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Background People with human immunodeficiency virus (HIV) on antiretroviral therapy (ART) with good CD4 T-cell counts make effective immune responses following vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). There are few data on longer term responses and the impact of a booster dose. Methods Adults with HIV were enrolled into a single arm open label study. Two doses of ChAdOx1 nCoV-19 were followed 12 months later by a third heterologous vaccine dose. Participants had undetectable viraemia on ART and CD4 counts >350 cells/µL. Immune responses to the ancestral strain and variants of concern were measured by anti-spike immunoglobulin G (IgG) enzyme-linked immunosorbent assay (ELISA), MesoScale Discovery (MSD) anti-spike platform, ACE-2 inhibition, activation induced marker (AIM) assay, and T-cell proliferation. Findings In total, 54 participants received 2 doses of ChAdOx1 nCoV-19. 43 received a third dose (42 with BNT162b2; 1 with mRNA-1273) 1 year after the first dose. After the third dose, total anti-SARS-CoV-2 spike IgG titers (MSD), ACE-2 inhibition, and IgG ELISA results were significantly higher compared to Day 182 titers (P < .0001 for all 3). SARS-CoV-2 specific CD4+ T-cell responses measured by AIM against SARS-CoV-2 S1 and S2 peptide pools were significantly increased after a third vaccine compared to 6 months after a first dose, with significant increases in proliferative CD4+ and CD8+ T-cell responses to SARS-CoV-2 S1 and S2 after boosting. Responses to Alpha, Beta, Gamma, and Delta variants were boosted, although to a lesser extent for Omicron. Conclusions In PWH receiving a third vaccine dose, there were significant increases in B- and T-cell immunity, including to known variants of concern (VOCs).

Introduction: Variants of the APOL1 gene are associated with chronic kidney disease (CKD) in people of African ancestry, although evidence for their impact in people with HIV are sparse. Methods: We conducted a cross-sectional study investigating the association between APOL1 renal risk alleles and kidney disease in people of African ancestry with HIV in the UK. The primary outcome was end-stage kidney disease (ESKD; estimated glomerular filtration rate [eGFR] of 2, chronic dialysis, or having received a kidney transplant). The secondary outcomes included renal impairment (eGFR 2), albuminuria (albumin-to-creatinine ratio [ACR] >30 mg/mmol), and biopsy-proven HIV-associated nephropathy (HIVAN). Multivariable logistic regression was used to estimate the associations between APOL1 high-risk genotypes (G1/G1, G1/G2, G2/G2) and kidney disease outcomes. Results: A total of 2864 participants (mean age 48.1 [SD 10.3], 57.3% female) were genotyped, of whom, 354 (12.4%) had APOL1 high-risk genotypes, and 99 (3.5%) had ESKD. After adjusting for demographic, HIV, and renal risk factors, individuals with APOL1 high-risk genotypes were at increased odds of ESKD (odds ratio [OR] 10.58, 95% CI 6.22–17.99), renal impairment (OR 5.50, 95% CI 3.81–7.95), albuminuria (OR 3.34, 95% CI 2.00–5.56), and HIVAN (OR 30.16, 95% CI 12.48–72.88). An estimated 49% of ESKD was attributable to APOL1 high-risk genotypes. Conclusion: APOL1 high-risk genotypes were strongly associated with kidney disease in people of African ancestry with HIV and accounted for approximately half of ESKD cases in this cohort.

