Antigen sensitivity is a major determinant of CD8+ T-cell polyfunctionality and HIV-suppressive activity.

Science.gov (United States)

Almeida, Jorge R; Sauce, Delphine; Price, David A; Papagno, Laura; Shin, So Youn; Moris, Arnaud; Larsen, Martin; Pancino, Gianfranco; Douek, Daniel C; Autran, Brigitte; Sáez-Cirión, Asier; Appay, Victor

2009-06-18

CD8(+) T cells are major players in the immune response against HIV. However, recent failures in the development of T cell-based vaccines against HIV-1 have emphasized the need to reassess our basic knowledge of T cell-mediated efficacy. CD8(+) T cells from HIV-1-infected patients with slow disease progression exhibit potent polyfunctionality and HIV-suppressive activity, yet the factors that unify these properties are incompletely understood. We performed a detailed study of the interplay between T-cell functional attributes using a bank of HIV-specific CD8(+) T-cell clones isolated in vitro; this approach enabled us to overcome inherent difficulties related to the in vivo heterogeneity of T-cell populations and address the underlying determinants that synthesize the qualities required for antiviral efficacy. Conclusions were supported by ex vivo analysis of HIV-specific CD8(+) T cells from infected donors. We report that attributes of CD8(+) T-cell efficacy against HIV are linked at the level of antigen sensitivity. Highly sensitive CD8(+) T cells display polyfunctional profiles and potent HIV-suppressive activity. These data provide new insights into the mechanisms underlying CD8(+) T-cell efficacy against HIV, and indicate that vaccine strategies should focus on the induction of HIV-specific T cells with high levels of antigen sensitivity to elicit potent antiviral efficacy.

HLA-DP antigens in HIV-infected individuals

DEFF Research Database (Denmark)

Ødum, Niels; Georgsen, J; Fugger, L

1991-01-01

We studied the distribution of HLA-DP antigens in 74 HIV-infected Danish homosexual men and 188 ethnically matched healthy individuals, using the primed lymphocyte typing (PLT) technique. Forty of the patients developed AIDS within 3 years after diagnosis, whereas the remaining 34 were healthy...... or had only minor symptoms for 3 years or more (median observation time was 42 months). HLA-DPwl seemed to be decreased (relative risk = 0.3) in AIDS patients (5.0 per cent) when compared to patients with minor symptoms (14.7 per cent) and healthy controls (14.9 per cent). These differences were, however...

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

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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.

Specific Antibody Production by Blood B Cells is Retained in Late Stage Drug-naïve HIV-infected Africans

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Lydie Béniguel

2004-01-01

Full Text Available Unseparated peripheral blood mononuclear cells (PBMCs obtained from drug-naïve African individuals living in a context of multi-infections and presenting with high viral load (VL, were cultured in vitro and tested for their ability to produce antibodies (Abs reacting with HIV-1 antigens. Within these PBMCs, circulating B cells were differentiated in vitro and produced IgG Abs against not only ENV, but also GAG and POL proteins. Under similar experimental conditions, HAART treated patients produced Abs to ENV proteins only. The in vitro antibody production by drug-naïve individuals' PBMCs depended on exogenous cytokines (IL-2 and IL-10 but neither on the re-stimulation of reactive cells in cultures by purified HIV-1-gp 160 antigen nor on the re-engagement of CD40 surface molecules. Further, it was not abrogated by the addition of various monoclonal Abs (mAbs to co-stimulatory molecules. This suggests that the in vitro antibody production by drug-naïve individuals' PBMCs resulted from the maturation of already envelope and core antigen-primed, differentiated B cells, presumably pre-plasma cells, which are not known to circulate at homeostasy. As in vitro produced Abs retained the capacity of binding antigen and forming complexes, this study provides pre-clinical support for functional humoral responses despite major HIV- and other tropical pathogen-induced B cell perturbations.

Detection of a human intracisternal A-type retroviral particle antigenically related to HIV

Science.gov (United States)

Garry, R. F.; Fermin, C. D.; Hart, D. J.; Alexander, S. S.; Donehower, L. A.; Luo-Zhang, H.

1990-01-01

Sjogren's syndrome is an autoimmune disease that is characterized by dryness of the mouth and eyes. The loss of salivary and lacrimal gland function is accompanied by lymphocytic infiltration. Because similar symptoms and glandular pathology are observed in certain persons infected with human immunodeficiency virus (HIV), a search was initiated for a possible retroviral etiology in this syndrome. A human intracisternal A-type retroviral particle that is antigenically related to HIV was detected in lymphoblastoid cells exposed to homogenates of salivary tissue from patients with Sjogren's syndrome. Comparison of this retroviral particle to HIV indicates that they are distinguishable by several ultrastructural, physical, and enzymatic criteria.

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

CSIR Research Space (South Africa)

Meyers, A

2008-06-23

Full Text Available Open AcceResearch article Expression of HIV-1 antigens in plants as potential subunit vaccines Ann Meyers1,2, Ereck Chakauya1,2,3, Enid Shephard1,4, Fiona L Tanzer1,2, James Maclean1,2, Alisson Lynch1,2, Anna-Lise Williamson1,5 and Edward P Rybicki...Figure 1 The HIV-1 Gag-derived proteins used in this study. Scale diagram showing (A) native Pr55Gag ORF organisation in the Page 2 of 15 (page number not for citation purposes) gag gene, (B) the p17/p24 fusion protein ORF, (C) p24 ORF. ORFs labelled p7...

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 ....... 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.......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.......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...

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.

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....

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.

Screening Yield of HIV Antigen/Antibody Combination and Pooled HIV RNA Testing for Acute HIV Infection in a High-Prevalence Population.

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Peters, Philip J; Westheimer, Emily; Cohen, Stephanie; Hightow-Weidman, Lisa B; Moss, Nicholas; Tsoi, Benjamin; Hall, Laura; Fann, Charles; Daskalakis, Demetre C; Beagle, Steve; Patel, Pragna; Radix, Asa; Foust, Evelyn; Kohn, Robert P; Marmorino, Jenni; Pandori, Mark; Fu, Jie; Samandari, Taraz; Gay, Cynthia L

2016-02-16

Although acute HIV infection contributes disproportionately to onward HIV transmission, HIV testing has not routinely included screening for acute HIV infection. To evaluate the performance of an HIV antigen/antibody (Ag/Ab) combination assay to detect acute HIV infection compared with pooled HIV RNA testing. Multisite, prospective, within-individual comparison study conducted between September 2011 and October 2013 in 7 sexually transmitted infection clinics and 5 community-based programs in New York, California, and North Carolina. Participants were 12 years or older and seeking HIV testing, without known HIV infection. All participants with a negative rapid HIV test result were screened for acute HIV infection with an HIV Ag/Ab combination assay (index test) and pooled human immunodeficiency virus 1 (HIV-1) RNA testing. HIV RNA testing was the reference standard, with positive reference standard result defined as detectable HIV-1 RNA on an individual RNA test. Number and proportion with acute HIV infections detected. Among 86,836 participants with complete test results (median age, 29 years; 75.0% men; 51.8% men who have sex with men), established HIV infection was diagnosed in 1158 participants (1.33%) and acute HIV infection was diagnosed in 168 participants (0.19%). Acute HIV infection was detected in 134 participants with HIV Ag/Ab combination testing (0.15% [95% CI, 0.13%-0.18%]; sensitivity, 79.8% [95% CI, 72.9%-85.6%]; specificity, 99.9% [95% CI, 99.9%-99.9%]; positive predictive value, 59.0% [95% CI, 52.3%-65.5%]) and in 164 participants with pooled HIV RNA testing (0.19% [95% CI, 0.16%-0.22%]; sensitivity, 97.6% [95% CI, 94.0%-99.4%]; specificity, 100% [95% CI, 100%-100%]; positive predictive value, 96.5% [95% CI, 92.5%-98.7%]; sensitivity comparison, P testing detected 82% of acute HIV infections detectable by pooled HIV RNA testing. Compared with rapid HIV testing alone, HIV Ag/Ab combination testing increased the relative HIV diagnostic yield (both

Autocrine production of beta-chemokines protects CMV-Specific CD4 T cells from HIV infection.

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Joseph P Casazza

2009-10-01

Full Text Available Induction of a functional subset of HIV-specific CD4+ T cells that is resistant to HIV infection could enhance immune protection and decrease the rate of HIV disease progression. CMV-specific CD4+ T cells, which are less frequently infected than HIV-specific CD4+ T cells, are a model for such an effect. To determine the mechanism of this protection, we compared the functional response of HIV gag-specific and CMV pp65-specific CD4+ T cells in individuals co-infected with CMV and HIV. We found that CMV-specific CD4+ T cells rapidly up-regulated production of MIP-1alpha and MIP-1beta mRNA, resulting in a rapid increase in production of MIP-1alpha and MIP-1beta after cognate antigen stimulation. Production of beta-chemokines was associated with maturational phenotype and was rarely seen in HIV-specific CD4+ T cells. To test whether production of beta-chemokines by CD4+ T cells lowers their susceptibility to HIV infection, we measured cell-associated Gag DNA to assess the in vivo infection history of CMV-specific CD4+ T cells. We found that CMV-specific CD4+ T cells which produced MIP-1beta contained 10 times less Gag DNA than did those which failed to produce MIP-1beta. These data suggest that CD4+ T cells which produce MIP-1alpha and MIP-1beta bind these chemokines in an autocrine fashion which decreases the risk of in vivo HIV infection.

Predictive value of prostate specific antigen in a European HIV-positive cohort

DEFF Research Database (Denmark)

Shepherd, Leah; Borges, Álvaro H; Ravn, Lene

2016-01-01

BACKGROUND: It is common practice to use prostate specific antigen (PSA) ≥4.0 ng/ml as a clinical indicator for men at risk of prostate cancer (PCa), however, this is unverified in HIV+ men. We aimed to describe kinetics and predictive value of PSA for PCa in HIV+ men. METHODS: A nested case...... control study of 21 men with PCa and 40 matched-controls within EuroSIDA was conducted. Prospectively stored plasma samples before PCa (or matched date in controls) were measured for the following markers: total PSA (tPSA), free PSA (fPSA), testosterone and sex hormone binding globulin (SHBG). Conditional...... logistic regression models investigated associations between markers and PCa. Mixed models were used to describe kinetics. Sensitivity and specificity of using tPSA >4 ng/ml to predict PCa was calculated. Receiver operating characteristic curves were used to identify optimal cutoffs in HIV+ men for total...

Delayed-type hypersensitivity skin test responses to PPD and other antigens among BCG-vaccinated HIV-1-infected and healthy children and adolescents.

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Costa, Natalia Moriya Xavierda; Albuquerque, Maly de; Lins, Janaína Bacelar Acioli; Alvares-Junior, João Teixeira; Stefani, Mariane Martins de Araújo

2011-10-01

Among HIV-1-infected patients, CD4+ T cell counts are well-established markers of cell-mediated immunity. Delayed-type hypersensitivity (DTH) skin tests can be used to evaluate in vivo cell-mediated immunity to common antigens. DTH responses to tuberculin purified protein derivative (PPD), sporotrichin, trichophytin, candidin and streptokinase/streptodornase antigens were assessed. Thirty-six HIV-1-infected children/adolescents and 56 age- and sex-matched HIV-1/HIV-2-seronegative participants were tested. All participants had a BCG scar. Fisher's exact test was used to evaluate significant differences between groups (pPPD positivity prevailed among healthy participants (40/56, 71.4%). PPD reactivity in the HIV-1-positive group was 8.3% (pPPD induration was 2.5mm (range: 2-5mm) in the HIV-1 group and 6.0 mm among healthy participants (range: 3-15 mm). There was no correlation between PPD positivity and age. No correlation between CD4+ T cell counts and DTH reactivity was observed among HIV-1-infected patients. DTH skin test responses, including PPD reactivity, were significantly lower among HIV-1-infected participants compared to healthy controls, which likely reflects advanced disease and T cell depletion.

Natural Products and HIV/AIDS.

Science.gov (United States)

Cary, Daniele C; Peterlin, B Matija

2018-01-01

The study of natural products in biomedical research is not a modern concept. Many of the most successful medical therapeutics are derived from natural products, including those studied in the field of HIV/AIDS. Biomedical research has a rich history of discovery based on screens of medicinal herbs and traditional medicine practices. Compounds derived from natural products, which repress HIV and those that activate latent HIV, have been reported. It is important to remember the tradition in medical research to derive therapies based on these natural products and to overcome the negative perception of natural products as an "alternative medicine."

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.

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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

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.

The link between CD8⁺ T-cell antigen-sensitivity and HIV-suppressive capacity depends on HLA restriction, target epitope and viral isolate.

Science.gov (United States)

Lissina, Anna; Fastenackels, Solène; Inglesias, Maria C; Ladell, Kristin; McLaren, James E; Briceño, Olivia; Gostick, Emma; Papagno, Laura; Autran, Brigitte; Sauce, Delphine; Price, David A; Saez-Cirion, Asier; Appay, Victor

2014-02-20

Although it is established that CD8 T-cell immunity is critical for the control of HIV replication in vivo, the key factors that determine antiviral efficacy are yet to be fully elucidated. Antigen-sensitivity and T-cell receptor (TCR) avidity have been identified as potential determinants of CD8⁺ T-cell efficacy. However, there is no general consensus in this regard because the relationship between these parameters and the control of HIV infection has been established primarily in the context of immunodominant CD8⁺ T-cell responses against the Gag₂₆₃₋₂₇₂ KK10 epitope restricted by human leukocyte antigen (HLA)-B27. To investigate the relationship between antigen-sensitivity, TCR avidity and HIV-suppressive capacity in vitro across epitope specificities and HLA class I restriction elements, we used a variety of techniques to study CD8⁺ T-cell clones specific for Nef₇₃₋₈₂ QK10 and Gag₂₀₋₂₉ RY10, both restricted by HLA-A3, alongside CD8⁺ T-cell clones specific for Gag₂₆₃₋₂₇₂ KK10. For each targeted epitope, the linked parameters of antigen-sensitivity and TCR avidity correlated directly with antiviral efficacy. However, marked differences in HIV-suppressive capacity were observed between epitope specificities, HLA class I restriction elements and viral isolates. Collectively, these data emphasize the central role of the TCR as a determinant of CD8⁺ T-cell efficacy and demonstrate that the complexities of antigen recognition across epitope and HLA class I boundaries can confound simple relationships between TCR engagement and HIV suppression.

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

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...... of intrapatient adaptations, is predictable, facilitates viral subtype diversification, and increases global HIV diversity. Because low epitope abundance is associated with infrequent and weak T cell responses, this most likely results in both population-level immune evasion and inadequate responses in most...

Quarter Century of Anti-HIV CAR T Cells.

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Wagner, Thor A

2018-04-01

A therapy that might cure HIV is a very important goal for the 30-40 million people living with HIV. Chimeric antigen receptor T cells have recently had remarkable success against certain leukemias, and there are reasons to believe they could be successful for HIV. This manuscript summarizes the published research on HIV CAR T cells and reviews the current anti-HIV chimeric antigen receptor strategies. Research on anti-HIV chimeric antigen receptor T cells has been going on for at least the last 25 years. First- and second-generation anti-HIV chimeric antigen receptors have been developed. First-generation anti-HIV chimeric antigen receptors were studied in clinical trials more than 15 years ago, but did not have meaningful clinical efficacy. There are some reasons to be optimistic about second-generation anti-HIV chimeric antigen receptor T cells, but they have not yet been tested in vivo.

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...

IMMUNOLOGICAL CHARACTERISTIC OF SYNTHETIC PEPTIDES SIMILAR TO ACTUAL HIV ANTIGEN DETERMINANTS

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S. V. Korobova

2016-01-01

Full Text Available The development of HIV vaccine remains an important goal in prophylaxis and therapy of HIV/ AIDS epidemics. There are various approaches for development of а candidate vaccine based on induction of neutralizing antibodies and cell-mediated immunity. Synthetic peptides are considered promising vaccine antigens since they are capable of activating both humoral and cellular immune response. HIV-1 envelope gp120 is the target for neutralizing antiviral antibodies. The V3 region of the HIV-1 gp120 is highly immunogenic and important for the virus-coreceptor interaction. In a RV144 vaccine trial, the levels of vaccine-induced IgG antibodies recognizing V1V2 regions from multiple HIV-1 subtypes show inverse correlations with a risk for HIV-1 infection. Meanwhile, HIV is characterized by high diversity. The consensus and mosaic immunogens are complete but artificial proteins, which are computationally designed to elicit immune responses with improved cross-reactive broadness. We have been studied immunogenic properties of synthetic peptides derived from V1, V2, V3 loop regions of the consensus M HIV1 (CON-S sequence group of the gp 120 envelope protein and V3 loop derived from a Russian RUA022a2 isolate. These peptides specifically reacted to HIV-positive sera in ELISA, thus indicating their similarity to appropriate HIV proteins. The peptides proved to be weakly immunogenic. Therefore, Freund complete adjuvant was used to enhance peptide immunogenicity. To assess the immunogenicity, the mice were immunized with a peptide mixture. Antibodies have been developed to every peptide from the mixture, being, predominantly, of IgG isotype. The antibody titers depended on the length of peptide sequences. However, the sera from immunized mice did not have a HIV neutralizing activity. The serum neutralization was assessed by pseudovirus-based assay, using a molecular clone of virus isolates CAP 45.2.00.G3 and QH.209.14.M.EnvA2. The virus neutralization is a

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...

Mature IgM-expressing plasma cells sense antigen and develop competence for cytokine production upon antigenic challenge

Science.gov (United States)

Blanc, Pascal; Moro-Sibilot, Ludovic; Barthly, Lucas; Jagot, Ferdinand; This, Sébastien; de Bernard, Simon; Buffat, Laurent; Dussurgey, Sébastien; Colisson, Renaud; Hobeika, Elias; Fest, Thierry; Taillardet, Morgan; Thaunat, Olivier; Sicard, Antoine; Mondière, Paul; Genestier, Laurent; Nutt, Stephen L.; Defrance, Thierry

2016-01-01

Dogma holds that plasma cells, as opposed to B cells, cannot bind antigen because they have switched from expression of membrane-bound immunoglobulins (Ig) that constitute the B-cell receptor (BCR) to production of the secreted form of immunoglobulins. Here we compare the phenotypical and functional attributes of plasma cells generated by the T-cell-dependent and T-cell-independent forms of the hapten NP. We show that the nature of the secreted Ig isotype, rather than the chemical structure of the immunizing antigen, defines two functionally distinct populations of plasma cells. Fully mature IgM-expressing plasma cells resident in the bone marrow retain expression of a functional BCR, whereas their IgG+ counterparts do not. Antigen boost modifies the gene expression profile of IgM+ plasma cells and initiates a cytokine production program, characterized by upregulation of CCL5 and IL-10. Our results demonstrate that IgM-expressing plasma cells can sense antigen and acquire competence for cytokine production upon antigenic challenge. PMID:27924814

Anti-HIV-1 B cell responses are dependent on B cell precursor frequency and antigen-binding affinity.

Science.gov (United States)

Dosenovic, Pia; Kara, Ervin E; Pettersson, Anna-Klara; McGuire, Andrew T; Gray, Matthew; Hartweger, Harald; Thientosapol, Eddy S; Stamatatos, Leonidas; Nussenzweig, Michel C

2018-04-16

The discovery that humans can produce potent broadly neutralizing antibodies (bNAbs) to several different epitopes on the HIV-1 spike has reinvigorated efforts to develop an antibody-based HIV-1 vaccine. Antibody cloning from single cells revealed that nearly all bNAbs show unusual features that could help explain why it has not been possible to elicit them by traditional vaccination and instead would require a sequence of different immunogens. This idea is supported by experiments with genetically modified immunoglobulin (Ig) knock-in mice. Sequential immunization with a series of specifically designed immunogens was required to shepherd the development of bNAbs. However, knock-in mice contain superphysiologic numbers of bNAb precursor-expressing B cells, and therefore how these results can be translated to a more physiologic setting remains to be determined. Here we make use of adoptive transfer experiments using knock-in B cells that carry a synthetic intermediate in the pathway to anti-HIV-1 bNAb development to examine how the relationship between B cell receptor affinity and precursor frequency affects germinal center (GC) B cell recruitment and clonal expansion. Immunization with soluble HIV-1 antigens can recruit bNAb precursor B cells to the GC when there are as few as 10 such cells per mouse. However, at low precursor frequencies, the extent of clonal expansion is directly proportional to the affinity of the antigen for the B cell receptor, and recruitment to GCs is variable and dependent on recirculation.

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

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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.

IgM response to a human Pneumocystis carinii surface antigen in HIV-infected patients with pulmonary symptoms

DEFF Research Database (Denmark)

Lundgren, Bettina; Kovacs, J A; Mathiesen, Lars Reinhardt

1993-01-01

We have developed an ELISA to detect IgM antibodies to a major human Pneumocystis carinii surface antigen (gp95), and investigated the IgM response in 128 HIV-infected patients who underwent bronchoscopy for evaluation of pulmonary symptoms. Only 5 (4%) patients had IgM antibodies to P. carinii g...

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...

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

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Hønge, Bl; Jespersen, S; Medina, C; Té, Ds; da Silva, Zj; Ostergaard, L; Laursen, Al; Wejse, C; Krarup, H; Erikstrup, C

2014-10-01

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 to detect HBV surface antigen (HBsAg) and anti-HCV among HIV-infected patients in Guinea-Bissau. Blood samples from HIV-infected patients in Guinea-Bissau were stored after testing for HBsAg and anti-HCV with rapid tests. Samples were subsequently re-tested for HBsAg and anti-HCV in Denmark. Two rapid tests were used in Guinea-Bissau: HBsAg Strip Ref 2034 (VEDA.LAB, Alençon, France; sensitivity 62.3%; specificity 99.2%) and HEPA-SCAN (Bhat Bio-Tech, Bangalore, India; sensitivity 57.1%; specificity 99.7%). In the two tests the ability to obtain the correct outcome depended on the antigen and antibody concentrations, respectively. Sex, age, CD4 cell count and antiretroviral therapy status did not differ between false negative and true positive samples in either of the tests. The study is limited by a low number of anti-HCV positive samples. New diagnostic rapid tests should always be evaluated in the setting in which they will be used before implementation. © 2014 British HIV Association.

Antigenic analyses of tissues and excretory and secretory products from Strongylus vulgaris.

Science.gov (United States)

Wynne, E; Slocombe, J O; Wilkie, B N

1981-07-01

Rabbit antisera were prepared against veronal buffered saline extracts of L4 and L5 Strongylus vulgaris, adult S. vulgaris and adult Strongylus equinus retrieved from naturally infected horses. In agar gel diffusion with these antisera, adult S vulgaris and S. equinus each appeared to have at least one unique antigen; larval S. vulgaris appeared to have two species-specific and two stage-specific antigens. There were several common antigens. Excretory and secretory products were collected also from L4 and L5 an maintained over several days in tissue culture fluid. In agar gel diffusion against the above rabbit antisera, a stage-specific antigen was found also in excretory and secretory products. In addition, excretory and secretory products had three antigens in common with adult and larval S. vulgaris, but only one of these was common to adult S. equinus. The excretory and secretory products appear, therefore, to have two species-specific and one stage-specific antigens.

IgM response to a human Pneumocystis carinii surface antigen in HIV-infected patients with pulmonary symptoms

DEFF Research Database (Denmark)

Lundgren, Bettina; Kovacs, J A; Mathiesen, Lars Reinhardt

1993-01-01

We have developed an ELISA to detect IgM antibodies to a major human Pneumocystis carinii surface antigen (gp95), and investigated the IgM response in 128 HIV-infected patients who underwent bronchoscopy for evaluation of pulmonary symptoms. Only 5 (4%) patients had IgM antibodies to P. carinii gp...... response to gp95. These patients also showed an increase in IgG antibodies to gp95 and had microbiologically proven PCP. Prior to the development of the IgM response, IgG antibodies to gp95 were detectable in all 3 patients. Thus, HIV-infected patients with PCP seldom produce IgM antibodies to the major...

A novel strategy for efficient production of anti-V3 human scFvs against HIV-1 clade C

Directory of Open Access Journals (Sweden)

Kumar Rajesh

2012-11-01

Full Text Available Abstract Background Production of human monoclonal antibodies that exhibit broadly neutralizing activity is needed for preventing HIV-1 infection, however only a few such antibodies have been generated till date. Isolation of antibodies by the hybridoma technology is a cumbersome process with fewer yields. Further, the loss of unstable or slowly growing clones which may have unique binding specificities often occurs during cloning and propagation and the strongly positive clones are often lost. This has been avoided by the process described in this paper, wherein, by combining the strategy of EBV transformation and recombinant DNA technology, we constructed human single chain variable fragments (scFvs against the third variable region (V3 of the clade C HIV-1 envelope. Results An antigen specific phage library of 7000 clones was constructed from the enriched V3- positive antibody secreting EBV transformed cells. By ligation of the digested scFv DNA into phagemid vector and bio panning against the HIV-1 consensus C and B V3 peptides followed by random selection of 40 clones, we identified 15 clones that showed V3 reactivity in phage ELISA. DNA fingerprinting analysis and sequencing showed that 13 out of the 15 clones were distinct. Expression of the positive clones was tested by SDS-PAGE and Western blot. All the 13 anti-V3 scFvs showed cross-reactivity against both the clade C and B V3 peptides and did not show any reactivity against other unrelated peptides in ELISA. Preliminary neutralization assays indicated varying degrees of neutralization of clade C and B viruses. EBV transformation, followed by antigen selection of lines to identify specific binders, enabled the selection of phage from un-cloned lines for scFv generation, thus avoiding the problems of hybridoma technology. Moreover, as the clones were pretested for antigen binding, a comparatively small library sufficed for the selection of a considerable number of unique antigen binding

HIV Viral Load

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... PF4 Antibody Hepatitis A Testing Hepatitis B Testing Hepatitis C Testing HER2/neu Herpes Testing High-sensitivity C-reactive Protein (hs-CRP) Histamine Histone Antibody HIV Antibody and HIV Antigen (p24) HIV Antiretroviral Drug Resistance Testing, Genotypic HIV Viral Load HLA Testing HLA- ...

The diagnosis of symptomatic acute antiretroviral syndrome during the window period with antigen/antibody testing and HIV viral load

Directory of Open Access Journals (Sweden)

Daniel O. Griffin

Full Text Available Despite much focus on moving toward a cure to end the epidemic human immunodeficiency virus (HIV epidemic there are still thousands of new infections occurring every year in the United States. Although there is ongoing transmission of HIV in the United States and a growing population of people living with HIV, the acute presentation of HIV infection can be challenging to diagnose and is often not considered when patients present to healthcare providers. Although in certain states there are HIV testing laws that require that all persons between the ages of 13 and 64 be offered HIV testing in an opt-out approach, many patient presenting with an acute illness, that would warrant diagnostic testing for HIV, leave without having an HIV test performed for either diagnostic or screening purposes.We describe the case of a woman who presented to medical attention with symptoms later confirmed to be due to acute HIV infection. She was initially discharged from the hospital and only underwent HIV testing with confirmation of her diagnosis after readmission. We describe the algorithm where fourth generation testing combined with HIV viral load testing allowed for the diagnosis of acute HIV prior to the development of a specific immunoglobulin response. Consideration of this diagnosis, improved HIV screening, and understanding of the use of antigen/antibody screening tests, combined with Multispot and HIV viral RNA detection, when appropriate, can allow for early diagnosis of HIV before progression of disease and before undiagnosed patient spread the infection to new contacts.

Productivity costs and determinants of productivity in HIV-infected patients.

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Sendi, Pedram; Schellenberg, Fabian; Ungsedhapand, Chaiwat; Kaufmann, Gilbert R; Bucher, Heiner C; Weber, Rainer; Battegay, Manuel

2004-05-01

In HIV-infected patients, reduced ability to work may be an important component of the societal costs of this disease. Few data about productivity costs in HIV-infected patients are available. The goals of this study were to estimate productivity costs in the HIV-infected population in Switzerland and to identify characteristics that may influence patient productivity. This cross-sectional study included all patients younger than retirement age (65 years for men and 62 years for women) who were enrolled in the Swiss HIV Cohort Study in 2002. Measures of productivity losses in this population were based on patients' ability to work and the median monthly wage rates adjusted for age, sex, and educational level in Switzerland. Factors associated with ability to work were analyzed in a multivariate ordinary logistic regression (proportional odds) model. As of July 1, 2002, the exchange rate for US dollars to Swiss francs (CHF) was US $1.00 approximately equal to CHF 1.48. A total of 5319 HIV-infected patients (3665 men [68.9%] and 1655 women [31.1%]; mean [SD] age, 40.6 [8.4] years; range, 17-64 years) were included in the study. The mean annual productivity loss per patient was estimated at CHF 22,910 (95% CI, CHF 22,064-CHF 23, 756). Ability to work was independently associated with the following (P increase: odds ratio [OR], 0.60 [95% CI, 0.54-0.62]), sex (female/male: OR, 0.73 [95% CI, 0.63-0.84]), history of IV drug use (OR, 0.22 [95% CI, 0.19-0.26]), time since first positive HIV test (>10 years vs or =501 vs 0-200 cells/microL: OR, 2.01 [95%, CI, 1.64-2.46]), history of AIDS-indicator disease (OR, 0.47 [95% CI, 0.41-0.55]), stable partnership during the last 6 months (OR, 1.63 [95% CI, 1.43-1.86]), and educational level (higher vs basic: OR, 1.68 [95% CI, 1.45-1.95]). Productivity losses to society for the HIV-infected population appeared to be substantial in this analysis. Given a patient's clinical health status, a higher education level and a stable

Alkaloidal glycosidase inhibitors (AGIs) as the cause of sporadic scrapie, and the potential treatment of both transmissible spongiform encephalopathies (TSEs) and human immunodeficiency virus (HIV) infection.

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Dealler, S

1994-02-01

AGIs are produced by plants and microorgansims in the environment. They are absorbed from the gut, distributed throughout the body and are concentrated inside cells. AGIs alter the glycan chains of cellular glycoproteins (CGP) during their formation so that the same CGP produced by different clones of cells (and hence with different glycan chains) becomes structurally the same. Prion protein (PrP), a CGP, is rendered indestructable to cellular mechanisms (as PrPi) by the TSE infective process; it is suggested that AGIs could both cause and prevent this by altering the primary structure of PrP. HIV envelope protein, gp120, carries glycan chains that are decided by the clone of the cells by which it is produced. Each cellular clone would be expected to add a specific group of glycan chains, making the gp120 antigenically separate. As HIV infection progresses, infected clone numbers rise, the antigenic diversity of gp120 may rise as would antibody production, trying to keep pace. Antigenically stimulated CD4+ cells carrying HIV genes, increase HIV production with gp120 antigenically different from its stimulant. AGIs prevent the glycan diversity and may prevent the extension of HIV infection.

IN VITRO STUDIES ON HEME OXYGENASE-1 AND P24 ANTIGEN HIV-1 LEVEL AFTERHYPERBARIC OXYGEN TREATMENTOFHIV-1 INFECTED ON PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS).

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Budiarti, Retno; Kuntaman; Nasronudin; Suryokusumo; Khairunisa, Siti Qamariyah

2018-01-01

Heme oxygenase-1 (HO-1) is a protein secreted by immune cells as a part of immune response mechanism.HO-1 can be induced by variety agents that causingoxidative stress, such as exposure to 100% oxygenat2,4 ATA pressure.It plays a vital role in maintaining cellular homeostasis.This study was conducted to identify the effect of hyperbaric oxygen exposure in cultured ofPBMCthat infected by HIV-1. Primary culture of PBMCs were isolated from 16 healthy volunteers and HIV-1 infected MT4 cell line by co-culture. The PBMCs were aliquoted into two wells as control group and treatment group. The 16 samples of HIV-1 infected PBMCwere exposed to oxygen at 2,4 ATA in animal hyperbaric chamber forthree times in 30 minutes periods with 5 minutes spacing period, that called 1 session.The Treatment done on 5 sessions within 5 days. 16 samples of HIV-1 infected PMBCs that have no hyperbaric treatment became control group.The supernatant were measured the HO-1 production by ELISA andmRNA expression of HO-1 by real time PCR and the number ofantigen p24 HIV-1by ELISA. The result showed that there was no increasing of HO-1 at both mRNA level and protein level, there was a decreasing number of antigen p24 HIV-1 at the treatment group. In addition, hyperbaric exposure could not increase the expression of HO-1, more over the viral replication might be reduced by other mechanism. Hyperbaric oxygen could increases cellular adaptive response of PBMCs infected HIV-1 through increased expression of proteins that can inhibit HIV viralreplication.

Performance comparison of the 4th generation Bio-Rad Laboratories GS HIV Combo Ag/Ab EIA on the EVOLIS™ automated system versus Abbott ARCHITECT HIV Ag/Ab Combo, Ortho Anti-HIV 1+2 EIA on Vitros ECi and Siemens HIV-1/O/2 enhanced on Advia Centaur.

Science.gov (United States)

Mitchell, Elizabeth O; Stewart, Greg; Bajzik, Olivier; Ferret, Mathieu; Bentsen, Christopher; Shriver, M Kathleen

2013-12-01

A multisite study was conducted to evaluate the performance of the Bio-Rad 4th generation GS HIV Combo Ag/Ab EIA versus Abbott 4th generation ARCHITECT HIV Ag/Ab Combo. The performance of two 3rd generation EIAs, Ortho Diagnostics Anti-HIV 1+2 EIA and Siemens HIV 1/O/2 was also evaluated. Study objective was comparison of analytical HIV-1 p24 antigen detection, sensitivity in HIV-1 seroconversion panels, specificity in blood donors and two HIV false reactive panels. Analytical sensitivity was evaluated with International HIV-1 p24 antigen standards, the AFFSAPS (pg/mL) and WHO 90/636 (IU/mL) standards; sensitivity in acute infection was compared on 55 seroconversion samples, and specificity was evaluated on 1000 negative blood donors and two false reactive panels. GS HIV Combo Ag/Ab demonstrated better analytical HIV antigen sensitivity compared to ARCHITECT HIV Ag/Ab Combo: 0.41 IU/mL versus 1.2 IU/mL (WHO) and 12.7 pg/mL versus 20.1 pg/mL (AFSSAPS); GS HIV Combo Ag/Ab EIA also demonstrated slightly better specificity compared to ARCHITECT HIV Ag/Ab Combo (100% versus 99.7%). The 4th generation HIV Combo tests detected seroconversion 7-11 days earlier than the 3rd generation HIV antibody only EIAs. Both 4th generation immunoassays demonstrated excellent performance in sensitivity, with the reduction of the serological window period (7-11 days earlier detection than the 3rd generation HIV tests). However, GS HIV Combo Ag/Ab demonstrated improved HIV antigen analytical sensitivity and slightly better specificity when compared to ARCHITECT HIV Ag/Ab Combo assay, with higher positive predictive values (PPV) for low prevalence populations. Copyright © 2013 Elsevier B.V. All rights reserved.

Enhancement of Human Antigen-Specific Memory T-Cell Responses by Interleukin-7 May Improve Accuracy in Diagnosing Tuberculosis▿ †

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Feske, Marsha; Nudelman, Rodolfo J.; Medina, Miguel; Lew, Justin; Singh, Manisha; Couturier, Jacob; Graviss, Edward A.; Lewis, Dorothy E.

2008-01-01

Children and immunocompromised adults are at an increased risk of tuberculosis (TB), but diagnosis is more challenging. Recently developed gamma interferon (IFN-γ) release assays provide increased sensitivity and specificity for diagnosis of latent TB, but their use is not FDA approved in immunocompromised or pediatric populations. Both populations have reduced numbers of T cells, which are major producers of IFN-γ. Interleukin 7 (IL-7), a survival cytokine, stabilizes IFN-γ message and increases protein production. IL-7 was added to antigen-stimulated lymphocytes to improve IFN-γ responses as measured by enzyme-linked immunosorbent assay (ELISA) and enzyme-linked immunospot (ELISPOT) assay. Antigens used were tetanus toxoid (n = 10), p24 (from human immunodeficiency virus [HIV], n = 9), and TB peptides (n = 15). Keyhole limpet hemocyanin was used as a negative control, and phytohemagglutinin was the positive control. IL-7 improved antigen-specific responses to all antigens tested including tetanus toxoid, HIV type 1 p24, and TB peptides (ESAT-6 and CFP-10) with up to a 14-fold increase (mean = 3.8), as measured by ELISA. Increased IFN-γ responses from controls, HIV-positive patients, and TB patients were statistically significant, with P values of <0.05, 0.01, and 0.05, respectively. ELISPOT assay results confirmed ELISA findings (P values of <0.01, 0.02, and 0.03, respectively), with a strong correlation between the two tests (R2 = 0.82 to 0.99). Based on average background levels, IL-7 increased detection of IFN-γ by 39% compared to the level with antigen alone. Increased production of IFN-γ induced by IL-7 improves sensitivity of ELISA and ELISPOT assays for all antigens tested. Further enhancement of IFN-γ-based assays might improve TB diagnosis in those populations at highest risk for TB. PMID:18753334

Antigen-Specific Interferon-Gamma Responses and Innate Cytokine Balance in TB-IRIS

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Goovaerts, Odin; Jennes, Wim; Massinga-Loembé, Marguerite; Ceulemans, Ann; Worodria, William; Mayanja-Kizza, Harriet; Colebunders, Robert; Kestens, Luc

2014-01-01

Background Tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) remains a poorly understood complication in HIV-TB patients receiving antiretroviral therapy (ART). TB-IRIS could be associated with an exaggerated immune response to TB-antigens. We compared the recovery of IFNγ responses to recall and TB-antigens and explored in vitro innate cytokine production in TB-IRIS patients. Methods In a prospective cohort study of HIV-TB co-infected patients treated for TB before ART initiation, we compared 18 patients who developed TB-IRIS with 18 non-IRIS controls matched for age, sex and CD4 count. We analyzed IFNγ ELISpot responses to CMV, influenza, TB and LPS before ART and during TB-IRIS. CMV and LPS stimulated ELISpot supernatants were subsequently evaluated for production of IL-12p70, IL-6, TNFα and IL-10 by Luminex. Results Before ART, all responses were similar between TB-IRIS patients and non-IRIS controls. During TB-IRIS, IFNγ responses to TB and influenza antigens were comparable between TB-IRIS patients and non-IRIS controls, but responses to CMV and LPS remained significantly lower in TB-IRIS patients. Production of innate cytokines was similar between TB-IRIS patients and non-IRIS controls. However, upon LPS stimulation, IL-6/IL-10 and TNFα/IL-10 ratios were increased in TB-IRIS patients compared to non-IRIS controls. Conclusion TB-IRIS patients did not display excessive IFNγ responses to TB-antigens. In contrast, the reconstitution of CMV and LPS responses was delayed in the TB-IRIS group. For LPS, this was linked with a pro-inflammatory shift in the innate cytokine balance. These data are in support of a prominent role of the innate immune system in TB-IRIS. PMID:25415590

Cerebrospinal fluid HIV-1 RNA levels in asymptomatic patients with early stage chronic HIV-1 infection: support for the hypothesis of local virus replication.

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García, F; Niebla, G; Romeu, J; Vidal, C; Plana, M; Ortega, M; Ruiz, L; Gallart, T; Clotet, B; Miró, J M; Pumarola, T; Gatell, J M

1999-08-20

To assess HIV-1 RNA levels in cerebrospinal fluid (CSF) and their potential correlation with plasma viral load and central nervous system (CNS) HIV-1 infection markers in stable asymptomatic patients with a CD4 T cell count >500x10(6) cells/l. Consecutive patients screened for two trials were eligible for lumbar puncture assessment. At day 0, simultaneous samples of CSF and plasma were obtained and levels of total proteins, albumin, IgG, antibodies against HIV-1 p24 antigen, HIV-1 RNA (using the polymerase chain technique) and white cells were measured. The integrity of the blood-brain barrier was preserved (albumin index > or =7) in 59 out of 70 patients (84%). Intrathecal production of antibodies against HIV-1 p24 antigen was demonstrated in 55 out of 70 individuals (78%). Viral load in CSF was significantly lower than plasma values (3.13+/-0.95 versus 4.53+/-0.53, P = 0.0001). HIV-1 RNA was not detected in CSF in only three of the 70 patients (4%). Overall, there was a significant correlation between plasma and CSF HIV-1 RNA levels (r = 0.43, P = 0.0001); however, in 29 patients (41%) there were significant differences (>1.5 log10 copies/ml) between the viral loads in plasma and CSF. In the multivariate analysis, a high level of protein and white cells in CSF, but not the HIV-1 RNA plasma level, were factors independently associated with a higher level of HIV-1 RNA in CSF (P = 0.0001). HIV-1 RNA can be detected almost always in CSF of asymptomatic patients in early stages of HIV-1 infection including those with a preserved integrity of the blood-brain barrier. The important discrepancies between plasma and CSF viral load, and the independent association between CSF abnormalities and CSF viral load, support the hypothesis of local production of HIV-1.

Immunogenicity in pig-tailed macaques of poliovirus replicons expressing HIV-1 and SIV antigens and protection against SHIV-89.6P disease

International Nuclear Information System (INIS)

Fultz, Patricia N.; Stallworth, Jackie; Porter, Donna; Novak, Miroslav; Anderson, Marie J.; Morrow, Casey D.

2003-01-01

In the search for an effective vaccine against the human immunodeficiency virus (HIV), novel ways to deliver viral antigens are being evaluated. One such approach is the use of nonreplicating viral vectors encoding HIV and/or SIV genes that are expressed after infection of host cells. Nonreplicating poliovirus vectors, termed replicons, that expressed HIV-1/HXB2 and SIVmac239 gag and various HIV-1 env genes from different clades were tested for immunogenicity and protective efficacy against intravenous challenge of pig-tailed macaques with SHIV-89.6P. To maximize both cellular and humoral immune responses, a prime-boost regimen was used. Initially, macaques were immunized four times over 35 weeks by either the intranasal and intrarectal or the intramuscular (im) route with mixtures of poliovirus replicons expressing HIV-1 gag and multiple env genes. Immunization with replicons alone induced both serum antibodies and lymphocyte proliferative responses. After boosting with purified Env protein, neutralizing antibodies to SHIV-89.6P were induced in four of five immunized animals. In a second experiment, four macaques were immunized im three times over 27 weeks with replicons expressing the SIVmac239 gag and HIV-1/HXB2 env genes. All immunized animals were then boosted twice with purified HIV-1-89.6 rgp140-Env and SIVmac239 p55-Gag proteins. Four control animals received only the two protein inoculations. Immunized and control animals were then challenged intravenously with the pathogenic SHIV-89.6P. After challenge the animals were monitored for virus isolation from peripheral blood mononuclear cells and plasma viremia and for changes in virus-specific antibody titers. Naieve pig-tailed macaques experienced rapid loss of CD4 + T cells and died between 38 and 62 weeks after infection. In contrast, macaques immunized with replicons and proteins rapidly cleared plasma virus and did not experience sustained loss of CD4 + lymphocytes. Furthermore, two of the four macaques

Effect of isoprinosine on HIV antigenaemia

DEFF Research Database (Denmark)

Teglbjærg, Lars Stubbe; Kroon, S; Sandström, E

1992-01-01

OBJECTIVE: The objective of this study was to evaluate the effect of isoprinosine on HIV-antigen expression in HIV-positive patients without AIDS. DESIGN: Serum samples from anti-HIV-positive patients without AIDS participating in a double-blind, placebo-controlled trial of isoprinosine...... in the treatment of HIV infection were analysed for the presence of HIV antigen. SETTING: Data and samples were collected from the 21 medical centres who participated in the Scandinavian multicentre placebo-controlled isoprinosine study. PATIENTS, PARTICIPANTS: Samples were available from 19 of 21 participating...... centres. Of 866 patients who enrolled, baseline serum samples were available for 642 (74%; 308 isoprinosine- and 334 placebo-treated patients). INTERVENTIONS: Treatment was 1 g isoprinosine administered orally three times a day or matching placebo for 24 weeks. MAIN OUTCOME MEASURES: Comparison of HIV...

[Detecting the markers of HIV infection with the new enzyme immunoassay diagnostic kit "DS-EIA-HIV-AB-AG-SPECTRUM" at the laboratories of AIDS prevention and control centers in the Volga Federal District].

Science.gov (United States)

Ivanova, N I; Peksheva, O Iu

2009-03-01

A possibility of simultaneously detecting specific antibodies to HIV-1 and HIV-2 by enzyme immunoassay (EIA) at lower concentrations than those by immunoblotting (IB), and well as an additional possibility of earlier diagnosis of HIV infection, by identifying the HIV-1 antigen p24 lay the foundation of the "DS-EIA-HIV-AB-AG-SPECTRUM" test system made by OOO "Research-and-Production Association "Diagnosticheskiye Sistemy" (Diagnostic Systems). These peculiarities were compared with those of IB at a number of laboratories of AIDS prevention and control centers in the Volga Federal District, by using native serum/plasma samples and a specially designed control panel. The analysis of the conducted studies to identify HIV-1 and HIV-2 antibodies and HIV-1 antigen p24 in 65 plasma/serum samples in the "DS-EIA-HIV-AB-AG-SPECTRUM" and "LIA-HIV-1/2" (OOO "Niarmedik plus") test systems while confirming the positive result indicated agreement in 57 (87.7%) cases. The diagnostic possibilities of the "DS-EIA-HIV-AB-AG-SPECTRUM" test system versus the "New Lav-Blot I" one to make a laboratory diagnosis of HIV infection were studied. Irrefragable answers as to the availability of HIV-1 markers in the study serum samples on the enciphered panel were provided by IB in 73.3% of cases and EIA in 92%.

HIV-1 isolation from infected peripheral blood mononuclear cells.

Science.gov (United States)

Dispinseri, Stefania; Saba, Elisa; Vicenzi, Elisa; Kootstra, Neeltje A; Schuitemaker, Hanneke; Scarlatti, Gabriella

2014-01-01

Human immunodeficiency virus 1 (HIV-1) isolation from peripheral blood mononuclear cells (PBMCs) allows retrieval of replication-competent viral variants. In order to impose the smallest possible selective pressure on the viral isolates, isolation must be carried out in primary cultures of cells and not in tumor derived cell lines. The procedure involves culture of PBMCs from an infected patient with phytohemagglutinin (PHA)-stimulated PBMC from seronegative donors, which provide susceptible target cells for HIV replication. HIV can be isolated from the bulk population of PBMCs or after cloning of the cells to obtain viral biological clones. Viral production is determined with p24 antigen (Ag) detection assays or with reverse transcriptase (RT) activity assay. Once isolated, HIV-1 can be propagated by infecting PHA-stimulated PBMCs from healthy donors. Aliquots from culture with a high production of virus are stored for later use.

Predictive value of prostate-specific antigen for prostate cancer

DEFF Research Database (Denmark)

Shepherd, Leah; Borges, Alvaro Humberto; Ravn, Lene

2014-01-01

INTRODUCTION: Although prostate cancer (PCa) incidence is lower in HIV+ men than in HIV- men, the usefulness of prostate-specific antigen (PSA) screening in this population is not well defined and may have higher false negative rates than in HIV- men. We aimed to describe the kinetics and predict......INTRODUCTION: Although prostate cancer (PCa) incidence is lower in HIV+ men than in HIV- men, the usefulness of prostate-specific antigen (PSA) screening in this population is not well defined and may have higher false negative rates than in HIV- men. We aimed to describe the kinetics...... and predictive value of PSA in HIV+ men. METHODS: Men with PCa (n=21) and up to two matched controls (n=40) with prospectively stored plasma samples before PCa (or matched date in controls) were selected. Cases and controls were matched on date of first and last sample, age, region of residence and CD4 count...... at first sample date. Total PSA (tPSA), free PSA (fPSA), testosterone and sex hormone binding globulin (SHBG) were measured. Conditional logistic regression models investigated associations between markers and PCa. Sensitivity and specificity of using tPSA >4 µg/L to predict PCa was calculated. Mixed...

Rapid production of antigen-specific monoclonal antibodies from a variety of animals

Directory of Open Access Journals (Sweden)

Kurosawa Nobuyuki

2012-09-01

Full Text Available Abstract Background Although a variety of animals have been used to produce polyclonal antibodies against antigens, the production of antigen-specific monoclonal antibodies from animals remains challenging. Results We propose a simple and rapid strategy to produce monoclonal antibodies from a variety of animals. By staining lymph node cells with an antibody against immunoglobulin and a fluorescent dye specific for the endoplasmic reticulum, plasma/plasmablast cells were identified without using a series of antibodies against lineage markers. By using a fluorescently labeled antigen as a tag for a complementary cell surface immunoglobulin, antigen-specific plasma/plasmablast cells were sorted from the rest of the cell population by fluorescence-activated cell sorting. Amplification of cognate pairs of immunoglobulin heavy and light chain genes followed by DNA transfection into 293FT cells resulted in the highly efficient production of antigen-specific monoclonal antibodies from a variety of immunized animals. Conclusions Our technology eliminates the need for both cell propagation and screening processes, offering a significant advantage over hybridoma and display strategies.

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

Impact of aging and HIV infection on serologic response to seasonal influenza vaccination.

Science.gov (United States)

Pallikkuth, Suresh; De Armas, Lesley R; Pahwa, Rajendra; Rinaldi, Stefano; George, Varghese K; Sanchez, Celeste M; Pan, Li; Dickinson, Gordon; Rodriguez, Allan; Fischl, Margaret; Alcaide, Maria; Pahwa, Savita

2018-02-08

To determine influence of age and HIV infection on influenza vaccine responses. Evaluate serologic response to seasonal trivalent influenza vaccine (TIV) as the immunologic outcome in HIV-infected (HIV) and age-matched HIV negative (HIV) adults. During 2013-2016, 151 virologically controlled HIV individuals on antiretroviral therapy and 164 HIV volunteers grouped by age as young (<40 years), middle aged (40-59 years) and old (≥60 years) were administered TIV and investigated for serum antibody response to vaccine antigens. At prevaccination (T0) titers were in seroprotective range in more than 90% of participants. Antibody titers increased in all participants postvaccination but frequency of classified vaccine responders to individual or all three vaccine antigens at 3-4 weeks was higher in HIV than HIV adults with the greatest differences manifesting in the young age group. Of the three vaccine strains in TIV, antibody responses at T2 were weakest against H3N2 with those to H1N1 and B antigens dominating. Among the age groups, the titers for H1N1 and B were lowest in old age, with evidence of an age-associated interaction in HIV persons with antibody to B antigen. Greater frequencies of vaccine nonresponders are seen in HIV young compared with HIV adults and the observed age-associated interaction for B antigen in HIV persons are supportive of the concept of premature immune senescence in controlled HIV infection. High-potency influenza vaccination recommended for healthy aging could be considered for HIV adults of all ages.

Production of prostate-specific antigen by a breast cancer cell line, Sk-Br-3

International Nuclear Information System (INIS)

Kamali Sarvestani, E.; Ghaderi, A.

2002-01-01

Prostate-specific antigen is a 33-KDa serine protease that is produced predominantly by prostate epithelium. However, it has been shown that about 30-40% of female breast tumors produce prostate-specific antigen and its production is associated with the presence of estrogen and progesterone receptors. We have now developed a new tissue culture system to study prostate-specific antigen production in breast cancer and its association with prognostic factors such as progesterone receptor and c-erbB-2. For this purpose we investigated the ability of prostate-specific antigen production in five different cell lines, including two breast cancer cell lines, Sk-Br-3 and MDA-MB-453. The prostate-specific antigen in tissue culture supernatant and cytoplasm of the Sk-Br-3 cell line was detected by western blotting and immunoperoxidase, respectively. Furthermore, we found lower expression of c-erbB-2 in Sk-Br-3 than non-prostate-specific antigen producer breast cancer cell line, MDA-MB-453. Progesterone receptor was expressed by both prostate-specific antigen-positive and -negative cell lines and only the intensity of staining and the number of positive cells in Sk-Br-3 population was higher than MDA-MB-453. According to our findings prostate-specific antigen can be considered as a good prognostic factor in breast cancer and we suggest that these two cell lines are a good in vitro model to study the relationship of different breast cancer prognostic factors and their regulations

Systemic activation of the immune system in HIV infection: The role of the immune complexes (hypothesis).

Science.gov (United States)

Korolevskaya, Larisa B; Shmagel, Konstantin V; Shmagel, Nadezhda G; Saidakova, Evgeniya V

2016-03-01

Currently, immune activation is proven to be the basis for the HIV infection pathogenesis and a strong predictor of the disease progression. Among the causes of systemic immune activation the virus and its products, related infectious agents, pro-inflammatory cytokines, and regulatory CD4+ T cells' decrease are considered. Recently microbial translocation (bacterial products yield into the bloodstream as a result of the gastrointestinal tract mucosal barrier integrity damage) became the most popular hypothesis. Previously, we have found an association between immune complexes present in the bloodstream of HIV infected patients and the T cell activation. On this basis, we propose a significantly modified hypothesis of immune activation in HIV infection. It is based on the immune complexes' participation in the immunocompetent cells' activation. Immune complexes are continuously formed in the chronic phase of the infection. Together with TLR-ligands (viral antigens, bacterial products coming from the damaged gut) present in the bloodstream they interact with macrophages. As a result macrophages are transformed into the type II activated forms. These macrophages block IL-12 production and start synthesizing IL-10. High level of this cytokine slows down the development of the full-scale Th1-response. The anti-viral reactions are shifted towards the serogenesis. Newly synthesized antibodies' binding to viral antigens leads to continuous formation of the immune complexes capable of interacting with antigen-presenting cells. Copyright © 2016 Elsevier Ltd. All rights reserved.

Antigenic analyses of tissues and excretory and secretory products from Strongylus vulgaris.

OpenAIRE

Wynne, E; Slocombe, J O; Wilkie, B N

1981-01-01

Rabbit antisera were prepared against veronal buffered saline extracts of L4 and L5 Strongylus vulgaris, adult S. vulgaris and adult Strongylus equinus retrieved from naturally infected horses. In agar gel diffusion with these antisera, adult S vulgaris and S. equinus each appeared to have at least one unique antigen; larval S. vulgaris appeared to have two species-specific and two stage-specific antigens. There were several common antigens. Excretory and secretory products were collected als...

Hiv/hbv, hiv/hcv and hiv/htlv-1 co infection among injecting drug user patients hospitalized at the infectious disease ward of a training hospital in iran

International Nuclear Information System (INIS)

Alavi, S.M.; Etemadi, A.

2007-01-01

To assess the prevalence and risk factors for HBV, HCV and HTLV-I co-infection in the Iranian HIV positive Injecting Drug Users (IDU) patients admitted in hospital. Analyses were based on 154 male IDU patients admitted in Infectious disease ward of Razi Hospital, Ahwaz, Iran, from April 2001 to March 2003. All of them had been tested for HIV infection (Elisa-antibody and Western blot), HBV surface antigen, HCV antibody and HTLV-1 antibody. One hundred and four patients (67.53%) were identified as HIV infected. Among HIV infected, HB surface antigen, HCV antibody and HTLV-I antibody were positive in 44.23% and 74.04% and 16.33% patients respectively. HCV/HBV/HIV and HCV/HBV/HIV/HTLV-1 co-infection were 20.20% and 8.65% respectively. Co-infection with HBV or HCV or HTLV-1 is common among hospitalized HIV-infected IDU patients in the region of study. HIV disease outcomes appear to be adversely affected by HBV/HCV/HTLV-I co-infection, so identification of these viral infections is recommended as routine tests for this population. (author)

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

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Kwan-Ki Hwang

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

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.

Vaginal Prostate Specific Antigen (PSA) Is a Useful Biomarker of Semen Exposure Among HIV-Infected Ugandan Women.

Science.gov (United States)

Woolf-King, Sarah E; Muyindike, Winnie; Hobbs, Marcia M; Kusasira, Adrine; Fatch, Robin; Emenyonu, Nneka; Johnson, Mallory O; Hahn, Judith A

2017-07-01

The practical feasibility of using prostate specific antigen (PSA) as a biomarker of semen exposure was examined among HIV-infected Ugandan women. Vaginal fluids were obtained with self-collected swabs and a qualitative rapid test (ABAcard ® p30) was used to detect PSA. Trained laboratory technicians processed samples on-site and positive PSA tests were compared to self-reported unprotected vaginal sex (UVS) in the last 48 h. A total of 77 women submitted 126 samples for PSA testing at up to three study visits. Of these samples, 31 % (n = 39/126) were PSA positive, and 64 % (n = 25/39) of the positive PSA samples were accompanied by self-report of no UVS at the study visit the PSA was collected. There were no reported difficulties with specimen collection, storage, or processing. These findings provide preliminary data on high levels of misreported UVS among HIV-infected Ugandan women using practically feasible methods for PSA collection and processing.

