anti-HIV Ab Research Articles

Multiscale affinity maturation simulations to elicit broadly neutralizing antibodies against HIV.

The design of vaccines against highly mutable pathogens, such as HIV and influenza, requires a detailed understanding of how the adaptive immune system responds to encountering multiple variant antigens (Ags). Here, we describe a multiscale model of B cell receptor (BCR) affinity maturation that employs actual BCR nucleotide sequences and treats BCR/Ag interactions in atomistic detail. We apply the model to simulate the maturation of a broadly neutralizing Ab (bnAb) against HIV. Starting from a germline precursor sequence of the VRC01 anti-HIV Ab, we simulate BCR evolution in response to different vaccination protocols and different Ags, which were previously designed by us. The simulation results provide qualitative guidelines for future vaccine design and reveal unique insights into bnAb evolution against the CD4 binding site of HIV. Our model makes possible direct comparisons of simulated BCR populations with results of deep sequencing data, which will be explored in future applications.

Seroprevalence of HBsAg, Anti-HBs, Anti-HCV and Anti-HIV in Behçet’s Disease

Introduction: Behçet's disease defined by Turkish dermatologist Hulusi Behçet is an inflammatory disease of unknown etiology and characterized by recurrent oral aphthous ulcers, genital ulcers, uveitis and skin lesions. We aimed to evaluate hepatitis B virus, hepatitis C virus and human immunodeficiency virus seroprevalence in Behçet's Disease.
 Material and Method: Patients diagnosed with Behçet’s diseaseand followed up by the dermatology outpatient clinic during 12-years period between July 2008 and July 2020 were retrospectively analyzed. Demographic datas and HBsAg, anti-HBs, anti-HCV, Anti-HIV results of the patients were recorded.
 Results: 359 patients with Behçet’s disease were been evaluated in this study. Of these patients, 189 (52.6%) were female, 170 (47.4%) were male and the mean age was 37.7±12.3 years. HBsAg was positive in 6 (1.6%) patients and Anti-Hbs ab in 82 (7.7%) patients. Anti HIV ab was negative in all patients. Anti-HCV antibodies were found positive in only one case (0.2%), and this was confirmed by testing for hepatitis C virus-ribonucleic acid (HCV RNA). HCV RNA was negative in this patient. 
 Conclusion: When compared with the general population, seropositivity rates were not detected to be high in Behçet's patients. In fact, the immunity rates were found very low. Based on such a finding, it was concluded that screening is required due to increasing immunosupressive treatments today, and individuals should be vaccinated in cases where HBV indicators are negative.In the other studies, investigating the entity, seropositivity rates have been found similar to those in the population. Considering that serological data show regional differences, we thought that, our study will contribute to the literature both national and international grades due to large patient population in our region.

2516. Persistence of Anti-HIV Antibodies in HIV-1-infected Patients on Combination Antiretroviral Therapy (cART) with Prolonged Viral Suppression

