSV-1 antigens. Blast transformation assays...

  6. T-cell subset alterations and lymphocyte responsiveness to mitogens and antigen during severe primary infection with HIV: a case series of seven consecutive HIV seroconverters

    DEFF Research Database (Denmark)

    Pedersen, C; Dickmeiss, E; Gaub, J

    1990-01-01

    Seven consecutive patients who presented with a severe acute mononucleosis-like illness associated with HIV seroconversion were evaluated by T-cell subset enumerations and measurements of lymphocyte transformation responses to mitogens and antigen during both their primary illness and a 1-year...

  7. Antigenic profile of African horse sickness virus serotype 4 VP5 and identification of a neutralizing epitope shared with bluetongue virus and epizootic hemorrhagic disease virus

    DEFF Research Database (Denmark)

    Martinez-Torrecuadrada, J.L.; Langeveld, J.P.M.; Venteo, A.

    1999-01-01

    African horse sickness virus (AHSV) causes a fatal disease in horses. The virus capsid is composed of a double protein layer, the outermost of which is formed by two proteins: VP2 and VP5. VP2 is known to determine the serotype of the virus and to contain the neutralizing epitopes. The biological...... function of VP5, the other component of the capsid, is unknown. In this report, AHSV VP5, expressed in insect cells alone or together with VP2, was able to induce AHSV-specific neutralizing antibodies. Moreover, two VP5-specific monoclonal antibodies (MAbs) that were able to neutralize the virus...... in a plaque reduction assay were generated. To dissect the antigenic structure of AHSV VP5, the protein was cloned in Escherichia coil using the pET3 system. The immunoreactivity of both MAbs, and horse and rabbit polyclonal antisera, with 17 overlapping fragments from VP5 was analyzed. The most...

  8. Persistent HIV antigenaemia and decline of HIV core antibodies associated with transition to AIDS

    NARCIS (Netherlands)

    Lange, J. M.; Paul, D. A.; Huisman, H. G.; de Wolf, F.; van den Berg, H.; Coutinho, R. A.; Danner, S. A.; van der Noordaa, J.; Goudsmit, J.

    1986-01-01

    Sequential serum samples from 13 homosexual men who seroconverted for antibodies to human immunodeficiency virus (HIV) were tested for HIV antigen. In one of these men, who developed the acquired immune deficiency syndrome (AIDS), HIV antigenaemia preceded the onset of AIDS by more than a year and

  9. Performance evaluation of the Bio-Rad Laboratories GS HIV Combo Ag/Ab EIA, a 4th generation HIV assay for the simultaneous detection of HIV p24 antigen and antibodies to HIV-1 (groups M and O) and HIV-2 in human serum or plasma.

    Science.gov (United States)

    Bentsen, Christopher; McLaughlin, Lisa; Mitchell, Elizabeth; Ferrera, Carol; Liska, Sally; Myers, Robert; Peel, Sheila; Swenson, Paul; Gadelle, Stephane; Shriver, M Kathleen

    2011-12-01

    A multi-center study was conducted to evaluate the Bio-Rad GS HIV Combo Ag/Ab EIA, a 4th generation HIV-1/HIV-2 assay for the simultaneous detection of HIV p24 antigen and antibodies to HIV-1 (groups M and O) and HIV-2 in human serum or plasma in adult and pediatric populations. The objectives of the study were to assess assay performance for the detection of acute HIV infections; sensitivity in known HIV positive samples; percent agreement with HIV status; specificity in low and high risk individuals of unknown HIV status; and to compare assay performance to a 3rd generation HIV assay. The evaluation included testing 9150 samples at four U.S. clinical trial sites, using three kit lots. Unlinked samples were from routine testing, repositories or purchased from vendors. GS HIV Combo Ag/Ab EIA detection in samples from individuals in two separate populations with acute HIV infection was 95.2% (20/21) and 86.4% (38/44). Sensitivity was 100% (1603/1603) in known antibody positive [HIV-1 Groups M and O, and HIV-2] samples. HIV p24 antigen detection was 100% (53/53) in HIV-1 culture supernatants. HIV-1 seroconversion panel detection improved by a range of 0-20 days compared to a 3rd generation HIV test. Specificity was 99.9% (5989/5996) in low risk, 99.9% (959/960) in high risk and 100% (100/100) in pediatric populations. The GS HIV Combo Ag/Ab EIA significantly reduced the diagnostic window when compared to the 3rd generation screening assay, enabling earlier diagnosis of HIV infection. The performance parameters of the Bio-Rad GS HIV Combo Ag/Ab EIA are well suited for use in HIV diagnostic settings. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Validation of ELISA for the detection of African horse sickness virus antigens and antibodies.

    Science.gov (United States)

    Rubio, C; Cubillo, M A; Hooghuis, H; Sanchez-Vizcaino, J M; Diaz-Laviada, M; Plateau, E; Zientara, S; Crucière, C; Hamblin, C

    1998-01-01

    The mortality rate in susceptible populations of horses during an epizootic of African horse sickness (AHS) may be in excess of 90%. Rapid and reliable assays are therefore essential for the confirmation of clinical diagnoses and to enable control strategies to be implemented without undue delay. One of the major objectives of a recent European Union funded project was the validation of newly developed diagnostic assays which are rapid, sensitive, highly reproducible and inexpensive, for the detection of African horse sickness virus (AHSV) antigens and antibodies. The Laboratorio de Sanidad y Produccion Animal (LSPA) in Algete, Spain was charged with the responsibility of co-ordinating and supplying samples of viruses and antisera to the participating laboratories in Spain, France and the United Kingdom. The panels comprised 76 antigen samples for assay by indirect sandwich ELISAs and 53 serum samples for antibody detection by either indirect or competitive ELISAs. Results generated by ELISA for each laboratory were analysed in LSPA in terms of their relative sensitivities and specificities. There was a good agreement between the ELISAs used for either antigen or antibody detection. The participating groups agreed that any field sample giving a doubtful result would always be retested by ELISA and an alternative assay.

  11. Two conditional tsA mutant simian virus 40 T antigens display marked differences in thermal inactivation.

    OpenAIRE

    Reynisdóttir, I; Prives, C

    1992-01-01

    We have characterized the simian virus 40 (SV40) origin-containing DNA (ori-DNA) replication functions of two SV40 conditional mutant T antigens: tsA438 A-V (tsA58) and tsA357 R-K (tsA30). Both tsA mutant T antigens, immunopurified from recombinant baculovirus-infected insect cells, mediated replication of SV40 ori-DNA in vitro to similar extents as did wild-type T antigen in reactions at 33 degrees C. However, at 41 degrees C, the restrictive temperature, while tsA438 T antigen still generat...

  12. Involvement of lymphocyte function-associated antigen-1 (LFA-1) in HIV infection: inhibition by monoclonal antibody

    DEFF Research Database (Denmark)

    Hansen, J E; Nielsen, C; Mathiesen, Lars Reinhardt

    1991-01-01

    Monoclonal antibodies (MAbs) against the alpha- and beta-chain of lymphocyte-associated antigen-1 (LFA-1) were examined for inhibition of HIV-1 infection in vitro. Infection of the T cell line MT4 and the monocytic cell line U937 by isolates HTLVIIIB and SSI-002, respectively was inhibited...

  13. The Human Immune Response to HIV and its Impact in the Potential Development of an Inactivated HIV Vaccine.

    Science.gov (United States)

    Rios, Adan; Pottet, Ethan C; Siwak, Edward B; Anderson, Dallas W; Yao, Qizhi C

    2016-01-01

    There is evidence that the transmission and acute phase of HIV infection triggers an immune response capable of controlling HIV subverted by the process of virus integration, essential to the replicative cycle of retroviruses. We review here two aspects that deserve consideration in light of recent developments concerning HIV transmission and vaccine development: vaccines directed against transmitted/founder viruses, and a reconsideration of inactivation as a viable means to obtain a preventive HIV vaccine. Since 80% of sexually transmitted HIV infections are caused by a single transmitted/founder variant, it is appropriate to target transmitted/founder viruses for vaccine development. Transmitted/founder virus transmission is subject to strong natural selection based on conserved signatures present in all forms of transmitted/founder HIV viruses. This provides an opportunity to pursue inactivation methods of vaccine development that allow antigenic preservation of HIV transmitted/founder viruses. The presentation to the immune system of an inactivated but antigenically preserved transmitted/founder virus should allow the development of an effective immune response against transmitted/founder viruses. This could be the base for an inactivated transmitted/founder virus HIV vaccine. We have devised a method of inactivation of HIV reverse transcriptase through the use of a novel photo-labeling procedure based on the use of photo-labeled analogs of antiretroviral compounds with specific affinity for HIV reverse transcriptase. We believe this method fulfills the required conditions for an effective preventive vaccine development: inactivation and antigenic preservation.

  14. Structure-guided evolution of antigenically distinct adeno-associated virus variants for immune evasion.

    Science.gov (United States)

    Tse, Longping Victor; Klinc, Kelli A; Madigan, Victoria J; Castellanos Rivera, Ruth M; Wells, Lindsey F; Havlik, L Patrick; Smith, J Kennon; Agbandje-McKenna, Mavis; Asokan, Aravind

    2017-06-13

    Preexisting neutralizing antibodies (NAbs) against adeno-associated viruses (AAVs) pose a major, unresolved challenge that restricts patient enrollment in gene therapy clinical trials using recombinant AAV vectors. Structural studies suggest that despite a high degree of sequence variability, antibody recognition sites or antigenic hotspots on AAVs and other related parvoviruses might be evolutionarily conserved. To test this hypothesis, we developed a structure-guided evolution approach that does not require selective pressure exerted by NAbs. This strategy yielded highly divergent antigenic footprints that do not exist in natural AAV isolates. Specifically, synthetic variants obtained by evolving murine antigenic epitopes on an AAV serotype 1 capsid template can evade NAbs without compromising titer, transduction efficiency, or tissue tropism. One lead AAV variant generated by combining multiple evolved antigenic sites effectively evades polyclonal anti-AAV1 neutralizing sera from immunized mice and rhesus macaques. Furthermore, this variant displays robust immune evasion in nonhuman primate and human serum samples at dilution factors as high as 1:5, currently mandated by several clinical trials. Our results provide evidence that antibody recognition of AAV capsids is conserved across species. This approach can be applied to any AAV strain to evade NAbs in prospective patients for human gene therapy.

  15. Detection of chikungunya virus antigen by a novel rapid immunochromatographic test.

    Science.gov (United States)

    Okabayashi, Tamaki; Sasaki, Tadahiro; Masrinoul, Promsin; Chantawat, Nantarat; Yoksan, Sutee; Nitatpattana, Narong; Chusri, Sarunyou; Morales Vargas, Ronald E; Grandadam, Marc; Brey, Paul T; Soegijanto, Soegeng; Mulyantno, Kris Cahyo; Churrotin, Siti; Kotaki, Tomohiro; Faye, Oumar; Faye, Ousmane; Sow, Abdourahmane; Sall, Amadou Alpha; Puiprom, Orapim; Chaichana, Panjaporn; Kurosu, Takeshi; Kato, Seiji; Kosaka, Mieko; Ramasoota, Pongrama; Ikuta, Kazuyoshi

    2015-02-01

    Chikungunya fever is a mosquito-borne disease of key public health importance in tropical and subtropical countries. Although severe joint pain is the most distinguishing feature of chikungunya fever, diagnosis remains difficult because the symptoms of chikungunya fever are shared by many pathogens, including dengue fever. The present study aimed to develop a new immunochromatographic diagnosis test for the detection of chikungunya virus antigen in serum. Mice were immunized with isolates from patients with Thai chikungunya fever, East/Central/South African genotype, to produce mouse monoclonal antibodies against chikungunya virus. Using these monoclonal antibodies, a new diagnostic test was developed and evaluated for the detection of chikungunya virus. The newly developed diagnostic test reacted with not only the East/Central/South African genotype but also with the Asian and West African genotypes of chikungunya virus. Testing of sera from patients suspected to have chikungunya fever in Thailand (n = 50), Laos (n = 54), Indonesia (n = 2), and Senegal (n = 6) revealed sensitivity, specificity, and real-time PCR (RT-PCR) agreement values of 89.4%, 94.4%, and 91.1%, respectively. In our study using serial samples, a new diagnostic test showed high agreement with the RT-PCR within the first 5 days after onset. A rapid diagnostic test was developed using mouse monoclonal antibodies that react with chikungunya virus envelope proteins. The diagnostic accuracy of our test is clinically acceptable for chikungunya fever in the acute phase. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  16. Is response to anti-hepatitis C virus treatment predictive of mortality in hepatitis C virus/HIV-positive patients?

    DEFF Research Database (Denmark)

    Peters, Lars; Raben, Dorthe

    2017-01-01

    BACKGROUND: Long-term clinical outcomes after hepatitis C virus (HCV) treatment of HIV/HCV patients are not well described. We aimed to compare the risk of all-cause and liver-related death (LRD) according to HCV treatment response in HIV/HCV patients in the multicohort study Collaboration...

  17. Histoplasmosis in Patients With Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome (HIV/AIDS)

    Science.gov (United States)

    Anderson, Albert M.; Sanchez, Alejandro; Farabi, Alireza; Hage, Chadi; Baddley, John W.; Jhaveri, Malhar; Greenberg, Richard N.; Bamberger, David M.; Rodgers, Mark; Crawford, Timothy N.; Wheat, L. Joseph

    2014-01-01

    Abstract Although discontinuation of suppressive antifungal therapy for acquired immunodeficiency syndrome (AIDS)-associated histoplasmosis is accepted for patients with immunologic recovery, there have been no published studies of this approach in clinical practice, and minimal characterization of individuals who relapse with this disease. We performed a multicenter retrospective cohort study to determine the outcome in AIDS patients following discontinuation of suppressive antifungal therapy for histoplasmosis. Ninety-seven patients were divided into a physician-discontinued suppressive therapy group (PD) (38 patients) and a physician-continued suppressive therapy group (PC) (59 patients). The 2 groups were not statistically different at baseline, but at discontinuation of therapy and at the most recent follow-up there were significant differences in adherence to therapy, human immunodeficiency virus (HIV) RNA, and urinary Histoplasma antigen concentration. There was no relapse or death attributed to histoplasmosis in the PD group compared with 36% relapse (p 150 cells/mL, HIV RNA <400 c/mL, Histoplasma antigenuria <2 ng/mL (equivalent to <4.0 units in second-generation method), and no CNS histoplasmosis. PMID:24378739

  18. [False positive results of HIV virus tests in patients undergoing chronic hemodialysis].

    Science.gov (United States)

    Ujhelyi, E; Gál, G; Makó, J; Füst, G; Büki, B; Nagy, K; Ferenc, D T; Dietrich, M P; Hengster, P; Mayer, V

    1989-01-08

    The sera of 173 haemodialysis patients treated in two dialysis centers in Hungary were tested for the presence of HIV (HTLV III/LAV) antibodies. Four different commercial enzyme immunoassay (EIA) kits and two types (CEM/LAV, and H9/HTLV III) of indirect immunofluorescence assay (IFA) were used. The Western blot technique was applied as confirmatory test in the study. No confirmed positive results were found in any of the cases. However, in 15 patients (8.7%) false positive (not confirmable by the Western blot assay) results were obtained in at least one but mostly in all of the three type 1 EIA kits (ORGANON, ELECTRONUCLEONICS, SORIN) applied. In 4 patients, the IFA assay also gave false positive results which could be repeated in sequential samples taken from the same patients. Increased reactivity in the control plate (coated with a concentrate of cellular material shed by uninfected H9 cell line) of the SORIN kit was found only in a few false positive samples and no fluorescence with the uninfected H9 or CEM cells was observed in any of the sera showing a false positive IFA. These results indicate that the false positive anti-HIV results frequently observable in haemodialysis patients are not simply the consequence of the presence of antibodies reacting with the uninfected H9 and/or CEM cells but they are most probably due to antibodies against antigens expressed on these cells only after infection with the human immunodeficiency virus.

  19. epidemiology of hepatitis b and hepatitis c virus infections among hiv

    African Journals Online (AJOL)

    boaz

    MO, Mohammed BET. HBV, HCV and HIV. Among Patients with Hemophilia in. Khartoum-Sudan. S J Med Sci. 2011; 6(4): 51-. 56. 23) Mederacke I, Potthoff A, Meyer-Olson D,. Meier M, Raupach R, Manns MP et al. HCV core antigen testing in HIV and HBV co- infected patients and in HCV infected patients on Hemodialysis.

  20. Male circumcision wound healing in human immunodeficiency virus (HIV)-negative and HIV-positive men in Rakai, Uganda.

    Science.gov (United States)

    Kigozi, Godfrey; Musoke, Richard; Kighoma, Nehemiah; Watya, Stephen; Serwadda, David; Nalugoda, Fred; Kiwanuka, Noah; Nkale, James; Wabwire-Mangen, Fred; Makumbi, Frederick; Sewankambo, Nelson K; Gray, Ronald H; Wawer, Maria J

    2014-01-01

    To assess completed wound healing after medical male circumcision (MMC) among human immunodeficiency virus (HIV)-negative and HIV-positive men with cluster of differentiation 4 (CD4) counts of HIV-positive men with low CD4 counts. In all, 262 HIV-negative and 177 HIV-positive consenting males aged ≥12 years accepted MMC using the dorsal slit procedure and were enrolled in the study. Socio-demographic and behavioural data and blood for HIV testing and CD4 counts were collected at baseline. Participants were followed weekly to collect information on resumption of sex, condom use and both self-reported and clinically assessed wound healing. The proportions healed among HIV-positive men were compared with HIV-negative men. Time to complete wound healing was assessed by Kaplan-Meier survival analysis. There were no statistically significant differences in the proportion of men healed by HIV status. At 4 weeks, the proportions healed were 85.9% in HIV-negative men, 77.4% in HIV-positive men with a CD4 count of ≥350 cells/mm(3) and 87.1% in HIV-positive men with a CD4 count of healing was 4 weeks and did not vary by HIV or CD4 status. All men had certified complete wound healing at 6 weeks after MMC. In all, 1.4% of HIV-positive men with a CD4 count of healing, compared with 8.5% among HIV-positive men with a CD4 count of ≥350 cells/mm(3) (P = 0.052) and 7.8% (P = 0.081) among HIV-negative men. Inclusion of HIV-positive men with low CD4 counts in MMC services is not deleterious to postoperative wound healing. © 2013 The Authors. BJU International © 2013 BJU International.

  1. Prevalence of autoantibodies against cellular antigens in patients with HIV and leprosy coinfection in the Amazon region.

    Science.gov (United States)

    Bichara, Clea Nazaré Carneiro; Bichara, Carlos David Araújo; Tostes, Camila; Povoa, Marinete Marins; Quaresma, Juarez Antonio Simões; Xavier, Marília Brasil

    2017-06-01

    Infectious agents can activate self-reactive T cells. In general, infections trigger various mechanisms, including a lack of auto-tolerance, induction of costimulatory molecules on antigen presenting cells, and molecular simulation, in addition to cross-reactions between microbial antigens and self-antigens. HIV and leprosy coinfections lead to self-immunity with the production of autoantibodies. However, not enough data on the immune behaviour associated with this coinfection are available. Therefore, this study focused on the detection of autoantibodies against cellular antigens (AACA) in individuals with HIV and leprosy coinfection in the Amazon region. Patients were distributed into four groups according to their infections: (i) coinfection with HIV and leprosy (n = 23), (ii) infection with leprosy (n = 33), (iii) infection with HIV/AIDS (n = 25), and (iv) healthy blood donor controls (n = 100). AACA were identified by indirect immunofluorescence and the samples were tested using a commercial diagnosis kit containing the antinuclear antibody HEp-2. Morphologically, all stages of cell division were assessed in addition to the morphological features associated with the nuclear matrix, nucleolus, mitotic spindle, and cytoplasm. There was a high prevalence of AACA in the coinfection group (47.8%, n = 11) when compared with the control group of healthy blood donors (2.0%). The results showed predominantly cytoplasmic staining in all groups analysed, and no difference was observed between the presence or absence of AACA and the leprosy forms (paucibacillary and multibacillary) in the coinfection group. The results of this study show that despite the tendency of coinfected patients to have higher levels of autoantibodies, no correlation was observed between clinical and laboratorial variables and morbidity associated with HIV and leprosy coinfections or the levels of AACA in the serum of coinfected patients. These data are important to elucidate

  2. Conditional live virus as a novel approach towards a safe live attenuated HIV vaccine

    NARCIS (Netherlands)

    Das, Atze T.; Zhou, Xue; Vink, Monique; Klaver, Bep; Berkhout, Ben

    2002-01-01

    To control the worldwide spread of HIV, a safe and effective prophylactic vaccine is urgently needed. Studies with the simian immunodeficiency virus demonstrated that a live attenuated virus can be effective as a vaccine, but serious concerns about the safety of such a vaccine virus have arisen. We

  3. Longitudinal microarray analysis of cell surface antigens on peripheral blood mononuclear cells from HIV+ individuals on highly active antiretroviral therapy

    Directory of Open Access Journals (Sweden)

    Wang Bin

    2008-03-01

    Full Text Available Abstract Background The efficacy of highly active antiretroviral therapy (HAART determined by simultaneous monitoring over 100 cell-surface antigens overtime has not been attempted. We used an antibody microarray to analyze changes in the expression of 135 different cell-surface antigens overtime on PBMC from HIV+ patients on HAART. Two groups were chosen, one (n = 6 achieved sustainable response by maintaining below detectable plasma viremia and the other (n = 6 responded intermittently. Blood samples were collected over an average of 3 years and 5–8 time points were selected for microarray assay and statistical analysis. Results Significant trends over time were observed for the expression of 7 cell surface antigens (CD2, CD3epsilon, CD5, CD95, CD36, CD27 and CD28 for combined patient groups. Between groups, expression levels of 10 cell surface antigens (CD11a, CD29, CD38, CD45RO, CD52, CD56, CD57, CD62E, CD64 and CD33 were found to be differential. Expression levels of CD9, CD11a, CD27, CD28 and CD52, CD44, CD49d, CD49e, CD11c strongly correlated with CD4+ and CD8+ T cell counts, respectively. Conclusion Our findings not only detected markers that may have potential prognostic/diagnostic values in evaluating HAART efficacy, but also showed how density of cell surface antigens could be efficiently exploited in an array-like manner in relation to HAART and HIV-infection. The antigens identified in this study should be further investigated by other methods such as flow cytometry for confirmation as biological analysis of these antigens may help further clarify their role during HAART and HIV infection.

  4. Chikungunya Virus Infection and Acute Elevation of Serum Prostate-Specific Antigen

    Directory of Open Access Journals (Sweden)

    William Derval Aiken

    2015-01-01

    Full Text Available A man with prostate cancer on a regime of active surveillance had a laboratory-confirmed acute Chikungunya virus infection. The patient experienced a sudden increase in serum Prostate-Specific Antigen (PSA during the acute illness that caused him anxiety and confounded interpretation of the PSA test. Six weeks after the onset of Chikungunya Fever symptoms, the elevated serum PSA returned to baseline. The association of Chikungunya Fever and elevated serum PSA may result in misinterpretation of the PSA test, triggering unnecessary prostate biopsy or other management errors.

  5. Beta 2-microglobulin, HIV-1 p24 antibody and acid-dissociated HIV-1 p24 antigen levels: predictive markers for vertical transmission of HIV-1 in pregnant Ugandan women.

    Science.gov (United States)

    Jackson, J B; Kataaha, P; Hom, D L; Mmiro, F; Guay, L; Ndugwa, C; Marum, L; Piwowar, E; Brewer, K; Toedter, G

    1993-11-01

    To evaluate the clinical utility of plasma beta 2-microglobulin (beta 2M) levels, acid-dissociated HIV-1 p24 antigen, and HIV-1 p24-antibody titers in predicting HIV-1 vertical transmission in 227 HIV-1-infected Ugandan pregnant women. Plasma beta 2M levels, acid-dissociated HIV-1 p24-antigen positivity, and HIV-1 p24-antibody titers were determined using commercial enzyme immunoassays (EIA) in a Ugandan cohort of 52 HIV-1-seropositive transmitting mothers, 175 HIV-1-seropositive non-transmitting mothers, and 52 seronegative mothers within 6 weeks prior to delivery. Transmitter mothers had significantly higher plasma concentrations of beta 2M (1.80 +/- 1.13 mg/l) than non-transmitter seropositive mothers (1.32 +/- 0.81 mg/l; P = 0.0013). Similarly, a significantly higher proportion of transmitter mothers had detectable p24 antigen than non-transmitter mothers [six out of 51 (11.8%) versus six out of 173 (3.5%); P = 0.03]. Compared with the vertical transmission rate of 23% in the seropositive group, the positive predictive values of a beta 2M level > 1.5 mg/l or detectable HIV-1 p24 antigen for vertical transmission were 34 and 50%, respectively. Five of six (83.3%) seropositive mothers with both a beta 2M level > 1.5 mg/l and detectable p24 antigenemia transmitted HIV-1 infection to their infants compared with 25 of 124 (20.2%) seropositive mothers with values below the cut-off values for both tests (P = 0.00249). However, beta 2M was not found to be a significant independent predictor of vertical transmission when analyzed in a multivariate model with p24 antigenemia. There was no significant difference in HIV-1 p24-antibody titers in transmitter mothers versus non-transmitter mothers (P = 0.299). beta 2M levels and acid-dissociated HIV-1 p24-antigen assays may be used to predict which HIV-1-infected pregnant women are at greatest risk for vertical transmission. However, only the p24-antigen test was independently predictive of vertical transmission and its

  6. Frequency of human immunodeficiency virus type-2 in hiv infected patients in Maputo City, Mozambique

    Directory of Open Access Journals (Sweden)

    Bhatt Nilesh

    2011-08-01

    Full Text Available Abstract The HIV/AIDS pandemic is primarily caused by HIV-1. Another virus type, HIV-2, is found mainly in West African countries. We hypothesized that population migration and mobility in Africa may have facilitated the introduction and spreading of HIV-2 in Mozambique. The presence of HIV-2 has important implications for diagnosis and choice of treatment of HIV infection. Hence, the aim of this study was to estimate the prevalence of HIV-2 infection and its genotype in Maputo, Mozambique. HIV-infected individuals (N = 1,200 were consecutively enrolled and screened for IgG antibodies against HIV-1 gp41 and HIV-2 gp36 using peptide-based enzyme immunoassays (pepEIA. Specimens showing reactivity on the HIV-2 pepEIA were further tested using the INNO-LIA immunoblot assay and HIV-2 PCR targeting RT and PR genes. Subtype analysis of HIV-2 was based on the protease gene. After screening with HIV-2 pepEIA 1,168 were non-reactive and 32 were reactive to HIV-2 gp36 peptide. Of this total, 30 specimens were simultaneously reactive to gp41 and gp36 pepEIA while two samples reacted solely to gp36 peptide. Only three specimens containing antibodies against gp36 and gp105 on the INNO-LIA immunoblot assay were found to be positive by PCR to HIV-2 subtype A. The proportion of HIV-2 in Maputo City was 0.25% (90%CI 0.01-0.49. The HIV epidemic in Southern Mozambique is driven by HIV-1, with HIV-2 also circulating at a marginal rate. Surveillance program need to improve HIV-2 diagnosis and consider periodical survey aiming to monitor HIV-2 prevalence in the country.

  7. HIV

    African Journals Online (AJOL)

    Introduction. The·human immunodeficiency virus (HIV) can be transmiHed from one person to onother through the use of non-sterile nee- dles, syringes, and other skin-piercing and invasive instruments. Proper .sterilization of all such instruments is therefore important to prevent its transmission. HIV is very sensitive to ...

  8. A hunter virus that targets both infected cells and HIV free virions: Implications for therapy

    Directory of Open Access Journals (Sweden)

    Greer Cody

    2012-12-01

    Full Text Available Abstract The design of ‘hunter’ viruses aimed at destroying human immunodeficiency virus (HIV infected cells is an active area of research that has produced promising results in vitro. Hunters are designed to target exposed viral envelope proteins in the membranes of infected cells, but there is evidence that the hunter may also target envelope proteins of free HIV, inducing virus-virus fusion. In order to predict the effects of this fusion on therapy outcomes and determine whether fusion ability is advantageous for hunter virus design, we have constructed a model to account for the possibility of hunter-HIV fusion. The study was based on a target cell-limited model of HIV infection and it examined the hunter therapeutic effect on recovering the HIV main target cells, the activated CD4+ T lymphocytes. These cells assist in setting up an immune response to opportunistic infections. The study analyzed the hunter dual mechanisms to control infection and because of diverse estimates for viral production and clearance of HIV, simulations were examined at rates spanning an order of magnitude. Results indicate that without hunter-HIV fusion ability, hunters that kill HIV-infected cells lead to a substantial recovery of healthy cell population at both low and high HIV turnover rates. When hunter-HIV fusion is included, cell recovery was particularly enhanced at lower HIV turnover rates. This study shows that the fusion ability, in addition to hunter infection ability, could be a favorable attribute for improving the efficacy of hunter-viral therapy. These results provide support for the potential use of engineered viruses to control HIV and other viral infections.

  9. Valutazione di un test per la determinazione simultanea degli anticorpi e antigene p24 dell’HIV

    Directory of Open Access Journals (Sweden)

    Nadia Zanchetta

    2006-03-01

    Full Text Available A fourth generation immunoassay for the detection of antibodies to HIV-1 and HIV-2 and of HIV antigen p24 (Abbott Architect HIV Ag/Ab Combo has been evaluated in comparison with two Ab-only third generation assays on 894 routine specimens and on preselected repository specimens.The Combo assay showed a better specificity (99.88% vs. 99.43-99.83% and an analytical sensitivity for p24 of 22 pg/mL on a BBI commercial panel. The Architect assays gave a negative result on 22/24 repository false positive specimens from 18 subjects and, conversely, was positive on all the 39 repository specimens from 24 HIV-positive patients. On six patients with acute HIV infection the Architect assay gave an earlier positivity than the antibody-only assays (EIA and WB on three cases, all viremic and positive for HIV p24.The performance characteristics of the new HIV Combo assay guarantee an advanced clinical sensitivity and a high specificity.

  10. Genetic and antigenic characterisation of serotype A FMD viruses from East Africa to select new vaccine strains.

    Science.gov (United States)

    Bari, Fufa D; Parida, Satya; Tekleghiorghis, Tesfaalem; Dekker, Aldo; Sangula, Abraham; Reeve, Richard; Haydon, Daniel T; Paton, David J; Mahapatra, Mana

    2014-10-07

    Vaccine strain selection for emerging foot-and-mouth disease virus (FMDV) outbreaks in enzootic countries can be addressed through antigenic and genetic characterisation of recently circulating viruses. A total of 56 serotype A FMDVs isolated between 1998 and 2012, from Central, East and North African countries were characterised antigenically by virus neutralisation test using antisera to three existing and four candidate vaccine strains and, genetically by characterising the full capsid sequence data. A Bayesian analysis of the capsid sequence data revealed the viruses to be of either African or Asian topotypes with subdivision of the African topotype viruses into four genotypes (Genotypes I, II, IV and VII). The existing vaccine strains were found to be least cross-reactive (good matches observed for only 5.4-46.4% of the sampled viruses). Three bovine antisera, raised against A-EA-2007, A-EA-1981 and A-EA-1984 viruses, exhibited broad cross-neutralisation, towards more than 85% of the circulating viruses. Of the three vaccines, A-EA-2007 was the best showing more than 90% in-vitro cross-protection, as well as being the most recent amongst the vaccine strains used in this study. It therefore appears antigenically suitable as a vaccine strain to be used in the region in FMD control programmes. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. Production of Japanese Encephalitis Virus Antigens in Plants Using Bamboo Mosaic Virus-Based Vector

    Directory of Open Access Journals (Sweden)

    Tsung-Hsien Chen

    2017-05-01

    Full Text Available Japanese encephalitis virus (JEV is among the major threats to public health in Asia. For disease control and prevention, the efficient production of safe and effective vaccines against JEV is in urgent need. In this study, we produced a plant-made JEV vaccine candidate using a chimeric virus particle (CVP strategy based on bamboo mosaic virus (BaMV for epitope presentation. The chimeric virus, designated BJ2A, was constructed by fusing JEV envelope protein domain III (EDIII at the N-terminus of BaMV coat protein, with an insertion of the foot-and-mouth disease virus 2A peptide to facilitate the production of both unfused and epitope-presenting for efficient assembly of the CVP vaccine candidate. The strategy allowed stable maintenance of the fusion construct over long-term serial passages in plants. Immuno-electron microscopy examination and immunization assays revealed that BJ2A is able to present the EDIII epitope on the surface of the CVPs, which stimulated effective neutralizing antibodies against JEV infection in mice. This study demonstrates the efficient production of an effective CVP vaccine candidate against JEV in plants by the BaMV-based epitope presentation system.

