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Twelve weeks of dipyridamole increased extracellular adenosine levels and decreased T cell activation in people with HIV. In this analysis, we investigated the effect of dipyridamole on HIV-specific T cell responses. We compared changes in Gag- and Env-specific T cell responses using intracellular cytokine staining, following 12 weeks of dipyridamole treatment vs placebo. We evaluated whether frequencies of polyfunctional HIV-specific T cells were associated with purines in the adenosine pathway and with measures of HIV persistence and chronic inflammation. There was a significant decrease in CD4+ polyfunctional T cell responses to Gag (-62.6% vs -23.0%; p<0.001) and Env (-56.1% vs -6.0%; p<0.001) in the dipyridamole arm. In the dipyridamole group, lower frequencies of polyfunctional Env-specific CD4+ T cells were associated with higher plasma levels of adenosine (r= -0.85; p<0.01) and inosine (r= -0.70; p=0.04). Higher adenosine levels induced by dipyridamole treatment is associated with decreased HIV-specific CD4+ T cell polyfunctional responses in people with HIV on antiretroviral therapy.
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Background: T cells in people with human immunodeficiency virus (HIV) demonstrate an exhausted phenotype, and HIV-specific CD4+ T cells expressing programmed cell death 1 (PD-1) are enriched for latent HIV, making antibody to PD-1 a potential strategy to target the latent reservoir. Methods: This was a phase 1/2, randomized (4:1), double-blind, placebo-controlled study in adults with suppressed HIV on antiretroviral therapy with CD4+ counts ≥350 cells/µL who received 2 infusions of cemiplimab versus placebo. The primary outcome was safety, defined as any grade 3 or higher adverse event (AE) or any immune-related AE (irAE). Changes in HIV-1-specific polyfunctional CD4+ and CD8+ T-cell responses were evaluated. Results: Five men were enrolled (median CD4+ count, 911â cells/µL; median age, 51 years); 2 received 1 dose of cemiplimab, 2 received 2 doses, and 1 received placebo. One participant had a probable irAE (thyroiditis, grade 2); another had a possible irAE (hepatitis, grade 3), both after a single low-dose (0.3 mg/kg) infusion. The Safety Monitoring Committee recommended no further enrollment or infusions. All 4 cemiplimab recipients were followed for 48 weeks. No other cemiplimab-related serious AEs, irAEs, or grade 3 or higher AEs occurred. One 2-dose recipient of cemiplimab had a 6.2-fold increase in polyfunctional, Gag-specific CD8+ T-cell frequency with supportive increases in plasma HIV RNA and decreases in total HIV DNA. Conclusions: One of 4 participants exhibited increased HIV-1-specific T-cell responses and transiently increased HIV-1 expression following 2 cemiplimab infusions. The occurrence of irAEs after a single, low dose may limit translating the promising therapeutic results of cemiplimab for cancer to immunotherapeutic and latency reversal strategies for HIV. Clinical Trials Registration. NCT03787095.
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BACKGROUND: Improved COVID-19 prevention is needed for immunocompromised individuals. METHODS: Prospective study of healthcare workers (HCW) and immunocompromised participants with baseline serology following 2 mRNA vaccines and who were retested after dose 3 (D3); multivariable regression was used to identify predictors of serological responses. IFNγ/TNFα T-cell responses were assessed in a subset. RESULTS: 536 participants were included: 492 immunocompromised [(206 solid organ transplant (SOT), 128 autoimmune, 80 hematologic malignancy (HM), 48 solid tumor, 25 HIV], 44 HCW. D3 significantly increased Spike IgG levels among all, but SOT and HM participants had the lowest median antibody levels post-D3 (increase from 0.09 to 0.83 and 0.27 to 1.92, respectively), versus HCW and persons with HIV, autoimmune conditions, and solid tumors (increases from 4.44 to 19.79, 2.9 to 15.75, 3.82 to 16.32, and 4.1 to 25.54, respectively). Seropositivity post-D3 was lowest for SOT (49.0%) and HM (57.8%), versus others (>90% seropositive). Neutralization post-D3 was lowest among SOT and HM. Predictors of lower antibody levels included low baseline levels and shorter intervals between vaccines. T-cell responses against Spike increased significantly among HCW and non-significantly among immunocompromised individuals. CONCLUSIONS: D3 significantly improves serological but not T-cell responses among immunocompromised individuals. SOT and HM patients have suboptimal responses to D3.