Variable processing and cross-presentation of HIV by dendritic cells and macrophages shapes CTL immunodominance and immune escape.

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Jens Dinter

2015-03-01

Full Text Available Dendritic cells (DCs and macrophages (Møs internalize and process exogenous HIV-derived antigens for cross-presentation by MHC-I to cytotoxic CD8⁺ T cells (CTL. However, how degradation patterns of HIV antigens in the cross-presentation pathways affect immunodominance and immune escape is poorly defined. Here, we studied the processing and cross-presentation of dominant and subdominant HIV-1 Gag-derived epitopes and HLA-restricted mutants by monocyte-derived DCs and Møs. The cross-presentation of HIV proteins by both DCs and Møs led to higher CTL responses specific for immunodominant epitopes. The low CTL responses to subdominant epitopes were increased by pretreatment of target cells with peptidase inhibitors, suggestive of higher intracellular degradation of the corresponding peptides. Using DC and Mø cell extracts as a source of cytosolic, endosomal or lysosomal proteases to degrade long HIV peptides, we identified by mass spectrometry cell-specific and compartment-specific degradation patterns, which favored the production of peptides containing immunodominant epitopes in all compartments. The intracellular stability of optimal HIV-1 epitopes prior to loading onto MHC was highly variable and sequence-dependent in all compartments, and followed CTL hierarchy with immunodominant epitopes presenting higher stability rates. Common HLA-associated mutations in a dominant epitope appearing during acute HIV infection modified the degradation patterns of long HIV peptides, reduced intracellular stability and epitope production in cross-presentation-competent cell compartments, showing that impaired epitope production in the cross-presentation pathway contributes to immune escape. These findings highlight the contribution of degradation patterns in the cross-presentation pathway to HIV immunodominance and provide the first demonstration of immune escape affecting epitope cross-presentation.

Prognostic value of immunologic abnormalities and HIV antigenemia in asymptomatic HIV-infected individuals: proposal of immunologic staging

DEFF Research Database (Denmark)

Hofmann, B; Bygbjerg, Ib Christian; Dickmeiss, E

1989-01-01

The prognostic value of various immunologic tests was investigated in 150 HIV-seropositive homosexual men, who were initially without HIV-related symptoms or AIDS and who were followed for a median of 12 months (range 3-28 months). The laboratory investigations included HIV antigen in serum, total...... lymphocyte count, T-helper (CD4) and T-cytotoxic/suppressor (CD8) counts, and lymphocyte transformation responses to the mitogens phytohemagglutinin (PHA) and pokeweed mitogen (PWM), and to antigenic extracts from Candida albicans and cytomegalovirus. 24 individuals developed HIV-related symptoms or AIDS (11...... cases). All parameters except the CD8 count were of prognostic value, but a multivariate analysis of symptom-free survival showed that HIV antigenemia, a CD4 count less than 0.5 x 10(9)/l, and relative response to PWM below 25% of controls contained all the prognostic information. Individuals abnormal...

High throughput production of mouse monoclonal antibodies using antigen microarrays

DEFF Research Database (Denmark)

De Masi, Federico; Chiarella, P.; Wilhelm, H.

2005-01-01

Recent advances in proteomics research underscore the increasing need for high-affinity monoclonal antibodies, which are still generated with lengthy, low-throughput antibody production techniques. Here we present a semi-automated, high-throughput method of hybridoma generation and identification....... Monoclonal antibodies were raised to different targets in single batch runs of 6-10 wk using multiplexed immunisations, automated fusion and cell-culture, and a novel antigen-coated microarray-screening assay. In a large-scale experiment, where eight mice were immunized with ten antigens each, we generated...

Association between Hlaantigens and Progression of HIV Infection in Greek Haemophiliacs

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Chr. Papasteriades

1993-01-01

Full Text Available The frequencies of HLA antigens in 33 HIV seronegative and in 88 HIV seropositive haemophiliacs, who have been followed for at least 6 years since seroconversion or first HIV positive test. were evaluated in relation to disease susceptibility and disease progression. A high frequency of HLA-A2 and -DR2 antigens and a low frequency of HLA-A9 were found to characterize HIV seropositive patients (p<0.05. Progressors to symptomatic CDC stage IV had a higher frequency of HLA-A9 (p<0.01 and DR3. Rapid decline of CD4+ T cells in these patients was associated with HLA-A9, -DR I and DR3. Our data suggest that HLA antigens may contribute to susceptibility to HIV infection and disease progression in Greek haemophiliacs.

Dendritic cells exposed to MVA-based HIV-1 vaccine induce highly functional HIV-1-specific CD8(+ T cell responses in HIV-1-infected individuals.

Directory of Open Access Journals (Sweden)

Núria Climent

Full Text Available Currently, MVA virus vectors carrying HIV-1 genes are being developed as HIV-1/AIDS prophylactic/therapeutic vaccines. Nevertheless, little is known about the impact of these vectors on human dendritic cells (DC and their capacity to present HIV-1 antigens to human HIV-specific T cells. This study aimed to characterize the interaction of MVA and MVA expressing the HIV-1 genes Env-Gag-Pol-Nef of clade B (referred to as MVA-B in human monocyte-derived dendritic cells (MDDC and the subsequent processes of HIV-1 antigen presentation and activation of memory HIV-1-specific T lymphocytes. For these purposes, we performed ex vivo assays with MDDC and autologous lymphocytes from asymptomatic HIV-infected patients. Infection of MDDC with MVA-B or MVA, at the optimal dose of 0.3 PFU/MDDC, induced by itself a moderate degree of maturation of MDDC, involving secretion of cytokines and chemokines (IL1-ra, IL-7, TNF-α, IL-6, IL-12, IL-15, IL-8, MCP-1, MIP-1α, MIP-1β, RANTES, IP-10, MIG, and IFN-α. MDDC infected with MVA or MVA-B and following a period of 48 h or 72 h of maturation were able to migrate toward CCL19 or CCL21 chemokine gradients. MVA-B infection induced apoptosis of the infected cells and the resulting apoptotic bodies were engulfed by the uninfected MDDC, which cross-presented HIV-1 antigens to autologous CD8(+ T lymphocytes. MVA-B-infected MDDC co-cultured with autologous T lymphocytes induced a highly functional HIV-specific CD8(+ T cell response including proliferation, secretion of IFN-γ, IL-2, TNF-α, MIP-1β, MIP-1α, RANTES and IL-6, and strong cytotoxic activity against autologous HIV-1-infected CD4(+ T lymphocytes. These results evidence the adjuvant role of the vector itself (MVA and support the clinical development of prophylactic and therapeutic anti-HIV vaccines based on MVA-B.

The involvement of plasmacytoid cells in HIV infection and pathogenesis.

Science.gov (United States)

Aiello, Alessandra; Giannessi, Flavia; Percario, Zulema A; Affabris, Elisabetta

2018-04-01

Plasmacytoid dendritic cells (pDCs) are a unique dendritic cell subset that are specialized in type I interferon (IFN) production. pDCs are key players in the antiviral immune response and serve as bridge between innate and adaptive immunity. Although pDCs do not represent the main reservoir of the Human Immunodeficiency Virus (HIV), they are a crucial subset in HIV infection as they influence viral transmission, target cell infection and antigen presentation. pDCs act as inflammatory and immunosuppressive cells, thus contributing to HIV disease progression. This review provides a state of art analysis of the interactions between HIV and pDCs and their potential roles in HIV transmission, chronic immune activation and immunosuppression. A thorough understanding of the roles of pDCs in HIV infection will help to improve therapeutic strategies to fight HIV infection, and will further increase our knowledge on this important immune cell subset. Copyright © 2018 Elsevier Ltd. All rights reserved.

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.

Antigen-driven C–C Chemokine-mediated HIV-1 Suppression by CD4+ T Cells from Exposed Uninfected Individuals Expressing the Wild-type CCR-5 Allele

Science.gov (United States)

Furci, Lucinda; Scarlatti, Gabriella; Burastero, Samuele; Tambussi, Giuseppe; Colognesi, Claudia; Quillent, Caroline; Longhi, Renato; Loverro, Patrizia; Borgonovo, Barbara; Gaffi, Davide; Carrow, Emily; Malnati, Mauro; Lusso, Paolo; Siccardi, Antonio G.; Lazzarin, Adriano; Beretta, Alberto

1997-01-01

Despite repeated exposure to HIV-1, certain individuals remain persistently uninfected. Such exposed uninfected (EU) people show evidence of HIV-1–specific T cell immunity and, in rare cases, selective resistance to infection by macrophage-tropic strains of HIV-1. The latter has been associated with a 32–base pair deletion in the C–C chemokine receptor gene CCR-5, the major coreceptor of macrophage-tropic strains of HIV-1. We have undertaken an analysis of the HIV-specific T cell responses in 12 EU individuals who were either homozygous for the wild-type CCR-5 allele or heterozygous for the deletion allele (CCR-5Δ32). We have found evidence of an oligoclonal T cell response mediated by helper T cells specific for a conserved region of the HIV-1 envelope. These cells produce very high levels of C–C chemokines when stimulated by the specific antigen and suppress selectively the replication of macrophage-tropic, but not T cell–tropic, strains of HIV-1. These chemokine-producing helper cells may be part of a protective immune response that could be potentially exploited for vaccine development. PMID:9236198

Abnormal antigens in breast cancer tissues and production of monoclonal antibodies against one of these antigens

Energy Technology Data Exchange (ETDEWEB)

Mohammed, M E. A. [University of Khartoum, Khartoum (Sudan)

2010-02-15

Breast cancer is associated with up regulation, down regulation of normal antigens or abnormal antigens. These antigens are very useful candidates as targets for the different breast cancer therapies and for vaccination trials. This study was done to characterize abnormal antigens, extract one of them and to produce monoclonal antibodies against the extracted antigen. One hundred and twenty Sudanese female patients were included in this study after informed consent. The mean age was 47. 2 years (16-80). Two tissue samples were obtained from each patient and they were confirmed as normal and cancerous breast tissues microscopically. 2D PAGE was used to analyze the protein content of samples. LC/MS and nr. fast a database search were used for separation and indentification of the abnormal proteins. Three different patterns of 2D Page results were obtained, the first pattern involved detection of four abnormal proteins in 26.7% of the patient cancerous tissues while they were undetected in the normal tissues of the same patients. In the second 2D PAGE result pattern the cancerous and the normal tissues of 67.5% patients were identical and they did not contain the four abnormal proteins while the third 2D PAGE pattern involved the presence of two abnormal antigens (from the four) in the cancerous tissues of 5.8% of the patients and they were absent from the normal tissues of the same patients. The four abnormal proteins were identified as, human Thioredoxin (D60nmutant), x-ray crystal structure of human galectin-1, retrocopy of tropomyosin 3(rc TPM3) and beta-tropomyosin (isoform 2). The primary and the secondary structures were obtained from the SWISSPROT and the PDB databases. Beta tropomyosin spot was extracted and used as antigen for monoclonal antibody production. Monoclonal antibody against beta- tropomyosin with a concentration of 0.35 mg/ml and a G11 anti beta-tropomyosin hybridoma cell line were produced. The monoclonal antibody was with single bad and

Abnormal antigens in breast cancer tissues and production of monoclonal antibodies against one of these antigens

International Nuclear Information System (INIS)

Mohammed, M. E. A.

2010-02-01

Breast cancer is associated with up regulation, down regulation of normal antigens or abnormal antigens. These antigens are very useful candidates as targets for the different breast cancer therapies and for vaccination trials. This study was done to characterize abnormal antigens, extract one of them and to produce monoclonal antibodies against the extracted antigen. One hundred and twenty Sudanese female patients were included in this study after informed consent. The mean age was 47. 2 years (16-80). Two tissue samples were obtained from each patient and they were confirmed as normal and cancerous breast tissues microscopically. 2D PAGE was used to analyze the protein content of samples. LC/MS and nr. fast a database search were used for separation and indentification of the abnormal proteins. Three different patterns of 2D Page results were obtained, the first pattern involved detection of four abnormal proteins in 26.7% of the patient cancerous tissues while they were undetected in the normal tissues of the same patients. In the second 2D PAGE result pattern the cancerous and the normal tissues of 67.5% patients were identical and they did not contain the four abnormal proteins while the third 2D PAGE pattern involved the presence of two abnormal antigens (from the four) in the cancerous tissues of 5.8% of the patients and they were absent from the normal tissues of the same patients. The four abnormal proteins were identified as, human Thioredoxin (D60nmutant), x-ray crystal structure of human galectin-1, retrocopy of tropomyosin 3(rc TPM3) and beta-tropomyosin (isoform 2). The primary and the secondary structures were obtained from the SWISSPROT and the PDB databases. Beta tropomyosin spot was extracted and used as antigen for monoclonal antibody production. Monoclonal antibody against beta- tropomyosin with a concentration of 0.35 mg/ml and a G11 anti beta-tropomyosin hybridoma cell line were produced. The monoclonal antibody was with single bad and

Clinical presentation and opportunistic infections in HIV-1, HIV-2 and HIV-1/2 dual seropositive patients in Guinea-Bissau

DEFF Research Database (Denmark)

Sørensen, Allan; Jespersen, Sanne; Katzenstein, Terese L

2016-01-01

HIV-2 is prevalent. In this study, we aimed to characterize the clinical presentations among HIV-1, HIV-2 and HIV-1/2 dual seropositive patients. Methods: In a cross-sectional study, newly diagnosed HIV patients attending the HIV outpatient clinic at Hospital Nacional Sim~ao Mendes in Guinea......-Bissau were enrolled. Demographical and clinical data were collected and compared between HIV-1, HIV-2 and HIV-1/2 dual seropositive patients. Results: A total of 169 patients (76% HIV-1, 17% HIV-2 and 6% HIV 1/2) were included in the study between 21 March 2012 and 14 December 2012. HIV-1 seropositive...... antigen. Conclusion: HIV-1 and HIV-1/2 seropositive patients have lower CD4 cell counts than HIV-2 seropositive patients when diagnosed with HIV with only minor clinical and demographic differences among groups. Few patients were diagnosed with TB and cryptococcal disease was not found to be a major...

Immunoregulatory activities of human immunodeficiency virus (HIV) proteins: Effect of HIV recombinant and synthetic peptides on immunoglobulin synthesis and proliferative responses by normal lymphocytes

International Nuclear Information System (INIS)

Nair, M.P.N.; Pottathil, R.; Heimer, E.P.; Schwartz, S.A.

1988-01-01

Recombinant and synthetic peptides corresponding to envelope proteins of the human immunodeficiency virus (HIV) were examined for their effects on the activities of lymphocytes from normal donors in vitro. Although lymphocytes cultured with env-gag peptides produced significant amounts of IgG, addition of env-gag peptides to a pokeweed mitogen-induced B-cell activation system resulted in suppression of immunoglobulin synthesis by normal lymphocytes. Recombinant antigens, env-gag and env-80 dihydrofolate reductase (DHFR), produced a substantial proliferative response by peripheral blood mononuclear cells (PBMC) as determined by [ 3 H]thymidine incorporation. PBMC precultured with HIV synthetic peptide env 578-608 also manifested significant proliferative responses as compared to control cultures. CD3 + lymphocytes precultured with recombinant HIV antigens, env-gag and env-80 DHFR, and synthetic HIV peptide, env 487-511, showed moderate but significant proliferative responses. Both recombinant antigens and synthetic peptides also produced a dose-dependent stimulatory effect on proliferation by CD3 - lymphocytes. These studies demonstrate that recombinant and synthetic peptides of the HIV genome express immunoregulatory T- and B-cell epitopes. Identification of unique HIV epitopes with immunogenic and immunoregulatory activities is necessary for the development of an effective vaccine against HIV infection

Asymptomatic cryptococcal antigen prevalence detected by lateral flow assay in hospitalised HIV-infected patients in São Paulo, Brazil.

Science.gov (United States)

Vidal, José E; Toniolo, Carolina; Paulino, Adriana; Colombo, Arnaldo; Dos Anjos Martins, Marilena; da Silva Meira, Cristina; Pereira-Chioccola, Vera Lucia; Figueiredo-Mello, Claudia; Barros, Tiago; Duarte, Jequelie; Fonseca, Fernanda; Alves Cunha, Mirella; Mendes, Clara; Ribero, Taiana; Dos Santos Lazera, Marcia; Rajasingham, Radha; Boulware, David R

2016-12-01

To determine the prevalence of asymptomatic cryptococcal antigen (CRAG) using lateral flow assay (LFA) in hospitalised HIV-infected patients with CD4 counts 18 years old without prior cryptococcal meningitis, without clinical suspicion of cryptococcal meningitis, regardless of antiretroviral (ART) status, and with CD4 counts <200 cells/μl. Serum CRAG was tested by LFA in all patients, and whole blood CRAG was tested by LFA in positive cases. We enrolled 163 participants of whom 61% were men. The duration of HIV diagnosis was a median of 8 (range, 1-29) years. 26% were antiretroviral (ART)-naïve, and 74% were ART-experienced. The median CD4 cell count was 25 (range, 1-192) cells/μl. Five patients (3.1%; 95%CI, 1.0-7.0%) were asymptomatic CRAG-positive. Positive results cases were cross-verified by performing LFA in whole blood. 3.1% of HIV-infected inpatients with CD4 <200 cells/μl without symptomatic meningitis had cryptococcal antigenemia in São Paulo, suggesting that routine CRAG screening may be beneficial in similar settings in South America. Our study reveals another targeted population for CRAG screening: hospitalised HIV-infected patients with CD4 <200 cells/μl, regardless of ART status. Whole blood CRAG LFA screening seems to be a simple strategy to prevention of symptomatic meningitis. © 2016 John Wiley & Sons Ltd.

Natural controlled HIV infection: Preserved HIV-specific immunity despite undetectable replication competent virus

International Nuclear Information System (INIS)

Kloosterboer, Nico; Groeneveld, Paul H.P.; Jansen, Christine A.; Vorst, Teun J.K. van der; Koning, Fransje; Winkel, Carel N.; Duits, Ashley J.; Miedema, Frank; Baarle, Debbie van; Rij, Ronald P. van; Brinkman, Kees; Schuitemaker, Hanneke

2005-01-01

Long-term non-progressive HIV infection, characterized by low but detectable viral load and stable CD4 counts in the absence of antiviral therapy, is observed in about 5% of HIV-infected patients. Here we identified four therapy naive individuals who are strongly seropositive for HIV-1 but who lack evidence of detectable HIV p24 antigen, plasma RNA, and proviral DNA in routine diagnostic testing. With an ultrasensitive PCR, we established that frequencies of pol proviral DNA sequences were as low as 0.2-0.5 copies/10 6 PBMC. HIV could not be isolated using up to 30 x 10 6 patient PBMC. One individual was heterozygous for CCR5 Δ32, but CCR5 expression on CD4 + T cells was normal to high in all four individuals. In vitro R5 and X4 HIV-1 susceptibility of CD8-depleted PBMC of all study subjects was significantly lower than the susceptibility of CD8-depleted PBMC of healthy blood donors. All individuals expressed protective HLA-B*58s alleles and showed evidence of HIV-specific cellular immunity either by staining with HLA-B*57 tetramers folded with an HIV RT or gag peptide or after stimulation with HIV-1 p24 gag, RT, or nef peptides in ELIspot analysis. HIV-specific CD4 + T helper cells were demonstrated by proliferation of CD4 + T cells and intracellular staining for IL-2 and IFNγ after stimulation with an HIV-gag peptide pool. Sera of all individuals showed antibody-mediated neutralization of both R5 and X4 HIV-1 variants. These data implicate that very low-level antigen exposure is sufficient for sustained HIV-specific immunity and suggest the possibility of a multi-factorial control of HIV infection

Mutational analysis of polyomavirus small-T-antigen functions in productive infection and in transformation.

Science.gov (United States)

Martens, I; Nilsson, S A; Linder, S; Magnusson, G

1989-05-01

The function of polyomavirus small T antigen in productive infection and in transformation was studied. Transfection of permissive mouse cells with mixtures of mutants that express only one type of T antigen showed that small T antigen increased large-T-antigen-dependent viral DNA synthesis approximately 10-fold. Under the same conditions, small T antigen was also essential for the formation of infectious virus particles. To analyze these activities of small T antigen, mutants producing protein with single amino acid replacements were constructed. Two mutants, bc1073 and bc1075, were characterized. Although both mutations led to the substitution of amino acid residues of more than one T antigen, the phenotype of both mutants was associated with alterations of the small T antigen. Both mutant proteins had lost their activity in the maturation of infectious virus particles. The bc1075 but not the bc1073 small T antigen had also lost its ability to stimulate viral DNA synthesis in mouse 3T6 cells. Finally, both mutants retained a third activity of small T antigen: to confer on rat cells also expressing middle T antigen the ability to grow efficiently in semisolid medium. The phenotypes of the mutants in these three assays suggest that small T antigen has at least three separate functions.

Short Communication: Comparison of Maxim and Sedia Limiting Antigen Assay Performance for Measuring HIV Incidence.

Science.gov (United States)

Schlusser, Katherine E; Konikoff, Jacob; Kirkpatrick, Allison R; Morrison, Charles; Chipato, Tsungai; Chen, Pai-Lien; Munjoma, Marshall; Eshleman, Susan H; Laeyendecker, Oliver

2017-06-01

Accurate methods for cross-sectional incidence estimation are needed for HIV prevention research. The Limiting Antigen Avidity (LAg-Avidity) assay has been marketed by two vendors, Maxim Biomedical and Sedia BioSciences Corporation. Performance differences between the two versions of the assay are unknown. We tested a total 1,410 treatment-naive samples with both versions of the assay. The samples came from 176 seroconverters from the Zimbabwe Hormonal Contraception and HIV Study. The correlation between the two versions of the assay was 0.93 for the optical density (OD) and 0.86 for the normalized OD. As the difference was more pronounced for the normalized OD, the difference in assays can be attributed to the calibrators. The mean duration of recent infection (MDRI), the average time individuals infected 1,000 copies/ml. The MDRI was 137 days for Sedia and 157 days for Maxim, with a difference of 20 days (95% CI 11-30). The MDRIs decreased to 102 and 120 days with the inclusion of a viral load cutoff of >1,000 copies/ml. These results imply that use of the Sedia LAg-Avidity will result in estimates of incidence ∼13% lower than those using the Maxim LAg-Avidity.

A new adenovirus based vaccine vector expressing an Eimeria tenella derived TLR agonist improves cellular immune responses to an antigenic target.

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Daniel M Appledorn

2010-03-01

Full Text Available Adenoviral based vectors remain promising vaccine platforms for use against numerous pathogens, including HIV. Recent vaccine trials utilizing Adenovirus based vaccines expressing HIV antigens confirmed induction of cellular immune responses, but these responses failed to prevent HIV infections in vaccinees. This illustrates the need to develop vaccine formulations capable of generating more potent T-cell responses to HIV antigens, such as HIV-Gag, since robust immune responses to this antigen correlate with improved outcomes in long-term non-progressor HIV infected individuals.In this study we designed a novel vaccine strategy utilizing an Ad-based vector expressing a potent TLR agonist derived from Eimeria tenella as an adjuvant to improve immune responses from a [E1-]Ad-based HIV-Gag vaccine. Our results confirm that expression of rEA elicits significantly increased TLR mediated innate immune responses as measured by the influx of plasma cytokines and chemokines, and activation of innate immune responding cells. Furthermore, our data show that the quantity and quality of HIV-Gag specific CD8(+ and CD8(- T-cell responses were significantly improved when coupled with rEA expression. These responses also correlated with a significantly increased number of HIV-Gag derived epitopes being recognized by host T cells. Finally, functional assays confirmed that rEA expression significantly improved antigen specific CTL responses, in vivo. Moreover, we show that these improved responses were dependent upon improved TLR pathway interactions.The data presented in this study illustrate the potential utility of Ad-based vectors expressing TLR agonists to improve clinical outcomes dependent upon induction of robust, antigen specific immune responses.

Are people living with HIV less productive at work?

NARCIS (Netherlands)

K. Verbooy (Kaya); M.N. Wagener (Marlies); M. Kaddouri (Meriam); P.D.D.M. Roelofs (Pepijn); H.S. Miedema (Harald); E.C.M. van Gorp (Eric); W.B.F. Brouwer (Werner); N.J.A. van Exel (Job)

2018-01-01

textabstractHealth problems may cause decreased productivity among working people. It is unclear if this also applies for people living with HIV (PLWH). This cross-sectional study compares data of PLWH of one of the main HIV treatment centres in the Netherlands (n = 298) to data of the general

The impact of pregnancy on the HIV-1-specific T cell function in infected pregnant women.

Science.gov (United States)

Hygino, Joana; Vieira, Morgana M; Kasahara, Taissa M; Xavier, Luciana F; Blanco, Bernardo; Guillermo, Landi V C; Filho, Renato G S; Saramago, Carmen S M; Lima-Silva, Agostinho A; Oliveira, Ariane L; Guimarães, Vander; Andrade, Arnaldo F B; Bento, Cleonice A M

2012-12-01

Evidences indicate that pregnancy can alter the Ag-specific T-cell responses. This work aims to evaluate the impact of pregnancy on the in vitro HIV-1-specific immune response. As compared with non-pregnant patients, lower T-cell proliferation and higher IL-10 production were observed in T-cell cultures from pregnant patients following addition of either mitogens or HIV-1 antigens. In our system, the main T lymphocyte subset involved in producing IL-10 was CD4(+)FoxP3(-). Depletion of CD4(+) cells elevated TNF-α and IFN-γ production. Interestingly, the in vitro HIV-1 replication was lower in cell cultures from pregnant patients, and it was inversely related to IL-10 production. In these cultures, the neutralization of IL-10 by anti-IL-10 mAb elevated TNF-α release and HIV-1 replication. In conclusion, our results reveal that pregnancy-related events should favor the expansion of HIV-1-specific IL-10-secreting CD4(+) T-cells in HIV-1-infected women, which should, in the scenario of pregnancy, help to reduce the risk of vertical HIV-1 transmission. Copyright © 2012 Elsevier Inc. All rights reserved.

Do HIV care providers appropriately manage hepatitis B in coinfected patients treated with antiretroviral therapy?

Science.gov (United States)

Jain, Mamta K; Opio, Christopher K; Osuagwu, Chukwuma C; Pillai, Rathi; Keiser, Philip; Lee, William M

2007-04-01

The common occurrence of hepatitis B virus (HBV) infection in patients who carry the human immunodeficiency virus (HIV) demands that both viruses be recognized, evaluated, and treated when appropriate. We identified 357 HIV- and hepatitis B surface antigen-positive patients who underwent testing from 1999 to 2003; 155 patients who were new to our clinic and who initiated therapy for HIV and HBV coinfection were considered for inclusion in the study. The frequency of HIV testing (to determine HIV load and CD4+ cell count) performed during the first year of therapy was compared with the frequency of HBV measurements (to determine hepatitis B e antigen, antibody to hepatitis B e antigen, and HBV load), abdominal ultrasound examination, and measurement of levels of alpha-fetoprotein in serum. HBV load data were obtained for only 16% of patients before initiation of antiretroviral therapy (ART), whereas HIV load was determined for 99% of patients before initiation of ART. The total number of HIV load measurements obtained during the first year after ART initiation was 497 (median number of HIV load measurements per patient, 3.0), compared with 85 measurements of HBV load (median number of HBV load measurements per patient, <1; P<.001). The percentage of patients who received any level of HBV monitoring (i.e., tests to determine hepatitis B e antigen, antibody to hepatitis B e antigen, and HBV load) after ART initiation increased from 7% in 1999 to 52% in 2001 (P<.001), whereas the percentage of patients who underwent HIV load testing remained at 80%-90% during the same period. Health care providers treating patients with HIV infection during the period 1999-2003 infrequently monitored HBV response in coinfected patients, but they systematically monitored HIV response after ART initiation. Improved physician adherence to guidelines that better delineate HBV treatment and monitoring for patients with HIV-HBV coinfection is needed.

Correlation between carbohydrate structures on the envelope glycoprotein gp120 of HIV-1 and HIV-2 and syncytium inhibition with lectins

DEFF Research Database (Denmark)

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

1989-01-01

The binding of 13 different lectins to gp120 partially purified from two HIV-1 isolates and one HIV-2 isolate was studied by in situ staining on electrophoretically separated and electroblotted HIV antigens. The lectins concanavalin A, wheat germ agglutinin, Lens culinaris agglutinin, Vicia faba...

CD4- and dynamin-dependent endocytosis of HIV-1 into plasmacytoid dendritic cells

Energy Technology Data Exchange (ETDEWEB)

Pritschet, Kathrin; Donhauser, Norbert; Schuster, Philipp; Ries, Moritz; Haupt, Sabrina; Kittan, Nicolai A.; Korn, Klaus [Institute of Clinical and Molecular Virology, National Reference Centre for Retroviruses, Friedrich-Alexander-Universitaet Erlangen-Nuernberg, 91054 Erlangen (Germany); Poehlmann, Stefan [Institute of Virology, Hannover Medical School, 30625 Hannover (Germany); Holland, Gudrun; Bannert, Norbert [Robert Koch-Institute, Center for Biological Security 4, 13353 Berlin (Germany); Bogner, Elke [Institute of Virology, Charite University Hospital, 10117 Berlin (Germany); Schmidt, Barbara, E-mail: baschmid@viro.med.uni-erlangen.de [Institute of Clinical and Molecular Virology, National Reference Centre for Retroviruses, Friedrich-Alexander-Universitaet Erlangen-Nuernberg, 91054 Erlangen (Germany)

2012-02-20

Chronic immune activation, triggered by plasmacytoid dendritic cell (PDC) interferon (IFN)-alpha production, plays an important role in HIV-1 pathogenesis. As the entry of HIV-1 seems to be important for the activation of PDC, we directly characterized the viral entry into these cells using immuno-electron microscopy, cellular fractionation, confocal imaging, and functional experiments. After attachment to PDC, viruses were taken up in an energy-dependent manner. The virions were located in compartments positive for caveolin; early endosomal antigen 1; Rab GTPases 5, 7 and 9; lysosomal-associated membrane protein 1. PDC harbored more virus in endocytic vesicles than CD4+ T cells (p < 0.05). Blocking CD4 inhibited the uptake of virions into cytosolic and endosomal compartments. Dynasore, an inhibitor of dynamin-dependent endocytosis, not the fusion inhibitor T-20, reduced the HIV-1 induced IFN-alpha production. Altogether, our morphological and functional data support the role of endocytosis for the entry and IFN-alpha induction of HIV-1 in PDC.

Long-term persistence and function of hematopoietic stem cell-derived chimeric antigen receptor T cells in a nonhuman primate model of HIV/AIDS.

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Anjie Zhen

2017-12-01

Full Text Available Chimeric Antigen Receptor (CAR T-cells have emerged as a powerful immunotherapy for various forms of cancer and show promise in treating HIV-1 infection. However, significant limitations are persistence and whether peripheral T cell-based products can respond to malignant or infected cells that may reappear months or years after treatment remains unclear. Hematopoietic Stem/Progenitor Cells (HSPCs are capable of long-term engraftment and have the potential to overcome these limitations. Here, we report the use of a protective CD4 chimeric antigen receptor (C46CD4CAR to redirect HSPC-derived T-cells against simian/human immunodeficiency virus (SHIV infection in pigtail macaques. CAR-containing cells persisted for more than 2 years without any measurable toxicity and were capable of multilineage engraftment. Combination antiretroviral therapy (cART treatment followed by cART withdrawal resulted in lower viral rebound in CAR animals relative to controls, and demonstrated an immune memory-like response. We found CAR-expressing cells in multiple lymphoid tissues, decreased tissue-associated SHIV RNA levels, and substantially higher CD4/CD8 ratios in the gut as compared to controls. These results show that HSPC-derived CAR T-cells are capable of long-term engraftment and immune surveillance. This study demonstrates for the first time the safety and feasibility of HSPC-based CAR therapy in a large animal preclinical model.

HIV-1 envelope glycoprotein

Science.gov (United States)

Caulfield, Michael; Cupo, Albert; Dean, Hansi; Hoffenberg, Simon; King, C. Richter; Klasse, P. J.; Marozsan, Andre; Moore, John P.; Sanders, Rogier W.; Ward, Andrew; Wilson, Ian; Julien, Jean-Philippe

2017-08-22

The present application relates to novel HIV-1 envelope glycoproteins, which may be utilized as HIV-1 vaccine immunogens, and antigens for crystallization, electron microscopy and other biophysical, biochemical and immunological studies for the identification of broad neutralizing antibodies. The present invention encompasses the preparation and purification of immunogenic compositions, which are formulated into the vaccines of the present invention.

HIV and mature dendritic cells: Trojan exosomes riding the Trojan horse?

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Nuria Izquierdo-Useros

2010-03-01

Full Text Available Exosomes are secreted cellular vesicles that can induce specific CD4(+ T cell responses in vivo when they interact with competent antigen-presenting cells like mature dendritic cells (mDCs. The Trojan exosome hypothesis proposes that retroviruses can take advantage of the cell-encoded intercellular vesicle traffic and exosome exchange pathway, moving between cells in the absence of fusion events in search of adequate target cells. Here, we discuss recent data supporting this hypothesis, which further explains how DCs can capture and internalize retroviruses like HIV-1 in the absence of fusion events, leading to the productive infection of interacting CD4(+ T cells and contributing to viral spread through a mechanism known as trans-infection. We suggest that HIV-1 can exploit an exosome antigen-dissemination pathway intrinsic to mDCs, allowing viral internalization and final trans-infection of CD4(+ T cells. In contrast to previous reports that focus on the ability of immature DCs to capture HIV in the mucosa, this review emphasizes the outstanding role that mature DCs could have promoting trans-infection in the lymph node, underscoring a new potential viral dissemination pathway.

Vorinostat Renders the Replication-Competent Latent Reservoir of Human Immunodeficiency Virus (HIV Vulnerable to Clearance by CD8 T Cells

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Julia A. Sung

2017-09-01

Full Text Available Latently human immunodeficiency virus (HIV-infected cells are transcriptionally quiescent and invisible to clearance by the immune system. To demonstrate that the latency reversing agent vorinostat (VOR induces a window of vulnerability in the latent HIV reservoir, defined as the triggering of viral antigen production sufficient in quantity and duration to allow for recognition and clearance of persisting infection, we developed a latency clearance assay (LCA. The LCA is a quantitative viral outgrowth assay (QVOA that includes the addition of immune effectors capable of clearing cells expressing viral antigen. Here we show a reduction in the recovery of replication-competent virus from VOR exposed resting CD4 T cells following addition of immune effectors for a discrete period. Take home message: VOR exposure leads to sufficient production of viral protein on the cell surface, creating a window of vulnerability within this latent reservoir in antiretroviral therapy (ART-suppressed HIV-infected individuals that allows the clearance of latently infected cells by an array of effector mechanisms.

Impaired production of cytokines is an independent predictor of mortality in HIV-1-infected patients

DEFF Research Database (Denmark)

Ostrowski, Sisse R; Gerstoft, Jan; Pedersen, Bente K

2003-01-01

With regard to the natural history of HIV-1 infection this study investigated whether whole-blood culture cytokine production was associated with mortality in HIV-1-infected patients.......With regard to the natural history of HIV-1 infection this study investigated whether whole-blood culture cytokine production was associated with mortality in HIV-1-infected patients....

Immunization of neonatal mice with LAMP/p55 HIV gag DNA elicits robust immune responses that last to adulthood

International Nuclear Information System (INIS)

Ordonhez Rigato, Paula; Maciel, Milton; Goldoni, Adriana Leticia; Piubelli, Orlando; Alves de Brito, Cyro; Fusaro, Ana Elisa; Eurico de Alencar, Liciana Xavier; August, Thomas; Torres Azevedo Marques, Ernesto; Silva Duarte, Alberto Jose da; Sato, Maria Notomi

2010-01-01

Successful T cell priming in early postnatal life that can generate effective long-lasting responses until adulthood is critical in HIV vaccination strategies because it prevents early sexual initiation and breastfeeding transmission of HIV. A chimeric DNA vaccine encoding p55 HIV gag associated with lysosome-associated membrane protein 1 (LAMP-1; which drives the antigen to the MIIC compartment), has been used to enhance cellular and humoral antigen-specific responses in adult mice and macaques. Herein, we investigated LAMP-1/gag vaccine immunogenicity in the neonatal period in mice and its ability to generate long-lasting effects. Neonatal vaccination with chimeric LAMP/gag generated stronger Gag-specific immune responses, as measured by the breadth of the Gag peptide-specific IFN-γ, proliferative responsiveness, cytokine production and antibody production, all of which revealed activation of CD4+ T cells as well as the generation of a more robust CTL response compared to gag vaccine alone. To induce long-lived T and B cell memory responses, it was necessary to immunize neonates with the chimeric LAMP/gag DNA vaccine. The LAMP/gag DNA vaccine strategy could be particularly useful for generating an anti-HIV immune response in the early postnatal period capable of inducing long-term immunological memory.

Elimination of high titre HIV from fibreoptic endoscopes.

Science.gov (United States)

Hanson, P J; Gor, D; Jeffries, D J; Collins, J V

1990-06-01

Concern about contamination of fibreoptic endoscopes with human immunodeficiency virus (HIV) has generated a variety of disruptive and possibly unnecessary infection control practices in endoscopy units. Current recommendations on the cleaning and disinfection of endoscopes have been formulated without applied experimental evidence of the effective removal of HIV from endoscopes. To study the kinetics of elimination of HIV from endoscope surfaces, we artificially contaminated the suction-biopsy channels of five Olympus GIF XQ20 endoscopes with high titre HIV in serum. The air and water channels of two instruments were similarly contaminated. Contamination was measured by irrigating channels with viral culture medium and collecting 3 ml at the distal end for antigen immunoassay. Endoscopes were then cleaned manually in neutral detergent according to the manufacturer's recommendations and disinfected in 2% alkaline glutaraldehyde (Cidex, Surgikos) for two, four, and ten minutes. Contamination with HIV antigens was measured before and after cleaning and after each period of disinfection. Initial contamination comprised 4.8 x 10(4) to 3.5 x 10(6) pg HIV antigen/ml. Cleaning in detergent achieved a reduction to 165 pg/ml (99.93%) on one endoscope and to undetectable levels (100%) on four. After two minutes in alkaline glutaraldehyde all samples were negative and remained negative after the longer disinfection times. Air and water channels, where contaminated, were tested after 10 minutes' disinfection and were negative. These findings underline the importance of cleaning in removing HIV from endoscope and indicate that the use of dedicated equipment and long disinfection times are unnecessary.

HLA class I antigen processing machinery (APM) component expression and PD-1:PD-L1 pathway activation in HIV-infected head and neck cancers.

Science.gov (United States)

Pai, Sara I; Jack Lee, J; Carey, Thomas E; Westra, William H; Ferrone, Soldano; Moore, Charles; Mosunjac, Marina B; Shin, Dong M; Ferris, Robert L

2018-02-01

Human immunodeficiency virus (HIV)-infected individuals are at increased risk for developing several non-AIDS related malignancies and are often excluded from cancer immunotherapy regimens. To evaluate the immune competence of this cancer patient population, we evaluated HLA class I antigen presenting machinery (APM) component expression and PD-1:PD-L1 pathway upregulation in HIV(+) and HIV(-) head and neck cancers (HNCs). Sixty-two HIV(+) and 44 matched HIV(-) controls diagnosed with HNC between 1991 and 2011 from five tertiary care referral centers in the United States were identified. HLA class I APM component, PD-1, and PD-L1 expression were analyzed by immunohistochemical staining with monoclonal antibodies (mAbs). Clinical data was abstracted from the medical records. There was no significant difference between the cases and controls in LMP2, TAP1, HLA-A and HLA-B/C, as well as PD-1 and PD-L1 expression. Overall, 62% of all subjects had high PD-1 expression and 82% of the subjects expressed PD-L1 within the tumor microenvironment. LMP2, HLA-A and HLA-B/C expression were significantly associated with moderate to high PD-1 expression in the HIV(+) HNC cases (p = .004, p = .026, and p = .006, respectively) but not in the HIV(-) controls. In addition, HLA-A expression was significantly associated with PD-L1 expression in the HIV(+) HNC cases only (p = .029). HIV-infected individuals diagnosed with HNC do not have any detectable defects in HLA class I APM component expression and in PD-1:PD-L1 pathway activation. Given the current successes of HAART therapy in maintaining immune cell counts, HIV(+) patients diagnosed with cancer may benefit from the recently FDA-approved immune checkpoint blockade therapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

Current Peptide and Protein Candidates Challenging HIV Therapy beyond the Vaccine Era

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Koollawat Chupradit

2017-09-01

Full Text Available Human immunodeficiency virus (HIV is a causative agent of acquired immune deficiency syndrome (AIDS. Highly active antiretroviral therapy (HAART can slow down the replication of HIV-1, leading to an improvement in the survival of HIV-1-infected patients. However, drug toxicities and poor drug administration has led to the emergence of a drug-resistant strain. HIV-1 immunotherapy has been continuously developed, but antibody therapy and HIV vaccines take time to improve its efficiency and have limitations. HIV-1-specific chimeric antigen receptor (CAR-based immunotherapy founded on neutralizing antibodies is now being developed. In HIV-1 therapy, anti-HIV chimeric antigen receptors showed promising data in the suppression of HIV-1 replication; however, autologous transfusion is still a problem. This has led to the development of effective peptides and proteins for an alternative HIV-1 treatment. In this paper, we provide a comprehensive review of potent anti-HIV-1 peptides and proteins that reveal promising therapeutic activities. The inhibitory mechanisms of each therapeutic molecule in the different stages of the HIV-1 life cycle will be discussed herein.

Association of genital mycoplasmas including Mycoplasma genitalium in HIV infected men with nongonococcal urethritis attending STD & HIV clinics.

Science.gov (United States)

Manhas, Ashwini; Sethi, Sunil; Sharma, Meera; Wanchu, Ajay; Kanwar, A J; Kaur, Karamjit; Mehta, S D

2009-03-01

Acute nongonococcal urethritis (NGU) is one of the commonest sexually transmitted infections affecting men. The role of genital mycoplasmas including Mycoplasma genitalium in HIV infected men with NGU is still not known. The aim of this study was to determine the isolation pattern/detection of genital mycoplasma including M. genitalium in HIV infected men with NGU and to compare it with non HIV infected individuals. One hundred male patients with NGU (70 HIV positive, 30 HIV negative) were included in the study. Urethral swabs and urine samples obtained from patients were subjected to semi-quantitative culture for Mycoplasma hominis and Ureaplasama urealyticum, whereas M. genitalium was detected by PCR from urine. The primers MgPa1 and MgPa3 were selected to identify 289 bp product specific for M. genitalium. Chalmydia trachomatis antigen detection was carried out by ELISA. M. genitalium and M. hominis were detected/isolated in 6 per cent of the cases. M. genitalium was more common amongst HIV positive cases (7.1%) as compared to HIV negative cases (3.3%) but difference was not statistically significant. Co-infection of C. trachomatis and U. urealyticum was found in two HIV positive cases whereas, C. trachomatis and M. hominis were found to be coinfecting only one HIV positive individual. M. genitalium was found to be infecting the patients as the sole pathogen. Patients with NGU had almost equal risk of being infected with M. genitalium, U. urealyticum or M. hominis irrespective of their HIV status. M.genitalium constitutes one of the important causes of NGU besides other genital mycoplasmas.

THE THEORETICAL AND PRACTICAL ASPECTS OF THE RECOMBINANT ANTIGENS FOR THE DIAGNOSIS OF BOVINE LEUKEMIA PRODUCTION

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Shapovalova OV

2016-12-01

Full Text Available Introduction. Nowadays the problem of bovine leukemia (EBL effective diagnosis in countries where EBL is registered and the disease-free areas remains actual. The main diagnostic tests are immunodiffusion reaction (AGID and enzyme-linked immunosorbent assay (ELISA, which allow the identification of infected animals by the presence of antibodies to bovine leukemia virus (BLV both in serum and in milk samples. The effectiveness of these methods depends on the quality of diagnostic test systems used and determines by the cultural and recombinant virus antigens specificity. EBL recombinant antigens have certain advantages as they are more active and cheap. Purpose of the work. The analysis of theoretical and practical approaches in the bovine leukemia virus recombinant antigens development and its diagnostic potential evaluation. The article contains data from the literature on the recombinant antigens of bovine leukemia virus construction and use. Analysis of the literature showed that the recombinant proteins are widely used in the serological diagnosis of bovine leukemia. Numerous protocols of BLV gp51 and p24 immunodominant antigens preparation has been developed in heterologous systems (Saccharomyces cerevisiae, E. coli, vaccinia virus, baculovirus. In order to obtain recombinant antigens, the BLV provirus genome regions isolated from FLK-BLV cell culture, lymphocytes or tumor cells from naturally infected cattle are typically used. For the recombinant antigens labeled by hexahistidine or Srept II purification one-step immobilized-metal affinity chromatography IMAC and highly selective Strep-Tactin affinity chromatography methods are carried out. The end products activity and specificity are studied in the immunoblotting, ELISA and AGID diagnostic reactions. The ukrainian scientists’ publications are devoted to the clone E. coli HB101-2 transformed by the recombinant plasmid containing fully functional BLV env and gag genes nucleotide

Gastrointestinal immune responses in HIV infected subjects

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LRR Castello-Branco

1996-06-01

Full Text Available The gut associated lymphoid tissue is responsible for specific responses to intestinal antigens. During HIV infection, mucosal immune deficiency may account for the gastrointestinal infections. In this review we describe the humoral and cellular mucosal immune responses in normal and HIV-infected subjects.

Isolation of antigenic substances from HIV-1 envelope gp160 gene transfectants by mild acid elution and X-irradiation treatment. For the development of CTL-based immunotherapy

International Nuclear Information System (INIS)

Fujimoto, Chiaki; Nakagawa, Yohko; Shimizu, Masumi; Ohara, Kunitoshi; Takahashi, Hidemi

2003-01-01

Cytotoxic T lymphocytes (CTLs) play a central role in a broad spectrum of tumor immunity. Such CTLs generally recognize processed antigenic fragments in association with class I major histocompatibility complex (MHC) molecules. Thus, it is important to identify naturally processed antigens associated with class I MHC molecules to generate and activate antigen-specific CTLs. Those processed antigens fitted in the groove of class I MHC molecules are fixed by the β2-microglobulin. Mild acid elution is one method used to isolate antigenic fragments from class I MHC molecules on tumor cells by unfastening a clasp of β2-microglobulin, a critical component for stabilizing class I MHC molecules on the cell surface. Indeed, after the mild acid treatment, the expression of class I MHC molecules was temporarily down-modulated and a strong antigenic fraction for CTL recognition was obtained. To our surprise, such down-modulation of class I MHC molecule expression was also observed when the tumor cells were irradiated. Therefore, using human immunodeficiency virus type I (HIV-1) gp160 env gene transfectants, we examined the effect of X-irradiation on releasing the loaded antigenic fragments. Functional extracts were obtained from X-irradiated cell supernatants that sensitized syngeneic fibroblasts for specific CTL recognition, suggesting that X-irradiation extracts would also contain known antigenic epitopes. These results indicate that, in addition to the conventional mild acid elution treatment, X-irradiation method shown in this paper may provide a new approach for CTL-based vaccine development via isolating antigenic molecules from various tumors or virally infected cells. (author)

Clinical Improvement by Switching to an Integrase Strand Transfer Inhibitor in Hemophiliac Patients with HIV: The Japan Cohort Study of HIV Patients Infected through Blood Products.

Science.gov (United States)

Kawado, Miyuki; Hashimoto, Shuji; Oka, Shin-Ichi; Fukutake, Katsuyuki; Higasa, Satoshi; Yatsuhashi, Hiroshi; Ogane, Miwa; Okamoto, Manabu; Shirasaka, Takuma

2017-01-01

This study aimed to determine improvement in HIV RNA levels and the CD4 cell count by switching to an antiretroviral regimen with an integrase strand transfer inhibitor (INSTI) in patients with HIV. This study was conducted on Japanese patients with HIV who were infected by blood products in the 1980s. Data were collected between 2007 and 2014. Data of 564 male hemophiliac patients with HIV from the Japan Cohort Study of HIV Patients Infected through Blood Products were available. Changes in antiretroviral regimen use, HIV RNA levels, and the CD4 cell count between 2007 and 2014 were examined. From 2007 to 2014, the proportion of use of a regimen with an INSTI increased from 0.0% to 41.0%. For patients with HIV who used a regimen, including an INSTI, the proportion of HIV RNA levels products. This suggests that performing this switch in clinical practice will lead to favorable effects.

Loss of long term protection with the inclusion of HIV pol to a DNA vaccine encoding gag.

Science.gov (United States)

Garrod, Tamsin J; Gargett, Tessa; Yu, Wenbo; Major, Lee; Burrell, Christopher J; Wesselingh, Steven; Suhrbier, Andreas; Grubor-Bauk, Branka; Gowans, Eric J

2014-11-04

Traditional vaccine strategies that induce antibody responses have failed to protect against HIV infection in clinical trials, and thus cell-mediated immunity is now an additional criterion. Recent clinical trials that aimed to induce strong T cell responses failed to do so. Therefore, to enhance induction of protective T cell responses, it is crucial that the optimum antigen combination is chosen. Limited research has been performed into the number of antigens selected for an HIV vaccine. This study aimed to compare DNA vaccines encoding either a single HIV antigen or a combination of two antigens, using intradermal vaccination of C57BL/6 mice. Immune assays were performed on splenocytes, and in vivo protection was examined by challenge with a chimeric virus, EcoHIV, able to infect mouse but not human leukocytes, at 10 days (short term) and 60 days (long term) post final vaccination. At 60 days there was significantly lower frequency of induced antigen-specific CD8(+) T cells in the spleens of pCMVgag-pol-vaccinated mice compared with mice which received pCMVgag only. Most importantly, short term viral control of EcoHIV was similar for pCMVgag and pCMVgag-pol-vaccinated mice at day 10, but only the pCMVgag-vaccinated significantly controlled EcoHIV at day 60 compared with pCMV-vaccinated mice, showing that control was reduced with the inclusion of the HIV pol gene. Copyright © 2014 Elsevier B.V. All rights reserved.

Composition and Antigenic Effects of Individual Glycan Sites of a Trimeric HIV-1 Envelope Glycoprotein

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Anna-Janina Behrens

2016-03-01

Full Text Available The HIV-1 envelope glycoprotein trimer is covered by an array of N-linked glycans that shield it from immune surveillance. The high density of glycans on the trimer surface imposes steric constraints limiting the actions of glycan-processing enzymes, so that multiple under-processed structures remain on specific areas. These oligomannose glycans are recognized by broadly neutralizing antibodies (bNAbs that are not thwarted by the glycan shield but, paradoxically, target it. Our site-specific glycosylation analysis of a soluble, recombinant trimer (BG505 SOSIP.664 maps the extremes of simplicity and diversity of glycan processing at individual sites and reveals a mosaic of dense clusters of oligomannose glycans on the outer domain. Although individual sites usually minimally affect the global integrity of the glycan shield, we identify examples of how deleting some glycans can subtly influence neutralization by bNAbs that bind at distant sites. The network of bNAb-targeted glycans should be preserved on vaccine antigens.

Human Immunodeficiency Virus (HIV types Western blot (WB band profiles as potential surrogate markers of HIV disease progression and predictors of vertical transmission in a cohort of infected but antiretroviral therapy naïve pregnant women in Harare, Zimbabwe

Directory of Open Access Journals (Sweden)

Chirenje Mike Z

2011-01-01

Full Text Available Abstract Background Expensive CD4 count and viral load tests have failed the intended objective of enabling access to HIV therapy in poor resource settings. It is imperative to develop simple, affordable and non-subjective disease monitoring tools to complement clinical staging efforts of inexperienced health personnel currently manning most healthcare centres because of brain drain. Besides accurately predicting HIV infection, sequential appearance of specific bands of WB test offers a window of opportunity to develop a less subjective tool for monitoring disease progression. Methods HIV type characterization was done in a cohort of infected pregnant women at 36 gestational weeks using WB test. Student-t test was used to determine maternal differences in mean full blood counts and viral load of mothers with and those without HIV gag antigen bands. Pearson Chi-square test was used to assess differences in lack of bands appearance with vertical transmission and lymphadenopathy. Results Among the 64 HIV infected pregnant women, 98.4% had pure HIV-1 infection and one woman (1.7% had dual HIV-1/HIV-2 infections. Absence of HIV pol antigen bands was associated with acute infection, p = 0.002. All women with chronic HIV-1 infection had antibody reactivity to both the HIV-1 envelope and polymerase antigens. However, antibody reactivity to gag antigens varied among the women, being 100%, 90%, 70% and 63% for p24, p17, p39 and p55, respectively. Lack of antibody reactivity to gag p39 antigen was associated with disease progression as confirmed by the presence of lymphadenopathy, anemia, higher viral load, p = 0.010, 0.025 and 0.016, respectively. Although not statistically significant, women with p39 band missing were 1.4 times more likely to transmit HIV-1 to their infants. Conclusion Absence of antibody reactivity to pol and gag p39 antigens was associated with acute infection and disease progression, respectively. Apart from its use in HIV disease

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

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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.

Interleukin production by neonatal spleen cells during and as a result of antigen presentation: The effect of ultraviolet light

International Nuclear Information System (INIS)

Levin, D.; Gershon, H.

1989-01-01

Antigen presentation by neonatal murine spleen cells and the production of lymphokines and interleukins involved in the stimulation of a T-helper-2 (TH2) cell line (D10-G4.1) were studied as were the effects of ultra violet (UV)-irradiation on this system. Neonatal spleen cells are less capable than adult cells of performing the initial steps of the immune response required for antigen dependent activation of TH2 cells. These steps include soluble antigen processing and presentation and as a result reduced production of IL-4 and IL-1-Inducer Factor (IL-1-IF) by the T-helper cells and reduced production of IL-1 and IL-2 by the antigen presenting cell population. Spontaneous membrane IL-1 activity is low in the neonate, however, when exposed to IL-1-IF they can express adult levels. Ultraviolet (UV) irradiation of the antigen presenting population has a damaging effect on all the above mentioned processes. Antigen processing and presentation, induction of D10 IL-4 production and proliferation, and IL-2 production demonstrate two different age related patterns of UV-irradiation induced damage: a dose dependent inhibition when adult cells are irradiated and an inverse effect in which low doses of irradiation were more inhibitory than higher doses when neonatal cells are irradiated. However, the secretion and membrane expression of IL-1 by both age groups are directly and totally inhibited by the range of UV-irradiation doses used and cannot be reinduced with a supplement of a crude IL-1-IF. While the capacity to produced IL-1 is totally destroyed by UV-irradiation, the ability to produce IL-2 remains intact and remains responsive to an IL-2-Inducer activity during proper antigen presentation. The low responses of neonatal antigen presenting spleen cell populations and the damaging effect of UV on both neonatal and adult responses are not due to the induction of suppressor factors

Analysis of the Effect of HIV/AIDS on Productivity and Welfare of ...

African Journals Online (AJOL)

Analysis of the Effect of HIV/AIDS on Productivity and Welfare of Women Farmers in ... a tremendous increase in prevalence rate of HIV/AIDS epidemic in recent time, ... reduction in cash flow while 22% complained about their inability to work.

Expanded breadth of the T-cell response to mosaic HIV-1 envelope DNA vaccination

Energy Technology Data Exchange (ETDEWEB)

Korber, Bette [Los Alamos National Laboratory; Fischer, William [Los Alamos National Laboratory; Wallstrom, Timothy [Los Alamos National Laboratory

2009-01-01

An effective AIDS vaccine must control highly diverse circulating strains of HIV-1. Among HIV -I gene products, the envelope (Env) protein contains variable as well as conserved regions. In this report, an informatic approach to the design of T-cell vaccines directed to HIV -I Env M group global sequences was tested. Synthetic Env antigens were designed to express mosaics that maximize the inclusion of common potential Tcell epitope (PTE) 9-mers and minimize the inclusion of rare epitopes likely to elicit strain-specific responses. DNA vaccines were evaluated using intracellular cytokine staining (ICS) in inbred mice with a standardized panel of highly conserved 15-mer PTE peptides. I, 2 and 3 mosaic sets were developed that increased theoretical epitope coverage. The breadth and magnitude ofT-cell immunity stimulated by these vaccines were compared to natural strain Env's; additional comparisons were performed on mutant Env's, including gpl60 or gpl45 with or without V regions and gp41 deletions. Among them, the 2 or 3 mosaic Env sets elicited the optimal CD4 and CD8 responses. These responses were most evident in CD8 T cells; the 3 mosaic set elicited responses to an average of 8 peptide pools compared to 2 pools for a set of3 natural Env's. Synthetic mosaic HIV -I antigens can therefore induce T-cell responses with expanded breadth and may facilitate the development of effective T -cell-based HIV -1 vaccines.