  12. Production of Japanese Encephalitis Virus Antigens in Plants Using Bamboo Mosaic Virus-Based Vector.

    Science.gov (United States)

    Chen, Tsung-Hsien; Hu, Chung-Chi; Liao, Jia-Teh; Lee, Yi-Ling; Huang, Ying-Wen; Lin, Na-Sheng; Lin, Yi-Ling; Hsu, Yau-Heiu

    2017-01-01

    Japanese encephalitis virus (JEV) is among the major threats to public health in Asia. For disease control and prevention, the efficient production of safe and effective vaccines against JEV is in urgent need. In this study, we produced a plant-made JEV vaccine candidate using a chimeric virus particle (CVP) strategy based on bamboo mosaic virus (BaMV) for epitope presentation. The chimeric virus, designated BJ2A, was constructed by fusing JEV envelope protein domain III (EDIII) at the N-terminus of BaMV coat protein, with an insertion of the foot-and-mouth disease virus 2A peptide to facilitate the production of both unfused and epitope-presenting for efficient assembly of the CVP vaccine candidate. The strategy allowed stable maintenance of the fusion construct over long-term serial passages in plants. Immuno-electron microscopy examination and immunization assays revealed that BJ2A is able to present the EDIII epitope on the surface of the CVPs, which stimulated effective neutralizing antibodies against JEV infection in mice. This study demonstrates the efficient production of an effective CVP vaccine candidate against JEV in plants by the BaMV-based epitope presentation system.

  13. CD127 expression, exhaustion status and antigen specific proliferation predict sustained virologic response to IFN in HCV/HIV co-infected individuals.

    Directory of Open Access Journals (Sweden)

    Hassen Kared

    Full Text Available Hepatitis C virus (HCV infection is a major cause of morbidity and mortality in the HIV co-infected population. Interferon-alpha (IFN-α remains a major component of anti-HCV therapy despite its deleterious effects on the immune system. Furthermore, IFN-α was recently shown to diminish the size of the latent HIV reservoir. The objectives of this study were to monitor the impact of IFN-α on T cell phenotype and proliferation of HIV and HCV-specific T cells during IFN therapy, and to identify immune markers that can predict the response to IFN in HICV/HIV co-infected patients. We performed longitudinal analyses of T cell numbers, phenotype and function in co-infected patients undergoing IFN-α therapy with different outcomes including IFN-α non-responders (NR (n = 9 and patients who achieved sustained virologic response (SVR (n = 19. We examined the expression of activation (CD38, HLA-DR, functional (CD127 and exhaustion markers (PD1, Tim-3, CD160 and CD244 on total CD4 and CD8 T cells before, during and after therapy. In addition, we examined the HIV- and HCV-specific proliferative responses against HIV-p24 and HCV-NS3 proteins. Frequencies of CD127+ CD4 T cells were higher in SVR than in NR patients at baseline. An increase in CD127 expression on CD8 T cells was observed after IFN-α therapy in all patients. In addition, CD8 T cells from NR patients expressed a higher exhaustion status at baseline. Finally, SVR patients exhibited higher proliferative response against both HIV and HCV antigens at baseline. Altogether, SVR correlated with higher expression of CD127, lower T cell exhaustion status and better HIV and HCV proliferative responses at baseline. Such factors might be used as non-invasive methods to predict the success of IFN-based therapies in co-infected individuals.

  14. Immunogenic profiling in mice of a HIV/AIDS vaccine candidate (MVA-B expressing four HIV-1 antigens and potentiation by specific gene deletions.

    Directory of Open Access Journals (Sweden)

    Juan García-Arriaza

    Full Text Available BACKGROUND: The immune parameters of HIV/AIDS vaccine candidates that might be relevant in protection against HIV-1 infection are still undefined. The highly attenuated poxvirus strain MVA is one of the most promising vectors to be use as HIV-1 vaccine. We have previously described a recombinant MVA expressing HIV-1 Env, Gag, Pol and Nef antigens from clade B (referred as MVA-B, that induced HIV-1-specific immune responses in different animal models and gene signatures in human dendritic cells (DCs with immunoregulatory function. METHODOLOGY/PRINCIPAL FINDINGS: In an effort to characterize in more detail the immunogenic profile of MVA-B and to improve its immunogenicity we have generated a new vector lacking two genes (A41L and B16R, known to counteract host immune responses by blocking the action of CC-chemokines and of interleukin 1beta, respectively (referred as MVA-B DeltaA41L/DeltaB16R. A DNA prime/MVA boost immunization protocol was used to compare the adaptive and memory HIV-1 specific immune responses induced in mice by the parental MVA-B and by the double deletion mutant MVA-B DeltaA41L/DeltaB16R. Flow cytometry analysis revealed that both vectors triggered HIV-1-specific CD4(+ and CD8(+ T cells, with the CD8(+ T-cell compartment responsible for >91.9% of the total HIV-1 responses in both immunization groups. However, MVA-B DeltaA41L/DeltaB16R enhanced the magnitude and polyfunctionality of the HIV-1-specific CD4(+ and CD8(+ T-cell immune responses. HIV-1-specific CD4(+ T-cell responses were polyfunctional and preferentially Env-specific in both immunization groups. Significantly, while MVA-B induced preferentially Env-specific CD8(+ T-cell responses, MVA-B DeltaA41L/DeltaB16R induced more GPN-specific CD8(+ T-cell responses, with an enhanced polyfunctional pattern. Both vectors were capable of producing similar levels of antibodies against Env. CONCLUSIONS/SIGNIFICANCE: These findings revealed that MVA-B and MVA-B DeltaA41L/DeltaB16R

  15. Performance characteristics of serologic tests for human immunodeficiency virus type 1 (HIV-1) antibody among Minnesota blood donors. Public health and clinical implications.

    Science.gov (United States)

    MacDonald, K L; Jackson, J B; Bowman, R J; Polesky, H F; Rhame, F S; Balfour, H H; Osterholm, M T

    1989-04-15

    To evaluate performance characteristics of sequential enzyme immunoassay (EIA) and Western blot human immunodeficiency virus type 1 (HIV-1) antibody testing in a low-risk population. Three-year prospective study of a selected sample from a community-based population. Two blood collection facilities in Minnesota. Minnesota blood donors. During the study period, 630,190 units of blood (donations) from an estimated 290,110 Minnesota-resident donors were screened for HIV-1 antibody. Seventeen Minnesota-resident donors were identified as positive for HIV-1 antibody. Sixteen donors were available for follow-up HIV-1 culture: all were culture positive. The other donor, who was not available for follow-up culture, was likely infected with HIV-1 based on a history of high-risk behavior and positive serologic findings for hepatitis B surface antigen. Using 95% binomial confidence intervals, performance characteristics for sequential EIA and Western blot HIV-1 antibody serology were as follows: false-positive rate by number of donations, 0% to 0.0006%; specificity by number of donations, 99.9994% to 100%; predictive value of a positive test, 81% to 100%. In this low-risk population, the false-positive rate of serologic tests for HIV-1 antibody, using HIV-1 culture as the definitive standard for infection status, was extremely low and test specificity was extremely high.

  16. Prevalence of HIV infection in seronegative high-risk individuals examined by virus isolation and PCR

    DEFF Research Database (Denmark)

    Nielsen, C; Teglbjærg, Lars Stubbe; Pedersen, C

    1991-01-01

    HIV seronegative individuals with high-risk behavior were tested for HIV infection by sensitive virus isolation techniques using T4 lymphocytes and monocyte/macrophages, and by detection of proviral DNA using PCR with three different sets of nested primers. No evidence of HIV infection was found...... among the 31 seronegative high-risk subjects, either by virus isolation of by PCR (97.5% confidence limits, 0-11). Our results indicate that ongoing HIV infection in seronegative persons at high risk of infection is a rare event....

  17. Exercise and Human Immunodeficiency Virus (HIV-1) Infection

    Science.gov (United States)

    Lawless, DeSales; Jackson, Catherine G. R.; Greenleaf, John E.

    1995-01-01

    The human immune system is highly efficient and remarkably protective when functioning properly. Similar to other physiological systems, it functions best when the body is maintained with a balanced diet, sufficient rest and a moderately stress-free lifestyle. It can be disrupted by inappropriate drug use and extreme emotion or exertion. The functioning of normal or compromised immune systems can be enhanced by properly prescribed moderate exercise conditioning regimens in healthy people, and in some human immunodeficiency virus (HIV-1)-infected patients but not in others who unable to complete an interval training program. Regular exercise conditioning in healthy people reduces cardiovascular risk factors, increases stamina, facilitates bodyweight control, and reduces stress by engendering positive feelings of well-being. Certain types of cancer may also be suppressed by appropriate exercise conditioning. Various exercise regimens are being evaluated as adjunct treatments for medicated patients with the HIV-1 syndrome. Limited anecdotal evidence from patients suggests that moderate exercise conditioning is per se responsible for their survival well beyond expectancy. HIV-1-infected patients respond positively, both physiologically and psychologically, to moderate exercise conditioning. However, the effectiveness of any exercise treatment programme depends on its mode, frequency, intensity and duration when prescribed o complement the pathological condition of the patient. The effectiveness of exercise conditioning regimens in patients with HIV-1 infection is reviewed in this article. In addition, we discuss mechanisms and pathways, involving the interplay of psychological and physiological factors, through which the suppressed immune system can be enhanced. The immune modulators discussed are endogenous opioids, cytokines, neurotransmitters and other hormones. Exercise conditioning treatment appears to be more effective when combined with other stress management

  18. Comparable Antigenicity and Immunogenicity of Oligomeric Forms of a Novel, Acute HIV-1 Subtype C gp145 Envelope for Use in Preclinical and Clinical Vaccine Research.

    Science.gov (United States)

    Wieczorek, Lindsay; Krebs, Shelly J; Kalyanaraman, Vaniambadi; Whitney, Stephen; Tovanabutra, Sodsai; Moscoso, Carlos G; Sanders-Buell, Eric; Williams, Constance; Slike, Bonnie; Molnar, Sebastian; Dussupt, Vincent; Alam, S Munir; Chenine, Agnes-Laurence; Tong, Tina; Hill, Edgar L; Liao, Hua-Xin; Hoelscher, Michael; Maboko, Leonard; Zolla-Pazner, Susan; Haynes, Barton F; Pensiero, Michael; McCutchan, Francine; Malek-Salehi, Shawyon; Cheng, R Holland; Robb, Merlin L; VanCott, Thomas; Michael, Nelson L; Marovich, Mary A; Alving, Carl R; Matyas, Gary R; Rao, Mangala; Polonis, Victoria R

    2015-08-01

    Eliciting broadly reactive functional antibodies remains a challenge in human immunodeficiency virus type 1 (HIV-1) vaccine development that is complicated by variations in envelope (Env) subtype and structure. The majority of new global HIV-1 infections are subtype C, and novel antigenic properties have been described for subtype C Env proteins. Thus, an HIV-1 subtype C Env protein (CO6980v0c22) from an infected person in the acute phase (Fiebig stage I/II) was developed as a research reagent and candidate immunogen. The gp145 envelope is a novel immunogen with a fully intact membrane-proximal external region (MPER), extended by a polylysine tail. Soluble gp145 was enriched for trimers that yielded the expected "fan blade" motifs when visualized by cryoelectron microscopy. CO6980v0c22 gp145 reacts with the 4E10, PG9, PG16, and VRC01 HIV-1 neutralizing monoclonal antibodies (MAbs), as well as the V1/V2-specific PGT121, 697, 2158, and 2297 MAbs. Different gp145 oligomers were tested for immunogenicity in rabbits, and purified dimers, trimers, and larger multimers elicited similar levels of cross-subtype binding and neutralizing antibodies to tier 1 and some tier 2 viruses. Immunized rabbit sera did not neutralize the highly resistant CO6980v0c22 pseudovirus but did inhibit the homologous infectious molecular clone in a peripheral blood mononuclear cell (PBMC) assay. This Env is currently in good manufacturing practice (GMP) production to be made available for use as a clinical research tool and further evaluation as a candidate vaccine. At present, the product pipeline for HIV vaccines is insufficient and is limited by inadequate capacity to produce large quantities of vaccine to standards required for human clinical trials. Such products are required to evaluate critical questions of vaccine formulation, route, dosing, and schedule, as well as to establish vaccine efficacy. The gp145 Env protein presented in this study forms physical trimers, binds to many of the

  19. Persistence of hepatitis C virus in a white population: associations with human leukocyte antigen class 1.

    LENUS (Irish Health Repository)

    Fanning, Liam J

    2012-02-03

    The aim of this study was to define novel associations between human leukocyte antigen (HLA) class 1 alleles and persistence or clearance of the hepatitis C virus (HCV) in a white population. All individuals in the study were seropositive for anti-HCV antibodies. Viral status was determined by the Roche HCV Amplicor test. HLA-A, -B, -C allelic group profile was molecularly defined by reverse line probe hybridization. The strongest individual allelic group associations with persistent HCV infection were HLA A*11 (p = 0.044) and Cw*04 (p = 0.006). However, only the HLA C*04 association survived correction for multiple comparisons. Further analysis of alleles in linkage with HLA Cw*04 revealed that the haplotype HLA A*11, Cw*04 was present in 11 individuals, 10 of whom were viremic (p = 0.05). No gene dosage effect was observed. No association between HLA class 1 allelic groups and aviremia and virus load was evident in this white population. HLA B*44 is associated with low virus load in human immunodeficiency virus disease, but this association was not evident in this HCV-infected population. Novel HLA class 1 alleles associated with persistence of HCV have been identified.

  20. Recombinant Jembrana disease virus proteins as antigens for the detection of antibody to bovine lentiviruses.

    Science.gov (United States)

    Burkala, E J; Narayani, I; Hartaningsih, N; Kertayadnya, G; Berryman, D I; Wilcox, G E

    1998-09-01

    Jembrana disease virus (JDV) is a recently identified bovine lentivirus causing an acute severe disease syndrome in banteng cattle (Bos javanicus) and a milder disease syndrome in Bos taurus cattle in Indonesia. The virus is closely related genetically to the previously identified bovine lentivirus, bovine immunodeficiency virus (BIV). Recombinant clones were produced which contained the capsid (CA) and transmembrane (TM) subunits of the respective gag and env open reading frames of JDV. The proteins were expressed as fusions to the glutathione-s-transferase (GST) enzyme in Escherichia coli and purification was achieved using affinity chromatography via immobilized reduced glutathione. The soluble recombinant CA and TM antigens of JDV were reacted in western immunoblots with both serum antibodies from JDV-infected Bos javanicus cattle and Bos taurus cattle immunized with BIV. The recombinant CA protein of JDV reacted equally well with both the JDV and BIV antisera. The recombinant TM protein of JDV also reacted with antibody from the JDV infected cattle and with the BIV antisera. The results indicated conservation of immunogenic epitopes of the CA and TM proteins of the two viruses. The production of the recombinant proteins should enable the development of rapid and sensitive serological tests for JDV and BIV, and tools for further study of the immune response to JDV and the differential epidemiology of JDV infections in cattle.

  1. Hepatitis B virus sequencing and liver fibrosis evaluation in HIV/HBV co-infected Nigerians.

    Science.gov (United States)

    Grant, Jennifer; Agbaji, Oche; Kramvis, Anna; Yousif, Mukhlid; Auwal, Mu'azu; Penugonda, Sudhir; Ugoagwu, Placid; Murphy, Robert; Hawkins, Claudia

    2017-06-01

    Molecular characteristics of hepatitis B virus (HBV), such as genotype and genomic mutations, may contribute to liver-related morbidity and mortality. The association of these characteristics with liver fibrosis severity in sub-Saharan Africa is uncertain. We aimed to characterise molecular HBV features in human immunodeficiency virus (HIV)/HBV co-infected Nigerians and evaluate associations between these characteristics and liver fibrosis severity before and after antiretroviral therapy (ART) initiation. HIV/HBV co-infected Nigerians underwent liver fibrosis estimation by transient elastography (TE) prior to and 36 months after ART initiation. Basal core promoter/precore (BCP/PC) and preS1/preS2/S regions of HBV were sequenced from baseline plasma samples. We evaluated associations between HBV mutations and liver fibrosis severity by univariate and multivariable regression. At baseline, 94 patients underwent TE with median liver stiffness of 6.4 (IQR 4.7-8.7) kPa. Patients were predominantly infected with HBV genotype E (45/46) and HBe-antigen negative (75/94, 79.8%). We identified BCP A1762T/G1764A in 15/35 (43%), PC G1896A in 20/35 (57%), 'a' determinant mutations in 12/45 (26.7%) and preS2 deletions in 6/16 (37.5%). PreS2 mutations were associated with advanced fibrosis in multivariable analysis. At follow-up, median liver stiffness was 5.2 (IQR 4.1-6.6) kPa. No HBV molecular characteristics were associated with lack of fibrosis regression, although HIV virologic control, body mass index (BMI) and baseline CD4+ T-cell count were associated with a decline in fibrosis stage. Frequent BCP/PC and preS1/preS2/S mutations were found in ART-naïve HIV/HBV co-infected Nigerians. Median liver stiffness declined after initiation of ART, regardless of pre-ART HBV mutational pattern or virologic characteristics. © 2017 John Wiley & Sons Ltd.

  2. GB virus C infection is associated with a reduced rate of reactivation of latent HIV and protection against activation-induced T-cell death

    Science.gov (United States)

    Rydze, Robert T; Bhattarai, Nirjal; Stapleton, Jack T

    2013-01-01

    Background GB virus C (GBV-C) coinfection is associated with reduced immune activation and a block in CD4+ T-cell proliferation following interleukin-2 (IL-2) therapy in HIV-infected individuals. We examined peripheral blood mononuclear cells (PBMCs) from HIV-infected subjects with and without GBV-C viraemia to determine if GBV-C correlated with reactivation of latent HIV, T-cell proliferation or T-cell survival following in vitro activation with phytohaemagglutinin A and IL-2 (PHA/IL-2). Methods HIV-infected subjects whose HIV viral load was suppressed on combination antiretroviral therapy (cART) for >6 months were studied. PBMCs were cultured with and without PHA/IL-2 and monitored for HIV reactivation, proliferation and survival. GBV-C viraemia and in vitro replication were detected by real-time RT-PCR. HIV reactivation was determined by measuring HIV p24 antigen in culture supernatants. Proliferation was measured by counting viable cells and survival measured by flow cytometry. Results Of 49 HIV-infected individuals, 26 had GBV-C viraemia. Significantly less HIV reactivation and PBMC proliferation following in vitro activation with PHA/IL-2 was observed in samples from GBV-C viraemic subjects compared with non-viraemic controls. Following 5 weeks in culture, GBV-C replication was associated with preservation of CD4+ and CD8+ T-cells compared with non-viraemic controls. Conclusions GBV-C appears to inhibit immune activation and IL-2 signalling pathways, which might contribute to a reduction in reactivation of latent HIV from cellular reservoirs. In addition, GBV-C viraemia was associated with a reduction in activation-induced T-cell death. GBV-C-associated T-cell effects could contribute to the observed protective effect of GBV-C coinfection in HIV-infected individuals. PMID:22951385

  3. Identification of Low- and High-Impact Hemagglutinin Amino Acid Substitutions That Drive Antigenic Drift of Influenza A(H1N1 Viruses.

    Directory of Open Access Journals (Sweden)

    William T Harvey

    2016-04-01

    Full Text Available Determining phenotype from genetic data is a fundamental challenge. Identification of emerging antigenic variants among circulating influenza viruses is critical to the vaccine virus selection process, with vaccine effectiveness maximized when constituents are antigenically similar to circulating viruses. Hemagglutination inhibition (HI assay data are commonly used to assess influenza antigenicity. Here, sequence and 3-D structural information of hemagglutinin (HA glycoproteins were analyzed together with corresponding HI assay data for former seasonal influenza A(H1N1 virus isolates (1997-2009 and reference viruses. The models developed identify and quantify the impact of eighteen amino acid substitutions on the antigenicity of HA, two of which were responsible for major transitions in antigenic phenotype. We used reverse genetics to demonstrate the causal effect on antigenicity for a subset of these substitutions. Information on the impact of substitutions allowed us to predict antigenic phenotypes of emerging viruses directly from HA gene sequence data and accuracy was doubled by including all substitutions causing antigenic changes over a model incorporating only the substitutions with the largest impact. The ability to quantify the phenotypic impact of specific amino acid substitutions should help refine emerging techniques that predict the evolution of virus populations from one year to the next, leading to stronger theoretical foundations for selection of candidate vaccine viruses. These techniques have great potential to be extended to other antigenically variable pathogens.

  4. Potential for insect transmission of HIV: experimental exposure of Cimex hemipterus and Toxorhynchites amboinensis to human immunodeficiency virus.

    Science.gov (United States)

    Webb, P A; Happ, C M; Maupin, G O; Johnson, B J; Ou, C Y; Monath, T P

    1989-12-01

    Human immunodeficiency virus (HIV) was detected in bedbugs (Cimex hemipterus) up to 8 d after oral exposure to highly concentrated virus in blood meals, but no virus replication was observed. HIV did not replicate in either intraabdominally inoculated bedbugs or intrathoracically inoculated mosquitoes (Toxorhynchites amboinensis). The virus was not detected in bedbug feces. Mechanical transmission of HIV by bedbugs could not be demonstrated in an in vitro model. The persistence of HIV in an insect or on its mouthparts is one of many factors necessary for mechanical transmission in nature. The risk of insect transmission of HIV appears to be extremely low or nonexistent.

  5. Chimeric antigen receptor (CAR)-modified natural killer cell-based immunotherapy and immunological synapse formation in cancer and HIV.

    Science.gov (United States)

    Liu, Dongfang; Tian, Shuo; Zhang, Kai; Xiong, Wei; Lubaki, Ndongala Michel; Chen, Zhiying; Han, Weidong

    2017-12-01

    Cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells contribute to the body's immune defenses. Current chimeric antigen receptor (CAR)-modified T cell immunotherapy shows strong promise for treating various cancers and infectious diseases. Although CAR-modified NK cell immunotherapy is rapidly gaining attention, its clinical applications are mainly focused on preclinical investigations using the NK92 cell line. Despite recent advances in CAR-modified T cell immunotherapy, cost and severe toxicity have hindered its widespread use. To alleviate these disadvantages of CAR-modified T cell immunotherapy, additional cytotoxic cell-mediated immunotherapies are urgently needed. The unique biology of NK cells allows them to serve as a safe, effective, alternative immunotherapeutic strategy to CAR-modified T cells in the clinic. While the fundamental mechanisms underlying the cytotoxicity and side effects of CAR-modified T and NK cell immunotherapies remain poorly understood, the formation of the immunological synapse (IS) between CAR-modified T or NK cells and their susceptible target cells is known to be essential. The role of the IS in CAR T and NK cell immunotherapies will allow scientists to harness the power of CAR-modified T and NK cells to treat cancer and infectious diseases. In this review, we highlight the potential applications of CAR-modified NK cells to treat cancer and human immunodeficiency virus (HIV), and discuss the challenges and possible future directions of CAR-modified NK cell immunotherapy, as well as the importance of understanding the molecular mechanisms of CAR-modified T cell- or NK cell-mediated cytotoxicity and side effects, with a focus on the CAR-modified NK cell IS.

  6. Effect of HIV-1 envelope cytoplasmic tail on adenovirus primed virus encoded virus-like particle immunizations

    DEFF Research Database (Denmark)

    Andersson, Anne Marie C; Ragonnaud, Emeline; Seaton, Kelly E.

    2016-01-01

    The low number of envelope (Env) spikes presented on native HIV-1 particles is a major impediment for HIV-1 prophylactic vaccine development. We designed virus-like particle encoding adenoviral vectors utilizing SIVmac239 Gag as an anchor for full length and truncated HIV-1 M consensus Env...... were found between the different priming regimens as both induced high titered tier 1 neutralizing antibodies, but no tier 2 antibodies, possibly reflecting the similar presentation of trimer specific antibody epitopes. The described vaccine regimens provide insight into the effects of the HIV-1 Env...

  7. Cultivation of attenuated hepatitis A virus antigen in a titanium static mixer reactor.

    Science.gov (United States)

    Junker, B H; Seamans, T C; Ramasubramanyan, K; Aunins, J; Paul, E; Buckland, B C

    1994-12-01

    The titanium static mixer reactor, demonstrated for a variety of vaccine processes during the late 197s, was investigated for the production of attenuated hepatitis A virus antigen from anchorage-dependent MRC-5 cells. This reactor system used Charles River Biotechnological Services cabinets for monitoring and process control. Cell inoculation protocols, using 6000-10,000 cells/cm(2), resulted on over 95% attachment at both the laboratory and pilot scales. Indirect monitoring techniques using oxygen, glucose, L-serine, and L-glutamine uptake rates were indicative of cell growth prior to virus inoculation as well as environmental and/or nutrient limitations. Seven laboratory-scale (3900 cm(2)) runs and one pilotscale (265,000 cm(2)) run were conducted to investigate refeeding regiments, parallel versus perpendicular element orientation, increased element surface area per unit volume, and scale-up performance. In general, lysate antigen yields achieved were similar to those of parallel T-flasks cultivated under similar conditions.

  8. First report of Bovine Viral Diarrhea Virus antigen from pneumonic cattle in Sudan

    Directory of Open Access Journals (Sweden)

    Intisar Kamil Saeed

    2015-06-01

    Full Text Available To explore the expected role of Bovine Viral Diarrhea Virus (BVDV in pneumonia in cattle, cattle lungs (n=242 showing signs of pneumonia were collected from slaughter houses of three different localities located at Northern, Central and Western Sudan during 2010–2013. The collected samples were tested for the presence of BVDV antigen using Enzyme-Linked Immunosorbent Assay (ELISA, and Fluorescent Antibody Test (FAT. Twenty six (10.7% out of 242 samples were found to be positive for BVDV. Positive results were seen in all the three studied areas, with the highest prevalence (16.7%; n=4/24 at Gezira State in Central Sudan. BVDV genome could be detected in all ELISA positive samples. The results indicated the existence of BVDV infection in cattle in different areas in Sudan, and its possible association with respiratory infections in cattle. Analysis using BLAST indicated that the sequence was identical to the previously reported BVDV-1 (GenBank accession AF220247.1.; nucleotide A was found in our study at position 9 of our sequence, whereas T was present instead in the reference virus. This is the first report of detecting BVDV antigen, genome, and its sequence analysis collected from cattle lungs in Sudan.

  9. Recombinant rabies virus particles presenting botulinum neurotoxin antigens elicit a protective humoral response in vivo

    Directory of Open Access Journals (Sweden)

    Andrew W Hudacek

    2014-01-01

    Full Text Available Botulinum neurotoxins are one of the most potent toxins found in nature, with broad medical applications from cosmetics to the treatment of various neuropathies. Additionally, these toxins are classified as Category A-Tier 1 agents, with human lethal doses calculated at as little as 90 ng depending upon the route of administration. Of the eight distinct botulinum neurotoxin serotypes, the most common causes of human illness are from serotypes /A, /B, and /E. Protection can be achieved by eliciting antibody responses against the receptor-binding domain of the neurotoxin. Our previous research has shown that recombinant rabies virus–based particles can effectively present heterologous antigens. Here, we describe a novel strategy using recombinant rabies virus particles that elicits a durable humoral immune response against the botulinum neurotoxin receptor binding domains from serotypes /A, /B, and /E. Following intramuscular administration of β-propiolactone-inactivated rabies virus particles, mice elicited specific immune responses against the cognate antigen. Administration of a combination of these vectors also demonstrated antibody responses against all three serotypes based on enzyme-linked immunosorbent assay (ELISA measurements, with minimal decay within the study timeline. Complete protection was achieved against toxin challenge from the serotypes /A and /B and partial protection for /E, indicating that a multivalent approach is feasible.

  10. H1N1 influenza vaccination in HIV-infected women on effective antiretroviral treatment did not induce measurable antigen-driven proliferation of the HIV-1 proviral reservoir.

    Science.gov (United States)

    Wagner, Thor A; Huang, Hannah C; Salyer, Christen E; Richardson, Kelly M; Weinberg, Adriana; Nachman, Sharon; Frenkel, Lisa M

    2017-02-13

    Antigen-induced activation and proliferation of HIV-1-infected cells is hypothesized to be a mechanism of HIV persistence during antiretroviral therapy. The objective of this study was to determine if proliferation of H1N1-specific HIV-infected cells could be detected following H1N1 vaccination. This study utilized cryopreserved PBMC from a previously conducted trial of H1N1 vaccination in HIV-infected pregnant women. HIV-1 DNA concentrations and 437 HIV-1 C2V5 env DNA sequences were analyzed from ten pregnant women on effective antiretroviral therapy, before and 21 days after H1N1 influenza vaccination. HIV-1 DNA concentration did not change after vaccination (median pre- vs. post-vaccination: 95.77 vs. 41.28 copies/million PBMC, p = .37). Analyses of sequences did not detect evidence of HIV replication or proliferation of infected cells. Antigenic stimulation during effective ART did not have a detectable effect on the genetic makeup of the HIV-1 DNA reservoir. Longitudinal comparison of the amount and integration sites of HIV-1 in antigen-specific cells to chronic infections (such as herpesviruses) may be needed to definitively evaluate whether antigenic stimulation induces proliferation of HIV-1 infected cells.

  11. Impaired Cytokine Responses to Epstein-Barr Virus Antigens in Systemic Lupus Erythematosus Patients

    Directory of Open Access Journals (Sweden)

    Anette Holck Draborg

    2016-01-01

    Full Text Available We analyzed cytokine responses against latent and lytic Epstein-Barr virus (EBV antigens in systemic lupus erythematosus (SLE patients and healthy controls (HCs to obtain an overview of the distinctive immune regulatory response in SLE patients and to expand the previously determined impaired EBV-directed T-cell response. The concentrations of 14 cytokines (IL2, IL4, IL5, IL6, IL10, IL12, IL17, IL18, IL1β, IFNγ, TNFα, TNFβ, TGFβ, and GM-CSF were quantified upon stimulation of whole blood with latent state antigen EBNA1, lytic cycle antigen EBV-EA/D, and the superantigen SEB. To avoid results affected by lack of lymphocytes, we focused on SLE patients with normal levels. Decreased induction of IL12, IFNγ, IL17, and IL6 upon EBNA1 stimulation and that of IFNγ, IL6, TNFβ, IL1β, and GM-CSF upon EBV-EA/D stimulation were detected in SLE patients compared to HCs. IFNγ responses, especially, were shown to be reduced. Induction of several cytokines was furthermore impaired in SLE patients upon SEB stimulation, but no difference was observed in basic levels. Results substantiate the previously proposed impaired regulation of the immune response against latent and lytic cycle EBV infection in SLE patients without lymphopenia. Furthermore, results indicate general dysfunction of leukocytes and their cytokine regulations in SLE patients.

  12. Impaired Cytokine Responses to Epstein-Barr Virus Antigens in Systemic Lupus Erythematosus Patients.

    Science.gov (United States)

    Draborg, Anette Holck; Sandhu, Noreen; Larsen, Nanna; Lisander Larsen, Janni; Jacobsen, Søren; Houen, Gunnar

    2016-01-01

    We analyzed cytokine responses against latent and lytic Epstein-Barr virus (EBV) antigens in systemic lupus erythematosus (SLE) patients and healthy controls (HCs) to obtain an overview of the distinctive immune regulatory response in SLE patients and to expand the previously determined impaired EBV-directed T-cell response. The concentrations of 14 cytokines (IL2, IL4, IL5, IL6, IL10, IL12, IL17, IL18, IL1β, IFNγ, TNFα, TNFβ, TGFβ, and GM-CSF) were quantified upon stimulation of whole blood with latent state antigen EBNA1, lytic cycle antigen EBV-EA/D, and the superantigen SEB. To avoid results affected by lack of lymphocytes, we focused on SLE patients with normal levels. Decreased induction of IL12, IFNγ, IL17, and IL6 upon EBNA1 stimulation and that of IFNγ, IL6, TNFβ, IL1β, and GM-CSF upon EBV-EA/D stimulation were detected in SLE patients compared to HCs. IFNγ responses, especially, were shown to be reduced. Induction of several cytokines was furthermore impaired in SLE patients upon SEB stimulation, but no difference was observed in basic levels. Results substantiate the previously proposed impaired regulation of the immune response against latent and lytic cycle EBV infection in SLE patients without lymphopenia. Furthermore, results indicate general dysfunction of leukocytes and their cytokine regulations in SLE patients.