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Prolonged coronavirus disease 2019 may generate new viral variants. We report an immunocompromised patient treated with monoclonal antibodies who experienced rebound of viral RNA and emergence of an antibody-resistant (>1000-fold) variant containing 5 mutations in the spike gene. The mutant virus was isolated from respiratory secretions, suggesting the potential for secondary transmission.
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TIM-3 expression is increased on peripheral regulatory T cells (Tregs) of virally suppressed persons with HIV-1 on antiretroviral therapy (PWH-ART). However, the relevance of TIM-3 expression in this setting is unclear. We used flow cytometry to evaluate the suppressive phenotype and signaling pathways in peripheral TIM-3- vs TIM-3+ Tregs in PWH-ART. TIM-3+ Tregs showed increased expression of IL-10 compared with persons without HIV-1. In addition, TIM-3+ Tregs displayed elevated signaling and activation, relative to TIM-3- Tregs from the same PWH-ART. Dramatically, TIM-3 blockade restrained the in vitro suppressive capacity of peripheral Tregs. Therefore, our data demonstrate not only that TIM-3 expression by Tregs is associated with an immunosuppressive response among PWH-ART, but also that TIM-3 contributes directly to the enhanced suppressive activity of Tregs in this setting.
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Infecções por HIV , Receptor Celular 2 do Vírus da Hepatite A , Humanos , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Linfócitos T Reguladores/metabolismo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/metabolismoRESUMO
BACKGROUND: Neurocognitive impairment (NCI) in people with HIV (PWH) on antiretroviral therapy (ART) is common and may result from persistent HIV replication in the central nervous system. METHODS: A5324 was a randomized, double-blind, placebo-controlled, 96-week trial of ART intensification with dolutegravir (DTG) + MVC, DTG + Placebo, or Dual - Placebo in PWH with plasma HIV RNA <50 copies/mL on ART and NCI. The primary outcome was the change on the normalized total z score (ie, the mean of individual NC test z scores) at week 48. RESULTS: Of 357 screened, 191 enrolled: 71% male, 51% Black race, 22% Hispanic ethnicity; mean age 52 years; mean CD4+ T-cells 681 cells/µL. Most (65%) had symptomatic HIV-associated NC disorder. Study drug was discontinued due to an adverse event in 15 (8%) and did not differ between arms (P = .17). Total z score, depressive symptoms, and daily functioning improved over time in all arms with no significant differences between them at week 48 or later. Adjusting for age, sex, race, study site, efavirenz use, or baseline z score did not alter the results. Body mass index modestly increased over 96 weeks (mean increase 0.32 kg/m2, P = .006) and did not differ between arms (P > .10). CONCLUSIONS: This is the largest, randomized, placebo-controlled trial of ART intensification for NCI in PWH. The findings do not support empiric ART intensification as a treatment for NCI in PWH on suppressive ART. They also do not support that DTG adversely affects cognition, mood, or weight.
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Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Terapia Antirretroviral de Alta Atividade/métodos , HIV-1/genética , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Fármacos Anti-HIV/uso terapêutico , Linfócitos T CD4-Positivos , Carga ViralRESUMO
We administered severe acute respiratory syndrome coronavirus-2 viral-specific T cells (VSTs) under emergency investigational new drug applications to 6 immunocompromised patients with persistent coronavirus disease 2019 (COVID-19) and characterized clinical and virologic responses. Three patients had partial responses after failing other therapies but then died. Two patients completely recovered, but the role of VSTs in recovery was unclear due to concomitant use of other antivirals. One patient had not responded to 2 courses of remdesivir and experienced sustained recovery after VST administration. The use of VSTs in immunocompromised patients with persistent COVID-19 requires further study.