BackgroundDespite years of cART with sustained HIV-RNA plasma viral load (pVL) < 50 copies/mL, antibodies (Abs) to HIV-1 proteins persist. The reasons for this are unknown but may reflect long-lived B cell responses and/or persistence of antigen. To address which of these may be the case, we compared decay rates of anti-HIV Abs to those of anti-Measles Abs.MethodsA cohort of 10 HIV-infected patients on cART with pVL < 50 (average 3 years, range 0–7.1 years) were studied. Baseline and 5-year follow-up serum were collected and assessed for anti-HIV-1 Abs via western blot (Cambridge Biotech WB kit), with additional densiometric analysis used for quantitative calculation of a western blot “score” that was normalized to control specimens. The kinetics of measles Abs titers over the same 5-year period were also analyzed by the quantitative Serion Measles IgG ELISA kit, given a history of prior vaccination in these participants. McNemar’s and paired t-tests were used for analysis.ResultsAll 10 patients exhibited persistence of anti-HIV-1 Abs at ≥ 5 year follow-up as determined by persistence of ≥ 2 diagnostic bands on WB (P = 0.003). The patterns for all 10 participants varied individually by patient with each exhibiting a unique profile (representative figure); 7/10 patients had WBs that could be analyzed quantitatively and showed no significant change over the study period (average baseline score 5.9 vs 5.3 at follow-up, P = 0.26). 7/9 patients had valid measles IgG measurements showing a consistent but nonsignificant decline over the same 5-year study period (measles titer 55–2800 mIU/mL at baseline vs 50–1300 mIU/mL at follow-up, n = 9, P = 0.18).ConclusionThe mechanism leading to the persistence of anti-HIV-1 Abs in HIV-infected individuals with prolonged viral suppression has been unclear. The general decline in anti-Measles IgG titer over the 5-year observational period in 7/9 patients is likely to be explained by waning B cell-mediated humoral immunity in these vaccinated individuals and consistent with their lack of ongoing exposure to this pathogen. The persistence of anti-HIV-1 Abs over the same 5-year period, on the other hand, may indicate persistent HIV-1 viral protein production either from active reservoirs or by transcription of “defective” HIV-1 proviruses as recently reported. Disclosures All authors: No reported disclosures.

Boosting of Markers of Fcγ Receptor Function in Anti-HIV Antibodies During Structured Treatment Interruption.

Anti-HIV envelope (Env) antibodies elicit important Fc receptor functions, including FcγRIIIa-mediated natural killer cell killing of opsonized infected targets. How these antibodies evolve during HIV infection and treatment remains poorly understood. We describe changes in anti-HIV Env IgG using longitudinal samples from seroconverter subjects treated soon after infection and later during periods of structured treatment interruption (STI). Our well-validated dimeric rsFcγR binding assays combine effects of opsonizing antibody subclasses, epitopes, and geometries to provide a measure of FcγR (Fcγ receptor)-mediated functionality. IgG1 anti-Env titers diminished rapidly during antiretroviral therapy (ART; t1/2 3.0 ± 0.8 months), while the dimeric rsFcγRIIIa activity persisted longer (t1/2 33 ± 11 months), suggesting that there is maintenance of functional antibody specificities within the diminished pool of anti-HIV Env Abs. The initial antibody response to infection in two subjects was characterized by approximately fivefold higher FcγRIIIa compared with FcγRIIa binding activity. Uncoupling of FcγRIIa and FcγRIIIa activities may be a distinct feature of the early antibody response that preferentially engages FcγRIIIa-mediated effector functions. Two to three STI cycles, even with low viremia, were sufficient to boost dimeric FcγR activity in these seroconverter subjects. We hypothesize that increased humoral immunity induced by STI is a desirable functional outcome potentially achievable by therapeutic immunization during ART. We conclude that controlled viral antigen exposure under the protection of suppressive ART may be effective in eliciting FcγR-dependent function in support of viral reactivation and kill strategies.

Human Anti-HIV-1 gp120 Monoclonal Antibodies with Neutralizing Activity Cloned from Humanized Mice Infected with HIV-1.

Broadly neutralizing, anti-HIV-1 gp120 mAbs have been isolated from infected individuals, and there is considerable interest in developing these reagents for Ab-based immunoprophylaxis and treatment. As a means to identify potentially new anti-HIV Abs, we exploited humanized NOD-scid IL2rγnull mice systemically infected with HIV-1 to generate a wide variety of Ag-specific human mAbs. The Abs were encoded by a diverse range of variable gene families and Ig classes, including IgA, and several showed significant levels of somatic mutation. Moreover, the isolated Abs not only bound target Ags with similar affinity as broadly neutralizing Abs, they also demonstrated neutralizing ability against multiple HIV-1 clades. The use of humanized mice will allow us to use our knowledge of HIV-1 gp120 structure and function, and the immune response targeting this protein, to generate native human prophylactic Abs to reduce the infection and spread of HIV-1.