  13. Defining influenza A virus hemagglutinin antigenic drift by sequential monoclonal antibody selection.

    Science.gov (United States)

    Das, Suman R; Hensley, Scott E; Ince, William L; Brooke, Christopher B; Subba, Anju; Delboy, Mark G; Russ, Gustav; Gibbs, James S; Bennink, Jack R; Yewdell, Jonathan W

    2013-03-13

    Human influenza A virus (IAV) vaccination is limited by "antigenic drift," rapid antibody-driven escape reflecting amino acid substitutions in the globular domain of hemagglutinin (HA), the viral attachment protein. To better understand drift, we used anti-hemagglutinin monoclonal Abs (mAbs) to sequentially select IAV escape mutants. Twelve selection steps, each resulting in a single amino acid substitution in the hemagglutinin globular domain, were required to eliminate antigenicity defined by monoclonal or polyclonal Abs. Sequential mutants grow robustly, showing the structural plasticity of HA, although several hemagglutinin substitutions required an epistatic substitution in the neuraminidase glycoprotein to maximize growth. Selecting escape mutants from parental versus sequential variants with the same mAb revealed distinct escape repertoires, attributed to contextual changes in antigenicity and the mutation landscape. Since each hemagglutinin mutation potentially sculpts future mutation space, drift can follow many stochastic paths, undermining its unpredictability and underscoring the need for drift-insensitive vaccines. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. T-cell subset alterations and lymphocyte responsiveness to mitogens and antigen during severe primary infection with HIV: a case series of seven consecutive HIV seroconverters

    DEFF Research Database (Denmark)

    Pedersen, C; Dickmeiss, E; Gaub, J

    1990-01-01

    Seven consecutive patients who presented with a severe acute mononucleosis-like illness associated with HIV seroconversion were evaluated by T-cell subset enumerations and measurements of lymphocyte transformation responses to mitogens and antigen during both their primary illness and a 1-year...... of a relatively low number of CD4 lymphocytes. Primary infection was followed by prolonged and severe cellular hyporesponsiveness to both mitogens and antigen. At the last follow-up, responses to pokeweed mitogen were still severely impaired, with a median 19% (range 7-50%) of that observed in healthy controls...

  15. Identification of immediate early gene products of bovine herpes virus 1 (BHV-1) as dominant antigens recognized by CD8 T cells in immune cattle

    DEFF Research Database (Denmark)

    Hart, Jane; MacHugh, Niall D.; Sheldrake, Tara

    2017-01-01

    In common with other herpes viruses, bovine herpes virus 1 (BHV-1) induces strong virus-specific CD8 T-cell responses. However, there is a paucity of information on the antigenic specificity of the responding T-cells. The development of a system to generate virus-specific CD8 T-cell lines from BH...

  16. Temporal relation of antigenaemia and loss of antibodies to core antigens to development of clinical disease in HIV infection

    DEFF Research Database (Denmark)

    Pedersen, C; Nielsen, C M; Vestergaard, B F

    1987-01-01

    count. Both antigenaemia and the disappearance of antibodies to the core protein were associated with development of the acquired immune deficiency syndrome (AIDS) or AIDS related complex and depletion of CD4 cells. Thus AIDS or AIDS related complex developed in eight out of 16 patients...... and 16 months after the estimated time of seroconversion. These results show that the late stages of HIV infection are characterised by increased production of antigen and a decrease in antibodies directed against the core protein. Antigenaemia indicates a poor prognosis; and as the antigen test...... is simple to do and interpret, it may therefore be useful for selecting patients for antiviral treatment....

  17. Blocking herpes simplex virus 2 glycoprotein E immune evasion as an approach to enhance efficacy of a trivalent subunit antigen vaccine for genital herpes.

    Science.gov (United States)

    Awasthi, Sita; Huang, Jialing; Shaw, Carolyn; Friedman, Harvey M

    2014-08-01

    Herpes simplex virus 2 (HSV-2) subunit antigen vaccines targeting virus entry molecules have failed to prevent genital herpes in human trials. Our approach is to include a virus entry molecule and add antigens that block HSV-2 immune evasion. HSV-2 glycoprotein C (gC2) is an immune evasion molecule that inhibits complement. We previously reported that adding gC2 to gD2 improved vaccine efficacy compared to the efficacy of either antigen alone in mice and guinea pigs. Here we demonstrate that HSV-2 glycoprotein E (gE2) functions as an immune evasion molecule by binding the IgG Fc domain. HSV-2 gE2 is synergistic with gC2 in protecting the virus from antibody and complement neutralization. Antibodies produced by immunization with gE2 blocked gE2-mediated IgG Fc binding and cell-to-cell spread. Mice immunized with gE2 were only partially protected against HSV-2 vaginal challenge in mice; however, when gE2 was added to gC2/gD2 to form a trivalent vaccine, neutralizing antibody titers with and without complement were significantly higher than those produced by gD2 alone. Importantly, the trivalent vaccine protected the dorsal root ganglia (DRG) of 32/33 (97%) mice between days 2 and 7 postchallenge, compared with 27/33 (82%) in the gD2 group. The HSV-2 DNA copy number was significantly lower in mice immunized with the trivalent vaccine than in those immunized with gD2 alone. The extent of DRG protection using the trivalent vaccine was better than what we previously reported for gC2/gD2 immunization. Therefore, gE2 is a candidate antigen for inclusion in a multivalent subunit vaccine that attempts to block HSV-2 immune evasion. Herpes simplex virus is the most common cause of genital ulcer disease worldwide. Infection results in emotional distress for infected individuals and their partners, is life threatening for infants exposed to herpes during childbirth, and greatly increases the risk of individuals acquiring and transmitting HIV infection. A vaccine that prevents

  18. Antigenic variation of the human influenza A (H3N2) virus during the 2014-2015 winter season.

    Science.gov (United States)

    Hua, Sha; Li, XiYan; Liu, Mi; Cheng, YanHui; Peng, YouSong; Huang, WeiJuan; Tan, MinJu; Wei, HeJiang; Guo, JunFeng; Wang, DaYan; Wu, AiPing; Shu, YueLong; Jiang, TaiJiao

    2015-09-01

    The human influenza A (H3N2) virus dominated the 2014-2015 winter season in many countries and caused massive morbidity and mortality because of its antigenic variation. So far, very little is known about the antigenic patterns of the recent H3N2 virus. By systematically mapping the antigenic relationships of H3N2 strains isolated since 2010, we discovered that two groups with obvious antigenic divergence, named SW13 (A/Switzerland/9715293/2013-like strains) and HK14 (A/Hong Kong/5738/2014-like strains), co-circulated during the 2014-2015 winter season. HK14 group co-circulated with SW13 in Europe and the United States during this season, while there were few strains of HK14 in mainland China, where SW13 has dominated since 2012. Furthermore, we found that substitutions near the receptor-binding site on hemagglutinin played an important role in the antigenic variation of both the groups. These findings provide a comprehensive understanding of the recent antigenic evolution of H3N2 virus and will aid in the selection of vaccine strains.

  19. GB virus type C interactions with HIV: the role of envelope glycoproteins

    OpenAIRE

    Mohr, Emma L.; Stapleton, Jack T.

    2009-01-01

    GB virus C/hepatitis G virus (GBV-C/HGV) is the most closely related human virus to hepatitis C virus (HCV). GBV-C is lymphotropic and not associated with any known disease, although it is associated with improved survival in HIV-infected individuals. In peripheral blood mononuclear cells, GBV-C induces the release of soluble ligands for HIV entry receptors (RANTES, MIP-1a, MIP-1b and SDF-1), suggesting that GBV-C may interact with lymphocytes to induce a chemokine and/or cytokine milieu that...

  20. Influence of the Epstein-Barr virus nuclear antigen EBNA 2 on the growth phenotype of virus-transformed B cells.

    OpenAIRE

    Rickinson, A B; Young, L S; M. Rowe

    1987-01-01

    Epstein-Barr virus (EBV) isolates show sequence divergence in the BamHI YH region of the genome which encodes the nuclear antigen EBNA 2, a protein thought to be involved in the initiation of virus-induced B-cell transformation; type A isolates (such as B95-8 EBV) encode a 82- to 87-kilodalton EBNA 2A protein, whereas type B isolates (such as AG876 EBV) encode an antigenically distinct 75-kilodalton EBNA 2B protein. In the present work 12 type A isolates and 8 type B isolates have been compar...

  1. Detection of genome, antigen, and antibodies in oral fluids from pigs infected with foot-and-mouth disease virus.

    Science.gov (United States)

    Senthilkumaran, Chandrika; Yang, Ming; Bittner, Hilary; Ambagala, Aruna; Lung, Oliver; Zimmerman, Jeffrey; Giménez-Lirola, Luis G; Nfon, Charles

    2017-04-01

    Virus nucleic acids and antibody response to pathogens can be measured using swine oral fluids (OFs). Detection of foot-and-mouth disease virus (FMDV) genome in swine OFs has previously been demonstrated. Virus isolation and viral antigen detection are additional confirmatory assays for diagnosing FMDV, but these methods have not been evaluated using swine OF. The objectives of this study were to further validate the molecular detection of FMDV in oral fluids, evaluate antigen detection and FMDV isolation from swine OFs, and develop an assay for isotypic anti-FMDV antibody detection in OFs. Ribonucleic acid (RNA) from FMDV was detected in OFs from experimentally infected pigs by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) from 1 day post-infection (dpi) to 21 dpi. Foot-and-mouth disease virus (FMDV) was isolated from OFs at 1 to 5 dpi. Additionally, FMDV antigens were detected in OFs from 1 to 6 dpi using a lateral flow immunochromatographic strip test (LFIST), which is a rapid pen-side test, and from 2 to 3 dpi using a double-antibody sandwich enzyme-linked immunosorbent assay (DAS ELISA). Furthermore, FMDV-specific immunoglobulin A (IgA) was detected in OFs using an isotype-specific indirect ELISA starting at dpi 14. These results further demonstrated the potential use of oral fluids for detecting FMDV genome, live virus, and viral antigens, as well as for quantifying mucosal IgA antibody response.

  2. [Functional analysis of hepatitis B virus immune escape mutants with insertion mutations in the surface antigen].

    Science.gov (United States)

    Yu, Shu-li; Yu, De-min; Zhang, Dong-hua; Jiang, Jie-hong; Chen, Jia; Deng, Lin; Zhang, Xin-xin

    2013-07-01

    To evaluate the influence of insertion mutations occurring in the hydrophobic region, between amino acids 114 and 115, of the hepatitis B surface antigen (HBsAg) on viral antigenicity and replication. Hepatitis B virus (HBV) DNA was obtained from patients with HBsAg-positive chronic hepatitis B (CHB) infection and subjected to sequence analysis and comparison to GenBank reference sequences for HBV genotype B (AB073826) and genotype C (AF286594). Insertion mutations detected in the HBsAg region were used to make recombinant expression plasmids via site-directed mutagenesis. After transfecting the recombinant HBsAg into Huh7 cells, the mutants' effects on viral antigenicity and replication were evaluated by chemiluminescence microparticle immunoassay (CMIA) and Southern blot hybridization, respectively. The viral antigenicity of each mutant was predicted by bioinformatic analysis, using the Jameson-Wolf method to predict the antigenic index, the Hopp-Woods method to predict hydrophilicity, the Emini method to predict the probability of a region lying of the protein's surface, and the Karplus-Schulz method to predict the flexibility of the protein backbone. Two CHB patients harbored HBV with insertion mutations in HBsAg: one with two (NT) and one with three (NTT) inserted amino acids between 114 and 115. The NTT recombinant HBsAg mutant showed no impact on viral replication and reacted weakly with anti-HBs in CMIA (P = 0.02). The antigen indices for the insertion of NTT were 1.00, -0.16, and 0.18, and insertion of the three amino acids affected the index values of five proximal amino acid sites (with an average increase of 0.13). The hydrophilic indices for the insertion of NTT were 0.2, -0.4, and -0.4, with no significant effect on the proximal amino acids. The insertion of the three amino acids changed both the surface probability (range: -0.55 to 2.97; affecting eight proximal amino acids) and the flexibility (range: -0.01 to 1.1; affecting five proximal amino

  3. Antigenic heterogeneity of capsid protein VP1 in foot-and-mouth disease virus (FMDV serotype Asia1

    Directory of Open Access Journals (Sweden)

    Alam SM

    2013-08-01

    Full Text Available SM Sabbir Alam,1 Ruhul Amin,1 Mohammed Ziaur Rahman,2 M Anwar Hossain,1 Munawar Sultana11Department of Microbiology, University of Dhaka, Dhaka, Bangladesh; 2International Centre for Diarrhoeal Disease Research, Dhaka, BangladeshAbstract: Foot and mouth disease virus (FMDV, with its seven serotypes, is a highly contagious virus infecting mainly cloven-hoofed animals. The serotype Asia1 occurs mainly in Asian regions. An in-silico approach was taken to reveal the antigenic heterogeneities within the capsid protein VP1 of Asia1. A total of 47 VP1 sequences of Asia1 isolates from different countries of South Asian regions were selected, retrieved from database, and were aligned. The structure of VP1 protein was modeled using a homology modeling approach. Several antigenic sites were identified and mapped onto the three-dimensional protein structure. Variations at these antigenic sites were analyzed by calculating the protein variability index and finding mutation combinations. The data suggested that vaccine escape mutants have derived from only few mutations at several antigenic sites. Five antigenic peptides have been identified as the least variable epitopes, with just fewer amino acid substitutions. Only a limited number of serotype Asia1 antigenic variants were found to be circulated within the South Asian region. This emphasizes a possibility of formulating synthetic vaccines for controlling foot-and-mouth disease by Asia1 serotypes.Keywords: protein modeling, antigenic sites, sequence variation

  4. Prevalence of HIV and hepatitis C virus infections among inmates of Ontario remand facilities

    National Research Council Canada - National Science Library

    Calzavara, Liviana; Ramuscak, Nancy; Burchell, Ann N; Swantee, Carol; Myers, Ted; Ford, Peter; Fearon, Margaret; Raymond, Sue

    2007-01-01

    ... (jails, detention centres and youth centres). The prevalence of HIV infection in Ontario remand facilities was last measured over a decade ago, and no research on the prevalence of hepatitis C virus (HCV...

  5. Evolution of hepatitis A virus seroprevalence among HIV-positive adults in Taiwan

    National Research Council Canada - National Science Library

    Yu-Lin Lee; Kuan-Yin Lin; Chien-Yu Cheng; Chia-Wen Li; Chia-Jui Yang; Mao-Song Tsai; Hung-Jen Tang; Te-Yu Lin; Ning-Chi Wang; Yi-Chien Lee; Shih-Ping Lin; Yu-Shan Huang; Hsin-Yun Sun; Jun-Yu Zhang; Wen-Chien Ko; Shu-Hsing Cheng; Yuan-Ti Lee; Chun-Eng Liu; Chien-Ching Hung; on behalf of the Taiwan HIV Study Group

    2017-01-01

    Objectives The study aimed to describe the seroprevalence of hepatitis A virus (HAV) in HIV-positive adult patients in Taiwan between 2012 and 2016 and to examine the evolution of HAV seroprevalence between 2004...

  6. Impact of competitive non-protective antigens in a booster killed vaccine on seroconversions to protective antigens of Newcastle disease virus in chickens

    Directory of Open Access Journals (Sweden)

    Elie K. Barbour

    2011-12-01

    Full Text Available This study was designed to examine the impact of competitive non-protective antigens in a bivalent killed vaccine of Newcastle disease virus and infectious bronchitis (IB virus on seroconversions against protective fusion protein of Newcastle disease (ND virus (NDV, in free-range layers primed by live ND-clone 30 and IB-H120 vaccines. The experimental design included two free-range layer farms in which sera of randomly chosen layers were collected on two occasions from each of the two farms namely: at the time of administration of the killed booster vaccine (23 weeks of age and three weeks later. The Western immunoblotting technique was used to react the individual pooled sera collected at different times from each farm with antigens used in priming, namely those of the ND-clone 30 virus and the IB-H120 virus. The optical density bands formed by reactions were compared statistically between seroconverted antibodies at 23 weeks with those of layers aged 26 weeks. The killed booster vaccine offered a significant seroconversion on both farms to the non-protective L-protein (248.0 kDa of NDV and on one of the two farms to the non-protective NDV-matrix protein (40.0 kDa (p<0.05. However, seroconversion to the protective fusion protein of NDV (60 kDa failed on both farms (p<0.05. In addition, on one farm, a statistical significance was revealed by the killed booster vaccine seroconversion to non-protective IBV-nucleocapsid protein (510 kDa and, on the other farm, to another non-protective IBV-glycoprotein (28.0 kDa (p<0.05. The impact of competitive seroconversions to non-protective antigens and seroconversion failures to low molecular weights of NDV protective fusion protein is discussed.

  7. Immunological changes in human immunodeficiency virus (HIV)-infected individuals during HIV-specific protease inhibitor treatment

    DEFF Research Database (Denmark)

    Ullum, H; Katzenstein, T; Aladdin, H

    1999-01-01

    The present study examines the influence of effective anti-retroviral treatment on immune function, evaluated by a broad array of immunological tests. We followed 12 individuals infected with human immunodeficiency virus (HIV) for 6 months after initiation of combination anti-retroviral treatment...... Vaccinia virus was increased after 3-6 months, whereas the specific HIV-directed CTL activity and the concentration and lytic activity of natural killer (NK) cells were unchanged during follow-up. These results demonstrate that the initiation of a treatment including an HIV protease inhibitor is followed...... count increased mainly due to increases in numbers of CD4+ CD28+ and CD4+ CD45RO+ cells, whereas increases in numbers of CD4+ CD45RA+ cells contributed little to the increase in CD4+ cell count. The total cytotoxic T-cell (CTL) killing of autologous B cells infected with HIV-encoding recombinant...

  8. Viral (hepatitis C virus, hepatitis B virus, HIV) persistence and immune homeostasis.

    Science.gov (United States)

    Zhou, Yun; Zhang, Ying; Moorman, Jonathan P; Yao, Zhi Q; Jia, Zhan S

    2014-11-01

    Immune homeostasis is a host characteristic that maintains biological balance within a host. Humans have evolved many host defence mechanisms that ensure the survival of individuals upon encountering a pathogenic infection, with recovery or persistence from a viral infection being determined by both viral factors and host immunity. Chronic viral infections, such as hepatitis B virus, hepatitis C virus and HIV, often result in chronic fluctuating viraemia in the face of host cellular and humoral immune responses, which are dysregulated by multi-faceted mechanisms that are incompletely understood. This review attempts to illuminate the mechanisms involved in this process, focusing on immune homeostasis in the setting of persistent viral infection from the aspects of host defence mechanism, including interferon-stimulated genes, apolipoprotein B mRNA editing enzyme catalytic polypeptide 3 (APOBEC3), autophagy and interactions of various immune cells, cytokines and regulatory molecules. © 2014 John Wiley & Sons Ltd.

  9. Surfactant protein D binds to human immunodeficiency virus (HIV) envelope protein gp120 and inhibits HIV replication

    DEFF Research Database (Denmark)

    Meschi, Joseph; Crouch, Erika C; Skolnik, Paul

    2005-01-01

    The envelope protein (gp120) of human immunodeficiency virus (HIV) contains highly conserved mannosylated oligosaccharides. These glycoconjugates contribute to resistance to antibody neutralization, and binding to cell surface lectins on macrophages and dendritic cells. Mannose-binding lectin (MBL......) binds to gp120 and plays a role in defence against the virus. In this study it is demonstrated that surfactant protein D (SP-D) binds to gp120 and inhibits HIV infectivity at significantly lower concentrations than MBL. The binding of SP-D was mediated by its calcium-dependent carbohydrate...... defence against HIV. A chimeric protein containing the N-terminal and collagen domains of SP-D linked to the neck and carbohydrate-recognition domains of MBL (called SP-D/MBL(neck+CRD)) had greater ability to bind to gp120 and inhibit virus replication than either SP-D or MBL. The enhanced binding of SP...

  10. Endocytosis of human immunodeficiency virus 1 (HIV-1) in astrocytes: a fiery path to its destination.

    Science.gov (United States)

    Chauhan, Ashok; Khandkar, Mehrab

    2015-01-01

    Despite successful suppression of peripheral HIV-1 infection by combination antiretroviral therapy, immune activation by residual virus in the brain leads to HIV-associated neurocognitive disorders (HAND). In the brain, several types of cells, including microglia, perivascular macrophage, and astrocytes have been reported to be infected by HIV-1. Astrocytes, the most abundant cells in the brain, maintain homeostasis. The general consensus on HIV-1 infection in astrocytes is that it produces unproductive viral infection. HIV-1 enters astrocytes by pH-dependent endocytosis, leading to degradation of the virus in endosomes, but barely succeeds in infection. Here, we have discussed endocytosis-mediated HIV-1 entry and viral programming in astrocytes. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Antigenic typing of brazilian rabies virus samples isolated from animals and humans, 1989-2000

    Directory of Open Access Journals (Sweden)

    FAVORETTO Silvana Regina

    2002-01-01

    Full Text Available Animal and human rabies samples isolated between 1989 and 2000 were typified by means of a monoclonal antibody panel against the viral nucleoprotein. The panel had been previously established to study the molecular epidemiology of rabies virus in the Americas. Samples were isolated in the Diagnostic Laboratory of the Pasteur Institute and in other rabies diagnostic centers in Brazil. In addition to the fixed virus samples CVS-31/96-IP, preserved in mouse brain, and PV-BHK/97, preserved in cell culture, a total of 330 rabies virus samples were isolated from dogs, cats, cattle, horses, bats, sheep, goat, swine, foxes, marmosets, coati and humans. Six antigenic variants that were compatible with the pre-established monoclonal antibodies panel were defined: numbers 2 (dog, 3 (Desmodus rotundus, 4 (Tadarida brasiliensis, 5 (vampire bat from Venezuela, 6 (Lasiurus cinereus and Lab (reacted to all used antibodies. Six unknown profiles, not compatible with the panel, were also found. Samples isolated from insectivore bats showed the greatest variability and the most commonly isolated variant was variant-3 (Desmodus rotundus. These findings may be related to the existence of multiple independent transmission cycles, involving different bat species.

  12. Structural and Antigenic Definition of Hepatitis C Virus E2 Glycoprotein Epitopes Targeted by Monoclonal Antibodies

    Directory of Open Access Journals (Sweden)

    Giuseppe Sautto

    2013-01-01

    Full Text Available Hepatitis C virus (HCV is the major cause of chronic liver disease as well as the major indication for liver transplantation worldwide. Current standard of care is not completely effective, not administrable in grafted patients, and burdened by several side effects. This incomplete effectiveness is mainly due to the high propensity of the virus to continually mutate under the selective pressure exerted by the host immune response as well as currently administered antiviral drugs. The E2 envelope surface glycoprotein of HCV (HCV/E2 is the main target of the host humoral immune response and for this reason one of the major variable viral proteins. However, broadly cross-neutralizing monoclonal antibodies (mAbs directed against HCV/E2 represent a promising tool for the study of virus-host interplay as well as for the development of effective prophylactic and therapeutic approaches. In the last few years many anti-HCV/E2 mAbs have been evaluated in preclinical and clinical trials as possible candidate antivirals, particularly for administration in pre- and post-transplant settings. In this review we summarize the antigenic and structural characteristics of HCV/E2 determined through the use of anti-HCV/E2 mAbs, which, given the absence of a crystal structure of this glycoprotein, represent currently the best tool available.

  13. Antigen detection in vivo after immunization with different presentation forms of rabies virus antigen, II. Cellular but not humoral systemic immune responses against rabies virus immune stimulating complexes are macrophage dependent

    NARCIS (Netherlands)

    I.J.Th.M. Claassen (Ivo); A.D.M.E. Osterhaus (Albert); M.C.M. Poelen (Martien); N. Rooijen van; H.J.H.M. Claassen (Eric)

    1998-01-01

    textabstractIn this paper we describe the effect of depletion of splenic macrophages on the uptake, and immune response against, different formulations of rabies virus antigen. Splenic macrophages were removed by intravenous injection with clodronate liposomes. beta-propiolacton inactivated rabies

  14. Seksuel transmission af hepatitis C-virus hos hiv-inficerede maend

    DEFF Research Database (Denmark)

    Peters, Lars; Weis, Nina M; Lindhardt, Bjarne Orskov

    2006-01-01

    Infections with the hepatitis C virus (HCV) occur primarily through percutaneous transmission, while sexual transmission seems to be rare. Recently, in some European cities, an increasing incidence of sexually transmitted HCV infection among HIV-infected homosexual males has been reported. We...... describe four cases of acute HCV infection among HIV-infected homosexual males, where sexual transmission was likely. Udgivelsesdato: 2006-Oct-16...

  15. The effect of human immunodeficiency virus (HIV) infection on cd4 t ...

    African Journals Online (AJOL)

    The effect of human immunodeficiency virus (HIV) infection on cd4 t-lymphocyte depletion among people living with HIV and AIDS in Enugu, Nigeria. ... group A. Though there was down regulation of viral burden during highly active antiretroviral therapy (HAART), there was no corresponding increase in T-cell proliferation.

  16. Emerging co-infection of HIV and hepatitis B virus in far western Nepal.

    Science.gov (United States)

    Poudel, Krishna C; Jimba, Masamine; Okumura, Junko; Wakai, Susumu

    2006-07-01

    We detected a prevalence (11%) of hepatitis B virus (HBV) infection among male adult villagers (n = 149) in far western Nepal where migration to India is common. Although only one migrant-returnee was infected with both HBV and HIV, co-infection may occur more frequently in future as the HIV prevalence is high (8%).

  17. Confirmation of HIV seropositivity: comparison of a novel radioimmunoprecipitation assay to immunoblotting and virus culture

    NARCIS (Netherlands)

    Tersmette, M.; Lelie, P. N.; van der Poel, C. L.; Wester, M. R.; de Goede, R. E.; Lange, J. M.; Miedema, F.; Huisman, J. G.

    1988-01-01

    A recently developed radioimmunoprecipitation assay, using 125I-labeled human immunodeficiency virus (HIV) viral proteins enriched for glycoproteins gp120env, gp41env (GRIPA), was compared to the immunoblot assay with respect to sensitivity and specificity for the detection of antibodies to HIV.

  18. Programmatic evaluation of a combined antigen and antibody test for rapid HIV diagnosis in a community and sexual health clinic screening programme.

    Science.gov (United States)

    Taegtmeyer, Miriam; MacPherson, Peter; Jones, Kathy; Hopkins, Mark; Moorcroft, Jay; Lalloo, David G; Chawla, Anu

    2011-01-01

    A substantial proportion of HIV-infected individuals in the UK are unaware of their status and late presentations continue, especially in low prevalence areas. Fourth generation antigen/antibody rapid test kits could facilitate earlier diagnosis of HIV in non-clinical settings but lack data on performance under programmatic conditions. We evaluated the performance of Determine HIV-1/2 Ag/Ab Combo Test (Determine Combo), a rapid test with indicators for both HIV antibodies and p24 antigen, in participants recruited from community outreach and hospital-based sexual health clinics. HIV infection was confirmed using laboratory enzyme-linked immunosorbent assay (EIA), Line Immuno Assay (LIA) and quantitative polymerase chain reaction (PCR). In total, 953 people underwent HIV testing. HIV antibody (Ab) prevalence was 1.8% (17/953). Four false positive rapid tests were identified: two antibody and two p24 antigen (Ag) reactions. Of participants diagnosed as HIV Ab positive, 2/17 (12%) were recent seroconverters based on clinical history and HIV antibody avidity test results. However, none of these were detected by the p24 antigen component of the rapid test kit. There were no other true positive p24 Ag tests. These data lend support to an increasing body of evidence suggesting that 4th generation rapid HIV tests have little additional benefit over 3rd generation HIV kits for routine screening in low prevalence settings and have high rates of false positives. In order to optimally combine community-based case-finding among hard-to-reach groups with reliable and early diagnosis 3rd generation kits should be primarily used with laboratory testing of individuals thought to be at risk of acute HIV infection. A more reliable point of care diagnostic is required for the accurate detection of acute HIV infection under programmatic conditions.

  19. Programmatic evaluation of a combined antigen and antibody test for rapid HIV diagnosis in a community and sexual health clinic screening programme.

    Directory of Open Access Journals (Sweden)

    Miriam Taegtmeyer

    Full Text Available BACKGROUND: A substantial proportion of HIV-infected individuals in the UK are unaware of their status and late presentations continue, especially in low prevalence areas. Fourth generation antigen/antibody rapid test kits could facilitate earlier diagnosis of HIV in non-clinical settings but lack data on performance under programmatic conditions. METHODS AND FINDINGS: We evaluated the performance of Determine HIV-1/2 Ag/Ab Combo Test (Determine Combo, a rapid test with indicators for both HIV antibodies and p24 antigen, in participants recruited from community outreach and hospital-based sexual health clinics. HIV infection was confirmed using laboratory enzyme-linked immunosorbent assay (EIA, Line Immuno Assay (LIA and quantitative polymerase chain reaction (PCR. In total, 953 people underwent HIV testing. HIV antibody (Ab prevalence was 1.8% (17/953. Four false positive rapid tests were identified: two antibody and two p24 antigen (Ag reactions. Of participants diagnosed as HIV Ab positive, 2/17 (12% were recent seroconverters based on clinical history and HIV antibody avidity test results. However, none of these were detected by the p24 antigen component of the rapid test kit. There were no other true positive p24 Ag tests. CONCLUSION: These data lend support to an increasing body of evidence suggesting that 4th generation rapid HIV tests have little additional benefit over 3rd generation HIV kits for routine screening in low prevalence settings and have high rates of false positives. In order to optimally combine community-based case-finding among hard-to-reach groups with reliable and early diagnosis 3rd generation kits should be primarily used with laboratory testing of individuals thought to be at risk of acute HIV infection. A more reliable point of care diagnostic is required for the accurate detection of acute HIV infection under programmatic conditions.

  20. Comparative evaluation of TRI-DOT Rapid HIV test with fourth-generation ELISA for the detection of human immunodeficiency virus.

    Science.gov (United States)

    Sudha, T; Teja, V D; Gopal, M; Rajesh, M; Lakshmi, V

    2005-10-01

    This study evaluated the TRI-DOT Rapid HIV test for the early detection of human immunodeficiency virus (HIV) infection in comparison with a fourth-generation ELISA (Vironostika HIV Uniform II). Of 23,609 sera, seven (0.03%) gave discordant results. Six of these were reactive only by the fourth-generation assay and were p24 antigen-positive by VIDAS DUO, Western blot and qualitative RT-PCR tests. The remaining discordant serum was considered to be false-positive by the TRI-DOT assay, as it was negative by repeat ELISA and Western blot tests. The sensitivity and specificity of the TRI-DOT test were 99.48% and 99.99%, respectively, compared with the fourth-generation ELISA.