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COVID-19 , Transplante de Células-Tronco Hematopoéticas , Humanos , SARS-CoV-2 , Linfócitos T , Hospedeiro ImunocomprometidoRESUMO
Acute kidney injury (AKI) is common in patients hospitalized for COVID-19, complicating their clinical course and contributing to worse outcomes. Animal studies show that adenosine, inosine and guanosine protect the kidney against some types of AKI. However, until now there was no evidence in patients supporting the possibility that abnormally low kidney levels of adenosine, inosine and guanosine contribute to AKI. Here, we addressed the question as to whether these renoprotective purines are altered in the urine of COVID-19 patients with AKI. Purines were measured by employing ultra-high-performance liquid chromatography-tandem mass spectrometry with stable-isotope-labeled internal standards for each purine of interest. Compared with COVID-19 patients without AKI (n = 23), COVID-19 patients with AKI (n = 20) had significantly lower urine levels of adenosine (P < 0.0001), inosine (P = 0.0008), and guanosine (P = 0.0008) (medians reduced by 85%, 48% and 61%, respectively) and lower levels (P = 0.0003; median reduced by 67%) of the 2nd messenger for A2A and A2B adenosine receptors, i.e., 3',5'-cAMP. Moreover, in COVID-19 patients with AKI, urine levels of 8-aminoguanine (endogenous inhibitor of inosine and guanosine metabolism) were nearly abolished (P < 0.0001). In contrast, the "upstream" precursors of renoprotective purines, namely 5'-AMP and 5'-GMP, were not significantly altered in COVID-19 patients with AKI, suggesting defective conversion of these precursors by CD73 (converts 5'-AMP to adenosine and 5'-GMP to guanosine). These findings imply that an imbalance in renoprotective purines may contribute to AKI in COVID-19 patients and that pharmacotherapy targeted to restore levels of renoprotective purines may attenuate the risk of AKI in susceptible patients with COVID-19.
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Injúria Renal Aguda , COVID-19 , Adenosina , Monofosfato de Adenosina , Animais , Guanosina/metabolismo , Guanosina Monofosfato , Inosina/metabolismo , Purinas/metabolismoRESUMO
BACKGROUND: Excessive complement activation has been implicated in the pathogenesis of coronavirus disease 2019 (COVID-19), but the mechanisms leading to this response remain unclear. METHODS: We measured plasma levels of key complement markers, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA and antibodies against SARS-CoV-2 and seasonal human common cold coronaviruses (CCCs) in hospitalized patients with COVID-19 of moderate (nâ =â 18) and critical severity (nâ =â 37) and in healthy controls (nâ =â 10). RESULTS: We confirmed that complement activation is systemically increased in patients with COVID-19 and is associated with a worse disease outcome. We showed that plasma levels of C1q and circulating immune complexes were markedly increased in patients with severe COVID-19 and correlated with higher immunoglobulin (Ig) G titers, greater complement activation, and higher disease severity score. Additional analyses showed that the classical pathway was the main arm responsible for augmented complement activation in severe patients. In addition, we demonstrated that a rapid IgG response to SARS-CoV-2 and an anamnestic IgG response to the nucleoprotein of the CCCs were strongly correlated with circulating immune complex levels, complement activation, and disease severity. CONCLUSIONS: These findings indicate that early, nonneutralizing IgG responses may play a key role in complement overactivation in severe COVID-19. Our work underscores the urgent need to develop therapeutic strategies to modify complement overactivation in patients with COVID-19.
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COVID-19 , Anticorpos Antivirais , Proteínas do Nucleocapsídeo de Coronavírus , Humanos , Imunoglobulina G , SARS-CoV-2RESUMO
BACKGROUND: We studied humoral responses after coronavirus disease 2019 (COVID-19) vaccination across varying causes of immunodeficiency. METHODS: Prospective study of fully vaccinated immunocompromised adults (solid organ transplant [SOT], hematologic malignancy, solid cancers, autoimmune conditions, human immunodeficiency virus [HIV]) versus nonimmunocompromised healthcare workers (HCWs). The primary outcome was the proportion with a reactive test (seropositive) for immunoglobulin G to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor-binding domain. Secondary outcomes were comparisons of antibody levels and their correlation with pseudovirus neutralization titers. Stepwise logistic regression was used to identify factors associated with seropositivity. RESULTS: A total of 1271 participants enrolled: 1099 immunocompromised and 172 HCW. Compared with HCW (92.4% seropositive), seropositivity was lower among participants with SOT (30.7%), hematological malignancies (50.0%), autoimmune conditions (79.1%), solid tumors (78.7%), and HIV (79.8%) (P < .01). Factors associated with poor seropositivity included age, greater immunosuppression, time since vaccination, anti-CD20 monoclonal antibodies, and vaccination with BNT162b2 (Pfizer) or adenovirus vector vaccines versus messenger RNA (mRNA)-1273 (Moderna). mRNA-1273 was associated with higher antibody levels than BNT162b2 or adenovirus vector vaccines after adjusting for time since vaccination, age, and underlying condition. Antibody levels were strongly correlated with pseudovirus neutralization titers (Spearman râ =â 0.89, Pâ <â .0001), but in seropositive participants with intermediate antibody levels, neutralization titers were significantly lower in immunocompromised individuals versus HCW. CONCLUSIONS: Antibody responses to COVID-19 vaccines were lowest among SOT and anti-CD20 monoclonal recipients, and recipients of vaccines other than mRNA-1273. Among those with intermediate antibody levels, pseudovirus neutralization titers were lower in immunocompromised patients than HCWs. Additional SARS-CoV-2 preventive approaches are needed for immunocompromised persons, which may need to be tailored to the cause of immunodeficiency.