Seroprevalence occurrence of viral hepatitis and HIV among hemodialysis patients

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

Patients with chronic renal failure (CRF) were on maintenance invasive haemodialysis (HD) procedure. This procedure by itself affects immunity of the patients and they become more susceptible to viral infections. We investigate the occurrence of HBV HCV and HIV infections in patients with hemodialysis. A retrospective study of 430 endstage renal failure patients referred to hemodialysis department at AlKindy Teaching Hospital Baghdad, Iraq from January 2015 to January 2017 was conducted. Patients were investigated for HBsAg using enzymelabeled antigen test (ForesightEIAUSA) HCV Abs (IgG) specific immunoglobulin using a HCV enzymelabeled antigen test (ForesightEIAUSA) and anti HIV Abs (IgG) using enzymelabeled antigen test (ForesightEIAUSA). The frequency of HBV infection in the first year was not significant between males (111%) and females (000%)(P = 0295). About HCV also there are no significant differences between males (1263%) and females (931%)(P = 0347). After one year of follow up the frequencies of HBV and HCV were not significant between two sexes. Additionally none of the patients had an HIV infection. This study brings to light that HBV and HCV have the same frequencies in both genders and lower occurrence with time. Furthermore HIV was not detected in those patients.

Increasing the Clinical Potential and Applications of Anti-HIV Antibodies.

Preclinical and early human clinical studies of broadly neutralizing antibodies (bNAbs) to prevent and treat HIV infection support the clinical utility and potential of bNAbs for prevention, postexposure prophylaxis, and treatment of acute and chronic infection. Observed and potential limitations of bNAbs from these recent studies include the selection of resistant viral populations, immunogenicity resulting in the development of antidrug (Ab) responses, and the potentially toxic elimination of reservoir cells in regeneration-limited tissues. Here, we review opportunities to improve the clinical utility of HIV Abs to address these challenges and further accomplish functional targets for anti-HIV Ab therapy at various stages of exposure/infection. Before exposure, bNAbs’ ability to serve as prophylaxis by neutralization may be improved by increasing serum half-life to necessitate less frequent administration, delivering genes for durable in vivo expression, and targeting bNAbs to sites of exposure. After exposure and/or in the setting of acute infection, bNAb use to prevent/reduce viral reservoir establishment and spread may be enhanced by increasing the potency with which autologous adaptive immune responses are stimulated, clearing acutely infected cells, and preventing cell–cell transmission of virus. In the setting of chronic infection, bNAbs may better mediate viral remission or “cure” in combination with antiretroviral therapy and/or latency reversing agents, by targeting additional markers of tissue reservoirs or infected cell types, or by serving as targeting moieties in engineered cell therapy. While the clinical use of HIV Abs has never been closer, remaining studies to precisely define, model, and understand the complex roles and dynamics of HIV Abs and viral evolution in the context of the human immune system and anatomical compartmentalization will be critical to both optimize their clinical use in combination with existing agents and define further strategies with which to enhance their clinical safety and efficacy.

Non-Neutralizing Antibodies Directed against HIV and Their Functions.

B cells produce a plethora of anti-HIV antibodies (Abs) but only few of them exhibit neutralizing activity. This was long considered a profound limitation for the enforcement of humoral immune responses against HIV-1 infection, especially since these neutralizing Abs (nAbs) are extremely difficult to induce. However, increasing evidence shows that additional non-neutralizing Abs play a significant role in decreasing the viral load, leading to partial and sometimes even total protection. Mechanisms suspected to participate in protection are numerous. They involve the Fc domain of Abs as well as their Fab part, and consequently the induced Ab isotype will be determinant for their functions, as well as the quantity and quality of the Fc-receptors (FcRs) expressed on immune cells. Fc-mediated inhibitory functions, such as Ab-dependent cellular cytotoxicity, antibody-dependent cellular phagocytosis, aggregation, and even immune activation have been proposed. However, as for nAbs, the non-neutralizing activities are limited to a subset of anti-HIV Abs. An improved in-depth characterization of the Abs displaying these functional responses is required for the development of new vaccination strategies, which aim to selectively trigger the B cells able to induce the right functional Ab combinations both at the right place and at the right time. This review summarizes our current knowledge on non-neutralizing functional inhibitory Abs and discusses the potential benefit of inducing them via vaccination. We also provide new insight into the roles of the FcγR-mediated Ab therapeutics in clinical trials for HIV diseases.