  1. Rapid Antigen Processing and Presentation of a Protective and Immunodominant HLA-B*27-restricted Hepatitis C Virus-specific CD8+ T-cell Epitope

    Science.gov (United States)

    Schmidt, Julia; Iversen, Astrid K. N.; Tenzer, Stefan; Gostick, Emma; Price, David A.; Lohmann, Volker; Distler, Ute; Bowness, Paul; Schild, Hansjörg; Blum, Hubert E.; Klenerman, Paul

    2012-01-01

    HLA-B*27 exerts protective effects in hepatitis C virus (HCV) and human immunodeficiency virus (HIV) infections. While the immunological and virological features of HLA-B*27-mediated protection are not fully understood, there is growing evidence that the presentation of specific immunodominant HLA-B*27-restricted CD8+ T-cell epitopes contributes to this phenomenon in both infections. Indeed, protection can be linked to single immunodominant CD8+ T-cell epitopes and functional constraints on escape mutations within these epitopes. To better define the immunological mechanisms underlying HLA-B*27-mediated protection in HCV infection, we analyzed the functional avidity, functional profile, antiviral efficacy and naïve precursor frequency of CD8+ T cells targeting the immunodominant HLA-B*27-restricted HCV-specific epitope as well as its antigen processing and presentation. For comparison, HLA-A*02-restricted HCV-specific epitopes were analyzed. The HLA-B*27-restricted CD8+ T-cell epitope was not superior to epitopes restricted by HLA-A*02 when considering the functional avidity, functional profile, antiviral efficacy or naïve precursor frequency. However, the peptide region containing the HLA-B*27-restricted epitope was degraded extremely fast by both the constitutive proteasome and the immunoproteasome. This efficient proteasomal processing that could be blocked by proteasome inhibitors was highly dependent on the hydrophobic regions flanking the epitope and led to rapid and abundant presentation of the epitope on the cell surface of antigen presenting cells. Our data suggest that rapid antigen processing may be a key immunological feature of this protective and immunodominant HLA-B*27-restricted HCV-specific epitope. PMID:23209413

  2. Antigenic drift of the pandemic 2009 A(H1N1 influenza virus in A ferret model.

    Directory of Open Access Journals (Sweden)

    Teagan Guarnaccia

    Full Text Available Surveillance data indicate that most circulating A(H1N1pdm09 influenza viruses have remained antigenically similar since they emerged in humans in 2009. However, antigenic drift is likely to occur in the future in response to increasing population immunity induced by infection or vaccination. In this study, sequential passaging of A(H1N1pdm09 virus by contact transmission through two independent series of suboptimally vaccinated ferrets resulted in selection of variant viruses with an amino acid substitution (N156K, H1 numbering without signal peptide; N159K, H3 numbering without signal peptide; N173K, H1 numbering from first methionine in a known antigenic site of the viral HA. The N156K HA variant replicated and transmitted efficiently between naïve ferrets and outgrew wildtype virus in vivo in ferrets in the presence and absence of immune pressure. In vitro, in a range of cell culture systems, the N156K variant rapidly adapted, acquiring additional mutations in the viral HA that also potentially affected antigenic properties. The N156K escape mutant was antigenically distinct from wildtype virus as shown by binding of HA-specific antibodies. Glycan binding assays demonstrated the N156K escape mutant had altered receptor binding preferences compared to wildtype virus, which was supported by computational modeling predictions. The N156K substitution, and culture adaptations, have been detected in human A(H1N1pdm09 viruses with N156K preferentially reported in sequences from original clinical samples rather than cultured isolates. This study demonstrates the ability of the A(H1N1pdm09 virus to undergo rapid antigenic change to evade a low level vaccine response, while remaining fit in a ferret transmission model of immunization and infection. Furthermore, the potential changes in receptor binding properties that accompany antigenic changes highlight the importance of routine characterization of clinical samples in human A(H1N1pdm09 influenza

  3. Development of dengue virus replicons expressing HIV-1 gp120 and other heterologous genes: a potential future tool for dual vaccination against dengue virus and HIV

    Directory of Open Access Journals (Sweden)

    Dayton Andrew I

    2001-11-01

    Full Text Available Abstract Background Toward the goals of providing an additional vector to add to the armamentarium available to HIV vaccinologists and of creating a bivalent vaccine effective against dengue virus and HIV, we have attempted to create vectors which express dengue virus non-structural proteins and HIV immunogens. Previously we reported the successful construction of dengue virus replicons which lack structural genes necessary for virion release and spreading infection in culture but which can replicate intracellularly and abundantly produce dengue non-structural proteins. Here we attempted to express heterologous genetic material from these replicons. Results We cloned into a Δpre-M/E dengue virus replicon genes for either green fluorescent protein (GFP, HIV gp160 or HIV gp120 and tested the ability of these constructs to express dengue virus proteins as well as the heterologous proteins in tissue culture after transfection of replicon RNA. Conclusions Heterologous proteins were readily expressed from these constructs. GFP and gp120 demonstrated minimal or no toxicity. Gp160 expressing replicons were found to express proteins abundantly at 36 hours post transfection, but after 50 hrs of transfection, few replicon positive cells could be found despite the presence of cellular debris positive for replicon proteins. This suggested that gp160 expressed from dengue virus replicons is considerably more toxic than either GFP or gp120. The successful expression of heterologous proteins, including HIV gp120 for long periods in culture suggests this vector system may be useful as a vaccine vector, given appropriate delivery methods.

  4. Seroepidemiology of herpes simplex virus type 2 (HSV2) in HIV infected patients in Kermanshah-Iran

    OpenAIRE

    Janbakhash, Alireza; Mansouri, Feizollah; Vaziri, Siavash; Sayad, Babak; Afsharian, Mandana; Abedanpor, Ahmadreza

    2012-01-01

    Background: HSV2 has an important role in acquiring and transmitting HIV through genital ulcers. This study was conducted to determine the prevalence of this virus in HIV infected subject in Kermanshah, Iran.

  5. Development of influenza A(H7N9) candidate vaccine viruses with improved hemagglutinin antigen yield in eggs

    Science.gov (United States)

    Ridenour, Callie; Johnson, Adam; Winne, Emily; Hossain, Jaber; Mateu-Petit, Guaniri; Balish, Amanda; Santana, Wanda; Kim, Taejoong; Davis, Charles; Cox, Nancy J; Barr, John R; Donis, Ruben O; Villanueva, Julie; Williams, Tracie L; Chen, Li-Mei

    2015-01-01

    Background The emergence of avian influenza A(H7N9) virus in poultry causing zoonotic human infections was reported on March 31, 2013. Development of A(H7N9) candidate vaccine viruses (CVV) for pandemic preparedness purposes was initiated without delay. Candidate vaccine viruses were derived by reverse genetics using the internal genes of A/Puerto/Rico/8/34 (PR8). The resulting A(H7N9) CVVs needed improvement because they had titers and antigen yields that were suboptimal for vaccine manufacturing in eggs, especially in a pandemic situation. Methods Two CVVs derived by reverse genetics were serially passaged in embryonated eggs to improve the hemagglutinin (HA) antigen yield. The total viral protein and HA antigen yields of six egg-passaged CVVs were determined by the BCA assay and isotope dilution mass spectrometry (IDMS) analysis, respectively. CVVs were antigenically characterized by hemagglutination inhibition (HI) assays with ferret antisera. Results Improvement of total viral protein yield was observed for the six egg-passaged CVVs; HA quantification by IDMS indicated approximately a twofold increase in yield of several egg-passaged viruses as compared to that of the parental CVV. Several different amino acid substitutions were identified in the HA of all viruses after serial passage. However, HI tests indicated that the antigenic properties of two CVVs remained unchanged. Conclusions If influenza A(H7N9) viruses were to acquire sustained human-to-human transmissibility, the improved HA yield of the egg-passaged CVVs generated in this study could expedite vaccine manufacturing for pandemic mitigation. PMID:25962412

  6. Antigenicity of the 2015-2016 seasonal H1N1 human influenza virus HA and NA proteins.

    Directory of Open Access Journals (Sweden)

    Amelia M Clark

    Full Text Available Antigenic drift of the hemagglutinin (HA and neuraminidase (NA influenza virus proteins contributes to reduced vaccine efficacy. To analyze antigenic drift in human seasonal H1N1 viruses derived from the 2009 pandemic H1N1 virus (pH1N1-like viruses accounts for the limited effectiveness (around 40% of vaccination against pH1N1-like viruses during the 2015-2016 season, nasal washes/swabs collected from adult subjects in the Rochester, NY area, were used to sequence and isolate the circulating viruses. The HA and NA proteins from viruses circulating during the 2015-2016 season encoded eighteen and fourteen amino acid differences, respectively, when compared to A/California/04/2009, a strain circulating at the origin of the 2009 pandemic. The circulating strains belonged to subclade 6B.1, defined by HA amino acid substitutions S101N, S179N, and I233T. Hemagglutination-inhibiting (HAI and HA-specific neutralizing serum antibody (Ab titers from around 50% of pH1N1-like virus-infected subjects and immune ferrets were 2-4 fold lower for the 2015-2016 circulating strains compared to the vaccine strain. In addition, using a luminex-based mPlex HA assay, the binding of human sera from subjects infected with pH1N1-like viruses to the HA proteins from circulating and vaccine strains was not identical, strongly suggesting antigenic differences in the HA protein. Additionally, NA inhibition (NAI Ab titers in human sera from pH1N1-like virus-infected subjects increased after the infection and there were measurable antigenic differences between the NA protein of circulating strains and the vaccine strain using both ferret and human antisera. Despite having been vaccinated, infected subjects exhibited low HAI Ab titers against the vaccine and circulating strains. This suggests that poor responses to the H1N1 component of the vaccine as well as antigenic differences in the HA and NA proteins of currently circulating pH1N1-like viruses could be contributing to

  7. HIV incidence in the Estonian population in 2013 determined using the HIV-1 limiting antigen avidity assay.

    Science.gov (United States)

    Soodla, P; Simmons, R; Huik, K; Pauskar, M; Jõgeda, E-L; Rajasaar, H; Kallaste, E; Maimets, M; Avi, R; Murphy, G; Porter, K; Lutsar, I

    2017-08-01

    Estonia has one the highest number of new HIV diagnoses in the European Union, mainly among injecting drug users and heterosexuals. Little is known of HIV incidence, which is crucial for limiting the epidemic. Using a recent HIV infection testing algorithm (RITA) assay, we aimed to estimate HIV incidence in 2013. All individuals aged ≥18 years newly-diagnosed with HIV in Estonia January- December 2013, except blood donors and those undergoing antenatal screening, were included. Demographic and clinical data were obtained from the Estonian Health Board and the Estonian HIV-positive patient database. Serum samples were tested for recent infection using the LAg-avidity EIA assay. HIV incidence was estimated based on previously published methods. Of 69,115 tested subjects, 286 (0.41%) were newly-diagnosed with HIV with median age of 33 years (IQR: 28-42) and 65% male. Self-reported routes of HIV transmission were mostly heterosexual contact (n = 157, 53%) and injecting drug use (n = 62, 21%); 64 (22%) were with unknown risk group. Eighty two (36%) were assigned recent, resulting in estimated HIV incidence of 0.06%, corresponding to 642 new infections in 2013 among the non-screened population. Incidence was highest (1.48%) among people who inject drugs. These high HIV incidence estimates in Estonia call for urgent action of renewed targeted public health promotion and HIV testing campaigns. © 2017 British HIV Association.

  8. Molecular characterisation of hepatitis B virus in HIV-1 subtype C infected patients in Botswana.

    Science.gov (United States)

    Anderson, Motswedi; Gaseitsiwe, Simani; Moyo, Sikhulile; Wessels, Matthijs J C; Mohammed, Terence; Sebunya, Theresa K; Powell, Eleanor A; Makhema, Joseph; Blackard, Jason T; Marlink, Richard; Essex, Max; Musonda, Rosemary M

    2015-08-13

    Hepatitis B virus (HBV) is a major global health problem especially in sub-Saharan Africa and in East Asia. Ten hepatitis B virus genotypes have been described that differ by geographic distribution, disease progression, and response to treatment. Escape mutations within the surface open reading frame (ORF) affect HBV antigenicity leading to failures in diagnosis, vaccine and hepatitis B immunoglobulin therapy. However, the molecular characteristics of HBV in Botswana, a highly endemic country, are unknown. We describe the molecular characteristics of HBV and prevalence of escape mutants among HIV/HBV coinfected individuals Botswana. DNA was extracted from archived plasma samples from 81 HIV/HBV co-infected participants from various clinical studies at the Botswana Harvard AIDS Institute Partnership. A 415 base pair (bp) fragment of the polymerase gene was amplified by semi-nested PCR. In a subset of samples, a 2100 bp fragment was amplified. The PCR product was genotyped using Big Dye sequencing chemistry and the sequences were analysed for genotypes and mutations. Of the 81 samples included, 70 (86 %) samples were successfully genotyped. Genotype A was found in 56 (80 %) participants, D in 13 (18.6 %), and 1 (1.4 %) was genotype E. Escape mutations previously linked with failure of diagnosis or escaping active vaccination and passive immunoglobulin therapy were detected in 12 (17.1 %) participants at positions 100, 119, 122, 123, 124, 126, 129, 130, 133, 134 and 140 of the S ORF. Genotypes and escape mutations were not significantly associated with aspartate aminotransferase (AST), alanine aminotransferase (ALT) and AST platelet ratio index (APRI). Genotypes A, D and E were found in this cohort of HIV coinfected patients in Botswana, consistent with the findings from the sub-Saharan Africa region. Some escape mutations which have previously been associated with diagnosis failure, escaping vaccine and immunoglobulin therapy were also observed and are important in

  9. T-cell subset alterations and lymphocyte responsiveness to mitogens and antigen during severe primary infection with HIV: a case series of seven consecutive HIV seroconverters

    DEFF Research Database (Denmark)

    Pedersen, C; Dickmeiss, E; Gaub, J

    1990-01-01

    Seven consecutive patients who presented with a severe acute mononucleosis-like illness associated with HIV seroconversion were evaluated by T-cell subset enumerations and measurements of lymphocyte transformation responses to mitogens and antigen during both their primary illness and a 1-year...... follow-up period. We observed a characteristic pattern of response to primary HIV infection; initial lymphopenia was followed by CD8 lymphocytosis and inversion of the CD4:CD8 ratio. During follow-up, the CD8 count gradually returned to normal, whereas the CD4:CD8 ratio remained inverted because....... We conclude that severe primary HIV infection may be followed by sustained lymphocyte hyporesponsiveness, a sustained low percentage of CD4 lymphocytes and sustained inversion of the CD4:CD8 ratio....

  10. Antiviral CD8+ T Cells Restricted by Human Leukocyte Antigen Class II Exist during Natural HIV Infection and Exhibit Clonal Expansion.

    Science.gov (United States)

    Ranasinghe, Srinika; Lamothe, Pedro A; Soghoian, Damien Z; Kazer, Samuel W; Cole, Michael B; Shalek, Alex K; Yosef, Nir; Jones, R Brad; Donaghey, Faith; Nwonu, Chioma; Jani, Priya; Clayton, Gina M; Crawford, Frances; White, Janice; Montoya, Alana; Power, Karen; Allen, Todd M; Streeck, Hendrik; Kaufmann, Daniel E; Picker, Louis J; Kappler, John W; Walker, Bruce D

    2016-10-18

    CD8+ T cell recognition of virus-infected cells is characteristically restricted by major histocompatibility complex (MHC) class I, although rare examples of MHC class II restriction have been reported in Cd4-deficient mice and a macaque SIV vaccine trial using a recombinant cytomegalovirus vector. Here, we demonstrate the presence of human leukocyte antigen (HLA) class II-restricted CD8+ T cell responses with antiviral properties in a small subset of HIV-infected individuals. In these individuals, T cell receptor β (TCRβ) analysis revealed that class II-restricted CD8+ T cells underwent clonal expansion and mediated killing of HIV-infected cells. In one case, these cells comprised 12% of circulating CD8+ T cells, and TCRα analysis revealed two distinct co-expressed TCRα chains, with only one contributing to binding of the class II HLA-peptide complex. These data indicate that class II-restricted CD8+ T cell responses can exist in a chronic human viral infection, and may contribute to immune control. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  11. Humoral immune responses to Pneumocystis jirovecii antigens in HIV-infected and uninfected young children with pneumocystis pneumonia.

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    Kpandja Djawe

    Full Text Available Humoral immune responses in human immunodeficiency virus (HIV-infected and uninfected children with Pneumocystis pneumonia (PcP are poorly understood.Consecutive children hospitalized with acute pneumonia, tachypnea, and hypoxia in South Africa were investigated for PcP, which was diagnosed by real-time polymerase chain reaction on lower respiratory tract specimens. Serum antibody responses to recombinant fragments of the carboxyl terminus of Pneumocystis jirovecii major surface glycoprotein (MsgC were analyzed.149 children were enrolled of whom 96 (64% were HIV-infected. PcP occurred in 69 (72% of HIV-infected and 14 (26% of HIV-uninfected children. HIV-infected children with PcP had significantly decreased IgG antibodies to MsgC compared to HIV-infected patients without PcP, but had similar IgM antibodies. In contrast, HIV-uninfected children with PcP showed no change in IgG antibodies to MsgC, but had significantly increased IgM antibodies compared to HIV-uninfected children without PCP. Age was an independent predictor of high IgG antibodies, whereas PcP was a predictor of low IgG antibodies and high IgM antibodies. IgG and IgM antibody levels to the most closely related MsgC fragments were predictors of survival from PcP.Young HIV-infected children with PcP have significantly impaired humoral immune responses to MsgC, whereas HIV-uninfected children with PcP can develop active humoral immune responses. The children also exhibit a complex relationship between specific host factors and antibody levels to MsgC fragments that may be related to survival from PcP.

  12. A mathematical model of HIV dynamics in the presence of a rescuing virus with replication deficiency.

    Science.gov (United States)

    Zintzaras, Elias; Kowald, Axel

    2011-06-01

    Recently, an enzyme (Cre recombinase) has been developed by directed evolution that successfully removes the HIV genome from the nuclear DNA of infected cells. To explore this idea further, we hypothesized that a replication deficient virus (called "police virus"), added externally, can deliver such a recombinase which excises the integrated HIV DNA from the genome of infected cells. Such a "police virus" could attack and remove the integrated provirus which is not possible using contemporary strategies. The hypothesis was tested by developing a mathematical model that describes the dynamics of virus-host cell interaction and the consequences of introducing the "police virus". The simulations show that such a therapeutic vector may eradicate all HIV viruses from the system in the long term. All components of the HIV infection (free virus, latently, and actively infected cells) can be cleared and the system ends up only with susceptible CD4+ cells. The proposed model may provide new insights in the dynamical behavior and future alternative treatments of HIV.

  13. Safety profile of the viral vectors of attenuated fowlpox strain FP9 and modified vaccinia virus Ankara recombinant for either of 2 preerythrocytic malaria antigens, ME-TRAP or the circumsporozoite protein, in children and adults in Kenya.

    Science.gov (United States)

    Bejon, Philip; Peshu, Norbert; Gilbert, Sarah C; Lowe, Brett S; Molyneux, Catherine S; Forsdyke, John; Lang, Trudie; Hill, Adrian V S; Marsh, Kevin

    2006-04-15

    We are developing a heterologous prime-boost vaccine strategy against malaria. This approach uses sequential immunization with different vectors to deliver a common preerythrocytic malaria antigen. Preliminary evidence of efficacy and safety has been previously documented in studies from an area where malaria is nonendemic. Additional safety data from an area where malaria is endemic are now required before larger-scale studies are undertaken to determine the efficacy of this vaccine strategy in the field. Other modified vaccinia virus Ankara (MVA) recombinants and prime-boost immunizations are being developed as vaccines against human immunodeficiency virus (HIV) infection, tuberculosis, and cancer, and MVA is a candidate attenuated smallpox vaccine. Candidate vaccines against malaria were intradermally administered to 73 adults (7 of whom were HIV positive) and 22 children in Kenya. These vaccines used the attenuated fowlpox strain FP9 and the MVA recombinant for either of 2 preerythrocytic malaria antigens, multiple preerythrocytic-stage epitopes joined with the preerythrocytic-stage antigen TRAP (ME-TRAP) and the circumsporozoite protein (CS). Adverse events were recorded. Reactogenicity was mild. MVA caused less frequent and less severe cutaneous reaction if given after FP9 priming. Half doses reduced the frequency and the severity of systemic reactogenicity, and particular vaccine lots were associated with different reactogenicities. Unexpectedly, prior immunity to the ME-TRAP antigen appeared to be protective against local reactions after immunization. Where the final intention is to use MVA after FP9 priming, previous testing of MVA alone overestimates reactogenicity. These recombinant vectors appear to be safe and suitable for use in larger-scale studies of children in Africa and of HIV-positive individuals.

  14. Involvement of lymphocyte function-associated antigen-1 (LFA-1) in HIV infection: inhibition by monoclonal antibody

    DEFF Research Database (Denmark)

    Hansen, J E; Nielsen, C; Mathiesen, Lars Reinhardt

    1991-01-01

    Monoclonal antibodies (MAbs) against the alpha- and beta-chain of lymphocyte-associated antigen-1 (LFA-1) were examined for inhibition of HIV-1 infection in vitro. Infection of the T cell line MT4 and the monocytic cell line U937 by isolates HTLVIIIB and SSI-002, respectively was inhibited...... in a concentration dependent manner by MAb against the beta-chain but not against the alpha-chain. No cross-reactivity was found between MAb against LFA-1 and against the CD4 receptor (MAb Leu3a). MAbs against the beta-chain and the CD4 receptor were found to act synergistically in inhibiting HIV infection....... These data indicate that the beta-chain of LFA-1 in addition to the CD4 receptor may be involved in HIV infection in vitro....

  15. Yeast expressing hepatitis B virus surface antigen determinants on its surface: Implications for a possible oral vaccine

    NARCIS (Netherlands)

    Schreuder, M.P.; Deen, C.; Boersma, W.J.A.; Pouwels, P.H.; Klis, F.M.

    1996-01-01

    The two major hydrophilic regions of the hepatitis B virus surface antigen (HBsAg) have been expressed in the outer mannoprotein layer of the cell wall of 'Bakers Yeast', Saccharomyces cerevisiae, by fusing them between the yeast invertase signal sequence and the yeast α-agglutinin carboxyterminal

  16. Reduced response to Epstein-Barr virus antigens by T-cells in systemic lupus erythematosus patients

    DEFF Research Database (Denmark)

    Draborg, Anette Holck; Jacobsen, Søren; Westergaard, Marie

    2014-01-01

    OBJECTIVE: Epstein-Barr virus (EBV) has for long been associated with systemic lupus erythematosus (SLE). In this study, we investigated the levels of latent and lytic antigen EBV-specific T-cells and antibodies in SLE patients. METHODS: T cells were analyzed by flow cytometry and antibodies were...

  17. Studies of the Antigenic relationships between Bluetongue virus serotypes 2, 9 AND 15 isolated in Andhra Pradesh, India

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    Sreenivasulu Daggupati

    Full Text Available The presence of multiple serotypes of the midge-borne bluetongue virus and lack of effective vaccine are the major impediments in controlling bluetongue in sheep. Attempts are being made to develop a vaccine employing the available serotypes to control the disease in the state. Hence, it is essential to identify the antigenic relationships among the serotypes to identify the candidate strains to be incorporated in the preparation of vaccine. To understand the antigenic relationships between Bluetongue virus -2, 9 and 15 serotypes, the viruses were propagated in BHK21 cell lines, purified using PEG precipitation method and purified virus used to raise hyper immune serum in rabbits. Neutralizing antibodies for the BTV serotypes were detected by day 21 PI. Reciprocal cross neutralization test was employed to determine the R% values between BTV-2, 9 and 15 which indicated the extent of antigenic relationships among the serotypes. R% value between BTV-2 and BTV-9 was recorded as 2.8. R% value of 3.53 and 2.8 were observed between BTV-2 & 15 and BTV-9 & 15 respectively. The R% values recorded in the present study revealed a weak antigenic relationship between the BTV serotypes,indicating that the serotypes are highly divergent. [Vet. World 2011; 4(10.000: 444-448

  18. Molecular characterization of Torque teno virus and SEN virus co-infection with HIV in patients from Southern Iran

    Directory of Open Access Journals (Sweden)

    Aliyar Pirouzi

    2014-06-01

    Full Text Available Introduction Torque teno virus (TTV and SEN virus are circular single-stranded DNA viruses that cause blood-borne infections. The SEN virus (SEN-V was originally detected in the serum of an injection drug user infected with human immunodeficiency virus (HIV. Recently TTV was discovered as a potential causative agent of non-A-E hepatitis. The aim of this study was to investigate the prevalence of the SEN-V-D/H and TTV in HIV patients and healthy blood donors in Iran. Methods One hundred and fifty HIV patients with a mean age of 50.46 ± 18.46 years and 150 healthy blood donors with a mean age of 48.16 ± 13.73 years were included in this study. TTV and SEN-V were detected by the PCR and were quantitatively assayed by competitive PCR (nested and semi-nested PCR. Restriction fragment length polymorphisms (RFLPs were used to determine the heterogeneity of TTV. Results TTV and SEN-V were detected 96 (64% and 84 (56% of 150 HIV patients respectively. These rates were 34% (n=51 and 37.33% (n=56 in healthy blood donors (significant, p<0.05. PCR detected SEN-V/TTV DNA from 32 of the healthy blood donors (21.33%, while 65 (43.33% of HIV patients were positive for SEN-V/TTV DNA. Of 150 HIV patients, 32.66% and 23.33% were positive for SEN-V-H and SEN-V-D, respectively and 18.66% (n=28 were co-infected with SEN-V-D/H. Conclusions The prevalence of SEN-VD/H and TTV is higher in HIV patients than in healthy blood donors in Southern Iran. Our results suggest that TTV and SEN-V might play a role in the development of liver disease in patients with immunodeficiency diseases.

  19. Simian virus 40 large tumor antigen modulates the Raf signaling pathway.

    Science.gov (United States)

    Grammatikakis, N; Jaronczyk, K; Siganou, A; Vultur, A; Brownell, H L; Benzaquen, M; Rausch, C; Lapointe, R; Gjoerup, O; Roberts, T M; Raptis, L

    2001-07-27

    The large tumor antigen of simian virus 40 (SVLT) is a potent oncogene. Although inactivation of the p53 and pRb tumor suppressors has been causally linked to the transforming properties of SVLT, its exact mechanism of action remains undefined. Previous data indicated that Ras is activated in SVLT-expressing cells. In this report we show that SVLT also increases Raf kinase activity in both insect and mammalian cells, thus identifying the Raf kinase as an additional target of SVLT. Our results further show that SVLT was still able to activate Raf in cells where Ras levels had been drastically reduced through expression of an antisense construct, indicating that SVLT may activate Raf at least partly by a mechanism that is independent of its stimulatory effect on Ras.

  20. Structural, antigenic and immunogenic features of respiratory syncytial virus glycoproteins relevant for vaccine development

    Science.gov (United States)

    Melero, José A.; Mas, Vicente; McLellan, Jason S.

    2016-01-01

    Extraordinary progress in the structure and immunobiology of the human respiratory syncytial virus glycoproteins has been accomplished during the last few years. Determination of the fusion (F) glycoprotein structure folded in either the prefusion or the postfusion conformation was an inspiring breakthrough not only to understand the structural changes associated with the membrane fusion process but additionally to appreciate the antigenic intricacies of the F molecule. Furthermore, these developments have opened new avenues for structure-based designs of promising hRSV vaccine candidates. Finally, recent advances in our knowledge of the attachment (G) glycoprotein and its interaction with cell-surface receptors have revitalized interest in this molecule as a vaccine, as well as its role in hRSV immunobiology. PMID:27692522

  1. Preferential Targeting of Conserved Gag Regions after Vaccination with a Heterologous DNA Prime-Modified Vaccinia Virus Ankara Boost HIV-1 Vaccine Regimen.

    Science.gov (United States)

    Bauer, Asli; Podola, Lilli; Mann, Philipp; Missanga, Marco; Haule, Antelmo; Sudi, Lwitiho; Nilsson, Charlotta; Kaluwa, Bahati; Lueer, Cornelia; Mwakatima, Maria; Munseri, Patricia J; Maboko, Leonard; Robb, Merlin L; Tovanabutra, Sodsai; Kijak, Gustavo; Marovich, Mary; McCormack, Sheena; Joseph, Sarah; Lyamuya, Eligius; Wahren, Britta; Sandström, Eric; Biberfeld, Gunnel; Hoelscher, Michael; Bakari, Muhammad; Kroidl, Arne; Geldmacher, Christof

    2017-09-15

    Prime-boost vaccination strategies against HIV-1 often include multiple variants for a given immunogen for better coverage of the extensive viral diversity. To study the immunologic effects of this approach, we characterized breadth, phenotype, function, and specificity of Gag-specific T cells induced by a DNA-prime modified vaccinia virus Ankara (MVA)-boost vaccination strategy, which uses mismatched Gag immunogens in the TamoVac 01 phase IIa trial. Healthy Tanzanian volunteers received three injections of the DNA-SMI vaccine encoding a subtype B and AB-recombinant Gagp37 and two vaccinations with MVA-CMDR encoding subtype A Gagp55 Gag-specific T-cell responses were studied in 42 vaccinees using fresh peripheral blood mononuclear cells. After the first MVA-CMDR boost, vaccine-induced gamma interferon-positive (IFN-γ+) Gag-specific T-cell responses were dominated by CD4+ T cells (P viruses. While including multiple variants for a given immunogen in prime-boost vaccination strategies is one approach that aims to improve coverage for global virus variants, the immunologic consequences of this strategy have been poorly defined so far. It is unclear whether inclusion of multiple variants in prime-boost vaccination strategies improves recognition of variant viruses by T cells and by which mechanisms this would be achieved, either by improved cross-recognition of multiple variants for a given antigenic region or through preferential targeting of antigenic regions more conserved between prime and boost. Engineering vaccines to induce adaptive immune responses that preferentially target conserved antigenic regions of viral vulnerability might facilitate better immune control after preventive and therapeutic vaccination for HIV and for other variable viruses. Copyright © 2017 American Society for Microbiology.

  2. Rapid Detection and Differentiation of Antibodies to HIV-1 and HIV-2 Using Multivalent Antigens and Magnetic Immunochromatography Testing▿

    Science.gov (United States)

    Granade, Timothy C.; Workman, Shon; Wells, Susan K.; Holder, Angela N.; Owen, S. Michele; Pau, Chou-Pong

    2010-01-01

    A simplified lateral-flow assay for the detection of antibodies to HIV using magnetic-bead conjugates and multibranched peptides from both HIV-1 and HIV-2 was developed. Magnetic immunochromatography testing (MICT) uses a standard lateral-flow platform that incorporates magnetic-bead conjugates for quantitative measurement of the magnetic field distortion associated with the bound magnetic conjugate (reported as adjusted relative magnetic units [MAR]). The results of the optimized MICT assay were compared to standard enzyme immunoassay (EIA) and Western blotting (WB) results using a blinded 649-member panel of specimens from the United States, Cameroon, and West Africa. The panel was comprised of samples from individuals infected with various HIV-1 subtypes (n = 234) or HIV-2 (n = 65) and HIV-seronegative specimens (n = 350). Additionally, 13 HIV-1 seroconversion panels (total specimens = 85), a worldwide panel containing seven of the major circulating HIV-1 subtypes (n = 18), an HIV-2 panel, an HIV-1/HIV-2 mixed panel, and 100 prospective specimens were tested with completely concordant results. Assay reproducibility (observed MAR) for both intra- and interrun testing was excellent, with coefficients of variation of HIV antibody status requiring no subjective interpretations. PMID:20410326

  3. Myristoylation increases the CD8+T-cell response to a GFP prototype antigen delivered by modified vaccinia virus Ankara.

    Science.gov (United States)

    Marr, Lisa; Lülf, Anna-Theresa; Freudenstein, Astrid; Sutter, Gerd; Volz, Asisa

    2016-04-01

    Activation of CD8(+)T-cells is an essential part of immune responses elicited by recombinant modified vaccinia virus Ankara (MVA). Strategies to enhance T-cell responses to antigens may be particularly necessary for broadly protective immunization against influenza A virus infections or for candidate vaccines targeting chronic infections and cancer. Here, we tested recombinant MVAs that targeted a model antigen, GFP, to different localizations in infected cells. In vitro characterization demonstrated that GFP accumulated in the nucleus (MVA-nls-GFP), associated with cellular membranes (MVA-myr-GFP) or was equally distributed throughout the cell (MVA-GFP). On vaccination, we found significantly higher levels of GFP-specific CD8(+)T-cells in MVA-myr-GFP-vaccinated BALB/c mice than in those immunized with MVA-GFP or MVA-nls-GFP. Thus, myristoyl modification may be a useful strategy to enhance CD8(+)T-cell responses to MVA-delivered target antigens.

  4. Prokaryotic Expression, Purification and Immunogenicity in Rabbits of the Small Antigen of Hepatitis Delta Virus

    Directory of Open Access Journals (Sweden)

    Vera L. Tunitskaya

    2016-10-01

    Full Text Available Hepatitis delta virus (HDV is a viroid-like blood-borne human pathogen that accompanies hepatitis B virus infection in 5% patients. HDV has been studied for four decades; however, the knowledge on its life-cycle and pathogenesis is still sparse. The studies are hampered by the absence of the commercially-available HDV-specific antibodies. Here, we describe a set of reproducible methods for the expression in E. coli of His-tagged small antigen of HDV (S-HDAg, its purification, and production of polyclonal anti-S-HDAg antibodies in rabbits. S-HDAg was cloned into a commercial vector guiding expression of the recombinant proteins with the C-terminal His-tag. We optimized S-HDAg protein purification procedure circumventing a low affinity of the His-tagged S-HDAg to the Ni-nitrilotriacetyl agarose (Ni-NTA-agarose resin. Optimization allowed us to obtain S-HDAg with >90% purity. S-HDAg was used to immunize Shinchilla grey rabbits which received 80 μg of S-HDAg in two subcutaneous primes in the complete, followed by four 40 μg boosts in incomplete Freunds adjuvant. Rabbits were bled two weeks post each boost. Antibody titers determined by indirect ELISA exceeded 107. Anti-S-HDAg antibodies detected the antigen on Western blots in the amounts of up-to 100 pg. They were also successfully used to characterize the expression of S-HDAg in the eukaryotic cells by immunofluorescent staining/confocal microscopy.