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COVID-19 , Infecções por HIV , Adulto , Anticorpos Antivirais , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Infecções por HIV/complicações , Humanos , Hospedeiro Imunocomprometido , Estudos Prospectivos , SARS-CoV-2 , VacinaçãoAssuntos
Infecções por HIV/tratamento farmacológico , Inibidores de Checkpoint Imunológico/efeitos adversos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Contagem de Linfócito CD4 , Método Duplo-Cego , Infecções por HIV/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , PlacebosRESUMO
A chimeric antigen receptor-modified T-cell therapy recipient developed severe coronavirus disease 2019, intractable RNAemia, and viral replication lasting >2 months. Premortem endotracheal aspirate contained >2 × 1010 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA copies/mL and infectious virus. Deep sequencing revealed multiple sequence variants consistent with intrahost virus evolution. SARS-CoV-2 humoral and cell-mediated immunity were minimal. Prolonged transmission from immunosuppressed patients is possible.
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COVID-19 , Receptores de Antígenos Quiméricos , Terapia Baseada em Transplante de Células e Tecidos , Humanos , SARS-CoV-2 , Replicação ViralRESUMO
BACKGROUND: We had previously conducted a double-blind, randomized placebo-controlled, partial cross-over trial showing that 12 weeks of dipyridamole decreased CD8 T-cell activation among treated HIV(+) individuals by increasing extracellular adenosine levels. METHODS: In this substudy, rectosigmoid biopsies were obtained from 18 participants (9 per arm), to determine whether 12 weeks of dipyridamole affects mucosal immune cells. Participants randomized to placebo were then switched to dipyridamole for 12 weeks while the treatment arm continued dipyridamole for another 12 weeks. We evaluated T-cell frequencies and plasma markers of microbial translocation and intestinal epithelial integrity. Linear regression models on log-transformed outcomes were used for the primary 12-week analysis. RESULTS: Participants receiving dipyridamole had a median 70.2% decrease from baseline in regulatory T cells (P = 0.007) and an 11.3% increase in CD8 T cells (P = 0.05). There was a nonsignificant 10.80% decrease in plasma intestinal fatty acid binding protein levels in the dipyridamole arm compared with a 9.51% increase in the placebo arm. There were no significant differences in plasma levels of ß-D-glucan. In pooled analyses, there continued to be a significant decrease in regulatory T cells (-44%; P = 0.004). There was also a trend for decreased CD4 and CD8 T-cell activation. CONCLUSION: Increasing extracellular adenosine levels using dipyridamole in virally suppressed HIV (+) individuals on antiretroviral therapy can affect regulation of gut mucosal immunity.