Diversity of Antiviral IgG Effector Activities Observed in HIV-Infected and Vaccinated Subjects.

Diverse Ab effector functions mediated by the Fc domain have been commonly associated with reduced risk of infection in a growing number of nonhuman primate and human clinical studies. This study evaluated the anti-HIV Ab effector activities in polyclonal serum samples from HIV-infected donors, VAX004 vaccine recipients, and healthy HIV-negative subjects using a variety of primary and cell line-based assays, including Ab-dependent cellular cytotoxicity (ADCC), Ab-dependent cell-mediated viral inhibition, and Ab-dependent cellular phagocytosis. Additional assay characterization was performed with a panel of Fc-engineered variants of mAb b12. The goal of this study was to characterize different effector functions in the study samples and identify assays that might most comprehensively and dependably capture Fc-mediated Ab functions mediated by different effector cell types and against different viral targets. Deployment of such assays may facilitate assessment of functionally unique humoral responses and contribute to identification of correlates of protection with potential mechanistic significance in future HIV vaccine studies. Multivariate and correlative comparisons identified a set of Ab-dependent cell-mediated viral inhibition and phagocytosis assays that captured different Ab activities and were distinct from a group of ADCC assays that showed a more similar response profile across polyclonal serum samples. The activities of a panel of b12 monoclonal Fc variants further identified distinctions among the ADCC assays. These results reveal the natural diversity of Fc-mediated Ab effector responses among vaccine recipients in the VAX004 trial and in HIV-infected subjects, and they point to the potential importance of polyfunctional Ab responses.

Enhancing Virion Tethering by BST2 Sensitizes Productively and Latently HIV-infected T cells to ADCC Mediated by Broadly Neutralizing Antibodies.

Binding of anti-HIV antibodies (Abs) to envelope (Env) glycoproteins on infected cells can mark them for elimination via antibody-dependent cell-mediated cytotoxicity (ADCC). BST2, a type I interferon (IFN)-stimulated restriction factor that anchors nascent Env-containing virions at the surface of infected cells has been shown to enhance ADCC functions. In a comprehensive analysis of ADCC potency by neutralizing anti-HIV Abs (NAbs), we show in this study that NAbs are capable of mediating ADCC against HIV-infected T cells with 3BNC117, PGT126 and PG9 being most efficient. We demonstrate that HIV-induced BST2 antagonism effectively attenuates Ab binding and ADCC responses mediated by all classes of NAbs that were tested. Interestingly, IFNα treatment can reverse this effect in a BST2-dependent manner. Importantly, while reactivated latent T cell lines display some susceptibility to ADCC mediated by broadly NAbs, inactivating BST2 viral countermeasures and/or exogenous IFNα augment their elimination. Overall, our findings support the notion that NAbs can induce ADCC. They highlight that while BST2 antagonism by HIV promotes ADCC evasion, strategies aimed at restoring BST2 restriction could improve anti-HIV responses and potentially provide a means to eliminate reactivated cells in latent reservoirs.