  5. Lack of Epstein-Barr virus- and HIV-specific CD27- CD8+ T cells is associated with progression to viral disease in HIV-infection

    NARCIS (Netherlands)

    van Baarle, Debbie; Kostense, Stefan; Hovenkamp, Egbert; Ogg, Graham; Nanlohy, Nening; Callan, Margaret F. C.; Dukers, Nicole H. T. M.; McMichael, Andrew J.; van Oers, Marinus H. J.; Miedema, Frank

    2002-01-01

    OBJECTIVE: Despite readily detectable virus-specific CD8+ T cells in most HIV-infected patients, immune surveillance is eventually lost, leading to progression to AIDS. To investigate the underlying mechanism of this loss of immune control phenotypic analysis of HIV- and Epstein-Barr virus

  6. A Single Amino Acid Substitution Changes Antigenicity of ORF2-Encoded Proteins of Hepatitis E Virus

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    Ji-Hong Meng

    2010-08-01

    Full Text Available Extensive genomic diversity has been observed among hepatitis E virus (HEV strains. However, the implication of the genetic heterogeneity on HEV antigenic properties is uncertain. In this study, monoclonal antibodies (Mabs against truncated ORF2-encoded proteins (aa452‑617, designated p166 proteins derived from HEV strains of Burma (genotype 1a, p166Bur, Pakistan (1b, p166Pak and Morocco (1c, p166Mor were raised and used for identification of HEV antigenic diversity. Six Mabs reacted to these 3 p166 proteins as well as p166 proteins constructed from strains derived from Mexico (genotype 2, US (genotype 3 and China (genotype 4, indicating the existence of pan‑genotypic epitopes. Two Mabs, 1B5 and 6C7, reacted with p166Bur and p166Mor, but not p166Pak or p166s derived from genotypes 2, 3, and 4, indicating that these 2 Mabs recognized strain-specific HEV epitopes. Both the common and specific epitopes could not be mapped by 23 synthetic peptides spanning the p166Bur sequence, suggesting that they are confirmation‑dependent. Comparative sequence analysis showed that p166Bur and p166Mor shared an identical aa sequence along their entire lengths, whereas for p166Pak the aas occupying positions 606 and 614 are different from aas at corresponding positions of p166Bur and p166Mor. Reactivity between 1B5 and p166Bur was abrogated with mutation of p166Bur/A606V, whereas p166Pak acquired the reactivity to 1B5 with mutation of p166Pak/V606A. However, mutations of p166Bur/L614M and P166Pak/M614L did not affect the immunoreactivity. Therefore, the aa occupying position 606 plays a critical role in maintaining the antigenicity of the HEV p166 proteins.

  7. Generation of hepatitis B virus PreS2-S antigen in Hansenula polymorpha.

    Science.gov (United States)

    Xu, Xiaowei; Ren, Sulin; Chen, Xiaoxiao; Ge, Jun; Xu, Zhenxing; Huang, Hongying; Sun, Honglin; Gu, Yue; Zhou, Tong; Li, Jianqiang; Xu, Hanmei

    2014-12-01

    Despite the long availability of a traditional prophylactic vaccine containing the HBV surface antigen (HBsAg) and aluminum adjuvant, nearly 10% of the population remains unable to generate an effective immune response. Previous studies have indicated that hepatitis B virus (HBV) PreS2-S is abundant in T/B cell epitopes, which induces a stronger immune response than HBsAg, particularly in terms of cytotoxic T lymphocyte (CTL) reaction. In the current study, the HBV PreS2-S gene encoding an extra 26 amino acids (PreS2 C-terminus) located at the N-terminus of HBsAg was cloned into the pVCH1300 expression vector. PreS2-S expressed in the methylotrophic yeast, Hansenula polymorpha, was produced at a yield of up to 250 mg/L. Subsequent purification steps involved hydrophobic adsorption to colloidal silica, ion-exchange chromatography and density ultracentrifugation. The final product was obtained with a total yield of ∼ 15% and purity of ∼ 99%. In keeping with previous studies, ∼ 22 nm viruslike particles were detected using electron microscopy. The generated PreS2-S antigen will be further studied for efficacy and safty in animals.

  8. Postvaccination seroconversion against the surface antigen of Hepatitis B virus, in nursing students

    Directory of Open Access Journals (Sweden)

    Gladys Amanda Mera-Urbano

    2013-09-01

    Full Text Available Objective: To determine the status of seroconversion after vaccination against the surface antigen of hepatitis B virus in nursing students, University of Cauca. Methods: Cross sectional study in students of V and VI semester. The sample was taken from 37 students, 15 of V and 22 of VI semester. The instrument used was a survey that included 11 questions of multiple selections. Records for weight, height and laboratory results were collected; blood samples for antibody titers were performed with informed consent. The data were tabulated and analyzed using SPSS, version 17.0. Results: 89.2% of students had levels of antibodies to the surface antigen. This value was greater than 10 mUI/ml, considered by the scientific community as a protector value of Hepatitis B. 10.8% of had lesser values. Regarding vaccination scheme, 24% had a dose, 19% two, 48% three and 8% had a one dose. The population with 3 doses and reinforcement seroconverted by 100%. Conclusion: This study demonstrated failings in the scheme of vaccination of the students of nursing and that 10.8 % presented lower values than 10 mIU/ml. It is necessary to apply the institutional rules with more strength as a preventive measure for hepatitis B.

  9. Chagasic patients are able to respond against a viral antigen from influenza virus

    Directory of Open Access Journals (Sweden)

    Lasso Paola

    2012-08-01

    Full Text Available Abstract Background Trypanosoma cruzi, the etiological agent of Chagas’ disease, is an obligate intracellular parasite which induces a CD8+ T cell immune response with secretion of cytokines and release of cytotoxic granules. Although an immune-suppressive effect of T. cruzi on the acute phase of the disease has been described, little is known about the capacity of CD8+ T cell from chronic chagasic patients to respond to a non-T. cruzi microbial antigen. Methods In the present paper, the frequency, phenotype and the functional activity of the CD8+ T cells specific from Flu-MP*, an influenza virus epitope, were determined in 13 chagasic patients and 5 healthy donors. Results The results show that Flu-MP* peptide specific CD8+ T cells were found with similar frequencies in both groups. In addition, Flu-MP* specific CD8+ T cells were distributed in the early or intermediate/late differentiation stages without showing enrichment of a specific sub-population. The mentioned Flu-MP* specific CD8+ T cells from chagasic patients were predominately TEM (CCR7- CD62L-, producing IL-2, IFNγ, CD107a/b and perforin, and did not present significant differences when compared with those from healthy donors. Conclusions Our results support the hypothesis that there is no CD8+ T cell nonspecific immune-suppression during chronic Chagas disease infection. Nonetheless, other viral antigens must be studied in order to confirm our findings.

  10. Cowpea mosaic virus-based systems for the expression of antigens and antibodies in plants.

    Science.gov (United States)

    Sainsbury, Frank; Liu, Li; Lomonossoff, George P

    2009-01-01

    This chapter describes the use of Cowpea mosaic virus-based vectors for the production of foreign proteins such as antigens and antibodies in plants. The systems include vectors based on both full-length and deleted versions of RNA-2. In both cases, the modified RNA-2 is replicated by coinoculation with RNA-1. The constructs based on full-length RNA-2 retain the ability to spread systemically throughout an inoculated plant and the infection can be passaged. The vector based on a deleted version of RNA-2 can stably incorporate larger inserts but lacks the ability to move systemically. However, it has the added advantage of biocontainment. In both cases, vector constructs modified to contain a foreign gene of interest can be delivered by agroinfiltration to obtain transient expression of the foreign protein. If required, the same constructs can also be used for stable nuclear transformation. Both types of vector have proved effective for the production in plants of a diverse range of proteins including antigens and antibodies.

  11. Antigen Gene Transfer to Human Plasmacytoid Dendritic Cells Using Recombinant Adenovirus and Vaccinia Virus Vectors

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    Hetty J. Bontkes

    2005-01-01

    Full Text Available Recombinant adenoviruses (RAd and recombinant vaccinia viruses (RVV expressing tumour-associated antigens (TAA are used as anti-tumour vaccines. It is important that these vaccines deliver the TAA to dendritic cells (DC for the induction of a strong immune response. Infection of myeloid DC (MDC with RAd alone is relatively inefficient but CD40 retargeting significantly increases transduction efficiency and DC maturation. Infection with RVV is efficient without DC maturation. Plasmacytoid dendritic cells (PDC play a role in the innate immune response to viral infections through the secretion of IFNα but may also play a role in specific T-cell induction. The aim of our study was to investigate whether PDC are better targets for RAd and RVV based vaccines. RAd alone hardly infected PDC (2% while CD40 retargeting did not improve transduction efficiency, but it did increase PDC maturation (25% CD83 positive cells. Accordingly, specific CTL activation by RAd infected PDC was limited (the number of IFNγ producing CTL was reduced by 75% compared to stimulation with peptide loaded PDC. RVV infected PDC specifically stimulated CTL but PDC were not activated. These Results indicate that PDC are not ideal targets for RAd and RVV based vaccines. However, PDC induced specific CTL activation after pulsing with recombinant protein, indicating that PDC can also cross-present antigens released from surrounding infected cells.

  12. The biased nucleotide composition of the HIV genome: a constant factor in a highly variable virus

    NARCIS (Netherlands)

    van der Kuyl, Antoinette C.; Berkhout, Ben

    2012-01-01

    Viruses often deviate from their hosts in the nucleotide composition of their genomes. The RNA genome of the lentivirus family of retroviruses, including human immunodeficiency virus (HIV), contains e. g. an above average percentage of adenine (A) nucleotides, while being extremely poor in cytosine

  13. Spread of hepatitis C virus among European injection drug users infected with HIV: A phylogenetic analysis

    NARCIS (Netherlands)

    van Asten, Liselotte; Verhaest, Inge; Lamzira, Saida; Hernandez-Aguado, Ildefonso; Zangerle, Robert; Boufassa, Faroudy; Rezza, Giovanni; Broers, Barbara; Robertson, J. Roy; Brettle, Raymond P.; McMenamin, Jim; Prins, Maria; Cochrane, Alexandra; Simmonds, Peter; Coutinho, Roel A.; Bruisten, Sylvia

    2004-01-01

    To describe the spread of hepatitis C virus (HCV) among HCV/human immunodeficiency virus (HIV)-coinfected injection drug users (IDUs), the molecular epidemiology of HCV was studied among 108 IDUs from 7 European countries. Phylogenetic analysis based on the NS5B region showed great sequence

  14. High seroprevalence of human herpes virus 8 (HHV-8 antibodies among vertically HIV-infected pediatric patients living in Germany

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    C Feiterna-Sperling

    2012-11-01

    Full Text Available Background: Human herpes virus 8 (HHV-8, a gamma herpes virus, is the etiological agent for Kaposi sarcoma (KS. HIV-infected adults with advanced immunodeficiency are at risk. Prevalence data of HHV-8 infection in HIV-infected children living in non-endemic areas are limited. Serologic studies indicate low seroprevalence rates of 3–4% for healthy children living in United States and Germany [1]. Purpose of the study: The aim of the study was to determine the seroprevalence of HHV-8 antibodies among vertically HIV-infected pediatric patients in Germany and to evaluate their association with age, gender, ethnicity, and other demographic factors. Methods: In 2012, a multi-center cross-sectional study was conducted in four University Hospitals in Germany. Stored frozen serum specimens obtained from vertically HIV-infected children and adolescents were tested for antibodies against lytic and latent HHV-8 antigens. Data on patients' demographic characteristics and medical history were recorded. Results: A total of 214 HIV-infected children and adolescents (105 males, 109 females were included. The median age was 10.2 years (range 1 months–22.6 years. A high proportion of these children (62% was born in Western Europe, whereas 65% (139/214 of their mothers were born in countries outside Western Europe. The majoritiy (91% of the children had been treated with highly active antiretroviral therapy and 55.2% (116/210 had a HIV-viral load<50 copies/mL. The median CD4 cell count was 1000/L (range 3–4400. The overall seroprevalence of HHV-8 antibodies was 23.8% (51/214. Seroprevalence rates did not show significant differences between age or gender. In the group of young children aged 1 month to 35 months, 19.4% (46/31 had HHV-8 antibodies, compared to 25% (25/100 in children aged 36 months to 11 years, and 24.1% (20/83 children 12 years and older. In the study group, seroprevalence rates were significantly lower in children who were born in Western

  15. Computational analysis of HIV-1 resistance based on gene expression profiles and the virus-host interaction network.

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    Tao Huang

    Full Text Available A very small proportion of people remain negative for HIV infection after repeated HIV-1 viral exposure, which is called HIV-1 resistance. Understanding the mechanism of HIV-1 resistance is important for the development of HIV-1 vaccines and Acquired Immune Deficiency Syndrome (AIDS therapies. In this study, we analyzed the gene expression profiles of CD4+ T cells from HIV-1-resistant individuals and HIV-susceptible individuals. One hundred eighty-five discriminative HIV-1 resistance genes were identified using the Minimum Redundancy-Maximum Relevance (mRMR and Incremental Feature Selection (IFS methods. The virus protein target enrichment analysis of the 185 HIV-1 resistance genes suggested that the HIV-1 protein nef might play an important role in HIV-1 infection. Moreover, we identified 29 infection information exchanger genes from the 185 HIV-1 resistance genes based on a virus-host interaction network analysis. The infection information exchanger genes are located on the shortest paths between virus-targeted proteins and are important for the coordination of virus infection. These proteins may be useful targets for AIDS prevention or therapy, as intervention in these pathways could disrupt communication with virus-targeted proteins and HIV-1 infection.

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

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    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

  17. CD4 lymphocyte counts and serum p24 antigen of no diagnostic value in monitoring HIV-infected patients with pulmonary symptoms

    DEFF Research Database (Denmark)

    Orholm, M; Nielsen, T L; Nielsen, Jens Ole

    1990-01-01

    The diagnostic value of the CD4 cell counts and the HIV p24 antigen were evaluated in a consecutive series of 105 HIV-infected patients experiencing 128 episodes of pulmonary symptoms which required bronchoscopy. One-third of patients with opportunistic infection (OI) had CD4 counts greater than 0....... In conclusion, the CD4 cell counts and the presence of p24 antigen in serum had a very limited predictive value for the presence of OI in HIV-infected patients with pulmonary symptoms....

  18. PENGAMATAN SERO—VIROLOGI BEBERAPA JENIS ANTIGEN VIRUS PADA SERUM TALIPUSAT BAYI DI RS. CIPTO MANGUNKUSUMO, JAKARTA

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    Djoko Yuwono

    2012-09-01

    Full Text Available Perinatal infection due to viral agents from mother to neonate is still a major cause of viral transmis­sion in developing countries. Several type of viruses which are known to be transmitted vertieally or perinatally from mother to neonates are: Hepatitis B virus, Herpes simplex, Rubella and Cytomegalovi­rus. In attempt to estimate the real problem of viral diseases which are vertically or perinatally transmis­sible among infants, a survey on sero-virology of several type viral antigens among neonates who were borned in Dr. Cipto Mangunkusumo hospital, was carried out. A total of 227 blood samples of umbillical cord were examined for the presence of their viral anti­gens such as: Hepatitis B surface antigen (HBsAg, Herpes simplex type 1 and type 2, and anti-rubella IgM as an indicator of early infection due to rubella virus in the fetus. The detection of antigens and anti-rubella IgM in the serum.were done by ELISA methode using reagents which are commercially available. The result of the study indicated that there was a possibility of perinatal infection due to related viruses, i.e.: 2.2%; 1.9% and 14.3% due to HBsAg; Herpes simplex type 1 and type 2 respectivelly, however none of the serum indicated seropositive IgM against rubella virus: infection.

  19. Human immunodeficiency virus (HIV) inactivation of banked bone by gamma irradiation.

    Science.gov (United States)

    Salai, M; Vonsover, A; Pritch, M; von Versen, R; Horoszowski, H

    1997-01-01

    The increasing number of patients with acquired immunodeficiency syndrome (AIDS) and human immunodeficiency virus(HIV)-positive carriers, poses difficulties when musculo-skeletal tissues are considered for banking in readiness for future clinical application. This study was conducted to test the actual yield of gamma irradiation on HIV infectivity, within HIV-infected bones. The effect of gamma irradiation on bones containing T-cells chronically infected with HIV type I (HIV-I) was studied, in respect to inactivation of the virus. After exposure of the cell-free virus or infected T-cells to 2.5 megarads of gamma irradiation, the authors were able to demonstrate complete inactivation of the virus. It would appear from this study that gamma irradiation at this dose is sufficient to achieve clinical sterilisation of bones and facilitate their use for reconstructive procedures by eliminating the risk of HIV transmission to the recipient. Furthermore, when preparing bones for banking, this would also seem to be the method of choice in preventing the transmission of various strains of bacteria, fungi and other viruses.

  20. Supraphysiologic control over HIV-1 replication mediated by CD8 T cells expressing a re-engineered CD4-based chimeric antigen receptor.

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    Rachel S Leibman

    2017-10-01

    Full Text Available HIV is adept at avoiding naturally generated T cell responses; therefore, there is a need to develop HIV-specific T cells with greater potency for use in HIV cure strategies. Starting with a CD4-based chimeric antigen receptor (CAR that was previously used without toxicity in clinical trials, we optimized the vector backbone, promoter, HIV targeting moiety, and transmembrane and signaling domains to determine which components augmented the ability of T cells to control HIV replication. This re-engineered CAR was at least 50-fold more potent in vitro at controlling HIV replication than the original CD4 CAR, or a TCR-based approach, and substantially better than broadly neutralizing antibody-based CARs. A humanized mouse model of HIV infection demonstrated that T cells expressing optimized CARs were superior at expanding in response to antigen, protecting CD4 T cells from infection, and reducing viral loads compared to T cells expressing the original, clinical trial CAR. Moreover, in a humanized mouse model of HIV treatment, CD4 CAR T cells containing the 4-1BB costimulatory domain controlled HIV spread after ART removal better than analogous CAR T cells containing the CD28 costimulatory domain. Together, these data indicate that potent HIV-specific T cells can be generated using improved CAR design and that CAR T cells could be important components of an HIV cure strategy.

  1. Sero – prevalence of Human Immunodeficency Virus (HIV) infection ...

    African Journals Online (AJOL)

    A total of 281 samples were tested serologically by the serial algorithm method using three standard kits namely Abbott Determine HIV1/2, the Chembio HIV1/2 STATPAK assay and the Trinity Biotech UniGold HIV tests. Results indicated that 24(12.1%) were infected with HIV. The percentage prevalence by educational ...

  2. GB Virus C Proteine interferieren mit der Replikation von HIV-1

    OpenAIRE

    Jung, Susan

    2010-01-01

    GB Virus C (GBV-C) was discovered in 1995 within the search for new hepatitis viruses. The human apathogenic enveloped RNA virus belongs to the family of the Flaviviridae and replicates primarily in lymphocytes. Transmission occurs mainly by sexual or parenteral exposure. In developed countries up to 6% of the healthy population and up to 40% of multiply exposed individuals, such as HIV patients, are viremic for GBV-C. Since the late 1990s, GBV-C has been investigated in the context of HIV. U...

  3. Atomic resolution structural characterization of recognition of histo-blood group antigens by Norwalk virus

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jae-Mun; Hutson, Anne M.; Estes, Mary K.; Prasad, B.V. Venkataram (Baylor)

    2008-07-28

    Members of Norovirus, a genus in the family Caliciviridae, are causative agents of epidemic diarrhea in humans. Susceptibility to several noroviruses is linked to human histo-blood type, and its determinant histo-blood group antigens (HBGAs) are regarded as receptors for these viruses. Specificity for these carbohydrates is strain-dependent. Norwalk virus (NV) is the prototype genogroup I norovirus that specifically recognizes A- and H-type HBGA, in contrast to genogroup II noroviruses that exhibit a more diverse HBGA binding pattern. To understand the structural basis for how HBGAs interact with the NV capsid protein, and how the specificity is achieved, we carried out x-ray crystallographic analysis of the capsid protein domain by itself and in complex with A- and H-type HBGA at a resolution of {approx}1.4 {angstrom}. Despite differences in their carbohydrate sequence and linkage, both HBGAs bind to the same surface-exposed site in the capsid protein and project outward from the capsid surface, substantiating their possible role in initiating cell attachment. Precisely juxtaposed polar side chains that engage the sugar hydroxyls in a cooperative hydrogen bonding and a His/Trp pair involved in a cation-p interaction contribute to selective and specific recognition of A- and H-type HBGAs. This unique binding epitope, confirmed by mutational analysis, is highly conserved, but only in the genogroup I noroviruses, suggesting that a mechanism by which noroviruses infect broader human populations is by evolving different sites with altered HBGA specificities.

  4. Selective susceptibility of human skin antigen presenting cells to productive dengue virus infection.

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    Daniela Cerny

    2014-12-01

    Full Text Available Dengue is a growing global concern with 390 million people infected each year. Dengue virus (DENV is transmitted by mosquitoes, thus host cells in the skin are the first point of contact with the virus. Human skin contains several populations of antigen-presenting cells which could drive the immune response to DENV in vivo: epidermal Langerhans cells (LCs, three populations of dermal dendritic cells (DCs, and macrophages. Using samples of normal human skin we detected productive infection of CD14(+ and CD1c(+ DCs, LCs and dermal macrophages, which was independent of DC-SIGN expression. LCs produced the highest viral titers and were less sensitive to IFN-β. Nanostring gene expression data showed significant up-regulation of IFN-β, STAT-1 and CCL5 upon viral exposure in susceptible DC populations. In mice infected intra-dermally with DENV we detected parallel populations of infected DCs originating from the dermis and migrating to the skin-draining lymph nodes. Therefore dermal DCs may simultaneously facilitate systemic spread of DENV and initiate the adaptive anti-viral immune response.

  5. Plant virus particles carrying tumour antigen activate TLR7 and Induce high levels of protective antibody.

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    Jantipa Jobsri

    Full Text Available Induction of potent antibody is the goal of many vaccines targeted against infections or cancer. Modern vaccine designs that use virus-like particles (VLP have shown efficacy for prophylactic vaccination against virus-associated cancer in the clinic. Here we used plant viral particles (PVP, which are structurally analogous to VLP, coupled to a weak idiotypic (Id tumour antigen, as a conjugate vaccine to induce antibody against a murine B-cell malignancy. The Id-PVP vaccine incorporates a natural adjuvant, the viral ssRNA, which acts via TLR7. It induced potent protective anti-Id antibody responses in an in vivo mouse model, superior to the "gold standard" Id vaccine, with prevalence of the IgG2a isotype. Combination with alum further increased antibody levels and maintained the IgG2a bias. Engagement of TLR7 in vivo was followed by secretion of IFN-α by plasmacytoid dendritic cells and by activation of splenic CD11chi conventional dendritic cells. The latter was apparent from up-regulation of co-stimulatory molecules and from secretion of a wide range of inflammatory cytokines and chemokines including the Th1-governing cytokine IL-12, in keeping with the IgG2a antibody isotype distribution. PVP conjugates are a novel cancer vaccine design, offering an attractive molecular form, similar to VLP, and providing T-cell help. In contrast to VLP, they also incorporate a safe "in-built" ssRNA adjuvant.

  6. Occult hepatitis B virus coinfection in HIV-positive African migrants to the UK: a point prevalence study.

    Science.gov (United States)

    Chadwick, D; Doyle, T; Ellis, S; Price, D; Abbas, I; Valappil, M; Geretti, A M

    2014-03-01

    Occult (surface antigen-negative/DNA-positive) hepatitis B virus (HBV) infection is common in areas of the world where HBV is endemic. The main objectives of this study were to determine the prevalence of occult HBV infection in HIV-infected African migrants to the UK and to determine factors associated with occult coinfection. This anonymized point-prevalence study identified Africans attending three HIV clinics, focussing on patients naïve to antiretroviral therapy (ART). Stored blood samples were tested for HBV DNA. Prevalence was calculated in the entire cohort, as well as in subpopulations. Risk factors for occult HBV coinfection were identified using logistic regression analysis. Among 335 HIV-positive African migrants, the prevalence of occult HBV coinfection was 4.5% [95% confidence interval (CI) 2.8-7.4%] overall, and 6.5% (95% CI 3.9-10.6%) and 0.8% (95% CI 0.2-4.6%) in ART-naïve and ART-experienced patients, respectively. Among ART-naïve anti-HBV core (anti-HBc)-positive patients, the prevalence was 16.4% (95% CI 8.3-25.6%). The strongest predictor of occult coinfection was anti-HBc positivity [odds ratio (OR) 7.4; 95% CI 2.0-27.6]. Median HBV DNA and ALT levels were 54 IU/mL [interquartile range (IQR) 33-513 IU/mL] and 22 U/L (IQR 13-27 U/L), respectively. Occult HBV coinfection remains under-diagnosed in African HIV-infected patients in the UK. Given the range of HBV DNA levels observed, further studies are warranted to determine its clinical significance and to guide screening strategies and ART selection in these patients. © 2013 British HIV Association.

  7. A competitive ELISA for detection of antibodies to the group antigen of bluetongue virus.

    Science.gov (United States)

    Reddington, J J; Reddington, G M; MacLachlan, N J

    1991-04-01

    A competitive enzyme-linked immunosorbent assay (cELISA) was developed to detect antibodies to the group antigen of bluetongue virus (BTV). The epitope recognized by the BTV-specific monoclonal antibody was confirmed, by immunofluorescence staining of monolayers of virus-infected Vero cells, to be present on BTV serotypes 2, 10, 11, 13, and 17 but not on epizootic hemorrhagic disease virus (EHDV) serotypes 1 and 2. Sera from BTV-inoculated ruminants and rabbits were used to evaluate the cELISA and to compare its specificity and sensitivity with that of the conventional BTV-specific agar gel immunodiffusion (AGID) and serum neutralization (SN) tests. Rabbit antisera to the 5 serotypes of BTV present in the United States had cELISA titers (inverse of the final dilution of serum that gave greater than 20% inhibition) that ranged from 32 to greater than 1.024. Seroconversion of the 8 calves and lambs inoculated with BTV was detected by all 3 serologic tests (SN, AGID, cELISA) by 6 weeks after inoculation. Specificity of the cELISA test was confirmed with bovine sera that contained neutralizing antibodies to EHDV but not to the 5 serotypes of BTV present in the United States; these sera gave positive results by AGID test but were negative by cELISA. The sensitivity and specificity of the cELISA test was further confirmed by analysis of a panel of bovine test sera supplied by the National Veterinary Services Laboratories, indicating that the cELISA is a superior test for detection of BTV group-specific antibodies in sera from ruminants in the United States.

  8. Stability of Bovine viral diarrhea virus antigen in ear punch samples collected from bovine fetuses.

    Science.gov (United States)

    Ridpath, Julia F; Chiang, Yu-Wei; Waldbillig, Jill; Neill, John D

    2009-05-01

    Fourteen first-calf heifers were tested free of antibodies against Bovine viral diarrhea viruses (BVDV) by serum neutralization and free of BVDV by polymerase chain reaction. Twelve were exposed to BVDV-1b strain CA0401186a at 84-86 days of gestation, and 2 were exposed to mock inoculum and served as negative controls. Fetuses were harvested by cesarean section at 115-117 days of gestation. The 12 fetuses removed from the BVDV-exposed heifers were BVDV positive based on virus isolation from kidney, thymus, cerebellum, and spleen. It can be assumed that these fetuses would have developed into persistently infected calves had they been allowed to go to term. Virus was not isolated from the fetuses of control animals. Ear punch samples were collected from all fetuses at time of harvest. Antigen capture enzyme-linked immunosorbent assay (ACE), using a commercial kit, was performed on ear punch samples that were frozen within 5 hr of collection and stored at -20 degrees C until tested, tested after storage for 7 days at room temperature (18-25 degrees C), or tested after storage for 7 days at 37 degrees C. Samples stored for 7 days at room temperature or 37 degrees C lost an average of 34% of their starting weight. All samples from BVDV isolation-positive fetuses tested positive by ACE, whereas samples from nonexposed fetuses tested negative, regardless of storage conditions. These results suggest that ACE testing of skin samples collected from aborted fetuses and stillborn calves found in the field may represent a practical surveillance method for BVDV-induced reproductive disease.

  9. Novel 6xHis tagged foot-and-mouth disease virus vaccine bound to nanolipoprotein adjuvant via metal ions provides antigenic distinction and effective protective immunity

    Science.gov (United States)

    Here, we engineered two FMD viruses and histidine residues inserted into or fused to the FMDV capsid. Both 6xHis viruses exhibited growth kinetics, plaque morphologies and antigenic characteristics similar to wild-type virus. The 6xHis tag allowed one-step purification of the mutant virions by Co2...

  10. Hepatitis B Virus DNA in Blood Samples Positive for Antibodies to Core Antigen and Negative for Surface Antigen

    Science.gov (United States)

    Gutiérrez, C.; León, G.; Loureiro, C. L.; Uzcátegui, N.; Liprandi, F.; Pujol, F. H.

    1999-01-01

    Anti-hepatitis B core antigen (HBcAg)-positive hepatitis B surface antigen (HBsAg)-negative plasma samples from blood donors were tested by nested PCR. DNA positivity was more significantly associated with high levels of anti-HBcAg than with low levels of anti-HBsAg antibodies. Analysis of a dilution of anti-HBcAg antibodies might result in a more rational exclusion of anti-HBcAg-positive HBsAg-negative samples, reducing the number of donations discarded and enabling more countries to incorporate anti-HBcAg testing. PMID:10473534

  11. Immunological changes in human immunodeficiency virus (HIV)-infected individuals during HIV-specific protease inhibitor treatment

    DEFF Research Database (Denmark)

    Ullum, H; Katzenstein, T; Aladdin, H

    1999-01-01

    Vaccinia virus was increased after 3-6 months, whereas the specific HIV-directed CTL activity and the concentration and lytic activity of natural killer (NK) cells were unchanged during follow-up. These results demonstrate that the initiation of a treatment including an HIV protease inhibitor is followed......The present study examines the influence of effective anti-retroviral treatment on immune function, evaluated by a broad array of immunological tests. We followed 12 individuals infected with human immunodeficiency virus (HIV) for 6 months after initiation of combination anti-retroviral treatment...... including a protease inhibitor. Unstimulated and pokeweed mitogen (PWM)-, interleukin (IL)-2- and phytohaemagglutinin (PHA)-stimulated lymphocyte proliferative responses increased during follow-up reaching average levels from 1.3-fold (PHA) to 3.7-fold (PWM) above baseline values. The total CD4+ lymphocyte...

  12. Increased incidence of cancer observed in HIV/hepatitis C virus-coinfected patients versus HIV-monoinfected.

    Science.gov (United States)

    Meijide, Héctor; Pértega, Sonia; Rodríguez-Osorio, Iria; Castro-Iglesias, Ángeles; Baliñas, Josefa; Rodríguez-Martínez, Guillermo; Mena, Álvaro; Poveda, Eva

    2017-05-15

    Cancer is a growing problem in persons living with HIV infection (PLWH) and hepatitis C virus (HCV) coinfection could play an additional role in carcinogenesis. Herein, all cancers in an HIV-mono and HIV/HCV-coinfected cohort were evaluated and compared to identify any differences between these two populations. A retrospective cohort study was conducted including all cancers in PLWH between 1993 and 2014. Cancers were classified in two groups: AIDS-defining cancer (ADC) and non-AIDS-defining cancer (NADC). Cancer incidence rates were calculated and compared with that observed in the Spanish general population (GLOBOCAN, 2012), computing the standardized incidence ratios (SIRs). A competing risk approach was used to estimate the probability of cancer after HIV diagnosis. Cumulative incidence in HIV-monoinfected and HIV/HCV-coinfected patients was also compared using multivariable analysis. A total of 185 patients (117 HIV-monoinfected and 68 HIV/HCV) developed cancer in the 26 580 patient-years cohort, with an incidence rate of 696 cancers per 100 000 person-years, higher than in the general population (SIR = 3.8). The incidence rate of NADC in HIV/HCV-coinfected patients was 415.0 (SIR = 3.4), significantly higher than in monoinfected (377.3; SIR = 1.8). After adjustments, HIV/HCV-coinfected patients had a higher cumulative incidence of NADC than HIV-monoinfected (adjusted hazard ratio = 1.80), even when excluding hepatocellular carcinomas (adjusted hazard ratio = 1.26). PLWH have a higher incidence of NADC than the general population and HCV-coinfection is associated with a higher incidence of NADC. These data justify the need for prevention strategies in these two populations and the importance of eradicating HCV.

