scholarly journals Antibody response against selected epitopes in the HIV-1 envelope gp41 ectodomain contributes to reduce viral burden in HIV-1 infected patients

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Rute Marcelino ◽  
Filipa Gramacho ◽  
Francisco Martin ◽  
Pedro Brogueira ◽  
Nuno Janeiro ◽  
...  

AbstractThe ectodomain of gp41 is the target of potent binding and neutralizing antibodies (NAbs) and is being explored in new strategies for antibody-based HIV vaccines. Previous studies have suggested that the W164A-3S (3S) and EC26-2A4 (EC26) peptides located in the gp41 ectodomain may be potential HIV vaccine candidates. We assessed 3S- and EC26-specific binding antibody responses and related neutralizing activity in a large panel of chronic HIV-1-infected Portuguese individuals on ART. A similar proportion of participants had antibodies binding to 3S (9.6%) and EC26 (9.9%) peptides but the level of reactivity against 3S was significantly higher compared to EC26, except in the rare patients with double peptide reactivity. The higher antigenicity of 3S was unrelated with disease stage, as assessed by CD4+ T cell counts, but it was directly related with plasma viral load. Most patients that were tested (89.9%, N = 268) showed tier 1 neutralizing activity, the potency being inversely associated with plasma viral load. In the subset of patients that were tested for neutralization of tier 2 isolates, neutralization breadth was inversely correlated with plasma viral load and directly correlated with CD4+ T cell counts. These results are consistent with a role for neutralizing antibodies in controlling viral replication and preventing the decline of CD4+ T lymphocytes. Importantly, in patients with 3S-specific antibodies, neutralizing titers were inversely correlated with viral RNA levels and proviral DNA levels. Moreover, patients with 3S and/or EC26-specific antibodies showed a 1.9-fold higher tier 2 neutralization score than patients without antibodies suggesting that 3S and/or EC26-specific antibodies contribute to neutralization breadth and potency in HIV-1 infected patients. Overall, these results suggest that antibodies targeting the S3 and EC26 epitopes may contribute to reduce viral burden and provide further support for the inclusion of 3S and EC26 epitopes in HIV-1 vaccine candidates.

2016 ◽  
Vol 1 (2) ◽  
pp. 260 ◽  
Author(s):  
Yolanda D. Mahnke ◽  
Kipper Fletez-Brant ◽  
Irini Sereti ◽  
Mario Roederer

Background. Highly active antiretroviral therapy induces clinical benefits to HIV-1 infected individuals, which can be striking in those with progressive disease. Improved survival and decreased incidence of opportunistic infections go hand in hand with a suppression of the plasma viral load, an increase in peripheral CD4+ T-cell counts, as well as a reduction in the activation status of both CD4+ and CD8+ T cells.Methods. We investigated T-cell dynamics during ART by polychromatic flow cytometry in total as well as in HIV-1-specific CD4+ and CD8+ T cells. We also measured gene expression by single cell transcriptomics to assess functional state.Results. The cytokine pattern of HIV-specific CD8+ T cells was not altered after ART, though their magnitude decreased significantly as the plasma viral load was suppressed to undetectable levels. Importantly, while CD4+ T cell numbers increased substantially during the first year, the population did not normalize: the increases were largely due to expansion of mucosal-derived CCR4+ CD4+ TCM; transcriptomic analysis revealed that these are not classical Th2-type cells.Conclusion. The apparent long-term normalization of CD4+ T-cell numbers following ART does not comprise a normal balance of functionally distinct cells, but results in a dramatic Th2 shift of the reconstituting immune system.


AIDS ◽  
2010 ◽  
Vol 24 (2) ◽  
pp. 195-204 ◽  
Author(s):  
Kavidha Reddy ◽  
Cheryl A Winkler ◽  
Lise Werner ◽  
Koleka Mlisana ◽  
Salim S Abdool Karim ◽  
...  