Recombinant hepatitis B surface antigen production in Aspergillus niger: evaluating the strategy of gene fusion to native glucoamylase

CSIR Research Space (South Africa)

James, ER

2012-10-01

Full Text Available Microbiology and Biotechnology October 2012/ Vol. 96, No.2 Recombinant hepatitis B surface antigen production in Aspergillus niger: evaluating the strategy of gene fusion to native glucoamylase ER James a,c & WH van Zyl b & PJ van Zyl c & JF Görgens..., Pretoria 0001, South Africa Abstract This study demonstrates the potential of Aspergillus niger as a candidate expression system for virus- like particle production using gene fusion. Hepatitis B surface antigen (HBsAg) production, targeted...

Evolution of hepatitis B serological markers in HIV coinfected patients: a case study

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Ana Luiza de Castro Conde Toscano

Full Text Available ABSTRACT OBJECTIVE To describe the evolution of serological markers among HIV and hepatitis B coinfected patients, with emphasis on evaluating the reactivation or seroreversion of these markers. METHODS The study population consisted of patients met in an AIDS Outpatient Clinic in São Paulo State, Brazil. We included in the analysis all HIV-infected and who underwent at least two positive hepatitis B surface antigen serological testing during clinical follow up, with tests taken six months apart. Patients were tested with commercial kits available for hepatitis B serological markers by microparticle enzyme immunoassay. Clinical variables were collected: age, sex, CD4+ T-cell count, HIV viral load, alanine aminotransferase level, exposure to antiretroviral drugs including lamivudine and/or tenofovir. RESULTS Among 2,242 HIV positive patients, we identified 105 (4.7% patients with chronic hepatitis B. Follow up time for these patients varied from six months to 20.5 years. All patients underwent antiretroviral therapy during follow-up. Among patients with chronic hepatitis B, 58% were hepatitis B “e” antigen positive at the first assessment. Clearance of hepatitis B surface antigen occurred in 15% (16/105 of patients with chronic hepatitis B, and 50% (8/16 of these patients presented subsequent reactivation or seroreversion of hepatitis B surface antigen. Among hepatitis B “e” antigen positive patients, 57% (35/61 presented clearance of this serologic marker. During clinical follow up, 28.5% (10/35 of those who initially cleared hepatitis B “e” antigen presented seroreversion or reactivation of this marker. CONCLUSIONS Among HIV coinfected patients under antiretroviral therapy, changes of HBV serological markers were frequently observed. These results suggest that frequent monitoring of these serum markers should be recommended.

Perforin expression directly ex vivo by HIV-specific CD8 T-cells is a correlate of HIV elite control.

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Adam R Hersperger

2010-05-01

Full Text Available Many immune correlates of CD8(+ T-cell-mediated control of HIV replication, including polyfunctionality, proliferative ability, and inhibitory receptor expression, have been discovered. However, no functional correlates using ex vivo cells have been identified with the known ability to cause the direct elimination of HIV-infected cells. We have recently discovered the ability of human CD8(+ T-cells to rapidly upregulate perforin--an essential molecule for cell-mediated cytotoxicity--following antigen-specific stimulation. Here, we examined perforin expression capability in a large cross-sectional cohort of chronically HIV-infected individuals with varying levels of viral load: elite controllers (n = 35, viremic controllers (n = 29, chronic progressors (n = 27, and viremic nonprogressors (n = 6. Using polychromatic flow cytometry and standard intracellular cytokine staining assays, we measured perforin upregulation, cytokine production, and degranulation following stimulation with overlapping peptide pools encompassing all proteins of HIV. We observed that HIV-specific CD8(+ T-cells from elite controllers consistently display an enhanced ability to express perforin directly ex vivo compared to all other groups. This ability is not restricted to protective HLA-B haplotypes, does not require proliferation or the addition of exogenous factors, is not restored by HAART, and primarily originates from effector CD8(+ T-cells with otherwise limited functional capability. Notably, we found an inverse relationship between HIV-specific perforin expression and viral load. Thus, the capability of HIV-specific CD8(+ T-cells to rapidly express perforin defines a novel correlate of control in HIV infection.

Antigenic properties of a transport-competent influenza HA/HIV Env chimeric protein

International Nuclear Information System (INIS)

Ye Ling; Sun Yuliang; Lin Jianguo; Bu Zhigao; Wu Qingyang; Jiang, Shibo; Steinhauer, David A.; Compans, Richard W.; Yang Chinglai

2006-01-01

The transmembrane subunit (gp41) of the HIV Env glycoprotein contains conserved neutralizing epitopes which are not well-exposed in wild-type HIV Env proteins. To enhance the exposure of these epitopes, a chimeric protein, HA/gp41, in which the gp41 of HIV-1 89.6 envelope protein was fused to the C-terminus of the HA1 subunit of the influenza HA protein, was constructed. Characterization of protein expression showed that the HA/gp41 chimeric proteins were expressed on cell surfaces and formed trimeric oligomers, as found in the HIV Env as well as influenza HA proteins. In addition, the HA/gp41 chimeric protein expressed on the cell surface can also be cleaved into 2 subunits by trypsin treatment, similar to the influenza HA. Moreover, the HA/gp41 chimeric protein was found to maintain a pre-fusion conformation. Interestingly, the HA/gp41 chimeric proteins on cell surfaces exhibited increased reactivity to monoclonal antibodies against the HIV Env gp41 subunit compared with the HIV-1 envelope protein, including the two broadly neutralizing monoclonal antibodies 2F5 and 4E10. Immunization of mice with a DNA vaccine expressing the HA/gp41 chimeric protein induced antibodies against the HIV gp41 protein and these antibodies exhibit neutralizing activity against infection by an HIV SF162 pseudovirus. These results demonstrate that the construction of such chimeric proteins can provide enhanced exposure of conserved epitopes in the HIV Env gp41 and may represent a novel vaccine design strategy for inducing broadly neutralizing antibodies against HIV

Comparison of three techniques for production goat lentivirus antigen used in the agar gel immunodifusion test

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Raymundo Rizaldo Pinheiro

2005-12-01

Full Text Available The Caprine Arthritis Encephalitis (CAE is a disease who cause considerable economic losses, including loss in the milk production and reduction of the useful life of the animal. In the diagnosis of this disease the agar gel immunodifusion test (AGID is used worldwide as the selection test. The objective of thid work was to test three different concentrations of bovine fetal serum (BFS in the production of the antigen (Ag for the diagnosis of the CAE virus (CAEV, to verify amongst the three methods the most efficient concentration and which the antigen concentration of the antigen produced is appropriate for the test. The method of the AMICON and the concentration of the Ag for dialysis was indicated, however the system AMICON, despite the implantation costs, promoted minor loss of antigen, little time expense in the processing and greater simplicity. With relation to the amount of BFS placed after the viral inoculation it was verified that 5% of BFS the amount that presented better resulted. The antigen concentration 100 times was more indicated, therefore it allowed the diagnosis of the CAEV for two proteins (gp 135 and p28. The concentration of the Ag for precipitation/ultracentrifugation, used for imunoenzimatic tests, did not present resulted satisfactory used in the AGID.

Tetherin restricts productive HIV-1 cell-to-cell transmission.

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Nicoletta Casartelli

2010-06-01

Full Text Available The IFN-inducible antiviral protein tetherin (or BST-2/CD317/HM1.24 impairs release of mature HIV-1 particles from infected cells. HIV-1 Vpu antagonizes the effect of tetherin. The fate of virions trapped at the cell surface remains poorly understood. Here, we asked whether tetherin impairs HIV cell-to-cell transmission, a major means of viral spread. Tetherin-positive or -negative cells, infected with wild-type or DeltaVpu HIV, were used as donor cells and cocultivated with target lymphocytes. We show that tetherin inhibits productive cell-to-cell transmission of DeltaVpu to targets and impairs that of WT HIV. Tetherin accumulates with Gag at the contact zone between infected and target cells, but does not prevent the formation of virological synapses. In the presence of tetherin, viruses are then mostly transferred to targets as abnormally large patches. These viral aggregates do not efficiently promote infection after transfer, because they accumulate at the surface of target cells and are impaired in their fusion capacities. Tetherin, by imprinting virions in donor cells, is the first example of a surface restriction factor limiting viral cell-to-cell spread.

Immunophenotyping of circulating T cells in a mucosal leishmaniasis patient coinfected with HIV

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Lúcio Roberto Castellano

2011-08-01

Full Text Available HIV coinfection modifies the clinical course of leishmaniasis by promoting a Th2 pattern of cytokine production. However, little information is available regarding the lymphocytic response in untreated coinfected patients. This work presents the immunophenotyping of Leishmania-stimulated T cells from a treatment-naÏve HIV+ patient with ML. Leishmania braziliensis antigens induced CD69 expression on CD3+CD4+ and CD3+CD8+ cells. It also increased IL-4 intracellular staining on CD3+CD4+GATA3- population and decreased the percentage of CD3+CD4+IL-17+ cells. This suggests that modulations in the IL-4R/STAT6 pathway and the Th17 population may serve as parasitic evasion mechanisms in HIV/ML. Further studies are required to confirm these results.

T-cell responses targeting HIV Nef uniquely correlate with infected cell frequencies after long-term antiretroviral therapy.

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Allison S Thomas

2017-09-01

Full Text Available HIV-specific CD8+ T-cell responses limit viral replication in untreated infection. After the initiation of antiretroviral therapy (ART, these responses decay and the infected cell population that remains is commonly considered to be invisible to T-cells. We hypothesized that HIV antigen recognition may persist in ART-treated individuals due to low-level or episodic protein expression. We posited that if persistent recognition were occurring it would be preferentially directed against the early HIV gene products Nef, Tat, and Rev as compared to late gene products, such as Gag, Pol, and Env, which have higher barriers to expression. Using a primary cell model of latency, we observed that a Nef-specific CD8+ T-cell clone exhibited low-level recognition of infected cells prior to reactivation and robust recognition shortly thereafter. A Gag-specific CD8+ T-cell clone failed to recognized infected cells under these conditions, corresponding with a lack of detectable Gag expression. We measured HIV-specific T-cell responses in 96 individuals who had been suppressed on ART for a median of 7 years, and observed a significant, direct correlation between cell-associated HIV DNA levels and magnitudes of IFN-γ-producing Nef/Tat/Rev-specific T-cell responses. This correlation was confirmed in an independent cohort (n = 18. Correlations were not detected between measures of HIV persistence and T-cell responses to other HIV antigens. The correlation with Nef/Tat/Rev-specific T-cells was attributable to Nef-specific responses, the breadth of which also correlated with HIV DNA levels. These results suggest that ongoing Nef expression in ART-treated individuals drives preferential maintenance and/or expansion of T-cells reactive to this protein, implying sensing of infected cells by the immune system. The direct correlation, however, suggests that recognition does not result in efficient elimination of infected cells. These results raise the possibility that

Serological response to Epstein-Barr virus early antigen is ...

African Journals Online (AJOL)

Serological response to Epstein-Barr virus early antigen is associated with gastric cancer and human immunodeficiency virus infection in Zambian adults: a ... EBV exposure is common among Zambian adults and that EBV EA seropositivity is associated with gastric cancer and HIV infection, but not premalignant lesions.

Production of a DNA Vaccine Specific for the 64 kDa Protective Antigen of Erysipelothrix rhusiopathiae

National Research Council Canada - National Science Library

Middlebrooks, Bobby L

2007-01-01

The gene for the protective antigen of E. rhusiopathiae will be inserted into a eukaryotic vector both for the production of a DNA vaccine and for large scale production of the recombinant protein (in vitro...

[Efficacy of sweat-antigen-inactivating skin care products on itching of patients with atopic dermatitis].

Science.gov (United States)

Shindo, Hajime; Takahagi, Shunsuke; Mihara, Shoji; Tanaka, Toshihiko; Ishii, Kaori; Hide, Michihiro; Suzuki, Shigeru; Kanatani, Hirotoshi; Yano, Shingo

2011-01-01

Many patients with atopic dermatitis showed immediate-type hypersensitivity against sweat antigen. Therefore, to deal with sweating is important to prevent itching and aggravations of dermatitis of patient with atopic dermatitis. We had searched a substance that inactivated sweat antigen adopting histamine release test. And we found that tannic acid which selected by screening various natural products inactivated sweat antigen. We evaluate skin care products (spray, after-bathing water and aerosol-spray) containing tannic acid for patients with atopic dermatitis. We administered in a tannic acid-containing spray and after-bathing water on 17 patients with atopic dermatitis. After treatment, total clinical assessment score and itching in the afternoon had significantly decreased from that on day 0. To evaluate the effect of tannic acid containing-aerosol spray on itching of patients with AD, we assessed symptoms of atopic dermatitis patients who used a tannic acid containing-aerosol spray every day for 4 weeks in a cross-over, double-blind study. Clinical severity of atopic dermatitis and degrees of itching in daily life of patients were evaluated by physicians and patients themselves, respectively. Degrees of itching in morning and those at night were significantly more largely improved by the use of tannic acid-containing aerosol spray than those by the use of placebo control aerosol spray. The overall efficacy of tannic acid-containing aerosol sprays was also significantly higher than those of tannic acid free spray. Sweat antigen inactivating skin care products may be effective to reduce itching of patients with atopic dermatitis.

Evaluation of HIV antigen /antibody combination ELISAs for ...

African Journals Online (AJOL)

Results: a total of 600 blood samples were included in the evaluation. ... as an alternative confirmatory testing strategy for screening of donated blood at the National and Zonal blood transfusion centres and in lab diagnosis of HIV infection.

Seroprevalence of anti-HCV and hepatitis B surface antigen in HIV infected patients

Directory of Open Access Journals (Sweden)

Tankhiwale S

2003-01-01

Full Text Available Human immunodeficiency virus (HIV is known to influence the natural history of infections with certain hepatitis viruses and interactions between HIV and hepatitis viruses may potentiate HIV replication. There is high degree of epidemiological similarity between hepatitis B virus and HIV as regard to high-risk group and route of transmission. Transmission of hepatitis C virus (HCV through blood transfusion and intravenous drug abuse is well documented. Present study deals with the study of concurrent infection of HBV and HCV with HIV infection. In the study of 110 HIV seropositive patients, 34(30.4% were positive for HBV and 8(7.27% for HCV. The difference of concomitant infection was highly significant compared to controls. (p value < 0.0001. Heterosexual high risk behaviour was observed in 89(80.91% of 110 HIV positive patients, out of which 23(25.8% and 5(5.62% were HBsAg and anti-HCV positive respectively. History of transmission was unclear in remaining patients. Concomitant infection of HIV and HBV was found to be significantly more in the symptomatic group (40.68% compared to asymptomatic group (19.6%. As HIV infection is known to affect the natural history of both HBV and HCV infection, screening of their concurrent association is necessary.

Sequence similarity between the erythrocyte binding domain 1 of the Plasmodium vivax Duffy binding protein and the V3 loop of HIV-1 strain MN reveals binding residues for the Duffy Antigen Receptor for Chemokines

OpenAIRE

Bolton, Michael J; Garry, Robert F

2011-01-01

Abstract Background The surface glycoprotein (SU, gp120) of the human immunodeficiency virus (HIV) must bind to a chemokine receptor, CCR5 or CXCR4, to invade CD4+ cells. Plasmodium vivax uses the Duffy Binding Protein (DBP) to bind the Duffy Antigen Receptor for Chemokines (DARC) and invade reticulocytes. Results Variable loop 3 (V3) of HIV-1 SU and domain 1 of the Plasmodium vivax DBP share a sequence similarity. The site of amino acid sequence similarity was necessary, but not sufficient, ...

Slow progression of paediatric HIV disease: Selective adaptation or ...

African Journals Online (AJOL)

In the European Caucasian populations, the chemokine-cell receptor variant CCR5 \\"Delta 32\\" is a the genetic determinant of HIV disease progression that is believed to have been selected for in the general population by exposure to antigens closely interlinked to HIV like Yersinia pestis or small pox virus. Among African ...

Progress towards development of an HIV vaccine: report of the AIDS Vaccine 2009 Conference.

Science.gov (United States)

Ross, Anna Laura; Bråve, Andreas; Scarlatti, Gabriella; Manrique, Amapola; Buonaguro, Luigi

2010-05-01

The search for an HIV/AIDS vaccine is steadily moving ahead, generating and validating new concepts in terms of novel vectors for antigen delivery and presentation, new vaccine and adjuvant strategies, alternative approaches to design HIV-1 antigens for eliciting protective cross-neutralising antibodies, and identification of key mechanisms in HIV infection and modulation of the immune system. All these different perspectives are contributing to the unprecedented challenge of developing a protective HIV-1 vaccine. The high scientific value of this massive effort is its great impact on vaccinology as a whole, providing invaluable scientific information for the current and future development of new preventive vaccine as well as therapeutic knowledge-based infectious-disease and cancer vaccines. Copyright 2010 Elsevier Ltd. All rights reserved.

Tuberculosis, hepatitis C and hepatitis B co-infections in patients with HIV in the Great Tehran Prison, Iran

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Behnam Farhoudi

2016-01-01

Full Text Available We conducted a study to evaluate tuberculosis (TB, hepatitis C and hepatitis B co-infections in male patients with HIV in the Great Tehran Prison from October 2013 to May 2014. Among 85 HIV positive patients, five persons (5.9% had TB. Also, 56 new HIV-infected patients were checked for hepatitis B surface antigen and hepatitis C virus antibody. There were three hepatitis B surface antigen (5.4% and 50 hepatitis C virus antibody (89.3% results. This study suggests that it is necessary to investigate TB, hepatitis C and hepatitis B in HIV positive prisoners in Iran.

Artificial 64-Residue HIV-1 Enhancer-Binding Peptide Is a Potent Inhibitor of Viral Replication in HIV-1-Infected Cells.

Science.gov (United States)

Oufir, Mouhssin; Bisset, Leslie R; Hoffmann, Stefan R K; Xue, Gongda; Klauser, Stephan; Bergamaschi, Bianca; Gervaix, Alain; Böni, Jürg; Schüpbach, Jörg; Gutte, Bernd

2011-01-01

An artificial HIV-1 enhancer-binding peptide was extended by nine consecutive arginine residues at the C-terminus and by the nuclear localization signal of SV40 large T antigen at the N-terminus. The resulting synthetic 64-residue peptide was found to bind to the two enhancers of the HIV-1 long terminal repeat, cross the plasma membrane and the nuclear envelope of human cells, and suppress the HIV-1 enhancer-controlled expression of a green fluorescent protein reporter gene. Moreover, HIV-1 replication is inhibited by this peptide in HIV-1-infected CEM-GFP cells as revealed by HIV-1 p24 ELISA and real-time RT-PCR of HIV-1 RNA. Rapid uptake of this intracellular stable and inhibitory peptide into the cells implies that this peptide may have the potential to attenuate HIV-1 replication in vivo.

Homology-Directed Recombination for Enhanced Engineering of Chimeric Antigen Receptor T Cells

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Malika Hale

2017-03-01

Full Text Available Gene editing by homology-directed recombination (HDR can be used to couple delivery of a therapeutic gene cassette with targeted genomic modifications to generate engineered human T cells with clinically useful profiles. Here, we explore the functionality of therapeutic cassettes delivered by these means and test the flexibility of this approach to clinically relevant alleles. Because CCR5-negative T cells are resistant to HIV-1 infection, CCR5-negative anti-CD19 chimeric antigen receptor (CAR T cells could be used to treat patients with HIV-associated B cell malignancies. We show that targeted delivery of an anti-CD19 CAR cassette to the CCR5 locus using a recombinant AAV homology template and an engineered megaTAL nuclease results in T cells that are functionally equivalent, in both in vitro and in vivo tumor models, to CAR T cells generated by random integration using lentiviral delivery. With the goal of developing off-the-shelf CAR T cell therapies, we next targeted CARs to the T cell receptor alpha constant (TRAC locus by HDR, producing TCR-negative anti-CD19 CAR and anti-B cell maturation antigen (BCMA CAR T cells. These novel cell products exhibited in vitro cytolytic activity against both tumor cell lines and primary cell targets. Our combined results indicate that high-efficiency HDR delivery of therapeutic genes may provide a flexible and robust method that can extend the clinical utility of cell therapeutics.

Improved protection conferred by vaccination with a recombinant vaccinia virus that incorporates a foreign antigen into the extracellular enveloped virion

International Nuclear Information System (INIS)

Kwak, Heesun; Mustafa, Waleed; Speirs, Kendra; Abdool, Asha J.; Paterson, Yvonne; Isaacs, Stuart N.

2004-01-01

Recombinant poxviruses have shown promise as vaccine vectors. We hypothesized that improved cellular immune responses could be developed to a foreign antigen by incorporating it as part of the extracellular enveloped virion (EEV). We therefore constructed a recombinant vaccinia virus that replaced the cytoplasmic domain of the B5R protein with a test antigen, HIV-1 Gag. Mice immunized with the virus expressing Gag fused to B5R had significantly better primary CD4 T-cell responses than recombinant virus expressing HIV-Gag from the TK-locus. The CD8 T-cell responses were less different between the two groups. Importantly, although we saw differences in the immune response to the test antigen, the vaccinia virus-specific immune responses were similar with both constructs. When groups of vaccinated mice were challenged 30 days later with a recombinant Listeria monocytogenes that expresses HIV-Gag, mice inoculated with the virus that expresses the B5R-Gag fusion protein had lower colony counts of Listeria in the liver and spleen than mice vaccinated with the standard recombinant. Thus, vaccinia virus expressing foreign antigen incorporated into EEV may be a better vaccine strategy than standard recombinant vaccinia virus

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

A DEAD box protein facilitates HIV-1 replication as a cellular co-factor of Rev

International Nuclear Information System (INIS)

Fang Jianhua; Kubota, Satoshi; Yang Bin; Zhou Naiming; Zhang Hui; Godbout, Roseline; Pomerantz, Roger J.

2004-01-01

HIV-1 Rev escorts unspliced viral mRNAs out of the nucleus of infected cells, which allows formation of infectious HIV-1 virions. We have identified a putative DEAD box (Asp-Glu-Ala-Asp) RNA helicase, DDX1, as a cellular co-factor of Rev, through yeast and mammalian two-hybrid systems using the N-terminal motif of Rev as 'bait'. DDX1 is not a functional homolog of HIV-1 Rev, but down-regulation of DDX1 resulted in an alternative splicing pattern of Rev-responsive element (RRE)-containing mRNA, and attenuation of Gag p24 antigen production from HLfb rev(-) cells rescued by exogenous Rev. Co-transfection of a DDX1 expression vector with HIV-1 significantly increased viral production. DDX1 binding to Rev, as well as to the RRE, strongly suggest that DDX1 affects Rev function through the Rev-RRE axis. Moreover, down-regulation of DDX1 altered the steady state subcellular distribution of Rev, from nuclear/nucleolar to cytoplasmic dominance. These findings indicate that DDX1 is a critical cellular co-factor for Rev function, which maintains the proper subcellular distribution of this lentiviral regulatory protein. Therefore, alterations in DDX1-Rev interactions could induce HIV-1 persistence and targeting DDX1 may lead to rationally designed and novel anti-HIV-1 strategies and therapeutics

Monoclonal Antibody Production against Human Spermatozoal Surface Antigens

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M Jedi-Tehrani

2005-10-01

Full Text Available Introduction: As monoclonal antibodies are potential tools for characterization of soluble or cellular surface antigens, use of these proteins has always been considered in infertility and reproduction research. Therefore, in this study, monoclonal antibodies against human sperm surface antigens were produced. Material and Methods: To produce specific clones against human sperm surface antigens, proteins were extracted using solubilization methods. Balb/c mice were immunized intraperitoneally with the proteins using complete Freund’s adjuvant in the first injection and incomplete Adjuvant in the following booster injections. Hybridoma cells producing ASA were cloned by limiting dilution. Results: Five stable ASA producing hybridoma clones were achieved and their antibody isotypes were determined by ELISA. All the isotypes were of IgG class. Their cross reactivity with rat and mice spermatozoa was examined but they did not have any cross reactivity. Conclusion: The produced antibodies can be used in further studies to characterize and evaluate each of the antigens present on human sperm surface and determining their role in fertilization.

Seroprevalence occurrence of viral hepatitis and HIV among hemodialysis patients

Science.gov (United States)

Kamal, Inass Mahmood; Mutar Mahdi, Batool

2018-05-01

Background: Patients with chronic renal failure (CRF) were on maintenance invasive haemodialysis (HD) procedure. This procedure by itself affects immunity of the patients and became more susceptible to viral infections. Aim of the study: to investigate the occurrence of HBV, HCV and HIV infections in patients with hemodialysis. Patients and methods: A retrospective study of 430 end-stage renal failure patients, referred to hemodialysis department at Al-Kindy Teaching Hospital, Baghdad-Iraq from Junuary-2015 to Junuary-2017. Patients were investigated for HBs-Ag using enzyme-labeled antigen test (Foresight-EIA-USA ), HCV- Abs (IgG) specific immunoglobulin using a HCV enzyme-labeled antigen test (Foresight-EIA-USA) and anti HIV Abs (IgG) using enzyme-labeled antigen test (Foresight-EIA-USA). Results: The frequency of HBV infection in the first year was not significant between males (1.11%) and females (0.00%)(P = 0.295). About HCV also there are no significant differences between males (12.63%) and females (9.31%)(P = 0.347). After one year of follow up the frequencies of HBV and HCV were not significant between two sexes. Additionally, no any one of the patients had HIV infection. Conclusions: This study brings a light on that HBV and HCV were having the same frequencies in both genders and lower occurrence with time. Furthermore, HIV was not detected in those patients.

Seroprevalence occurrence of viral hepatitis and HIV among hemodialysis patients.

Science.gov (United States)

Kamal, Inass Mahmood Abid; Mahdi, Batool Mutar

2018-05-01

Patients with chronic renal failure (CRF) were on maintenance invasive hemodialysis (HD) procedure. This procedure by itself affects immunity of the patients and became more susceptible to viral infections. to investigate the occurrence of HBV, HCV and HIV infections in patients with hemodialysis. A retrospective study of 430 end-stage renal failure patients, referred to hemodialysis department at XXXX Teaching Hospital, Baghdad-Iraq from January-2015 to January-2017. Patients were investigated for HBs-Ag using enzyme-labeled antigen test (Foresight-EIA-USA), HCV- Abs (IgG) specific immunoglobulin using an HCV enzyme-labeled antigen test (Foresight-EIA-USA)and anti - HIV Abs (IgG) using enzyme-labeled antigen test (Foresight-EIA-USA). The frequency of HBV infection in the first year was not significant between males (1.11%) and females (0.00%) (P = 0.295). About HCV also there are no significant differences between males (12.63%) and females (9.31%) (P = 0.347). After one year of follow up the frequencies of HBV and HCV were not significant between two sexes. Additionally, no any one of the patients had HIV infection. This study brings a light on that HBV and HCV were having the same frequencies in both genders and lower occurrence with time. Furthermore, HIV was not detected in those patients.

Artificial 64-Residue HIV-1 Enhancer-Binding Peptide Is a Potent Inhibitor of Viral Replication in HIV-1-Infected Cells

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Mouhssin Oufir

2011-01-01

Full Text Available An artificial HIV-1 enhancer-binding peptide was extended by nine consecutive arginine residues at the C-terminus and by the nuclear localization signal of SV40 large T antigen at the N-terminus. The resulting synthetic 64-residue peptide was found to bind to the two enhancers of the HIV-1 long terminal repeat, cross the plasma membrane and the nuclear envelope of human cells, and suppress the HIV-1 enhancer-controlled expression of a green fluorescent protein reporter gene. Moreover, HIV-1 replication is inhibited by this peptide in HIV-1-infected CEM-GFP cells as revealed by HIV-1 p24 ELISA and real-time RT-PCR of HIV-1 RNA. Rapid uptake of this intracellular stable and inhibitory peptide into the cells implies that this peptide may have the potential to attenuate HIV-1 replication in vivo.

HDAC inhibition induces HIV-1 protein and enables immune-based clearance following latency reversal

DEFF Research Database (Denmark)

Wu, Guoxin; Swanson, Michael; Talla, Aarthi

2017-01-01

Promising therapeutic approaches for eradicating HIV include transcriptional activation of provirus from latently infected cells using latency-reversing agents (LRAs) and immune-mediated clearance to purge reservoirs. Accurate detection of cells capable of producing viral antigens and virions......, and the measurement of clearance of infected cells, is essential to assessing therapeutic efficacy. Here, we apply enhanced methodology extending the sensitivity limits for the rapid detection of subfemtomolar HIV gag p24 capsid protein in CD4+ T cells from ART-suppressed HIV+ individuals, and we show viral protein...... induction following treatment with LRAs. Importantly, we demonstrate that clinical administration of histone deacetylase inhibitors (HDACis; vorinostat and panobinostat) induced HIV gag p24, and ex vivo stimulation produced sufficient viral antigen to elicit immune-mediated cell killing using anti-gp120/CD3...

Knowledge and acceptability of alternative HIV prevention bio-medical products among MSM who bareback.

Science.gov (United States)

Nodin, N; Carballo-Diéguez, A; Ventuneac, A M; Balan, I C; Remien, R

2008-01-01

Condom use is the best available strategy to prevent HIV infection during sexual intercourse. However, since many people choose not to use condoms in circumstances in which HIV risk exists, alternatives to condom use for HIV prevention are needed. Currently there are several alternative bio-medical HIV-prevention products in different stages of development: microbicides, vaccines, post-exposure prophylaxis (PEP) and pre-exposure prophylaxis (PrEP). Seventy-two men who have sex with men (MSM) who took part in a study on Internet use and intentional condomless anal intercourse were asked about these four products during a semi-structured interview. The questions explored knowledge and acceptability of all the products and willingness to participate in microbicide and vaccine trials. Qualitative analysis of the data suggests that these men had virtually no knowledge of PrEP, very limited knowledge of microbicides, some information about PEP and considerably more knowledge about vaccines. Reactions towards the products were generally positive except for PrEP, for which reactions were polarized as either enthusiastic or negative. With the exception of PrEP, many men expressed willingness to use the products in the future. Most men would be willing to participate in trials for microbicides and vaccines if given basic reassurances. Concerns over negative side effects and preoccupation with possible infection were some of the motives given for non-willingness to participate in a vaccine trial. These results should inform the development of future trials of biomedical prevention products.

Antigen-Specific Interferon-Gamma Responses and Innate Cytokine Balance in TB-IRIS

NARCIS (Netherlands)

Goovaerts, Odin; Jennes, Wim; Massinga-Loembé, Marguerite; Ceulemans, Ann; Worodria, William; Mayanja-Kizza, Harriet; Colebunders, Robert; Kestens, Luc; Loembé, Marguerite Massinga; Mayanja, Harriet; Mascart, Francoise; van den Bergh, Rafael; Locht, Camille; Reiss, Peter; Cobelens, Frank; Ondoa, Pascale; Pakker, Nadine; Mugerwa, Roy

2014-01-01

Background: Tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) remains a poorly understood complication in HIV-TB patients receiving antiretroviral therapy (ART). TB-IRIS could be associated with an exaggerated immune response to TB-antigens. We compared the recovery of

A High Frequency of HIV-Specific Circulating Follicular Helper T Cells Is Associated with Preserved Memory B Cell Responses in HIV Controllers.

Science.gov (United States)

Claireaux, M; Galperin, M; Benati, D; Nouël, A; Mukhopadhyay, M; Klingler, J; de Truchis, P; Zucman, D; Hendou, S; Boufassa, F; Moog, C; Lambotte, O; Chakrabarti, L A

2018-05-08

Follicular helper T cells (Tfh) play an essential role in the affinity maturation of the antibody response by providing help to B cells. To determine whether this CD4 + T cell subset may contribute to the spontaneous control of HIV infection, we analyzed the phenotype and function of circulating Tfh (cTfh) in patients from the ANRS CO21 CODEX cohort who naturally controlled HIV-1 replication to undetectable levels and compared them to treated patients with similarly low viral loads. HIV-specific cTfh (Tet + ), detected by Gag-major histocompatibility complex class II (MHC-II) tetramer labeling in the CD45RA - CXCR5 + CD4 + T cell population, proved more frequent in the controller group ( P = 0.002). The frequency of PD-1 expression in Tet + cTfh was increased in both groups (median, >75%) compared to total cTfh (<30%), but the intensity of PD-1 expression per cell remained higher in the treated patient group ( P = 0.02), pointing to the persistence of abnormal immune activation in treated patients. The function of cTfh, analyzed by the capacity to promote IgG secretion in cocultures with autologous memory B cells, did not show major differences between groups in terms of total IgG production but proved significantly more efficient in the controller group when measuring HIV-specific IgG production. The frequency of Tet + cTfh correlated with HIV-specific IgG production ( R = 0.71 for Gag-specific and R = 0.79 for Env-specific IgG, respectively). Taken together, our findings indicate that key cTfh-B cell interactions are preserved in controlled HIV infection, resulting in potent memory B cell responses that may play an underappreciated role in HIV control. IMPORTANCE The rare patients who spontaneously control HIV replication in the absence of therapy provide a unique model to identify determinants of an effective anti-HIV immune response. HIV controllers show signs of particularly efficient antiviral T cell responses, while their humoral response was until recently

Immune defence against HIV-1 infection in HIV-1-exposed seronegative persons.

Science.gov (United States)

Schmechel, S C; Russell, N; Hladik, F; Lang, J; Wilson, A; Ha, R; Desbien, A; McElrath, M J

2001-11-01

Rare individuals who are repeatedly exposed to HIV-1 through unprotected sexual contact fail to acquire HIV-1 infection. These persons represent a unique study population to evaluate mechanisms by which HIV-1 replication is either prevented or controlled. We followed longitudinally a group of healthy HIV-1 seronegative persons each reporting repeated high-risk sexual activities with their HIV-1-infected partner at enrollment. The volunteers were primarily (90%) male homosexuals, maintaining high risk activities with their known infected partner (45%) or multiple other partners (61%). We evaluated the quantity and specificity of HIV-1-specific T cells in 31 exposed seronegatives (ES) using a IFN-gamma ELISPOT assay to enumerate T cells recognizing epitopes within HIV-1 Env, Gag, Pol and Nef. PBMC from only three of the 31 volunteers demonstrated ex vivo HIV-1-specific IFN-gamma secretion, in contrast to nearly 30% exhibiting cytolytic responses in previous studies. These findings suggest that if T cell responses in ES are induced by HIV-1 exposure, the frequency is at low levels in most of them, and below the level of detection using the ELISPOT assay. Alternative approaches to improve the sensitivity of detection may include use of dendritic cells as antigen-presenting cells in the ex vivo assay and more careful definition of the risk behavior and extent of HIV-1 exposure in conjunction with the evaluation of T cell responses.

HIV/AIDS influences blood and blood product use at Groote Schuur ...

African Journals Online (AJOL)

HIV/AIDS influences blood and blood product use at Groote Schuur Hospital, Cape Town. NBA Ntusi, MW Sonderup. Abstract. Background. Use of blood and blood products in the medical wards at Groote Schuur Hospital, Cape Town, has increased substantially and significantly increased expenditure. It was suspected that ...

Production and purification of immunologically active core protein p24 from HIV-1 fused to ricin toxin B subunit in E. coli

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Gómez-Lim Miguel A

2009-02-01

Full Text Available Abstract Background Gag protein from HIV-1 is a polyprotein of 55 kDa, which, during viral maturation, is cleaved to release matrix p17, core p24 and nucleocapsid proteins. The p24 antigen contains epitopes that prime helper CD4 T-cells, which have been demonstrated to be protective and it can elicit lymphocyte proliferation. Thus, p24 is likely to be an integral part of any multicomponent HIV vaccine. The availability of an optimal adjuvant and carrier to enhance antiviral responses may accelerate the development of a vaccine candidate against HIV. The aim of this study was to investigate the adjuvant-carrier properties of the B ricin subunit (RTB when fused to p24. Results A fusion between ricin toxin B subunit and p24 HIV (RTB/p24 was expressed in E. coli. Affinity chromatography was used for purification of p24 alone and RTB/p24 from cytosolic fractions. Biological activity of RTB/p24 was determined by ELISA and affinity chromatography using the artificial receptor glycoprotein asialofetuin. Both assays have demonstrated that RTB/p24 is able to interact with complex sugars, suggesting that the chimeric protein retains lectin activity. Also, RTB/p24 was demonstrated to be immunologically active in mice. Two weeks after intraperitoneal inoculation with RTB/p24 without an adjuvant, a strong anti-p24 immune response was detected. The levels of the antibodies were comparable to those found in mice immunized with p24 alone in the presence of Freund adjuvant. RTB/p24 inoculated intranasally in mice, also elicited significant immune responses to p24, although the response was not as strong as that obtained in mice immunized with p24 in the presence of the mucosal adjuvant cholera toxin. Conclusion In this work, we report the expression in E. coli of HIV-1 p24 fused to the subunit B of ricin toxin. The high levels of antibodies obtained after intranasal and intraperitoneal immunization of mice demonstrate the adjuvant-carrier properties of RTB when

Prime-Boost Vaccination Using Chemokine-Fused gp120 DNA and HIV Envelope Peptides Activates Both Immediate and Long-Term Memory Cellular Responses in Rhesus Macaques

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Hong Qin

2010-01-01

Full Text Available HIV vaccine candidates with improved immunogenicity and induction of mucosal T-cell immunity are needed. A prime-boost strategy using a novel HIV glycoprotein 120 DNA vaccine was employed to immunize rhesus macaques. The DNA vaccine encoded a chimeric gp120 protein in fusion with monocyte chemoattractant protein-3, which was hypothesized to improve the ability of antigen-presenting cells to capture viral antigen through chemokine receptor-mediated endocytosis. DNA vaccination induced virus-reactive T cells in peripheral blood, detectable by T cell proliferation, INFγ ELISPOT and sustained IL-6 production, without humoral responses. With a peptide-cocktail vaccine containing a set of conserved polypeptides of HIV-1 envelope protein, given by nasogastric administration, primed T-cell immunity was significantly boosted. Surprisingly, long-term and peptide-specific mucosal memory T-cell immunity was detected in both vaccinated macaques after one year. Therefore, data from this investigation offer proof-of-principle for potential effectiveness of the prime-boost strategy with a chemokine-fused gp120 DNA and warrant further testing in the nonhuman primate models for developing as a potential HIV vaccine candidate in humans.

Dynamics of antigen presentation to transgene product-specific CD4+ T cells and of Treg induction upon hepatic AAV gene transfer

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George Q Perrin

2016-01-01

Full Text Available The tolerogenic hepatic microenvironment impedes clearance of viral infections but is an advantage in viral vector gene transfer, which often results in immune tolerance induction to transgene products. Although the underlying tolerance mechanism has been extensively studied, our understanding of antigen presentation to transgene product-specific CD4+ T cells remains limited. To address this, we administered hepatotropic adeno-associated virus (AAV8 vector expressing cytoplasmic ovalbumin (OVA into wt mice followed by adoptive transfer of transgenic OVA-specific T cells. We find that that the liver-draining lymph nodes (celiac and portal are the major sites of MHC II presentation of the virally encoded antigen, as judged by in vivo proliferation of DO11.10 CD4+ T cells (requiring professional antigen-presenting cells, e.g., macrophages and CD4+CD25+FoxP3+ Treg induction. Antigen presentation in the liver itself contributes to activation of CD4+ T cells egressing from the liver. Hepatic-induced Treg rapidly disseminate through the systemic circulation. By contrast, a secreted OVA transgene product is presented in multiple organs, and OVA-specific Treg emerge in both the thymus and periphery. In summary, liver draining lymph nodes play an integral role in hepatic antigen presentation and peripheral Treg induction, which results in systemic regulation of the response to viral gene products.

Optimization of a multi-gene HIV-1 recombinant subtype CRF02AG DNA vaccine for expression of multiple immunogenic forms

International Nuclear Information System (INIS)

Ellenberger, Dennis; Li Bin; Smith, James; Yi Hong; Folks, Thomas; Robinson, Harriet; Butera, Salvatore

2004-01-01

We developed an AIDS vaccine for Western and West-Central Africa based on a DNA plasmid vector expressing HIV-1 recombinant subtype CRF02 A G gag, pol, and env genes. To optimize the production of noninfectious HIV-like particles (VLPs) and potentially improve the effectiveness of the vaccine, we generated four potential vaccine constructs: the parental (IC2) and three modifications (IC25, IC48, and IC90) containing mutations within the HIV protease. While the parental construct IC2 expressed aggregates of Gag proteins, the IC25 construct resulted in the production of immature VLPs (the core comprises unprocessed Pr 55Gag ). The remaining two constructs (IC48 and IC90) produced mature VLPs (the core comprises processed capsid p24) in addition to immature VLPs and aggregates of Gag proteins. VLPs incorporated significant levels of mature gp120 envelope glycoprotein. Importantly, the mature VLPs were fusion competent and entered coreceptor-specific target cells. The production of multiple antigenic forms, including fusion-competent VLPs, by candidate DNA vaccine constructs may provide immunologic advantages for induction of protective cellular and humoral responses against HIV-1 proteins

Towards biocompatible vaccine delivery systems: interactions of colloidal PECs based on polysaccharides with HIV-1 p24 antigen.

Science.gov (United States)

Drogoz, Alexandre; Munier, Séverine; Verrier, Bernard; David, Laurent; Domard, Alain; Delair, Thierry

2008-02-01

This work reports on the interactions of a model protein (p24, the capside protein of HIV-1 virus) with colloids obtained from polyelectrolyte complexes (PECs) involving two polysaccharides: chitosan and dextran sulfate (DS). The PECs were elaborated by a one-shot addition of default amounts of one counterpart to the polymer in excess. Depending on the nature of the excess polyelectrolyte, the submicrometric colloid was either positively or negatively charged. HIV-1 capsid p24 protein was chosen as antigen, the ultrapure form, lipopolysaccharide-free (endotoxin-, vaccine grade) was used in most experiments, as the level of purity of the protein had a great impact on the immobilization process. p24 sorption kinetics, isotherms, and loading capacities were investigated for positively and negatively charged particles of chitosans and dextran sulfates differing in degrees of polymerization (DP) or acetylation (DA). Compared with the positive particles, negatively charged colloids had higher binding capacities, faster kinetics, and a better stability of the adsorbed p24. Capacities up to 600 mg x g(-1) (protein-colloid) were obtained, suggesting that the protein interacted within the shell of the particles. Small-angle X-rays scattering experiments confirmed this hypothesis. Finally, the immunogenicity of the p24-covered particles was assessed for vaccine purposes in mice. The antibody titers obtained with immobilized p24 was dose dependent and in the same range as for Freund's adjuvant, a gold standard for humoral responses.

Improved innate and adaptive immunostimulation by genetically modified HIV-1 protein expressing NYVAC vectors.

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Esther D Quakkelaar

Full Text Available Attenuated poxviruses are safe and capable of expressing foreign antigens. Poxviruses are applied in veterinary vaccination and explored as candidate vaccines for humans. However, poxviruses express multiple genes encoding proteins that interfere with components of the innate and adaptive immune response. This manuscript describes two strategies aimed to improve the immunogenicity of the highly attenuated, host-range restricted poxvirus NYVAC: deletion of the viral gene encoding type-I interferon-binding protein and development of attenuated replication-competent NYVAC. We evaluated these newly generated NYVAC mutants, encoding HIV-1 env, gag, pol and nef, for their ability to stimulate HIV-specific CD8 T-cell responses in vitro from blood mononuclear cells of HIV-infected subjects. The new vectors were evaluated and compared to the parental NYVAC vector in dendritic cells (DCs, RNA expression arrays, HIV gag expression and cross-presentation assays in vitro. Deletion of type-I interferon-binding protein enhanced expression of interferon and interferon-induced genes in DCs, and increased maturation of infected DCs. Restoration of replication competence induced activation of pathways involving antigen processing and presentation. Also, replication-competent NYVAC showed increased Gag expression in infected cells, permitting enhanced cross-presentation to HIV-specific CD8 T cells and proliferation of HIV-specific memory CD8 T-cells in vitro. The recombinant NYVAC combining both modifications induced interferon-induced genes and genes involved in antigen processing and presentation, as well as increased Gag expression. This combined replication-competent NYVAC is a promising candidate for the next generation of HIV vaccines.

T Follicular Helper Cells and B Cell Dysfunction in Aging and HIV-1 Infection.

Science.gov (United States)

Pallikkuth, Suresh; de Armas, Lesley; Rinaldi, Stefano; Pahwa, Savita

2017-01-01

T follicular helper (Tfh) cells are a subset of CD4 T cells that provide critical signals to antigen-primed B cells in germinal centers to undergo proliferation, isotype switching, and somatic hypermutation to generate long-lived plasma cells and memory B cells during an immune response. The quantity and quality of Tfh cells therefore must be tightly controlled to prevent immune dysfunction in the form of autoimmunity and, on the other hand, immune deficiency. Both Tfh and B cell perturbations appear during HIV infection resulting in impaired antibody responses to vaccines such as seasonal trivalent influenza vaccine, also seen in biologic aging. Although many of the HIV-associated defects improve with antiretroviral therapy (ART), excess immune activation and antigen-specific B and T cell responses including Tfh function are still impaired in virologically controlled HIV-infected persons on ART. Interestingly, HIV infected individuals experience increased risk of age-associated pathologies. This review will discuss Tfh and B cell dysfunction in HIV infection and highlight the impact of chronic HIV infection and aging on Tfh-B cell interactions.

Antigen processing influences HIV-specific cytotoxic T lymphocyte immunodominance

DEFF Research Database (Denmark)

Tenzer, Stefan; Wee, Edmund; Burgevin, Anne

2009-01-01

-associated antigen proteins p17 and p24 correlated with epitope abundance, which was strongly influenced by proteasomal digestion profiles, affinity for the transporter protein TAP, and trimming mediated by the endoplasmatic reticulum aminopeptidase ERAAP, and was moderately influenced by HLA affinity. Structural...

HIV/AIDS in childhood and adolescence. Trends in Brazilian scientific production

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Cristiane Cardoso de Paula

2013-07-01

Full Text Available Objective. To analyze the theme HIV/AIDS in childhood and adolescence, its characteristics and trends, in Brazilian scientific production between 1983 and 2010. Methodology. Review of 121 quantitative and qualitative descriptive studies. Results. 81% of the production comes from the South-East/South of the country. In the 1980's, a balance is observed between experience reports (50% and research (50%. Seventy percent of the papers were produced between 2003 and 2010. The most frequent theme analyzed with regard to childhood was care delivery (75%, against prevention in adolescence (72%. Studies related to HIV/ AIDS in emphasized clinical-epidemiological aspects (70%, while sociocultural studies predominated for the adolescent period (90%, with a preventive trend. Conclusion. The scientific production under analysis is coherent with the Brazilian policy to cope with the epidemic and addresses all care levels related to this public health problem.

Overview of Plant-Made Vaccine Antigens against Malaria

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Marina Clemente

2012-01-01

Full Text Available This paper is an overview of vaccine antigens against malaria produced in plants. Plant-based expression systems represent an interesting production platform due to their reduced manufacturing costs and high scalability. At present, different Plasmodium antigens and expression strategies have been optimized in plants. Furthermore, malaria antigens are one of the few examples of eukaryotic proteins with vaccine value expressed in plants, making plant-derived malaria antigens an interesting model to analyze. Up to now, malaria antigen expression in plants has allowed the complete synthesis of these vaccine antigens, which have been able to induce an active immune response in mice. Therefore, plant production platforms offer wonderful prospects for improving the access to malaria vaccines.

Mycobacterium avium and purified protein derivative-specific cytotoxicity mediated by CD4+ lymphocytes from healthy HIV-seropositive and-seronegative individuals

DEFF Research Database (Denmark)

Ravn, P; Pedersen, B K

1996-01-01

mycobacteria. Our objective was to investigate the M.tuberculosis-and M. avium-specific cytotoxic capacity of T cells from healthy, bacille Calmette-Guérin-vaccinated, HIV-seropositive individuals. Blood mononuclear cells were obtained from 10 healthy HIV-seropositive and 10 healthy seronegative persons...... with no history of previous or active mycobacterial infection. Antigen-specific killing of macrophages presenting mycobacterial antigens (purified protein derivative or M. avium culture filtrate) was conducted. The phenotype of the killer cells was determined by a fluorescence-activated cell sorter after antigen...

Seroprevalence occurrence of viral hepatitis and HIV among hemodialysis patients

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Inass Mahmood Abid Kamal

2018-05-01

Full Text Available Background: Patients with chronic renal failure (CRF were on maintenance invasive hemodialysis (HD procedure. This procedure by itself affects immunity of the patients and became more susceptible to viral infections. Aim of the study: to investigate the occurrence of HBV, HCV and HIV infections in patients with hemodialysis. Patients and methods: A retrospective study of 430 end-stage renal failure patients, referred to hemodialysis department at XXXX Teaching Hospital, Baghdad-Iraq from January-2015 to January-2017. Patients were investigated for HBs-Ag using enzyme-labeled antigen test (Foresight-EIA-USA, HCV- Abs (IgG specific immunoglobulin using an HCV enzyme-labeled antigen test (Foresight-EIA-USAand anti - HIV Abs (IgG using enzyme-labeled antigen test (Foresight-EIA-USA. Results: The frequency of HBV infection in the first year was not significant between males (1.11% and females (0.00% (P = 0.295. About HCV also there are no significant differences between males (12.63% and females (9.31% (P = 0.347. After one year of follow up the frequencies of HBV and HCV were not significant between two sexes. Additionally, no any one of the patients had HIV infection. Conclusions: This study brings a light on that HBV and HCV were having the same frequencies in both genders and lower occurrence with time. Furthermore, HIV was not detected in those patients. Keywords: Virus, Hemodialysis, Infection

Anti-HIV Antibody Responses and the HIV Reservoir Size during Antiretroviral Therapy.

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Sulggi A Lee

Full Text Available A major challenge to HIV eradication strategies is the lack of an accurate measurement of the total burden of replication-competent HIV (the "reservoir". We assessed the association of anti-HIV antibody responses and the estimated size of the reservoir during antiretroviral therapy (ART.We evaluated anti-HIV antibody profiles using luciferase immunoprecipitation systems (LIPS assay in relation to several blood-based HIV reservoir measures: total and 2-LTR DNA (rtPCR or droplet digital PCR; integrated DNA (Alu PCR; unspliced RNA (rtPCR, multiply-spliced RNA (TILDA, residual plasma HIV RNA (single copy PCR, and replication-competent virus (outgrowth assay. We also assessed total HIV DNA and RNA in gut-associated lymphoid tissue (rtPCR. Spearman correlations and linear regressions were performed using log-transformed blood- or tissue-based reservoir measurements as predictors and log-transformed antibody levels as outcome variables.Among 51 chronically HIV-infected ART-suppressed participants (median age = 57, nadir CD4+ count = 196 cells/mm3, ART duration = 9 years, the most statistically significant associations were between antibody responses to integrase and HIV RNA in gut-associated lymphoid tissue (1.17 fold-increase per two-fold RNA increase, P = 0.004 and between antibody responses to matrix and integrated HIV DNA in resting CD4+ T cells (0.35 fold-decrease per two-fold DNA increase, P = 0.003. However, these associations were not statistically significant after a stringent Bonferroni-adjustment of P<0.00045. Multivariate models including age and duration of ART did not markedly alter results.Our findings suggest that anti-HIV antibody responses may reflect the size of the HIV reservoir during chronic treated HIV disease, possibly via antigen recognition in reservoir sites. Larger, prospective studies are needed to validate the utility of antibody levels as a measure of the total body burden of HIV during treatment.

Chlorphenesin: an antigen-associated immunosuppressant.

Science.gov (United States)

Whang, H Y; Neter, E

1970-07-01

Chlorphenesin (3-p-chlorophenoxy-1,2-propanediol), when injected intravenously together with either of two common bacterial antigens, inhibits the antibody response of the rabbit. The antigens studied are those common to Enterobacteriaceae and to gram-positive bacteria. The immunosuppression is contingent upon incubation of chlorphenesin and antigen in vitro prior to administration, since separate injection of antigen and inhibitor or of mixtures without prior incubation yields undiminished antibody response. Chlorphenesin, as shown by hemagglutination-inhibition tests, does not alter the antigenic determinants, because antibody neutralization occurs in the presence or absence of the drug. The immunosuppressive effect is reversible, since precipitation of chlorphenesin at 4 C substantially restores immunogenicity. Animals immunized with antigen-drug mixtures, which fail to respond with significant antibody production, nonetheless are immunologically primed. It is concluded that chlorphenesin represents another example of antigen-associated immunosuppressants.

Astrocytes sustain long-term productive HIV-1 infection without establishment of reactivable viral latency.

Science.gov (United States)

Barat, Corinne; Proust, Alizé; Deshiere, Alexandre; Leboeuf, Mathieu; Drouin, Jean; Tremblay, Michel J

2018-02-21

The "shock and kill" HIV-1 cure strategy proposes eradication of stable cellular reservoirs by clinical treatment with latency-reversing agents (LRAs). Although resting CD4 + T cells latently infected with HIV-1 constitute the main reservoir that is targeted by these approaches, their consequences on other reservoirs such as the central nervous system are still unknown and should be taken into consideration. We performed experiments aimed at defining the possible role of astrocytes in HIV-1 persistence in the brain and the effect of LRA treatments on this viral sanctuary. We first demonstrate that the diminished HIV-1 production in a proliferating astrocyte culture is due to a reduced proliferative capacity of virus-infected cells compared with uninfected astrocytes. In contrast, infection of non-proliferating astrocytes led to a robust HIV-1 infection that was sustained for over 60 days. To identify astrocytes latently infected with HIV-1, we designed a new dual-color reporter virus called NL4.3 eGFP-IRES-Crimson that is fully infectious and encodes for all viral proteins. Although we detected a small fraction of astrocytes carrying silent HIV-1 proviruses, we did not observe any reactivation using various LRAs and even strong inducers such as tumor necrosis factor, thus suggesting that these proviruses were either not transcriptionally competent or in a state of deep latency. Our findings imply that astrocytes might not constitute a latent reservoir per se but that relentless virus production by this brain cell population could contribute to the neurological disorders seen in HIV-1-infected persons subjected to combination antiretroviral therapy. © 2018 Wiley Periodicals, Inc.

78 FR 67175 - Proposed Collection; 60-Day Comment Request: Incident HIV/Hepatitis B Virus Infections in South...

Science.gov (United States)

2013-11-08

... Comment Request: Incident HIV/ Hepatitis B Virus Infections in South African Blood Donors: Behavioral Risk... Collection: Incident HIV/Hepatitis B virus (HBV) infections in South African blood donors: Behavioral risk... (either antibody or antigen detection tests) to screen blood donors for HIV and Hepatitis-B Virus (HBV...

Psoralen/UV inactivation of HIV-1-infected cells for use in cytologic and immunologic procedures

International Nuclear Information System (INIS)

Watson, A.J.; Klaniecki, J.; Hanson, C.V.

1990-01-01

A rapid procedure for the inactivation of HIV-1-infected cells using psoralen and ultraviolet (UV) light is described. Exposure of HIV-1-infected cells to 5 micrograms/ml psoralen followed by UV irradiation (320-380 nm) for 5 minutes yields cells that are noninfectious as assessed by extended infectivity assays. The psoralen/UV inactivation procedure described is effective with cells chronically or acutely infected with HIV-1 and is unaffected by cell densities up to 12 x 10(6)/ml. At 5 micrograms/ml psoralen does little damage to cellular permeability as shown by the ability of treated cells to exclude trypan blue and propidium iodide. Psoralen/UV treatment of HIV-1-infected cells does not cause a significant decrease in the reactivity of HIV-1 core and envelope antigens or cellular antigens to monoclonal antibodies. Experiments are presented demonstrating the use of these cells for flow cytometry studies and for cell surface labeling using the lactoperoxidase 125 I iodination procedure

Risk of AIDS related complex and AIDS in homosexual men with persistent HIV antigenaemia.