  13. Amino Acid Changes in the HIV-1 gp41 Membrane Proximal Region Control Virus Neutralization Sensitivity

    Directory of Open Access Journals (Sweden)

    Todd Bradley

    2016-10-01

    Full Text Available Most HIV-1 vaccines elicit neutralizing antibodies that are active against highly sensitive (tier-1 viruses or rare cases of vaccine-matched neutralization-resistant (tier-2 viruses, but no vaccine has induced antibodies that can broadly neutralize heterologous tier-2 viruses. In this study, we isolated antibodies from an HIV-1-infected individual that targeted the gp41 membrane-proximal external region (MPER that may have selected single-residue changes in viral variants in the MPER that resulted in neutralization sensitivity to antibodies targeting distal epitopes on the HIV-1 Env. Similarly, a single change in the MPER in a second virus from another infected-individual also conferred enhanced neutralization sensitivity. These gp41 single-residue changes thus transformed tier-2 viruses into tier-1 viruses that were sensitive to vaccine-elicited tier-1 neutralizing antibodies. These data demonstrate that Env amino acid changes within the MPER bnAb epitope of naturally-selected escape viruses can increase neutralization sensitivity to multiple types of neutralizing antibodies, and underscore the critical importance of the MPER for maintaining the integrity of the tier-2 HIV-1 trimer.

  14. The exonuclease domain of Lassa virus nucleoprotein is involved in antigen-presenting-cell-mediated NK cell responses.

    Science.gov (United States)

    Russier, Marion; Reynard, Stéphanie; Carnec, Xavier; Baize, Sylvain

    2014-12-01

    Lassa virus is an Old World Arenavirus which causes Lassa hemorrhagic fever in humans, mostly in West Africa. Lassa fever is an important public health problem, and a safe and effective vaccine is urgently needed. The infection causes immunosuppression, probably due to the absence of activation of antigen-presenting cells (dendritic cells and macrophages), low type I interferon (IFN) production, and deficient NK cell function. However, a recombinant Lassa virus carrying D389A and G392A substitutions in the nucleoprotein that abolish the exonuclease activity and IFN activation loses its inhibitory activity and induces strong type I IFN production by dendritic cells and macrophages. We show here that during infection by this mutant Lassa virus, antigen-presenting cells trigger efficient human NK cell responses in vitro, including production of IFN-γ and cytotoxicity. NK cell activation involves close contact with both antigen-presenting cells and soluble factors. We report that infected dendritic cells and macrophages express the NKG2D ligands major histocompatibility complex (MHC) class I-related chains A and B and that they may produce interleukin-12 (IL-12), IL-15, and IL-18, all involved in NK cell functions. NK cell degranulation is significantly increased in cocultures, suggesting that NK cells seem to kill infected dendritic cells and macrophages. This work confirms the inhibitory function of Lassa virus nucleoprotein. Importantly, we demonstrate for the first time that Lassa virus nucleoprotein is involved in the inhibition of antigen-presenting cell-mediated NK cell responses. The pathogenesis and immune responses induced by Lassa virus are poorly known. Recently, an exonuclease domain contained in the viral nucleoprotein has been shown to be able to inhibit the type I IFN response by avoiding the recognition of viral RNA by cell sensors. Here, we studied the responses of NK cells to dendritic cells and macrophages infected with a recombinant Lassa virus in

  15. Targeting cell surface HIV-1 Env protein to suppress infectious virus formation

    Science.gov (United States)

    Bastian, Arangassery Rosemary; Ang, Charles G.; Kamanna, Kantharaju; Shaheen, Farida; Huang, Yu-Hung; McFadden, Karyn; Duffy, Caitlin; Bailey, Lauren D.; Sundaram, Ramalingam Venkat Kalyana; Chaiken, Irwin

    2017-01-01

    HIV-1 Env protein is essential for host cell entry, and targeting Env remains an important antiretroviral strategy. We previously found that a peptide triazole thiol KR13 and its gold nanoparticle conjugate AuNP-KR13 directly and irreversibly inactivate the virus by targeting the Env protein, leading to virus gp120 shedding, membrane disruption and p24 capsid protein release. Here, we examined the consequences of targeting cell-surface Env with the virus inactivators. We found that both agents led to formation of non-infectious virus from transiently transfected 293T cells. The budded non-infectious viruses lacked Env gp120 but contained gp41. Importantly, budded virions also retained the capsid protein p24, in stark contrast to p24 leakage from viruses directly treated by these agents and arguing that the agents led to deformed viruses by transforming the cells at a stage before virus budding. We found that the Env inactivators caused gp120 shedding from the transiently transfected 293T cells as well as non-producer CHO-K1-gp160 cells. Additionally, AuNP-KR13 was cytotoxic against the virus-producing 293T and CHO-K1-gp160 cells, but not untransfected 293T or unmodified CHO-K1 cells. The results obtained reinforce the argument that cell-surface HIV-1 Env is metastable, as on virus particles, and provides a conformationally vulnerable target for virus suppression and infectious cell inactivation. PMID:28390972

  16. Cross-reactive antigenicity of nucleoproteins of lyssaviruses recognized by a monospecific antirabies virus nucleoprotein antiserum on paraffin sections of formalin-fixed tissues.

    Science.gov (United States)

    Inoue, Satoshi; Sato, Yuko; Hasegawa, Hideki; Noguchi, Akira; Yamada, Akio; Kurata, Takeshi; Iwasaki, Takuya

    2003-08-01

    Diagnosis of rabies is routinely confirmed by detection of rabies virus antigens in acetone-fixed frozen brain tissues or imprint smears using an immunofluorescence method with commercial antirabies virus antibodies. Since recent molecular analyses disclosed wide heterogeneity in the genome sequences of rabies virus strains and related lyssaviruses, it is necessary to confirm the presence of common epitopes in these lyssaviruses. In this study we confirmed the presence of cross-reactive antigens of various lyssaviruses in paraffin sections of formalin-fixed tissue using a monospecific rabbit antiserum prepared by immunization with a recombinant nucleoprotein of rabies virus. By immunohistochemical application, the antigen was detected predominantly in the cytoplasm of neurons in the brains of mice infected with rabies virus, Duvenhage virus, Mokola virus and European bat lyssavirus-1, while no cross-reaction was observed in uninfected humans and animals including dogs, bats, and raccoons. In addition, we examined one autopsy case that was infected in a rabies-endemic nation and developed the clinical manifestation of rabies after returning to Japan in 1970, and found that the antigen was well preserved in paraffin sections of formalin-fixed tissues. Thus, this suggests that the lyssavirus-specific antigen is recognized by the monospecific antibody against rabies virus nucleoprotein, and that this cross-reactive antigen is detectable on formalin-fixed paraffin-embedded tissues by immunohistochemical analysis.

  17. MERS-CoV and H5N1 influenza virus antagonize antigen presentation by altering the epigenetic landscape

    Energy Technology Data Exchange (ETDEWEB)

    Menachery, Vineet D.; Schäfer, Alexandra; Burnum-Johnson, Kristin E.; Mitchell, Hugh D.; Eisfeld, Amie J.; Walters, Kevin B.; Nicora, Carrie D.; Purvine, Samuel O.; Casey, Cameron P.; Monroe, Matthew E.; Weitz, Karl K.; Stratton, Kelly G.; Webb-Robertson, Bobbie-Jo M.; Gralinski, Lisa E.; Metz, Thomas O.; Smith, Richard D.; Waters, Katrina M.; Sims, Amy C.; Kawaoka, Yoshihiro; Baric, Ralph S.

    2018-01-16

    Convergent evolution dictates that diverse groups of viruses will target both similar and distinct host pathways in order to manipulate the immune response and improve infection. In this study, we sought to leverage this uneven viral antagonism to identify critical host factors that govern disease outcome. Utilizing a systems based approach, we examined differential regulation of IFNγ dependent genes following infection with highly pathogenic viruses including influenza (H5N1-VN1203, H1N1-CA04) and coronaviruses (SARS-CoV, MERS-CoV). Categorizing by function, we observed down regulation of genes associated with antigen presentation following both H5N1-VN1203 and MERS-CoV infection. Further examination revealed global down regulation of antigen presentation genes and was confirmed by proteomics for both H5N1-VN1203 and MERS-CoV infection. Importantly, epigenetic analysis suggested that DNA methylation rather than histone modification plays a crucial role in MERS-CoV mediated antagonism of antigen presentation genes; in contrast, H5N1-VN1203 likely utilizes a combination of epigenetic mechanisms to target antigen presentation. Together, the results indicate a common approach utilized by H5N1-VN1203 and MERS-CoV to modulate antigen presentation and the host adaptive immune response.

  18. Detection of Hepatitis B Virus Antigens in Paraffin-embedded Liver Specimens from the Amazon Region, Brazil

    Directory of Open Access Journals (Sweden)

    Simonetti SRR

    2002-01-01

    Full Text Available Hepatic viscerotomy of paraffin-preserved old specimens, collected in the period from 1934 to 1967, were analyzed by immunohistochemical assays to detect hepatitis B, hepatitis D, dengue and yellow fever virus antigens. The material belongs to the Yellow Fever Collection, Department of Pathology, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil and the cases were diagnosed at that time according to clinical aspects and histopathological findings reporting viral hepatitis, yellow fever, focal necrosis and hepatic atrophy. From the 79 specimens, 69 were collected at the Labrea Region and the other 10 in different other localities in the Amazon Region. The five micra thick histological slices were analyzed for the presence of hepatitis B surface antigen (HBsAg and hepatitis B core antigen (HBcAg by immunoperoxidase technique. An immunofluorescence assay was applied to the detection of hepatitis D, yellow fever and dengue virus antigens. Nine (11.4% histological samples were HBsAg reactive and 5 (6.3% were HBcAg reactive. The oldest reactive sample was from 1934. Viral antigens related to the other pathologies were not detected in this study. Our results confirm that the methodology described may be used to elucidate the aetiology of hepatitis diseases even after a long time of conservation of the specimens.

  19. Molecular aspects of antibody-antigen interactions : size reduction of a herpes simplex virus neutralizing antibody and its antigen

    NARCIS (Netherlands)

    Schellekens, Gerardus Antonius

    1996-01-01

    Antibody molecules, produced as a response against foreign substances, interact with their antigen in a very specific manner. Antibodies with a predetermined specificity (monoclonal antibodies) can be produced and are widely used in medicine and science as indicator molecules. Genetic engineering of

  20. Synthetic peptides define the fine specificity of the human immunodeficiency virus (HIV) gp160 humoral immune response in HIV type 1-infected chimpanzees.

    OpenAIRE

    Warren, R Q; Wolf, H; Shuler, K R; Eichberg, J W; Zajac, R A; Boswell, R N; Kanda, P; Kennedy, R C

    1990-01-01

    The fine specificities of antibodies produced against human immunodeficiency virus type 1 (HIV-1) gp160 were examined in sera from 23 HIV-1-infected chimpanzees. These animals had been infected with one of six isolates of HIV-1. Sera were screened by enzyme-linked immunosorbent assay for reactivity against seven synthetic peptides corresponding to regions of gp160. Chimpanzees appear to remain healthy after infection with HIV-1, suggesting that these animals may prevent extensive spread of th...

  1. Design and application of GB virus C (GBV-C) peptide microarrays for diagnosis of GBV-C/HIV-1 co-infection.

    Science.gov (United States)

    Fernández, Leticia; Bleda, M José; Gómara, M José; Haro, Isabel

    2013-05-01

    The main objectives of the design of GB virus C (GBV-C) peptide microarrays are the miniaturisation of antigen-antibody interaction assays, the simultaneous analysis of several peptide sequences and the reduction in the volume of serum required from patients since this always represents a limiting factor in studies to develop new systems for diagnosing human diseases. We herein report the design of a microarray immunoassay based on synthetic peptides derived from the GBV-C E2 protein to evaluate their diagnostic value in detecting anti-E2 antibodies in HIV-1 patients. To this end, peptide microarrays were initially prepared to identify the most relevant epitopes in the GBV-C E2 protein. Thus, 124 peptides composed of 18 amino acids covering the whole E2-protein sequence, with 15 residue overlaps, were spotted in triplicate onto γ-aminopropyl silane-functionalised adsorbent binding slides. The procedure to select the E2 protein epitopes was carried out using serum samples from HIV-1-infected patients. The samples had previously been tested for the presence or absence of GBV-C anti-E2 antibodies by means of the Abbott test. Thus, 11 specific epitopes in the GBV-C E2 protein were identified. Subsequently, peptide antigen microarrays were constructed using the E2 epitopes identified to detect GBV-C anti-E2 antibodies in the serum of HIV-1-infected patients with no known GBV-C co-infection. The 11 peptides selected identified anti-E2 GBV-C antibodies among HIV-1-infected patients, and a reactivity of 47 % was established. The potential antigenic peptides selected could be considered a useful tool for designing a new diagnostic system based on peptide microarrays to determine anti-GBV-C E2 antibodies in the serum of HIV-1-infected patients.

  2. Modeling virus capsids and their protein binding -- the search for weak regions within the HIV capsid

    Science.gov (United States)

    Sankey, Otto F.; Benson, Daryn E.; Gilbert, C. Michael

    2011-03-01

    Viruses remain a threat to the health of humans worldwide with 33 million infected with HIV. Viruses are ubiquitous, infecting animals, plants, and bacteria. Each virus infects in its own unique manner making the problem seem intractable. However, some general physical steps apply to many viruses and the application of basic physical modeling can potentially have great impact. The aim of this theoretical study is to investigate the stability of the HIV viral capsid (protein shell). The structural shell can be compromised by physical probes such as pulsed laser light [1,2]. But, what are the weakest regions of the capsid so that we can begin to understand vulnerabilities of these deadly materials? The atomic structure of HIV capsids is not precisely known and we begin by describing our work to model the capsid structure. We have constructed three representative viral capsids of different CA protein number -- HIV-900, HIV-1260 and HIV-1740. The complexity of the assembly requires a course grained model to investigate protein interactions within the capsid which we will describe.

  3. Infection with Hepatitis C Virus among HIV-Infected Pregnant Women in Thailand

    Directory of Open Access Journals (Sweden)

    Denise J. Jamieson

    2008-01-01

    Full Text Available Objective. The purpose of this study was to describe the epidemiology of coinfection with hepatitis C virus (HCV and HIV among a cohort of pregnant Thai women. Methods. Samples from 1771 pregnant women enrolled in three vertical transmission of HIV studies in Bangkok, Thailand, were tested for HCV. Results. Among HIV-infected pregnant women, HCV seroprevelance was 3.8% and the active HCV infection rate was 3.0%. Among HIV-uninfected pregnant women, 0.3% were HCV-infected. Intravenous drug use by the woman was the factor most strongly associated with HCV seropositivity. Among 48 infants tested for HCV who were born to HIV/HCV coinfected women, two infants were HCV infected for an HCV transmission rate of 4.2% (95% 0.51–14.25%. Conclusions. HCV seroprevalence and perinatal transmission rates were low among this Thai cohort of HIV-infected pregnant women.

  4. Identifying potential survival strategies of HIV-1 through virus-host protein interaction networks

    Directory of Open Access Journals (Sweden)

    Boucher Charles AB

    2010-07-01

    Full Text Available Abstract Background The National Institute of Allergy and Infectious Diseases has launched the HIV-1 Human Protein Interaction Database in an effort to catalogue all published interactions between HIV-1 and human proteins. In order to systematically investigate these interactions functionally and dynamically, we have constructed an HIV-1 human protein interaction network. This network was analyzed for important proteins and processes that are specific for the HIV life-cycle. In order to expose viral strategies, network motif analysis was carried out showing reoccurring patterns in virus-host dynamics. Results Our analyses show that human proteins interacting with HIV form a densely connected and central sub-network within the total human protein interaction network. The evaluation of this sub-network for connectivity and centrality resulted in a set of proteins essential for the HIV life-cycle. Remarkably, we were able to associate proteins involved in RNA polymerase II transcription with hubs and proteasome formation with bottlenecks. Inferred network motifs show significant over-representation of positive and negative feedback patterns between virus and host. Strikingly, such patterns have never been reported in combined virus-host systems. Conclusions HIV infection results in a reprioritization of cellular processes reflected by an increase in the relative importance of transcriptional machinery and proteasome formation. We conclude that during the evolution of HIV, some patterns of interaction have been selected for resulting in a system where virus proteins preferably interact with central human proteins for direct control and with proteasomal proteins for indirect control over the cellular processes. Finally, the patterns described by network motifs illustrate how virus and host interact with one another.

  5. High sensitivity detection and sorting of infectious human immunodeficiency virus (HIV-1) particles by flow virometry.

    Science.gov (United States)

    Bonar, Michał M; Tilton, John C

    2017-05-01

    Detection of viruses by flow cytometry is complicated by their small size. Here, we characterized the ability of a standard (FACSAria II) and a sub-micron flow cytometer (A50 Micro) to resolve HIV-1 viruses. The A50 was superior at resolving small particles but did not reliably distinguish HIV-1, extracellular vesicles, and laser noise by light scatter properties alone. However, single fluorescent HIV-1 particles could readily be detected by both cytometers. Fluorescent particles were sorted and retained infectivity, permitting further exploration of the functional consequences of HIV-1 heterogeneity. Finally, flow cytometry had a limit of detection of 80 viruses/ml, nearly equal to PCR assays. These studies demonstrate the power of flow cytometry to detect and sort viral particles and provide a critical toolkit to validate methods to label wild-type HIV-1; quantitatively assess integrity and aggregation of viruses and virus-based therapeutics; and efficiently screen drugs inhibiting viral assembly and release. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Fullerene Derivatives Strongly Inhibit HIV-1 Replication by Affecting Virus Maturation without Impairing Protease Activity

    Science.gov (United States)

    Martinez, Zachary S.; Castro, Edison; Seong, Chang-Soo; Cerón, Maira R.

    2016-01-01

    Three compounds (1, 2, and 3) previously reported to inhibit HIV-1 replication and/or in vitro activity of reverse transcriptase were studied, but only fullerene derivatives 1 and 2 showed strong antiviral activity on the replication of HIV-1 in human CD4+ T cells. However, these compounds did not inhibit infection by single-round infection vesicular stomatitis virus glycoprotein G (VSV-G)-pseudotyped viruses, indicating no effect on the early steps of the viral life cycle. In contrast, analysis of single-round infection VSV-G-pseudotyped HIV-1 produced in the presence of compound 1 or 2 showed a complete lack of infectivity in human CD4+ T cells, suggesting that the late stages of the HIV-1 life cycle were affected. Quantification of virion-associated viral RNA and p24 indicates that RNA packaging and viral production were unremarkable in these viruses. However, Gag and Gag-Pol processing was affected, as evidenced by immunoblot analysis with an anti-p24 antibody and the measurement of virion-associated reverse transcriptase activity, ratifying the effect of the fullerene derivatives on virion maturation of the HIV-1 life cycle. Surprisingly, fullerenes 1 and 2 did not inhibit HIV-1 protease in an in vitro assay at the doses that potently blocked viral infectivity, suggesting a protease-independent mechanism of action. Highlighting the potential therapeutic relevance of fullerene derivatives, these compounds block infection by HIV-1 resistant to protease and maturation inhibitors. PMID:27431232

  7. Molecular characterization of viruses associated with gastrointestinal infection in HIV-positive patients

    Directory of Open Access Journals (Sweden)

    Raquel C Silva

    Full Text Available BACKGROUND: Diarrhea is a major cause of morbidity and mortality among HIV-infected patients worldwide. OBJECTIVE: We sought to determine the frequency of viral gastrointestinal infections among Brazilian HIV-infected patients with diarrhea. METHODS: A collection of 90 fecal specimens from HIV-infected individuals with diarrhea, previously tested for the presence of bacteria and parasite was analyzed by polymerase chain reaction and sequence analysis for the presence of enteric viruses such as astrovirus, norovirus, rotavirus groups A, B and C, adenovirus, herpes simplex virus, Epstein-Barr virus, cytomegalovirus, and human bocavirus. RESULTS: Twenty patients (22.2%; n = 90 were infected with parasites (11 single infections and nine coinfected with virus. Enteropathogenic bacteria were not found. Virus infections were detected in 28.9% (26/90 of the specimens. Cytomegalovirus was the most common virus detected (24.4%; 22/90. Coinfections with viruses and/or parasite were observed in 10 (11.1% samples. CONCLUSION: Gastrointestinal virus infections were more frequent than parasitic or bacterial infections in this patient population.

  8. Induction of Antibodies and T Cell Responses by a Recombinant Influenza Virus Carrying an HIV-1 TatΔ51–59 Protein in Mice

    Directory of Open Access Journals (Sweden)

    B. Garulli

    2014-01-01

    Full Text Available Recombinant influenza viruses hold promise as vectors for vaccines to prevent transmission of mucosal pathogens. In this study, we generated a recombinant WSN/TatΔ51–59 virus in which Tat protein lacking residues 51 to 59 of the basic domain was inserted into the N-terminus of the hemagglutinin (HA of A/WSN/33 virus. The TatΔ51–59 insertion into the viral HA caused a 2-log reduction in viral titers in cell culture, compared with the parental A/WSN/33 virus, and severely affected virus replication in vivo. Nevertheless, Tat-specific antibodies and T cell responses were elicited upon a single intranasal immunization of BALB/c mice with WSN/TatΔ51–59 virus. Moreover, Tat-specific immune responses were also detected following vaccine administration via the vaginal route. These data provide further evidence that moderately large HIV antigens can be delivered by chimeric HA constructs and elicit specific immune responses, thus increasing the options for the potential use of recombinant influenza viruses, and their derivatives, for prophylactic and therapeutic vaccines.

  9. Preclinical evaluation of an mRNA HIV vaccine combining rationally selected antigenic sequences and adjuvant signals (HTI-TriMix).

    Science.gov (United States)

    Guardo, Alberto C; Joe, Patrick Tjok; Miralles, Laia; Bargalló, Manel E; Mothe, Beatriz; Krasniqi, Ahmet; Heirman, Carlo; García, Felipe; Thielemans, Kris; Brander, Christian; Aerts, Joeri L; Plana, Montserrat

    2017-01-28

    The development of a prophylactic vaccine against HIV-1 has so far not been successful. Therefore, attention has shifted more and more toward the development of novel therapeutic vaccines. Here, we evaluated a new mRNA-based therapeutic vaccine against HIV-1-encoding activation signals (TriMix: CD40L + CD70 + caTLR4) combined with rationally selected antigenic sequences [HIVACAT T-cell immunogen (HTI)] sequence: comprises 16 joined fragments from Gag, Pol, Vif, and Nef). For this purpose, peripheral blood mononuclear cells from HIV-1-infected individuals on cART, lymph node explants from noninfected humans, and splenocytes from immunized mice were collected and several immune functions were measured. Electroporation of immature monocyte-derived dendritic cells from HIV-infected patients with mRNA encoding HTI + TriMix potently activated dendritic cells which resulted in upregulation of maturation markers and cytokine production and T-cell stimulation, as evidenced by enhanced proliferation and cytokine secretion (IFN-γ). Responses were HIV specific and were predominantly targeted against the sequences included in HTI. These findings were confirmed in human lymph node explants exposed to HTI + TriMix mRNA. Intranodal immunizations with HTI mRNA in a mouse model increased antigen-specific cytotoxic T-lymphocyte responses. The addition of TriMix further enhanced cytotoxic responses. Our results suggest that uptake of mRNA, encoding strong activation signals and a potent HIV antigen, confers a T-cell stimulatory capacity to dendritic cells and enhances their ability to stimulate antigen-specific immunity. These findings may pave the way for therapeutic HIV vaccine strategies based on antigen-encoding RNA to specifically target antigen-presenting cells.

  10. Immunogenic compositions comprising human immunodeficiency virus (HIV) mosaic Nef proteins

    Science.gov (United States)

    Korber, Bette T [Los Alamos, NM; Perkins, Simon [Los Alamos, NM; Bhattacharya, Tanmoy [Los Alamos, NM; Fischer, William M [Los Alamos, NM; Theiler, James [Los Alamos, NM; Letvin, Norman [Boston, MA; Haynes, Barton F [Durham, NC; Hahn, Beatrice H [Birmingham, AL; Yusim, Karina [Los Alamos, NM; Kuiken, Carla [Los Alamos, NM

    2012-02-21

    The present invention relates to mosaic clade M HIV-1 Nef polypeptides and to compositions comprising same. The polypeptides of the invention are suitable for use in inducing an immune response to HIV-1 in a human.

  11. A systematic approach for the identification of novel, serologically reactive recombinant Varicella-Zoster Virus (VZV antigens

    Directory of Open Access Journals (Sweden)

    Lueking Angelika

    2010-07-01

    Full Text Available Abstract Background Varicella-Zoster virus causes chickenpox upon primary infection and shingles after reactivation. Currently available serological tests to detect VZV-specific antibodies are exclusively based on antigens derived from VZV-infected cells. Results We present a systematic approach for the identification of novel, serologically reactive VZV antigens. Therefore, all VZV open reading frames were cloned into a bacterial expression vector and checked for small scale recombinant protein expression. Serum profiling experiments using purified VZV proteins and clinically defined sera in a microarray revealed 5 putative antigens (ORFs 1, 4, 14, 49, and 68. These were rearranged in line format and validated with pre-characterized sera. Conclusions The line assay confirmed the seroreactivity of the identified antigens and revealed its suitability for VZV serodiagnostics comparable to commercially available VZV-ELISA. Recombinant ORF68 (gE proved to be an antigen for high-confidence determination of VZV serostatus. Furthermore, our data suggest that a serological differentiation between chickenpox and herpes zoster may be possible by analysis of the IgM-portfolio against individual viral antigens.

  12. A Sensitive Method for Detecting Zika Virus Antigen in Patients' Whole-Blood Specimens as an Alternative Diagnostic Approach.

    Science.gov (United States)

    Lum, Fok-Moon; Lin, Cui; Susova, Olga Y; Teo, Teck-Hui; Fong, Siew-Wai; Mak, Tze-Minn; Lee, Linda Kay; Chong, Chia-Yin; Lye, David C B; Lin, Raymond T P; Merits, Andres; Leo, Yee-Sin; Ng, Lisa F P

    2017-07-15

    Epidemics caused by the reemergence of Zika virus (ZIKV) warrant the need to develop new diagnostic measures to complement currently used detection methods. In this study, we explored the detection of ZIKV antigen in a defined leukocyte subset from patients' whole-blood specimens. Whole-blood samples were obtained at the acute and early convalescent phases from ZIKV-infected patients during the Singapore outbreak in August-September 2016. Presence of ZIKV antigen was determined by flow cytometry staining for intracellular ZIKV NS3, using a ZIKV-specific polyclonal antibody. The presence of ZIKV antigen was determined in CD45+CD14+ monocytes. Data showed that ZIKV NS3 antigen could be detected in CD45+CD14+ monocytes. The levels of detection were further categorized into 3 groups: high (positivity among >40% of monocytes), moderate (positivity among 10%-40%), and low (positivity among ZIKV antigen detected at later time points, some patients displayed higher levels as the disease progressed. Our data highlights an alternative approach in using flow cytometry as a sensitive method for detecting ZIKV antigen in whole blood. Importantly, it further confirms the role of CD14+ monocytes as an important cellular target for ZIKV infection during the viremic phase.

  13. Herpes viruses and HIV-1 drug resistance mutations influence the virologic and immunologic milieu of the male genital tract.

    Science.gov (United States)

    Gianella, Sara; Morris, Sheldon R; Anderson, Christy; Spina, Celsa A; Vargas, Milenka V; Young, Jason A; Richman, Douglas D; Little, Susan J; Smith, Davey M

    2013-01-02

    To further understand the role that chronic viral infections of the male genital tract play on HIV-1 dynamics and replication. Retrospective, observational study including 236 paired semen and blood samples collected from 115 recently HIV-1 infected antiretroviral naive men who have sex with men. In this study, we evaluated the association of seminal HIV-1 shedding to coinfections with seven herpes viruses, blood plasma HIV-1 RNA levels, CD4 T-cell counts, presence of transmitted drug resistance mutations (DRMs) in HIV-1 pol, participants' age and stage of HIV-infection using multivariate generalized estimating equation methods. Associations between herpes virus shedding, seminal HIV-1 levels, number and immune activation of seminal T-cells was also investigated (Mann-Whitney). Seminal herpes virus shedding was observed in 75.7% of individuals. Blood HIV-1 RNA levels (P herpes virus (HHV)-8 levels (P herpes viruses seminal shedding in our cohort. Shedding of CMV, EBV and HHV-8 and absence of DRM were associated with increased frequency of HIV-1 shedding and/or higher levels of HIV-1 RNA in semen, which are likely important cofactors for HIV-1 transmission.

  14. Chimeric foot-and-mouth disease virus serotype O displaying a serotype Asia1 antigenic epitope at the surface.

    Science.gov (United States)

    Biswal, Jitendra K; Ranjan, Rajeev; Pattnaik, Bramhadev

    2016-09-01

    To determine whether the G-H loop of foot-and-mouth disease virus (FMDV) serotype O can function as a target structure to harbour and display serotype Asia1 antigenic epitope at the surface. Using reverse genetics, FMDV serotype O IND R2/1975 displaying a FMDV serotype Asia1 B cell epitope at the capsid surface was constructed. The epitope-inserted recombinant chimeric virus was genetically stable up to ten serial passages in cell culture and exhibited growth properties similar to the parental serotype O virus. Furthermore, the surface-displayed Asia1 epitope able to react with serotype Asia1 specific antibodies in a competitive ELISA. Importantly, the recombinant chimeric virus showed neutralizing activity to both serotype O and Asia1 polyclonal antibodies. The capsid protein of FMDV serotype O can effectively display potent epitope of other serotypes, making this an attractive approach for the design of new generation bi-valent FMD vaccines.

  15. Research On Human Immunodeficiency Virus (HIV) In Malawi: The ...

    African Journals Online (AJOL)

    Rates of sexually transmitted diseases (STDs). The incidence of gonorrhoea, trichomoniasis, genital ulcers and genital warts among the cohort ofr644 HIV-I seropositive and 677 HIV-l seronegative women is shown in Table 3. The cumulative incidence of these diseases was significantly higher in HIV-l seropositive than in.

  16. Geminiviral vectors based on bean yellow dwarf virus for production of vaccine antigens and monoclonal antibodies in plants.

    Science.gov (United States)

    Chen, Qiang; He, Junyun; Phoolcharoen, Waranyoo; Mason, Hugh S

    2011-03-01

    Expression of recombinant vaccine antigens and monoclonal antibodies using plant viral vectors has developed extensively during the past several years. The approach benefits from high yields of recombinant protein obtained within days after transient delivery of viral vectors to leaves of Nicotiana benthamiana, a tobacco relative. Modified viral genomes of both RNA and DNA viruses have been created. Geminiviruses such as bean yellow dwarf virus (BeYDV) have a small, single stranded DNA genome that replicates in the nucleus of an infected plant cell, using the cellular DNA synthesis apparatus and a virus-encoded replication initiator protein (Rep). BeYDV-derived expression vectors contain deletions of the viral genes encoding coat and movement proteins and insertion of an expression cassette for a protein of interest. Delivery of the geminiviral vector to leaf cells via Agrobacterium-mediated delivery produces very high levels of recombinant DNA that can act as a transcription template, yielding high levels of mRNA for the protein of interest. Several vaccine antigens, including Norwalk virus capsid protein and hepatitis B core antigen, were expressed using the BeYDV vector at levels up to 1 mg per g of leaf mass. BeYDV replicons can be stacked in the same vector molecule by linking them in tandem, which enables production of multi-subunit proteins like monoclonal antibody (mAb) heavy and light chains. The protective mAb 6D8 against Ebola virus was produced at 0.5 mg per g of leaf mass. Multi-replicon vectors could be conveniently used to produce protein complexes, e.g. virus-like particles that require two or more subunits.