Despite the success of COVID-19 vaccines in preventing infection and/or severe disease, with the emergence of SARS-CoV-2 variants of concern (VOC) which encode mutations in Spike, and the waning of vaccine induced immunity, there has been an increase in SARS-CoV-2 infections in vaccinated individuals which leads to increased serum neutralization breadth. However, how exposure to a heterologous Spike broadens the neutralizing response at the monoclonal antibody (mAb) level is not fully understood. Through isolation of 119 mAbs from three individuals receiving two-doses of BNT162b2 vaccine before becoming delta or omicron/BA.1-infected, we show that breadth arises from re-activation and maturation of B cells generated through previous COVID-19 vaccination rather than ade novoresponse specific to the VOC Spike. Isolated mAbs frequently show reduced neutralization of current circulating variants including BA.2.75.2, XBB, XBB.1.5 and BQ.1.1 confirming continuous selective pressure on Spike to evolve and evade neutralization. However, isolation of mAbs that display effective cross-neutralization against all variants indicate the presence of conserved epitopes on RBD and a lesser extent NTD. These findings have implications for selection of Spike antigens for next-generation COVID-19 vaccines.

Background: data on vaccine immunogenicity against SARS-CoV-2 are needed for the 40 million people globally living with HIV who might have less functional immunity and more associated comorbidities than the general population. We aimed to explore safety and immunogenicity of the ChAdOx1 nCoV-19 (AZD1222) vaccine in people with HIV. Methods: in this single-arm open-label vaccination substudy within the protocol of the larger phase 2/3 trial COV002, adults aged 18–55 years with HIV were enrolled at two HIV clinics in London, UK. Eligible participants were required to be on antiretroviral therapy (ART), with undetectable plasma HIV viral loads (0·05 for all analyses). Interpretation: in this study of people with HIV, ChAdOx1 nCoV-19 was safe and immunogenic, supporting vaccination for those well controlled on ART. Funding: UK Research and Innovation, National Institutes for Health Research (NIHR), Coalition for Epidemic Preparedness Innovations, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midland's NIHR Clinical Research Network, and AstraZeneca.

Sickle cell trait (SCT) has been associated with chronic kidney disease (CKD) in African Americans, although evidence for its impact in Africans and people with HIV is currently lacking. We conducted a cross-sectional study investigating the association between SCT and kidney disease in people of African ancestry with HIV in the UK.The primary outcome was estimated glomerular filtration rate (eGFR) 60 ml/min per 1.73 mA total of 2895 participants (mean age 48.1 [SD 10.3], 57.2% female) were included, of whom 335 (11.6%) had SCT and 352 (12.2%) had eGFR 60 ml/min per 1.73 mOur results extend previously reported associations between SCT and kidney disease to people with HIV. In people of African ancestry with HIV, these associations were largely restricted to those with

Duration of protection from SARS-CoV-2 infection in people with HIV (PWH) following vaccination is unclear. In a sub-study of the phase 2/3 the COV002 trial (NCT04400838), 54 HIV positive male participants on antiretroviral therapy (undetectable viral loads, CD4+ T cells >350 cells/ul) received two doses of ChAdOx1 nCoV-19 (AZD1222) 4-6 weeks apart and were followed for 6 months. Responses to vaccination were determined by serology (IgG ELISA and MesoScale Discovery (MSD)), neutralisation, ACE-2 inhibition, gamma interferon ELISpot, activation-induced marker (AIM) assay and T cell proliferation. We show that 6 months after vaccination the majority of measurable immune responses were greater than pre-vaccination baseline, but with evidence of a decline in both humoral and cell mediated immunity. There was, however, no significant difference compared to a cohort of HIV-uninfected individuals vaccinated with the same regimen. Responses to the variants of concern were detectable, although were lower than wild type. Pre-existing cross-reactive T cell responses to SARS-CoV-2 spike were associated with greater post-vaccine immunity and correlated with prior exposure to beta coronaviruses. These data support the on-going policy to vaccinate PWH against SARS-CoV-2, and underpin the need for long-term monitoring of responses after vaccination.