2016 ◽  
Vol 90 (22) ◽  
pp. 10423-10430 ◽  
Author(s):  
Heather A. Prentice ◽  
Hailin Lu ◽  
Matthew A. Price ◽  
Anatoli Kamali ◽  
Etienne Karita ◽  
...  

ABSTRACT In individuals with HIV-1 infection, depletion of CD4 + T cells is often accompanied by a malfunction of CD8 + T cells that are persistently activated and/or exhausted. While the dynamics and correlates of CD4 counts have been well documented, the same does not apply to CD8 counts. Here, we examined the CD8 counts in a cohort of 497 Africans with primary HIV-1 infection evaluated in monthly to quarterly follow-up visits for up to 3 years in the absence of antiretroviral therapy. Statistical models revealed that (i) CD8 counts were relatively steady in the 3- to 36-month period of infection and similar between men and women; (ii) neither geography nor heterogeneity in the HIV-1 set-point viral load could account for the roughly 10-fold range of CD8 counts in the cohort ( P > 0.25 in all tests); and (iii) factors independently associated with relatively high CD8 counts included demographics (age ≤ 40 years, adjusted P = 0.010) and several human leukocyte antigen class I (HLA-I) alleles, including HLA-A*03:01 ( P = 0.013), B*15:10 ( P = 0.007), and B*58:02 ( P < 0.001). Multiple sensitivity analyses provided supporting evidence for these novel relationships. Overall, these findings suggest that factors associated with the CD8 count have little overlap with those previously reported for other HIV-1-related outcome measures, including viral load, CD4 count, and CD4/CD8 ratio. IMPORTANCE Longitudinal data from 497 HIV-1 seroconverters allowed us to systematically evaluate the dynamics and correlates of CD8 + T-cell counts during untreated primary HIV-1 infection in eastern and southern Africans. Our findings suggest that individuals with certain HLA-I alleles, including A*03 (exclusively A*03:01), persistently maintain relatively high CD8 counts following HIV-1 infection, a finding which may offer an intriguing explanation for the recently reported, negative association of A*03 with HIV-1-specific, broadly neutralizing antibody responses. In future studies, attention to HLA-I genotyping data may benefit in-depth understanding of both cellular and humoral immunity, as well as the intrinsic balances of these types of immunity, especially in settings where there is emerging evidence of antagonism between the two arms of adaptive immunity.


2021 ◽  
Author(s):  
Kathryn E. Stephenson ◽  
Boris Julg ◽  
C. Sabrina Tan ◽  
Rebecca Zash ◽  
Stephen R. Walsh ◽  
...  

AbstractHuman immunodeficiency virus (HIV)-1-specific broadly neutralizing monoclonal antibodies are currently under development to treat and prevent HIV-1 infection. We performed a single-center, randomized, double-blind, dose-escalation, placebo-controlled trial of a single administration of the HIV-1 V3-glycan-specific antibody PGT121 at 3, 10 and 30 mg kg–1 in HIV-uninfected adults and HIV-infected adults on antiretroviral therapy (ART), as well as a multicenter, open-label trial of one infusion of PGT121 at 30 mg kg–1 in viremic HIV-infected adults not on ART (no. NCT02960581). The primary endpoints were safety and tolerability, pharmacokinetics (PK) and antiviral activity in viremic HIV-infected adults not on ART. The secondary endpoints were changes in anti-PGT121 antibody titers and CD4+ T-cell count, and development of HIV-1 sequence variations associated with PGT121 resistance. Among 48 participants enrolled, no treatment-related serious adverse events, potential immune-mediated diseases or Grade 3 or higher adverse events were reported. The most common reactions among PGT121 recipients were intravenous/injection site tenderness, pain and headache. Absolute and relative CD4+ T-cell counts did not change following PGT121 infusion in HIV-infected participants. Neutralizing anti-drug antibodies were not elicited. PGT121 reduced plasma HIV RNA levels by a median of 1.77 log in viremic participants, with a viral load nadir at a median of 8.5 days. Two individuals with low baseline viral loads experienced ART-free viral suppression for ≥168 days following antibody infusion, and rebound viruses in these individuals demonstrated full or partial PGT121 sensitivity. The trial met the prespecified endpoints. These data suggest that further investigation of the potential of antibody-based therapeutic strategies for long-term suppression of HIV is warranted, including in individuals off ART and with low viral load.