OpenAIRE

de Wolf, F; Goudsmit, J; Paul, D A; Lange, J M; Hooijkaas, C; Schellekens, P; Coutinho, R A; van der Noordaa, J

1987-01-01

One hundred and ninety eight men seropositive for human immunodeficiency virus (HIV) antibody and 58 HIV antibody seroconverters were studied for an average of 19.3 (SEM 0.5) months to assess the relation between HIV antigenaemia and the risk of developing the acquired immune deficiency syndrome (AIDS) and AIDS related complex. Forty (20.2%) of the 198 HIV antibody seropositive men were antigen positive at entry and remained so during follow up. Eight (13.8%) of the 58 HIV antibody seroconver...

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...... 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...

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...... 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...

Epigenetic Metabolite Acetate Inhibits Class I/II Histone Deacetylases, Promotes Histone Acetylation, and Increases HIV-1 Integration in CD4+ T Cells.

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Bolduc, Jean-François; Hany, Laurent; Barat, Corinne; Ouellet, Michel; Tremblay, Michel J

2017-08-15

In this study, we investigated the effect of acetate, the most concentrated short-chain fatty acid (SCFA) in the gut and bloodstream, on the susceptibility of primary human CD4 + T cells to HIV-1 infection. We report that HIV-1 replication is increased in CD3/CD28-costimulated CD4 + T cells upon acetate treatment. This enhancing effect correlates with increased expression of the early activation marker CD69 and impaired class I/II histone deacetylase (HDAC) activity. In addition, acetate enhances acetylation of histones H3 and H4 and augments HIV-1 integration into the genome of CD4 + T cells. Thus, we propose that upon antigen presentation, acetate influences class I/II HDAC activity that transforms condensed chromatin into a more relaxed structure. This event leads to a higher level of viral integration and enhanced HIV-1 production. In line with previous studies showing reactivation of latent HIV-1 by SCFAs, we provide evidence that acetate can also increase the susceptibility of primary human CD4 + T cells to productive HIV-1 infection. IMPORTANCE Alterations in the fecal microbiota and intestinal epithelial damage involved in the gastrointestinal disorder associated with HIV-1 infection result in microbial translocation that leads to disease progression and virus-related comorbidities. Indeed, notably via production of short-chain fatty acids, bacteria migrating from the lumen to the intestinal mucosa could influence HIV-1 replication by epigenetic regulatory mechanisms, such as histone acetylation. We demonstrate that acetate enhances virus production in primary human CD4 + T cells. Moreover, we report that acetate impairs class I/II histone deacetylase activity and increases integration of HIV-1 DNA into the host genome. Therefore, it can be postulated that bacterial metabolites such as acetate modulate HIV-1-mediated disease progression. Copyright © 2017 American Society for Microbiology.

21 CFR 660.1 - Antibody to Hepatitis B Surface Antigen.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Antibody to Hepatitis B Surface Antigen. 660.1... Hepatitis B Surface Antigen § 660.1 Antibody to Hepatitis B Surface Antigen. (a) Proper name and definition. The proper name of this product shall be Antibody to Hepatitis B Surface Antigen. The product is...

The impact of inflammation and immune activation on B cell differentiation during HIV-1 infection

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Nicolas eRuffin

2012-01-01

Full Text Available HIV-1 infection is characterized by continuous antigenic stimulation, chronic immune activation and impaired survival of T and B cells. A decline of resting memory B cells has previously been reported to occur in both children and adults infected with HIV-1; these cells are responsible for mounting and maintaining an adequate serological response to antigens previously encountered in life through natural infection or vaccination. Further understanding of the mechanisms leading to impaired B cell differentiation and germinal center reaction might be essential to design new HIV vaccines and therapies that could improve humoral immune responses in HIV-1 infected individuals. In the present article we summarize the literature and present our view on critical mechanisms of B cell development which are impaired during HIV-1 infection. We also discuss the impact of microbial translocation, a driving force for persistent inflammation during HIV-1 infection, on survival of terminally differentiated B cells and how the altered expression of cytokines/chemokines pivotal for communication between T and B cells in lymphoid tissues may impair formation of memory B cells.

Polyfunctional analysis of Gag and Nef specific CD8+ T-cell responses in HIV-1 infected Indian individuals.

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Mendiratta, Sanjay; Vajpayee, Madhu; Mojumdar, Kamalika; Chauhan, Neeraj K; Sreenivas, Vishnubhatla

2011-02-01

Polyfunctional CD8+ T-cells have been described as most competent in controlling viral replication. We studied the impact of antigen persistence on the polyfunctional immune responses of CD8+ T-lymphocytes to HIV Gag and Nef peptides and polyclonal stimuli in 40 ART naïve HIV infected individuals and analyzed the alterations in T-cell functionality in early and late stages of infection. Significantly elevated level of global response and polyfunctional profile of CD8+ T-cells were observed to polyclonal stimulation, than HIV specific antigens in chronically infected individuals. However no key differences were observed in CD8+ T-cell functional profile in any of the 15 unique subsets for Gag and Nef specific antigens. The subjects in early stage of infection (defined as a gap of 6 months or less between seroconversion and enrolment and with no apparent clinical symptoms) had a higher degree of response functionality (4+ or 3+ different functions simultaneously) than in the late stage infection (defined as time duration since seroconversion greater than 6 months). The data suggest that persistence of antigen during chronic infection leads to functional impairment of HIV specific responses. Copyright © 2010 Elsevier Ltd. All rights reserved.

HIV-1-infected monocyte-derived dendritic cells do not undergo maturation but can elicit IL-10 production and T cell regulation

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Granelli-Piperno, Angela; Golebiowska, Angelika; Trumpfheller, Christine; Siegal, Frederick P.; Steinman, Ralph M.

2004-05-01

Dendritic cells (DCs) undergo maturation during virus infection and thereby become potent stimulators of cell-mediated immunity. HIV-1 replicates in immature DCs, but we now find that infection is not accompanied by many components of maturation in either infected cells or uninfected bystanders. The infected cultures do not develop potent stimulating activity for the mixed leukocyte reaction (MLR), and the DCs producing HIV-1 gag p24 do not express CD83 and DC-lysosome-associated membrane protein maturation markers. If different maturation stimuli are applied to DCs infected with HIV-1, the infected cells selectively fail to mature. When DCs from HIV-1-infected patients are infected and cultured with autologous T cells, IL-10 was produced in 6 of 10 patients. These DC-T cell cocultures could suppress another immune response, the MLR. The regulation was partially IL-10-dependent and correlated in extent with the level of IL-10 produced. Suppressor cells only developed from infected patients, rather than healthy controls, and the DCs had to be exposed to live virus rather than HIV-1 gag peptides or protein. These results indicate that HIV-1-infected DCs have two previously unrecognized means to evade immune responses: maturation can be blocked reducing the efficacy of antigen presentation from infected cells, and T cell-dependent suppression can be induced.

Designing Peptide-Based HIV Vaccine for Chinese

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Fan, Xiaojuan

2014-01-01

CD4+ T cells are central to the induction and maintenance of CD8+ T cell and antibody-producing B cell responses, and the latter are essential for the protection against disease in subjects with HIV infection. How to elicit HIV-specific CD4+ T cell responses in a given population using vaccines is one of the major areas of current HIV vaccine research. To design vaccine that targets specifically Chinese, we assembled a database that is comprised of sequences from 821 Chinese HIV isolates and 46 human leukocyte antigen (HLA) DR alleles identified in Chinese population. We then predicted 20 potential HIV epitopes using bioinformatics approaches. The combination of these 20 epitopes has a theoretical coverage of 98.1% of the population for both the prevalent HIV genotypes and also Chinese HLA-DR types. We suggest that testing this vaccine experimentally will facilitate the development of a CD4+ T cell vaccine especially catered for Chinese. PMID:25136573

HIV enteropathy and aging: gastrointestinal immunity, mucosal epithelial barrier, and microbial translocation.

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Wang, Hongyin; Kotler, Donald P

2014-07-01

Despite decreases in morbidity and mortality as a result of antiretroviral therapy, gastrointestinal dysfunction remains common in HIV infection. Treated patients are at risk for complications of 'premature' aging, such as cardiovascular disease, osteopenia, neurocognitive decline, malignancies, and frailty. This review summarizes recent observations in this field. Mucosal CD4 lymphocytes, especially Th17 cells, are depleted in acute HIV and simian immune deficiency virus (SIV) infections, although other cell types also are affected. Reconstitution during therapy often is incomplete, especially in mucosa. Mucosal barrier function is affected by both HIV infection and aging and includes paracellular transport via tight junctions and uptake through areas of apoptosis; other factors may affect systemic antigen exposure. The resultant microbial translocation is associated with systemic immune activation in HIV and SIV infections. There is evidence of immune activation and microbial translocation in the elderly. The immune phenotypes of immunosenescence in HIV infection and aging appear similar. There are several targets for intervention; blockage of residual mucosal virus replication, preventing antigen uptake, modulating the microbiome, improving T cell recovery, combining therapies aimed at mucosal integrity, augmenting mucosal immunity, and managing traditional risk factors for premature aging in the general population. Aging may interact with HIV enteropathy to enhance microbial translocation and immune activation.

The effect of treatment with zidovudine with or without acyclovir on HIV p24 antigenaemia in patients with AIDS or AIDS-related complex

DEFF Research Database (Denmark)

Pedersen, C; Cooper, D A; Brun-Vézinet, F

1992-01-01

with AIDS, AIDS-related complex (ARC) or Kaposi's sarcoma (KS). DESIGN: Double-blind, placebo-controlled randomized clinical trial of less than or equal to 6 months' therapy. SETTING: Samples were obtained from patients attending teaching hospital outpatient clinics in seven European countries and Australia....... SUBJECTS: One hundred and ninety-seven HIV-infected patients (60 with AIDS and 137 with ARC or KS). MAIN OUTCOME MEASURES: Serum HIV p24-antigen levels measured using the Abbott HIV solid-phase enzyme immunoassay. RESULTS: Of 76 ARC/KS patients who were initially HIV p24-antigen-positive, one out of 25...

Rapid High-Level Production of Functional HIV Broadly Neutralizing Monoclonal Antibodies in Transient Plant Expression Systems

Science.gov (United States)

Rosenberg, Yvonne; Sack, Markus; Montefiori, David; Forthal, Donald; Mao, Lingjun; -Abanto, Segundo Hernandez; Urban, Lori; Landucci, Gary; Fischer, Rainer; Jiang, Xiaoming

2013-01-01

Passive immunotherapy using anti-HIV broadly neutralizing monoclonal antibodies (mAbs) has shown promise as an HIV treatment, reducing mother-to-child-transmission (MTCT) of simian/human immunodeficiency virus (SHIV) in non-human primates and decreasing viral rebound in patients who ceased receiving anti-viral drugs. In addition, a cocktail of potent mAbs may be useful as mucosal microbicides and provide an effective therapy for post-exposure prophylaxis. However, even highly neutralizing HIV mAbs used today may lose their effectiveness if resistance occurs, requiring the rapid production of new or engineered mAbs on an ongoing basis in order to counteract the viral resistance or the spread of a certain HIV-1 clade in a particular region or patient. Plant-based expression systems are fast, inexpensive and scalable and are becoming increasingly popular for the production of proteins and monoclonal antibodies. In the present study, Agrobacterium-mediated transient transfection of plants, utilizing two species of Nicotiana, have been tested to rapidly produce high levels of an HIV 89.6PΔ140env and several well-studied anti-HIV neutralizing monoclonal antibodies (b12, 2G12, 2F5, 4E10, m43, VRC01) or a single chain antibody construct (m9), for evaluation in cell-based viral inhibition assays. The protein-A purified plant-derived antibodies were intact, efficiently bound HIV envelope, and were equivalent to, or in one case better than, their counterparts produced in mammalian CHO or HEK-293 cells in both neutralization and antibody dependent viral inhibition assays. These data indicate that transient plant-based transient expression systems are very adaptable and could rapidly generate high levels of newly identified functional recombinant HIV neutralizing antibodies when required. In addition, they warrant detailed cost-benefit analysis of prolonged incubation in plants to further increase mAb production. PMID:23533588

Rapid high-level production of functional HIV broadly neutralizing monoclonal antibodies in transient plant expression systems.

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Yvonne Rosenberg

Full Text Available Passive immunotherapy using anti-HIV broadly neutralizing monoclonal antibodies (mAbs has shown promise as an HIV treatment, reducing mother-to-child-transmission (MTCT of simian/human immunodeficiency virus (SHIV in non-human primates and decreasing viral rebound in patients who ceased receiving anti-viral drugs. In addition, a cocktail of potent mAbs may be useful as mucosal microbicides and provide an effective therapy for post-exposure prophylaxis. However, even highly neutralizing HIV mAbs used today may lose their effectiveness if resistance occurs, requiring the rapid production of new or engineered mAbs on an ongoing basis in order to counteract the viral resistance or the spread of a certain HIV-1 clade in a particular region or patient. Plant-based expression systems are fast, inexpensive and scalable and are becoming increasingly popular for the production of proteins and monoclonal antibodies. In the present study, Agrobacterium-mediated transient transfection of plants, utilizing two species of Nicotiana, have been tested to rapidly produce high levels of an HIV 89.6PΔ140env and several well-studied anti-HIV neutralizing monoclonal antibodies (b12, 2G12, 2F5, 4E10, m43, VRC01 or a single chain antibody construct (m9, for evaluation in cell-based viral inhibition assays. The protein-A purified plant-derived antibodies were intact, efficiently bound HIV envelope, and were equivalent to, or in one case better than, their counterparts produced in mammalian CHO or HEK-293 cells in both neutralization and antibody dependent viral inhibition assays. These data indicate that transient plant-based transient expression systems are very adaptable and could rapidly generate high levels of newly identified functional recombinant HIV neutralizing antibodies when required. In addition, they warrant detailed cost-benefit analysis of prolonged incubation in plants to further increase mAb production.

DNA/MVA Vaccines for HIV/AIDS

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Smita S. Iyer

2014-02-01

Full Text Available Since the initial proof-of-concept studies examining the ability of antigen-encoded plasmid DNA to serve as an immunogen, DNA vaccines have evolved as a clinically safe and effective platform for priming HIV-specific cellular and humoral responses in heterologous “prime-boost” vaccination regimens. Direct injection of plasmid DNA into the muscle induces T- and B-cell responses against foreign antigens. However, the insufficient magnitude of this response has led to the development of approaches for enhancing the immunogenicity of DNA vaccines. The last two decades have seen significant progress in the DNA-based vaccine platform with optimized plasmid constructs, improved delivery methods, such as electroporation, the use of molecular adjuvants and novel strategies combining DNA with viral vectors and subunit proteins. These innovations are paving the way for the clinical application of DNA-based HIV vaccines. Here, we review preclinical studies on the DNA-prime/modified vaccinia Ankara (MVA-boost vaccine modality for HIV. There is a great deal of interest in enhancing the immunogenicity of DNA by engineering DNA vaccines to co-express immune modulatory adjuvants. Some of these adjuvants have demonstrated encouraging results in preclinical and clinical studies, and these data will be examined, as well.

HIV: current opinion in escapology.

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Klenerman, Paul; Wu, Ying; Phillips, Rodney

2002-08-01

Much recent work strongly supports the hypothesis that CD8(+) T lymphocytes (CTLs) exert important immune control over HIV and so are a major selective force in its evolution. We analyse this host-pathogen interplay and focus on new data that describe the overall 'effectiveness' of CTL responses (strength, spread, specificity and 'stamina') and the mechanisms by which HIV may evade this suppressive activity. CTLs directed against HIV recognise very large numbers of distinct epitopes across the genome, are largely functional, turn over rapidly, and possess a phenotype that is distinct from CD8(+) lymphocytes specific for other viruses. Mutation of HIV epitopes that alters or abolishes CTL recognition altogether appears to be the most important immune escape mechanism, as the variation that HIV generates defies the limits of the T cell repertoire. However, this immune evasion is still only well-studied in a few patients. The rules that govern immune escape, and the ultimate limits of CTL capacity to deal with the variant epitopes that currently circulate, are not understood. This information will determine the feasibility of current vaccine approaches that, so far, make no provision for the enormous antigenic plasticity of HIV.

HIV-1 specific IgA detected in vaginal secretions of HIV uninfected women participating in a microbicide trial in Southern Africa are primarily directed toward gp120 and gp140 specificities.

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Kelly E Seaton

Full Text Available Many participants in microbicide trials remain uninfected despite ongoing exposure to HIV-1. Determining the emergence and nature of mucosal HIV-specific immune responses in such women is important, since these responses may contribute to protection and could provide insight for the rational design of HIV-1 vaccines.We first conducted a pilot study to compare three sampling devices (Dacron swabs, flocked nylon swabs and Merocel sponges for detection of HIV-1-specific IgG and IgA antibodies in vaginal secretions. IgG antibodies from HIV-1-positive women reacted broadly across the full panel of eight HIV-1 envelope (Env antigens tested, whereas IgA antibodies only reacted to the gp41 subunit. No Env-reactive antibodies were detected in the HIV-negative women. The three sampling devices yielded equal HIV-1-specific antibody titers, as well as total IgG and IgA concentrations. We then tested vaginal Dacron swabs archived from 57 HIV seronegative women who participated in a microbicide efficacy trial in Southern Africa (HPTN 035. We detected vaginal IgA antibodies directed at HIV-1 Env gp120/gp140 in six of these women, and at gp41 in another three women, but did not detect Env-specific IgG antibodies in any women.Vaginal secretions of HIV-1 infected women contained IgG reactivity to a broad range of Env antigens and IgA reactivity to gp41. In contrast, Env-binding antibodies in the vaginal secretions of HIV-1 uninfected women participating in the microbicide trial were restricted to the IgA subtype and were mostly directed at HIV-1 gp120/gp140.

Expression and Antigenic Evaluation of VacA Antigenic Fragment of Helicobacter Pylori

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Hasanzadeh, Leila; Ghaznavi-Rad, Ehsanollah; Soufian, Safieh; Farjadi, Vahideh; Abtahi, Hamid

2013-01-01

Objective(s) : Helicobacter pylori, a human specific gastric pathogen is a causative agent of chronic active gastritis. The vacuolating cytotoxin (VacA) is an effective virulence factor involved in gastric injury. The aim of this study was to construct a recombinant protein containing antigenic region of VacA gene and determine its antigenicity. Materials and Methods: The antigenic region of VacA gene was detected by bioinformatics methods. The polymerase chain reaction method was used to amplify a highly antigenic region of VacA gene from chromosomal DNA of H. pylori. The eluted product was cloned into the prokaryotic expression vector pET32a. The target protein was expressed in the Escherichia coli BL21 (DE3) pLysS. The bacteria including pET32a-VacA plasmids were induced by IPTG. The antigenicity was finally studied by western blotting using sera of 15 H. pylori infected patients after purification. Results: Enzyme digestion analysis, PCR and DNA sequencing results showed that the target gene was inserted correctly into the recombinant vector. The expressed protein was purified successfully via affinity chromatography. Data indicated that antigenic region of VacA protein from Helicobacter pylori was recognized by all 15 patient’s sera. Conclusion : Our data showed that antigenic region of VacA protein can be expressed by in E. co.li. This protein was recognized by sera patients suffering from H. pylori infection. the recombinant protein has similar epitopes and close antigenic properties to the natural form of this antigen. Recombinant antigenic region of VacA protein also seems to be a promising antigen for protective and serologic diagnosis . PMID:23997913

Expression and Antigenic Evaluation of VacA Antigenic Fragment of Helicobacter Pylori

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Leila Hasanzadeh

2013-07-01

Full Text Available Objective(s: Helicobacter pylori, a human specific gastric pathogen is a causative agent of chronic active gastritis. The vacuolating cytotoxin (VacA is an effective virulence factor involved in gastric injury. The aim of this study was to construct a recombinant protein containing antigenic region of VacA gene and determine its antigenicity.   Materials and Methods: The antigenic region of VacA gene was detected by bioinformatics methods. The polymerase chain reaction method was used to amplify a highly antigenic region of VacA gene from chromosomal DNA of H. pylori. The eluted product was cloned into the prokaryotic expression vector pET32a. The target protein was expressed in the Escherichia coli BL21 (DE3 pLysS. The bacteria including pET32a-VacA plasmids were induced by IPTG. The antigenicity was finally studied by western blotting using sera of 15 H. pylori infected patients after purification. Results: Enzyme digestion analysis, PCR and DNA sequencing results showed that the target gene was inserted correctly into the recombinant vector. The expressed protein was purified successfully via affinity chromatography. Data indicated that antigenic region of VacA protein from Helicobacter pylori was recognized by all 15 patient’s sera. Conclusion : Our data showed that antigenic region of VacA protein can be expressed by in E. co.li. This protein was recognized by sera patients suffering from H. pylori infection. the recombinant protein has similar epitopes and close antigenic properties to the natural form of this antigen. Recombinant antigenic region of VacA protein also seems to be a promising antigen for protective and serologic diagnosis .

HIV infection and aging: enhanced Interferon- and Tumor Necrosis Factor-alpha production by the CD8+ CD28- T subset

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Colón-Martinez Sol

2001-10-01

Full Text Available Abstract Background T cells from HIV+ and aged individuals show parallels in terms of suppressed proliferative activity and interleukin-2 (I1-2 production and an increased number of CD8+ CD28- T cells. In order to compare cytokine production from T cells from these two states, CD4+ and CD8+ T cells from HIV+ aged, and normal young donors (controls were monitored for cytokine production by flow cytometry, quantitative PCR and ELISA upon activation by PMA and anti-CD3. In addition, the CD8+ T cell subsets CD28+ and CD28- from the HIV+ and the aged groups were evaluated for cytokine production by flow cytometry, and compared with those from young controls. Results Flow cytometric analysis indicated that CD8+ T cells from both HIV+ and aged donors showed an increase of approximately 2–3 fold over controls in percentage of cells producing inflammatory cytokines IFN-γ and TNF-α. Similar analysis also revealed that the production of interleukins-4,6 and 10, production was very low (1–2% of cells and unchanged in these cells. Quantitative PCR also showed a substantial increase (4–5 fold in IFN-γ and TNF-α mRNA from HIV+ and aged CD8+ T cells, as did ELISA for secreted IFN-γ and TNF-α (2.3–4 fold. Flow cytometric analysis showed that the CD8+ CD28- T cell subset accounts for approximately 80–86% of the IFN-γ and TNF-α production from the CD8+ subset in the aged and HIV+ states. The CD4+ T cell, while not significantly changed in the HIV+ or aged states in terms of IFN-γ production, showed a small but significant increase in TNF-α production in both states. Conclusions Our data appear compatible with physiologic conditions existing in HIV+ and aged individuals, i.e. elevated serum levels and elevated CD8+ T cell production of IFN-γ and TNF-α. Thus, the capacity for increased production of cytokines IFN-γ and TNF-α in the aged individual by the dominant CD8+ CD28- subset may have a profound influence on the clinical state by

Proteasome-independent degradation of HIV-1 in naturally non-permissive human placental trophoblast cells

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Barré-Sinoussi Françoise

2009-05-01

Full Text Available Abstract Background The human placenta-derived cell line BeWo has been demonstrated to be restrictive to cell-free HIV-1 infection. BeWo cells are however permissive to infection by VSV-G pseudotyped HIV-1, which enters cells by a receptor-independent mechanism, and to infection by HIV-1 via a cell-to-cell route. Results Here we analysed viral entry in wild type BeWo (CCR5+, CXCR4+ and BeWo-CD4+ (CD4+, CCR5+, CXCR4+ cells. We report that HIV-1 internalisation is not restricted in either cell line. Levels of internalised p24 antigen between VSV-G HIV-1 pseudotypes and R5 or X4 virions were comparable. We next analysed the fate of internalised virions; X4 and R5 HIV-1 virions were less stable over time in BeWo cells than VSV-G HIV-1 pseudotypes. We then investigated the role of the proteasome in restricting cell-free HIV-1 infection in BeWo cells using proteasome inhibitors. We observed an increase in the levels of VSV-G pseudotyped HIV-1 infection in proteasome-inhibitor treated cells, but the infection by R5-Env or X4-Env pseudotyped virions remains restricted. Conclusion Collectively these results suggest that cell-free HIV-1 infection encounters a surface block leading to a non-productive entry route, which either actively targets incoming virions for non-proteasomal degradation, and impedes their release into the cytoplasm, or causes the inactivation of mechanisms essential for viral replication.

Growth, productivity, and scientific impact of sources of HIV/AIDS ...

African Journals Online (AJOL)

This study uses an informetric approach to examine the growth, productivity and scientific impact of these sources, during the period 1980 to 2005, and especially to measure performance in the publication and dissemination of HIV/AIDS research about or from eastern or southern Africa. Data were collected from MEDLINE, ...

Triterpenoids from Ocimum labiatum Activates Latent HIV-1 Expression In Vitro: Potential for Use in Adjuvant Therapy

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Petrina Kapewangolo

2017-10-01

Full Text Available Latent HIV reservoirs in infected individuals prevent current treatment from eradicating infection. Treatment strategies against latency involve adjuvants for viral reactivation which exposes viral particles to antiretroviral drugs. In this study, the effect of novel triterpenoids isolated from Ocimum labiatum on HIV-1 expression was measured through HIV-1 p24 antigen capture in the U1 latency model of HIV-1 infection and in peripheral blood mononuclear cells (PBMCs of infected patients on combination antiretroviral therapy (cART. The mechanism of viral reactivation was determined through the compound’s effect on cytokine production, histone deacetylase (HDAC inhibition, and protein kinase C (PKC activation. Cytotoxicity of the triterpenoids was determined using a tetrazolium dye and flow cytometry. The isolated triterpene isomers, 3-hydroxy-4,6a,6b,11,12,14b-hexamethyl-1,2,3,4,6,6a,6b,7,8,8a,9,10,11,12,12a,14,14a,14b-octadecahydropicene-4,8a-dicarboxylic acid (HHODC, significantly (p < 0.05 induced HIV-1 expression in a dose-dependent manner in U1 cells at non-cytotoxic concentrations. HHODC also induced viral expression in PBMCs of HIV-1 infected patients on cART. In addition, the compound up-regulated the production of interleukin (IL-2, IL-6, tumour necrosis factor (TNF-α, and interferon (IFN-γ but had no effect on HDAC and PKC activity, suggesting cytokine upregulation as being involved in latency activation. The observed in vitro reactivation of HIV-1 introduces the adjuvant potential of HHODC for the first time here.

[Epidemiological study on HIV/AIDS in Cambodia seroprevalence of HIV/STD among commercial sex workers].

Science.gov (United States)

Ohshige, K; Morio, S; Mizushima, S; Kitamura, K; Tajima, K; Ito, A; Suyama, A; Usuku, S; Phalla, T; Leng, H B; Sopheab, H; Eab, B; Soda, K

1999-01-01

To describe epidemiological features of HIV prevalence among female commercial sex workers (CSWs) in Cambodia, a cross-sectional study using a questionnaire study and serological tests was carried out from December 1997 to January 1998. We report the main results of the analyses of serological tests in this article. Two hundred ninety six CSWs working in Sisophon and Poi Pet, located in northwest Cambodia, Bantey Mean Chey province, were recruited for interview based on a questionnaire on sexual behavior, and serological tests. The blood samples were examined for HIV antibody, Chlamydia trachomatis IgG antibody, TPHA, Hepatitis B surface antigen, and Hepatitis B surface antibody. The relationship between HIV and the other STD's was analyzed by using logistic regression analysis. The HIV seroprevalence rate was 43.9% (130 out of 296). The seropositive rate of Chlamydia trachomatis IgG antibody (C.T.-IgG-Ab) was 73.3% (217 out of 296). Logistic regression analysis showed a significant association between C.T.-IgG-Ab positive and HIV prevalence. (Odds Ratio: 5.33; 95% Confidence Interval, 2.82-10.07). This study suggests that the existence of Chlamydia trachomatis is closely related with HIV prevalence among CSWs in Cambodia. Other STDs may also increase susceptibility to male-to-female sexual transmission of HIV. This suggests that appropriate prevention against STDs will be needed for the control of HIV prevalence in Cambodia.

Interferon-¿ and interleukin-4 production by human T cells recognizing Leishmania donovani antigens separated by SDS-PAGE

DEFF Research Database (Denmark)

Bahrenscheer, J; Kemp, M; Kurtzhals, J A

1995-01-01

of proliferation and interferon-gamma (IFN-gamma) production in cultures of peripheral blood mononuclear cells (PBMC) from individuals who had recovered from visceral leishmaniasis caused by L. donovani. The release of interleukin-4 (IL-4) by PBMC stimulated with the isolated L. donovani antigen fractions...... was measured after treatment with phorbol-myristate-acetate and ionomycin. The cells proliferated in response to all protein fractions with molecular weights in the range production...... was infrequently observed. The results show that T cells from individuals who have been cured of visceral leishmaniasis recognize and respond to a wide range of leishmanial antigens. There was no evidence of particular fractions constantly giving either IFN-gamma or IL-4-producing responses....

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

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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.

Optimizing Production of Antigens and Fabs in the Context of Generating Recombinant Antibodies to Human Proteins.

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Nan Zhong

Full Text Available We developed and optimized a high-throughput project workflow to generate renewable recombinant antibodies to human proteins involved in epigenetic signalling. Three different strategies to produce phage display compatible protein antigens in bacterial systems were compared, and we found that in vivo biotinylation through the use of an Avi tag was the most productive method. Phage display selections were performed on 265 in vivo biotinylated antigen domains. High-affinity Fabs (<20nM were obtained for 196. We constructed and optimized a new expression vector to produce in vivo biotinylated Fabs in E. coli. This increased average yields up to 10-fold, with an average yield of 4 mg/L. For 118 antigens, we identified Fabs that could immunoprecipitate their full-length endogenous targets from mammalian cell lysates. One Fab for each antigen was converted to a recombinant IgG and produced in mammalian cells, with an average yield of 15 mg/L. In summary, we have optimized each step of the pipeline to produce recombinant antibodies, significantly increasing both efficiency and yield, and also showed that these Fabs and IgGs can be generally useful for chromatin immunoprecipitation (ChIP protocols.

Proteomic analysis of the excretory/secretory products and antigenic proteins of Echinococcus granulosus adult worms from infected dogs.

Science.gov (United States)

Wang, Ying; Xiao, Di; Shen, Yujuan; Han, Xiuming; Zhao, Fei; Li, Xiaohong; Wu, Weiping; Zhou, Hejun; Zhang, Jianzhong; Cao, Jianping

2015-05-21

Cystic echinococcosis, which is caused by Echinococcus granulosus, is one of the most widespread zoonotic helminth diseases that affects humans and livestock. Dogs, which harbor adult worms in their small intestines, are a pivotal source of E. granulosus infection in humans and domestic animals. Therefore, novel molecular approaches for the prevention and diagnosis of this parasite infection in dogs need to be developed. In this study, we performed proteomic analysis to identify excretory/secretory products (ES) and antigenic proteins of E. granulosus adult worms using two-dimensional electrophoresis, tandem matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF/TOF), and Western blotting of sera from infected dogs. This study identified 33 ES product spots corresponding to 9 different proteins and 21 antigenic protein spots corresponding to 13 different proteins. Six antigenic proteins were identified for the first time. The present study extended the existing proteomic data of E. granulosus and provides further information regarding host-parasite interactions and survival mechanisms. The results of this study contribute to vaccination and immunodiagnoses for E. granulosus infections.

HIV impairs opsonic phagocytic clearance of pregnancy-associated malaria parasites.

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Jessica Keen

2007-05-01

Full Text Available BACKGROUND: Primigravid (PG women are at risk for pregnancy-associated malaria (PAM. Multigravid (MG women acquire protection against PAM; however, HIV infection impairs this protective response. Protection against PAM is associated with the production of IgG specific for variant surface antigens (VSA-PAM expressed by chondroitin sulfate A (CSA-adhering parasitized erythrocytes (PEs. We hypothesized that VSA-PAM-specific IgG confers protection by promoting opsonic phagocytosis of PAM isolates and that HIV infection impairs this response. METHODS AND FINDINGS: We assessed the ability of VSA-PAM-specific IgG to promote opsonic phagocytosis of CSA-adhering PEs and the impact of HIV infection on this process. Opsonic phagocytosis assays were performed using the CSA-adherent parasite line CS2 and human and murine macrophages. CS2 PEs were opsonized with plasma or purified IgG subclasses from HIV-negative or HIV-infected PG and MG Kenyan women or sympatric men. Levels of IgG subclasses specific for VSA-PAM were compared in HIV-negative and HIV-infected women by flow cytometry. Plasma from HIV-negative MG women, but not PG women or men, promoted the opsonic phagocytosis of CSA-binding PEs (p < 0.001. This function depended on VSA-PAM-specific plasma IgG1 and IgG3. HIV-infected MG women had significantly lower plasma opsonizing activity (median phagocytic index 46 [interquartile range (IQR 18-195] versus 251 [IQR 93-397], p = 0.006 and levels of VSA-PAM-specific IgG1 (mean fluorescence intensity [MFI] 13 [IQR 11-20] versus 30 [IQR 23-41], p < 0.001 and IgG3 (MFI 17 [IQR 14-23] versus 28 [IQR 23-37], p < 0.001 than their HIV-negative MG counterparts. CONCLUSIONS: Opsonic phagocytosis may represent a novel correlate of protection against PAM. HIV infection may increase the susceptibility of multigravid women to PAM by impairing this clearance mechanism.

Bordetella bronchiseptica antigen enhances the production of Mycoplasma hyopneumoniae antigen-specific immunoglobulin G in mice.

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Yim, Seol-Hwa; Hahn, Tae-Wook; Joo, Hong-Gu

2017-09-30

We previously demonstrated that Bordetella ( B .) bronchiseptica antigen (Ag) showed high immunostimulatory effects on mouse bone marrow cells (BMs) while Mycoplasma ( M .) hyopneumoniae Ag showed low effects. The focus of this study was to determine if B. bronchiseptica Ag can enhance the M. hyopneumoniae Ag-specific immune response and whether the host's immune system can recognize both Ags. MTT assay results revealed that each or both Ags did not significantly change BM metabolic activity. Flow cytometry analysis using carboxyfluorescein succinimidyl ester showed that B. bronchiseptica Ag can promote the division of BMs. In cytokine and nitric oxide (NO) assays, B. bronchiseptica Ag boosted production of tumor necrosis factor-alpha in M. hyopneumoniae Ag-treated BMs, and combined treatment with both Ags elevated the level of NO in BMs compared to that from treatment of M. hyopneumoniae Ag alone. Immunoglobulin (Ig)G enzyme-linked immunosorbent assay using the sera of Ag-injected mice clearly indicated that B. bronchiseptica Ag can increase the production of M. hyopneumoniae Ag-specific IgG. This study provided information valuable in the development of M. hyopneumoniae vaccines and showed that B. bronchiseptica Ag can be used both as a vaccine adjuvant and as a vaccine Ag.

HIV-particles in spermatozoa of patients with AIDS and their transfer into the oocyte

Science.gov (United States)

Baccetti, B; Benedetto, A; Burrini, AG; Collodel, G; Ceccarini, EC; Crisa, N; Di Caro, A; Estenoz, M; Garbuglia, AR; Massacesi, A; Piomboni, P; Renieri, T; Solazzo, D

1994-01-01

By immunocytochemistry and in situ hybridization at the electron microscopy level, and by the PCR technique, we have shown that HIV-1 binds and enters normal sperm; that viral particles, their antigens, and nucleic acid are present in sperm from HIV-1 infected men; and that such sperm can transfer HIV-1 like particles to normal human oocytes. We also present evidence that a galactosylceramide-like compound is present on the sperm membrane and could function as an alternative receptor for HIV. PMID:7962075

Safety and immunogenicity of a live recombinant canarypox virus expressing HIV type 1 gp120 MN MN tm/gag/protease LAI (ALVAC-HIV, vCP205) followed by a p24E-V3 MN synthetic peptide (CLTB-36) administered in healthy volunteers at low risk for HIV infection. AGIS Group and L'Agence Nationale de Recherches sur Le Sida.

Science.gov (United States)

Salmon-Céron, D; Excler, J L; Finkielsztejn, L; Autran, B; Gluckman, J C; Sicard, D; Matthews, T J; Meignier, B; Valentin, C; El Habib, R; Blondeau, C; Raux, M; Moog, C; Tartaglia, J; Chong, P; Klein, M; Milcamps, B; Heshmati, F; Plotkin, S

1999-05-01

A live recombinant canarypox vector expressing HIV-1 gpl20 MN tm/gag/protease LAI (ALVAC-HIV, vCP205) alone or boosted by a p24E-V3 MN synthetic peptide (CLTB-36) was tested in healthy volunteers at low risk for HIV infection for their safety and immunogenicity. Both antigens were well tolerated. ALVAC-HIV (vCP205) induced low levels of neutralizing antibodies against HIV-1 MN in 33% of the volunteers. None of them had detectable neutralizing antibodies against a nonsyncytium-inducing HIV-1 clade B primary isolate (Bx08). After the fourth injection of vCP205, CTL activity was detected in 33% of the volunteers and was directed against Env, Gag, and Pol. This activity was mediated by both CD4+ and CD8+ lymphocytes. On the other hand, the CLTB-36 peptide was poorly immunogenic and induced no neutralizing antibodies or CTLs. Although the ALVAC-HIV (vCP205) and CLTB-36 prime-boost regimen was not optimal, further studies with ALVAC-HIV (vCP205) are warranted because of its clear induction of a cellular immune response and utility as a priming agent for other subunit antigens such as envelope glycoproteins, pseudoparticles, or new peptides.

HCV Specific IL-21 Producing T Cells but Not IL-17A Producing T Cells Are Associated with HCV Viral Control in HIV/HCV Coinfection.

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Sonya A MacParland

Full Text Available Decreased hepatitis C virus (HCV clearance, faster cirrhosis progression and higher HCV RNA levels are associated with Human Immunodeficiency virus (HIV coinfection. The CD4+ T helper cytokines interleukin (IL-21 and IL-17A are associated with virus control and inflammation, respectively, both important in HCV and HIV disease progression. Here, we examined how antigen-specific production of these cytokines during HCV mono and HIV/HCV coinfection was associated with HCV virus control.We measured HCV-specific IL-21 and IL-17A production by transwell cytokine secretion assay in PBMCs from monoinfected and coinfected individuals. Viral control was determined by plasma HCV RNA levels.In acutely infected individuals, those able to establish transient/complete HCV viral control tended to have stronger HCV-specific IL-21-production than non-controllers. HCV-specific IL-21 production also correlated with HCV viral decline in acute infection. Significantly stronger HCV-specific IL-21 production was detected in HAART-treated coinfected individuals. HCV-specific IL-17A production was not associated with lower plasma HCV RNA levels in acute or chronic HCV infection and responses were stronger in HIV coinfection. HCV-specific IL-21/ IL-17A responses did not correlate with microbial translocation or fibrosis. Exogenous IL-21 treatment of HCV-specific CD8+ T cells from monoinfected individuals enhanced their function although CD8+ T cells from coinfected individuals were somewhat refractory to the effects of IL-21.These data show that HCV-specific IL-21 and IL-17A-producing T cells are induced in HIV/HCV coinfection. In early HIV/HCV coinfection, IL-21 may contribute to viral control, and may represent a novel tool to enhance acute HCV clearance in HIV/HCV coinfected individuals.

Role of T. cruzi exposure in the pattern of T cell cytokines among chronically infected HIV and Chagas disease patients

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Tania Regina Tozetto-Mendoza

Full Text Available OBJECTIVES: The impact of Chagas disease (CD in HIV-infected patients is relevant throughout the world. In fact, the characterization of the adaptive immune response in the context of co-infection is important for predicting the need for interventions in areas in which HIV and Chagas disease co-exist. METHODS: We described and compared the frequency of cytokine-producing T cells stimulated with soluble antigen of Trypanosoma cruzi (T. cruzi using a cytometric assay for the following groups: individuals with chronic Chagas disease (CHR, n=10, those with Chagas disease and HIV infection (CO, n=11, those with only HIV (HIV, n=14 and healthy individuals (C, n=15. RESULTS: We found 1 a constitutively lower frequency of IL-2+ and IFN-γ+ T cells in the CHR group compared with the HIV, CO and healthy groups; 2 a suppressive activity of soluble T. cruzi antigen, which down-regulated IL-2+CD4+ and IFN-γ+CD4+ phenotypes, notably in the healthy group; 3 a down-regulation of inflammatory cytokines on CD8+ T cells in the indeterminate form of Chagas disease; and 4 a significant increase in IL-10+CD8+ cells distinguishing the indeterminate form from the cardiac/digestive form of Chagas disease, even in the presence of HIV infection. CONCLUSIONS: Taken together, our data suggest the presence of an immunoregulatory response in chronic Chagas disease, which seems to be driven by T. cruzi antigens. Our findings provide new insights into immunotherapeutic strategies for people living with HIV/AIDS and Chagas disease.

HIV/SIV infection primes monocytes and dendritic cells for apoptosis.

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Mireille Laforge

2011-06-01

Full Text Available Subversion or exacerbation of antigen-presenting cells (APC death modulates host/pathogen equilibrium. We demonstrated during in vitro differentiation of monocyte-derived macrophages and monocyte-derived dendritic cells (DCs that HIV sensitizes the cells to undergo apoptosis in response to TRAIL and FasL, respectively. In addition, we found that HIV-1 increased the levels of pro-apoptotic Bax and Bak molecules and decreased the levels of anti-apoptotic Mcl-1 and FLIP proteins. To assess the relevance of these observations in the context of an experimental model of HIV infection, we investigated the death of APC during pathogenic SIV-infection in rhesus macaques (RMs. We demonstrated increased apoptosis, during the acute phase, of both peripheral blood DCs and monocytes (CD14(+ from SIV(+RMs, associated with a dysregulation in the balance of pro- and anti-apoptotic molecules. Caspase-inhibitor and death receptors antagonists prevented apoptosis of APCs from SIV(+RMs. Furthermore, increased levels of FasL in the sera of pathogenic SIV(+RMs were detected, compared to non-pathogenic SIV infection of African green monkey. We suggest that inappropriate apoptosis of antigen-presenting cells may contribute to dysregulation of cellular immunity early in the process of HIV/SIV infection.

Testing for HIV

Science.gov (United States)

... Medical Devices Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products Vaccines, Blood & Biologics Home Vaccines, Blood & Biologics Safety & Availability (Biologics) HIV Home Test Kits Testing for HIV Share Tweet Linkedin Pin it More ...

Tubuloreticular inclusions in skin biopsies from patients with HIV infection

DEFF Research Database (Denmark)

Pedersen, C; Horn, T; Junge, Jette

1989-01-01

Skin biopsies obtained from apparently normal skin from 15 HIV infected patients and 6 anti-HIV negative patients were examined by electron microscopy. Tubuloreticular inclusions (TRI) were detected within the cytoplasm of capillary endothelial cells in 5/5 AIDS patients and in 2/5 patients...... of the patients without TRI, interferon activity was below detection level. The occurrence of TRI was not dependent on the presence of free p24 antigen in serum. It is concluded that the occurrence of TRI in entothelial cells of skin capillaries is associated with late stages of HIV infection and this may...

Prediction of exposed domains of envelope glycoprotein in Indian HIV-1 isolates and experimental confirmation of their immunogenicity in humans

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Mohabatkar H.

2004-01-01

Full Text Available We describe the impact of subtype differences on the seroreactivity of linear antigenic epitopes in envelope glycoprotein of HIV-1 isolates from different geographical locations. By computer analysis, we predicted potential antigenic sites of envelope glycoprotein (gp120 and gp4l of this virus. For this purpose, after fetching sequences of proteins of interest from data banks, values of hydrophilicity, flexibility, accessibility, inverted hydrophobicity, and secondary structure were considered. We identified several potential antigenic epitopes in a B subtype strain of envelope glycoprotein of HIV-1 (IIIB. Solid- phase peptide synthesis methods of Merrifield and Fmoc chemistry were used for synthesizing peptides. These synthetic peptides corresponded mainly to the C2, V3 and CD4 binding sites of gp120 and some parts of the ectodomain of gp41. The reactivity of these peptides was tested by ELISA against different HIV-1-positive sera from different locations in India. For two of these predicted epitopes, the corresponding Indian consensus sequences (LAIERYLKQQLLGWG and DIIGDIRQAHCNISEDKWNET (subtype C were also synthesized and their reactivity was tested by ELISA. These peptides also distinguished HIV-1-positive sera of Indians with C subtype infections from sera from HIV-negative subjects.

Alterations in cholesterol metabolism restrict HIV-1 trans infection in nonprogressors.

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Rappocciolo, Giovanna; Jais, Mariel; Piazza, Paolo; Reinhart, Todd A; Berendam, Stella J; Garcia-Exposito, Laura; Gupta, Phalguni; Rinaldo, Charles R

2014-04-29

ABSTRACT HIV-1-infected nonprogressors (NP) inhibit disease progression for years without antiretroviral therapy. Defining the mechanisms for this resistance to disease progression could be important in determining strategies for controlling HIV-1 infection. Here we show that two types of professional antigen-presenting cells (APC), i.e., dendritic cells (DC) and B lymphocytes, from NP lacked the ability to mediate HIV-1 trans infection of CD4(+) T cells. In contrast, APC from HIV-1-infected progressors (PR) and HIV-1-seronegative donors (SN) were highly effective in mediating HIV-1 trans infection. Direct cis infection of T cells with HIV-1 was comparably efficient among NP, PR, and SN. Lack of HIV-1 trans infection in NP was linked to lower cholesterol levels and an increase in the levels of the reverse cholesterol transporter ABCA1 (ATP-binding cassette transporter A1) in APC but not in T cells. Moreover, trans infection mediated by APC from NP could be restored by reconstitution of cholesterol and by inhibiting ABCA1 by mRNA interference. Importantly, this appears to be an inherited trait, as it was evident in APC obtained from NP prior to their primary HIV-1 infection. The present study demonstrates a new mechanism wherein enhanced lipid metabolism in APC results in remarkable control of HIV-1 trans infection that directly relates to lack of HIV-1 disease progression. IMPORTANCE HIV-1 can be captured by antigen-presenting cells (APC) such as dendritic cells and transferred to CD4 helper T cells, which results in greatly enhanced viral replication by a mechanism termed trans infection. A small percentage of HIV-1-infected persons are able to control disease progression for many years without antiretroviral therapy. In our study, we linked this lack of disease progression to a profound inability of APC from these individuals to trans infect T cells. This effect was due to altered lipid metabolism in their APC, which appears to be an inherited trait. These

Production of a Dendritic Cell-Based Vaccine Containing Inactivated Autologous Virus for Therapy of Patients with Chronic Human Immunodeficiency Virus Type 1 Infection▿

OpenAIRE

Whiteside, Theresa L.; Piazza, Paolo; Reiter, Amanda; Stanson, Joanna; Connolly, Nancy C.; Rinaldo, Charles R.; Riddler, Sharon A.

2008-01-01

In preparation for a pilot clinical trial in patients with chronic human immunodeficiency virus type 1 (HIV-1) infection, a novel dendritic cell (DC)-based vaccine is being manufactured. The trial will test the hypothesis that isolated endogenous virus presented by DCs serves as a potent immunogen for activation of CD8+ and CD4+ T cells specific for a broad range of autologous HIV-1 antigens. Production of the vaccine under good manufacture practice conditions involves (i) autologous virus is...

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.

Pneumococcal pneumonia: clinical features, diagnosis and management in HIV-infected and HIV noninfected patients.

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Madeddu, Giordano; Fois, Alessandro Giuseppe; Pirina, Pietro; Mura, Maria Stella

2009-05-01

In this review, we focus on the clinical features, diagnosis and management of pneumococcal pneumonia in HIV-infected and noninfected patients, with particular attention to the most recent advances in this area. Classical clinical features are found in young adults, whereas atypical forms occur in immunocompromised patients including HIV-infected individuals. Bacteremic pneumococcal pneumonia is more frequently observed in HIV-infected and also in low-risk patients, according to the Pneumonia Severity Index (PSI). Pneumococcal pneumonia diagnostic process includes physical examination, radiologic findings and microbiologic diagnosis. However, etiologic diagnosis using traditional culture methods is difficult to obtain. In this setting, urinary antigen test, which recognizes Streptococcus pneumoniae cell wall C-polysaccharide, increases the probability of etiologic diagnosis. A correct management approach is crucial in reducing pneumococcal pneumonia mortality. The use of the PSI helps clinicians in deciding between inpatient and outpatient management in immunocompetent individuals, according to Infectious Diseases Society of America (IDSA)-American Thoracic Society (ATS) guidelines. Recent findings support PSI utility also in HIV-infected patients. Recently, efficacy of pneumococcal vaccine in reducing pneumococcal disease incidence has been evidenced in both HIV-infected and noninfected individuals. Rapid diagnosis and correct management together with implementation of preventive measures are crucial in order to reduce pneumococcal pneumonia related incidence and mortality in HIV-infected and noninfected patients.

21 CFR 660.40 - Hepatitis B Surface Antigen.

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2010-04-01

... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Hepatitis B Surface Antigen. 660.40 Section 660.40...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Hepatitis B Surface Antigen § 660.40 Hepatitis B Surface Antigen. (a) Proper name and definition. The proper name of this product...

HIV Structural Database

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SRD 102 HIV Structural Database (Web, free access)   The HIV Protease Structural Database is an archive of experimentally determined 3-D structures of Human Immunodeficiency Virus 1 (HIV-1), Human Immunodeficiency Virus 2 (HIV-2) and Simian Immunodeficiency Virus (SIV) Proteases and their complexes with inhibitors or products of substrate cleavage.

SAMHD1 restricts HIV-1 replication and regulates interferon production in mouse myeloid cells.

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Ruonan Zhang

Full Text Available SAMHD1 restricts the replication of HIV-1 and other retroviruses in human myeloid and resting CD4(+ T cells and that is counteracted in SIV and HIV-2 by the Vpx accessory protein. The protein is a phosphohydrolase that lowers the concentration of deoxynucleoside triphosphates (dNTP, blocking reverse transcription of the viral RNA genome. Polymorphisms in the gene encoding SAMHD1 are associated with Aicardi-Goutières Syndrome, a neurological disorder characterized by increased type-I interferon production. SAMHD1 is conserved in mammals but its role in restricting virus replication and controlling interferon production in non-primate species is not well understood. We show that SAMHD1 is catalytically active and expressed at high levels in mouse spleen, lymph nodes, thymus and lung. siRNA knock-down of SAMHD1 in bone marrow-derived macrophages increased their susceptibility to HIV-1 infection. shRNA knock-down of SAMHD1 in the murine monocytic cell-line RAW264.7 increased its susceptibility to HIV-1 and murine leukemia virus and increased the levels of the dNTP pool. In addition, SAMHD1 knock-down in RAW264.7 cells induced the production of type-I interferon and several interferon-stimulated genes, modeling the situation in Aicardi-Goutières Syndrome. Our findings suggest that the role of SAMHD1 in restricting viruses is conserved in the mouse. The RAW264.7 cell-line serves as a useful tool to study the antiviral and innate immune response functions of SAMHD1.

ABO and rhesus antigens in a cosmopolitan Nigeria population.

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Nwauche, C A; Ejele, O A

2004-01-01

Port Harcourt is a cosmopolitan city consisting of several ethnic groupings such as Ikwerre, Ijaw, Igbo, Ogonis, Efik-Ibibio, Edo, Yoruba, Hausa and foreign nationals. ABO and Rhesus D antigens were screened in this cross-sectional study with the aim of generating data that would assist in the running of an efficient blood transfusion service for a cosmopolitan city as Port Harcourt. Blood donors were sampled and screened for ABO and Rhesus D antigens at three Health facilities within Port Harcourt: University of Port Harcourt Teaching Hospital, Braithwaite Memorial Hospital and Orogbum Health centre. A total of 936 blood donors were tested in this study. The results of the ABO screening shows that blood group O was the highest with 527 (56.30%) followed by blood group A, B and lastly AB with 212 (22.65%), 178 (19.02%) and 18(2.10%) respectively. The highest contribution to blood group O was from the Ibos with 220 (23.50%) while the Ijaws gave the highest contribution of Rhesus "D" antigen with 370 (39.53%), closely followed by the Igbos with 334 (0.43%). Rhesus negativity values in this study was 7.26% of which the highest contributors were also the Ijaws with 33 (3.53%) and Igbos with 27(2.89%). The increased demand for safe blood calls for an efficient Blood, Transfusion Service at the local, state and national levels. It is hoped that the data generated in this study would assist in the planning and establishment of a functional Blood service that would not only meet the ever increasing demand for blood products, but also play a vital role in the control of HIV/AIDS and . Hepatitis B global scourge.

Immune Modulation of NYVAC-Based HIV Vaccines by Combined Deletion of Viral Genes that Act on Several Signalling Pathways

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Carmen Elena Gómez

2017-12-01

Full Text Available An HIV-1 vaccine continues to be a major target to halt the AIDS pandemic. The limited efficacy of the RV144 phase III clinical trial with the canarypox virus-based vector ALVAC and a gp120 protein component led to the conclusion that improved immune responses to HIV antigens are needed for a more effective vaccine. In non-human primates, the New York vaccinia virus (NYVAC poxvirus vector has a broader immunogenicity profile than ALVAC and has been tested in clinical trials. We therefore analysed the HIV immune advantage of NYVAC after removing viral genes that act on several signalling pathways (Toll-like receptors—TLR—interferon, cytokines/chemokines, as well as genes of unknown immune function. We generated a series of NYVAC deletion mutants and studied immune behaviour (T and B cell to HIV antigens and to the NYVAC vector in mice. Our results showed that combined deletion of selected vaccinia virus (VACV genes is a valuable strategy for improving the immunogenicity of NYVAC-based vaccine candidates. These immune responses were differentially modulated, positive or negative, depending on the combination of gene deletions. The deletions also led to enhanced antigen- or vector-specific cellular and humoral responses. These findings will facilitate the development of optimal NYVAC-based vaccines for HIV and other diseases.

The anti-HIV-1 effect of scutellarin

International Nuclear Information System (INIS)

Zhang Gaohong; Wang Qian; Chen Jijun; Zhang Xuemei; Tam, S.-C.; Zheng Yongtang

2005-01-01

Scutellarin was purified from the plant Erigeron breviscapus (Vant.) Hand.-Mazz. The activity against 3 strains of human immunodeficiency virus (HIV) was determined in vitro in this study. These were laboratory-derived virus (HIV-1 IIIB ), drug-resistant virus (HIV-1 74V ), and low-passage clinical isolated virus (HIV-1 KM018 ). From syncytia inhibition study, the EC 50 of scutellarin against HIV-1 IIIB direct infection in C8166 cells was 26 μM with a therapeutic index of 36. When the mode of infection changed from acute infection to cell-to-cell infection, this compound became even more potent and the EC 50 reduced to 15 μM. This suggested that cell fusion might be affected by this compound. By comparing the inhibitory effects on p24 antigen, scutellarin was also found to be active against HIV-1 74V (EC 50 253 μM) and HIV-1 KM018 (EC 50 136 μM) infection with significant difference in potency. The mechanism of its action was also explored in this study. At a concentration of 433 μM, scutellarin inhibited 48% of the cell free recombinant HIV-1 RT activity. It also caused 82% inhibition of HIV-1 particle attachment and 45% inhibition of fusion at the concentrations of 54 μM. In summary, scutellarin was found to inhibit several strains of HIV-1 replication with different potencies. It appeared to inhibit HIV-1 RT activity, HIV-1 particle attachment and cell fusion. These are essential activities for viral transmission and replication

Heterophilic interference in specimens yielding false-reactive results on the Abbott 4th generation ARCHITECT HIV Ag/Ab Combo assay.

Science.gov (United States)

Lavoie, S; Caswell, D; Gill, M J; Kadkhoda, K; Charlton, C L; Levett, P N; Hatchette, T; Garceau, R; Maregmen, J; Mazzulli, T; Needle, R; Kadivar, K; Kim, J

2018-04-12

False-reactivity in HIV-negative specimens has been detected in HIV fourth-generation antigen/antibody or 'combo' assays which are able to detect both anti-HIV-1/HIV-2 antibodies and HIV-1 antigen. We sought to characterize these specimens and determine the effect of heterophilic interference. Specimens previously testing as false-reactive on the Abbott ARCHITECT HIV Ag/Ab combo assay and re-tested on a different (Siemens ADVIA Centaur HIV Ag/Ab) assay. A subset of these specimens were also pre-treated with heterophilic blocking agents and re-tested on the Abbott assay. Here we report that 95% (252/264) of clinical specimens that were repeatedly reactive on the Abbott ARCHITECT HIV Ag/Ab combo assay (S/Co range, 0.94-678) were negative when re-tested on a different fourth generation HIV combo assay (Siemens ADVIA Centaur HIV Ag/Ab). All 264 samples were subsequently confirmed to be HIV negative. On a small subset (57) of specimens with available volume, pre-treatment with two different reagents (HBT; Heterophilic Blocking Tube, NABT; Non-Specific Blocking Tube) designed to block heterophilic antibody interference either eliminated (HBT) or reduced (NABT) the false reactivity when re-tested on the ARCHITECT HIV Ag/Ab combo assay. Our results suggest that the Abbott ARCHITECT HIV Ag/Ab combo assay can be prone to heterophilic antibody interference. Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.