Anti-HIV Antibody–Dependent Activation of NK Cells Impairs NKp46 Expression

There is much interest in the potential of Ab-dependent cellular cytotoxicity (ADCC) to slow disease progression following HIV infection. Despite several studies demonstrating a positive association between ADCC and slower disease progression, it is possible that continued stimulation of NK cells by ADCC during chronic HIV infection could render these cells dysfunctional. Indeed, activation of NK cells by ADCC results in matrix metalloproteinase-induced reductions in CD16 expression and activation refractory periods. In addition, ex vivo analyses of NK cells from HIV-infected individuals revealed other alterations in phenotype, such as decreased expression of the activating NKp46 receptor that is essential for NK-mediated antitumor responses and immunity from infection. Because NKp46 shares a signaling pathway with CD16, we hypothesized that activation-induced downregulation of both receptors could be controlled by a common mechanism. We found that activation of NK cells by anti-HIV or anti-CD16 Abs resulted in NKp46 downregulation. The addition of a matrix metalloproteinase inhibitor attenuated NKp46 downregulation following NK cell activation by anti-HIV Abs. Consequently, these results suggest that continued stimulation through CD16 has the potential to impair natural cytotoxicity via attenuation of NKp46-dependent signals.

Protective effect of vaginal application of neutralizing and nonneutralizing inhibitory antibodies against vaginal SHIV challenge in macaques.

Definition of antibody (Ab) functions capable of preventing mucosal HIV transmission may be critical to both effective vaccine development and the prophylactic use of monoclonal Abs. Although direct antibody-mediated neutralization is highly effective against cell-free virus, increasing evidence suggests an important role for immunoglobulin G (IgG) Fcγ receptor (FcγR)-mediated inhibition of HIV replication. Thus, a panel of well-known neutralizing (NAbs) and nonneutralizing Abs (NoNAbs) were screened for their ability to block HIV acquisition and replication in vitro in either an independent or FcγR-dependent manner. Abs displaying the highest Fc-mediated inhibitory activity in various in vitro assays were selected, formulated for topical vaginal application in a microbicide gel, and tested for their antiviral activity against SHIVSF162P3 vaginal challenge in non-human primates (NHPs). A combination of three NAbs, 2G12, 2F5, and 4E10, fully prevented simian/human immunodeficiency virus (SHIV) vaginal transmission in 10 out of 15 treated NHPs, whereas a combination of two NoNAbs, 246-D and 4B3, although having no impact on SHIV acquisition, reduced plasma viral load. These results indicate that anti-HIV Abs with distinct neutralization and inhibitory functions differentially affect in vivo HIV acquisition and replication, by interfering with early viral replication and dissemination. Therefore, combining diverse Ab properties may potentiate the protective effects of anti-HIV-Ab-based strategies.

Comparison of Antibody Repertoires Produced by HIV-1 Infection, Other Chronic and Acute Infections, and Systemic Autoimmune Disease

BackgroundAntibodies (Abs) produced during HIV-1 infection rarely neutralize a broad range of viral isolates; only eight broadly-neutralizing (bNt) monoclonal (M)Abs have been isolated. Yet, to be effective, an HIV-1 vaccine may have to elicit the essential features of these MAbs. The V genes of all of these bNt MAbs are highly somatically mutated, and the VH genes of five of them encode a long (≥20 aa) third complementarity-determining region (CDR-H3). This led us to question whether long CDR-H3s and high levels of somatic mutation (SM) are a preferred feature of anti-HIV bNt MAbs, or if other adaptive immune responses elicit them in general.Methodology and Principal FindingsWe assembled a VH-gene sequence database from over 700 human MAbs of known antigen specificity isolated from chronic (viral) infections (ChI), acute (bacterial and viral) infections (AcI), and systemic autoimmune diseases (SAD), and compared their CDR-H3 length, number of SMs and germline VH-gene usage. We found that anti-HIV Abs, regardless of their neutralization breadth, tended to have long CDR-H3s and high numbers of SMs. However, these features were also common among Abs associated with other chronic viral infections. In contrast, Abs from acute viral infections (but not bacterial infections) tended to have relatively short CDR-H3s and a low number of SMs, whereas SAD Abs were generally intermediate in CDR-H3 length and number of SMs. Analysis of VH gene usage showed that ChI Abs also tended to favor distal germline VH-genes (particularly VH1-69), especially in Abs bearing long CDR-H3s.Conclusions and SignificanceThe striking difference between the Abs produced during chronic vs. acute viral infection suggests that Abs bearing long CDR-H3s, high levels of SM and VH1-69 gene usage may be preferentially selected during persistent infection.