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Fármacos Anti-HIV/uso terapêutico , Dipiridamol/farmacologia , Infecções por HIV/tratamento farmacológico , Mucosa Intestinal/efeitos dos fármacos , Linfócitos T Reguladores/efeitos dos fármacos , Adenosina/metabolismo , Biópsia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Estudos Cross-Over , Feminino , Citometria de Fluxo , Humanos , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Ativação Linfocitária/efeitos dos fármacos , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: The objective of this study was to investigate whether 100% antiretroviral therapy (ART) adherence in men with HIV (MWH) is associated with normalization of concentrations of biomarkers of inflammation and immune activation compared with HIV-uninfected men. METHODS: We analyzed person-visits with available biomarker data from the Multicenter AIDS Cohort Study (MACS) among MWH receiving ART with HIV RNAâ <50 copies/mL and among HIV-uninfected men. Self-reported adherence was classified as 100% if no missed ART doses in the past 4 days were reported. We evaluated associations between ART adherence and concentrations of 24 serum biomarkers compared with HIV-uninfected visits using a generalized gamma model, adjusting for potential confounders. RESULTS: Person-visits (2565 from MWH reporting 100% ART adherence and 1588 from HIV-uninfected men) from a total of 1469 men were included in the analysis. Serum concentrations of interleukin-6 (IL-6), soluble interleukin-6 receptor (sIL-6R), IL-1ß, interferon-γ (IFN-γ), chemokine C-C motif ligand 2 (CCL2), and CCL14 from person-visits among MWH who reported 100% adherence were similar to HIV-uninfected person-visits. Comparatively higher concentrations of 11 biomarkers and lower concentrations of 7 biomarkers were observed in person-visits from MWH who reported 100% ART adherence, compared with HIV-uninfected person-visits. CONCLUSIONS: Although MWH with virologic suppression who reported 100% ART adherence exhibited overall higher concentrations of biomarkers of inflammation and immune activation compared with HIV-uninfected men, some biomarker concentrations were similar in both groups. These findings suggest that optimal ART adherence could have clinical implications beyond achieving and sustaining viral suppression.
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BACKGROUND: Adenosine is a potent immunoregulatory nucleoside produced during inflammatory states to limit tissue damage. We hypothesized that dipyridamole, which inhibits cellular adenosine uptake, could raise the extracellular adenosine concentration and dampen chronic inflammation associated with human immunodeficiency virus (HIV) type 1. METHODS: Virally suppressed participants receiving antiretroviral therapy were randomized 1:1 for 12 weeks of dipyridamole (100 mg 4 times a day) versus placebo capsules. All participants took open-label dipyridamole during weeks 12-24. Study end points included changes in markers of systemic inflammation (soluble CD163 and CD14, and interleukin 6) and levels of T-cell immune activation (HLA-DR+CD38+). RESULTS: Of 40 participants who were randomized, 17 dipyridamole and 18 placebo recipients had baseline and week 12 data available for analyses. There were no significant changes in soluble markers, apart from a trend toward decreased levels of soluble CD163 levels (P = .09). There was a modest decrease in CD8+ T-cell activation (-17.53% change for dipyridamole vs +13.31% for placebo; P = .03), but the significance was lost in the pooled analyses (P = .058). Dipyridamole also reduced CD4+ T-cell activation (-11.11% change; P = .006) in the pooled analyses. In post hoc analysis, detectable plasma dipyridamole levels were associated with higher levels of inosine, an adenosine surrogate, and of cyclic adenosine monophosphate. CONCLUSION: Dipyridamole increased extracellular adenosine levels and decreased T-cell activation significantly among persons with HIV-1 infection receiving virally suppressive therapy.
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Dipiridamol/uso terapêutico , Infecções por HIV/complicações , Inflamação/tratamento farmacológico , Inflamação/etiologia , Inibidores de Fosfodiesterase/uso terapêutico , Adolescente , Adulto , Biomarcadores/sangue , Doença Crônica , Método Duplo-Cego , Infecções por HIV/tratamento farmacológico , HIV-1 , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Adulto JovemRESUMO
OBJECTIVE: We evaluated frequencies of T cells with high PD-1 expression (PD-1) before and after long-term effective antiretroviral therapy (ART), and determined if frequencies on-ART correlated positively with measures of HIV persistence and negatively with HIV-specific responses. METHODS: We enrolled individuals who started ART during chronic infection and had durable suppression of viremia for at least 4 years (Nâ=â99). We assessed PD-1 T-cell frequencies at timepoints pre-ART and on-ART using flow cytometry, and evaluated how frequencies on-ART are associated with measures of HIV persistence, HIV-specific immune responses, and immune activation levels. RESULTS: Pre-ART, PD-1 CD4 T cells correlated positively with viremia and negatively with CD4 T-cell count. At year 1 on-ART, %PD-1 CD4 T cells decreased but then remained stable at 4 and 6-15 years on-ART, whereas %PD-1 CD8 T cells on-ART remained similar to pre-ART. PD-1 CD4 T cells correlated positively with HIV DNA pre-ART and on-ART, and with CD4 T-cell activation on-ART. PD-1 CD4 T cells negatively correlated with HIV Gag-specific and Env-specific T-cell responses but not with CMV-specific or EBV-specific responses. PD-1 CD8 T cells trended towards a negative correlation with responses to Gag and Env, but not to CMV and EBV. CONCLUSION: PD-1 T cells persist in blood despite prolonged suppression on ART, correlate with HIV DNA levels, and are associated with lower HIV-specific T-cell responses but not CMV-specific or EBV-specific responses, suggesting that these cells are HIV-specific. The findings support evaluating PD-1 blockade strategies for their effect on HIV persistence and HIV-specific immunity.