Although the antibody response to COVID-19 vaccination has been studied extensively at the polyclonal level using immune sera, little has been reported on the antibody response at the monoclonal level. Here we isolate a panel of 44 anti-SARS-CoV-2 monoclonal antibodies (mAbs) from an individual who received two doses of the ChAdOx1 nCoV-19 (AZD1222) vaccine at a 12-week interval. We show that despite a relatively low serum neutralization titre, mAbs with potent neutralizing activity against the current SARS-CoV-2 variants of concern (B.1.1.7, P.1, B.1.351 and B.1.617.2) were obtained. The vaccine elicited neutralizing mAbs form 8 distinct competition groups and bind epitopes overlapping with neutralizing mAbs elicited following SARS-CoV-2 infection. AZD1222 elicited mAbs are more mutated than mAbs isolated from convalescent donors 1-2 months post infection. Spike reactive IgG+ B cells were still detectable 9-months post boost. These findings give molecular insights into AZD1222 elicited antibody response.

Although the antibody response to COVID-19 vaccination has been studied extensively at the polyclonal level using immune sera, little has been reported on the antibody response at the monoclonal level. Here, we isolate a panel of 44 anti-SARS-CoV-2 monoclonal antibodies (mAbs) from an individual who received two doses of the ChAdOx1 nCoV-19 (AZD1222) vaccine at a 12-week interval. We show that, despite a relatively low serum neutralization titer, Spike-reactive IgG+ B cells are still detectable 9 months post-boost. Furthermore, mAbs with potent neutralizing activity against the current SARS-CoV-2 variants of concern (Alpha, Gamma, Beta, Delta, and Omicron) are present. The vaccine-elicited neutralizing mAbs form eight distinct competition groups and bind epitopes overlapping with neutralizing mAbs elicited following SARS-CoV-2 infection. AZD1222-elicited mAbs are more mutated than mAbs isolated from convalescent donors 1-2 months post-infection. These findings provide molecular insights into the AZD1222 vaccine-elicited antibody response.

We identified a novel HLA A*6801-restricted HIV-1 Tat-derived cytotoxic T lymphocyte (CTL) epitope using an adapted enzyme-linked immunospot assay that allows the rapid ex vivo identification of CTL epitopes together with their associated HLA Class I restriction elements. The optimal 11 amino acid residue Tat epitope efficiently stabilized the refolding of monomeric peptide-HLA A6801 complexes in vitro and fluorochrome-labelled, tetrameric peptide-HLA A6801 complexes stained CD8 T cells specific for this epitope directly ex vivo.

The use of peptide-human histocompatibility leukocyte antigen (HLA) class I tetrameric complexes to identify antigen-specific CD8(+) T cells has provided a major development in our understanding of their role in controlling viral infections. However, questions remain about the exact function of these cells, particularly in HIV infection. Virus-specific cytotoxic T lymphocytes exert much of their activity by secreting soluble factors such as cytokines and chemokines. We describe here a method that combines the use of tetramers and intracellular staining to examine the functional heterogeneity of antigen-specific CD8(+) T cells ex vivo. After stimulation by specific peptide antigen, secretion of interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, macrophage inflammatory protein (MIP)-1beta, and perforin is analyzed by FACS((R)) within the tetramer-positive population in peripheral blood. Using this method, we have assessed the functional phenotype of HIV-specific CD8(+) T cells compared with cytomegalovirus (CMV)-specific CD8(+) T cells in HIV chronic infection. We show that the majority of circulating CD8(+) T cells specific for CMV and HIV antigens are functionally active with regards to the secretion of antiviral cytokines in response to antigen, although a subset of tetramer-staining cells was identified that secretes IFN-gamma and MIP-1beta but not TNF-alpha. However, a striking finding is that HIV-specific CD8(+) T cells express significantly lower levels of perforin than CMV-specific CD8(+) T cells. This lack of perforin is linked with persistent CD27 expression on HIV-specific cells, suggesting impaired maturation, and specific lysis ex vivo is lower for HIV-specific compared with CMV-specific cells from the same donor. Thus, HIV-specific CD8(+) T cells are impaired in cytolytic activity.