Production of vaccines for treatment of infectious diseases by transgenic plants

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Kristina LEDL

2016-04-01

Full Text Available Since the first pathogen antigen was expressed in transgenic plants with the aim of producing edible vaccine in early 1990s, transgenic plants have become a well-established expression system for production of alternative vaccines against various human and animal infectious diseases. The main focus of plant expression systems in the last five years has been on improving expression of well-studied antigens such as porcine reproductive and respiratory syndrome (PRRSV, bovine viral diarrhea disease virus (BVDV, footh and mouth disease virus (FMDV, hepatitis B surface antigen (HBsAg, rabies G protein, rotavirus, Newcastle disease virus (NDV, Norwalk virus capsid protein (NVCP, avian influenza virus H5N1, Escherichia coli heat-labile enterotoxin subunit B (LT-B, cholera toxin B (CT-B, human immunodeficiency virus (HIV, artherosclerosis, ebola and anthrax. Significant increases in expression have been obtained using improved expression vectors, different plant species and transformation methods.

Expanded cellular clones carrying replication-competent HIV-1 persist, wax, and wane.

Science.gov (United States)

Wang, Zheng; Gurule, Evelyn E; Brennan, Timothy P; Gerold, Jeffrey M; Kwon, Kyungyoon J; Hosmane, Nina N; Kumar, Mithra R; Beg, Subul A; Capoferri, Adam A; Ray, Stuart C; Ho, Ya-Chi; Hill, Alison L; Siliciano, Janet D; Siliciano, Robert F

2018-03-13

The latent reservoir for HIV-1 in resting CD4 + T cells is a major barrier to cure. Several lines of evidence suggest that the latent reservoir is maintained through cellular proliferation. Analysis of this proliferative process is complicated by the fact that most infected cells carry defective proviruses. Additional complications are that stimuli that drive T cell proliferation can also induce virus production from latently infected cells and productively infected cells have a short in vivo half-life. In this ex vivo study, we show that latently infected cells containing replication-competent HIV-1 can proliferate in response to T cell receptor agonists or cytokines that are known to induce homeostatic proliferation and that this can occur without virus production. Some cells that have proliferated in response to these stimuli can survive for 7 d while retaining the ability to produce virus. This finding supports the hypothesis that both antigen-driven and cytokine-induced proliferation may contribute to the stability of the latent reservoir. Sequencing of replication-competent proviruses isolated from patients at different time points confirmed the presence of expanded clones and demonstrated that while some clones harboring replication-competent virus persist longitudinally on a scale of years, others wax and wane. A similar pattern is observed in longitudinal sampling of residual viremia in patients. The observed patterns are not consistent with a continuous, cell-autonomous, proliferative process related to the HIV-1 integration site. The fact that the latent reservoir can be maintained, in part, by cellular proliferation without viral reactivation poses challenges to cure.

Loss of circulating CD4 T cells with B cell helper function during chronic HIV infection.

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Kristin L Boswell

2014-01-01

Full Text Available The interaction between follicular T helper cells (TFH and B cells in the lymph nodes and spleen has a major impact on the development of antigen-specific B cell responses during infection or vaccination. Recent studies described a functional equivalent of these cells among circulating CD4 T cells, referred to as peripheral TFH cells. Here, we characterize the phenotype and in vitro B cell helper activity of peripheral TFH populations, as well as the effect of HIV infection on these populations. In co-culture experiments we confirmed CXCR5+ cells from HIV-uninfected donors provide help to B cells and more specifically, we identified a CCR7(highCXCR5(highCCR6(highPD-1(high CD4 T cell population that secretes IL-21 and enhances isotype-switched immunoglobulin production. This population is significantly decreased in treatment-naïve, HIV-infected individuals and can be recovered after anti-retroviral therapy. We found impaired immunoglobulin production in co-cultures from HIV-infected individuals and found no correlation between the frequency of peripheral TFH cells and memory B cells, or with neutralization activity in untreated HIV infection in our cohort. Furthermore, we found that within the peripheral TFH population, the expression level of TFH-associated genes more closely resembles a memory, non-TFH population, as opposed to a TFH population. Overall, our data identify a heterogeneous population of circulating CD4 T cells that provides in vitro help to B cells, and challenges the origin of these cells as memory TFH cells.

[Studies on antigencity of human immunodeficiency virus type 1 (HIV-1) external glycoprotein as well as its expression in Pichia pastoris].

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Zhao, Li-Hui; Yu, Xiang-Hui; Jiang, Chun-Lai; Wu, Yong-Ge; Shen, Jia-Cong; Kong, Wei

2007-05-01

Based on the computer simulation, we analyzed hydrophobicity, potential epitope of recombined subtypes HIV-1 Env protein (851 amino acids) from Guangxi in China. Compared with conservative peptides of other subtypes in env protein, three sequences (469-511aa, 538-674aa, 700-734aa) were selected to recombine into a chimeric gene that codes three conservative epitope peptides with stronger antigencity, and was constructed in the yeast expression plasmid pPICZB. Chimeric proteins were expressed in Pichia pastoris under the induction of methanol, and were analyzed by SDS-PAGE and Westernblot. The results showed that fusion proteins of three-segment antigen were expressed in Pichia pastoris and that specific protein band at the site of 40kD was target protein, which is interacted with HIV-1 serum. The target proteins were purified by metal Ni-sepharose 4B, and were demonstrated to possess good antigenic specificity from the data of ELISA. This chimeric antigen may be used as research and developed into HIV diagnostic reagents.

Mimotopes selected by biopanning with high-titer HIV-neutralizing antibodies in plasma from Chinese slow progressors

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Xiaoli Zhang

Full Text Available OBJECTIVE: One approach to identifying HIV-1 vaccine candidates is to dissect the natural antiviral immune response in treatment-naïve individuals infected for over ten years, considered slow progressor patients (SPs. It is suspected that SP plasma has strongly neutralizing antibodies (NAb targeting specific HIV viral epitopes. METHODS: NAbs levels of 11 HIV-1-infected SPs were detected by PBMC-based neutralization assays. To investigate SP NAb epitope, this study used a biopanning approach to obtain mimotopes of HIV-1 that were recognized by SP plasma NAbs. IgG was purified from hightiter NAb SP plasma, and used as the ligand for three rounds of biopanning to select HIV-specific mimotopes from a phage-displayed random peptide library. Double-antibody sandwich ELISA, competitive inhibition assays, and peptide sequence analysis were used to evaluate the characteristics of phage-borne mimotopes. RESULTS: SPs had significantly more plasma neutralizing activity than typical progressors (TPs (p = 0.04. P2 and P9 plasma, which have highest-titer HIV-NAb, were selected as ligands for biopanning. After three rounds of biopanning, 48 phage clones were obtained, of which 22 clones were consistent with requirement, binding with HIV-1 positive plasma and unbinding with HIV-1 negative plasma. Compared with linear HIV-1 protein sequence and HIV-1 protein structure files, only 12 clones were possible linear mimotopes of NAbs. In addition, the C40 clone located in gp41 CHR was found to be a neutralizing epitope, which could inhibit pooled HIV-1 positive plasma reaction. CONCLUSION: Biopanning of serum IgG can yield mimotopes of HIV-1-related antigen epitopes. This methodology provides a basis for exploration into HIV-1-related antigen-antibody interactions and furthers NAb immunotherapy and vaccine design.

Changing of expression level of fas-antigen (CD95), cytokines synthesis and production after irradiation in low doses

International Nuclear Information System (INIS)

Kalinina, N.M.; Solntceva, O.S.; Bytchkova, N.V.; Nikiforov, A.M.

1997-01-01

It is known that bone marrow progenitor (CD34+), tymocytes and peripheral blood lymphocytes (PBL) are most radiosensitive than other cell types. Even low doses of radiation induce apoptosis. The investigators suggest that it is possible relationship between synthesis and production of cytokines and apoptotic process. With the purpose to determine correlation between expression of Fas-antigen and synthesis of cytokines after low doses irradiation the experiments by irradiation PBL of healthy persons in vitro were held. Cells were X-irradiated by 12,5, 25 and 50 cGy. In consequence of the experiments increasing of Fas-antigen was revealed. This increasing correlated with changing in synthesis and production of cytokines. Also the Chernobyl's accident liquidators (CAL) were investigated. After comparison data in the group CAL (I) with data in the control group (II) increasing of Fas-antigen expression was revealed. Also in I group was discovered increasing of the cell number sinthesied interleukine-4 (IL-4) and interleukine-6 (IL-6). Interleukine-lβ (IL-1 β) producing pell were decreased. These changes have been correlated with degree of immunodeficiency at CAL. These data allow to consider the apoptosis as cell mechanism included in pathogenesis of diseases, which can be showed later long time after irradiation. (author)

Comparison of a Clinical Prediction Rule and a LAM Antigen-Detection Assay for the Rapid Diagnosis of TBM in a High HIV Prevalence Setting

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Patel, Vinod B.; Singh, Ravesh; Connolly, Cathy; Kasprowicz, Victoria; Zumla, Allimudin; Ndungu, Thumbi; Dheda, Keertan

2010-01-01

Background/Objective The diagnosis of tuberculous meningitis (TBM) in resource poor TB endemic environments is challenging. The accuracy of current tools for the rapid diagnosis of TBM is suboptimal. We sought to develop a clinical-prediction rule for the diagnosis of TBM in a high HIV prevalence setting, and to compare performance outcomes to conventional diagnostic modalities and a novel lipoarabinomannan (LAM) antigen detection test (Clearview-TB®) using cerebrospinal fluid (CSF). Methods Patients with suspected TBM were classified as definite-TBM (CSF culture or PCR positive), probable-TBM and non-TBM. Results Of the 150 patients, 84% were HIV-infected (median [IQR] CD4 count = 132 [54; 241] cells/µl). There were 39, 55 and 54 patients in the definite, probable and non-TBM groups, respectively. The LAM sensitivity and specificity (95%CI) was 31% (17;48) and 94% (85;99), respectively (cut-point ≥0.18). By contrast, smear-microscopy was 100% specific but detected none of the definite-TBM cases. LAM positivity was associated with HIV co-infection and low CD4 T cell count (CD4200 cells/µl; p = 0.03). The sensitivity and specificity in those with a CD4<100 cells/µl was 50% (27;73) and 95% (74;99), respectively. A clinical-prediction rule ≥6 derived from multivariate analysis had a sensitivity and specificity (95%CI) of 47% (31;64) and 98% (90;100), respectively. When LAM was combined with the clinical-prediction-rule, the sensitivity increased significantly (p<0.001) to 63% (47;68) and specificity remained high at 93% (82;98). Conclusions Despite its modest sensitivity the LAM ELISA is an accurate rapid rule-in test for TBM that has incremental value over smear-microscopy. The rule-in value of LAM can be further increased by combination with a clinical-prediction rule, thus enhancing the rapid diagnosis of TBM in HIV-infected persons with advanced immunosuppression. PMID:21203513

Mini-review: Strategies for Variation and Evolution of Bacterial Antigens

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Foley, Janet

2015-01-01

Across the eubacteria, antigenic variation has emerged as a strategy to evade host immunity. However, phenotypic variation in some of these antigens also allows the bacteria to exploit variable host niches as well. The specific mechanisms are not shared-derived characters although there is considerable convergent evolution and numerous commonalities reflecting considerations of natural selection and biochemical restraints. Unlike in viruses, mechanisms of antigenic variation in most bacteria involve larger DNA movement such as gene conversion or DNA rearrangement, although some antigens vary due to point mutations or modified transcriptional regulation. The convergent evolution that promotes antigenic variation integrates various evolutionary forces: these include mutations underlying variant production; drift which could remove alleles especially early in infection or during life history phases in arthropod vectors (when the bacterial population size goes through a bottleneck); selection not only for any particular variant but also for the mechanism for the production of variants (i.e., selection for mutability); and overcoming negative selection against variant production. This review highlights the complexities of drivers of antigenic variation, in particular extending evaluation beyond the commonly cited theory of immune evasion. A deeper understanding of the diversity of purpose and mechanisms of antigenic variation in bacteria will contribute to greater insight into bacterial pathogenesis, ecology and coevolution with hosts. PMID:26288700

Production of Antigens and Antibodies for Diagnosis of Arbovirus Diseases.

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1994-05-20

for Germiston, Qalyub, Sicilian, vesicular stomatitis Indiana, and Ganjam viruses. The antigens were inactivated with beta-propiolactone. Rabbits were...vesicular stomatitis Indiana, and Ganjam viruses. The antigens were inactivated with beta-propiolactone. Rabbits were immunized successfully intravenously...370 sm4 6 229 Sicilian Sabin sm37,Vero2 1 23 VS-Indiana Ind. Lab sm7 1 45 Ganjam IG 619 sm5 1 67 Additionally, 22 viruses were passaged in baby mice

Human cellular restriction factors that target HIV-1 replication

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Jeang Kuan-Teh

2009-09-01

Full Text Available Abstract Recent findings have highlighted roles played by innate cellular factors in restricting intracellular viral replication. In this review, we discuss in brief the activities of apolipoprotein B mRNA-editing enzyme 3G (APOBEC3G, bone marrow stromal cell antigen 2 (BST-2, cyclophilin A, tripartite motif protein 5 alpha (Trim5α, and cellular microRNAs as examples of host restriction factors that target HIV-1. We point to countermeasures encoded by HIV-1 for moderating the potency of these cellular restriction functions.

Recognition of HIV-1 peptides by host CTL is related to HIV-1 similarity to human proteins.

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Morgane Rolland

Full Text Available BACKGROUND: While human immunodeficiency virus type 1 (HIV-1-specific cytotoxic T lymphocytes preferentially target specific regions of the viral proteome, HIV-1 features that contribute to immune recognition are not well understood. One hypothesis is that similarities between HIV and human proteins influence the host immune response, i.e., resemblance between viral and host peptides could preclude reactivity against certain HIV epitopes. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed the extent of similarity between HIV-1 and the human proteome. Proteins from the HIV-1 B consensus sequence from 2001 were dissected into overlapping k-mers, which were then probed against a non-redundant database of the human proteome in order to identify segments of high similarity. We tested the relationship between HIV-1 similarity to host encoded peptides and immune recognition in HIV-infected individuals, and found that HIV immunogenicity could be partially modulated by the sequence similarity to the host proteome. ELISpot responses to peptides spanning the entire viral proteome evaluated in 314 individuals showed a trend indicating an inverse relationship between the similarity to the host proteome and the frequency of recognition. In addition, analysis of responses by a group of 30 HIV-infected individuals against 944 overlapping peptides representing a broad range of individual HIV-1B Nef variants, affirmed that the degree of similarity to the host was significantly lower for peptides with reactive epitopes than for those that were not recognized. CONCLUSIONS/SIGNIFICANCE: Our results suggest that antigenic motifs that are scarcely represented in human proteins might represent more immunogenic CTL targets not selected against in the host. This observation could provide guidance in the design of more effective HIV immunogens, as sequences devoid of host-like features might afford superior immune reactivity.

Strategies for induction of catalytic antibodies toward HIV-1 glycoprotein gp120 in autoimmune prone mice.

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Durova, Oxana M; Vorobiev, Ivan I; Smirnov, Ivan V; Reshetnyak, Andrew V; Telegin, Georgy B; Shamborant, Olga G; Orlova, Nadezda A; Genkin, Dmitry D; Bacon, Andrew; Ponomarenko, Natalia A; Friboulet, Alain; Gabibov, Alexander G

2009-11-01

Tremendous efforts to produce an efficient vaccine for HIV infection have been unsuccessful. The ability of HIV to utilize sophisticated mechanisms to escape killing by host immune system rises dramatic problems in the development of antiviral therapeutics. The HIV infection proceeds by interaction of coat viral glycoprotein gp120 trimer with CD4(+) receptor of the lymphocyte. Thus this surface antigen may be regarded as a favorable target for immunotherapy. In the present study, we have developed three different strategies to produce gp120-specific response in autoimmune prone mice (SJL strain) as potential tools for production "catalytic vaccine". Therefore (i) reactive immunization by peptidylphosphonate, structural part of the coat glycoprotein, (ii) immunization by engineered fused epitopes of gp120 and encephalogenic peptide, a part of myelin basic protein, and (iii) combined vaccination by DNA and corresponding gp120 fragments incorporated into liposomes were investigated. In the first two cases monoclonal antibodies and their recombinant fragments with amidolytic and gp120-specific proteolytic activities were characterized. In the last case, catalytic antibodies with virus neutralizing activity proved in cell line models were harvested.

Detection of Avian Antigen-Specific T Cells Induced by Viral Vaccines

DEFF Research Database (Denmark)

Dalgaard, Tina Sørensen; Norup, Liselotte Rothmann; Juul-Madsen, Helle Risdahl

2016-01-01

Live attenuated viral vaccines are widely used in commercial poultry production, but the development of new effective inactivated/subunit vaccines is needed. Studies of avian antigen-specific T cells are primarily based on analyses ex vivo after activating the cells with recall antigen. There is ......Live attenuated viral vaccines are widely used in commercial poultry production, but the development of new effective inactivated/subunit vaccines is needed. Studies of avian antigen-specific T cells are primarily based on analyses ex vivo after activating the cells with recall antigen...

Contrasting roles for TLR ligands in HIV-1 pathogenesis.

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Beda Brichacek

2010-09-01

Full Text Available The first line of a host's response to various pathogens is triggered by their engagement of cellular pattern recognition receptors (PRRs. Binding of microbial ligands to these receptors leads to the induction of a variety of cellular factors that alter intracellular and extracellular environment and interfere directly or indirectly with the life cycle of the triggering pathogen. Such changes may also affect any coinfecting microbe. Using ligands to Toll-like receptors (TLRs 5 and 9, we examined their effect on human immunodeficiency virus (HIV-1 replication in lymphoid tissue ex vivo. We found marked differences in the outcomes of such treatment. While flagellin (TLR5 agonist treatment enhanced replication of CC chemokine receptor 5 (CCR 5-tropic and CXC chemokine receptor 4 (CXCR4-tropic HIV-1, treatment with oligodeoxynucleotide (ODN M362 (TLR9 agonist suppressed both viral variants. The differential effects of these TLR ligands on HIV-1 replication correlated with changes in production of CC chemokines CCL3, CCL4, CCL5, and of CXC chemokines CXCL10, and CXCL12 in the ligand-treated HIV-1-infected tissues. The nature and/or magnitude of these changes were dependent on the ligand as well as on the HIV-1 viral strain. Moreover, the tested ligands differed in their ability to induce cellular activation as evaluated by the expression of the cluster of differentiation markers (CD 25, CD38, CD39, CD69, CD154, and human leukocyte antigen D related (HLA-DR as well as of a cell proliferation marker, Ki67, and of CCR5. No significant effect of the ligand treatment was observed on apoptosis and cell death/loss in the treated lymphoid tissue ex vivo. Our results suggest that binding of microbial ligands to TLRs is one of the mechanisms that mediate interactions between coinfected microbes and HIV-1 in human tissues. Thus, the engagement of appropriate TLRs by microbial molecules or their mimetic might become a new strategy for HIV therapy or prevention.

Cross-reactive microbial peptides can modulate HIV-specific CD8+ T cell responses.

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Christopher W Pohlmeyer

Full Text Available Heterologous immunity is an important aspect of the adaptive immune response. We hypothesized that this process could modulate the HIV-1-specific CD8+ T cell response, which has been shown to play an important role in HIV-1 immunity and control. We found that stimulation of peripheral blood mononuclear cells (PBMCs from HIV-1-positive subjects with microbial peptides that were cross-reactive with immunodominant HIV-1 epitopes resulted in dramatic expansion of HIV-1-specific CD8+ T cells. Interestingly, the TCR repertoire of HIV-1-specific CD8+ T cells generated by ex vivo stimulation of PBMCs using HIV-1 peptide was different from that of cells stimulated with cross-reactive microbial peptides in some HIV-1-positive subjects. Despite these differences, CD8+ T cells stimulated with either HIV-1 or cross-reactive peptides effectively suppressed HIV-1 replication in autologous CD4+ T cells. These data suggest that exposure to cross-reactive microbial antigens can modulate HIV-1-specific immunity.

Allosensibilisation to erythrocyte antigens (literature review

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N. V. Mineeva

2015-01-01

Full Text Available In this article literature review of the causes of allosensibilisation to erythrocyte antigens are presented. It is shown that the ability to produce antierythrocyte antibodies is affected by many factors, principal of whom it is difficult to identify. For the allosensibilisation development requires genetically determined differences in erythrocyte antigens phenotypes of donor and recipient, mother and fetus, which can lead to immune response and antibodies production. The biochemical nature of erythrocyte antigens, antigen dose (the amount of transfused doses, the number of antigens determinants on donor and fetus erythrocytes, the number of pregnancies are important. Individual patient characteristics: age, gender, diseases, the use of immunosuppressive therapy and the presence of inflammatory processes, are also relevant. Note that antibody to one erythrocyte antigens have clinical value, and to the other – have no. The actual data about frequency of clinically significant antibodies contribute to the development of post-transfusion hemolytic complications prophylaxis as well as the improvement of laboratory diagnosis of hemolytic disease of the newborn in the presence of maternal antierythrocyte antibodies.

Schistosoma mansoni and HIV infection in a Ugandan population with high HIV and helminth prevalence.

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Sanya, Richard E; Muhangi, Lawrence; Nampijja, Margaret; Nannozi, Victoria; Nakawungu, Prossy Kabuubi; Abayo, Elson; Webb, Emily L; Elliott, Alison M

2015-09-01

Recent reports suggest that Schistosoma infection may increase the risk of acquiring human immunodeficiency virus (HIV). We used data from a large cross-sectional study to investigate whether Schistosoma mansoni infection is associated with increased HIV prevalence. We conducted a household survey of residents in island fishing communities in Mukono district, Uganda, between October 2012 and July 2013. HIV status was assessed using rapid test kits. Kato-Katz (KK) stool tests and urine-circulating cathodic antigen (CCA) were used to test for Schistosoma infection. Multivariable logistic regression, allowing for the survey design, was used to investigate the association between S. mansoni infection and HIV infection. Data from 1412 participants aged 13 years and older were analysed (mean age 30.3 years, 45% female). The prevalence of HIV was 17.3%. Using the stool Kato-Katz technique on a single sample, S. mansoni infection was detected in 57.2% (719/1257) of participants; urine CCA was positive in 73.8% (478/650) of those tested. S. mansoni infection was not associated with HIV infection. [KK (aOR = 1.04; 95% CI: 0.74-1.47, P = 0.81), CCA (aOR = 1.53; 95% CI: 0.78-3.00, P = 0.19)]. The median S. mansoni egg count per gram was lower in the HIV-positive participants (P = 0.005). These results add to the evidence that S. mansoni has little effect on HIV transmission, but may influence egg excretion. © 2015 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.

Performance of the BioPlex 2200 HIV Ag-Ab assay for identifying acute HIV infection.

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Eshleman, Susan H; Piwowar-Manning, Estelle; Sivay, Mariya V; Debevec, Barbara; Veater, Stephanie; McKinstry, Laura; Bekker, Linda-Gail; Mannheimer, Sharon; Grant, Robert M; Chesney, Margaret A; Coates, Thomas J; Koblin, Beryl A; Fogel, Jessica M

Assays that detect HIV antigen (Ag) and antibody (Ab) can be used to screen for HIV infection. To compare the performance of the BioPlex 2200 HIV Ag-Ab assay and two other Ag/Ab combination assays for detection of acute HIV infection. Samples were obtained from 24 individuals (18 from the US, 6 from South Africa); these individuals were classified as having acute infection based on the following criteria: positive qualitative RNA assay; two negative rapid tests; negative discriminatory test. The samples were tested with the BioPlex assay, the ARCHITECT HIV Ag/Ab Combo test, the Bio-Rad GS HIV Combo Ag-Ab EIA test, and a viral load assay. Twelve (50.0%) of 24 samples had RNA detected only ( > 40 to 13,476 copies/mL). Ten (43.5%) samples had reactive results with all three Ag/Ab assays, one sample was reactive with the ARCHITECT and Bio-Rad assays, and one sample was reactive with the Bio-Rad and BioPlex assays. The 11 samples that were reactive with the BioPlex assay had viral loads from 83,010 to >750,000 copies/mL; 9/11 samples were classified as Ag positive/Ab negative by the BioPlex assay. Detection of acute HIV infection was similar for the BioPlex assay and two other Ag/Ab assays. All three tests were less sensitive than a qualitative RNA assay and only detected HIV Ag when the viral load was high. The BioPlex assay detected acute infection in about half of the cases, and identified most of those infections as Ag positive/Ab negative. Copyright © 2018 Elsevier B.V. All rights reserved.

HIV-1 transgenic rats develop T cell abnormalities

International Nuclear Information System (INIS)

Reid, William; Abdelwahab, Sayed; Sadowska, Mariola; Huso, David; Neal, Ashley; Ahearn, Aaron; Bryant, Joseph; Gallo, Robert C.; Lewis, George K.; Reitz, Marvin

2004-01-01

HIV-1 infection leads to impaired antigen-specific T cell proliferation, increased susceptibility of T cells to apoptosis, progressive impairment of T-helper 1 (Th1) responses, and altered maturation of HIV-1-specific memory cells. We have identified similar impairments in HIV-1 transgenic (Tg) rats. Tg rats developed an absolute reduction in CD4 + and CD8 + T cells able to produce IFN-γ following activation and an increased susceptibility of T cells to activation-induced apoptosis. CD4 + and CD8 + effector/memory (CD45RC - CD62L - ) pools were significantly smaller in Tg rats compared to non-Tg controls, although the converse was true for the naieve (CD45RC + CD62L + ) T cell pool. Our interpretation is that the HIV transgene causes defects in the development of T cell effector function and generation of specific effector/memory T cell subsets, and that activation-induced apoptosis may be an essential factor in this process

Molecular HIV screening.

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Bourlet, Thomas; Memmi, Meriam; Saoudin, Henia; Pozzetto, Bruno

2013-09-01

Nuclear acid testing is more and more used for the diagnosis of infectious diseases. This paper focuses on the use of molecular tools for HIV screening. The term 'screening' will be used under the meaning of first-line HIV molecular techniques performed on a routine basis, which excludes HIV molecular tests designed to confirm or infirm a newly discovered HIV-seropositive patient or other molecular tests performed for the follow-up of HIV-infected patients. The following items are developed successively: i) presentation of the variety of molecular tools used for molecular HIV screening, ii) use of HIV molecular tools for the screening of blood products, iii) use of HIV molecular tools for the screening of organs and tissue from human origin, iv) use of HIV molecular tools in medically assisted procreation and v) use of HIV molecular tools in neonates from HIV-infected mothers.

HLA-DQBl*0402 alleles polymorphisms detected in Javanese HIV patients with positive anti-Toxoplasma gondii IgM

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Sari, Yulia; Haryati, Sri; Prasetyo, Afiono Agung; Hartono, Adnan, Zainal Arifin

2017-02-01

The human leukocyte antigen (HLA)-DQB1 gene polymorphisms may associated with the infection risk of Toxoplasma gondii in HIV patients. The HLA-DQB1*0402 in HIV-1-positive patients could be considered risk factors for developing neurological opportunistic infections, mainly Toxoplasma encephalitis. However, the HLA-DQB1*0402 gene polymorphisms status in the Javanese HIV patients is unknown. This study evaluated the prevalence of HLA-DQB*0402 alleles polymorphisms in Javanese HIV patients with positive anti-Toxoplasma gondii IgM status. Since 2009 our research group performing a molecular epidemiology of blood borne viruses in Central Java Indonesia, by collecting the epidemiological and clinical data from the high risk communities. All blood samples were screened for blood borne pathogens by serological and molecular assays including for HIV and Toxoplasma gondii. The genomic DNA was isolated from the whole blood samples. Genetic polymorphisms of HLA-DQB1*0402 alleles were detected with polymerase chain reaction-sequence-specific primers (PCR-SSPs) technique. The genotypes were defined according to generated fragment patterns in the agarose gel electrophoresis analysis of PCR products. All of the samples were tested at least in duplicate. HLA-DQB1*0402 alleles were detected in 20.8% (16/77) patients and not detected in all HIV positive samples with negative anti-Toxoplasma gondii IgM status (n= 200). The HLA-DQB1*0402 alleles polymorphisms were detected in Javanese HIV patients with positive anti-Toxoplasma gondii IgM. The polymorphisms found may have association with the infection risk of Toxoplasma gondii in HIV patients.

Enhancement of the priming efficacy of DNA vaccines encoding dendritic cell-targeted antigens by synergistic toll-like receptor ligands

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Kornbluth Richard S

2009-08-01

Full Text Available Abstract Background Targeting of protein antigens to dendritic cells (DC via the DEC205 receptor enhances presentation of antigen-derived peptides on MHC-I and MHC-II molecules and, in the presence of costimulatory signals, antigen-specific immune responses. The immunogenicity and efficacy of DNA vaccination can also be enhanced by fusing the encoded antigen to single chain antibodies directed against DEC205. To further improve this strategy, we evaluated different toll-like receptor ligands (TLR and CD40 ligands (CD40L as adjuvants for DNA vaccines encoding a DEC205-single-chain antibody fused to the ovalbumin model antigen or HIV-1 Gag and assessed the priming efficacy of DNA in a DNA prime adenoviral vector boost immunization regimen. Results Mice were primed with the adjuvanted DEC-205 targeted DNA vaccines and boosted with adenoviral vectors encoding the same antigens. CD8+ T cell responses were determined after the adenoviral booster immunization, to determine how well the different DNA immunization regimens prime for the adenoviral boost. In the absence of adjuvants, targeting of DNA-encoded ovalbumin to DCs suppressed CD8+ T-cell responses after the adenoviral booster immunization. CD8+ T-cell responses to the DEC205 targeted DNA vaccines increased only slightly by adding either the TLR-9 ligand CpG, the TLR-3 ligand Poly I:C, or CD40 ligand expression plasmids. However, the combination of both TLR-ligands led to a strong enhancement of CD8+ T-cell responses compared to a non-targeted DNA vaccine. This finding was confirmed using HIV Gag as antigen. Conclusion Although DNA prime adenoviral vector boost immunizations belong to the strongest inducers of cytotoxic T cell responses in different animal models and humans, the CD8+ T cell responses can be further improved by targeting the DNA encoded antigen to DEC205 in the presence of synergistic TLR ligands CpG and Poly I:C.

Long-term nonprogression and broad HIV-1-specific proliferative T-cell responses

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Nesrina eImami

2013-03-01

Full Text Available Complex mechanisms underlying the maintenance of fully functional, proliferative, HIV-1-specific T-cell responses involve processes from early T-cell development through to the final stages of T-cell differentiation and antigen recognition. Virus-specific proliferative CD4 and CD8 T-cell responses, important for the control of infection, are observed in some HIV-1+ patients during early stages of disease, and are maintained in long-term nonprogressing subjects. In the vast majority of HIV-1+ patients, full immune functionality is lost when proliferative HIV-1-specific T-cell responses undergo a variable progressive decline throughout the course of chronic infection. This appears irreparable despite administration of potent combination antiretroviral therapy, which to date is non-curative, necessitating life-long administration and the development of effective, novel, therapeutic interventions. While a sterilising cure, involving clearance of virus from the host, remains a primary aim, a functional cure may be a more feasible goal with considerable impact on worldwide HIV-1 infection. Such an approach would enable long-term co-existence of host and virus in the absence of toxic and costly drugs. Effective immune homeostasis coupled with a balanced response appropriately targeting conserved viral antigens, in a manner that avoids hyperactivation and exhaustion, may prove to be the strongest correlate of durable viral control. This review describes novel concepts underlying full immune functionality in the context of HIV-1 infection, which may be utilised in future strategies designed to improve upon existing therapy. The aim will be to induce long-term nonprogressor or elite controller status in every infected host, through immune-mediated control of viraemia and reduction of viral reservoirs, leading to lower HIV-1 transmission rates.

Engineering antigen-specific T cells from genetically modified human hematopoietic stem cells in immunodeficient mice.

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Scott G Kitchen

Full Text Available There is a desperate need for effective therapies to fight chronic viral infections. The immune response is normally fastidious at controlling the majority of viral infections and a therapeutic strategy aimed at reestablishing immune control represents a potentially powerful approach towards treating persistent viral infections. We examined the potential of genetically programming human hematopoietic stem cells to generate mature CD8+ cytotoxic T lymphocytes that express a molecularly cloned, "transgenic" human anti-HIV T cell receptor (TCR. Anti-HIV TCR transduction of human hematopoietic stem cells directed the maturation of a large population of polyfunctional, HIV-specific CD8+ cells capable of recognizing and killing viral antigen-presenting cells. Thus, through this proof-of-concept we propose that genetic engineering of human hematopoietic stem cells will allow the tailoring of effector T cell responses to fight HIV infection or other diseases that are characterized by the loss of immune control.

Dendritic cell immunotherapy for HIV infection: from theory to reality.

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Oshiro, Telma Miyuki; de Almeida, Alexandre; da Silva Duarte, Alberto José

2009-11-01

Knowledge concerning the immunology of dendritic cells (DCs) accumulated over the last few decades and the development of methodologies to generate and manipulate these cells in vitro has made their therapeutic application a reality. Currently, clinical protocols for DC-based therapeutic vaccine in HIV-infected individuals show that it is a safe and promising approach. Concomitantly, important advances continue to be made in the development of methodologies to optimize DC acquisition, as well as the selection of safe, immunogenic HIV antigens and the evaluation of immune response in treated individuals.

Direct and dynamic detection of HIV-1 in living cells.

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Jonas Helma

Full Text Available In basic and applied HIV research, reliable detection of viral components is crucial to monitor progression of infection. While it is routine to detect structural viral proteins in vitro for diagnostic purposes, it previously remained impossible to directly and dynamically visualize HIV in living cells without genetic modification of the virus. Here, we describe a novel fluorescent biosensor to dynamically trace HIV-1 morphogenesis in living cells. We generated a camelid single domain antibody that specifically binds the HIV-1 capsid protein (CA at subnanomolar affinity and fused it to fluorescent proteins. The resulting fluorescent chromobody specifically recognizes the CA-harbouring HIV-1 Gag precursor protein in living cells and is applicable in various advanced light microscopy systems. Confocal live cell microscopy and super-resolution microscopy allowed detection and dynamic tracing of individual virion assemblies at the plasma membrane. The analysis of subcellular binding kinetics showed cytoplasmic antigen recognition and incorporation into virion assembly sites. Finally, we demonstrate the use of this new reporter in automated image analysis, providing a robust tool for cell-based HIV research.

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

African Journals Online (AJOL)

TNHJOURNALPH

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.

Anti-HIV-1 activity of flavonoid myricetin on HIV-1 infection in a dual-chamber in vitro model.

Directory of Open Access Journals (Sweden)

Silvana Pasetto

Full Text Available HIV infection by sexual transmission remains an enormous global health concern. More than 1 million new infections among women occur annually. Microbicides represent a promising prevention strategy that women can easily control. Among emerging therapies, natural small molecules such as flavonoids are an important source of new active substances. In this study we report the in vitro cytotoxicity and anti-HIV-1 and microbicide activity of the following flavonoids: Myricetin, Quercetin and Pinocembrin. Cytotoxicity tests were conducted on TZM-bl, HeLa, PBMC, and H9 cell cultures using 0.01-100 µM concentrations. Myricetin presented the lowest toxic effect, with Quercetin and Pinocembrin relatively more toxic. The anti-HIV-1 activity was tested with TZM-bl cell plus HIV-1 BaL (R5 tropic, H9 and PBMC cells plus HIV-1 MN (X4 tropic, and the dual tropic (X4R5 HIV-1 89.6. All flavonoids showed anti-HIV activity, although Myricetin was more effective than Quercetin or Pinocembrin. In TZM-bl cells, Myricetin inhibited ≥90% of HIV-1 BaL infection. The results were confirmed by quantification of HIV-1 p24 antigen in supernatant from H9 and PBMC cells following flavonoid treatment. In H9 and PBMC cells infected by HIV-1 MN and HIV-1 89.6, Myricetin showed more than 80% anti-HIV activity. Quercetin and Pinocembrin presented modest anti-HIV activity in all experiments. Myricetin activity was tested against HIV-RT and inhibited the enzyme by 49%. Microbicide activities were evaluated using a dual-chamber female genital tract model. In the in vitro microbicide activity model, Myricetin showed promising results against different strains of HIV-1 while also showing insignificant cytotoxic effects. Further studies of Myricetin should be performed to identify its molecular targets in order to provide a solid biological foundation for translational research.

LATERAL FLOW ASSAY FOR CRYPTOCOCCAL ANTIGEN: AN IMPORTANT ADVANCE TO IMPROVE THE CONTINUUM OF HIV CARE AND REDUCE CRYPTOCOCCAL MENINGITIS-RELATED MORTALITY

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Jose E. VIDAL

2015-09-01

Full Text Available SUMMARYAIDS-related cryptococcal meningitis continues to cause a substantial burden of death in low and middle income countries. The diagnostic use for detection of cryptococcal capsular polysaccharide antigen (CrAg in serum and cerebrospinal fluid by latex agglutination test (CrAg-latex or enzyme-linked immunoassay (EIA has been available for over decades. Better diagnostics in asymptomatic and symptomatic phases of cryptococcosis are key components to reduce mortality. Recently, the cryptococcal antigen lateral flow assay (CrAg LFA was included in the armamentarium for diagnosis. Unlike the other tests, the CrAg LFA is a dipstick immunochromatographic assay, in a format similar to the home pregnancy test, and requires little or no lab infrastructure. This test meets all of the World Health Organization ASSURED criteria (Affordable, Sensitive, Specific, User friendly, Rapid/robust, Equipment-free, and Delivered. CrAg LFA in serum, plasma, whole blood, or cerebrospinal fluid is useful for the diagnosis of disease caused by Cryptococcusspecies. The CrAg LFA has better analytical sensitivity for C. gattii than CrAg-latex or EIA. Prevention of cryptococcal disease is new application of CrAg LFA via screening of blood for subclinical infection in asymptomatic HIV-infected persons with CD4 counts < 100 cells/mL who are not receiving effective antiretroviral therapy. CrAg screening of leftover plasma specimens after CD4 testing can identify persons with asymptomatic infection who urgently require pre-emptive fluconazole, who will otherwise progress to symptomatic infection and/or die.

β-endorphin antigen

International Nuclear Information System (INIS)

1981-01-01

This invention relates to the production of antigens comprising β-endorphin, βsub(h)-endorphin, or βsub(c)-endorphin, in covalent conjugation with human gammaglobulin as immunogenic carrier material, and an antibody having the property of specifically binding β-endorphin or fragments thereof, containing the (6-15) residue sequence. (U.K.)

Determinants of wheat antigen and fungal alpha-amylase exposure in bakeries.

Science.gov (United States)

Burstyn, I; Teschke, K; Bartlett, K; Kennedy, S M

1998-05-01

The study's objectives were to measure flour antigen exposure in bakeries and define the determinants of exposure. Ninety-six bakery workers, employed in seven different bakeries, participated in the study. Two side-by-side full-shift inhalable dust samples were obtained from each study participant on a single occasion. The flour antigen exposure was measured as wheat antigen and fungal alpha-amylase content of the water-soluble fraction of inhalable dust, assayed via enzyme-linked immunosorbent assays. During the entire sampling period bakers were observed and information on 14 different tasks was recorded at 15-minute intervals. Other production characteristics were also recorded for each sampling day and used in statistical modeling to identify significant predictors of exposure. The mean alpha-amylase antigen exposure was 22.0 ng/m3 (ranging from below the limit of detection of 0.1 ng/m3 to 307.1 ng/m3) and the mean wheat antigen exposure was 109 micrograms/m3 (ranging from below the limit of detection of 1 microgram/m3 to 1018 micrograms/m3). Regression models that explained 74% of variability in wheat antigen and alpha-amylase antigen exposures were constructed. The models indicated that tasks such as weighing, pouring, and operating dough-brakers increased flour antigen exposure, while packing and decorating resulted in lower exposures. Croissant, puff-pastry, and bread/bun production lines were associated with increased exposure, while cake production and substitution of dusting with the use of divider oil were associated with decreased exposure. Exposure levels can be reduced by the automation of forming tasks, alteration of tasks requiring pouring of flour, and changes to the types of products manufactured.

Expanded polyfunctional T cell response to mycobacterial antigens in TB disease and contraction post-treatment.

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James M Young

2010-06-01

Full Text Available T cells producing multiple factors have been shown to be required for protection from disease progression in HIV but we have recently shown this not to be the case in TB. Subjects with active disease had a greater proportion of polyfunctional cells responding to ESAT-6/CFP-10 stimulation than their infected but non-diseased household contacts (HHC. We therefore wanted to assess this profile in subjects who had successfully completed standard TB chemotherapy.We performed a cross-sectional study using PBMC from TB cases (pre- and post-treatment and HHC. Samples were stimulated overnight with TB antigens (ESAT-6/CFP-10 and PPD and their CD4+ and CD8+ T cells were assessed for production of CD107a, IFN-gamma, IL-2 and TNF-alpha and the complexity of the responses was determined using SPICE and PESTLE software.We found that an increase in complexity (i.e., production of more than 1 factor simultaneously of the T cell profile was associated with TB disease and that this was significantly reduced following TB treatment. This implies that T cells are able to respond adequately to TB antigens with active disease (at least initially but the ability of this response to protect the host from disease progression is hampered, presumably due to immune evasion strategies by the bacteria. These findings have implications for the development of new diagnostics and vaccine strategies.

Thrombocytopenia in HIV

African Journals Online (AJOL)

2007-06-15

infected community and can severely hamper thrombopoietin production, due to liver damage. HIV and platelets. Thrombocytopenia in HIV was first described in 1982. The prevalence is more or less 40%, depending on which ...

Screening for epitope specificity directly on culture supernatants in the early phase of monoclonal antibody production by an ELISA with biotin-labeled antigen.

Science.gov (United States)

Andersen, Ditte C; Jensen, Charlotte H; Gregersen, Annemette; Brandt, Jette; Kliem, Anette; Skjødt, Karsten; Koch, Claus; Teisner, Børge

2004-01-01

This report describes an assay for comparison of epitope specificity in groups of monoclonal antibodies against a given antigen. The only prerequisite is the biotin-labeled antigen. One of the monoclonal antibodies is captured onto a plastic surface via a rabbit anti-mouse Ig, and the other preincubated with biotinylated antigen. When the two antibodies react with the same epitope subsequent binding of the biotin-labeled antigen is abolished (inhibition). In the cases where no inhibition was observed, the two antibodies were considered to react with distinct, independent epitopes. The obvious advantages using this assay, are that it can be performed directly on culture supernatants in the early phase of monoclonal antibody production, and also works for antigens with repetitive epitopes. Moreover, the bonus effect, i.e., a signal in excess of the reference signal when sets of monoclonal antibodies with different epitope specificity are compared, gives a relative measure of affinity.

Heterologous prime-boost regimens with a recombinant chimpanzee adenoviral vector and adjuvanted F4 protein elicit polyfunctional HIV-1-specific T-Cell responses in macaques.

Science.gov (United States)

Lorin, Clarisse; Vanloubbeeck, Yannick; Baudart, Sébastien; Ska, Michaël; Bayat, Babak; Brauers, Geoffroy; Clarinval, Géraldine; Donner, Marie-Noëlle; Marchand, Martine; Koutsoukos, Marguerite; Mettens, Pascal; Cohen, Joe; Voss, Gerald

2015-01-01

HIV-1-specific CD4+ and CD8+ T lymphocytes are important for HIV-1 replication control. F4/AS01 consists of F4 recombinant fusion protein (containing clade B Gag/p24, Pol/RT, Nef and Gag/p17) formulated in AS01 Adjuvant System, and was shown to induce F4-specific polyfunctional CD4+ T-cell responses in humans. While replication-incompetent recombinant HIV-1/SIV antigen-expressing human adenoviral vectors can elicit high-frequency antigen-specific CD8+ T-cell responses, their use is hampered by widespread pre-existing immunity to human serotypes. Non-human adenovirus serotypes associated with lower prevalence may offer an alternative strategy. We evaluated the immunogenicity of AdC7-GRN ('A'), a recombinant chimpanzee adenovirus type 7 vector expressing clade B Gag, RT and Nef, and F4/AS01 ('P'), when delivered intramuscularly in homologous (PP or AA) and heterologous (AAPP or PPAA) prime-boost regimens, in macaques and mice. Vaccine-induced HIV-1-antigen-specific T cells in peripheral blood (macaques), liver, spleen, and intestinal and genital mucosa (mice) were characterized by intracellular cytokine staining. Vaccine-specific IgG antibodies (macaques) were detected using ELISA. In macaques, only the heterologous prime-boost regimens induced polyfunctional, persistent and balanced CD4+ and CD8+ T-cell responses specific to each HIV-1 vaccine antigen. AdC7-GRN priming increased the polyfunctionality of F4/AS01-induced CD4+ T cells. Approximately 50% of AdC7-GRN-induced memory CD8+ T cells exhibited an effector-memory phenotype. HIV-1-specific antibodies were detected with each regimen. In mice, antigen-specific CD4+ and CD8+ T-cell responses were detected in the mucosal and systemic anatomical compartments assessed. When administered in heterologous prime-boost regimens, AdC7-GRN and F4/AS01 candidate vaccines acted complementarily in inducing potent and persistent peripheral blood HIV-1-specific CD4+ and CD8+ T-cell responses and antibodies in macaques. Besides

Illness, death, and macronutrients: adequacy of rural Mozambican household production of macronutrients in the face of HIV/AIDS.

Science.gov (United States)

Donovan, Cynthia; Massingue, Jaquelino

2007-06-01

As the public sector and civil society develop intervention programs to deal with the HIV/ AIDS epidemic, there has been an increasing emphasis on the relationship between nutrition and the disease. Drug interventions may be ineffective, and the progression from HIV infection to full-blown AIDS may be accelerated without adequate nutrition. Mozambique is still fighting an increasing prevalence rate of HIV including in rural areas. Rural households in Mozambique rely heavily on their own agricultural production for the basic macronutrients. To evaluate the extent to which household agricultural production of basic staples meets overall household needs for major macronutrients, comparing households affected and not directly affected by HIV/ AIDS and other major illnesses over two time periods. Methods. This research analyzes nationally representative panel data from rural household surveys conducted in 2002 and 2005 to evaluate whether households that have suffered the chronic illness or illness-related death of prime-age adult members (15 to 49 years of age) are more vulnerable to macronutrient gaps. Households in the South and in the North with a male illness or death in 2002 produced significantly less macronutrients from crops in 2005 than nonaffected households. These households also had significantly lower income per adult equivalent. Mortality or illness from HIV/AIDS affects the ability of agricultural households dependent on own-food production to produce macronutrients. Interventions to improve access to food may be needed for affected households, particularly in light of their inability to recover over time. More analysis is needed to understand income sources, crop diversification, and access to macronutrients through the market.

Estimating the fraction of progeny virions that must incorporate APOBEC3G for suppression of productive HIV-1 infection

International Nuclear Information System (INIS)

Thangavelu, Pulari U.; Gupta, Vipul; Dixit, Narendra M.

2014-01-01

The contest between the host factor APOBEC3G (A3G) and the HIV-1 protein Vif presents an attractive target of intervention. The extent to which the A3G–Vif interaction must be suppressed to tilt the balance in favor of A3G remains unknown. We employed stochastic simulations and mathematical modeling of the within-host dynamics and evolution of HIV-1 to estimate the fraction of progeny virions that must incorporate A3G to render productive infection unsustainable. Using three different approaches, we found consistently that a transition from sustained infection to suppression of productive infection occurred when the latter fraction exceeded ∼0.8. The transition was triggered by A3G-induced hypermutations that led to premature stop codons compromising viral production and was consistent with driving the basic reproductive number, R 0 , below unity. The fraction identified may serve as a quantitative guideline for strategies targeting the A3G–Vif axis. - Highlights: • We perform simulations and mathematical modeling of the role of APOBEC3G in suppressing HIV-1 infection. • In three distinct ways, we estimate that when over 80% of progeny virions carry APOBEC3G, productive HIV-1 infection would be suppressed. • Our estimate of this critical fraction presents quantitative guidelines for strategies targeting the APOBEC3G–Vif axis

Detection of Acute and Early HIV-1 Infections in an HIV Hyper-Endemic Area with Limited Resources.

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Simnikiwe H Mayaphi

Full Text Available Two thirds of the world's new HIV infections are in sub-Saharan Africa. Acute HIV infection (AHI is the time of virus acquisition until the appearance of HIV antibodies. Early HIV infection, which includes AHI, is the interval between virus acquisition and establishment of viral load set-point. This study aimed to detect acute and early HIV infections in a hyper-endemic setting.This was a cross-sectional diagnostic study that enrolled individuals who had negative rapid HIV results in five clinics in South Africa. Pooled nucleic acid amplification testing (NAAT was performed, followed by individual sample testing in positive pools. NAAT-positive participants were recalled to the clinics for confirmatory testing and appropriate management. HIV antibody, p24 antigen, Western Blot and avidity tests were performed for characterization of NAAT-positive samples.The study enrolled 6910 individuals with negative rapid HIV results. Median age was 27 years (interquartile range {IQR}: 23-31. NAAT was positive in 55 samples, resulting in 0.8% newly diagnosed HIV-infected individuals (95% confidence interval {CI}: 0.6-1.0. The negative predictive value for rapid HIV testing was 99.2% (95% CI: 99.0-99.4. Characterization of NAAT-positive samples revealed that 0.04% (95% CI: 0.000-0.001 had AHI, 0.3% (95% CI: 0.1-0.4 had early HIV infection, and 0.5% (95% CI: 0.5-0.7 had chronic HIV infection. Forty-seven (86% of NAAT-positive participants returned for follow-up at a median of 4 weeks (IQR: 2-8. Follow-up rapid tests were positive in 96% of these participants.NAAT demonstrated that a substantial number of HIV-infected individuals are misdiagnosed at South African points-of-care. Follow-up rapid tests done within a 4 week interval detected early and chronic HIV infections initially missed by rapid HIV testing. This may be a practical and affordable strategy for earlier detection of these infections in resource-constrained settings. Newer molecular tests that can

Isocyanate test antigens

International Nuclear Information System (INIS)

Karol, M.H.; Alarie, Y.C.

1980-01-01

A test antigen for detecting antibodies to a diisocyanate comprises the reaction product of a protein and a monoisocyanate derived from the same radical as the diisocyanate. The diisocyanates most usually encountered and therefore calling for antibody detection are those of toluene, hexamethylene, methylene, isophorone and naphthylene. The preferred protein is human serum albumin. (author)

Flazinamide, a novel β-carboline compound with anti-HIV actions

International Nuclear Information System (INIS)

Wang Yunhua; Tang Jianguo; Wang Ruirui; Yang Liumeng; Dong Zejun; Du Li; Shen Xu; Liu Jikai; Zheng Yongtang

2007-01-01

A β-carboline compound, flazin isolated from Suillus granulatus has been shown weak anti-HIV-1 activity. Based on the structure of flazin, flazinamide [1-(5'- hydromethyl-2'-furyl)-β-carboline-3-carboxamide] was synthesized and its anti-HIV activities were evaluated in the present study. The cytotoxicity of flazinamide was about 4.1-fold lower than that of flazin. Flazinamide potently reduced syncytium formation induced by HIV-1IIIB with EC50 value of 0.38 μM, the EC50 of flazinamide was about 6.2-fold lower than that of flazin. Flazinamide also inhibited HIV-2ROD and HIV-2CBL-20 infection with EC50 values of 0.57 and 0.89 μM, respectively. Flazinamide reduced p24 antigen expression in HIV-1IIIB acute infected C8166 and in clinical isolated strain HIV-1KM018 infected PBMC, with EC50 values of 1.45 and 0.77 μM, respectively. Flazinamide did not suppress HIV-1 replication in chronically infected H9 cells. Flazinamide blocked the fusion between normal cells and HIV-1 or HIV-2 chronically infected cells. It weakly inhibited activities of recombinant HIV-1 reverse transcriptase, protease or integrase at higher concentrations. In conclusion, the conversion of the carboxyl group in 3 position of flazin markedly enhanced the anti-viral activity (TI value increased from 12.1 to 312.2) and flazinamide might interfere in the early stage of HIV life cycle

RT-PCR Detection of HIV in Republic of Macedonia

Directory of Open Access Journals (Sweden)

Golubinka Bosevska

2008-11-01

Full Text Available The aim of the study was to detect HIV RNA in seropositive patients using RT-PCR method and thus, to establish PCR methodology in the routine laboratory works.The total of 33 examined persons were divided in two groups: 1 13 persons seropositive for HIV; and 2 20 healthy persons - randomly selected blood donors that made the case control group. The subjects age was between 25 and 52 years (average 38,5.ELFA test for combined detection of HIV p24 antigen and anti HIV-1 + 2 IgG and ELISA test for detection of antibodies against HIV-1 and HIV-2, were performed for each examined person. RNA from the whole blood was extracted using a commercial kit based on salt precipitation. Detection of HIV RNA was performed using RT-PCR kit. Following nested PCR, the product was separated by electrophoresis in 1,5 % agarose gel. The result was scored positive if the band of 210bp was visible regardless of intensity Measures of precaution were taken during all the steps of the work and HIV infected materials were disposed of accordingly.In the group of blood donors ELFA, ELISA and RT-PCR were negative. Assuming that prevalence of HIV infection is zero, the clinical specificity of RT-PCR is 100 %. The analytical specificity of RT-PCR method was tested against Hepatitis C and B, Human Papiloma Virus, Cytomegalovirus, Herpes Simplex Virus, Rubella Virus, Mycobacterium tuberculosis, Chlamydia trachomatis. None of these templates yielded amplicon. In the group of 13 seropositive persons, 33 samples were analyzed. HIV RNA was detected in 15 samples. ELISA and ELFA test were positive in all samples. Different aliquots of the samples were tested independently and showed the same results. After different periods of storing the RNA samples at -70°C, RT-PCR reaction was identical to the one performed initially. The obtained amplicons were maintained frozen at -20°C for a week and the subsequently performed electrophoresis was identical to the previous one. The reaction is

Cost-effectiveness of HIV screening of blood donations in Accra (Ghana)

NARCIS (Netherlands)

van Hulst, Marinus; Sagoe, Kwamena W. C.; Vermande, Jacobien E.; van der Schaaf, Ido P.; Adriani, Willem P. A. van der Tuuk; Torpey, Kwasi; Ansah, Justina; Mingle, Julius A. A.; Smit Sibinga, Cees Th.; Postma, Maarten J.

2008-01-01

Objectives: Areas with high HIV-incidence rates compared to the developed world may benefit from additional testing in blood banks and may show more favorable cost-effectiveness ratios. We evaluated the cost-effectiveness of adding p24 antigen, mini pool nucleic acid amplification testing (MP-NAT),

Low prevalence of liver disease but regional differences in HBV treatment characteristics mark HIV/HBV co-infection in a South African HIV clinical trial.

Directory of Open Access Journals (Sweden)

Prudence Ive

Full Text Available Hepatitis B virus (HBV infection is endemic in South Africa however, there is limited data on the degree of liver disease and geographic variation in HIV/HBV coinfected individuals. In this study, we analysed data from the CIPRA-SA 'Safeguard the household study' in order to assess baseline HBV characteristics in HIV/HBV co-infection participants prior to antiretroviral therapy (ART initiation.812 participants from two South African townships Soweto and Masiphumelele were enrolled in a randomized trial of ART (CIPRA-SA. Participants were tested for hepatitis B surface antigen (HBsAg, hepatitis B e antigen (HBeAg, and HBV DNA. FIB-4 scores were calculated at baseline.Forty-eight (5.9% were HBsAg positive, of whom 28 (58.3% were HBeAg positive. Of those with HBV, 29.8% had an HBV DNA<2000 IU/ml and ALT<40 IU/ml ; 83.0% had a FIB-4 score <1.45, consistent with absent or minimal liver disease. HBV prevalence was 8.5% in Masiphumelele compared to 3.8% in Soweto (relative risk 2.3; 95% CI: 1.3-4.0. More participants in Masiphumelele had HBeAg-negative disease (58% vs. 12%, p = 0.002 and HBV DNA levels ≤2000 IU/ml, (43% vs. 6% p<0.007.One third of HIV/HBV co-infected subjects had low HBV DNA levels and ALT while the majority had indicators of only mild liver disease. There were substantial regional differences in HBsAg and HbeAg prevalence in HIV/HBV co-infection between two regions in South Africa. This study highlights the absence of severe liver disease and the marked regional differences in HIV/HBV co-infection in South Africa and will inform treatment decisions in these populations.