2001 ◽  
Vol 28 (1) ◽  
pp. 99-101 ◽  
Author(s):  
John N. Nkengasong ◽  
Marie-Yolande Borget ◽  
Chantal Maurice ◽  
Emmanuel Boateng ◽  
Mireille Kalou ◽  
...  

2002 ◽  
Vol 76 (5) ◽  
pp. 2298-2305 ◽  
Author(s):  
Bradley H. Edwards ◽  
Anju Bansal ◽  
Steffanie Sabbaj ◽  
Janna Bakari ◽  
Mark J. Mulligan ◽  
...  

ABSTRACT The importance of CD8+ T-cell responses in the control of human immunodeficiency virus type 1 (HIV-1) infection has been demonstrated, yet few studies have been able to correlate these responses with markers of HIV-1 disease progression. This study measured cell-mediated immune responses using peripheral blood mononuclear cells (PBMC) obtained from 27 patients with chronic HIV-1 infection, the majority of whom were off antiretroviral therapy. The ELISPOT assay was used to detect gamma interferon-secreting PBMC after stimulation with overlapping HIV-1 peptides spanning the Gag, Pol, Env, and Nef proteins in addition to the baculovirus-derived p24 and gp160 proteins. All volunteers had responses to at least one HIV-1-specific peptide. All but one of the subjects (96%) responded to the Gag peptide pool, and 86% responded to the Pol and/or Nef peptide pools. The magnitude and the breadth of T-cell responses directed to either the Gag or p24 peptide pools correlated inversely with viral load in plasma (r = −0.60, P < 0.001 and r = −0.52, P < 0.005, respectively) and directly with absolute CD4+ T-cell counts (r = 0.54, P < 0.01 and r = 0.39, P < 0.05, respectively) using the Spearman rank correlation test. Responses to the Pol and integrase peptide pools also correlated with absolute CD4+ T-cell counts (r = 0.45, P < 0.05 and r = 0.49, P < 0.01, respectively). No correlation with markers of disease progression was seen with specific T-cell responses directed toward the Env or Nef peptides. These data serve as strong evidence that major histocompatibility complex class I presentation of Gag peptides is an essential feature for any HIV-1 vaccine designed to elicit optimal CD8+ T-cell responses.


2003 ◽  
Vol 14 (5) ◽  
pp. 350-355 ◽  
Author(s):  
R Rossero ◽  
D M Asmuth ◽  
J J Grady ◽  
D S McKinsey ◽  
S Green ◽  
...  

The safety and efficacy of hydroxyurea with didanosine in combination with stavudine in nucleoside reverse-transcriptase inhibitor (NRTI)-experienced patients was investigated. Entry criteria included HIV-1 infected, NRTI-experienced adults, with CD4+ counts 50-550 cells/mm3 and viral loads ≥12,500 copies/mL. Subjects were treated with didanosine 200 mg twice a day (BID), stavudine 40 mg BID, and hydroxyurea 1000 mg daily for 16 weeks. Thirty-one HIV-1 subjects with mean bDNA viral load 1×105 log10 copies/mL and mean CD4+ T-cell counts of 231 cells/mm3 were enrolled. A 1.3 log10 decrease in mean viral load was seen at 12 weeks of therapy. Prior didanosine use resulted in a more rapid response to therapy compared with prior zidovudine use. Side effects consisting of neutropenia, pancreatitis, and peripheral neuropathy occurred in four subjects and resolved upon withdrawal of therapy. This non-randomized study in subjects with a mean CD4+ T-cell count of 230 cells/mm3 demonstrates the antiviral activity of hydroxyurea+didanosine and stavudine. Toxicities related to therapy need to be followed closely. The results support the need for a randomized, prospective study to determine the safety and efficacy of hydroxyurea plus didanosine in antiretroviral-experienced patients with CD4+ cell counts below 300 cells/mm3.