The cytotoxic potential of CD8+ T cells and NK cells plays a crucial role in the immune response to pathogens. Although in vitro studies have reported that CD4+ T cells are also able to mediate perforin-mediated killing, the in vivo existence and relevance of cytotoxic CD4+ T cells have been the subject of debate. Here we show that a population of CD4+ perforin+ T cells is present in the circulation at low numbers in healthy donors and is markedly expanded in donors with chronic viral infections, in particular HIV infection, at all stages of the disease, including early primary infection. Ex vivo analysis shows that these cells have cytotoxic potential mediated through the release of perforin. In comparison with more classical CD4+ T cells, this subset displays a distinct surface phenotype and functional profile most consistent with end-stage differentiated T cells and include Ag experienced CD4+ T cells. The existence of CD4+ cytotoxic T cells in vivo at relatively high levels in chronic viral infection suggests a role in the immune response.

HIV immunity is likely CD4 T cell dependent. HIV-specific CD4 T cell proliferative responses are reported to correlate inversely with virus load and directly with specific CD8 responses. However, the phenotype and cytokine profile of specific CD4 T cells that correlate with disease is unknown. We compared the number/function of Gag p24-specific CD4 T cells in 17 HIV-infected long-term nonprogressors (LTNPs) infected for a median of 14.6 years with those of 16 slow progressors (SPs), also HIV infected for a median of 14 years but whose CD4 count had declined to

Summary The mechanisms underlying non-progression in HIV-1 infection are not well understood; however, this state has been associated previously with strong HIV-1-specific CD8+ T cell responses and the preservation of proliferative CD4+ T cell responses to HIV-1 antigens. Using a combination of interferon-gamma (IFN-γ) ELISpot assays and tetramer staining, the HIV-1-specific CD8+ T cell populations were quantified and characterized in untreated long-term HIV-1-infected non-progressors and individuals with slowly progressive disease, both in relation to CD4+ T cell responses, and in comparison with responses to cytomegalovirus (CMV) antigens. High levels of CD8+ T cell responses specific for HIV-1 or CMV were observed, but neither their frequency nor their phenotype seemed to differ between the two patient groups. Moreover, while CMV-specific CD4+ T cell responses were preserved in these donors, IFN-γ release by HIV-1-specific CD4+ T cells was generally low. These data raise questions with regard to the role played by CD8+ T cells in the establishment and maintenance of long-term non-progression.

To determine the prevalence and prognostic significance of intermittent viraemia (IV) in patients who attained an undetectable viral load (VL)400 copies/ml within 6 months on highly active antiretroviral therapy (HAART).Retrospective analysis of viral load reboundor = 400 copies/ml and CD4 cell counts rise for 765 patients followed foror = 12 months following initial VL undetectability, comparing the 226 (29.5%) who maintained an undetectable VL for1 year from initiation of HAART and 122 (15.9%) who had one or more episodes of IV. Genotypic resistance was evaluated at the time of the first episode of IVor = 2000 copies/ml.Patients with IV had a threefold higher rate of sustained virological rebound [hazards ratio (HR), 3.15; 95% confidence interval (CI), 1.72-5.77; P0.001). For patients with and without IV, the Kaplan-Meier estimates at 24 and 36 months after initiation of HAART were 19.3% (95% CI, 8.9-21.5) versus 7.7% (95% CI, 4.5-13.0) and 31.6% (95% CI, 21.8-44.2) versus 12.9% (95% CI, 7.5-21.5), respectively (P0.001). The median CD4 cell count rise at 18 and 24 months was significantly lower in those with IV than in those without: 138 [interquartile range (IQR), 58-221] versus 224 x 10(6) cells/l (IQR, 119-357) (P = 0.0001) and 200 (IQR, 89-294) versus 260 x 10(6) cells/l (IQR, 125-384) (P = 0.003), respectively. In a subgroup of 16 patients, genotypic resistance mutations were found in the reverse transcriptase gene for five (31%) and in the protease gene in one. A probable contributing factor/event was identified for most patients with IV, such as poor adherence (42.6%), intercurrent infection (26.2%) or drug interaction (6.8%).Patients with IV400 copies/ml are three times more likely to experience sustained viral rebound and to have an impaired CD4 cell rise relative to those who maintain undetectable VL. This supports the adoption of a more pro-active approach to treatment intensification and the need for caution with structured treatment interruptions.