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

candidate viral gene products with CD8 T-cell lines from 3 BHV-1-immune cattle of defined MHC genotypes identified 4 antigens, including 3 immediate early (IE) gene products (ICP4, ICP22 and Circ) and a tegument protein (UL49). Identification of the MHC restriction specificities revealed that the antigens...... cases refined, the identity of the epitopes. Analyses of the epitope specificity of the CD8 T-cell lines showed that a large component of the response is directed against these IE epitopes. The results indicate that these IE gene products are dominant targets of the CD8 T-cell response in BHV...

Skin advanced glycation end products in HIV infection are increased and predictive of development of cardiovascular events

NARCIS (Netherlands)

Sprenger, Herman G.; Bierman, Wouter F.; Martes, Melanie I.; Graaff, Reindert; van der Werf, Tjip S.; Smit, Andries J.

2017-01-01

Objective: HIV-1 infection is associated with an increased cardiovascular disease (CVD) risk. Advanced glycation end products are formed as stable markers of glycaemic and oxidative stress. Skin autofluorescence (SAF) as marker of accumulated advanced glycation end products is increased and

Accurate radioimmunoassay of human growth hormone with separation on polyacrylamide gel electrophoresis of free antigen; antigen-anti-body complex and damaged labelled antigen: a study is performed on this last one for the purpose of obtaining long lasting labelled products

International Nuclear Information System (INIS)

Bartolini, P.; Assis, L.M.; Schwarz, I.; Macchione, M.; Pieroni, R.R.

1977-01-01

The intent of this work was the obtainement of a radioimmunoassay method, accurate and precise enough, to furnish a suitable way for determining Human Growth Hormone (HGH) in extracts or in physiological fluids, useful more for specific research purposes than for routinized clinical assays, and where the labelled products could be used as long as possible. Only one technique was found that could give an answer to these requirements, though under some aspects more laborious than others: Polyacrylamide Gel Electrophoresis (PAGE). This was used introducing some modifications to the original method of Davis, and it was possible, using tubes 11 cm long, to separate on the same gel, the free, the antibody bound, and the damaged labelled antigen. The method, being able to detect separately and independently these three components and to give a better control on the analytically dangerous 'damaged', furnished accurate and reproducible curves. An example of determination is the one on KABI-Crescormon, that compares the results obatined with the present technique to those presented by another laboratory. Thanks to this method the labelled antigen could be used up to one month of time. After this period a re-purification on Sephadex was introduced so that the same labelled product was profitable for two more months. Parallel to this work a study has been performed on the various components originating in this so called process of 'damaging', and a particular importance has also been given to a more precise knowledge of the amount of antigen, in terms of mass, present in an assay. (orig.) [de

[Comparison of the clinical performance of the ECLusys HIV combi assay with the Lumipulse f and HISCL 2000-i HIV-1/2 ab screening assays].

Science.gov (United States)

Sugiura, Aya; Iwahara, Kunihiro; Suga, Yasuyuki; Uchiyama, Sachinori; Maekawa, Masato

2012-04-01

We compared the ECLusys HIV combi assay (ECL HIV Ag/Ab) to the Lumipulse Forte (LPf HIV 1/2 Ab) and HISCL (HIS HIV 1/2 Ab) assays. In a dilution sensitivity test using dilution panels of WHO HIV antibody international reference panel (HIV-1 Subtype A, B, C, E, HIV-1 Group O, HIV-2) and HIV-1/2 Ab CE marked material(HIV-1, HIV-2) parent specimens, the ECL assay enabled detection at a higher level of sensitivity than either the LPf assay or the HIS assay for all dilution panels. In an early detection test in the early phase of infection in which a BBI HIV seroconversion panel was used, the ECL assay enabled detection 7 days after initial blood sample collection, whereas the LPf and HIS assays enabled detection after 27 days. In a specificity test using high RF positive specimens (n=33), pregnancy specimens (n=35), cytomegalovirus antibody positive specimens (n=36), and high M protein positive specimens (n=21) that were confirmed negative for HIV-1/2 antibodies by the LPf assay, negative results were obtained for all specimens on both the ECL assay and the HIS assay. In a correlation test using routinely collected clinical specimens (n=121), including positive stock specimens, the ECL and HIS assays demonstrated the highest agreement rate 98.3%. The above results confirmed that the fourth-generation reagent ECL assay, which simultaneously detects both HIV-1/2 antibodies and p24 antigens, is both highly sensitive and specific, and is a suitable assay for use in routine testing.

Sequence similarity between the erythrocyte binding domain 1 of the Plasmodium vivax Duffy binding protein and the V3 loop of HIV-1 strain MN reveals binding residues for the Duffy Antigen Receptor for Chemokines

Directory of Open Access Journals (Sweden)

Garry Robert F

2011-01-01

Full Text Available Abstract Background The surface glycoprotein (SU, gp120 of the human immunodeficiency virus (HIV must bind to a chemokine receptor, CCR5 or CXCR4, to invade CD4+ cells. Plasmodium vivax uses the Duffy Binding Protein (DBP to bind the Duffy Antigen Receptor for Chemokines (DARC and invade reticulocytes. Results Variable loop 3 (V3 of HIV-1 SU and domain 1 of the Plasmodium vivax DBP share a sequence similarity. The site of amino acid sequence similarity was necessary, but not sufficient, for DARC binding and contained a consensus heparin binding site essential for DARC binding. Both HIV-1 and P. vivax can be blocked from binding to their chemokine receptors by the chemokine, RANTES and its analog AOP-RANTES. Site directed mutagenesis of the heparin binding motif in members of the DBP family, the P. knowlesi alpha, beta and gamma proteins abrogated their binding to erythrocytes. Positively charged residues within domain 1 are required for binding of P. vivax and P. knowlesi erythrocyte binding proteins. Conclusion A heparin binding site motif in members of the DBP family may form part of a conserved erythrocyte receptor binding pocket.

Presenting native-like HIV-1 envelope trimers on ferritin nanoparticles improves their immunogenicity

NARCIS (Netherlands)

Sliepen, Kwinten; Ozorowski, Gabriel; Burger, Judith A.; van Montfort, Thijs; Stunnenberg, Melissa; Labranche, Celia; Montefiori, David C.; Moore, John P.; Ward, Andrew B.; Sanders, Rogier W.

2015-01-01

Background: Presenting vaccine antigens in particulate form can improve their immunogenicity by enhancing B cell activation. Findings: We describe ferritin-based protein nanoparticles that display multiple copies of native-like HIV-1 envelope glycoprotein trimers (BG505 SOSIP.664). Trimer-bearing

Kefiran suppresses antigen-induced mast cell activation.

Science.gov (United States)

Furuno, Tadahide; Nakanishi, Mamoru

2012-01-01

Kefir is a traditional fermented milk beverage produced by kefir grains in the Caucasian countries. Kefiran produced by Lactobacillus kefiranofaciens in kefir grains is an exopolysaccharide having a repeating structure with glucose and galactose residues in the chain sequence and has been suggested to exert many health-promoting effects such as immunomodulatory, hypotensive, hypocholesterolemic activities. Here we investigated the effects of kefiran on mast cell activation induced by antigen. Pretreatment with kefiran significantly inhibited antigen-induced Ca(2+) mobilization, degranulation, and tumor necrosis factor-α production in bone marrow-derived mast cells (BMMCs) in a dose-dependent manner. The phosphorylation of Akt, glycogen synthase kinase 3β, and extracellular signal-regulated kinases (ERKs) after antigen stimulation was also suppressed by pretreatment of BMMCs with kefiran. These findings indicate that kefiran suppresses mast cell degranulation and cytokine production by inhibiting the Akt and ERKs pathways, suggesting an anti-inflammatory effect for kefiran.

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.

Prevalence of hepatitis C and B virus among patients infected with HIV: a cross-sectional analysis of a large HIV care programme in Myanmar.

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Zaw, Sai Ko Ko; Tun, Sai Thein Than; Thida, Aye; Aung, Thet Ko; Maung, Win; Shwe, Myint; Aye, Mar Mar; Clevenbergh, Phillipe

2013-07-01

Co-infection with the hepatitis C virus (HCV) and/or hepatitis B virus (HBV) influences the morbidity and mortality of patients with HIV. A cross sectional analysis was of 11,032 HIV-infected patients enrolled in the Integrated HIV Care Program from May 2005 to April 2012 and Epi-info 3.5 was used to determine the serological prevalence of chronic hepatitis B and hepatitis C. The mean ± standard deviation age of patients was 36 ± 8.4 years (adult cohort) and 7 ± 3 years (paediatric cohort). The sero prevalence of hepatitis B surface antigen, hepatitis C (anti HCV antibodies) and triple infection are 8.7%, 5.3% and 0.35%, respectively. Men who have sex with men are at the highest risk of being co-infected with hepatitis B while intravenous drug users are at the highest risk of being co-infected with hepatitis C. It is important to screen for hepatitis B and C in HIV infected people in order to provide quality care for HIV patients with co-infection.

Antigen-presenting cells represent targets for R5 HIV-1 infection in the first trimester pregnancy uterine mucosa.

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Romain Marlin

Full Text Available BACKGROUND: During the first trimester of pregnancy, HIV-1 mother-to-child transmission is relatively rare despite the permissivity of placental cells to cell-to-cell HIV-1 infection. The placenta interacts directly with maternal uterine cells (decidual cells but the physiological role of the decidua in the control of HIV-1 transmission and whether decidua could be a source of infected cells is unknown. METHODOLOGY/PRINCIPAL FINDINGS: To answer to this question, decidual mononuclear cells were exposed to HIV-1 in vitro. Decidual cells were shown to be more susceptible to infection by an R5 HIV-1, as compared to an X4 HIV-1. Infected cells were identified by flow cytometry analysis. The results showed that CD14(+ cells were the main targets of HIV-1 infection in the decidua. These infected CD14(+ cells expressed DC-SIGN, CD11b, CD11c, the Fc gamma receptor CD16, CD32 and CD64, classical MHC class-I and class-II and maturation and activation molecules CD83, CD80 and CD86. The permissivity of decidual tissue was also evaluated by histoculture. Decidual tissue was not infected by X4 HIV-1 but was permissive to R5 HIV-1. Different profiles of infection were observed depending on tissue localization. CONCLUSIONS/SIGNIFICANCE: The presence of HIV-1 target cells in the decidua in vitro and the low rate of in utero mother-to-child transmission during the first trimester of pregnancy suggest that a natural control occurs in vivo limiting cell-to-cell infection of the placenta and consequently infection of the fetus.

Basic Research in HIV vaccinology is hampered by reductionist thinking

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Marc H V Van Regenmortel

2012-07-01

Full Text Available This review describes the structure-based reverse vaccinology approach aimed at developing vaccine immunogens capable of inducing antibodies that broadly neutralize HIV-1. Some basic principles of protein immunochemistry are reviewed and the implications of the extensive polyspecificity of antibodies for vaccine development are underlined. Although it is natural for investigators to want to know the cause of an effective immunological intervention, the classic notion of causality is shown to have little explanatory value for a system as complex as the immune system, where any observed effect always results from many interactions between a large number of components. Causal explanations are reductive because a single factor is singled out for attention and given undue explanatory weight on its own. Other examples of the negative impact of reductionist thinking on HIV vaccine development are discussed. These include 1 the failure to distinguish between the chemical nature of antigenicity and the biological nature of immunogenicity, 2 the belief that when an HIV-1 epitope is reconstructed by rational design to better fit a neutralizing Mab, this will produce an immunogen able to elicit Abs with the same neutralizing capacity as the Ab used as template for designing the antigen 3 the belief that protection against infection can be analysed at the level of individual molecular interactions although it has meaning only at the level of an entire organism.The numerous unsuccessful strategies that have been used to design HIV-1 vaccine immunogens are described and it is suggested that the convergence of so many negative experimental results, justifies the conclusion that reverse vaccinology is unlikely to lead to the development of a preventive HIV-1 vaccine. Immune correlates of protection in vaccinees have not yet been identified because this will become feasible only retrospectively once an effective vaccine exists.

Hepatitis B and C Co-Infection in HIV Patients from the TREAT Asia HIV Observational Database: Analysis of Risk Factors and Survival

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Chen, Marcelo; Wong, Wing-Wai; Law, Matthew G.; Kiertiburanakul, Sasisopin; Yunihastuti, Evy; Merati, Tuti Parwati; Lim, Poh Lian; Chaiwarith, Romanee; Phanuphak, Praphan; Lee, Man Po; Kumarasamy, Nagalingeswaran; Saphonn, Vonthanak; Ditangco, Rossana; Sim, Benedict L. H.; Nguyen, Kinh Van; Pujari, Sanjay; Kamarulzaman, Adeeba; Zhang, Fujie; Pham, Thuy Thanh; Choi, Jun Yong; Oka, Shinichi; Kantipong, Pacharee; Mustafa, Mahiran; Ratanasuwan, Winai; Durier, Nicolas; Chen, Yi-Ming Arthur

2016-01-01

Background We assessed the effects of hepatitis B (HBV) or hepatitis C (HCV) co-infection on outcomes of antiretroviral therapy (ART) in HIV-infected patients enrolled in the TREAT Asia HIV Observational Database (TAHOD), a multi-center cohort of HIV-infected patients in the Asia-Pacific region. Methods Patients testing HBs antigen (Ag) or HCV antibody (Ab) positive within enrollment into TAHOD were considered HBV or HCV co-infected. Factors associated with HBV and/or HCV co-infection were assessed by logistic regression models. Factors associated with post-ART HIV immunological response (CD4 change after six months) and virological response (HIV RNA <400 copies/ml after 12 months) were also determined. Survival was assessed by the Kaplan-Meier method and log rank test. Results A total of 7,455 subjects were recruited by December 2012. Of patients tested, 591/5656 (10.4%) were HBsAg positive, 794/5215 (15.2%) were HCVAb positive, and 88/4966 (1.8%) were positive for both markers. In multivariate analysis, HCV co-infection, age, route of HIV infection, baseline CD4 count, baseline HIV RNA, and HIV-1 subtype were associated with immunological recovery. Age, route of HIV infection, baseline CD4 count, baseline HIV RNA, ART regimen, prior ART and HIV-1 subtype, but not HBV or HCV co-infection, affected HIV RNA suppression. Risk factors affecting mortality included HCV co-infection, age, CDC stage, baseline CD4 count, baseline HIV RNA and prior mono/dual ART. Shortest survival was seen in subjects who were both HBV- and HCV-positive. Conclusion In this Asian cohort of HIV-infected patients, HCV co-infection, but not HBV co-infection, was associated with lower CD4 cell recovery after ART and increased mortality. PMID:26933963

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

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

1992-01-01

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......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...... response, compared with only 1 (3%) of 31 patients without PCP (P less than .001). This patient had PCP on the basis of clinical criteria, including response to therapy. Thus, despite severe immunosuppression, a proportion of HIV-infected patients with PCP can mount a specific IgG-mediated antibody...

Expression of Human CD4 and chemokine receptors in cotton rat cells confers permissiveness for productive HIV infection

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Broder Christopher C

2009-05-01

Full Text Available Abstract Background Current small animal models for studying HIV-1 infection are very limited, and this continues to be a major obstacle for studying HIV-1 infection and pathogenesis, as well as for the urgent development and evaluation of effective anti-HIV-1 therapies and vaccines. Previously, it was shown that HIV-1 can infect cotton rats as indicated by development of antibodies against all major proteins of the virus, the detection of viral cDNA in spleen and brain of challenged animals, the transmission of infectious virus, albeit with low efficiency, from animal to animal by blood, and an additional increase in the mortality in the infected groups. Results Using in vitro experiments, we now show that cotton rat cell lines engineered to express human receptor complexes for HIV-1 (hCD4 along with hCXCR4 or hCCR5 support virus entry, viral cDNA integration, and the production of infectious virus. Conclusion These results further suggest that the development of transgenic cotton rats expressing human HIV-1 receptors may prove to be useful small animal model for HIV infection.

Natural Mutations in Streptococcus agalactiae Resulting in Abrogation of β Antigen Production.

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Vasilyeva, Anastasia; Santos Sanches, Ilda; Florindo, Carlos; Dmitriev, Alexander

2015-01-01

Streptococcus agalactiae genome encodes 21 two-component systems (TCS) and a variety of regulatory proteins in order to control gene expression. One of the TCS, BgrRS, comprising the BgrR DNA-binding regulatory protein and BgrS sensor histidine kinase, was discovered within a putative virulence island. BgrRS influences cell metabolism and positively control the expression of bac gene, coding for β antigen at transcriptional level. Inactivation of bgrR abrogated bac gene expression and increased virulence properties of S. agalactiae. In this study, a total of 140 strains were screened for the presence of bac gene, and the TCS bgrR and bgrS genes. A total of 53 strains carried the bac, bgrR and bgrS genes. Most of them (48 strains) expressed β antigen, while five strains did not express β antigen. Three strains, in which bac gene sequence was intact, while bgrR and/or bgrS genes had mutations, and expression of β antigen was absent, were complemented with a constructed plasmid pBgrRS(P) encoding functionally active bgrR and bgrS gene alleles. This procedure restored expression of β antigen indicating the crucial regulatory role of TCS BgrRS. The complemented strain A49V/BgrRS demonstrated attenuated virulence in intraperitoneal mice model of S. agalactiae infection compared to parental strain A49V. In conclusion we showed that disruption of β antigen expression is associated with: i) insertion of ISSa4 upstream the bac gene just after the ribosomal binding site; ii) point mutation G342A resulting a stop codon TGA within the bac gene and a truncated form of β antigen; iii) single deletion (G) in position 439 of the bgrR gene resulting in a frameshift and the loss of DNA-binding domain of the BgrR protein, and iv) single base substitutions in bgrR and bgrS genes causing single amino acid substitutions in BgrR (Arg187Lys) and BgrS (Arg252Gln). The fact that BgrRS negatively controls virulent properties of S. agalactiae gives a novel clue for understanding of S

Immunization with PIII, a fraction of Schistosoma mansoni soluble adult worm antigenic preparation, affects nitric oxide production by murine spleen cells

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Diana Magalhães de Oliveira

1998-01-01

Full Text Available Nitric oxide (NO is an important effector molecule involved in immune regulation and defense. NO produced by cytokine-activated macrophages was reported to be cytotoxic against the helminth Schistosoma mansoni. Identification and characterization of S. mansoni antigens that can provide protective immunity is crucial for understanding the complex immunoregulatory events that modulate the immune response in schistosomiasis. It is, then, essential to have available defined, purified parasite antigens. Previous work by our laboratory identified a fraction of S. mansoni soluble adult worm antigenic preparation (SWAP, named PIII, able to elicit significant in vitro cell proliferation and at the same time lower in vitro and in vivo granuloma formation when compared either to SEA (soluble egg antigen or to SWAP. In the present work we report the effect of different in vivo trials with mice on their spleen cells ability to produce NO. We demonstrate that PIII-immunization is able to significantly increase NO production by spleen cells after in vitro stimulation with LPS. These data suggest a possible role for NO on the protective immunity induced by PIII.

The role of latency reversal agents in the cure of HIV: A review of current data.

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Bashiri, Kiandokht; Rezaei, Nima; Nasi, Milena; Cossarizza, Andrea

2018-04-01

The definitive cure for human immunodeficiency virus type-1 (HIV) infection is represented by the eradication of the virus from the patient's body. To reach this result, cells that are infected but do not produce the virus must become recognizable to be killed by the immune system. For this purpose, drugs defined "latency reverting agents" (LRA) that reactivate viral production are under investigation. A few clinical studies have been performed in HIV-infected patients treated with LRA and combined antiretroviral therapy (cART). The strategy is thus to combine cART and LRA to reactivate the virus and unmask latently infected cells that, because of cART, cannot produce a fully competent form of the virus. Unmasked cells can present viral antigens to the immune system, that ultimately recognizes and kills such latently infected cells. This review reports and discusses recent studies that have been published on this topic. Copyright © 2018 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

Immunization with Clinical HIV-1 Env Proteins Induces Broad Antibody Dependent Cellular Cytotoxicity-Mediating Antibodies in a Rabbit Vaccination Model.

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Karlsson, Ingrid; Borggren, Marie; Jensen, Sanne Skov; Heyndrickx, Leo; Stewart-Jones, Guillaume; Scarlatti, Gabriella; Fomsgaard, Anders

2017-11-17

The induction of both neutralizing antibodies and non-neutralizing antibodies with effector functions, for example, antibody-dependent cellular cytotoxicity (ADCC), is desired in the search for effective vaccines against HIV-1. In the pursuit of novel immunogens capable of inducing an efficient antibody response, rabbits were immunized with selected antigens using different prime-boost strategies. We immunized 35 different groups of rabbits with Env antigens from clinical HIV-1 subtypes A and B, including immunization with DNA alone, protein alone, and DNA prime with protein boost. The rabbit sera were screened for ADCC activity using a GranToxiLux-based assay with human peripheral blood mononuclear cells as effector cells and CEM.NKR CCR5 cells coated with HIV-1 envelope as target cells. The groups with the highest ADCC activity were further characterized for cross-reactivity between HIV-1 subtypes. The immunogen inducing the most potent and broadest ADCC response was a trimeric gp140. The ADCC activity was highest against the HIV-1 subtype corresponding to the immunogen. The ADCC activity did not necessarily reflect neutralizing activity in the pseudovirus-TZMbl assay, but there was an overall correlation between the two antiviral activities. We present a rabbit vaccination model and an assay suitable for screening HIV-1 vaccine candidates for the induction of ADCC-mediating antibodies in addition to neutralizing antibodies. The antigens and/or immunization strategies capable of inducing antibodies with ADCC activity did not necessarily induce neutralizing activity and vice versa. Nevertheless, we identified vaccine candidates that were able to concurrently induce both types of responses and that had ADCC activity that was cross-reactive between different subtypes. When searching for an effective vaccine candidate, it is important to evaluate the antibody response using a model and an assay measuring the desired function.

Performance-enhancing drugs: design and production of redirected chimeric antigen receptor (CAR) T cells.

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Levine, B L

2015-03-01

Performance enhancement of the immune system can now be generated through ex vivo gene modification of T cells in order to redirect native specificity to target tumor antigens. This approach combines the specificity of antibody therapy, the expanded response of cellular therapy and the memory activity of vaccine therapy. Recent clinical trials of chimeric antigen receptor (CAR) T cells directed toward CD19 as a stand-alone therapy have shown sustained complete responses in patients with acute lymphoblastic leukemia and chronic lymphocytic leukemia. As these drug products are individually derived from a patient's own cells, a different manufacturing approach is required for this kind of personalized therapy compared with conventional drugs. Key steps in the CAR T-cell manufacturing process include the selection and activation of isolated T cells, transduction of T cells to express CARs, ex vivo expansion of modified T cells and cryopreservation in infusible media. In this review, the steps involved in isolating, genetically modifying and scaling-out the CAR T cells for use in a clinical setting are described in the context of in-process and release testing and regulatory standards.

Human embryonic stem cell (hES derived dendritic cells are functionally normal and are susceptible to HIV-1 infection

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Bandi Sriram

2008-01-01

Full Text Available Abstract Background Human embryonic stem (hES cells hold considerable promise for cell replacement and gene therapies. Their remarkable properties of pluripotency, self-renewal, and tractability for genetic modification potentially allows for the production of sizeable quantities of therapeutic cells of the hematopoietic lineage. Dendritic cells (DC arise from CD34+ hematopoietic progenitor cells (HPCs and are important in many innate and adaptive immune functions. With respect to HIV-1 infection, DCs play an important role in the efficient capture and transfer of the virus to susceptible cells. With an aim of generating DCs from a renewable source for HIV-1 studies, here we evaluated the capacity of hES cell derived CD34+ cells to give rise to DCs which can support HIV-1 infection. Results Undifferentiated hES cells were cultured on S17 mouse bone marrow stromal cell layers to derive CD34+ HPCs which were subsequently grown in specific cytokine differentiation media to promote the development of DCs. The hES derived DCs (hES-DC were subjected to phenotypic and functional analyses and compared with DCs derived from fetal liver CD34+ HPC (FL-DC. The mature hES-DCs displayed typical DC morphology consisting of veiled stellate cells. The hES-DCs also displayed characteristic phenotypic surface markers CD1a, HLA-DR, B7.1, B7.2, and DC-SIGN. The hES-DCs were found to be capable of antigen uptake and stimulating naïve allogeneic CD4+ T cells in a mixed leukocyte reaction assay. Furthermore, the hES-DCs supported productive HIV-1 viral infection akin to standard DCs. Conclusion Phenotypically normal and functionally competent DCs that support HIV-1 infection can be derived from hES cells. hES-DCs can now be exploited in applied immunology and HIV-1 infection studies. Using gene therapy approaches, it is now possible to generate HIV-1 resistant DCs from anti-HIV gene transduced hES-CD34+ hematopoietic progenitor cells.

The chicken erythrocyte-specific MHC antigen. Characterization and purification of the B-G antigen by monoclonal antibodies

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Salomonsen, J; Skjødt, K; Crone, M

1987-01-01

and affinity-purified once more. Finally, reverse-phase chromatography resulted in a pure product. The B-G antigen was identified in the various fractions by rocket immunoelectrophoresis. The final product was more than 99% pure, as estimated by SDS-PAGE analysis followed by silver stain of proteins. The yield...

Motivations and barriers to uptake and use of female-initiated, biomedical HIV prevention products in sub-Saharan Africa: an adapted meta-ethnography.

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Eakle, Robyn; Bourne, Adam; Jarrett, Caitlin; Stadler, Jonathan; Larson, Heidi

2017-12-19

Women bear a disproportionate burden of HIV throughout the world prompting extensive research into HIV prevention products for women which has met with varied success. With an aim of informing future policy and programming, this review examines the barriers and motivations to the uptake and use of female initiated products in sub-Saharan countries. We conducted a systematic review as an adapted meta-ethnography of qualitative data focused on actual use of products. After deduplication, 10,581 and 3861 papers in the first and second round respectively were screened. Following the PRISMA guidance, 22 papers were selected and synthesized using Malpass's definitions of first, second, and third order constructs. First order constructs, consisting of participant data published in the selected papers, were extracted and categorised by second and third order constructs for analysis. A weight of evidence review was conducted to compare and assess quality across the papers. The 22 papers selected span 11 studies in 13 countries. We derived 23 s order constructs that were translated into seven overarching third order constructs: Sexual Satisfaction, Trust, Empowerment and Control, Personal Well-being, Product use in the social-cultural environment, Practical Considerations, Risk Reduction, and Perceptions of Efficacy. Relationships and trust were seen to be as or more important for product use as efficacy. These constructs reveal an inherent inter-relationality where decision making around HIV prevention uptake and use cannot be binary or mono-faceted, but rather conducted on multiple levels. We developed a framework illustrating the central and proximal natures of constructs as they relate to the decision-making process surrounding the use of prevention products. Health systems, structural, and individual level HIV prevention interventions for women should adopt a holistic approach. Interventions should attend to the ways in which HIV prevention products can serve to reduce

Spleen vagal denervation inhibits the production of antibodies to circulating antigens.

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Ruud M Buijs

Full Text Available BACKGROUND: Recently the vagal output of the central nervous system has been shown to suppress the innate immune defense to pathogens. Here we investigated by anatomical and physiological techniques the communication of the brain with the spleen and provided evidence that the brain has the capacity to stimulate the production of antigen specific antibodies by its parasympathetic autonomic output. METHODOLOGY/PRINCIPAL FINDINGS: This conclusion was reached by successively demonstrating that: 1. The spleen receives not only sympathetic input but also parasympathetic input. 2. Intravenous trinitrophenyl-ovalbumin (TNP-OVA does not activate the brain and does not induce an immune response. 3. Intravenous TNP-OVA with an inducer of inflammation; lipopolysaccharide (LPS, activates the brain and induces TNP-specific IgM. 4. LPS activated neurons are in the same areas of the brain as those that provide parasympathetic autonomic information to the spleen, suggesting a feed back circuit between brain and immune system. Consequently we investigated the interaction of the brain with the spleen and observed that specific parasympathetic denervation but not sympathetic denervation of the spleen eliminates the LPS-induced antibody response to TNP-OVA. CONCLUSIONS/SIGNIFICANCE: These findings not only show that the brain can stimulate antibody production by its autonomic output, it also suggests that the power of LPS as adjuvant to stimulate antibody production may also depend on its capacity to activate the brain. The role of the autonomic nervous system in the stimulation of the adaptive immune response may explain why mood and sleep have an influence on antibody production.

HIV Incidence Estimates Using the Limiting Antigen Avidity EIA Assay at Testing Sites in Kiev City, Ukraine: 2013-2014.

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Ruth Simmons

Full Text Available To estimate HIV incidence and highlight the characteristics of persons at greatest risk of HIV in the Ukraine capital, Kiev.Residual samples from newly-diagnosed persons attending the Kiev City AIDS Centre were tested for evidence of recent HIV infection using an avidity assay. Questions on possible risk factors for HIV acquisition and testing history were introduced. All persons (≥16yrs presenting for an HIV test April'13-March'14 were included. Rates per 100,000 population were calculated using region-specific denominators.During the study period 6370 individuals tested for HIV. Of the 467 individuals newly-diagnosed with HIV, 21 had insufficient samples for LAg testing. Of the remaining 446, 39 (8.7% were classified as recent with an avidity index <1.5ODn, 10 were reclassified as long-standing as their viral load was <1000 copies/mL, resulting in 29 (6.5% recent HIV infections. The only independent predictor for a recent infection was probable route of exposure, with MSM more likely to present with a recent infection compared with heterosexual contact [Odds Ratio 8.86; 95%CI 2.65-29.60]. We estimated HIV incidence at 21.5 per 100,000 population, corresponding to 466 new infections. Using population estimates for MSM and PWID, incidence was estimated to be between 2289.6 and 6868.7/100,000 MSM, and 350.4 for PWID.A high proportion of persons newly-infected remain undiagnosed, with MSM disproportionally affected with one in four newly-HIV-diagnosed and one in three recently-HIV-infected. Our findings should be used for targeted public health interventions and health promotion.

HIV Incidence Estimates Using the Limiting Antigen Avidity EIA Assay at Testing Sites in Kiev City, Ukraine: 2013-2014.

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Simmons, Ruth; Malyuta, Ruslan; Chentsova, Nelli; Karnets, Iryna; Murphy, Gary; Medoeva, Antonia; Kruglov, Yuri; Yurchenko, Alexander; Copas, Andrew; Porter, Kholoud

2016-01-01

To estimate HIV incidence and highlight the characteristics of persons at greatest risk of HIV in the Ukraine capital, Kiev. Residual samples from newly-diagnosed persons attending the Kiev City AIDS Centre were tested for evidence of recent HIV infection using an avidity assay. Questions on possible risk factors for HIV acquisition and testing history were introduced. All persons (≥16yrs) presenting for an HIV test April'13-March'14 were included. Rates per 100,000 population were calculated using region-specific denominators. During the study period 6370 individuals tested for HIV. Of the 467 individuals newly-diagnosed with HIV, 21 had insufficient samples for LAg testing. Of the remaining 446, 39 (8.7%) were classified as recent with an avidity index <1.5ODn, 10 were reclassified as long-standing as their viral load was <1000 copies/mL, resulting in 29 (6.5%) recent HIV infections. The only independent predictor for a recent infection was probable route of exposure, with MSM more likely to present with a recent infection compared with heterosexual contact [Odds Ratio 8.86; 95%CI 2.65-29.60]. We estimated HIV incidence at 21.5 per 100,000 population, corresponding to 466 new infections. Using population estimates for MSM and PWID, incidence was estimated to be between 2289.6 and 6868.7/100,000 MSM, and 350.4 for PWID. A high proportion of persons newly-infected remain undiagnosed, with MSM disproportionally affected with one in four newly-HIV-diagnosed and one in three recently-HIV-infected. Our findings should be used for targeted public health interventions and health promotion.

HIV Incidence Estimates Using the Limiting Antigen Avidity EIA Assay at Testing Sites in Kiev City, Ukraine: 2013-2014

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Kruglov, Yuri; Yurchenko, Alexander

2016-01-01

Objective To estimate HIV incidence and highlight the characteristics of persons at greatest risk of HIV in the Ukraine capital, Kiev. Method Residual samples from newly-diagnosed persons attending the Kiev City AIDS Centre were tested for evidence of recent HIV infection using an avidity assay. Questions on possible risk factors for HIV acquisition and testing history were introduced. All persons (≥16yrs) presenting for an HIV test April’13–March’14 were included. Rates per 100,000 population were calculated using region-specific denominators. Results During the study period 6370 individuals tested for HIV. Of the 467 individuals newly-diagnosed with HIV, 21 had insufficient samples for LAg testing. Of the remaining 446, 39 (8.7%) were classified as recent with an avidity index <1.5ODn, 10 were reclassified as long-standing as their viral load was <1000 copies/mL, resulting in 29 (6.5%) recent HIV infections. The only independent predictor for a recent infection was probable route of exposure, with MSM more likely to present with a recent infection compared with heterosexual contact [Odds Ratio 8.86; 95%CI 2.65–29.60]. We estimated HIV incidence at 21.5 per 100,000 population, corresponding to 466 new infections. Using population estimates for MSM and PWID, incidence was estimated to be between 2289.6 and 6868.7/100,000 MSM, and 350.4 for PWID. Conclusion A high proportion of persons newly-infected remain undiagnosed, with MSM disproportionally affected with one in four newly-HIV-diagnosed and one in three recently-HIV-infected. Our findings should be used for targeted public health interventions and health promotion. PMID:27276170

A serological study of cysticercosis in patients with HIV Estudo sorológico da cisticercose em pacientes com HIV

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Subhash Chandra Parija

2009-08-01

Full Text Available Neurocysticercosis (NCC has attained the importance of one of the most common cause of focal brain lesions in patients infected with HIV (human immunodeficiency virus. Adequate data regarding the rate of this co-infection is lacking. Therefore, the present study was carried out to determine the prevalence of cysticercosis among HIV patients residing in Puducherry or its neighboring districts of Tamil Nadu State, India. A total of one hundred blood samples were collected from HIV seropositive cases visiting JIPMER hospital, Puducherry, between June 2007 and May 2008. Enzyme immunotransfer blot (EITB and enzyme linked immunosorbent assay (ELISA were used to demonstrate anti- T. solium larval stage antibodies and Co-agglutination (Co-A test was used to detect T. solium larval stage antigens in sera. Two HIV seropositive cases were found positive for anti-T. solium larval stage antibody by EITB and four were positive by ELISA. Only one sample was positive by both EITB and ELISA. No serum sample was found positive for T. solium larval stage antigen by Co-A test. The overall seropositivity detected by all the methods was 5% in this study group. The accurate clinical diagnosis of NCC in HIV is difficult due to deranged immunological parameters in the HIV infected patients. The results of this study provides important data on the prevalence of cysticercosis in HIV positive patients in Puducherry and neighboring areas which was previously unknown. This study will also increase awareness among physicians and public health agencies about T. solium cysticercosis in the selected group.Neurocisticercose (NCC tem alcançado a importância de uma das mais comuns causas de lesões focais no cérebro em pacientes infectados pelo HIV (vírus da imunodeficiência adquirida. Dados adequados relativos à frequencia desta co-infecção estão faltando. Portanto, o presente estudo foi realizado para determinar a prevalência da cisticercose entre pacientes com HIV

Particle-based vaccines for HIV-1 infection.

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Young, Kelly R; Ross, Ted M

2003-06-01

The use of live-attenuated viruses as vaccines has been successful for the control of viral infections. However, the development of an effective vaccine against the human immunodeficiency virus (HIV) has proven to be a challenge. HIV infects cells of the immune system and results in a severe immunodeficiency. In addition, the ability of the virus to adapt to immune pressure and the ability to reside in an integrated form in host cells present hurdles for vaccinologists to overcome. A particle-based vaccine strategy has promise for eliciting high titer, long-lived, immune responses to a diverse number of viral epitopes from different HIV antigens. Live-attenuated viruses are effective at generating both cellular and humoral immunity, however, a live-attenuated vaccine for HIV is problematic. The possibility of a live-attenuated vaccine to revert to a pathogenic form or recombine with a wild-type or defective virus in an infected individual is a drawback to this approach. Therefore, these vaccines are currently only being tested in non-human primate models. Live-attenuated vaccines are effective in stimulating immunity, however challenged animals rarely clear viral infection and the degree of attenuation directly correlates with the protection of animals from disease. Another particle-based vaccine approach for HIV involves the use of virus-like particles (VLPs). VLPs mimic the viral particle without causing an immunodeficiency disease. HIV-like particles (HIV-LP) are defined as self-assembling, non-replicating, nonpathogenic, genomeless particles that are similar in size and conformation to intact virions. A variety of VLPs for both HIV and SIV are currently in pre-clinical and clinical trials. This review focuses on the current knowledge regarding the immunogenicity and safety of particle-based vaccine strategies for HIV-1.

How do HIV and AIDS impact the use of natural resources by poor rural populations? The case of wild animal products

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Charles M. Shackleton

2012-01-01

Full Text Available As a result of heightened financial and food insecurity, populations adversely affected by HIV and/or AIDS may be more likely to utilise wild natural resources to supplement their diet and livelihoods. Should this effect be pronounced, HIV and AIDS may pose a serious environmental threat. We explored the hypothesis that the presence of factors in the household, such as chronic illness in and recent mortality of individuals in a high HIV-risk age group, as well as the fostering of orphans, are associated with increased utilisation of wild animal products (WAPs at the household level. We randomly surveyed 519 households from four sites in rural South Africa, recording household socio-economic status, the utilisation of wild animal products and health and demographic factors attributed to HIV or AIDS. Binary logistic regressions were used to test if households with markers of HIV and/or AIDS affliction were more likely to have a higher incidence and frequency of WAP utilisation relative to non-afflicted households, after adjusting for socio-economic and demographic variables. We found that, although households with markers of HIV and/or AIDS were generally poorer and had higher dependency ratios, there was no evidence to support the hypothesis that WAP harvesting was associated with either poverty, or markers of HIV and/or AIDS affliction. Our findings suggest that generalisations about a possible interaction between HIV and/or AIDS and the environment may not uniformly apply to all categories of natural resources or to all user groups.

HIV-1 intersection with CD4 T cell vesicle exocytosis: intercellular communication goes viral

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Helena eSoares

2014-09-01

Full Text Available In cells of the immune system the secretion of extracellular vesicles is modulated through cellular activation. In particular, T cell activation is achieved through cell-cell contacts with antigen presenting cells and the consequent formation of a specialized signaling junction called the immunological synapse. Recent works on CD4 T cells have elucidated that cognate antigen recognition by the T cell receptor (TCR engages two distinct exocytic events. The first, involves the exocytic targeting of signaling molecules at the synaptic membrane and drives the functional architecture of the immunological synapse. The second, enlists the extracellular secretion of the TCR itself, once the functional architecture of the immunological synapse is accomplished. HIV-1, a human lymphotropic virus, has evolved sophisticated mechanisms to co-opt CD4 T cell physiology. Notably, it has become apparent that HIV-1 intersects the regulated secretory system of CD4 T cells in order to bud from the plasma membrane of the infected cell and to promote bystander cell death. Here, I review the relevance of CD4 vesicle exocytosis to immune regulation and to HIV-1 pathogenesis and discuss their potential therapeutic applications.

Altered Memory T-Cell Responses to Bacillus Calmette-Guerin and Tetanus Toxoid Vaccination and Altered Cytokine Responses to Polyclonal Stimulation in HIV-Exposed Uninfected Kenyan Infants.

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Garcia-Knight, Miguel A; Nduati, Eunice; Hassan, Amin S; Gambo, Faith; Odera, Dennis; Etyang, Timothy J; Hajj, Nassim J; Berkley, James Alexander; Urban, Britta C; Rowland-Jones, Sarah L

2015-01-01

Implementation of successful prevention of mother-to-child transmission of HIV strategies has resulted in an increased population of HIV-exposed uninfected (HEU) infants. HEU infants have higher rates of morbidity and mortality than HIV-unexposed (HU) infants. Numerous factors may contribute to poor health in HEU infants including immunological alterations. The present study assessed T-cell phenotype and function in HEU infants with a focus on memory Th1 responses to vaccination. We compared cross-sectionally selected parameters at 3 and 12 months of age in HIV-exposed (n = 42) and HU (n = 28) Kenyan infants. We measured ex vivo activated and bulk memory CD4 and CD8 T-cells and regulatory T-cells by flow cytometry. In addition, we measured the magnitude, quality and memory phenotype of antigen-specific T-cell responses to Bacillus Calmette-Guerin and Tetanus Toxoid vaccine antigens, and the magnitude and quality of the T cell response following polyclonal stimulation with staphylococcal enterotoxin B. Finally, the influence of maternal disease markers on the immunological parameters measured was assessed in HEU infants. Few perturbations were detected in ex vivo T-cell subsets, though amongst HEU infants maternal HIV viral load positively correlated with CD8 T cell immune activation at 12 months. Conversely, we observed age-dependent differences in the magnitude and polyfunctionality of IL-2 and TNF-α responses to vaccine antigens particularly in Th1 cells. These changes mirrored those seen following polyclonal stimulation, where at 3 months, cytokine responses were higher in HEU infants compared to HU infants, and at 12 months, HEU infant cytokine responses were consistently lower than those seen in HU infants. Finally, reduced effector memory Th1 responses to vaccine antigens were observed in HEU infants at 3 and 12 months and higher central memory Th1 responses to M. tuberculosis antigens were observed at 3 months only. Long-term monitoring of vaccine efficacy

Altered Memory T-Cell Responses to Bacillus Calmette-Guerin and Tetanus Toxoid Vaccination and Altered Cytokine Responses to Polyclonal Stimulation in HIV-Exposed Uninfected Kenyan Infants.

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Miguel A Garcia-Knight

Full Text Available Implementation of successful prevention of mother-to-child transmission of HIV strategies has resulted in an increased population of HIV-exposed uninfected (HEU infants. HEU infants have higher rates of morbidity and mortality than HIV-unexposed (HU infants. Numerous factors may contribute to poor health in HEU infants including immunological alterations. The present study assessed T-cell phenotype and function in HEU infants with a focus on memory Th1 responses to vaccination. We compared cross-sectionally selected parameters at 3 and 12 months of age in HIV-exposed (n = 42 and HU (n = 28 Kenyan infants. We measured ex vivo activated and bulk memory CD4 and CD8 T-cells and regulatory T-cells by flow cytometry. In addition, we measured the magnitude, quality and memory phenotype of antigen-specific T-cell responses to Bacillus Calmette-Guerin and Tetanus Toxoid vaccine antigens, and the magnitude and quality of the T cell response following polyclonal stimulation with staphylococcal enterotoxin B. Finally, the influence of maternal disease markers on the immunological parameters measured was assessed in HEU infants. Few perturbations were detected in ex vivo T-cell subsets, though amongst HEU infants maternal HIV viral load positively correlated with CD8 T cell immune activation at 12 months. Conversely, we observed age-dependent differences in the magnitude and polyfunctionality of IL-2 and TNF-α responses to vaccine antigens particularly in Th1 cells. These changes mirrored those seen following polyclonal stimulation, where at 3 months, cytokine responses were higher in HEU infants compared to HU infants, and at 12 months, HEU infant cytokine responses were consistently lower than those seen in HU infants. Finally, reduced effector memory Th1 responses to vaccine antigens were observed in HEU infants at 3 and 12 months and higher central memory Th1 responses to M. tuberculosis antigens were observed at 3 months only. Long-term monitoring of

HIV-positive pregnant women attending the prevention of mother-to-child transmission of HIV/AIDS (PMTCT) services in Ethiopia: economic productivity losses across urban-rural settings.

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Zegeye, Elias Asfaw; Mbonigaba, Josue; Kaye, Sylvia Blanche

2018-06-01

HIV/AIDS impacts significantly on pregnant women and on children in Ethiopia. This impact has a multiplier effect on household economies and on productivity losses, and is expected to vary across rural and urban settings. Applying the human capital approach to data collected from 131 respondents, this study estimated productivity losses per HIV-positive pregnant woman-infant pair across urban and rural health facilities in Ethiopia, which in turn were used to estimate the national productivity loss. The study found that the annual productivity loss per woman-infant pair was Ethiopian birr (ETB) 7,433 or United States dollar (US$) 378 and ETB 625 (US$ 32) in urban and rural settings, respectively. The mean patient days lost per year due to inpatient admission at hospitals/health centres was 11 in urban and 22 in rural health facilities. On average, urban home care-givers spent 20 (SD = 21) days annually providing home care services, while their rural counterparts spent 23 days (SD = 26). The productivity loss accounted for 16% and 7% of household income in urban and rural settings, respectively. These high and varying productivity losses require preventive interventions that are appropriate to each setting to ensure the welfare of women and children in Ethiopia.

Augmentation of antigen-specific immune responses using DNA-fusogenic liposome vaccine

International Nuclear Information System (INIS)

Yoshikawa, Tomoaki; Imazu, Susumu; Gao Jianqing; Hayashi, Kazuyuki; Tsuda, Yasuhiro; Shimokawa, Mariko; Sugita, Toshiki; Niwa, Takako; Oda, Atushi; Akashi, Mitsuru; Tsutsumi, Yasuo; Mayumi, Tadanori; Nakagawa, Shinsaku

2004-01-01

In an attempt to enhance the immunological efficacy of genetic immunization, we investigated a new biological means for delivering antigen gene directly to the cytoplasm via membrane fusion. In this context, we investigated fusogenic liposome (FL) encapsulating DNA as a possible genetic immunization vehicle. RT-PCR analysis indicated that a FL could introduce and express encapsulating OVA gene efficiently and rapidly in vitro. Consistent with this observation, an in vitro assay showed that FL-mediated antigen-gene delivery can induce potent presentation of antigen via the MHC class I-dependent pathway. Accordingly, immunization with FL containing the OVA-gene induced potent OVA-specific Th1 and Th2 cytokine production. Additionally, OVA-specific CTL responses and antibody production were also observed in systemic compartments including the spleen, upon immunization with the OVA-gene encapsulating FL. These findings suggest that FL is an effective genetic immunization carrier system for the stimulation of antigen-specific immune responses against its encoding antigen

Carcinoma-associated antigens

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Bartorelli, A.; Accinni, R.

1981-01-01

This invention relates to novel antigens associated with breast carcinoma, anti-sera specific to said antigens, 125 I-labeled forms of said antigens and methods of detecting said antigens in serum or plasma. The invention also relates to a diagnostic kit containing standardised antigens or antisera or marked forms thereof for the detection of said antigens in human blood, serum or plasma. (author)

Combination of anti-retroviral drugs and radioimmunotherapy specifically kills infected cells from HIV infected individuals

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Dina Tsukrov

2016-09-01

Full Text Available Eliminating virally infected cells is an essential component of any HIV eradication strategy. Radioimmunotherapy (RIT, a clinically established method for killing cells using radiolabeled antibodies, was recently applied to target HIV-1 gp41 antigen expressed on the surface of infect-ed cells. Since gp41 expression by infected cells is likely down-regulated in patients on an-tiretroviral therapy (ART, we evaluated the ability of RIT to kill ART-treated infected cells us-ing both in vitro models and lymphocytes isolated from HIV-infected subjects. Human peripheral blood mononuclear cells (PBMCs were infected with HIV and cultured in the presence of two clinically relevant ART combinations. Scatchard analysis of the 2556 human monoclonal anti-body to HIV gp41 binding to the infected and ART-treated cells demonstrated sufficient residual expression of gp41 on the cell surface to warrant subsequent RIT. This is the first time the quantification of gp41 post-ART is being reported. Cells were then treated with Bismuth-213-labeled 2556 antibody. conjugated to the human monoclonal antibody 2556, which binds to HIV gp41. Cell survival was quantified by Trypan blue and residual viremia by p24 ELISA. Cell surface gp41 expression was assessed by Scatchard analysis. The experiments were repeated using PBMCs isolated from blood specimens obtained from 15 HIV-infected individuals: ten on ART and five ART-naive. We found that 213Bi-2556 killed ART-treated infected PBMCs and reduced viral production to undetectable levels. ART and RIT co-treatment was more effective at reducing viral load in vitro than either therapy alone, indicating that gp41 expression under ART was sufficient to allow 213Bi-2556 to deliver cytocidal doses of radiation to infected cells. This study provides proof of concept that 213Bi-2556 may represent an innovative and effective targeting method for killing HIV-infected cells treated with ART, and supports continued development of 213Bi

Immunity to tumour antigens.

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Li, Geng; Ali, Selman A; McArdle, Stephanie E B; Mian, Shahid; Ahmad, Murrium; Miles, Amanda; Rees, Robert C

2005-01-01

During the last decade, a large number of human tumour antigens have been identified. These antigens are classified as tumour-specific shared antigens, tissue-specific differentiation antigens, overexpressed antigens, tumour antigens resulting from mutations, viral antigens and fusion proteins. Antigens recognised by effectors of immune system are potential targets for antigen-specific cancer immunotherapy. However, most tumour antigens are self-proteins and are generally of low immunogenicity and the immune response elicited towards these tumour antigens is not always effective. Strategies to induce and enhance the tumour antigen-specific response are needed. This review will summarise the approaches to discovery of tumour antigens, the current status of tumour antigens, and their potential application to cancer treatment.

Use of Ionizing Radiations to Prepare Radiovaccines and Radio-Antigens

International Nuclear Information System (INIS)

Tumanyan, MA; Hruschev, V.G.

1967-01-01

The possibility of employing ionizing radiations at certain doses to kill micro-organisms was used to produce vaccines against intestinal infections, and also to obtain from these bacteria antigens capable of being used as chemical vaccines. Typhoid fever and dysentery radiovaccines and radio-antigens were prepared, and the effect of various gamma ray doses on their toxicity and their antigenic and immunogenic properties was tested. The doses used did not change properties of these products as compared with those of vaccines and antigens produced by normal means. The paper also discusses the possibility of using radiation to sterilize fabricated vaccines and antigens, including radiovaccines and radio-antigens, anitoxins, antitoxic serums and nutrient media for the culture of micro-organisms. Data on the irradiation apparatus used for these investigations are reported. (author) [ru

Novel engineered HIV-1 East African Clade-A gp160 plasmid construct induces strong humoral and cell-mediated immune responses in vivo

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Muthumani, Karuppiah; Zhang Donghui; Dayes, Nathanael S.; Hwang, Daniel S.; Calarota, Sandra A.; Choo, Andrew Y.; Boyer, Jean D.; Weiner, David B.

2003-01-01

HIV-1 sequences are highly diverse due to the inaccuracy of the viral reverse transcriptase. This diversity has been studied and used to categorize HIV isolates into subtypes or clades, which are geographically distinct. To develop effective vaccines against HIV-1, immunogens representing different subtypes may be important for induction of cross-protective immunity, but little data exist describing and comparing the immunogenicity induced by different subtype-based vaccines. This issue is further complicated by poor expression of HIV structural antigens due to rev dependence. One costly approach is to codon optimize each subtype construct to be examined. Interestingly, cis-acting transcriptional elements (CTE) can also by pass rev restriction by a rev independent export pathway. We reasoned that rev+CTE constructs might have advantages for such expression studies. A subtype A envelope sequence from a viral isolate from east Africa was cloned into a eukaryotic expression vector under the control of the CMV-IE promoter. The utility of inclusion of the Mason-Pfizer monkey virus (MPV)-CTE with/without rev for driving envelope expression and immunogenicity was examined. Expression of envelope (gp120) was confirmed by immunoblot analysis and by pseudotype virus infectivity assays. The presence of rev and the CTE together increased envelope expression and viral infection. Furthermore the CTE+rev construct was significantly more immunogenic then CTE alone vector. Isotype analysis and cytokine profiles showed strong Th1 response in plasmid-immunized mice, which also demonstrated the superior nature of the rev+CTE construct. These responses were of similar or greater magnitude to a codon-optimized construct. The resulting cellular immune responses were highly cross-reactive with a HIV-1 envelope subtype B antigen. This study suggests a simple strategy for improving the expression and immunogenicity of HIV subtype-specific envelope antigens as plasmid or vector

Construction, expression, purification and biotin labeling of a single recombinant multi-epitope antigen for double-antigen sandwich ELISA to detect hepatitis C virus antibody.

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He, Jing; Xiu, Bingshui; Wang, Guohua; Chen, Kun; Feng, Xiaoyan; Song, Xiaoguo; Zhu, Cuixia; Yang, Xiqin; Bai, Guanzhong; Ling, Shigan; Zhang, Heqiu

2011-08-01

Based on B cell epitope predictions, a recombinant antigen with multiple epitopes from four Hepatitis C Virus fragments (C, NS3, NS4 and NS5) were engineered. The recombinant gene was then highly expressed in E. coli. The non-modified and C-terminal-modified recombinant proteins were used for coating and biotin labeling, respectively, to establish the double-antigen sandwich ELISA. Ten positive reference samples confirmed by the CHIRON RIBA HCV 3.0 SIA kit were detected positive, Forty one plasma samples were positive among samples from 441 volunteers, which indicated that the recombinant antigen could readily react well with plasma HCV antibody. As critical reagents of double-antigen sandwich ELISA, the recombinant multi-epitope antigen and the C-terminal-modified and biotin-conjugated antigen show good antigenicity. In this study, we provide a simple approach to produce multiple epitopes within one recombinant protein in order to avoid the costly expression of less-effective pools of multiple proteins, which is the conventional strategy of diagnostic antigen production for HCV antibody detection.

Diminished CD103 (aEb7 Expression on Resident T cells from the Female Genital Tract of HIV-positive women

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David C. Moylan

2017-01-01

Full Text Available Background:Tissue resident memory T cells (TrM provide an enhanced response against infection at mucosal surfaces, yet their function has not been extensively studied in humans, including the female genital tract (FGT. Methods: Using polychromatic flow cytometry, we studied TrM cells, defined as CD62L-CCR7-CD103+CD69+ CD4+ and CD8+ T cells in mucosa-derived T cells from healthy and HIV-positive women. Results: We demonstrate that TrM are present in the FGT of healthy and HIV-positive women. The expression of the mucosal retention receptor, CD103, from HIV-positive women was reduced compared to healthy women and was lowest in women with CD4 counts < 500 cells/mm3. Furthermore, CD103 expression on mucosa-derived CD8+ T cells correlated with antigen-specific IFN-γ production by mucosal CD4+ T cells and was inversely correlated with T-bet from CD8+CD103+ mucosa-derived T cells. Conclusions: These data suggest that CD4+ T cells, known to be impaired during HIV-1 infection and necessary for the expression of CD103 in murine models, may play a role in the expression of CD103 on resident T cells from the human FGT.

Nitric oxide production in the exhaled air of patients with pulmonary tuberculosis in relation to HIV co-infection

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Melese Endalkachew

2008-10-01

Full Text Available Abstract Background Nitric oxide (NO is essential for host defense in rodents, but the role of NO during tuberculosis (TB in man remains controversial. However, earlier observations that arginine supplementation facilitates anti-TB treatment, supports the hypothesis that NO is important in the host defense against TB. Local production of NO measured in fractional exhaled air (FeNO in TB patients with and without HIV co-infection has not been reported previously. Thus, our aim was to investigate levels of FeNO in relation to clinical symptoms and urinary NO metabolites (uNO. Methods In a cross sectional study, FeNO and uNO were measured and clinical symptoms, chest x-ray, together with serum levels of arginine, tumor necrosis factor alpha (TNF-alpha and interleukin 12 (IL-12 were evaluated in sputum smear positive TB patients (HIV+/TB, n = 36, HIV-/TB, n = 59, their household contacts (n = 17 and blood donors (n = 46 from Gondar University Hospital, Ethiopia. Results The proportion of HIV-/TB patients with an increased FeNO level (> 25 ppb was significantly higher as compared to HIV+/TB patients, but HIV+/TB patients had significantly higher uNO than HIV-/TB patients. HIV+ and HIV-/TB patients both had lower levels of FeNO compared to blood donors and household contacts. The highest levels of both uNO and FeNO were found in household contacts. Less advanced findings on chest x-ray, as well as higher sedimentation rate were observed in HIV+/TB patients as compared to HIV-/TB patients. However, no significant correlation was found between FeNO and uNO, chest x-ray grading, clinical symptoms, TNF-alpha, IL-12, arginine levels or sedimentation rate. Conclusion In both HIV negative and HIV co infected TB patients, low levels of exhaled NO compared to blood donors and household were observed. Future studies are needed to confirm whether low levels of exhaled NO could be a risk factor in acquiring TB and the relative importance of NO in human TB.