Seroprevalence of Hepatitis B surface antigen, antibodies to the Hepatitis C virus, and human immunodeficiency virus in a hospital-based population in Jaipur, Rajasthan

Background:Hepatitis B, hepatitis C, and HIV infections are a serious global and public health problem. To assess the magnitude and dynamics of disease transmission and for its prevention and control, the study of its seroprevalence is important. A private hospital catering to the needs of a large population represents an important center for serological surveys. Available data, at Rajasthan state level, on the seroprevalence of these bloodborne pathogens is also very limited.Objective:A study was undertaken to estimate the seroprevalence of hepatitis B surface antigen (HBsAg) and antibodies to hepatitis C (anti-HCV Ab) and human immunodeficiency virus (anti-HIV Ab) in both the sexes and different age groups in a hospital-based population in Jaipur, Rajasthan.Materials and Methods:Serum samples collected over a period of 14 months from patients attending OPDs and admitted to various IPDs of Fortis Escorts Hospital, Jaipur, were subjected within the hospital-based lab for the detection of HBsAg and anti-HCV Ab and anti-HIV Ab using rapid card tests. This was followed by further confirmation of all reactive samples by a microparticle enzyme immunoassay (Abbott AxSYM) at Super Religare Laboratories (formerly SRL Ranbaxy) Reference Lab, Mumbai.Results:The seroprevalence of HBsAg was found to be 0.87%, of anti-HCV Ab as 0.28%, and of anti-HIV Ab as 0.35%.Conclusion:The study throws light on the magnitude of viral transmission in the community in the state of Rajasthan and provides a reference for future studies.

Kaposi Sarcoma with Visceral Involvement in a HIV- Neg Female Patient

Background: Kaposi sarcoma is a rare multifocal malignancy of hemo-lymphatic tissue that ,its precise etiology is unknown .There are reports showing the role for an infective viral agent. In HIV disease ,its prevalence is far more common as well in immune- suppressed patients it is more prevalent. Report of the case: We presented a 78 year- old woman with multiple tender purplish plaques on her extremities for a month. In her past history she was healthy until 2 years ago when she noted two plaques on her left foot and a similar one on her right hand. In skin biopsies, there were spindle shaped cells presented with hypervascularity consistent with Kaposi's sarcoma.She had refused any kind of treatment . No positive signs were found in physical examination. Routine laboratory data was normal. Anti-HIV ab test was negative although she showed significantly lower levels of CD4+ T- lymphocytes in her blood profile. Thoraco-abdominal CT demonstrated lesions highly suggestive of hepato- splenic involvement as multiple hypodense nodules. Because of patient's disagreement and the reluctance of GI surgeons to remove the masse, we refused to refer her for invasive procedures .

The HIV-Neutralizing Monoclonal Antibody 4E10 Recognizes N-Terminal Sequences on the Native Antigen