  17. Development and Evaluation of a Rapid Antigen Detection and Serotyping Lateral Flow Antigen Detection System for Foot-and-Mouth Disease Virus.

    Directory of Open Access Journals (Sweden)

    Kazuki Morioka

    Full Text Available We developed a lateral flow strip using monoclonal antibodies (MAbs which allows for rapid antigen detection and serotyping of foot-and-mouth disease virus (FMDV. This FMDV serotyping strip was able to detect all 7 serotypes and distinguish serotypes O, A, C and Asia1. Its sensitivities ranged from 10(3 to 10(4 of a 50% tissue culture infectious dose of each FMDV stain; this is equal to those of the commercial product Svanodip (Boehringer Ingelheim Svanova, Uppsala, Sweden, which can detect all seven serotypes of FMDV, but does not distinguish them. Our evaluation of the FMDV serotyping strip using a total of 118 clinical samples (vesicular fluids, vesicular epithelial emulsions and oral and/or nasal swabs showed highly sensitive antigen detection and accuracy in serotyping in accordance with ELISA or RT-PCR. To the best of our knowledge, this is the first report on any FMDV serotyping strip that provides both rapid antigen detection and serotyping of FMDV at the same time on one strip without extra devices. This method will be useful in both FMD-free countries and FMD-infected countries, especially where laboratory diagnosis cannot be carried out.

  18. HIV-1 alters the cytokine microenvironment and effector function of CD8+T cells upon antigen-specific activation with mycobacteria

    Science.gov (United States)

    Tuberculosis is the most common opportunistic infection in individuals living with human immunodeficiency virus (HIV). In addition to CD4+ T cell depletion, HIV infection compromises the function of CD8+ T cell-mediated immunity to Mycobacterium tuberculosis (M.tb). These effects on susceptibility ...

  19. Epidemiology of infections with intestinal parasites and human immunodeficiency virus (HIV) among sugar-estate residents in Ethiopia

    NARCIS (Netherlands)

    Fontanet, A. L.; Sahlu, T.; Rinke de Wit, T.; Messele, T.; Masho, W.; Woldemichael, T.; Yeneneh, H.; Coutinho, R. A.

    2000-01-01

    Intestinal parasitic infections could play an important role in the progression of infection with human immunodeficiency virus (HIV), by further disturbing the immune system whilst it is already engaged in the fight against HIV. HIV and intestinal parasitic infections were investigated in 1239,

  20. Vaccinia virus G8R protein: a structural ortholog of proliferating cell nuclear antigen (PCNA.

    Directory of Open Access Journals (Sweden)

    Melissa Da Silva

    Full Text Available BACKGROUND: Eukaryotic DNA replication involves the synthesis of both a DNA leading and lagging strand, the latter requiring several additional proteins including flap endonuclease (FEN-1 and proliferating cell nuclear antigen (PCNA in order to remove RNA primers used in the synthesis of Okazaki fragments. Poxviruses are complex viruses (dsDNA genomes that infect eukaryotes, but surprisingly little is known about the process of DNA replication. Given our previous results that the vaccinia virus (VACV G5R protein may be structurally similar to a FEN-1-like protein and a recent finding that poxviruses encode a primase function, we undertook a series of in silico analyses to identify whether VACV also encodes a PCNA-like protein. RESULTS: An InterProScan of all VACV proteins using the JIPS software package was used to identify any PCNA-like proteins. The VACV G8R protein was identified as the only vaccinia protein that contained a PCNA-like sliding clamp motif. The VACV G8R protein plays a role in poxvirus late transcription and is known to interact with several other poxvirus proteins including itself. The secondary and tertiary structure of the VACV G8R protein was predicted and compared to the secondary and tertiary structure of both human and yeast PCNA proteins, and a high degree of similarity between all three proteins was noted. CONCLUSIONS: The structure of the VACV G8R protein is predicted to closely resemble the eukaryotic PCNA protein; it possesses several other features including a conserved ubiquitylation and SUMOylation site that suggest that, like its counterpart in T4 bacteriophage (gp45, it may function as a sliding clamp ushering transcription factors to RNA polymerase during late transcription.

  1. Plant Virus Particles Carrying Tumour Antigen Activate TLR7 and Induce High Levels of Protective Antibody

    Science.gov (United States)

    Jobsri, Jantipa; Allen, Alex; Rajagopal, Deepa; Shipton, Michael; Kanyuka, Kostya; Lomonossoff, George P.; Ottensmeier, Christian; Diebold, Sandra S.; Stevenson, Freda K.; Savelyeva, Natalia

    2015-01-01

    Induction of potent antibody is the goal of many vaccines targeted against infections or cancer. Modern vaccine designs that use virus-like particles (VLP) have shown efficacy for prophylactic vaccination against virus-associated cancer in the clinic. Here we used plant viral particles (PVP), which are structurally analogous to VLP, coupled to a weak idiotypic (Id) tumour antigen, as a conjugate vaccine to induce antibody against a murine B-cell malignancy. The Id-PVP vaccine incorporates a natural adjuvant, the viral ssRNA, which acts via TLR7. It induced potent protective anti-Id antibody responses in an in vivo mouse model, superior to the “gold standard” Id vaccine, with prevalence of the IgG2a isotype. Combination with alum further increased antibody levels and maintained the IgG2a bias. Engagement of TLR7 in vivo was followed by secretion of IFN-α by plasmacytoid dendritic cells and by activation of splenic CD11chi conventional dendritic cells. The latter was apparent from up-regulation of co-stimulatory molecules and from secretion of a wide range of inflammatory cytokines and chemokines including the Th1-governing cytokine IL-12, in keeping with the IgG2a antibody isotype distribution. PVP conjugates are a novel cancer vaccine design, offering an attractive molecular form, similar to VLP, and providing T-cell help. In contrast to VLP, they also incorporate a safe “in-built” ssRNA adjuvant. PMID:25692288

  2. Hepatitis B virus e antigen induces activation of rat hepatic stellate cells

    Energy Technology Data Exchange (ETDEWEB)

    Zan, Yanlu [Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Zhang, Yuxia, E-mail: yzhang@wehi.edu.au [Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101 (China); Tien, Po, E-mail: tienpo@sun.im.ac.cn [Center for Molecular Virology, CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101 (China)

    2013-06-07

    Highlights: •HBeAg expression in HSCs induced production of ECM protein and liver fibrotic markers. •The activation and proliferation of HSCs were mediated by TGF-β. •HBeAg protein purified from cell medium directly activated HSCs. -- Abstract: Chronic hepatitis B virus infection is a major cause of hepatic fibrosis, leading to liver cirrhosis and hepatocellular carcinoma. Hepatitis B virus e antigen (HBeAg) is an accessory protein of HBV, not required for viral replication but important for natural infection in vivo. Hepatic stellate cells (HSCs) are the major producers of excessive extracellular matrix during liver fibrogenesis. Therefore, we examined the influence of HBeAg on HSCs. The rat HSC line HSC-T6 was transfected with HBeAg plasmids, and expression of α-smooth muscle actin, collagen I, transforming growth factor-β1 (TGF-β), and tissue inhibitors of metalloproteinase 1 (TIMP-1) was investigated by quantitative real-time PCR. The proliferation of HSCs was determined by MTS analysis. HBeAg transduction induced up-regulation of these fibrogenic genes and proliferation of HSCs. We found that HBeAg induced TGF-β secretion in HSCs, and the activation of HSCs was prevented by a neutralizing anti-TGF-β antibody. Depletion and addition of HBeAg protein in conditioned medium from HSC-T6 cells transduced with HBeAg indicated that HBeAg directly induced the activation and proliferation of rat primary HSCs. Taken together, HBeAg induces the activation and proliferation of HSCs, mainly mediated by TGF-β, and HBeAg protein purified from cell medium can directly activate HSCs.

  3. Evaluation of single-round infectious, chimeric dengue type 1 virus as an antigen for dengue functional antibody assays.

    Science.gov (United States)

    Yamanaka, Atsushi; Suzuki, Ryosuke; Konishi, Eiji

    2014-07-23

    Dengue fever and dengue hemorrhagic fever are endemic throughout tropical and subtropical countries. Four serotypes of dengue viruses (DENV-1 to DENV-4), each with several genotypes including various subclades, are co-distributed in most endemic areas. Infection-neutralizing and -enhancing antibodies are believed to play protective and pathogenic roles, respectively. Measurement of these functional antibodies against a variety of viral strains is thus important for evaluating coverage and safety of dengue vaccine candidates. Although transportation of live virus materials beyond national borders is increasingly limited, this difficulty may be overcome using biotechnology that enables generation of an antibody-assay antigen equivalent to authentic virus based on viral sequence information. A rapid system to produce flavivirus single-round infectious particles (SRIPs) was recently developed using a Japanese encephalitis virus (JEV) subgenomic replicon plasmid. This system allows production of chimeric SRIPs that have surface proteins of other flaviviruses. In the present study, SRIPs of DENV-1 (D1-SRIPs) were evaluated as an antigen for functional antibody assays. Inclusion of the whole mature capsid gene of JEV into the replicon plasmid provided higher D1-SRIP yields than did its exclusion in cases where a DENV-1 surface-protein-expressing plasmid was used for co-transfection of 293T cells with the replicon plasmid. In an assay to measure the balance between neutralizing and enhancing activities, dose (antibody dilution)-dependent activity curves in dengue-immune human sera or mouse monoclonal antibodies obtained using D1-SRIP antigen were equivalent to those obtained using DENV-1 antigen. Similar results were obtained using additional DENV-2 and DENV-3 systems. In a conventional Vero-cell neutralization test, a significant correlation was shown between antibody titers obtained using D1-SRIP and DENV-1 antigens. These results demonstrate the utility of D1-SRIPs as

  4. Lack of enhancing effect of human anti-human immunodeficiency virus type 1 (HIV-1) antibody on HIV-1 infection of human blood monocytes and peritoneal macrophages.

    OpenAIRE

    Shadduck, P P; Weinberg, J B; Haney, A. F.; Bartlett, J. A.; Langlois, A J; Bolognesi, D P; Matthews, T J

    1991-01-01

    The influence of human anti-human immunodeficiency virus type 1 (HIV-1) antibody on HIV-1 infection of freshly isolated normal human peritoneal macrophages and blood monocytes was examined. Each of 14 HIV antibody-positive human serum samples was found to block the infection of four virus isolates (human T-cell lymphotropic virus type IIIBa-L [HTLV-IIIBa-L], HTLV-IIIB, D.U. 6587-7, and D.U. 7887-8) at serum dilutions ranging from 10(-1) to 10(-2). Three of these isolates (HTLV-IIIBa-L, D.U. 6...

  5. Associations among Epstein-Barr virus subtypes, human leukocyte antigen class I alleles, and the development of posttransplantation lymphoproliferative disorder in bone marrow transplant recipients

    NARCIS (Netherlands)

    Görzer, Irene; Puchhammer-Stöckl, Elisabeth; van Esser, Joost W J; Niesters, Hubert G M; Cornelissen, Jan J

    2007-01-01

    The association between Epstein-Barr virus subtype, human leukocyte antigen class I alleles, and the development of posttransplantation lymphoproliferative disorder was examined in a group of 25 bone marrow transplant recipients. A highly statistically significant correlation was observed between

  6. Morphologic appearance of inclusion bodies and their association with the antigenic composition of naturally occurring rabies viruses.

    OpenAIRE

    Loretu, K; Blenden, D.C.; Torres-Anjel, M J; Satalowich, F T

    1988-01-01

    A total of 112 rabies virus-infected skunk brain samples from naturally occurring cases (64 from Missouri, 48 from Kentucky) were code labeled and grouped into two morphologic categories according to the appearance and size of the discrete particles observed by immunofluorescent-antibody staining. The reactivity of the blind-labeled samples was then determined using a panel of 23 antinucleocapsid monoclonal antibodies to test whether morphologic appearance was associated with antigenicity. Tw...

  7. HIV co-infection with hepatitis B and C viruses among Nigerian ...

    African Journals Online (AJOL)

    Result. The prevalence of HIV/HBV co-infection was 7.7%, while that of HIV/HCV co-infection was 5.2%. No child was co-infected with all three viruses. Children who were co-infected with HCV were more likely to be older than 5 years. There was no significant association between co-infection with either of the hepatitis ...

  8. Detection of human immunodeficiency virus type 1 (HIV-1) Tat protein by aptamer-based biosensors

    Science.gov (United States)

    Hashim, Uda; Fatin, M. F.; Ruslinda, A. R.; Gopinath, Subash C. B.; Uda, M. N. A.

    2017-03-01

    A study was conducted to detect the human immunodeficiency virus (HIV-1) Tat protein using interdigitated electrodes. The measurements and images of the IDEs' finger gaps and the images of chitosan-carbon nanotubes deposited on top of the interdigitated electrodes were taken using the Scanning Electron Microscope. The detection of HIV-1 Tat protein was done using split aptamers and aptamer tail. Biosensors were chosen as diagnostic equipment due to their rapid diagnostic capabilities.

  9. CD4 lymphocyte counts and serum p24 antigen of no diagnostic value in monitoring HIV-infected patients with pulmonary symptoms

    DEFF Research Database (Denmark)

    Orholm, M; Nielsen, T L; Nielsen, Jens Ole

    1990-01-01

    .200 x 10(9)/l, and 60% of patients without OI had CD4 counts less than 0.200 x 10(9)/l; 47 and 42% of patients with and without OI, respectively, had detectable p24 antigen in serum. Only 36% of the patients with OI presented the combination of CD4 cells less than 0.200 x 10(9)/l and p24 in serum......The diagnostic value of the CD4 cell counts and the HIV p24 antigen were evaluated in a consecutive series of 105 HIV-infected patients experiencing 128 episodes of pulmonary symptoms which required bronchoscopy. One-third of patients with opportunistic infection (OI) had CD4 counts greater than 0....... In conclusion, the CD4 cell counts and the presence of p24 antigen in serum had a very limited predictive value for the presence of OI in HIV-infected patients with pulmonary symptoms....

  10. Prevalence of Hepatitis-B Surface Antigen (HbsAg), Hepatitis C ...

    African Journals Online (AJOL)

    The prevalence of Hepatitis-B surface antigen (HBsAg), Hepatitis C virus (HCV) and Human immunodeficiency virus (HIV) was determined among apparently healthy male blood donors in Aminu Kano Teaching Hospital, Kano, between January and December, 2002. A total of 2,288 blood samples from the blood donors ...

  11. Preclinical evaluation of multi antigenic HCV DNA vaccine for the prevention of Hepatitis C virus infection.

    Science.gov (United States)

    Lee, Hyojin; Jeong, Moonsup; Oh, Jooyeon; Cho, Youngran; Shen, Xuefei; Stone, John; Yan, Jian; Rothkopf, Zachary; Khan, Amir S; Cho, Byung Mun; Park, Young K; Weiner, David B; Son, Woo-Chan; Maslow, Joel N

    2017-03-07

    Direct-acting antiviral treatment for hepatitis C virus (HCV) infection is costly and does not protect from re-infection. For human and chimpanzees, recovery from acute HCV infection correlates with host CD4+ and CD8+ T cell responses. DNA plasmids targeting the HCV non-structural antigens NS3, NS4, and NS5, were previously reported to induce robust and sustained T cell responses in mice and primates. These plasmids were combined with a plasmid encoding cytokine IL-28B, together named as VGX-6150. The dose-dependent T cell response and safety of VGX-6150 administered intramuscularly and followed by electroporation was assessed in mice. Immune responses plateaued at 20 μg/dose with IL-28B demonstrating significant immunoadjuvant activity. Mice administered VGX-6150 at 40, 400, and 800 μg given either as a single injection or as 14 injections given bi-weekly over 26 weeks showed no vaccine related changes in any clinical parameter compared to placebo recipients. There was no evidence of VGX-6150 accumulation at the injection site or in any organ 1 month following the 14th vaccination. Based on these studies, the approximate lethal dose (ALD) exceeds 800 μg/dose and the NOAEL was 800 μg/dose in mouse. In conclusion, VGX-6150 appears safe and a promising preventive vaccine candidate for HCV infection.

  12. Neonatal Exposure to Hepatitis C Virus Antigens in Uninfected Children Born to Infected Mothers.

    Science.gov (United States)

    Psaros Einberg, Afrodite; Brenndörfer, Erwin Daniel; Frelin, Lars; Hallberg, Lena; Sällberg, Matti; Fischler, Björn

    2017-09-26

    Vertical transmission of hepatitis C virus (HCV) infection is uncommon and occurs in around 5% of births from HCV infected mothers. The reason for the low transmission rate is unclear. We aimed to investigate if there is evidence of HCV exposure also in the non-infected children born to HCV infected mothers by the presence of a detectable immune response. Serum and peripheral blood mononuclear cells from 9 HCV vertically infected children, 32 uninfected children born to HCV infected mothers, and 15 HCV chronically infected mothers, were analyzed. HCV-RNA negative adults and children were used as controls. HCV specific T cell responses were analyzed by interferon gamma (IFN-γ) using an enzyme-linked immunospot (ELISpot) assay and 3H-thymidine incorporation assay. HCV antibodies were also analyzed. An HCV specific T cell response was detected in 73% (11/15) of the HCV infected mothers, 67% (6/9) of the vertically infected children, 56% (18/32) of the exposed but uninfected children and in 10% and 20% of the control groups, respectively. The two groups of HCV exposed children both had a significantly higher proportion of HCV specific T cell responders compared to pediatric controls (p = 0.01 and p = 0.02). HCV specific immune responses were more common in children born to HCV infected mothers, regardless of the presence of HCV RNA. We conclude that non-infected children born to HCV infected mothers may have been exposed to HCV antigens.

  13. Modulation of Epstein–Barr Virus Nuclear Antigen 2-dependent transcription by protein arginine methyltransferase 5

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Cheng-Der; Cheng, Chi-Ping; Fang, Jia-Shih; Chen, Ling-Chih [Department of Life Sciences, Tzu-Chi University, 701 Chung-Yang Rd. Sec 3, Hualien 97004, Taiwan (China); Zhao, Bo; Kieff, Elliott [Department of Medicine and Microbiology and Molecular Genetics, Channing Laboratory, Brigham and Women’s Hospital and Harvard Medical School, 181 Longwood Ave., Boston 02115, MA (United States); Peng, Chih-Wen, E-mail: pengcw@mail.tcu.edu.tw [Department of Life Sciences, Tzu-Chi University, 701 Chung-Yang Rd. Sec 3, Hualien 97004, Taiwan (China)

    2013-01-18

    Highlights: ► Catalytic active PRMT5 substantially binds to the EBNA2 RG domain. ► PRMT5 augments the EBNA2-dependent transcription. ► PRMT5 triggers the symmetric dimethylation of the EBNA2 RG domain. ► PRMT5 enhances the promoter occupancy of EBNA2 on its target promoters. -- Abstract: Epstein–Barr Virus Nuclear Antigen (EBNA) 2 features an Arginine–Glycine repeat (RG) domain at amino acid positions 335–360, which is a known target for protein arginine methyltransferaser 5 (PRMT5). In this study, we performed protein affinity pull-down assays to demonstrate that endogenous PRMT5 derived from lymphoblastoid cells specifically associated with the protein bait GST-E2 RG. Transfection of a plasmid expressing PRMT5 induced a 2.5- to 3-fold increase in EBNA2-dependent transcription of both the LMP1 promoter in AKATA cells, which contain the EBV genome endogenously, and a Cp-Luc reporter plasmid in BJAB cells, which are EBV negative. Furthermore, we showed that there was a 2-fold enrichment of EBNA2 occupancy in target promoters in the presence of exogenous PRMT5. Taken together, we show that PRMT5 triggers the symmetric dimethylation of EBNA2 RG domain to coordinate with EBNA2-mediated transcription. This modulation suggests that PRMT5 may play a role in latent EBV infection.

  14. Composition of hemagglutinin and neuraminidase affects the antigen yield of influenza A(H1N1)pdm09 candidate vaccine viruses.

    Science.gov (United States)

    Shirakura, Masayuki; Kawaguchi, Akira; Tashiro, Masato; Nobusawa, Eri

    2013-01-01

    To improve the hemagglutinin (HA) antigen yield of influenza A(H1N1)pdm09 candidate vaccine viruses, we generated 7:1, 6:2, and 5:3 genetic reassortant viruses between wild-type (H1N1)pdm09 (A/California/7/2009) (Cal7) and a high-yielding master virus, A/Puerto Rico/8/34 (PR8). These viruses contained the HA; HA and neuraminidase (NA); and HA, NA, and M genes, respectively, derived from Cal7, on a PR8 backbone. The influence of the amino acid residue at position 223 in Cal7 HA on virus growth and HA antigen yield differed between these reassortant viruses. NIIDRG-7, a 7:1 virus possessing arginine at position 223, exhibited a 10-fold higher 50% egg infectious dose (EID(50)) (10.0 log(10)EID(50)/ml) than the 5:3 and 6:2 viruses. It also had 1.5- to 3-fold higher protein (13.8 μg/ml of allantoic fluids) and HA antigen (4.1 μg/ml of allantoic fluids) yields than the 5:3 and 6:2 viruses, which possessed identical Cal7 HA proteins. However, the HA antigen yield of the other 7:1 virus, which possessed glutamine at position 223 was 60% of that of NIIDRG-7. In addition, a novel 6:2 virus possessing Cal7 HA and the NA of A/Wisconsin/10/98 (a triple reassortant swine-like H1N1 virus), produced 107% of the HA yield of NIIDRG-7. In this study, we showed that the balance between HA and NA in the influenza A(H1N1)pdm09 virus affects its protein and antigen yield.

  15. Development and evaluation of two subunit vaccine candidates containing antigens of hepatitis E virus, rotavirus, and astrovirus.

    Science.gov (United States)

    Xia, Ming; Wei, Chao; Wang, Leyi; Cao, Dianjun; Meng, Xiang-Jin; Jiang, Xi; Tan, Ming

    2016-05-19

    Hepatitis E virus (HEV), rotavirus (RV), and astrovirus (AstV) are important pathogens that transmit through a common fecal-oral route, causing hepatitis (HEV) and gastroenteritis (RV and AstV) respectively in humans. In this study, we developed and evaluated two subunit vaccine candidates that consisted of the same protruding or spike protein antigens of the three viruses in two formats, a fusion of the three antigens into one molecule (fused vaccine) vs. a mixture of the three free antigens together (mixed vaccine). Both vaccines were easily made via E. coli expression system. Mouse immunization experiments showed that the fused vaccine elicited significantly higher antibody responses against the three viral antigens than those induced by the mixed vaccine. In addition, the mouse post-immune antisera of the fused vaccine revealed significantly higher neutralizing titers against HEV infection in cell culture, as well as significantly higher 50% blocking titers (BT50) against RV VP8-HBGA receptor interactions than those of the post-immune antisera after immunization of the mixed vaccine. Thus, the fused vaccine is a promising trivalent vaccine candidate against HEV, RV, and AstV, which is worth for further development.

  16. Co-delivery of antigen and IL-12 by Venezuelan equine encephalitis virus replicon particles enhances antigen-specific immune responses and anti-tumor effects

    Science.gov (United States)

    Osada, Takuya; Berglund, Peter; Morse, Michael A.; Hubby, Bolyn; Lewis, Whitney; Niedzwiecki, Donna; Hobeika, Amy; Burnett, Bruce; Devi, Gayathri R.; Clay, Timothy M.; Smith, Jonathan; Lyerly, H. Kim

    2013-01-01

    We recently demonstrated that Venezuelan equine encephalitis (VEE) virus-based replicon particles (VRP) encoding tumor antigens could break tolerance in the immunomodulatory environment of advanced cancer. We hypothesized that local injection of VRP expressing Interleukin-12 (IL-12) at the site of injections of VRP-based cancer vaccines would enhance the tumor-antigen-specific T cell and antibody responses and anti-tumor efficacy. Mice were immunized with VRP encoding the human tumor-associated antigen, carcinoembryonic antigen (CEA) (VRP-CEA(6D)) and VRP-IL-12 was also administered at the same site or at a distant location. CEA-specific T cell and antibody responses were measured. To determine antitumor activity, mice were implanted with MC38-CEA-2 cells and immunized with VRP-CEA with and without VRP-IL-12 and tumor growth and mouse survival were measured. VRP-IL-12 greatly enhanced CEA-specific T cell and antibody responses when combined with VRP-CEA(6D) vaccination. VRP IL-12 was superior to IL-12 protein at enhancing immune responses. Vaccination with VRP-CEA(6D) plus VRP-IL-12 was superior to VRP-CEA(6D) or VRP-IL-12 alone in inducing anti-tumor activity and prolonging survival in tumor-bearing mice. Importantly, local injection of VRP-IL-12 at the VRP-CEA(6D) injection site provided more potent activation of CEA-specific immune responses than VRP-IL-12 injected at a distant site from the VRP-CEA injections. Together, this study shows that VRP-IL-12 enhances vaccination with VRP-CEA(6D) and was more effective at activating CEA-specific T cell responses when locally expressed at the vaccine site. Clinical trials evaluating the adjuvant effect of VRP-IL-12 at enhancing the immunogenicity of cancer vaccines are warranted. PMID:22488274

  17. Co-delivery of antigen and IL-12 by Venezuelan equine encephalitis virus replicon particles enhances antigen-specific immune responses and antitumor effects.

    Science.gov (United States)

    Osada, Takuya; Berglund, Peter; Morse, Michael A; Hubby, Bolyn; Lewis, Whitney; Niedzwiecki, Donna; Yang, Xiao Yi; Hobeika, Amy; Burnett, Bruce; Devi, Gayathri R; Clay, Timothy M; Smith, Jonathan; Kim Lyerly, H

    2012-11-01

    We recently demonstrated that Venezuelan equine encephalitis virus-based replicon particle (VRPs) encoding tumor antigens could break tolerance in the immunomodulatory environment of advanced cancer. We hypothesized that local injection of VRP-expressing interleukin-12 (IL-12) at the site of injections of VRP-based cancer vaccines would enhance the tumor-antigen-specific T cell and antibody responses and antitumor efficacy. Mice were immunized with VRP encoding the human tumor-associated antigen, carcinoembryonic antigen (CEA) (VRP-CEA(6D)), and VRP-IL-12 was also administered at the same site or at a distant location. CEA-specific T cell and antibody responses were measured. To determine antitumor activity, mice were implanted with MC38-CEA-2 cells and immunized with VRP-CEA with and without VRP-IL-12, and tumor growth and mouse survival were measured. VRP-IL-12 greatly enhanced CEA-specific T cell and antibody responses when combined with VRP-CEA(6D) vaccination. VRP-IL-12 was superior to IL-12 protein at enhancing immune responses. Vaccination with VRP-CEA(6D) plus VRP-IL-12 was superior to VRP-CEA(6D) or VRP-IL-12 alone in inducing antitumor activity and prolonging survival in tumor-bearing mice. Importantly, local injection of VRP-IL-12 at the VRP-CEA(6D) injection site provided more potent activation of CEA-specific immune responses than that of VRP-IL-12 injected at a distant site from the VRP-CEA injections. Together, this study shows that VRP-IL-12 enhances vaccination with VRP-CEA(6D) and was more effective at activating CEA-specific T cell responses when locally expressed at the vaccine site. Clinical trials evaluating the adjuvant effect of VRP-IL-12 at enhancing the immunogenicity of cancer vaccines are warranted.

  18. A virus-like particle vaccine candidate for influenza A virus based on multiple conserved antigens presented on hepatitis B tandem core particles.

    Science.gov (United States)

    Ramirez, Alejandro; Morris, Stephen; Maucourant, Sophie; D'Ascanio, Isabella; Crescente, Vincenzo; Lu, I-Na; Farinelle, Sophie; Muller, Claude P; Whelan, Michael; Rosenberg, William

    2018-02-01

    Existing Influenza A virus (IAV) vaccines target variable parts of the virus that may change between seasons. Vaccine design relies on predicting the predominant circulating influenza strains but when there is a mismatch between vaccine and circulating strains, efficacy is sub-optimal. Furthermore, current approaches provide limited protection against emerging influenza strains that may cause pandemics. One solution is to design vaccines that target conserved protein domains of influenza, which remain largely unchanged over time and are likely to be found in emergent variants. We present a virus-like particle (VLP), built using the hepatitis B virus tandem core platform, as an IAV vaccine candidate containing multiple conserved antigens. Hepatitis B core protein spontaneously assembles into a VLP that is immunogenic and confers immunogenicity to proteins incorporated into the major insertion region (MIR) of core monomers. However, insertion of antigen sequences may disrupt particle assembly preventing VLP formation or result in unstable particles. We have overcome these problems by genetically manipulating the hepatitis B core to express core monomers in tandem, ligated with a flexible linker, incorporating different antigens at each of the MIRs. Immunisation with this VLP, named Tandiflu1, containing 4 conserved antigens from matrix protein 2 ectodomain and hemagglutinin stalk, leads to production of cross-reactive and protective antibodies. The polyclonal antibodies induced by Tandiflu1 can bind IAV Group 1 hemagglutinin types H1, H5, H11, H9, H16 and a conserved epitope on matrix protein 2 expressed by most strains of IAV. Vaccination with Tandiflu1 results in 100% protection from a lethal influenza challenge with H1N1 IAV. Serum transfer from vaccinated animals is sufficient to confer protection from influenza-associated illness in naïve mice. These data suggest that a Tandem Core based IAV vaccine might provide broad protection against common and emergent H1

  19. Necroptosis takes place in human immunodeficiency virus type-1 (HIV-1-infected CD4+ T lymphocytes.

    Directory of Open Access Journals (Sweden)

    Ting Pan

    Full Text Available Human immunodeficiency virus type 1 (HIV-1 infection is characterized by progressive depletion of CD4+ T lymphocytes and dysfunction of the immune system. The numbers of CD4+ T lymphocytes in the human body are maintained constantly by homeostatic mechanisms that failed during HIV-1 infection, resulting in progressive loss of CD4+ T cells mainly via apoptosis. Recently, a non-apoptotic form of necrotic programmed cell death, named necroptosis, has been investigated in many biological and pathological processes. We then determine whether HIV-1-infected cells also undergo necroptosis. In this report, we demonstrate that HIV-1 not only induces apoptosis, but also mediates necroptosis in the infected primary CD4+ T lymphocytes and CD4+ T-cell lines. Necroptosis-dependent cytopathic effects are significantly increased in HIV-1-infected Jurkat cells that is lack of Fas-associated protein-containing death domain (FADD, indicating that necroptosis occurs as an alternative cell death mechanism in the absence of apoptosis. Unlike apoptosis, necroptosis mainly occurs in HIV-infected cells and spares bystander damage. Treatment with necrostatin-1(Nec-1, a RIP1 inhibitor that specifically blocks the necroptosis pathway, potently restrains HIV-1-induced cytopathic effect and interestingly, inhibits the formation of HIV-induced syncytia in CD4+ T-cell lines. This suggests that syncytia formation is mediated, at least partially, by necroptosis-related processes. Furthermore, we also found that the HIV-1 infection-augmented tumor necrosis factor-alpha (TNF-α plays a key role in inducing necroptosis and HIV-1 Envelope and Tat proteins function as its co-factors. Taken together,necroptosis can function as an alternative cell death pathway in lieu of apoptosis during HIV-1 infection, thereby also contributing to HIV-1-induced cytopathic effects. Our results reveal that in addition to apoptosis, necroptosis also plays an important role in HIV-1-induced pathogenesis.

  20. Improved humoral and cellular immune response against the gp120 V3 loop of HIV-1 following genetic immunization with a chimeric DNA vaccine encoding the V3 inserted into the hepatites B surface antigen

    DEFF Research Database (Denmark)

    Fomsgaard, A.; Nielsen, H.V.; Bryder, K.

    1998-01-01

    -2d-restricted cytotoxic T lymphocyte (CTL) epitope. In an attempt to improve the immunogenicity of V3 in DNA vaccines, a plasmid expressing MN V3 as a fusion protein with the highly immunogenic middle (pre-S2+S) surface antigen of hepatitis B virus (HBsAg) was constructed. Epidermal inoculation......The gp120-derived V3 loop of HIV-1 is involved in co-receptor interaction, it guides cell tropism, and contains an epitope for antibody neutralization. Thus, HIV-1 V3 is an attractive vaccine candidate. The V3 of the MN strain (MN V3) contains both B- and T-cell epitopes, including a known mouse H...... by gene gun was used for genetic immunization in a mouse model. Antibody and CTL responses to MN V3 and HBsAg were measured and compared with the immune responses obtained after vaccination with plasmids encoding the complete HIV-1 MN gp160 and HBsAg (pre-S2+S), respectively. DNA vaccination with the HIV...