2020 ◽  
Vol 14 (1) ◽  
pp. 41-49
Author(s):  
Elidamar Nunes de Carvalho Lima ◽  
Rodrigo Sucupira Andrade Lima ◽  
Muhammad Shoaib Arif ◽  
José Roberto Castilho Piqueira ◽  
Ricardo Sobhie Diaz

Background: The C2V3C3 region of gp 120, encoded by the HIV-1 envelope gene (env), is an important antigenic target, a key determinant for viral evolution and essential for determining epitopes for vaccines. Methods: The relationships among genetic sequence diversity, selective pressure, constraints on HIV-1 envelope protein were explored and also correlated this analysis with information entropy; hypermutation; HIV tropism; CD4+ T cell counts or HIV viral load. A total of 179 HIV-1 C2V3C3 sequences derived from cell-free plasma were used, determined from serial samples, in four epidemiologically linked individuals (one infected blood donor, two transfusion recipients and a sexual partner infected by one of the recipients) over a maximum period of 8 years. This study is important because it considers the analysis of patterns in genomic sequences, without drugs and over time. Results: A temporal relationship among information entropy, hypermutation, tropism switch, viral load, and CD4+ T cell count was determined. Changes in information entropy were time-dependent, and an increase in entropy was observed in the C2V3C3 region at amino acids G313 and F317-I320 (related to the GPGR-motif and coreceptor tropism), and at amino acids A281 in C2 and A346 in C3, related to immune escape. Conclusion: The increase of information entropy over time was correlated with hypermutation and the emergence of nonR5- strains, which are both associated with more variable genomes.


2018 ◽  
Vol 10 (02) ◽  
pp. 162-167
Author(s):  
Sakshee Gupta ◽  
Bharti Malhotra ◽  
Jitendra Kumar Tiwari ◽  
Prabhu Dayal Khandelwal ◽  
Rakesh Kumar Maheshwari

ABSTRACT BACKGROUND: Coinfections of human immunodeficiency virus (HIV) with hepatitis viruses may affect the progress of disease and response to therapy. OBJECTIVES: To study the incidence of hepatitis B virus (HBV) and hepatitis C virus (HCV) coinfections in HIV–positive patients and their influence on HIV–1 viral load and cluster of differentiation 4+ (CD4+) T–cell counts. MATERIALS AND METHODS: This pilot study was done on 179 HIV–positive patients attending antiretroviral therapy (ART) centre. Their blood samples were tested for HIV-1 viral load, CD4+ T–cell counts, hepatitis B surface antigen, anti–HCV antibodies, HBV DNA and HCV RNA polymerase chain reaction. RESULTS: Among the 179 patients, 7.82% (14/179) were coinfected with HBV and 4.46% (8/179) with HCV. Median CD4+ T–cell count of HIV monoinfected patients was 200 cells/µl and viral load was 1.67 log10 copies/µl. Median CD4+ T–cell counts of 193 cells/µl for HBV (P = 0.230) and 197 cells/µl for HCV (P = 0.610) coinfected patients were similar to that of HIV monoinfected patients. Viral load was higher in both HBV and HCV infected patients but statistically significant only for HCV (P = 0.017). Increase in CD4+ T–cell counts and decrease in HIV–1 viral load in coinfected patients on 2 years of ART were lower than that in HIV monoinfected patients. CONCLUSION: HBV/HCV coinfected HIV patients had similar CD4+ T–cell counts as in HIV monoinfected patients, higher HIV viral load both in chemo–naive patients and in those on ART as compared to HIV monoinfected patients. However, this study needs to be done on a large scale to assess the impact of coinfection on CD4 count and HIV viral load with proper follow–up of patients every 6 months till at least 2 years.


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