Characterization of the epitope recognized by the broadly neutralizing anti-HIV Ab 4E10 has, heretofore, focused on a linear sequence from the gp41 pretransmembrane region (PTMR). Attempts to generate neutralizing Abs based on this linear epitope sequence have been unsuccessful. We have characterized the antigenic determinants on recombinant glycosylated full-length Ags, and nonglycosylated and truncated Ags recognized by 4E10 using epitope extraction and excision assays in conjunction with MALDI mass spectrometry. The mAb recognized the peptides (34)LWVTVYYGVPVWK(46) and (512)AVGIGAVFLGFLGAAGSTMGAASMTLTVQAR(542) located at the N-terminal region of gp120 and gp41, respectively. Immunoassays verified AV(L/M)FLGFLGAA as the gp41 epitope core. Recognition of the peptide from the gp41 PTMR was detected only in constructs in which the N termini of the mature envelope proteins were missing. In this region, the epitope core is located in the sequence (672)WFDITNWLWY(681). We hypothesize that the hydrophobic surface of the paratope functions as a "trap" for the viral sequences, which are responsible for insertion into the host cell membrane. As the N-terminal region of gp120, the fusogenic peptide of gp41, and the PTMR of gp41 show high sequence homology among various HIV strains, this model is consistent with the broadly neutralizing capabilities of 4E10.

Hepatitis B and C among thalassemiac patients in Iran: A multicenter study

BACKGROUND/OBJECTIVES: Regular blood transfusions for patients with thalassemia have improved their overall survival but carry a definite risk of being infected with bloodborne viruses, especially hepatitis B and C. Nowadays, this is a major health concern for these patients. We conducted this multicenter study to provide the epidemiologic data of hepatitis B and C among a large number of thalassemic patients in Iran since there is no sufficient and comprehensive data in this issue from Iran. METHODS: We enrolled 732 patients with thalassemia major or thalassemia intermediate in five provinces of Iran, including Tehran (n=410), Kerman (n=100), Ghazvin (n=95), Semnan (n=81), and Zanjan (n=46). The initial data were recorded and the sera were tested for HBs Ag, anti-HCV Ab, and anti-HIV Ab using ELISA 2nd generation and confirmed by RIBA 2nd generation. Second samples tested to measure hemoglobin and serum ferritin levels. RESULTS: The patient group consisted of 413 males and 319 females with a mean age of 17.9 ± 9.0 years. Of these, 141 patients (19.3%) were anti-HCV Ab positive, 11 patients (1.5%) were HBsAg positive, and there was no anti-HIV positive case. Univariate analysis showed that thalassemia major (p=0.01), older age (p=0.001), longer transfusion duration (0.000), HBsAg seropositivity (p=0.01), and higher serum ferritin level (p=0.002) were significantly associated with higher HCV prevalence. Furthermore, HCV prevalence rate has significantly dropped after applying anti-HCV Ab screening in blood donors (22.8% versus 2.6%, p=0.000). Using multivariate analysis, thalassemia major (p=0.002), age (p=0.000), serum ferritin level (p=0.003), as well as consuming unscreened blood (p=0.005) showed up as the factors independently associated with HCV infection. CONCLUSION: HCV infection prevalence rate is much higher among thalassemics compared to HBV and HIV in Iran. Screening of blood donors seems to be able to decrease prevalence and incidence rate of HCV infection effectively.

Évaluation des performances analytiques des tubes à prélèvement (BD Vacutainer TM SST TM) vis-à-vis de la recherche des Ac anti-VIH, anti-HTLV, anti-VHC, anti-HBc, anti-HBs, anti-CMV, des Ag HBs, P24 VIH, et de l'alanine aminotransférase