We describe an unusual pathway of human immunodeficiency virus type 1 reverse transcriptase resistance during therapy with tenofovir-emtricitabine, characterized initially by the mutations K70E and M184V and later by K70G and M184V, with the two mutations coexisting on the same viral genome. Phenotypic resistance to lamivudine, emtricitabine, abacavir, didanosine, and tenofovir was observed, whereas susceptibility to zidovudine and stavudine was preserved.

The outcome of human immunodeficiency virus type 1 (HIV-1) infection is related to the set-point plasma virus load (pVL) that emerges after primary HIV-1 infection ( PHI). This set-point pVL generally remains stable but eventually increases with progression to disease. However, the events leading to loss of viremic control are poorly understood. Here, we describe an individual who presented with symptomatic PHI and subsequently progressed rapidly, after an initial period of 1 year during which viral replication was well controlled. Escalation of viral replication in this atypical case was preceded by the emergence of escape variants in many epitopes targeted by dominant CD8(+) T cell responses and a marked decrease in HIV-1-specific CD4(+) and CD8(+) T cell frequencies. There were no changes in viral tropism, replication kinetics, or neutralizing antibody titers. These findings demonstrate the temporal relationship between viral escape from CD8(+) T cell activity, decrease in HIV-1-specific T cell frequencies, and loss of control of viral replication.

Progress in the fight against the HIV/AIDS epidemic is hindered by our failure to elucidate the precise reasons for the onset of immunodeficiency in HIV-1 infection. Increasing evidence suggests that elevated immune activation is associated with poor outcome in HIV-1 pathogenesis. However, the basis of this association remains unclear. Through ex vivo analysis of virus-specific CD8(+) T-cells and the use of an in vitro model of naïve CD8(+) T-cell priming, we show that the activation level and the differentiation state of T-cells are closely related. Acute HIV-1 infection induces massive activation of CD8(+) T-cells, affecting many cell populations, not only those specific for HIV-1, which results in further differentiation of these cells. HIV disease progression correlates with increased proportions of highly differentiated CD8(+) T-cells, which exhibit characteristics of replicative senescence and probably indicate a decline in T-cell competence of the infected person. The differentiation of CD8(+) and CD4(+) T-cells towards a state of replicative senescence is a natural process. It can be driven by excessive levels of immune stimulation. This may be part of the mechanism through which HIV-1-mediated immune activation exhausts the capacity of the immune system., Journal Article, Research Support, N.I.H. Extramural, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S., Review, info:eu-repo/semantics/published

AIM To characterize HIV-1 Gag p24-specific CD4 cell responses in HIV-exposed-seronegative (ES) individuals. METHODOLOGY Twelve ES individuals, of diverse ethnicity and wild type for the CCR5 Delta-32 mutation, were identified. Controls were HIV-negative blood donors. Gag p24-specific and total Vbeta+ CD4 cells that expressed MIP-1beta, IFN-gamma and IL-2 were enumerated by intracytoplasmic cytokine staining. beta-Chemokine expression was correlated with susceptibility to R5 HIV-1 infection, as measured by polymerase chain reaction for integrated HIV-1 and by p24 enzyme-linked immunosorbent assay. RESULTS Similar numbers of mitogen-stimulated and Vbeta+ MIP-1beta+, IFN-gamma+ and IL-2+ T cells were found in ES and HIV-negative control subjects. However, all ES subjects tested had an HIV Gag p24-specific MIP-1beta+, IFN-gamma+ and IL-2+ CD4 T-cell response that was rare in controls. p24-Specific cells of all ES but no control subjects could be expanded by in-vitro Ag/IL-2 stimulation, and when re-stimulated with an overlapping peptide series showed evidence of a broad CD4 cell memory response directed against multiple regions of Gag p24. Mitogen-stimulated ES CD4 cells were as susceptible to HIV infection as those from control subjects, but p24-specific IFN-gamma+ CD4 cells of six out of seven ES subjects tested were less susceptible to R5 HIV-1 infection than the counterpart fraction depleted of p24-specific IFN-gamma+ cells. The addition of blocking anti-beta-chemokine antibodies did not promote R5 HIV-1 infection of p24-specific IFN-gamma+ cells. CONCLUSION Specific CD4 cell immunity, characterized by a broadly directed memory Gag-p24 CD4 cell response and reduced susceptibility of specific CD4 cells to R5 HIV-1 infection, is a likely correlate of non-transmission.