Differences in serum IgA responses to HIV-1 gp41 in elite controllers compared to viral suppressors on highly active antiretroviral therapy.

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Rafiq Nabi

Full Text Available Mechanisms responsible for natural control of human immunodeficiency type 1 (HIV replication in elite controllers (EC remain incompletely defined. To determine if EC generate high quality HIV-specific IgA responses, we used Western blotting to compare the specificities and frequencies of IgA to HIV antigens in serum of gender-, age- and race-matched EC and aviremic controllers (HC and viremic noncontrollers (HN on highly active antiretroviral therapy (HAART. Concentrations and avidity of IgA to HIV antigens were measured using ELISA or multiplex assays. Measurements for IgG were performed in parallel. EC were found to have stronger p24- and V1V2-specific IgG responses than HN, but there were no IgG differences for EC and HC. In contrast, IgA in EC serum bound more frequently to gp160 and gag proteins than IgA in HC or HN. The avidity of anti-gp41 IgA was also greater in EC, and these subjects had stronger IgA responses to the gp41 heptad repeat region 1 (HR1, a reported target of anti-bacterial RNA polymerase antibodies that cross react with gp41. However, EC did not demonstrate greater IgA responses to E. coli RNA polymerase or to peptides containing the shared LRAI sequence, suggesting that most of their HR1-specific IgA antibodies were not induced by intestinal microbiota. In both EC and HAART recipients, the concentrations of HIV-specific IgG were greater than HIV-specific IgA, but their avidities were comparable, implying that they could compete for antigen. Exceptions were C1 peptides and V1V2 loops. IgG and IgA responses to these antigens were discordant, with IgG reacting to V1V2, and IgA reacting to C1, especially in EC. Interestingly, EC with IgG hypergammaglobulinemia had greater HIV-specific IgA and IgG responses than EC with normal total IgG levels. Heterogeneity in EC antibody responses may therefore be due to a more focused HIV-specific B cell response in some of these individuals. Overall, these data suggest that development of

Anti-viral drug treatment along with immune activator IL-2: a control-based mathematical approach for HIV infection

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Nath Chatterjee, Amar; Roy, Priti Kumar

2012-02-01

Recent development in antiretroviral treatment against HIV can help AIDS patients to fight against HIV. But the question that whether the disease is to be partially or totally eradicated from HIV infected individuals still remains unsolved. Usually, the most effective treatment for the disease is HAART which can only control the disease progression. But as the immune system becomes weak, the patients can not fight against other diseases. Immune cells are activated and proliferated by IL-2 after the identification of antigen. IL-2 production is impaired in HIV positive patients and intermitted administration of immune activator IL-2 together with HAART which is a more effective treatment to fight against the disease. Thus, its expediency is essential and is yet to be explored. In this article we anticipated a mathematical model of the effect of IL-2 together with RTIs therapy in HIV positive patients. Our analytical as well as numerical study shows that the optimal schedule of treatment for best result is to be obtained by systematic drug therapy. But at the last stage of treatment, the infection level raises again due to minimisation of drug dosage. Thus we study the perfect adherence of the drugs and found out if RTIs are taken with sufficient interval then for fixed interval of IL-2 therapy, certain amount of drug dosages may be able to sustain the immune system at pre-infection stage and the infected CD4+T cells are going towards extinction.

I-125 input into antibodies molecules specific to australian antigen

International Nuclear Information System (INIS)

Abdukayumov, A. M.; Chistyakov, P.G.; Garajshina, G. R.

1999-01-01

There are experimental data on I-125 input into antibodies molecules specific to superficial antigen of hepatitis B virus (australian antigen). Three ways of input are submitted: with the help of T chloramine usage, Bolton-Hunter Reagent and with the help of iodogen. There are also comparative characteristics of iodized products obtained: molar radioactivity, radiochemical frequency, immuno - reactivity. The report also discusses advantages and disadvantages of the used methods for inputting I-125 into antibodies to australian antigen in order to study the possibility of creating radio immunological test system for detecting superficial antigen of B hepatitis

Limited transplantation of antigen-expressing hematopoietic stem cells induces long-lasting cytotoxic T cell responses.

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Warren L Denning

2011-02-01

Full Text Available Harnessing the ability of cytotoxic T lymphocytes (CTLs to recognize and eradicate tumor or pathogen-infected cells is a critical goal of modern immune-based therapies. Although multiple immunization strategies efficiently induce high levels of antigen-specific CTLs, the initial increase is typically followed by a rapid contraction phase resulting in a sharp decline in the frequency of functional CTLs. We describe a novel approach to immunotherapy based on a transplantation of low numbers of antigen-expressing hematopoietic stem cells (HSCs following nonmyeloablative or partially myeloablative conditioning. Continuous antigen presentation by a limited number of differentiated transgenic hematopoietic cells results in an induction and prolonged maintenance of fully functional effector T cell responses in a mouse model. Recipient animals display high levels of antigen-specific CTLs four months following transplantation in contrast to dendritic cell-immunized animals in which the response typically declines at 4-6 weeks post-immunization. Majority of HSC-induced antigen-specific CD8+ T cells display central memory phenotype, efficiently kill target cells in vivo, and protect recipients against tumor growth in a preventive setting. Furthermore, we confirm previously published observation that high level engraftment of antigen-expressing HSCs following myeloablative conditioning results in tolerance and an absence of specific cytotoxic activity in vivo. In conclusion, the data presented here supports potential application of immunization by limited transplantation of antigen-expressing HSCs for the prevention and treatment of cancer and therapeutic immunization of chronic infectious diseases such as HIV-1/AIDS.

Unusual antigen presentation offers new insight into HIV vaccine design.

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McMichael, Andrew J; Picker, Louis J

2017-06-01

Recent findings with a rhesus monkey cytomegalovirus based simian immunodeficiency virus vaccine have identified strong CD8+ T cell responses that are restricted by MHC-E. Also mycobacteria specific CD8+ T cells, that are MHC-E restricted, have been identified. MHC-E therefore can present a wide range of epitope peptides to CD8+ T cells, alongside its well defined role in presenting a conserved MHC-class I signal peptide to the NKG2A/C-CD94 receptor on natural killer cells. Here we explore the antigen processing pathways involved in these atypical T cell responses. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

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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.

Improving Mycobacterium bovis bacillus Calmette-Guèrin as a vaccine delivery vector for viral antigens by incorporation of glycolipid activators of NKT cells.

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Venkataswamy, Manjunatha M; Ng, Tony W; Kharkwal, Shalu S; Carreño, Leandro J; Johnson, Alison J; Kunnath-Velayudhan, Shajo; Liu, Zheng; Bittman, Robert; Jervis, Peter J; Cox, Liam R; Besra, Gurdyal S; Wen, Xiangshu; Yuan, Weiming; Tsuji, Moriya; Li, Xiangming; Ho, David D; Chan, John; Lee, Sunhee; Frothingham, Richard; Haynes, Barton F; Panas, Michael W; Gillard, Geoffrey O; Sixsmith, Jaimie D; Korioth-Schmitz, Birgit; Schmitz, Joern E; Larsen, Michelle H; Jacobs, William R; Porcelli, Steven A

2014-01-01

Recombinant Mycobacterium bovis bacillus Calmette-Guèrin (rBCG) has been explored as a vector for vaccines against HIV because of its ability to induce long lasting humoral and cell mediated immune responses. To maximize the potential for rBCG vaccines to induce effective immunity against HIV, various strategies are being employed to improve its ability to prime CD8+ T cells, which play an important role in the control of HIV infections. In this study we adopted a previously described approach of incorporating glycolipids that activate CD1d-restricted natural killer T (NKT) cells to enhance priming of CD8+ T cells by rBCG strains expressing an SIV Gag antigen (rBCG-SIV gag). We found that the incorporation of the synthetic NKT activating glycolipid α-galactosylceramide (α-GC) into rBCG-SIV gag significantly enhanced CD8+ T cell responses against an immunodominant Gag epitope, compared to responses primed by unmodified rBCG-SIV gag. The abilities of structural analogues of α-GC to enhance CD8+ T cell responses to rBCG were compared in both wild type and partially humanized mice that express human CD1d molecules in place of mouse CD1d. These studies identified an α-GC analogue known as 7DW8-5, which has previously been used successfully as an adjuvant in non-human primates, as a promising compound for enhancing immunogenicity of antigens delivered by rBCG.vectors. Our findings support the incorporation of synthetic glycolipid activators of NKT cells as a novel approach to enhance the immunogenicity of rBCG-vectored antigens for induction of CD8+ T cell responses. The glycolipid adjuvant 7DW8-5 may be a promising candidate for advancing to non-human primate and human clinical studies for the development of HIV vaccines based on rBCG vectors.

Improving Mycobacterium bovis bacillus Calmette-Guèrin as a vaccine delivery vector for viral antigens by incorporation of glycolipid activators of NKT cells.

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Manjunatha M Venkataswamy

Full Text Available Recombinant Mycobacterium bovis bacillus Calmette-Guèrin (rBCG has been explored as a vector for vaccines against HIV because of its ability to induce long lasting humoral and cell mediated immune responses. To maximize the potential for rBCG vaccines to induce effective immunity against HIV, various strategies are being employed to improve its ability to prime CD8+ T cells, which play an important role in the control of HIV infections. In this study we adopted a previously described approach of incorporating glycolipids that activate CD1d-restricted natural killer T (NKT cells to enhance priming of CD8+ T cells by rBCG strains expressing an SIV Gag antigen (rBCG-SIV gag. We found that the incorporation of the synthetic NKT activating glycolipid α-galactosylceramide (α-GC into rBCG-SIV gag significantly enhanced CD8+ T cell responses against an immunodominant Gag epitope, compared to responses primed by unmodified rBCG-SIV gag. The abilities of structural analogues of α-GC to enhance CD8+ T cell responses to rBCG were compared in both wild type and partially humanized mice that express human CD1d molecules in place of mouse CD1d. These studies identified an α-GC analogue known as 7DW8-5, which has previously been used successfully as an adjuvant in non-human primates, as a promising compound for enhancing immunogenicity of antigens delivered by rBCG.vectors. Our findings support the incorporation of synthetic glycolipid activators of NKT cells as a novel approach to enhance the immunogenicity of rBCG-vectored antigens for induction of CD8+ T cell responses. The glycolipid adjuvant 7DW8-5 may be a promising candidate for advancing to non-human primate and human clinical studies for the development of HIV vaccines based on rBCG vectors.

HIV, hepatitis B, and hepatitis C in Zambia

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Kenneth C Kapembwa

2011-01-01

Full Text Available Objectives : Epidemiologic data of HIV and viral hepatitis coinfection are needed in sub-Saharan Africa to guide health policy for hepatitis screening and optimized antiretroviral therapy (ART. Materials and Methods: We screened 323 HIV-infected, ART-eligible adults for hepatitis B surface antigen (HBsAg and hepatitis C antibody (HCV Ab at a tertiary hospital in Lusaka, Zambia. We collected basic demographic, medical, and laboratory data to determine predictors for coinfection. Results: Of 323 enrolled patients, 32 (9.9%; 95% CI=6.7-13.2% were HBsAg positive, while 4 (1.2%; 95% CI=0.03-2.4% were HCV Ab positive. Patients with hepatitis B coinfection were more likely to be 200 IU/L was uncommon and did not differ between the two groups (3.4% vs. 2.3%; P=0.5. We were unable to determine predictors of hepatitis C infection due to the low prevalence of disease. Conclusions: HIV and hepatitis B coinfection was common among patients initiating ART at this tertiary care facility. Routine screening for hepatitis B should be considered for HIV-infected persons in southern Africa.

Complement and the control of HIV infection: an evolving story.

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Frank, Michael M; Hester, Christopher; Jiang, Haixiang

2014-05-01

Thirty years ago, investigators isolated and later determined the structure of HIV-1 and its envelope proteins. Using techniques that were effective with other viruses, they prepared vaccines designed to generate antibody or T-cell responses, but they were ineffective in clinical trials. In this article, we consider the role of complement in host defense against enveloped viruses, the role it might play in the antibody response and why complement has not controlled HIV-1 infection. Complement consists of a large group of cell-bound and plasma proteins that are an integral part of the innate immune system. They provide a first line of defense against microbes and also play a role in the immune response. Here we review the studies of complement-mediated HIV destruction and the role of complement in the HIV antibody response. HIV-1 has evolved a complex defense to prevent complement-mediated killing reviewed here. As part of these studies, we have discovered that HIV-1 envelope, on administration into animals, is rapidly broken down into small peptides that may prove to be very inefficient at provident the type of antigenic stimulation that leads to an effective immune response. Improving complement binding and stabilizing envelope may improve the vaccine response.

The National NeuroAIDS Tissue Consortium brain gene array: two types of HIV-associated neurocognitive impairment.

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Benjamin B Gelman

Full Text Available The National NeuroAIDS Tissue Consortium (NNTC performed a brain gene expression array to elucidate pathophysiologies of Human Immunodeficiency Virus type 1 (HIV-1-associated neurocognitive disorders.Twenty-four human subjects in four groups were examined A Uninfected controls; B HIV-1 infected subjects with no substantial neurocognitive impairment (NCI; C Infected with substantial NCI without HIV encephalitis (HIVE; D Infected with substantial NCI and HIVE. RNA from neocortex, white matter, and neostriatum was processed with the Affymetrix® array platform.With HIVE the HIV-1 RNA load in brain tissue was three log(10 units higher than other groups and over 1,900 gene probes were regulated. Interferon response genes (IFRGs, antigen presentation, complement components and CD163 antigen were strongly upregulated. In frontal neocortex downregulated neuronal pathways strongly dominated in HIVE, including GABA receptors, glutamate signaling, synaptic potentiation, axon guidance, clathrin-mediated endocytosis and 14-3-3 protein. Expression was completely different in neuropsychologically impaired subjects without HIVE. They had low brain HIV-1 loads, weak brain immune responses, lacked neuronally expressed changes in neocortex and exhibited upregulation of endothelial cell type transcripts. HIV-1-infected subjects with normal neuropsychological test results had upregulation of neuronal transcripts involved in synaptic transmission of neostriatal circuits.Two patterns of brain gene expression suggest that more than one pathophysiological process occurs in HIV-1-associated neurocognitive impairment. Expression in HIVE suggests that lowering brain HIV-1 replication might improve NCI, whereas NCI without HIVE may not respond in kind; array results suggest that modulation of transvascular signaling is a potentially promising approach. Striking brain regional differences highlighted the likely importance of circuit level disturbances in HIV/AIDS. In

Cytokine expression of macrophages in HIV-1-associated vacuolar myelopathy.

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Tyor, W R; Glass, J D; Baumrind, N; McArthur, J C; Griffin, J W; Becker, P S; Griffin, D E

1993-05-01

Macrophages are frequently present within the periaxonal and intramyelinic vacuoles that are located primarily in the posterior and lateral funiculi of the thoracic spinal cord in HIV-associated vacuolar myelopathy. But the role of these macrophages in the formation of the vacuoles is unclear. One hypothesis is that cytokines, such as interleukin-1 (IL-1) and tumor necrosis factor (TNF)-alpha, are produced locally by macrophages and have toxic effects on myelin or oligodendrocytes. The resulting myelin damage eventually culminates in the removal of myelin by macrophages and vacuole formation. We studied thoracic spinal cord specimens taken at autopsy from HIV-positive (+) and HIV-negative individuals. The predominant mononuclear cells present in HIV+ spinal cords are macrophages. They are located primarily in the posterior and lateral funiculi regardless of the presence or absence of vacuolar myelopathy. Macrophages and microglia are more frequent in HIV+ than HIV-negative individuals and these cells frequently stain for class I and class II antigens, IL-1, and TNF-alpha. Activated macrophages positive for IL-1 and TNF-alpha are great increased in the posterior and lateral funiculi of HIV+ individuals with and without vacuolar myelopathy, suggesting they are present prior to the development of vacuoles. Cytokines, such as TNF-alpha, may be toxic for myelin or oligodendrocytes, leading to myelin damage and removal by macrophages and vacuole formation.

Determination of HIV status of infants born to HIV-infected mothers: A review of the diagnostic methods with special focus on the applicability of p24 antigen testing in developing countries

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Wessman, Maria J; Theilgaard, Zahra Persson; Katzenstein, Terese L

2012-01-01

Abstract In 2009, 2.5 million children under the age of 15 y were living with human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS); 370,000 were diagnosed with HIV and 260,000 died due to AIDS. More than 90% of the children infected with HIV live in sub-Saharan Africa. Most...... children infected with HIV contract the infection in utero, during delivery, or via breast milk. This review outlines the current diagnostic methods to determine the HIV status of infants born to HIV-infected mothers. The HIV DNA and RNA polymerase chain reaction (PCR) tests are highly accurate...

Simian Immunodeficiency Virus (SIV-Specific Chimeric Antigen Receptor-T Cells Engineered to Target B Cell Follicles and Suppress SIV Replication

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Kumudhini Preethi Haran

2018-03-01

Full Text Available There is a need to develop improved methods to treat and potentially cure HIV infection. During chronic HIV infection, replication is concentrated within T follicular helper cells (Tfh located within B cell follicles, where low levels of virus-specific CTL permit ongoing viral replication. We previously showed that elevated levels of simian immunodeficiency virus (SIV-specific CTL in B cell follicles are linked to both decreased levels of viral replication in follicles and decreased plasma viral loads. These findings provide the rationale to develop a strategy for targeting follicular viral-producing (Tfh cells using antiviral chimeric antigen receptor (CAR T cells co-expressing the follicular homing chemokine receptor CXCR5. We hypothesize that antiviral CAR/CXCR5-expressing T cells, when infused into an SIV-infected animal or an HIV-infected individual, will home to B cell follicles, suppress viral replication, and lead to long-term durable remission of SIV and HIV. To begin to test this hypothesis, we engineered gammaretroviral transduction vectors for co-expression of a bispecific anti-SIV CAR and rhesus macaque CXCR5. Viral suppression by CAR/CXCR5-transduced T cells was measured in vitro, and CXCR5-mediated migration was evaluated using both an in vitro transwell migration assay, as well as a novel ex vivo tissue migration assay. The functionality of the CAR/CXCR5 T cells was demonstrated through their potent suppression of SIVmac239 and SIVE660 replication in in vitro and migration to the ligand CXCL13 in vitro, and concentration in B cell follicles in tissues ex vivo. These novel antiviral immunotherapy products have the potential to provide long-term durable remission (functional cure of HIV and SIV infections.

Serological screening for sexually transmitted infections in pregnancy: is there any value in re-screening for HIV and syphilis at the time of delivery?

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Qolohle, D C; Hoosen, A A; Moodley, J; Smith, A N; Mlisana, K P

1995-01-01

OBJECTIVE--The aim of this study was to assess the prevalence of syphilis, human immunodeficiency virus (HIV), and hepatitis B virus (HBV) infections in women at the time of delivery, and to determine the seroconversion rates for syphilis and HIV infections from initial booking visit to delivery. SETTING--The labour ward of a typical tertiary hospital in a developing country and serving an indigent African population. METHOD--Four hundred and eighteen women presenting in labour were randomly selected and informed consent obtained for serological testing for syphilis and HBV infections in umbilical cord blood samples. The specimens were then given a study number, the gestational ages recorded and anonymously tested for HIV infection. RESULTS--Of the 191 women who had antenatal care, 13 (6.8%) were HIV antibody positive at the initial "booking" visit. An additional 4 were found to be HIV antibody positive at the time of delivery resulting in a seroconversion rate of 2.2%. The seroconversion rate for syphilis at the time of delivery was 2.7%. Hepatitis B surface antigens were detected in only 2 women, one of whom was antigen positive. CONCLUSION--The high seroconversion rates for both syphilis and HIV infection in pregnancy justifies re-screening for these conditions in endemic areas such as ours. PMID:7744414

Effect of BSA Antigen Sensitization during the Acute Phase of Influenza A Viral Infection on CD11c+ Pulmonary Antigen Presenting Cells

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Fumitaka Sato

2009-01-01

Conclusions: BSA antigen sensitization during the acute phase of influenza A viral infection enhanced IL-10 production from naive CD4+ T cell interaction with CD11c+ pulmonary APCs. The IL-10 secretion evoked Th2 responses in the lungs with downregulation of Th1 responses and was important for the eosinophil recruitment into the lungs after BSA antigen challenge.

HIV gp120 binds to mannose receptor on vaginal epithelial cells and induces production of matrix metalloproteinases.

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Sashaina E Fanibunda

Full Text Available BACKGROUND: During sexual transmission of HIV in women, the virus breaches the multi-layered CD4 negative stratified squamous epithelial barrier of the vagina, to infect the sub-epithelial CD4 positive immune cells. However the mechanisms by which HIV gains entry into the sub-epithelial zone is hitherto unknown. We have previously reported human mannose receptor (hMR as a CD4 independent receptor playing a role in HIV transmission on human spermatozoa. The current study was undertaken to investigate the expression of hMR in vaginal epithelial cells, its HIV gp120 binding potential, affinity constants and the induction of matrix metalloproteinases (MMPs downstream of HIV gp120 binding to hMR. PRINCIPAL FINDINGS: Human vaginal epithelial cells and the immortalized vaginal epithelial cell line Vk2/E6E7 were used in this study. hMR mRNA and protein were expressed in vaginal epithelial cells and cell line, with a molecular weight of 155 kDa. HIV gp120 bound to vaginal proteins with high affinity, (Kd = 1.2±0.2 nM for vaginal cells, 1.4±0.2 nM for cell line and the hMR antagonist mannan dose dependently inhibited this binding. Both HIV gp120 binding and hMR exhibited identical patterns of localization in the epithelial cells by immunofluorescence. HIV gp120 bound to immunopurified hMR and affinity constants were 2.9±0.4 nM and 3.2±0.6 nM for vaginal cells and Vk2/E6E7 cell line respectively. HIV gp120 induced an increase in MMP-9 mRNA expression and activity by zymography, which could be inhibited by an anti-hMR antibody. CONCLUSION: hMR expressed by vaginal epithelial cells has high affinity for HIV gp120 and this binding induces production of MMPs. We propose that the induction of MMPs in response to HIV gp120 may lead to degradation of tight junction proteins and the extracellular matrix proteins in the vaginal epithelium and basement membrane, leading to weakening of the epithelial barrier; thereby facilitating transport of HIV across the

[Prevalences of HIV, hepatitis B and hepatitis C in blood donors in the Republic of Djibouti].

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Dray, X; Dray-Spira, R; Bronstein, J A; Mattera, D

2005-01-01

Screening for hepatitis B (HBV) surface antigen (Ag HBs) and for antibodies to hepatitis C (HCV) and human: immunodeficiency virus (HIV) was carried out in 9006 volunteer blood donors at the National Blood Bank in the Republic of Djibouti from 1998 to 2000. Results demonstrated the presence of Ag HBs in 934 patients (10.4%), antibodies to HCV in 21 patients (0.3%), and antibodies to HIV in 175 patients (1.9%). In comparison with neighboring countries the prevalence of HBV, HCV, and HIV infection in Djibouti was low. These findings should be used to guide preventive action against these viral infections in the Republic of Djibouti. Estimations of HIV infection (11.7%) based on modeling by the World Health Organization should be reviewed.

Clinical Control of HIV-1 by Cytotoxic T Cells Specific for Multiple Conserved Epitopes.

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Murakoshi, Hayato; Akahoshi, Tomohiro; Koyanagi, Madoka; Chikata, Takayuki; Naruto, Takuya; Maruyama, Rie; Tamura, Yoshiko; Ishizuka, Naoki; Gatanaga, Hiroyuki; Oka, Shinichi; Takiguchi, Masafumi

2015-05-01

Identification and characterization of CD8(+) T cells effectively controlling HIV-1 variants are necessary for the development of AIDS vaccines and for studies of AIDS pathogenesis, although such CD8(+) T cells have been only partially identified. In this study, we sought to identify CD8(+) T cells controlling HIV-1 variants in 401 Japanese individuals chronically infected with HIV-1 subtype B, in which protective alleles HLA-B*57 and HLA-B*27 are very rare, by using comprehensive and exhaustive methods. We identified 13 epitope-specific CD8(+) T cells controlling HIV-1 in Japanese individuals, though 9 of these epitopes were not previously reported. The breadths of the T cell responses to the 13 epitopes were inversely associated with plasma viral load (P = 2.2 × 10(-11)) and positively associated with CD4 count (P = 1.2 × 10(-11)), indicating strong synergistic effects of these T cells on HIV-1 control in vivo. Nine of these epitopes were conserved among HIV-1 subtype B-infected individuals, whereas three out of four nonconserved epitopes were cross-recognized by the specific T cells. These findings indicate that these 12 epitopes are strong candidates for antigens for an AIDS vaccine. The present study highlighted a strategy to identify CD8(+) T cells controlling HIV-1 and demonstrated effective control of HIV-1 by those specific for 12 conserved or cross-reactive epitopes. HLA-B*27-restricted and HLA-B*57-restricted cytotoxic T lymphocytes (CTLs) play a key role in controlling HIV-1 in Caucasians and Africans, whereas it is unclear which CTLs control HIV-1 in Asian countries, where HLA-B*57 and HLA-B*27 are very rare. A recent study showed that HLA-B*67:01 and HLA-B*52:01-C*12:02 haplotypes were protective alleles in Japanese individuals, but it is unknown whether CTLs restricted by these alleles control HIV-1. In this study, we identified 13 CTLs controlling HIV-1 in Japan by using comprehensive and exhaustive methods. They included 5 HLA-B*52:01-restricted

Hepatitis B surface antigen (HBsAg) expression in plant cell culture: Kinetics of antigen accumulation in batch culture and its intracellular form.

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Smith, Mark L; Mason, Hugh S; Shuler, Michael L

2002-12-30

The production of edible vaccines in transgenic plants and plant cell culture may be improved through a better understanding of antigen processing and assembly. The hepatitis B surface antigen (HBsAg) was chosen for study because it undergoes substantial and complex post-translational modifications, which are necessary for its immunogenicity. This antigen was expressed in soybean (Glycine max L. Merr. cv Williams 82) and tobacco NT1 (Nicotiana tabacum L.) cell suspension cultures, and HBsAg production in batch culture was characterized. The plant-derived antigen consisted predominantly of disulfide cross-linked HBsAg protein (p24(s)) dimers, which were all membrane associated. Similar to yeast, the plant-expressed HBsAg was retained intracellularly. The maximal HBsAg titers were obtained with soybean suspension cultures (20-22 mg/L) with titers in tobacco cultures being approximately 10-fold lower. For soybean cells, electron microscopy and immunolocalization demonstrated that all the HBsAg was localized to the endoplasmic reticulum (ER) and provoked dilation and proliferation of the ER network. Sucrose gradient analysis of crude extracts showed that HBsAg had a complex size distribution uncharacteristic of the antigen's normal structure of uniform 22-nm virus-like particles. The extent of authentic epitope formation was assessed by comparing total p24(s) synthesized to that reactive by polyclonal and monoclonal immunoassays. Depending on culture age, between 40% and 100% of total p24(s) was polyclonal antibody reactive whereas between 6% and 37% was recognized by a commercial monoclonal antibody assay. Possible strategies to increase HBsAg production and improve post-translational processing are discussed. Copyright 2002 Wiley Periodicals, Inc.

Use of a Chagas Urine Nanoparticle Test (Chunap) to Correlate with Parasitemia Levels in T. cruzi/HIV Co-infected Patients

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Castro-Sesquen, Yagahira E.; Gilman, Robert H.; Mejia, Carolina; Clark, Daniel E.; Choi, Jeong; Reimer-McAtee, Melissa J.; Castro, Rosario; Valencia-Ayala, Edward; Flores, Jorge; Bowman, Natalie; Castillo-Neyra, Ricardo; Torrico, Faustino; Liotta, Lance; Bern, Caryn; Luchini, Alessandra

2016-01-01

Background Early diagnosis of reactivated Chagas disease in HIV patients could be lifesaving. In Latin America, the diagnosis is made by microscopical detection of the T. cruzi parasite in the blood; a diagnostic test that lacks sensitivity. This study evaluates if levels of T. cruzi antigens in urine, determined by Chunap (Chagas urine nanoparticle test), are correlated with parasitemia levels in T. cruzi/HIV co-infected patients. Methodology/Principal Findings T. cruzi antigens in urine of HIV patients (N = 55: 31 T. cruzi infected and 24 T. cruzi serology negative) were concentrated using hydrogel particles and quantified by Western Blot and a calibration curve. Reactivation of Chagas disease was defined by the observation of parasites in blood by microscopy. Parasitemia levels in patients with serology positive for Chagas disease were classified as follows: High parasitemia or reactivation of Chagas disease (detectable parasitemia by microscopy), moderate parasitemia (undetectable by microscopy but detectable by qPCR), and negative parasitemia (undetectable by microscopy and qPCR). The percentage of positive results detected by Chunap was: 100% (7/7) in cases of reactivation, 91.7% (11/12) in cases of moderate parasitemia, and 41.7% (5/12) in cases of negative parasitemia. Chunap specificity was found to be 91.7%. Linear regression analysis demonstrated a direct relationship between parasitemia levels and urine T. cruzi antigen concentrations (p 105 pg was chosen to determine patients with reactivation of Chagas disease (7/7). Antigenuria levels were 36.08 times (95% CI: 7.28 to 64.88) higher in patients with CD4+ lymphocyte counts below 200/mL (p = 0.016). No significant differences were found in HIV loads and CD8+ lymphocyte counts. Conclusion Chunap shows potential for early detection of Chagas reactivation. With appropriate adaptation, this diagnostic test can be used to monitor Chagas disease status in T. cruzi/HIV co-infected patients. PMID:26919324

Antigenic profile and localization of Clonorchis sinensis proteins in the course of infection

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Kim, Tae Yun; Song, Kye-Yong; Sohn, Woon-Mok; Kang, Shin-Yong

2001-01-01

In the course of Clonorchis sinensis infection, antigens presented to the hosts may be in a close relation to growth of the fluke. The antigenic proteins stimulating IgG antibody production were chronologically identified by immunoblot and localized by immunohistochemical staining. In the early stage of infection until 12 weeks post-infection (PI), antigens were proteins with molecular mass larger than 34 kDa which were derived from the tegument, testes and intrauterine eggs. After 20 weeks PI, antigens recognized were 29, 27 and 26 kDa proteins from the intestine, excretory bladder and reproductive organs. It is suggested that the tegumental proteins are the most potent antigens and the excretory-secretory proteins with middle molecular mass of 26-45 kDa contribute to the high level production of antibodies after 20 weeks of the C. sinensis infection. PMID:11775331

Homeostatic proliferation fails to efficiently reactivate HIV-1 latently infected central memory CD4+ T cells.

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Alberto Bosque

2011-10-01

Full Text Available Homeostatic proliferation ensures the longevity of central memory T-cells by inducing cell proliferation in the absence of cellular differentiation or activation. This process is governed mainly by IL-7. Central memory T-cells can also be stimulated via engagement of the T-cell receptor, leading to cell proliferation but also activation and differentiation. Using an in vitro model of HIV-1 latency, we have examined in detail the effects of homeostatic proliferation on latently infected central memory T cells. We have also used antigenic stimulation via anti-CD3/anti-CD28 antibodies and established a comparison with a homeostatic proliferation stimulus, to evaluate potential differences in how either treatment affects the dynamics of latent virus populations. First, we show that homeostatic proliferation, as induced by a combination of IL-2 plus IL-7, leads to partial reactivation of latent HIV-1 but is unable to reduce the size of the reservoir in vitro. Second, latently infected cells are able to homeostatically proliferate in the absence of viral reactivation or cell differentiation. These results indicate that IL-2 plus IL-7 may induce a detrimental effect by favoring the maintenance of the latent HIV-1 reservoir. On the other hand, antigenic stimulation efficiently reactivated latent HIV-1 in cultured central memory cells and led to depletion of the latently infected cells via virus-induced cell death.

Cryptococcal meningitis in HIV-infected patients at Chiang Mai University Hospital: a retrospective study.

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Chaiwarith, Romanee; Vongsanim, Surachet; Supparatpinyo, Khuanchai

2014-05-01

Cryptococcal meningitis (CM) is a common central nervous system infection in HIV-infected patients. This study aimed to determine treatment outcomes among HIV-infected patients who had cryptococcal meningitis and to determine predictors of death. We conducted a retrospective cohort study among HIV-infected patients receiving care at Chiang Mai University Hospital from January 1, 2005 to December 31, 2010. We studied 79 patients; 45 (57.0%) were male and the mean age was 35.1 +/- 7.2 years. Eleven patients (13.9%) had previous opportunistic infection. The most common presenting symptoms were headache (63 patients, 79.8%), fever (49 patients, 62.0%), and altered consciousness (21 patients, 26.6%). The median CD4+ cell count was 20 cells/mm3 [Interquartile range (IQR) 10, 53]. The in-hospital, 90-day, and 1-year mortality rates were 24.1%, 32.4%, and 52.2%, respectively. The CM attributable in-hospital, 90-day and 1-year mortality rates were 13.9%, 20.3%, and 23.2%, respectively. Predictors associated with a 1-year mortality were a high cerebrospinal (CSF) cryptococcal antigen titer (> 1:10,000) [Odds Ratio (OR) =7.08, 95% confidence interval (CI): 1.62-31.00, p = 0.009], and altered consciousness at presentation (OR = 5.27; 95% CI: 1.16-24.05; p = 0.032). Cryptococcal meningitis is an important cause of death in HIV-infected patients. HIV-infected patients with a low CD4+ cell count, a headache, fever and altered consciousness should be investigated for CM and those with a high CSF cryptococcal antigen titer are at high risk for mortality.

Epidemiological and clinical characteristics of hepatitis B virus in HIV-infected patients in Guangdong, China.

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Huang, S M; Cai, W P; Hu, F Y; Lan, Y; Liao, B L; Chen, Y P; Tang, X P

2016-09-01

This study investigated the epidemiological and clinical characteristics of hepatitis B virus (HBV) in HIV-infected adults at the time of antiretroviral therapy (ART) initiation in Guangdong province, China. A total of 2793 HIV-infected adults were enrolled between January 2004 and September 2011. Demographic data and laboratory parameters were collected, HBV-DNA levels were measured, and HBV genotypes were identified before ART initiation. The prevalence of hepatitis B surface antigen (HBsAg) in HIV-infected patients was 13.2%. A total of 266 HIV/HBV co-infected patients and 1469 HIV mono-infected patients were recruited. The median alanine aminotransferase and aspartate aminotransferase levels of HIV/HBV co-infected patients were higher than HIV mono-infected patients (32 U/L vs. 22 U/L, p HIV/HBV co-infected patients was lower than HIV mono-infected patients (59 cells/mm(3) vs. 141 cells/mm(3), p study indicates a high prevalence of HBsAg in HIV-infected adults in Guangdong. The level of CD4 cell count in HIV/HBV co-infected patients was much lower than HIV mono-infected patients, especially in patients who were HBeAg-positive and had a high level of HBV-DNA. The predominant HBV genotype in HIV/HBV co-infected patients is genotype B. © The Author(s) 2015.

IMPACT OF HIV INFECTION AND TUBERCULOSIS ON THE PERIPHERAL BLOOD T-CELL DIFFERENTIATION

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E. V. Vasileva

2017-01-01

Full Text Available Tuberculosis is the leading cause of death among HIV infected individuals. In this regard, an important task is the timely detection of tuberculosis in HIV infected patients. Previously, we have shown that the diagnostic value of in vitro test, QuantiFERON-TB Gold In-Tube is not decreased in patients with HIV infection against the background of tuberculosis. However, it remains unclear what kind of cell populations produce IFNγ in response to specific Mycobacterium tuberculosis antigens stimulation in vitro, because the immunodeficiency, caused by HIV, makes primarily for a decrease the abundance and attenuation functions of CD4 T-lymphocytes. The aim of thшы work was to compare the degree of differentiation of T-lymphocytes CD4 (Th and CD8 (Tcyt in patients with pulmonary tuberculosis and healthy donors against the background of HIV infection. The study data were obtained during the examination of 28 patients with pulmonary tuberculosis without HIV infection (HIV–TB+, 23 patients with HIV infection (TB–HIV+ and 30 patients coinfected with HIV and tuberculosis (TB+HIV+. The comparison group consisted of 37 healthy individuals (TB–HIV–. Аbsolute and abundance (relative content of major subpopulations of T-lymphocytes (based on the expression of CD27 marker, CD28, CD45RA and CD62L in the peripheral blood for all patients included in the study (n = 118 were evaluated by flow cytometry approach. For patients with pulmonary tuberculosis (n = 58 QuantiFERON-TB Gold In Tube (Qiagen, QFT test was performed. Th/Tcyt ratio was not significantly different among the groups of TB–HIV– and TB+HIV– (1.76 [1.51; 2.30] against 1.86 [1.22; 2.79], p = 0.960. At that time, the size of both subpopulations “terminally differentiated” Tcyt (Tcyt Eff, CD27–CD28– CD62L–CD45RA– Th lymphocytes and effector memory lymphocytes (Th EM, CD27–CD28+CD62L–CD45RA–, was significantly different in all four study groups. Multidirectional changes

Polyclonal antibodies for the detection of Trypanosoma cruzi circulating antigens.

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Edith S Málaga-Machaca

2017-11-01

Full Text Available Detection of Trypanosoma cruzi antigens in clinical samples is considered an important diagnostic tool for Chagas disease. The production and use of polyclonal antibodies may contribute to an increase in the sensitivity of immunodiagnosis of Chagas disease.Polyclonal antibodies were raised in alpacas, rabbits, and hens immunized with trypomastigote excreted-secreted antigen, membrane proteins, trypomastigote lysate antigen and recombinant 1F8 to produce polyclonal antibodies. Western blot analysis was performed to determine specificity of the developed antibodies. An antigen capture ELISA of circulating antigens in serum, plasma and urine samples was developed using IgY polyclonal antibodies against T. cruzi membrane antigens (capture antibody and IgG from alpaca raised against TESA. A total of 33 serum, 23 plasma and 9 urine samples were analyzed using the developed test. Among serum samples, compared to serology, the antigen capture ELISA tested positive in 55% of samples. All plasma samples from serology positive subjects were positive in the antigen capture ELISA. All urine positive samples had corresponding plasma samples that were also positive when tested by the antigen capture ELISA.Polyclonal antibodies are useful for detection of circulating antigens in both the plasma and urine of infected individuals. Detection of antigens is direct evidence of the presence of the parasite, and could be a better surrogate of current infection status.

HIV: mecanismo de replicação, alvos farmacológicos e inibição por produtos derivados de plantas HIV: replication mechanism, pharmacological targets and inhibition by products derived from plants

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Roberta Costa Santos Ferreira

2010-01-01

Full Text Available The AIDS epidemy has spread out and led to the diversification on the research for new antiviral drugs. Natural products, especially those derived from plants, are well-recognized as excellent sources of new drugs. Several of them have inhibitory activity against HIV replication, and some have been already clinically tested, with favorable results. This review presents the biochemical basis of the viral cycle and the research up to date on the identification, determination of the mechanism of biological action together with the therapeutical potential of plants-derived natural products, in the inhibition of HIV.

O-antigen protects gram-negative bacteria from histone killing.

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Catherine Chaput

Full Text Available Beyond their traditional role of wrapping DNA, histones display antibacterial activity to Gram-negative and -positive bacteria. To identify bacterial components that allow survival to a histone challenge, we selected resistant bacteria from homologous Escherichia coli libraries that harbor plasmids carrying pieces of the chromosome in different sizes. We identified genes required for exopolysaccharide production and for the synthesis of the polysaccharide domain of the lipopolysaccharide, called O-antigen. Indeed, O-antigen and exopolysaccharide conferred further resistance to histones. Notably, O-antigen also conferred resistance to histones in the pathogens Shigella flexneri and Klebsiella pneumoniae.

Health economics of blood transfusion safety--focus on sub-Saharan Africa.

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van Hulst, Marinus; Smit Sibinga, Cees Th; Postma, Maarten J

2010-01-01

Health economics provides a standardised methodology for valid comparisons of interventions in different fields of health care. This review discusses the health economic evaluations of strategies to enhance blood product safety in sub-Saharan Africa. We reviewed health economic methodology with special reference to cost-effectiveness analysis. We searched the literature for cost-effectiveness in blood product safety in sub-Saharan Africa. HIV-antibody screening in different settings in sub-Saharan Africa showed health gains and saved costs. Except for adding HIV-p24 screening, adding other tests such as nucleic acid amplification testing (NAT) to HIV-antibody screening displayed incremental cost-effectiveness ratios greater than the WHO/World Bank specified threshold for cost-effectiveness. The addition of HIV-p24 in combination with HCV antibody/antigen screening and multiplex (HBV, HCV and HIV) NAT in pools of 24 may also be cost-effective options for Ghana. From a health economic viewpoint, HIV-antibody screening should always be implemented in sub-Saharan Africa. The addition of HIV-p24 antigen screening, in combination with HCV antibody/antigen screening and multiplex (HBV, HCV and HIV) NAT in pools of 24 may be feasible options for Ghana. Suggestions for future health economic evaluations of blood transfusion safety interventions in sub-Saharan Africa are: mis-transfusion, laboratory quality and donor management. Copyright 2009 The International Association for Biologicals. Published by Elsevier Ltd. All rights reserved.

Antigen induced production of υ-interferon ex vivo, in the peripheral blood of patients with active pulmonary tuberculosis

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Z. M. Zagdyn

2013-01-01

Full Text Available Tuberculosis (TB is one of the most significant problems in the Russian Health Care. Russia remains on the list of the 22 countries with a high TB incidence and on the third place in the world with a high prevalence of Drug Resistant TB [1]. It is urgently needed to develop new TB diagnostic methods as well as effective measures of the specific TB prevention, including a development of the novel vaccines, so we have to know better about the most immunogenic antigens of Mycobacterium Tuberculosis. We studied the Interferon-Q production in the whole blood after stimulating immune response with different proteins of Mycobacterium Tuberculosis in patients with active TB. The study results permitted us to evaluate the immunogenicity of the previously known proteins (Ag85a и ESAT-6 in comparison to the recently identified ones (Rv2957, Rv2958c и Rv0447, analyzing simultaneously their relation to tuberculin, as well as to antigens of the different viruses (Human Immunodeficiency Virus, Cytomegalovirus, Epstein-Barr Virus, Influenza Virus. Protein Rv2958c, unlike protein ESAT-6, showed the high immunogenicity in comparison to tuberculin. The expressed immunogenicity of protein Rv2958c might be indicated a possible greatest specificity of immune response to this antigen in TB patients. Meanwhile, bacillary tuberculosis was strongly associated with low immune response to this protein. Also we were found statistical differences in immune responses of patients to the different Mycobacterium Tuberculosis antigens depending on the drug sensitivity. In addition it was interesting to know about a significantly low immune response of patients with Drug Resistant TB to protein pp65 CMV.

Optimizing HIV-1 protease production in Escherichia coli as fusion protein

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Piubelli Luciano

2011-06-01

Full Text Available Abstract Background Human immunodeficiency virus (HIV is the etiological agent in AIDS and related diseases. The aspartyl protease encoded by the 5' portion of the pol gene is responsible for proteolytic processing of the gag-pol polyprotein precursor to yield the mature capsid protein and the reverse transcriptase and integrase enzymes. The HIV protease (HIV-1Pr is considered an attractive target for designing inhibitors which could be used to tackle AIDS and therefore it is still the object of a number of investigations. Results A recombinant human immunodeficiency virus type 1 protease (HIV-1Pr was overexpressed in Escherichia coli cells as a fusion protein with bacterial periplasmic protein dithiol oxidase (DsbA or glutathione S-transferase (GST, also containing a six-histidine tag sequence. Protein expression was optimized by designing a suitable HIV-1Pr cDNA (for E. coli expression and to avoid autoproteolysis and by screening six different E. coli strains and five growth media. The best expression yields were achieved in E. coli BL21-Codon Plus(DE3-RIL host and in TB or M9 medium to which 1% (w/v glucose was added to minimize basal expression. Among the different parameters assayed, the presence of a buffer system (based on phosphate salts and a growth temperature of 37°C after adding IPTG played the main role in enhancing protease expression (up to 10 mg of chimeric DsbA:HIV-1Pr/L fermentation broth. GST:HIVPr was in part (50% produced as soluble protein while the overexpressed DsbA:HIV-1Pr chimeric protein largely accumulated in inclusion bodies as unprocessed fusion protein. A simple refolding procedure was developed on HiTrap Chelating column that yielded a refolded DsbA:HIV-1Pr with a > 80% recovery. Finally, enterokinase digestion of resolubilized DsbA:HIV-1Pr gave more than 2 mg of HIV-1Pr per liter of fermentation broth with a purity ≤ 80%, while PreScission protease cleavage of soluble GST:HIVPr yielded ~ 0.15 mg of pure HIV-1

HIV-1 vaccine-induced T-cell responses cluster in epitope hotspots that differ from those induced in natural infection with HIV-1.

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Hertz, Tomer; Ahmed, Hasan; Friedrich, David P; Casimiro, Danilo R; Self, Steven G; Corey, Lawrence; McElrath, M Juliana; Buchbinder, Susan; Horton, Helen; Frahm, Nicole; Robertson, Michael N; Graham, Barney S; Gilbert, Peter

2013-01-01

Several recent large clinical trials evaluated HIV vaccine candidates that were based on recombinant adenovirus serotype 5 (rAd-5) vectors expressing HIV-derived antigens. These vaccines primarily elicited T-cell responses, which are known to be critical for controlling HIV infection. In the current study, we present a meta-analysis of epitope mapping data from 177 participants in three clinical trials that tested two different HIV vaccines: MRKAd-5 HIV and VRC-HIVAD014-00VP. We characterized the population-level epitope responses in these trials by generating population-based epitope maps, and also designed such maps using a large cohort of 372 naturally infected individuals. We used these maps to address several questions: (1) Are vaccine-induced responses randomly distributed across vaccine inserts, or do they cluster into immunodominant epitope hotspots? (2) Are the immunodominance patterns observed for these two vaccines in three vaccine trials different from one another? (3) Do vaccine-induced hotspots overlap with epitope hotspots induced by chronic natural infection with HIV-1? (4) Do immunodominant hotspots target evolutionarily conserved regions of the HIV genome? (5) Can epitope prediction methods be used to identify these hotspots? We found that vaccine responses clustered into epitope hotspots in all three vaccine trials and some of these hotspots were not observed in chronic natural infection. We also found significant differences between the immunodominance patterns generated in each trial, even comparing two trials that tested the same vaccine in different populations. Some of the vaccine-induced immunodominant hotspots were located in highly variable regions of the HIV genome, and this was more evident for the MRKAd-5 HIV vaccine. Finally, we found that epitope prediction methods can partially predict the location of vaccine-induced epitope hotspots. Our findings have implications for vaccine design and suggest a framework by which different

Identification of dual-tropic HIV-1 using evolved neural networks.

Science.gov (United States)

Fogel, Gary B; Lamers, Susanna L; Liu, Enoch S; Salemi, Marco; McGrath, Michael S

2015-11-01

Blocking the binding of the envelope HIV-1 protein to immune cells is a popular concept for development of anti-HIV therapeutics. R5 HIV-1 binds CCR5, X4 HIV-1 binds CXCR4, and dual-tropic HIV-1 can bind either coreceptor for cellular entry. R5 viruses are associated with early infection and over time can evolve to X4 viruses that are associated with immune failure. Dual-tropic HIV-1 is less studied; however, it represents functional antigenic intermediates during the transition of R5 to X4 viruses. Viral tropism is linked partly to the HIV-1 envelope V3 domain, where the amino acid sequence helps dictate the receptor a particular virus will target; however, using V3 sequence information to identify dual-tropic HIV-1 isolates has remained difficult. Our goal in this study was to elucidate features of dual-tropic HIV-1 isolates that assist in the biological understanding of dual-tropism and develop an approach for their detection. Over 1559 HIV-1 subtype B sequences with known tropisms were analyzed. Each sequence was represented by 73 structural, biochemical and regional features. These features were provided to an evolved neural network classifier and evaluated using balanced and unbalanced data sets. The study resolved R5X4 viruses from R5 with an accuracy of 81.8% and from X4 with an accuracy of 78.8%. The approach also identified a set of V3 features (hydrophobicity, structural and polarity) that are associated with tropism transitions. The ability to distinguish R5X4 isolates will improve computational tropism decisions for R5 vs. X4 and assist in HIV-1 research and drug development efforts. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Mycoplasma fermentans glycolipid-antigen as a pathogen of rheumatoid arthritis

International Nuclear Information System (INIS)

Kawahito, Yutaka; Ichinose, Sizuko; Sano, Hajime; Tsubouchi, Yasunori; Kohno, Masataka; Yoshikawa, Toshikazu; Tokunaga, Daisaku; Hojo, Tatsuya; Harasawa, Ryo; Nakano, Teruaki; Matsuda, Kazuhiro

2008-01-01

Mycoplasma fermentans has been suspected as one of the causative pathogenic microorganisms of rheumatoid arthritis (RA) however, the pathogenic mechanism is still unclear. We, previously, reported that glycolipid-antigens (GGPL-I and III) are the major antigens of M. fermentans. Monoclonal antibody against the GGPL-III could detect the existence of the GGPL-III antigens in synovial tissues from RA patients. GGPL-III antigens were detected in 38.1% (32/84) of RA patient's tissues, but not in osteoarthritis (OA) and normal synovial tissues. Immunoelectron microscopy revealed that a part of GGPL-III antigens are located at endoplasmic reticulum. GGPL-III significantly induced TNF-α and IL-6 production from peripheral blood mononulear cells, and also proliferation of synovial fibroblasts. Further study is necessary to prove that M. fermentans is a causative microorganism of RA; however, the new mechanisms of disease pathogenesis provides hope for the development of effective and safe immunotherapeutic strategies based on the lipid-antigen, GGPL-III, in the near future

[Blood groups - minuses and pluses. Do the blood group antigens protect us from infectious diseases?].

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Czerwiński, Marcin

2015-06-25

Human blood can be divided into groups, which is a method of blood classification based on the presence or absence of inherited erythrocyte surface antigens that can elicit immune response. According to the International Society of Blood Transfusion, there are 341 blood group antigens collected in 35 blood group systems. These antigens can be proteins, glycoproteins or glycosphingolipids, and function as transmembrane transporters, ion channels, adhesion molecules or receptors for other proteins. The majority of blood group antigens is present also on another types of cells. Due to their localization on the surface of cells, blood group antigens can act as receptors for various pathogens or their toxins, such as protozoa (malaria parasites), bacteria (Helicobacter pylori, Vibrio cholerae and Shigella dysenteriae) and viruses (Noroviruses, Parvoviruses, HIV). If the presence of group antigen (or its variant which arised due to mutation) is beneficial for the host (e.g. because pathogens are not able to bind to the cells), the blood group may become a selection trait, leading to its dissemination in the population exposed to that pathogen. There are thirteen blood group systems that can be related to pathogen resistance, and it seems that the particular influence was elicit by malaria parasites. It is generally thought that the high incidence of blood groups such as O in the Amazon region, Fy(a-b-) in Africa and Ge(-) in Papua-New Guinea is the result of selective pressure from malaria parasite. This review summarizes the data about relationship between blood groups and resistance to pathogens.

Use of Recombinant Antigens for the Diagnosis of Invasive Candidiasis

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Ana Laín

2008-01-01

Full Text Available Invasive candidiasis is a frequent and often fatal complication in immunocompromised and critically ill patients. Unfortunately, the diagnosis of invasive candidiasis remains difficult due to the lack of specific clinical symptoms and a definitive diagnostic method. The detection of antibodies against different Candida antigens may help in the diagnosis. However, the methods traditionally used for the detection of antibodies have been based on crude antigenic fungal extracts, which usually show low-reproducibility and cross-reactivity problems. The development of molecular biology techniques has allowed the production of recombinant antigens which may help to solve these problems. In this review we will discuss the usefulness of recombinant antigens in the diagnosis of invasive candidiasis.

Heterologous Prime-Boost HIV-1 Vaccination Regimens in Pre-Clinical and Clinical Trials

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Julia L. Hurwitz

2010-02-01

Full Text Available Currently, there are more than 30 million people infected with HIV-1 and thousands more are infected each day. Vaccination is the single most effective mechanism for prevention of viral disease, and after more than 25 years of research, one vaccine has shown somewhat encouraging results in an advanced clinical efficacy trial. A modified intent-to-treat analysis of trial results showed that infection was approximately 30% lower in the vaccine group compared to the placebo group. The vaccine was administered using a heterologous prime-boost regimen in which both target antigens and delivery vehicles were changed during the course of inoculations. Here we examine the complexity of heterologous prime-boost immunizations. We show that the use of different delivery vehicles in prime and boost inoculations can help to avert the inhibitory effects caused by vector-specific immune responses. We also show that the introduction of new antigens into boost inoculations can be advantageous, demonstrating that the effect of ‘original antigenic sin’ is not absolute. Pre-clinical and clinical studies are reviewed, including our own work with a three-vector vaccination regimen using recombinant DNA, virus (Sendai virus or vaccinia virus and protein. Promising preliminary results suggest that the heterologous prime-boost strategy may possibly provide a foundation for the future prevention of HIV-1 infections in humans.

Elevated HLA-A expression impairs HIV control through inhibition of NKG2A-expressing cells.

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Ramsuran, Veron; Naranbhai, Vivek; Horowitz, Amir; Qi, Ying; Martin, Maureen P; Yuki, Yuko; Gao, Xiaojiang; Walker-Sperling, Victoria; Del Prete, Gregory Q; Schneider, Douglas K; Lifson, Jeffrey D; Fellay, Jacques; Deeks, Steven G; Martin, Jeffrey N; Goedert, James J; Wolinsky, Steven M; Michael, Nelson L; Kirk, Gregory D; Buchbinder, Susan; Haas, David; Ndung'u, Thumbi; Goulder, Philip; Parham, Peter; Walker, Bruce D; Carlson, Jonathan M; Carrington, Mary

2018-01-05

The highly polymorphic human leukocyte antigen ( HLA ) locus encodes cell surface proteins that are critical for immunity. HLA-A expression levels vary in an allele-dependent manner, diversifying allele-specific effects beyond peptide-binding preference. Analysis of 9763 HIV-infected individuals from 21 cohorts shows that higher HLA-A levels confer poorer control of HIV. Elevated HLA-A expression provides enhanced levels of an HLA-A-derived signal peptide that specifically binds and determines expression levels of HLA-E, the ligand for the inhibitory NKG2A natural killer (NK) cell receptor. HLA-B haplotypes that favor NKG2A-mediated NK cell licensing (i.e., education) exacerbate the deleterious effect of high HLA-A on HIV control, consistent with NKG2A-mediated inhibition impairing NK cell clearance of HIV-infected targets. Therapeutic blockade of HLA-E:NKG2A interaction may yield benefit in HIV disease. Copyright © 2017, American Association for the Advancement of Science.

The future of HIV prevention: prospects for an effective anti-HIV microbicide.

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Nuttall, Jeremy; Romano, Joseph; Douville, Karen; Galbreath, Caroline; Nel, Annaléne; Heyward, William; Mitchnick, Mark; Walker, Saul; Rosenberg, Zeda

2007-03-01

Topical microbicides are self-administered products for prevention of HIV transmission, and they present one of the most promising strategies for combating the HIV-AIDS epidemic. The development of microbicides is a long and complicated process, with many hurdles that are unique to this class of product, including challenges in product design, in the conduct and design of clinical trials, and in obtaining licensure of a new class of products intended for use almost exclusively in developing countries. Once they have been registered, there are additional challenges to the marketing and distribution of microbicides. An overview of the types of microbicide currently in development, and a summary of the issues and the approaches being taken to address them, are provided.

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...

Antigen dynamics of follicular dendritic cells

NARCIS (Netherlands)

Heesters, B.A.