  1. Discrepancies in prevalence trends for HIV, hepatitis B virus, and hepatitis C virus in Haiphong, Vietnam from 2007 to 2012.

    Directory of Open Access Journals (Sweden)

    Azumi Ishizaki

    Full Text Available We previously reported a significant reduction in the prevalence of human immunodeficiency virus type 1 (HIV from 2007 to 2012 in people who inject drugs (PWID; 35.9% to 18.5%, p < 0.001 and female sex workers (FSW; 23.1% to 9.8%, p < 0.05, but not in blood donors (BD or pregnant women, in Haiphong, Vietnam. Our aim in the present study was to assess trends in the prevalence of infection with hepatitis B and C viruses (HBV and HCV, respectively. We also investigated the coinfection rates of HBV and HCV with HIV in the same groups. Between 2007 and 2012, HBV prevalence was significantly decreased in BD (18.1% vs. 9.0%, p = 0.007 and slightly decreased in FSW (11.0% vs. 3.9%, p = 0.21, but not in PWID (10.7% vs. 11.1%, p = 0.84. HCV prevalence was significantly decreased in PWID (62.1% in 2007 vs. 42.7% in 2008, p < 0.0001, but it had rebounded to 58.4% in 2012 (2008 vs. 2012, p < 0.0001. HCV prevalence also increased in FSW: 28.6% in 2007 and 2009 vs. 35.3% in 2012; however, this difference was not significant (2007 vs. 2012, p = 0.41. Rates of coinfection with HBV and HCV among HIV-infected PWID and FSW did not change significantly during the study period. Our findings suggest that the current harm reduction programs designed to prevent HIV transmission in PWID and FSW may be insufficient to prevent the transmission of hepatitis viruses, particularly HCV, in Haiphong, Vietnam. New approaches, such as the introduction of catch-up HBV vaccination to vulnerable adult populations and the introduction of HCV treatment as prevention, should be considered to reduce morbidity and mortality due to HIV and hepatitis virus coinfection in Vietnam.

  2. Short Communication: Inhibition of DC-SIGN-Mediated HIV-1 Infection by Complementary Actions of Dendritic Cell Receptor Antagonists and Env-Targeting Virus Inactivators.

    Science.gov (United States)

    Pustylnikov, Sergey; Dave, Rajnish S; Khan, Zafar K; Porkolab, Vanessa; Rashad, Adel A; Hutchinson, Matthew; Fieschi, Frank; Chaiken, Irwin; Jain, Pooja

    2016-01-01

    The DC-SIGN receptor on human dendritic cells interacts with HIV gp120 to promote both infection of antigen-presenting cells and transinfection of T cells. We hypothesized that in DC-SIGN-expressing cells, both DC-SIGN ligands such as dextrans and gp120 antagonists such as peptide triazoles would inhibit HIV infection with potential complementary antagonist effects. To test this hypothesis, we evaluated the effects of dextran (D66), isomaltooligosaccharides (D06), and several peptide triazoles (HNG156, K13, and UM15) on HIV infection of B-THP-1/DC-SIGN cells. In surface plasmon resonance competition assays, D66 (IC50 = 35.4 μM) and D06 (IC50 = 3.4 mM) prevented binding of soluble DC-SIGN to immobilized mannosylated bovine serum albumin (BSA). An efficacious dose-dependent inhibition of DC-SIGN-mediated HIV infection in both pretreatment and posttreatment settings was observed, as indicated by inhibitory potentials (EC50) [D66 (8 μM), D06 (48 mM), HNG156 (40 μM), UM15 (100 nM), and K13 (25 nM)]. Importantly, both dextrans and peptide triazoles significantly decreased HIV gag RNA levels [D66 (7-fold), D06 (13-fold), HNG156 (7-fold), K-13 (3-fold), and UM15 (6-fold)]. Interestingly, D06 at the highest effective concentration showed a 14-fold decrease of infection, while its combination with 50 μM HNG156 showed a 26-fold decrease. Hence, these compounds can combine to inactivate the viruses and suppress DC-SIGN-mediated virus-cell interaction that as shown earlier leads to dendritic cell HIV infection and transinfection dependent on the DC-SIGN receptor.

  3. The Prevalence of Malaria Antigen In The Serum of HIV Seropositive ...

    African Journals Online (AJOL)

    Alasia Datonye

    seropositive patients with malaria antigen. Methodology: ... distribution and clinical presentations . Malaria is .... The red blood cells are lysed by the diluents, releasing the malaria parasite antigens, which react with the antibody that was embedded on the well. A positive result gives two colored lines (for test and control);.

  4. Chemokine receptors and their crucial role in human immunodeficiency virus infection: major breakthroughs in HIV research

    DEFF Research Database (Denmark)

    Kristiansen, T B; Knudsen, T B; Eugen-Olsen, J

    1998-01-01

    Within the last three years, major progress in the understanding of acquired immune deficiency syndrome pathogenesis has been achieved. The discovery that human immunodeficiency virus (HIV), in addition to the CD4 receptor, requires the presence of a coreceptor in order to infect cells has led...... to a series of breakthroughs in HIV research and knowledge. These include an increased understanding of viral entry, a connection of viral phenotype to specific coreceptor use, and an unequivocal linkage of a single human gene to host susceptibility. All in all these achievements provide a number of promising...... new strategies for combating HIV....

  5. Chemokine receptors and their crucial role in human immunodeficiency virus infection: major breakthroughs in HIV research

    DEFF Research Database (Denmark)

    Kristiansen, T B; Knudsen, T B; Eugen-Olsen, J

    1998-01-01

    to a series of breakthroughs in HIV research and knowledge. These include an increased understanding of viral entry, a connection of viral phenotype to specific coreceptor use, and an unequivocal linkage of a single human gene to host susceptibility. All in all these achievements provide a number of promising......Within the last three years, major progress in the understanding of acquired immune deficiency syndrome pathogenesis has been achieved. The discovery that human immunodeficiency virus (HIV), in addition to the CD4 receptor, requires the presence of a coreceptor in order to infect cells has led...... new strategies for combating HIV....

  6. Analysis of host responses to Mycobacterium tuberculosis antigens in a multi-site study of subjects with different TB and HIV infection states in sub-Saharan Africa.

    Directory of Open Access Journals (Sweden)

    Jayne S Sutherland

    Full Text Available Tuberculosis (TB remains a global health threat with 9 million new cases and 1.4 million deaths per year. In order to develop a protective vaccine, we need to define the antigens expressed by Mycobacterium tuberculosis (Mtb, which are relevant to protective immunity in high-endemic areas.We analysed responses to 23 Mtb antigens in a total of 1247 subjects with different HIV and TB status across 5 geographically diverse sites in Africa (South Africa, The Gambia, Ethiopia, Malawi and Uganda. We used a 7-day whole blood assay followed by IFN-γ ELISA on the supernatants. Antigens included PPD, ESAT-6 and Ag85B (dominant antigens together with novel resuscitation-promoting factors (rpf, reactivation proteins, latency (Mtb DosR regulon-encoded antigens, starvation-induced antigens and secreted antigens.There was variation between sites in responses to the antigens, presumably due to underlying genetic and environmental differences. When results from all sites were combined, HIV- subjects with active TB showed significantly lower responses compared to both TST(- and TST(+ contacts to latency antigens (Rv0569, Rv1733, Rv1735, Rv1737 and the rpf Rv0867; whilst responses to ESAT-6/CFP-10 fusion protein (EC, PPD, Rv2029, TB10.3, and TB10.4 were significantly higher in TST(+ contacts (LTBI compared to TB and TST(- contacts fewer differences were seen in subjects with HIV co-infection, with responses to the mitogen PHA significantly lower in subjects with active TB compared to those with LTBI and no difference with any antigen.Our multi-site study design for testing novel Mtb antigens revealed promising antigens for future vaccine development. The IFN-γ ELISA is a cheap and useful tool for screening potential antigenicity in subjects with different ethnic backgrounds and across a spectrum of TB and HIV infection states. Analysis of cytokines other than IFN-γ is currently on-going to determine correlates of protection, which may be useful for vaccine

  7. Direct Phenotypical and Functional Dysregulation of Primary Human B Cells by Human Immunodeficiency Virus (HIV) Type 1 In Vitro

    OpenAIRE

    Ana Judith Perisé-Barrios; María Ángeles Muñoz-Fernandez; Marjorie Pion

    2012-01-01

    BACKGROUND: Human immunodeficiency virus type 1 (HIV-1) induces a general dysregulation of immune system. Dysregulation of B cell compartment is generally thought to be induced by HIV-related immune activation and lymphopenia. However, a direct influence of HIV-1 particles on B cells was recently proposed as the third pathway of B cells dysregulation. METHODS/PRINCIPAL FINDINGS: We evaluated the direct and specific consequences of HIV-1 contact on activation, survival, proliferation and pheno...

  8. Synthetic biology design to display an 18 kDa rotavirus large antigen on a modular virus-like particle.

    Science.gov (United States)

    Lua, Linda H L; Fan, Yuanyuan; Chang, Cindy; Connors, Natalie K; Middelberg, Anton P J

    2015-11-04

    Virus-like particles are an established class of commercial vaccine possessing excellent function and proven stability. Exciting developments made possible by modern tools of synthetic biology has stimulated emergence of modular VLPs, whereby parts of one pathogen are by design integrated into a less harmful VLP which has preferential physical and manufacturing character. This strategy allows the immunologically protective parts of a pathogen to be displayed on the most-suitable VLP. However, the field of modular VLP design is immature, and robust design principles are yet to emerge, particularly for larger antigenic structures. Here we use a combination of molecular dynamic simulation and experiment to reveal two key design principles for VLPs. First, the linkers connecting the integrated antigenic module with the VLP-forming protein must be well designed to ensure structural separation and independence. Second, the number of antigenic domains on the VLP surface must be sufficiently below the maximum such that a "steric barrier" to VLP formation cannot exist. This second principle leads to designs whereby co-expression of modular protein with unmodified VLP-forming protein can titrate down the amount of antigen on the surface of the VLP, to the point where assembly can proceed. In this work we elucidate these principles by displaying the 18.1 kDa VP8* domain from rotavirus on the murine polyomavirus VLP, and show functional presentation of the antigenic structure. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Antigenic drift of H1N1 influenza A virus in pigs with and without passive immunity.

    Science.gov (United States)

    Diaz, Andres; Allerson, Matthew; Culhane, Marie; Sreevatsan, Srinand; Torremorell, Montserrat

    2013-12-01

    The genetic and antigenic characteristics of influenza A viruses (IAV) within and between species change over time due to antigenic shift and drift. Although pigs are known to play a key role in the epidemiology of IAV between species, little is known about the molecular evolution of IAV hemagglutinin (HA) in pigs. The aim of this study was to evaluate the HA drift of an H1N1 IAV after infecting weaned pigs with or without maternally derived passive immunity. Three- to four-week-old piglets born either to vaccinated or unvaccinated sows were contact-infected upon exposure with an IAV-infected pig. Nasal swabs were collected daily from each pig and tested for IAV by RRT-PCR. Full-length HA sequences were obtained directly from positive nasal swabs and compared between groups. Synonymous and non-synonymous mutations were detected in pigs with and without passive immunity. Most of the non-synonymous mutations occurred within the HA1 region of the HA. Changes within HA1 region were only identified in antigenic site B in pigs without passive immunity and in antigenic sites A, B, and D in pigs with passive immunity. However, there was no association between the immune status of the pig and the amino acid substitutions observed. Overall, we demonstrated that amino acid substitutions within antigenic sites can happen in weaned pigs with or without passive immunity shortly after infection. © 2013 Blackwell Publishing Ltd.

  10. A Novel Prime and Boost Regimen of HIV Virus-Like Particles with TLR4 Adjuvant MPLA Induces Th1 Oriented Immune Responses against HIV.

    Directory of Open Access Journals (Sweden)

    Ethan Poteet

    Full Text Available HIV virus-like particles (VLPs present the HIV envelope protein in its native conformation, providing an ideal vaccine antigen. To enhance the immunogenicity of the VLP vaccine, we sought to improve upon two components; the route of administration and the additional adjuvant. Using HIV VLPs, we evaluated sub-cheek as a novel route of vaccine administration when combined with other conventional routes of immunization. Of five combinations of distinct prime and boost sequences, which included sub-cheek, intranasal, and intradermal routes of administration, intranasal prime and sub-cheek boost (IN+SC resulted in the highest HIV-specific IgG titers among the groups tested. Using the IN+SC regimen we tested the adjuvant VesiVax Conjugatable Adjuvant Lipid Vesicles (CALV + monophosphoryl lipid A (MPLA at MPLA concentrations of 0, 7.5, 12.5, and 25 μg/dose in combination with our VLPs. Mice that received 12.5 or 25 μg/dose MPLA had the highest concentrations of Env-specific IgG2c (20.7 and 18.4 μg/ml respectively, which represents a Th1 type of immune response in C57BL/6 mice. This was in sharp contrast to mice which received 0 or 7.5 μg MPLA adjuvant (6.05 and 5.68 μg/ml of IgG2c respectively. In contrast to IgG2c, MPLA had minor effects on Env-specific IgG1; therefore, 12.5 and 25 μg/dose of MPLA induced the optimal IgG1/IgG2c ratio of 1.3. Additionally, the percentage of germinal center B cells increased significantly from 15.4% in the control group to 31.9% in the CALV + 25 μg MPLA group. These mice also had significantly more IL-2 and less IL-4 Env-specific CD8+ T cells than controls, correlating with an increased percentage of Env-specific central memory CD4+ and CD8+ T cells. Our study shows the strong potential of IN+SC as an efficacious route of administration and the effectiveness of VLPs combined with MPLA adjuvant to induce Env specific Th1-oriented HIV-specific immune responses.

  11. T Cell Reactivity against Mycolyl Transferase Antigen 85 of M. tuberculosis in HIV-TB Coinfected Subjects and in AIDS Patients Suffering from Tuberculosis and Nontuberculous Mycobacterial Infections

    Directory of Open Access Journals (Sweden)

    Pascal Launois

    2011-01-01

    Full Text Available The mycolyl transferase antigen 85 complex is a major secreted protein family from mycobacterial culture filtrate, demonstrating powerful T cell stimulatory properties in most HIV-negative, tuberculin-positive volunteers with latent M.tuberculosis infection and only weak responses in HIV-negative tuberculosis patients. Here, we have analyzed T cell reactivity against PPD and Ag85 in HIV-infected individuals, without or with clinical symptoms of tuberculosis, and in AIDS patients with disease caused by nontuberculous mycobacteria. Whereas responses to PPD were not significantly different in HIV-negative and HIV-positive tuberculin-positive volunteers, responses to Ag85 were significantly decreased in the HIV-positive (CDC-A and CDC-B group. Tuberculosis patients demonstrated low T cell reactivity against Ag85, irrespective of HIV infection, and finally AIDS patients suffering from NTM infections were completely nonreactive to Ag85. A one-year follow-up of twelve HIV-positive tuberculin-positive individuals indicated a decreased reactivity against Ag85 in patients developing clinical tuberculosis, highlighting the protective potential of this antigen.

  12. Genetic diversity-independent neutralization of pandemic viruses (e.g. HIV), potentially pandemic (e.g. H5N1 strain of influenza) and carcinogenic (e.g. HBV and HCV) viruses and possible agents of bioterrorism (variola) by enveloped virus neutralizing compounds (EVNCs).

    Science.gov (United States)

    Kotwal, Girish J

    2008-06-06

    Genetic diversity and hypermutation contribute to difficulties in developing a vaccine against viruses like HIV and influenza. There are currently no known immune correlates of protection against HIV. This has made the development of a vaccine against HIV that would provide sterilizing immunity in the near future an impossible task. The abandonment of a recent AIDS vaccine human trial due to a failure to elicit a protective sterilising immune response confirms that empirical attempts to develop a vaccine may result in failures. Also the difficulty in predicting the next pandemic strain of influenza may make it difficult to respond rapidly should there be an outbreak. Therefore, it is time to explore broad spectrum agents that can target either the lipid portion of the envelope or the sugar moieties of the glycoproteins or the rafts (regions within viral and cell envelopes where a higher concentration of the glycoproteins exist). Broad spectrum agents that can serve as disrafters or neutralize the viral infectivity by binding to the envelope lipid or sugar moieties will not be affected by the vagaries of hypermutation of surface antigens. This is because the post-translation modification is a host function. Presented here is a review of recently reported agents present in pomegranate juice (polyphenols, beta-sitosterol, sugars and ellagic acid) and fulvic acid, described here as the envelope virus neutralising compounds (EVNCs) and complex molecules like lectins and mucins. Pomegranate juice was previously reported to inactivate HIV and further shown by our group to inactivate influenza, herpes viruses and poxviruses. A formulation consisting of fulvic acid, a complex mixture of compounds was previously reported to render vaccinia virus, HIV and SARS virus non-infectious. Recently, both fulvic acid and pomegranate juice have been shown to inactivate genetically diverse strains of influenza including H5N1, further confirming the broad spectrum nature of these agents

  13. Heterosubtypic protection against pathogenic human and avian influenza viruses via in vivo electroporation of synthetic consensus DNA antigens.

    Directory of Open Access Journals (Sweden)

    Dominick J Laddy

    antigenic drift that will likely occur before these viruses cross the species barrier to humans.

  14. Parasitic helminths and HIV-1 infection: the effect of immunomodulatory antigens

    NARCIS (Netherlands)

    Mouser, E.E.I.M.

    2016-01-01

    In many regions of the world co-infection with parasitic helminths and HIV-1 is common. Both pathogens have major implications for the host immune system, helminths possess immunomodulatory properties whilst HIV-1 infects and kills immune cells. Currently very little is known regarding what effects

  15. Small molecule and peptide-mediated inhibition of Epstein-Barr virus nuclear antigen 1 dimerization

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun Young; Song, Kyung-A [Samsung Advanced Institute for Health Sciences and Technology (SAIHST), Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Samsung Biomedical Research Institute (SBRI), Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Kieff, Elliott [Department of Medicine, Brigham and Women' s Hospital and Harvard Medical School, Boston, MA 02115 (United States); Kang, Myung-Soo, E-mail: mkang@skku.edu [Samsung Advanced Institute for Health Sciences and Technology (SAIHST), Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Samsung Biomedical Research Institute (SBRI), Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Department of Medicine, Brigham and Women' s Hospital and Harvard Medical School, Boston, MA 02115 (United States)

    2012-07-27

    Highlights: Black-Right-Pointing-Pointer Evidence that targeting EBNA1 dimer, an EBV onco-antigen, can be achievable. Black-Right-Pointing-Pointer A small molecule and a peptide as EBNA1 dimerization inhibitors identified. Black-Right-Pointing-Pointer Both inhibitors associated with EBNA1 and blocked EBNA1 DNA binding activity. Black-Right-Pointing-Pointer Also, prevented its dimerization, and repressed viral gene transcription. -- Abstract: Latent Epstein-Barr virus (EBV) infection is associated with human B cell lymphomas and certain carcinomas. EBV episome persistence, replication, and gene expression are dependent on EBV-encoded nuclear antigen 1 (EBNA1)'s DNA binding domain (DBD)/dimerization domain (DD)-mediated sequence-specific DNA binding activity. Homodimerization of EBNA1 is essential for EBNA1 DNA binding and transactivation. In this study, we characterized a novel small molecule EBNA1 inhibitor EiK1, screened from the previous high throughput screening (HTS). The EiK1 compound specifically inhibited the EBNA1-dependent, OriP-enhanced transcription, but not EBNA1-independent transcription. A Surface Plasmon Resonance Biacore assay revealed that EiK1 associates with EBNA1 amino acid 459-607 DBD/DD. Consistent with the SPR data, in vitro gel shift assays showed that EiK1 suppressed the activity of EBNA1 binding to the cognate familial repeats (FR) sequence, but not control RBP-J{kappa} binding to the J{kappa} site. Subsequently, a cross-linker-mediated in vitro multimerization assay and EBNA1 homodimerization-dependent yeast two-hybrid assay showed that EiK1 significantly inhibited EBNA1 dimerization. In an attempt to identify more highly specific peptide inhibitors, small peptides encompassing the EBNA1 DBD/DD were screened for inhibition of EBNA1 DBD-mediated DNA binding function. The small peptide P85, covering EBNA1 a.a. 560-574, significantly blocked EBNA1 DNA binding activity in vitro, prevented dimerization in vitro and in vivo, associated

  16. Amino Acids in Hemagglutinin Antigenic Site B Determine Antigenic and Receptor Binding Differences between A(H3N2)v and Ancestral Seasonal H3N2 Influenza Viruses

    Science.gov (United States)

    Wang, Xiaoquan; Ilyushina, Natalia A.; Lugovtsev, Vladimir Y.; Bovin, Nicolai V.; Couzens, Laura K.; Gao, Jin

    2016-01-01

    ABSTRACT Influenza A H3N2 variant [A(H3N2)v] viruses, which have caused human infections in the United States in recent years, originated from human seasonal H3N2 viruses that were introduced into North American swine in the mid-1990s, but they are antigenically distinct from both the ancestral and current circulating H3N2 strains. A reference A(H3N2)v virus, A/Minnesota/11/2010 (MN/10), and a seasonal H3N2 strain, A/Beijing/32/1992 (BJ/92), were chosen to determine the molecular basis for the antigenic difference between A(H3N2)v and the ancestral viruses. Viruses containing wild-type and mutant MN/10 or BJ/92 hemagglutinins (HAs) were constructed and probed for reactivity with ferret antisera against MN/10 and BJ/92 in hemagglutination inhibition assays. Among the amino acids that differ between the MN/10 and BJ/92 HAs, those in antigenic site A had little impact on the antigenic phenotype. Within antigenic site B, mutations at residues 156, 158, 189, and 193 of MN/10 HA to those in BJ/92 switched the MN/10 antigenic phenotype to that of BJ/92. Mutations at residues 156, 157, 158, 189, and 193 of BJ/92 HA to amino acids present in MN/10 were necessary for BJ/92 to become antigenically similar to MN/10. The HA amino acid substitutions responsible for switching the antigenic phenotype also impacted HA binding to sialyl receptors that are usually present in the human respiratory tract. Our study demonstrates that antigenic site B residues play a critical role in determining both the unique antigenic phenotype and receptor specificity of A(H3N2)v viruses, a finding that may facilitate future surveillance and risk assessment of novel influenza viruses. IMPORTANCE Influenza A H3N2 variant [A(H3N2)v] viruses have caused hundreds of human infections in multiple states in the United States since 2009. Most cases have been children who had contact with swine in agricultural fairs. These viruses originated from human seasonal H3N2 viruses that were introduced into the U

  17. Respiratory viruses in young South African children with acute lower respiratory infections and interactions with HIV.

    Science.gov (United States)

    Annamalay, Alicia A; Abbott, Salome; Sikazwe, Chisha; Khoo, Siew-Kim; Bizzintino, Joelene; Zhang, Guicheng; Laing, Ingrid; Chidlow, Glenys R; Smith, David W; Gern, James; Goldblatt, Jack; Lehmann, Deborah; Green, Robin J; Le Souëf, Peter N

    2016-08-01

    Human rhinovirus (RV) is the most common respiratory virus and has been associated with frequent and severe acute lower respiratory infections (ALRI). The prevalence of RV species among HIV-infected children in South Africa is unknown. To describe the prevalence of respiratory viruses, including RV species, associated with HIV status and other clinical symptoms in children less than two years of age with and without ALRI in Pretoria, South Africa. Nasopharyngeal aspirates were collected from 105 hospitalized ALRI cases and 53 non-ALRI controls less than two years of age. HIV status was determined. Common respiratory viruses were identified by PCR, and RV species and genotypes were identified by semi-nested PCR, sequencing and phylogenetic tree analyses. Respiratory viruses were more common among ALRI cases than controls (83.8% vs. 69.2%; p=0.041). RV was the most commonly identified virus in cases with pneumonia (45.6%) or bronchiolitis (52.1%), regardless of HIV status, as well as in controls (39.6%). RV-A was identified in 26.7% of cases and 15.1% of controls while RV-C was identified in 21.0% of cases and 18.9% of controls. HIV-infected children were more likely to be diagnosed with pneumonia than bronchiolitis (pinfected cases (n=15) compared with 30.6% of HIV-uninfected cases (n=85, p=0.013), and was identified more frequently in bronchiolitis than in pneumonia cases (43.8% vs. 12.3%; pinfection may be protective against RSV and bronchiolitis. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Treponema pallidum and Hepatitis B virus co-infection among HIV ...

    African Journals Online (AJOL)

    Co infection of T.pallidum and hepatitis B virus occurred in 2/130 (1.5%) of participants. There were no any factors that significantly associated with positive hepatitis B surface antigen while multiple sexual partners and history of sexually transmitted diseases were significantly associated with positive syphilis test (P= 0.023 ...

  19. Effects of the I559P gp41 change on the conformation and function of the human immunodeficiency virus (HIV-1 membrane envelope glycoprotein trimer.

    Directory of Open Access Journals (Sweden)

    Nirmin Alsahafi

    Full Text Available The mature human immunodeficiency virus (HIV-1 envelope glycoprotein (Env trimer is produced by proteolytic cleavage of a precursor and consists of three gp120 exterior and three gp41 transmembrane subunits. The metastable Env complex is induced to undergo conformational changes required for virus entry by the binding of gp120 to the receptors, CD4 and CCR5/CXCR4. An isoleucine-to-proline change (I559P in the gp41 ectodomain has been used to stabilize soluble forms of HIV-1 Env trimers for structural characterization and for use as immunogens. In the native membrane-anchored HIV-1BG505 Env, the I559P change modestly decreased proteolytic maturation, increased the non-covalent association of gp120 with the Env trimer, and resulted in an Env conformation distinctly different from that of the wild-type HIV-1BG505 Env. Compared with the wild-type Env, the I559P Env was recognized inefficiently by polyclonal sera from HIV-1-infected individuals, by several gp41-directed antibodies, by some antibodies against the CD4-binding site of gp120, and by antibodies that preferentially recognize the CD4-bound Env. Some of the gp120-associated antigenic differences between the wild-type HIV-1BG505 Env and the I559P mutant were compensated by the SOS disulfide bond between gp120 and gp41, which has been used to stabilize cleaved soluble Env trimers. Nonetheless, regardless of the presence of the SOS changes, Envs with proline 559 were recognized less efficiently than Envs with isoleucine 559 by the VRC01 neutralizing antibody, which binds the CD4-binding site of gp120, and the PGT151 neutralizing antibody, which binds a hybrid gp120-gp41 epitope. The I559P change completely eliminated the ability of the HIV-1BG505 Env to mediate cell-cell fusion and virus entry, and abolished the capacity of the SOS Env to support virus infection in the presence of a reducing agent. These results suggest that differences exist between the quaternary structures of functional Env

  20. Antigenic and genomic characterization of human influenza A and B viruses circulating in Argentina after the introduction of influenza A(H1N1)pdm09.

    Science.gov (United States)

    Russo, Mara L; Pontoriero, Andrea V; Benedetti, Estefania; Czech, Andrea; Avaro, Martin; Periolo, Natalia; Campos, Ana M; Savy, Vilma L; Baumeister, Elsa G

    2014-12-01

    This study was conducted as part of the Argentinean Influenza and other Respiratory Viruses Surveillance Network, in the context of the Global Influenza Surveillance carried out by the World Health Organization (WHO). The objective was to study the activity and the antigenic and genomic characteristics of circulating viruses for three consecutive seasons (2010, 2011 and 2012) in order to investigate the emergence of influenza viral variants. During the study period, influenza virus circulation was detected from January to December. Influenza A and B, and all current subtypes of human influenza viruses, were present each year. Throughout the 2010 post-pandemic season, influenza A(H1N1)pdm09, unexpectedly, almost disappeared. The haemagglutinin (HA) of the A(H1N1)pdm09 viruses studied were segregated in a different genetic group to those identified during the 2009 pandemic, although they were still antigenically closely related to the vaccine strain A/California/07/2009. Influenza A(H3N2) viruses were the predominant strains circulating during the 2011 season, accounting for nearly 76 % of influenza viruses identified. That year, all HA sequences of the A(H3N2) viruses tested fell into the A/Victoria/208/2009 genetic clade, but remained antigenically related to A/Perth/16/2009 (reference vaccine recommended for this three-year period). A(H3N2) viruses isolated in 2012 were antigenically closely related to A/Victoria/361/2011, recommended by the WHO as the H3 component for the 2013 Southern Hemisphere formulation. B viruses belonging to the B/Victoria lineage circulated in 2010. A mixed circulation of viral variants of both B/Victoria and B/Yamagata lineages was detected in 2012, with the former being predominant. A(H1N1)pdm09 viruses remained antigenically closely related to the vaccine virus A/California/7/2009; A(H3N2) viruses continually evolved into new antigenic clusters and both B lineages, B/Victoria/2/87-like and B/Yamagata/16/88-like viruses, were observed

  1. PROPHYLACTIC MEASURES AGAINST INFECTION WITH HEPATITIS C VIRUS AND HIV IN INFANTS

    Directory of Open Access Journals (Sweden)

    Gorazd Lešničar

    2004-04-01

    Full Text Available Background. The World Health Organization estimates that every year more then 500,000 infants get infected with human immunodeficiency virus (HIV and 10,000– 60,000 with hepatitis C virus (HCV worldwide.Rapid and early diagnosis of HCV and HIV infection in exposed infants is rendered difficult because of transplacental passage of maternal IgG antibodies to the virus that are present in infants up to 18 months of age. Mother-to-infant transmission of HCV is comparatively uncommon. Furthermore, chronic hepatitis C does not appear to worsen the outcome of pregnancy or predispose fetal abnormalities.The rate of mother-to-infant transmission is 4 to 7% per pregnancy in women with HCV viremia. Perinatal infection with HCV is usually asymptomatic. Concomitant infection in pregnant women with HIV increases the rate of transmission of HCV infection 4 to 5 fold. Cesarean section is not recommended and current available medications against HCV infection are contraindicated because of fetal toxicity. Breast-feeding poses no relevant risk of HCV transmission.Conclusions. Perinatal transmission of HIV from mother to child accounts to 5 to 10% of acquired HIV infections worldwide. It is by far the major source of infection and represents more that 90% of all infections in children. Transmission of HIV occurs either before birth, during delivery or through breastfeeding.Recently, zidovudine and some other antiretrovirals administered during pregnancy, at delivery, and in the first 6 weeks of life to the infant have reduced transmission by more than two thirds (from 25 to less than 5%. The experts have also recommended elective cesarean section and dissuaded HIV positive mothers from breastfeeding.Experts must also test strategies to further decrease the risk for perinatal HCV and HIV infection. Significant progress in the area of new safe and effective vaccines is eagerly expected.

  2. Measurement of antibodies to varicella-zoster virus using a virus-free fluorescent-antibody-to-membrane-antigen (FAMA) test.

    Science.gov (United States)

    Park, Rackhyun; Hwang, Ji Young; Lee, Kang Il; Namkoong, Sim; Choi, Seuk-Keun; Park, Songyong; Park, Hosun; Park, Junsoo

    2015-02-01

    The fluorescent-antibody-to-membrane-antigen (FAMA) test is regarded as the "gold standard" to detect protective antibodies to varicella-zoster virus (VZV) because of its high sensitivity and specificity. Because the classic FAMA test uses an infectious virus for detection of antibodies to VZV, it is labor-intensive, and also requires special equipment for handling the virus. For this reason, we attempted to develop a simple and safe FAMA assay. Because VZV glycoprotein E (gE) is one of the major VZV glycoproteins, we used the gE protein for the FAMA test (gE FAMA). Here, we demonstrate that overexpression of gE in HEK293T cells can be used to measure antibodies in human serum, and that gE FAMA titers are closely correlated with gpEIA ELISA data. These results indicate that our gE FAMA test has the potential to measure antibodies to VZV.

  3. Hepatitis B virus-like particles access major histocompatibility class I and II antigen presentation pathways in primary dendritic cells.

    Science.gov (United States)

    Moffat, Jessica M; Cheong, Wan-Shoo; Villadangos, José A; Mintern, Justine D; Netter, Hans J

    2013-04-26

    Virus-like particles (VLPs) represent high density displays of viral proteins that efficiently trigger immunity. VLPs composed of