The viruses HIV-1, Epstein-Barr virus (EBV), cytomegalovirus (CMV) and hepatitis C virus (HCV) are characterized by the establishment of lifelong infection in the human host, where their replication is thought to be tightly controlled by virus-specific CD8+ T cells. Here we present detailed studies of the differentiation phenotype of these cells, which can be separated into three distinct subsets based on expression of the costimulatory receptors CD28 and CD27. Whereas CD8+ T cells specific for HIV, EBV and HCV exhibit similar characteristics during primary infection, there are significant enrichments at different stages of cellular differentiation in the chronic phase of persistent infection according to the viral specificity, which suggests that distinct memory T-cell populations are established in different virus infections. These findings challenge the current definitions of memory and effector subsets in humans, and suggest that ascribing effector and memory functions to subsets with different differentiation phenotypes is no longer appropriate.

M Ramaswamy1, A Waters1,2, E Hainsworth1, C Smith1, G Hardy1, M Johnson1, JAinsworth2, A Phillips1, and Anna Maria GerettiAuthor Email1 1Royal Free and Univ Coll Med Sch, London, UK and 2North Middlesex Hosp, London,UK Conf Retrovir Opportunistic Infect 2006 Feb 5-8;13:abstract no. 786 February 5, 2006 BACKGROUND: Secretion of interferon-gamma (IFN-γ) by activated T cells has beenproposed as a key protective mechanism against herpes simplex virus (HSV) infection.We reported previously that the clinical expression of HSV infection declined in HIV-infected patients after the introduction of HAART, suggesting restoration ofimmunologic control. Our aim here was to study HSV-specific T-cell immunity inperipheral blood of HIV-infected persons at different disease stages.METHODS: We investigated 4 HIV-infected groups: A) long-term slow/non-progressors(LTSP/LTNP) with CD4 >450 cells/mm3 over ≥10 years, sampled at 3 time points; B)newly diagnosed patients; C) patients stable on HAART; D) patients starting HAARTsampled prospectively. Control groups: HSV IgG seropositive (HSV+) andseronegative (HSV-) healthy donors sampled at 3 time points and HSV- HIV-infectedpersons with CD4 >250. IFN-γ production of fresh peripheral blood mononuclear cells(PBMC) (triplicate wells) stimulated with HSV-1 and HSV-2 lysates (1, 5, and 10µg/mL) were assayed by ELISpot. The mean number of spot-forming cells (SFCn) per106 PBMC was determined by an automated reader. Responses were furthercharacterised by intracellular cytokine staining (ICS).RESULTS: SFCn was 320±90 in HSV+ healthy donors (n = 11) and 28±11 in HSV-donors (n = 9); responses were stable over 9 weeks. SFCn was 30±18 in HSV- HIV-infected persons (n = 10, median CD4 457). SFCn of HSV+ HIV-infected persons was:A) LTSP/LTNP (n = 3, median CD4 953): 334±82, stable over ≤43 weeks. B) newlydiagnosed patients (n = 9, median CD4 453): 186±51. C) patients on stable HAART (n= 33, median CD4 360, 91% with viral load