2015-01-01

Stromal-derived follicular dendritic cells (FDCs) are a major depot for antigen that are essential for formation of germinal centers, the site where memory and effector B cells differentiate and high-affinity antibody production takes place. Historically, FDCs have been characterized as ‘accessory’

Human Tumor Antigens Yesterday, Today, and Tomorrow.

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Finn, Olivera J

2017-05-01

The question of whether human tumors express antigens that can be recognized by the immune system has been answered with a resounding YES. Most were identified through spontaneous antitumor humoral and cellular immune responses found in cancer patients and include peptides, glycopeptides, phosphopeptides, viral peptides, and peptides resulting from common mutations in oncogenes and tumor-suppressor genes, or common gene fusion events. Many have been extensively tested as candidates for anticancer vaccines. More recently, attention has been focused on the potentially large number of unique tumor antigens, mutated neoantigens, that are the predicted products of the numerous mutations revealed by exome sequencing of primary tumors. Only a few have been confirmed as targets of spontaneous immunity and immunosurveillance, and even fewer have been tested in preclinical and clinical settings. The field has been divided for a long time on the relative importance of shared versus mutated antigens in tumor surveillance and as candidates for vaccines. This question will eventually need to be answered in a head to head comparison in well-designed clinical trials. One advantage that shared antigens have over mutated antigens is their potential to be used in vaccines for primary cancer prevention. Cancer Immunol Res; 5(5); 347-54. ©2017 AACR . ©2017 American Association for Cancer Research.

Evaluation of an Antigen-Antibody

African Journals Online (AJOL)

GB

replication would lead to the production of various antigens. Today with BMT history of over 30 years, infection ... Study design: The study involved both retrospective and prospective laboratory-based analysis of ..... core protein of a molecular mass 19 x 103 Da, one picogram (pg) of virus core corresponds to 1.3 x. 105 HCV ...

Acute suppurative parotitis caused by Streptococcus pneumoniae in an HIV-infected man.

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Guzman Vinasco, Luis; Bares, Sara; Sandkovsky, Uriel

2015-03-02

We report a case of a 32-year-old man who presented with progressive unilateral parotid gland enlargement and subsequently tested positive for HIV. A CT scan of the neck performed with contrast showed a phlegmon in the region of the right parotid tail measuring approximately 2.5×2.4 cm. Cultures of the aspirated fluid grew Streptococcus pneumoniae and the S. pneumoniae urinary antigen test was also positive. The patient underwent surgical debridement and received antimicrobial therapy with complete resolution of the parotitis. Parotitis caused by S. pneumoniae is rare, and HIV infection should be suspected in any case of invasive pneumococcal disease. 2015 BMJ Publishing Group Ltd.

HIV vaccines: new frontiers in vaccine development.

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Duerr, Ann; Wasserheit, Judith N; Corey, Lawrence

2006-08-15

A human immunodeficiency virus (HIV) vaccine is the most promising and feasible strategy to prevent the events during acute infection that simultaneously set the course of the epidemic in the community and the course of the disease for the individual. Because safety concerns limit the use of live, attenuated HIV and inactivated HIV, a variety of alternate approaches is being investigated. Traditional antibody-mediated approaches using recombinant HIV envelope proteins have shown no efficacy in 2 phase III trials. Current HIV vaccine trials are focusing primarily on cytotoxic T lymphocyte-mediated products that use viral vectors, either alone or as boosts to DNA plasmids that contain viral genes. The most immunogenic of these products appear to be the recombinant adenovirus vector vaccines, 2 of which are now in advanced clinical development.

Quantification of oral palatine Langerhans cells in HIV/AIDS associated oral Kaposi sarcoma with and without oral candidiasis.

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Jivan, Vibha; Meer, Shabnum

2016-01-01

Langerhans cells (LCs) are effective antigen-presenting cells that function as "custodians" of mucosa, modifying the immune system to pathogen entry, and tolerance to self-antigen and commensal microbes. A reduction in number of LCs in human immunodeficiency virus (HIV)-positive individuals may predispose to local mucosal infections. To quantitatively determine the number of oral mucosal LCs in HIV/acquired immunodeficiency syndrome HIV/acquired immunodeficiency syndrome (AIDS) associated oral Kaposi sarcoma (KS) with/without oral candidiasis (OC) and to define in situ interrelationships between the cells, OC, and HIV infection. Thirty-two periodic acid-Schiff. (PAS) stained histologic sections of palatal HIV/AIDS associated KS with intact oral epithelium were examined for Candida and divided into two groups: . (1) KS coinfected with Candida and. (2) KS noninfected with Candida. Sections were immunohistochemically stained with CD1a. The standard length of surface epithelium was measured and number of positively stained LCs counted per unit length. Control cases included non-Candida infected palatal mucosa overlying pleomorphic adenoma. (PA) and oral mucosa infected with Candida in otherwise healthy individuals. LC number per unit length of surface epithelium was statistically significantly greatest in uninfected PA mucosa and lowest in KS coinfected with Candida (P = 0.0001). A statistically significant difference was also noted between uninfected PA mucosa and non-Candida infected KS (P = 0.0014), in KS coinfected with Candida and non-infected KS (P = 0.0035), between OC and PA (P = 0.0001), and OC and KS coinfected with Candida (P = 0.0247). LC numbers are significantly reduced in oral tissues of HIV/AIDS infected patients by Candida infection when compared to oral tissues without.

1,4-Bis(5-(naphthalen-1-yl)thiophen-2-yl)naphthalene, a small molecule, functions as a novel anti-HIV-1 inhibitor targeting the interaction between integrase and cellular Lens epithelium-derived growth factor.

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Gu, Wan-gang; Ip, Denis Tsz-Ming; Liu, Si-jie; Chan, Joseph H; Wang, Yan; Zhang, Xuan; Zheng, Yong-tang; Wan, David Chi-Cheong

2014-04-25

Translocation of viral integrase (IN) into the nucleus is a critical precondition of integration during the life cycle of HIV, a causative agent of Acquired Immunodeficiency Syndromes (AIDS). As the first discovered cellular factor to interact with IN, Lens epithelium-derived growth factor (LEDGF/p75) plays an important role in the process of integration. Disruption of the LEDGF/p75-IN interaction has provided a great interest for anti-HIV agent discovery. In this work, we reported that one small molecular compound, 1,4-bis(5-(naphthalen-1-yl)thiophen-2-yl)naphthalene(Compound 15), potently inhibit the IN-LEDGF/p75 interaction and affect the HIV-1 IN nuclear distribution at 1 μM. The putative binding mode of Compound 15 was constructed by a molecular docking simulation to provide structural insights into the ligand-binding mechanism. Compound 15 suppressed viral replication by measuring p24 antigen production in HIV-1IIIB acute infected C8166 cells with EC50 value of 11.19 μM. Compound 15 might supply useful structural information for further anti-HIV agent discovery. Copyright © 2014. Published by Elsevier Ireland Ltd.

Spontaneous release of soluble HL-A antigens from platelets during conservation.

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Dautigny, A; Bernier, I; Colombani, J; Jollès, P

1975-01-01

Experiments with the aim of studying the solubilisation of HL-A antigens from blood platelets by methods which do not involve any biologically active processes (moderate, discontinuous agitation of a low concentration of platelets suspended in a saline medium, in the presence of an antiseptic; supernatants collected at frequent intervals) have shown that platelets release membrane proteins, including HL-A antigens, spontaneously. Optimal conditions for the treatment of membrane proteins have been perfected. The great stability of HL-A antigens under these conditions permits prolonged treatment. The products extracted are soluble and extremely complex. The molecular weight of the HL-A antigens is between 40,000 and 70,000.

Chronic Hepatitis B and C Virus Infection and Risk for Non-Hodgkin Lymphoma in HIV-Infected Patients

DEFF Research Database (Denmark)

Wang, Qing; De Luca, Andrea; Smith, Colette

2017-01-01

Background: Non-Hodgkin lymphoma (NHL) is the most common AIDS-defining condition in the era of antiretroviral therapy (ART). Whether chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infection promote NHL in HIV-infected patients is unclear. Objective: To investigate whether chronic HBV...... and HCV infection are associated with increased incidence of NHL in HIV-infected patients. Design: Cohort study. Setting: 18 of 33 cohorts from the Collaboration of Observational HIV Epidemiological Research Europe (COHERE). Patients: HIV-infected patients with information on HBV surface antigen...... measurements and detectable HCV RNA, or a positive HCV antibody test result if HCV RNA measurements were not available. Measurements: Time-dependent Cox models to assess risk for NHL in treatment-naive patients and those initiating ART, with inverse probability weighting to control for informative censoring...

HIV awareness and condom use among female sex workers in Afghanistan: implications for intervention.

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Todd, Catherine S; Nasir, Abdul; Stanekzai, Mohammad R; Scott, Paul T; Close, Nicole C; Botros, Boulos A; Strathdee, Steffanie A; Tjaden, Jeffrey

2011-03-01

There is little information about HIV awareness or condom use among female sex workers (FSWs) in Afghanistan. The purpose of this cross-sectional study was to assess HIV awareness, knowledge, and condom use among FSWs in three Afghan cities. FSWs residing in Jalalabad, Kabul, and Mazar-i-Sharif were recruited through outreach programs and completed an interviewer-administered questionnaire and rapid tests for hepatitis B surface antigen, HIV, syphilis, and hepatitis C virus. Logistic regression identified factors associated with HIV awareness, comprehensive HIV knowledge (knowledge that HIV cannot be detected by sight, that condoms prevent HIV, and rejection of local misconceptions about HIV transmission), and consistent condom use (use with every sex act) with clients in the last six months. Of 520 participants, 76.9% had no formal education and 37.7% lived outside Afghanistan in the last five years. Nearly half (44.2%) were aware of HIV but, of these, only 17.4% (N = 40) had comprehensive HIV knowledge. There were significant differences by site; FSWs in Jalalabad were more likely to be aware of HIV but FSWs in Kabul were more likely to have correct HIV knowledge and use condoms consistently with clients. Consistent client condom use was reported by 11.5% (N = 60) and was independently associated with having more clients per month (AOR = 1.99, 95% CI: 1.04-3.81). In conclusion, comprehensive HIV knowledge and consistent condom use with clients are low among Afghan FSWs in these cities. Efforts to reach this population should focus on relaying accurate information and expanding condom use with clients.

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.

Opt-Out Panel Testing for HIV, Hepatitis B and Hepatitis C in an Urban Emergency Department: A Pilot Study.

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Sarah O'Connell

Full Text Available Studies suggest 2 per 1000 people in Dublin are living with HIV, the level above which universal screening is advised. We aimed to assess the feasibility and acceptability of a universal opt-out HIV, Hepatitis B and Hepatitis C testing programme for Emergency Department patients and to describe the incidence and prevalence of blood-borne viruses in this population.An opt-out ED blood borne virus screening programme was piloted from March 2014 to January 2015. Patients undergoing blood sampling during routine clinical care were offered HIV 1&2 antibody/antigen assay, HBV surface antigen and HCV antibody tests. Linkage to care where necessary was co-ordinated by the study team. New diagnosis and prevalence rates were defined as the new cases per 1000 tested and number of positive tests per 1000 tested respectively.Over 45 weeks of testing, of 10,000 patient visits, 8,839 individual patient samples were available for analysis following removal of duplicates. A sustained target uptake of >50% was obtained after week 3. 97(1.09%, 44(0.49% and 447(5.05% HIV, Hepatitis B and Hepatitis C tests were positive respectively. Of these, 7(0.08%, 20(0.22% and 58(0.66% were new diagnoses of HIV, Hepatitis B and Hepatitis C respectively. The new diagnosis rate for HIV, Hepatitis B and Hepatitis C was 0.8, 2.26 and 6.5 per 1000 and study prevalence for HIV, Hepatitis B and Hepatitis C was 11.0, 5.0 and 50.5 per 1000 respectively.Opt-out blood borne viral screening was feasible and acceptable in an inner-city ED. Blood borne viral infections were prevalent in this population and newly diagnosed cases were diagnosed and linked to care. These results suggest widespread blood borne viral testing in differing clinical locations with differing population demographic risks may be warranted.

Identification of immunogenic HLA-B7 "Achilles' heel" epitopes within highly conserved regions of HIV

DEFF Research Database (Denmark)

De Groot, Anne S; Rivera, Daniel S; McMurry, Julie A

2008-01-01

Genetic polymorphisms in class I human leukocyte antigen molecules (HLA) have been shown to determine susceptibility to HIV infection as well as the rate of progression to AIDS. In particular, the HLA-B7 supertype has been shown to be associated with high viral loads and rapid progression to dise...

Cysteine mutagenesis improves the production without abrogating antigenicity of a recombinant protein vaccine candidate for human chagas disease.

Science.gov (United States)

Seid, Christopher A; Jones, Kathryn M; Pollet, Jeroen; Keegan, Brian; Hudspeth, Elissa; Hammond, Molly; Wei, Junfei; McAtee, C Patrick; Versteeg, Leroy; Gutierrez, Amanda; Liu, Zhuyun; Zhan, Bin; Respress, Jonathan L; Strych, Ulrich; Bottazzi, Maria Elena; Hotez, Peter J

2017-03-04

A therapeutic vaccine for human Chagas disease is under development by the Sabin Vaccine Institute Product Development Partnership. The aim of the vaccine is to significantly reduce the parasite burden of Trypanosoma cruzi in humans, either as a standalone product or in combination with conventional chemotherapy. Vaccination of mice with Tc24 formulated with monophosphoryl-lipid A (MPLA) adjuvant results in a Th1 skewed immune response with elevated IgG2a and IFNγ levels and a statistically significant decrease in parasitemia following T. cruzi challenge. Tc24 was therefore selected for scale-up and further evaluation. During scale up and downstream process development, significant protein aggregation was observed due to intermolecular disulfide bond formation. To prevent protein aggregation, cysteine codons were replaced with serine codons which resulted in the production of a non-aggregated and soluble recombinant protein, Tc24-C4. No changes to the secondary structure of the modified molecule were detected by circular dichroism. Immunization of mice with wild-type Tc24 or Tc24-C4, formulated with E6020 (TLR4 agonist analog to MPLA) emulsified in a squalene-oil-in-water emulsion, resulted in IgG2a and antigen specific IFNγ production levels from splenocytes that were not significantly different, indicating that eliminating putative intermolecular disulfide bonds had no significant impact on the immunogenicity of the molecule. In addition, vaccination with either formulated wild type Tc24 or Tc24-C4 antigen also significantly increased survival and reduced cardiac parasite burden in mice. Investigations are now underway to examine the efficacy of Tc24-C4 formulated with other adjuvants to reduce parasite burden and increase survival in pre-clinical studies.

Constitutively Active MAVS Inhibits HIV-1 Replication via Type I Interferon Secretion and Induction of HIV-1 Restriction Factors.

Directory of Open Access Journals (Sweden)

Sachin Gupta

Full Text Available Type I interferon is known to inhibit HIV-1 replication through the induction of interferon stimulated genes (ISG, including a number of HIV-1 restriction factors. To better understand interferon-mediated HIV-1 restriction, we constructed a constitutively active form of the RIG-I adapter protein MAVS. Constitutive MAVS was generated by fusion of full length MAVS to a truncated form of the Epstein Barr virus protein LMP1 (ΔLMP1. Supernatant from ΔLMP1-MAVS-transfected 293T cells contained high levels of type I interferons and inhibited HIV replication in both TZM-bl and primary human CD4+ T cells. Supernatant from ΔLMP1-MAVS-transfected 293T cells also inhibited replication of VSV-G pseudotyped single cycle SIV in TZM-bl cells, suggesting restriction was post-entry and common to both HIV and SIV. Gene array analysis of ΔLMP1-MAVS-transfected 293T cells and trans-activated CD4+ T cells showed significant upregulation of ISG, including previously characterized HIV restriction factors Viperin, Tetherin, MxB, and ISG56. Interferon blockade studies implicated interferon-beta in this response. In addition to direct viral inhibition, ΔLMP1-MAVS markedly enhanced secretion of IFN-β and IL-12p70 by dendritic cells and the activation and maturation of dendritic cells. Based on this immunostimulatory activity, an adenoviral vector (Ad5 expressing ΔLMP1-MAVS was tested as a molecular adjuvant in an HIV vaccine mouse model. Ad5-Gag antigen combined with Ad5-ΔLMP1-MAVS enhanced control of vaccinia-gag replication in a mouse challenge model, with 4/5 animals showing undetectable virus following challenge. Overall, ΔLMP1-MAVS is a promising reagent to inhibit HIV-1 replication in infected tissues and enhance vaccine-mediated immune responses, while avoiding toxicity associated with systemic type I interferon administration.

T lymphocytes from irradiation chimeras repopulated with 13-day fetal liver cells recognize antigens only in association with self-MHC products

International Nuclear Information System (INIS)

Nisbet-Brown, E.; Diener, E.

1986-01-01

The restriction specificities of maturing thymocytes are determined by the Class II MHC antigens expressed by non-lymphoid thymic tissues. The proliferative response of mature T lymphocytes to antigen-presenting cells (APC) and antigen requires that the APC express the same MHC antigens as the thymus in which the T cells differentiated. Thus, in the two-way bone marrow chimera [A + B----(A x B)F1], T lymphocyte populations of A and B haplotypes have each acquired the potential to recognize antigens associated with either parental haplotype. In spite of the large body of work on MHC restriction, we still do not have a clear understanding of the mechanisms which impose self restriction. The chimeric model systems used previously to study MHC restriction have used adult bone marrow cells as the source of lymphoid precursors. During normal ontogeny, T cells are derived from precursors in the fetal liver and we felt that a direct comparison of T cells from fetal liver and bone marrow-repopulated animals would shed light on the development of MHC restriction specificities during T cell ontogeny in the thymus or prethymically. We found that parental T lymphocyte populations isolated from two-way fetal liver chimeras cooperated only with syngeneic APC, while those from bone marrow chimeras cooperated with APC of either parental haplotype. This suggests that fetal liver and bone marrow may not be equivalent sources of stem cells. Our results may be due to fundamental differences between thymocyte precursors in fetal liver and bone marrow, including the time course of their expression of T cell receptor gene products

Growth, productivity, and scientific impact of sources of HIV/AIDS ...

African Journals Online (AJOL)

As channels of communicating HIV/AIDS research information, serial publications and particularly journals are increasingly used in response to the pandemic. The last few decades have witnessed a proliferation of sources of HIV/AIDS-related information, bringing many challenges to collection-development librarians as ...

Ubiquitinated Proteins Isolated From Tumor Cells Are Efficient Substrates for Antigen Cross-Presentation.

Science.gov (United States)

Yu, Guangjie; Moudgil, Tarsem; Cui, Zhihua; Mou, Yongbin; Wang, Lixin; Fox, Bernard A; Hu, Hong-Ming

2017-06-01

We have previously shown that inhibition of the proteasome causes defective ribosomal products to be shunted into autophagosomes and subsequently released from tumor cells as defective ribosomal products in Blebs (DRibbles). These DRibbles serve as an excellent source of antigens for cross-priming of tumor-specific T cells. Here, we examine the role of ubiquitinated proteins (Ub-proteins) in this pathway. Using purified Ub-proteins from tumor cells that express endogenous tumor-associated antigen or exogenous viral antigen, we tested the ability of these proteins to stimulate antigen-specific T-cell responses, by activation of monocyte-derived dendritic cells generated from human peripheral blood mononuclear cells. Compared with total cell lysates, we found that purified Ub-proteins from both a gp100-specific melanoma cell line and from a lung cancer cell line expressing cytomegalovirus pp65 antigen produced a significantly higher level of IFN-γ in gp100- or pp65-specific T cells, respectively. In addition, Ub-proteins from an allogeneic tumor cell line could be used to stimulate tumor-infiltrating lymphocytes isolated and expanded from non-small cell lung cancer patients. These results establish that Ub-proteins provide a relevant source of antigens for cross-priming of antitumor immune responses in a variety of settings, including endogenous melanoma and exogenous viral antigen presentation, as well as antigen-specific tumor-infiltrating lymphocytes. Thus, ubiquitin can be used as an affinity tag to enrich for unknown tumor-specific antigens from tumor cell lysates to stimulate tumor-specific T cells ex vivo or to be used as vaccines to target short-lived proteins.

Lymphocyte trafficking and HIV infection of human lymphoid tissue in a rotating wall vessel bioreactor

Science.gov (United States)

Margolis, L. B.; Fitzgerald, W.; Glushakova, S.; Hatfill, S.; Amichay, N.; Baibakov, B.; Zimmerberg, J.

1997-01-01

The pathogenesis of HIV infection involves a complex interplay between both the infected and noninfected cells of human lymphoid tissue, the release of free viral particles, the de novo infection of cells, and the recirculatory trafficking of peripheral blood lymphocytes. To develop an in vitro model for studying these various aspects of HIV pathogenesis we have utilized blocks of surgically excised human tonsils and a rotating wall vessel (RWV) cell culture system. Here we show that (1) fragments of the surgically excised human lymphoid tissue remain viable and retain their gross cytoarchitecture for at least 3 weeks when cultured in the RWV system; (2) such lymphoid tissue gradually shows a loss of both T and B cells to the surrounding growth medium; however, this cellular migration is reversible as demonstrated by repopulation of the tissue by labeled cells from the growth medium; (3) this cellular migration may be partially or completely inhibited by embedding the blocks of lymphoid tissue in either a collagen or agarose gel matrix; these embedded tissue blocks retain most of the basic elements of a normal lymphoid cytoarchitecture; and (4) both embedded and nonembedded RWV-cultured blocks of human lymphoid tissue are capable of productive infection by HIV-1 of at least three various strains of different tropism and phenotype, as shown by an increase in both p24 antigen levels and free virus in the culture medium, and by the demonstration of HIV-1 RNA-positive cells inside the tissue identified by in situ hybridization. It is therefore reasonable to suggest that gel-embedded and nonembedded blocks of human lymphoid tissue, cocultured with a suspension of tonsillar lymphocytes in an RWV culture system, constitute a useful model for simulating normal lymphocyte recirculatory traffic and provide a new tool for testing the various aspects of HIV pathogenesis.

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.

Safety and Immunogenicity of a Recombinant Adenovirus Serotype 35-Vectored HIV-1 Vaccine in Adenovirus Serotype 5 Seronegative and Seropositive Individuals.

Science.gov (United States)

Fuchs, Jonathan D; Bart, Pierre-Alexandre; Frahm, Nicole; Morgan, Cecilia; Gilbert, Peter B; Kochar, Nidhi; DeRosa, Stephen C; Tomaras, Georgia D; Wagner, Theresa M; Baden, Lindsey R; Koblin, Beryl A; Rouphael, Nadine G; Kalams, Spyros A; Keefer, Michael C; Goepfert, Paul A; Sobieszczyk, Magdalena E; Mayer, Kenneth H; Swann, Edith; Liao, Hua-Xin; Haynes, Barton F; Graham, Barney S; McElrath, M Juliana

2015-05-01

Recombinant adenovirus serotype 5 (rAd5)-vectored HIV-1 vaccines have not prevented HIV-1 infection or disease and pre-existing Ad5 neutralizing antibodies may limit the clinical utility of Ad5 vectors globally. Using a rare Ad serotype vector, such as Ad35, may circumvent these issues, but there are few data on the safety and immunogenicity of rAd35 directly compared to rAd5 following human vaccination. HVTN 077 randomized 192 healthy, HIV-uninfected participants into one of four HIV-1 vaccine/placebo groups: rAd35/rAd5, DNA/rAd5, and DNA/rAd35 in Ad5-seronegative persons; and DNA/rAd35 in Ad5-seropositive persons. All vaccines encoded the HIV-1 EnvA antigen. Antibody and T-cell responses were measured 4 weeks post boost immunization. All vaccines were generally well tolerated and similarly immunogenic. As compared to rAd5, rAd35 was equally potent in boosting HIV-1-specific humoral and cellular immunity and responses were not significantly attenuated in those with baseline Ad5 seropositivity. Like DNA, rAd35 efficiently primed rAd5 boosting. All vaccine regimens tested elicited cross-clade antibody responses, including Env V1/V2-specific IgG responses. Vaccine antigen delivery by rAd35 is well-tolerated and immunogenic as a prime to rAd5 immunization and as a boost to prior DNA immunization with the homologous insert. Further development of rAd35-vectored prime-boost vaccine regimens is warranted.

Maturation and Mip-1β Production of Cytomegalovirus-Specific T Cell Responses in Tanzanian Children, Adolescents and Adults: Impact by HIV and Mycobacterium tuberculosis Co-Infections.

Directory of Open Access Journals (Sweden)

Damien Portevin

Full Text Available It is well accepted that aging and HIV infection are associated with quantitative and functional changes of CMV-specific T cell responses. We studied here the expression of Mip-1β and the T cell maturation marker CD27 within CMVpp65-specific CD4(+ and CD8(+ T cells in relation to age, HIV and active Tuberculosis (TB co-infection in a cohort of Tanzanian volunteers (≤ 16 years of age, n = 108 and ≥ 18 years, n = 79. Independent of HIV co-infection, IFNγ(+ CMVpp65-specific CD4(+ T cell frequencies increased with age. In adults, HIV co-infection further increased the frequencies of these cells. A high capacity for Mip-1β production together with a CD27(low phenotype was characteristic for these cells in children and adults. Interestingly, in addition to HIV co-infection active TB disease was linked to further down regulation of CD27 and increased capacity of Mip-1β production in CMVpp65-specific CD4+ T cells. These phenotypic and functional changes of CMVpp65-specific CD4 T cells observed during HIV infection and active TB could be associated with increased CMV reactivation rates.

Management of HIV disease in China.

Science.gov (United States)

Li, D L

1991-01-01

This brief report is concerned with the management of HIV infection since the 1980's in China. Mention was made of the 2-day Sino/American Symposium on Management of HIV Disease held in Beijing in 1990. Attendance included 600 participants from China and the US. 40 experts presented papers on topics covering diagnosis, treatment, research, prevention, psychology, sociology, ethics, education, and law. The Chinese Minister of Public Health and President of the Chinese Medical Association urged a unified and multiregional and multinational effort and a global network to combat HIV disease. Since the 1980's the Chinese government has instituted measures of prevention and control and recognized the harmful effects to health and life. Since 1985, 300,000 of the high risk population have received blood serum tests, of which 446 were found to be HIV positive. 5 were AIDS patients, of which 3 were foreigners and the other 2 from Beijing and Yunnan Province (southwest region) respectively. Included in the HIV positive group were 68 foreigners and 378 mainland Chinese. There have been no reported cases of mother/child infection. Drug users are identified as the high risk group for contracting and spreading the HIV infection. The number of drug users has increased rapidly, particularly along border regions of the southwest, and the method of use has been identified as intravenous injection. AIDS is now considered by the Chinese government as an infectious disease. There are monitoring stations in almost all provinces. The Ministry of Public Health has 3 laboratories for diagnosis of the HIV virus. A strain of HIV-1 virus has been isolated from a foreign tourist and used to prepare a diagnostic antigen. 5 units currently have P--grade laboratories for researching the etiology and molecular biology of AIDS. Research in medical institutes is also progressing on the use of traditional Chinese medicine to treat AIDS. Cooperation between China and the World Health Organization has

A Directed Molecular Evolution Approach to Improved Immunogenicity of the HIV-1 Envelope Glycoprotein

Science.gov (United States)

Du, Sean X.; Xu, Li; Zhang, Wenge; Tang, Susan; Boenig, Rebecca I.; Chen, Helen; Mariano, Ellaine B.; Zwick, Michael B.; Parren, Paul W. H. I.; Burton, Dennis R.; Wrin, Terri; Petropoulos, Christos J.; Ballantyne, John A.; Chambers, Michael; Whalen, Robert G.

2011-01-01

A prophylactic vaccine is needed to slow the spread of HIV-1 infection. Optimization of the wild-type envelope glycoproteins to create immunogens that can elicit effective neutralizing antibodies is a high priority. Starting with ten genes encoding subtype B HIV-1 gp120 envelope glycoproteins and using in vitro homologous DNA recombination, we created chimeric gp120 variants that were screened for their ability to bind neutralizing monoclonal antibodies. Hundreds of variants were identified with novel antigenic phenotypes that exhibit considerable sequence diversity. Immunization of rabbits with these gp120 variants demonstrated that the majority can induce neutralizing antibodies to HIV-1. One novel variant, called ST-008, induced significantly improved neutralizing antibody responses when assayed against a large panel of primary HIV-1 isolates. Further study of various deletion constructs of ST-008 showed that the enhanced immunogenicity results from a combination of effective DNA priming, an enhanced V3-based response, and an improved response to the constant backbone sequences. PMID:21738594

[Synthesis of protective antigens during submerged cultivation of Vibrio cholerae].

Science.gov (United States)

Fedorova, V A; Syrova, N A; Gromova, O V; Tershkina, N E; Devdariani, Z L; Dzhaparidze, M N; Meleshchenko, M V; Dobrova, G V; Beliakova, N I; Ermakov, N M; Eliseev, Iu Iu

2000-01-01

The effectiveness of dot immunoanalysis for evaluating the dynamics of the synthesis of O-antigen, cholera toxin, neuraminidase, adhesin CFA1 in the process of the reactor cultivation of V. cholerae used for the production of oral chemical cholera vaccine is shown. The established regularities of the synthesis of the protective antigens of V. cholerae in the process of scaled-up cultivation are discussed.

Characterization of HIV-Specific CD4+T Cell Responses against Peptides Selected with Broad Population and Pathogen Coverage

DEFF Research Database (Denmark)

Buggert, Marcus; Norstrom, Melissa M.; Czarnecki, Chris

2012-01-01

for the identification of HIV-specific CD4+ T cells targeting broadly reactive epitopes in populations with diverse ethnic background stems from the vast genomic variation of HIV and the diversity of the host cellular immune system. Here, we describe a novel epitope selection strategy, PopCover, that aims to resolve...... this challenge, and identify a set of potential HLA class II-restricted HIV epitopes that in concert will provide optimal viral and host coverage. Using this selection strategy, we identified 64 putative epitopes (peptides) located in the Gag, Nef, Env, Pol and Tat protein regions of HIV. In total, 73...... II-restricted epitopes. All together, selection strategies, such as PopCover, might with success be used for the evaluation of antigen-specific CD4+ T cell responses and design of future vaccines....

Toll-Like Receptor 2 Ligation Enhances HIV-1 Replication in Activated CCR6+ CD4+ T Cells by Increasing Virus Entry and Establishing a More Permissive Environment to Infection.

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Bolduc, Jean-François; Ouellet, Michel; Hany, Laurent; Tremblay, Michel J

2017-02-15

In this study, we investigated the effect of Toll-like receptor 2 (TLR2) ligation on the permissiveness of activated CD4 + T cells to HIV-1 infection by focusing our experiments on the relative susceptibility of cell subsets based on their expression of CCR6. Purified primary human CD4 + T cells were first subjected to a CD3/CD28 costimulation before treatment with the TLR2 agonist Pam3CSK4. Finally, cells were inoculated with R5-tropic HIV-1 particles that permit us to study the effect of TLR2 triggering on virus production at both population and single-cell levels. We report here that HIV-1 replication is augmented in CD3/CD28-costimulated CCR6 + CD4 + T cells upon engagement of the cell surface TLR2. Additional studies indicate that a higher virus entry and polymerization of the cortical actin are seen in this cell subset following TLR2 stimulation. A TLR2-mediated increase in the level of phosphorylated NF-κB p65 subunit was also detected in CD3/CD28-costimulated CCR6 + CD4 + T cells. We propose that, upon antigenic presentation, an engagement of TLR2 acts specifically on CCR6 + CD4 + T cells by promoting virus entry in an intracellular milieu more favorable for productive HIV-1 infection. Following primary infection, HIV-1 induces an immunological and structural disruption of the gut mucosa, leading to bacterial translocation and release of microbial components in the bloodstream. These pathogen-derived constituents include several agonists of Toll-like receptors that may affect gut-homing CD4 + T cells, such as those expressing the chemokine receptor CCR6, which are highly permissive to HIV-1 infection. We demonstrate that TLR2 ligation in CD3/CD28-costimulated CCR6 + CD4 + T cells leads to enhanced virus production. Our results highlight the potential impact of bacterial translocation on the overall permissiveness of CCR6 + CD4 + T cells to productive HIV-1 infection. Copyright © 2017 American Society for Microbiology.

Viral-Associated GN: Hepatitis C and HIV.

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Kupin, Warren L

2017-08-07

Viruses are capable of inducing a wide spectrum of glomerular disorders that can be categorized on the basis of the duration of active viremia: acute, subacute, or chronic. The variable responses of the adaptive immune system to each time period of viral infection results mechanistically in different histologic forms of glomerular injury. The unique presence of a chronic viremic carrier state with either hepatitis C (HCV) or HIV has led to the opportunity to study in detail various pathogenic mechanisms of viral-induced glomerular injury, including direct viral infection of renal tissue and the development of circulating immune complexes composed of viral antigens that deposit along the glomerular basement membrane. Epidemiologic data show that approximately 25%-30% of all HIV patients are coinfected with HCV and 5%-10% of all HCV patients are coinfected with HIV. This situation can often lead to a challenging differential diagnosis when glomerular disease occurs in this dual-infected population and requires the clinician to be familiar with the clinical presentation, laboratory workup, and pathophysiology behind the development of renal disease for both HCV and HIV. Both of these viruses can be categorized under the new classification of infection-associated GN as opposed to being listed as causes of postinfectious GN as has previously been applied to them. Neither of these viruses lead to renal injury after a latent period of controlled and inactive viremia. The geneses of HCV- and HIV-associated glomerular diseases share a total dependence on the presence of active viral replication to sustain renal injury so the renal disease cannot be listed under "postinfectious" GN. With the new availability of direct-acting antivirals for HCV and more effective combined antiretroviral therapy for HIV, successful remission and even regression of glomerular lesions can be achieved if initiated at an early stage. Copyright © 2017 by the American Society of Nephrology.

Gender Relations and the Production of Difference in School-based Sexuality and HIV/AIDS Education in Australia.

Science.gov (United States)

Harrison, Lyn

2000-01-01

Uses data from an evaluation of a high school sexuality education program to examine gender relations and production of difference. Participating schools incorporated teaching and learning that normalized sexual diversity and explored HIV-related discrimination and homophobia. Discussion of gender, power, and menstruation and heterosexism and…

Real-time PCR analysis of genes encoding tumor antigens in esophageal tumors and a cancer vaccine

DEFF Research Database (Denmark)

Weinert, Brian T; Krishnadath, Kausilia K; Milano, Francesca

2009-01-01

Tumor antigens are the primary target of therapeutic cancer vaccines. We set out to define and compare the expression pattern of tumor antigen genes in esophagus carcinoma biopsies and in an allogeneic tumor lysate-based cancer vaccine, MelCancerVac. Cells used for vaccine production were treated...... in the production of the vaccine. Quantitative PCR was used to assay 74 tumor antigen genes in patients with squamous cell carcinoma of the esophagus. 81% (13/16) of tumors expressed more than five cancer/testis (CT) antigens. A total of 96 genes were assayed in the tumor cell clone (DDM1.7) used to make tumor cell...

Longitudinal dynamics of the HIV-specific B cell response during intermittent treatment of primary HIV infection.

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Godelieve J de Bree

Full Text Available Neutralizing antibodies develop in natural HIV-1 infection. Their development often takes several years and may rely on chronic virus exposure. At the same time recent studies show that treatment early in infection may provide opportunities for immune preservation. However, it is unknown how intermittent treatment in early infection affects development of the humoral immune response over time. We investigate the effect of cART in early HIV infection on the properties of the memory B cell compartment following 6 months of cART or in the absence of treatment. The patients included participated in the Primo-SHM trial where patients with an early HIV-1 infection were randomized to no treatment or treatment for 24 or 60 weeks.Primo-SHM trial patients selected for the present study were untreated (n = 23 or treated for 24 weeks (n = 24. Here we investigate memory B cell properties at viral set-point and at a late time point (respectively median 54 and 73 weeks before (re-initiation of treatment.At viral set-point, the memory B cell compartment in treated patients demonstrated significantly lower fractions of antigen-primed, activated, memory B cells (p = 0.006. In contrast to untreated patients, in treated patients the humoral HIV-specific response reached a set point over time. At a transcriptional level, sets of genes that showed enhanced expression in memory B cells at viral setpoint in untreated patients, conversely showed rapid increase of expression of the same genes in treated patients at the late time point.These data suggest that, although the memory B cell compartment is phenotypically preserved until viral setpoint after treatment interruption, the development of the HIV-specific antibody response may benefit from exposure to HIV. The effect of viral exposure on B cell properties is also reflected by longitudinal changes in transcriptional profile in memory B cells over time in early treated patients.

Dichotomy of the human T cell response to Leishmania antigens. I. Th1-like response to Leishmania major promastigote antigens in individuals recovered from cutaneous leishmaniasis

DEFF Research Database (Denmark)

Kemp, M; Hey, A S; Kurtzhals, J A

1994-01-01

of skin lesions, and in Danes without known exposure to Leishmania parasites. Proliferation and production of interferon-gamma (IFN-gamma) and IL-4 in antigen-stimulated cultures was measured. Lymphocytes from individuals with a history of CL proliferated vigorously and produced IFN-gamma after...... the unexposed Danes were not activated by gp63. The cells from Danish donors produced either IFN-gamma or IL-4, but not both cytokines after incubation with the crude preparation of L. major antigens. The data show that the T cell response to Leishmania antigens in humans who have had uncomplicated CL...... stimulation with either a crude preparation of L. major antigens or the major surface protease gp63. These cultures produced no or only little IL-4. Also cells from leishmanin skin test-positive donors with no history of CL produced IFN-gamma and no IL-4 in response to L. major antigens. Cells from...

No difference in in vitro susceptibility to HIV type 1 between high-risk HIV-negative Ethiopian commercial sex workers and low-risk control subjects

NARCIS (Netherlands)

Messele, T.; Rinke de Wit, T. F.; Brouwer, M.; Aklilu, M.; Birru, T.; Fontanet, A. L.; Schuitemaker, H.; Hamann, D.

2001-01-01

Host factors such as increased beta-chemokine production, HIV-1 coreceptor expression level, and HIV-1 coreceptor polymorphism have been thought to influence susceptibility to HIV-1 infection. To determine the protective role of these factors in Ethiopians who remained HIV-1 uninfected, despite

Determination of Immunogenic Relevant Antigens in the Excretory-Secretory (ES Products and the Lysates of Ascaridia galli Larvae

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S Saffi

2008-04-01

Full Text Available Background: Ascaridia galli, the largest nematode of small intestine of birds, especially the native poultry, may give rise to serious illness, pathological defects and economical losses even in modern poultry production systems. Although various measures have been undertaken to vaccinate poultry against A.galli, no satisfactory results were obtained so far. However, there is no report on the efficacy of excretory-secretory (ES proteins of A.galli larvae in immunization of poultry. Thus, the aim of the present research project was based on the use of the ES products of the larvae, in order to find the protective anti­gens.Methods: Five hundred native poultry were autopsied and adult A.galli was removed form their intestines. The eggs were harvested form the uterus of female worms and cultured at 25 ˚C in water containing 0.1 N sulphuric acid for almost a fort­night. The larvae were then freed mechanically and kept in Earl's salt solution for a few days. The supernatant solution of alive larvae containing the ES products of the larvae, as well as the sonicated alive and dead larvae, was analyzed by SDS-PAGE.Result: Many protein fractions of 15 kDa up to 200 kDa were demonstrated in lysate of these larvae. Using the serum of a hen, infected with a high numbers of A.galli, an immunogenic antigen was identified between 55 kDa to 72 kDa by Western blotting procedure.Conclusion: Finding the protein band between 55 and 72 kDa can be promising for preparation of vaccine, though more investigations are needed to prove the protective ability of this antigen.

Pancreatic involvement in co-infection visceral leishmaniasis and HIV: histological and ultrastructural aspects

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CHEHTER Ethel Zimberg

2001-01-01

Full Text Available The involvement of the gastrointestinal tract in the co-infection of HIV and Leishmania is rarely reported. We report the case of an HIV-infected adult man co-infected with a disseminated form of leishmaniasis involving the liver, lymph nodes, spleen and, as a feature reported for the first time in the English literature, the pancreas. Light microscopy showed amastigote forms of Leishmania in pancreatic macrophages and immunohistochemical staining revealed antigens for Leishmania and also for HIV p24. Microscopic and ultrastructural analysis revealed severe acinar atrophy, decreased zymogen granules in the acinar cytoplasm and also nuclear abnormalities such as pyknosis, hyperchromatism and thickened chromatin. These findings might correspond to the histologic pattern of protein-energy malnutrition in the pancreas as shown in our previous study in pancreas with AIDS and no Leishmania. In this particular case, the protein-energy malnutrition may be due to cirrhosis, or, Leishmania or HIV infection or all mixed. We believe that this case represents the morphologic substratum of the protein energy malnutrition in pancreas induced by the HIV infection. Further studies are needed to elucidate these issues.

EASY-HIT: HIV full-replication technology for broad discovery of multiple classes of HIV inhibitors.

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Kremb, Stephan; Helfer, Markus; Heller, Werner; Hoffmann, Dieter; Wolff, Horst; Kleinschmidt, Andrea; Cepok, Sabine; Hemmer, Bernhard; Durner, Jörg; Brack-Werner, Ruth

2010-12-01

HIV replication assays are important tools for HIV drug discovery efforts. Here, we present a full HIV replication system (EASY-HIT) for the identification and analysis of HIV inhibitors. This technology is based on adherently growing HIV-susceptible cells, with a stable fluorescent reporter gene activated by HIV Tat and Rev. A fluorescence-based assay was designed that measures HIV infection by two parameters relating to the early and the late phases of HIV replication, respectively. Validation of the assay with a panel of nine reference inhibitors yielded effective inhibitory concentrations consistent with published data and allowed discrimination between inhibitors of early and late phases of HIV replication. Finer resolution of the effects of reference drugs on different steps of HIV replication was achieved in secondary time-of-addition assays. The EASY-HIT assay yielded high Z' scores (>0.9) and signal stabilities, confirming its robustness. Screening of the LOPAC(1280) library identified 10 compounds (0.8%), of which eight were known to inhibit HIV, validating the suitability of this assay for screening applications. Studies evaluating anti-HIV activities of natural products with the EASY-HIT technology led to the identification of three novel inhibitory compounds that apparently act at different steps of HIV-1 replication. Furthermore, we demonstrate successful evaluation of plant extracts for HIV-inhibitory activities, suggesting application of this technology for the surveillance of biological extracts with anti-HIV activities. We conclude that the EASY-HIT technology is a versatile tool for the discovery and characterization of HIV inhibitors.

Production of Monoclonal Antibody Against Excretory-Secretory Antigen of Fasciola hepatica and Evaluation of Its Efficacy in the Diagnosis of Fascioliasis.

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Abdolahi Khabisi, Samaneh; Sarkari, Bahador; Moshfe, Abdolali; Jalali, Sedigheh

2017-02-01

Parasitological methods are not helpful for the diagnosis of fascioliasis in acute and invasive periods of the disease. Detection of coproantigens seems to be a suitable alternative approach in the diagnosis of fascioliasis. The present study aimed to develop a reliable antigen detection system, using monoclonal antibodies raised against excretory-secretory (ES) antigen of Fasciola hepatica, for the diagnosis of fascioliasis. Fasciola adult worms were collected from the bile ducts of infected animals. Species of the fluke was determined by polymerase chain reaction-restriction fragment length polymorphism (RFLP-PCR). ES antigen of F. hepatica was prepared. For production of monoclonal antibodies, mice were immunized with ES antigens of F. hepatica. Spleen cells from the immunized mice were fused with NS-1 myeloma cells, using polyethylene glycol. Hybridoma cells secreting specific antibody were expanded and cloned by limiting dilution. Moreover, polyclonal antibody was produced against F. hepatica ES antigen in rabbits. A capture enzyme-linked immunosorbent assay (ELISA) system, using produced monoclonal antibody, was designed and stool samples of infected animals along with control samples were tested by the system. The capture ELISA detected the coproantigen in 27 of 30 (90%) parasitologically confirmed fascioliasis cases, while 4 of 39 (10.25%) samples infected with other parasitic infections showed a positive reaction in this system. No positive reactivity was found with healthy control samples. Accordingly, sensitivity of 90% and specificity of 94.2% were obtained for the capture ELISA system. The results were compared with those obtained with commercial BIO-X ELISA, and a very good (kappa = 0.9) agreement was found between the commercial kit and the developed capture ELISA. Findings of this study showed that the produced monoclonal antibody has appropriate performance for the detection of Fasciola coproantigen in stool samples and can be appropriately

Immunogenicity and safety of high-dose trivalent inactivated influenza vaccine compared to standard-dose vaccine in children and young adults with cancer or HIV infection.

Science.gov (United States)

Hakim, Hana; Allison, Kim J; Van de Velde, Lee-Ann; Tang, Li; Sun, Yilun; Flynn, Patricia M; McCullers, Jonathan A

2016-06-08

Approaches to improve the immune response of immunocompromised patients to influenza vaccination are needed. Children and young adults (3-21 years) with cancer or HIV infection were randomized to receive 2 doses of high-dose (HD) trivalent influenza vaccine (TIV) or of standard-dose (SD) TIV. Hemagglutination inhibition (HAI) antibody titers were measured against H1, H3, and B antigens after each dose and 9 months later. Seroconversion was defined as ≥4-fold rise in HAI titer comparing pre- and post-vaccine sera. Seroprotection was defined as a post-vaccine HAI titer ≥1:40. Reactogenicity events (RE) were solicited using a structured questionnaire 7 and 14 days after each dose of vaccine, and adverse events by medical record review for 21 days after each dose of vaccine. Eighty-five participants were enrolled in the study; 27 with leukemia, 17 with solid tumor (ST), and 41 with HIV. Recipients of HD TIV had significantly greater fold increase in HAI titers to B antigen in leukemia group and to H1 antigen in ST group compared to SD TIV recipients. This increase was not documented in HIV group. There were no differences in seroconversion or seroprotection between HD TIV and SD TIV in all groups. There was no difference in the percentage of solicited RE in recipients of HD TIV (54% after dose 1 and 38% after dose 2) compared to SD TIV (40% after dose 1 and 20% after dose 2, p=0.27 and 0.09 after dose 1 and 2, respectively). HD TIV was more immunogenic than SD TIV in children and young adults with leukemia or ST, but not with HIV. HD TIV was safe and well-tolerated in children and young adults with leukemia, ST, or HIV. Copyright © 2016 Elsevier Ltd. All rights reserved.

Antibody-dependent enhancement of HIV-1 infection in human term syncytiotrophoblast cells cultured in vitro.

Science.gov (United States)

Tóth, F D; Mosborg-Petersen, P; Kiss, J; Aboagye-Mathiesen, G; Zdravkovic, M; Hager, H; Aranyosi, J; Lampé, L; Ebbesen, P

1994-06-01

We examined if Fc receptor-mediated antibody-dependent enhancement (FcR-ADE) or complement-mediated antibody-dependent enhancement (C'-ADE) of virus infection can contribute to increasing replication of HIV-1 in human syncytiotrophoblast (ST) cells. Here we report that both FcR-ADE and C'-ADE may result in enhanced virus release from HIV-1-infected ST cells. We show that FcR-ADE of HIV-1 infection in ST cells is mediated by FcRIII and other FcR(s) belonging to undetermined Fc classes and does not require CD4 receptors, whereas C'-ADE uses both CD4 and CR2-like receptors. FcR-ADE seems to be more efficient in enhancing HIV-1 replication than C'-ADE. While FcR-ADE leads to increased internalization of HIV-1, C'-ADE does not result in enhanced endocytosis of the virus. In addition, antibodies mediating FcR-ADE are reactive with the gp120 viral envelope antigen, whereas antibodies involved in C'-ADE react with the viral transmembrane glycoprotein gp41. Data suggest that both FcR-ADE and C'-ADE may contribute to the spread of HIV-1 from mother to the fetus.

A Sandwich HIV p24 Amperometric Immunosensor Based on a Direct Gold Electroplating-Modified Electrode

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Ning Gan

2012-05-01

Full Text Available Acquired immune deficiency syndrome (AIDS is a severe communicable immune deficiency disease caused by the human immune deficiency virus (HIV. The analysis laboratory diagnosis of HIV infection is a crucial aspect of controlling AIDS. The p24 antigen, the HIV-1 capsid protein, is of considerable diagnostic interest because it is detectable several days earlier than host-generated HIV antibodies following HIV exposure. We present herein a new sandwich HIV p24 immunosensor based on directly electroplating an electrode surface with gold nanoparticles using chronoamperometry, which greatly increased the conductivity and reversibility of the electrode. Under optimum conditions, the electrochemical signal showed a linear relationship with the concentration of p24, ranging from 0.01 ng/mL to 100 ng/mL (R > 0.99, and the detection limit was 0.008 ng/mL. Compared with ELISA, this method increased the sensitivity by more than two orders of magnitude (the sensitivity of ELISA for p24 is about 1 ng/mL. This immunosensor may be broadly applied to clinical samples, being distinguished by its ease of use, mild reaction conditions, guaranteed reproducibility, and good anti-interference ability.

A sandwich HIV p24 amperometric immunosensor based on a direct gold electroplating-modified electrode.

Science.gov (United States)

Zheng, Lei; Jia, Liyong; Li, Bo; Situ, Bo; Liu, Qinlan; Wang, Qian; Gan, Ning

2012-05-18

Acquired immune deficiency syndrome (AIDS) is a severe communicable immune deficiency disease caused by the human immune deficiency virus (HIV). The analysis laboratory diagnosis of HIV infection is a crucial aspect of controlling AIDS. The p24 antigen, the HIV-1 capsid protein, is of considerable diagnostic interest because it is detectable several days earlier than host-generated HIV antibodies following HIV exposure. We present herein a new sandwich HIV p24 immunosensor based on directly electroplating an electrode surface with gold nanoparticles using chronoamperometry, which greatly increased the conductivity and reversibility of the electrode. Under optimum conditions, the electrochemical signal showed a linear relationship with the concentration of p24, ranging from 0.01 ng/mL to 100 ng/mL (R > 0.99), and the detection limit was 0.008 ng/mL. Compared with ELISA, this method increased the sensitivity by more than two orders of magnitude (the sensitivity of ELISA for p24 is about 1 ng/mL). This immunosensor may be broadly applied to clinical samples, being distinguished by its ease of use, mild reaction conditions, guaranteed reproducibility, and good anti-interference ability.

Presenting Influenza A M2e Antigen on Recombinant Spores of Bacillus subtilis.

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Tomasz Łęga

Full Text Available Effective vaccination against influenza virus infection is a serious problem mainly due to antigenic variability of the virus. Among many of investigated antigens, the extracellular domain of the M2 protein (M2e features high homology in all strains of influenza A viruses and antibodies against M2e and is protective in animal models; this makes it a potential candidate for generation of a universal influenza vaccine. However, due to the low immunogenicity of the M2e, formulation of a vaccine based on this antigen requires some modification to induce effective immune responses. In this work we evaluated the possible use of Bacillus subtilis spores as a carrier of the Influenza A M2e antigen in mucosal vaccination. A tandem repeat of 4 consensus sequences coding for human-avian-swine-human M2e (M2eH-A-S-H peptide was fused to spore coat proteins and stably exposed on the spore surface, as demonstrated by the immunostaining of intact, recombinant spores. Oral immunization of mice with recombinant endospores carrying M2eH-A-S-H elicited specific antibody production without the addition of adjuvants. Bacillus subtilis endospores can serve as influenza antigen carriers. Recombinant spores constructed in this work showed low immunogenicity although were able to induce antibody production. The System of influenza antigen administration presented in this work is attractive mainly due to the omitting time-consuming and cost-intensive immunogen production and purification. Therefore modification should be made to increase the immunogenicity of the presented system.

The Laboratory Diagnosis of HIV Infections

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Margaret Fearon

2005-01-01

Full Text Available HIV diagnostic testing has come a long way since its inception in the early 1980s. Current enzyme immunoassays are sensitive enough to detect antibody as early as one to two weeks after infection. A variety of other assays are essential to confirm positive antibody screens (Western blot, polymerase chain reaction [PCR], provide an adjunct to antibody testing (p24 antigen, PCR, or provide additional information for the clinician treating HIV-positive patients (qualitative and quantitative PCR, and genotyping. Most diagnostic laboratories have complex testing algorithms to ensure accuracy of results and optimal use of laboratory resources. The choice of assays is guided by the initial screening results and the clinical information provided by the physician; both are integral to the laboratory's ability to provide an accurate laboratory diagnosis. Laboratories should also provide specific information on specimen collection, storage and transport so that specimen integrity is not compromised, thereby preserving the accuracy of laboratory results. Point of Care tests have become increasingly popular in the United States and some places in Canada over the past several years. These tests provide rapid, on-site HIV results in a format that is relatively easy for clinic staff to perform. However, the performance of these tests requires adherence to good laboratory quality control practices, as well as the backup of a licensed diagnostic laboratory to provide confirmation and resolution of positive or indeterminate results. Laboratory quality assurance programs and the participation in HIV proficiency testing programs are essential to ensure that diagnostic laboratories provide accurate, timely and clinically relevant laboratory results.

Chimeric antigen receptor (CAR)-modified natural killer cell-based immunotherapy and immunological synapse formation in cancer and HIV.

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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.

Safety and anti-HIV assessments of natural vaginal cleansing products in an established topical microbicides in vitro testing algorithm

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Jones Maureen

2010-07-01

Full Text Available Abstract Background At present, there is no effective vaccine or other approved product for the prevention of sexually transmitted human immunodeficiency virus type 1 (HIV-1 infection. It has been reported that women in resource-poor communities use vaginally applied citrus juices as topical microbicides. These easily accessible food products have historically been applied to prevent pregnancy and sexually transmitted diseases. The aim of this study was to evaluate the efficacy and cytotoxicity of these substances using an established topical microbicide testing algorithm. Freshly squeezed lemon and lime juice and household vinegar were tested in their original state or in pH neutralized form for efficacy and cytotoxicity in the CCR5-tropic cell-free entry and cell-associated transmission assays, CXCR4-tropic entry and fusion assays, and in a human PBMC-based anti-HIV-1 assay. These products were also tested for their effect on viability of cervico-vaginal cell lines, human cervical explant tissues, and beneficial Lactobacillus species. Results Natural lime and lemon juice and household vinegar demonstrated anti-HIV-1 activity and cytotoxicity in transformed cell lines. Neutralization of the products reduced both anti-HIV-1 activity and cytotoxicity, resulting in a low therapeutic window for both acidic and neutralized formulations. For the natural juices and vinegar, the IC50 was ≤ 3.5 (0.8-3.5% and the TC50 ≤ 6.3 (1.0-6.3%. All three liquid products inhibited viability of beneficial Lactobacillus species associated with vaginal health. Comparison of three different toxicity endpoints in the cervical HeLa cell line revealed that all three products affected membrane integrity, cytosolic enzyme release, and dehydrogenase enzyme activity in living cells. The juices and vinegar also exerted strong cytotoxicity in cervico-vaginal cell lines, mainly due to their acidic pH. In human cervical explant tissues, treatment with 5% lemon or lime juice

Live attenuated measles vaccine expressing HIV-1 Gag virus like particles covered with gp160ΔV1V2 is strongly immunogenic

International Nuclear Information System (INIS)

Guerbois, Mathilde; Moris, Arnaud; Combredet, Chantal; Najburg, Valerie; Ruffie, Claude; Fevrier, Michele; Cayet, Nadege; Brandler, Samantha; Schwartz, Olivier; Tangy, Frederic

2009-01-01

Although a live attenuated HIV vaccine is not currently considered for safety reasons, a strategy inducing both T cells and neutralizing antibodies to native assembled HIV-1 particles expressed by a replicating virus might mimic the advantageous characteristics of live attenuated vaccine. To this aim, we generated a live attenuated recombinant measles vaccine expressing HIV-1 Gag virus-like particles (VLPs) covered with gp160ΔV1V2 Env protein. The measles-HIV virus replicated efficiently in cell culture and induced the intense budding of HIV particles covered with Env. In mice sensitive to MV infection, this recombinant vaccine stimulated high levels of cellular and humoral immunity to both MV and HIV with neutralizing activity. The measles-HIV virus infected human professional antigen-presenting cells, such as dendritic cells and B cells, and induced efficient presentation of HIV-1 epitopes and subsequent activation of human HIV-1 Gag-specific T cell clones. This candidate vaccine will be next tested in non-human primates. As a pediatric vaccine, it might protect children and adolescents simultaneously from measles and HIV.