The Laboratory of Viral Diseases Immunology (Laboratoire d'Immunologie des Maladies Virales) of the Northern Region Blood Bank (Établissement Français du Sang Nord de France) performs between 180.000 and 200.000 viral blood qualifications per year. The use of a serum gel separator evacuated tube should contribute to improve the quality of the pre-analytical phase. However, it must not impact negatively the analytical performances. We evaluated such tube within our specific environment and with the various reagents used in routine. The open study compared the BD Vacutainer TM plain tube (7 mL, non siliconised) with the BD Vacutainer TM SST TM tube (6 mL siliconised with serum gel separator) against the anti-HIV, anti-HTLV, anti-HCV, anti-HBc, anti-HBs, anti-CMV antibodies, the HBs, HIV P24 antigen and the alanine aminotransferase. The study objectives were to find potential gel interference, to verify the diagnostic sensitivity, reagents specificity, and reproducibility. The results analysis show : equivalent performances with the anti-HIV Ab (Anti HIV 1 2 recombinant - Biotest et Genscreen HIV 1 2 - Sanofi), anti HIV WB Ab (new Lav Blot 1 - Sanofi), anti-HBs Ab (Enzygnost anti-HBs micro - Behring), anti-HBc Ab (HBc Elisa Test System - Ortho), anti-CMV Ab (Enzygnost anti-CMV IgG + M - Behring) kits; lower performances with: The Vironostika HIV Uni Form II plus 0 - Organon kit with a − 3.5 % signal decrease around the ratio R = 2.7 for positive anti-HIV Ab. The Elisa test System 3 Ag HBs - Ortho kit with an increase of the mean ratio of the negative Ag HBs samples; better performances with: the Vironostika HIV 1 Antigen - Organon kit with a + 10 % signal increase around the thresold ratio R = 1 for positive Ag HIV samples. This deserves further study to verify that the specifity is maintained. The HTLV Type 1 et 2 EIA - Ortho kit with + 8 % signal increase around the ratio R = 2 for positive anti-HTLV Ab samples without change of the specificity. The Ortho HCV 3.0 Elisa Test System and HTLV Type 1 et 2 EIA kits with a clear and significant improvement of the reproducibility of the anti-HCV and anti-HTLV Ab screenings. The results of this evaluation, together with the intrinsic BD SST TM tube characteristics, lead to the conclusion that its use would contribute to improve the quality. Because of the specificities of each laboratory, a change of tube type, as with any other material or reagent, request a close monitoring of the first results to confirm the absence of negative effects.

Overexpression of lymphocytic GD3 ganglioside and presence of anti-GD3 antibodies in patients with HIV infection.

This study was undertaken to analyze the role of disialoganglioside GD3 in HIV infection and disease progression. We report here the results obtained by both ex vivo and in vitro experiments on (1) surface and cytoplasmic expression and distribution of GD3 in HIV-infected cells, (2) the presence of anti-GD3 antibodies in sera of patients with HIV infection in various stages of the disease, and (3) the association of GD3 expression with HIV-related apoptotic events. GD3 expression was determined by high-performance thin-layer chromatography (HPTLC) and lipid-bound sialic acid and by static and flow cytometric analyses in peripheral blood lymphocytes from 22 AIDS patients, 20 anti-HIV Ab(+) asymptomatic subjects, and 25 healthy donors. Results obtained clearly indicated a significantly higher expression of plasma membrane GD3 content in lymphocytes from HIV-infected patients with respect to healthy controls. These HIV-induced perturbations of glycosphingolipid metabolism could be detected in all stages of the disease, including asymptomatic individuals. In addition, a significant percentage of patients showing disease progression displayed in serum samples an increased presence of anti-GD3 antibodies. Interestingly, ex vivo studies of lymphocytes from patients with HIV infection also indicated that GD3 expression is strictly associated with annexin V binding, an early marker of apoptosis. Moreover, cytofluorimetric analysis showed that virtually all anti-p24 Ab-positive cells were also immunolabeled with anti-GD3 antibodies. Accordingly, in vitro studies showed a significant redistribution and increase in GD3 expression in cultured U937 cells chronically infected with HIV-1 with respect to uninfected counterparts. In conclusion, our data clearly indicate that a significant increase in GD3 content in HIV-infected lymphocytes can occur and that this GD3 overexpression is paralleled by the presence of anti-GD3 antibodies in the plasma of patients. This is the first demonstration that disialoganglioside GD3, independent of the therapeutic schedule employed, can be considered as one of the early markers of HIV infection and can contribute to the early events leading to T cell depletion by apoptosis.