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Contagem de Linfócito CD4 , Infecções por HIV/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologia , Adulto , Fármacos Anti-HIV/uso terapêutico , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Carga ViralRESUMO
Eliciting highly functional CD8+ cytotoxic T lymphocyte (CTL) responses against a broad range of epitopes will likely be required for immunotherapeutic control of HIV-1 infection. However, the combination of CTL exhaustion and the ability of HIV-1 to rapidly establish CTL escape variants presents major hurdles toward this goal. Our previous work highlighted the use of monocyte-derived, mature, high-interleukin-12 (IL-12)-producing type 1 polarized dendritic cells (MDC1) to selectively induce more potent effector CTLs derived from naive, rather than memory, CD8+ T cell precursors isolated from HIV-1-positive participants in the Multicenter AIDS Cohort Study. In this study, we report that these highly stimulatory antigen-presenting cells also express enhanced levels of the coinhibitory molecule programmed cell death ligand 1 (PD-L1), the ligand for PD-1, which is further upregulated upon subsequent stimulation with the CD4+ T helper cell-derived factor CD40L. Interestingly, blocking the PD-1 signaling pathway during MDC1 induction of HIV-1-specific CTL responses inhibited the priming, activation, and differentiation of naive CD8+ T cells into effector T cells expressing high levels of T-box transcription factor (T-bethi) and eomesodermin (Eomes+). In contrast, PD-1 blockade enhanced the overall magnitude of memory HIV-specific CTL responses and reversed the exhausted memory phenotype from a T-betlow/Eomes+ to a T-bethi/Eomes+ phenotype. These results indicate that the PD-L1/PD-1 signaling pathway has a previously unappreciated dual role in the induction and regulation of HIV-1-specific CTL immunity, which is greatly determined by the context and differentiation stage of the responsive CD8+ T cells.IMPORTANCE Targeting the PD-1/PD-L1 immune checkpoint axis with signaling inhibitors has proven to be a powerful immunotherapeutic strategy to enhance the functional quality and survival of existing antigen-specific effector T cells. However, our study demonstrates that the context and timing of PD-1 signaling in T cells greatly impact the outcome of the effector response. In particular, we show that PD-1 activation plays a positive role during the DC-mediated initiation stage of the primary T cell response, while it serves as an inhibitory mechanism during the effector phase of the response. Therefore, caution should be taken in the design of therapies that include targeting of the PD-1/PD-L1 signaling pathway in order to avoid potential negative impacts on the induction of de novo T cell responses.
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Antígeno B7-H1/metabolismo , Células Dendríticas/imunologia , HIV-1/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Linfócitos T Citotóxicos/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Adulto , Ligante de CD40/metabolismo , Infecções por HIV/imunologia , Humanos , Evasão da Resposta Imune/imunologia , Memória Imunológica/imunologia , Subunidade p35 da Interleucina-12/imunologia , Ativação Linfocitária/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Transdução de Sinais/imunologiaRESUMO
OBJECTIVE: Ongoing HIV replication while receiving combination antiretroviral therapy (cART) may reduce survival. Viremia copy-years (VCY) has shown improved mortality risk prediction over single time-point viral load measures. However, the timing of a patient's viral load history most associated with later mortality has not been studied. Here we determined the optimal duration and temporality of viral load history for predicting mortality. DESIGN: Survival analysis among HIV-positive men who initiated cART in the Multicenter AIDS Cohort Study (1995-2015). METHODS: VCY measures were derived from area-under-the-viral load-curve. The overall VCY based upon the complete post-cART viral load history was compared with 20 VCYs derived from viral loads assessed during different shorter time periods (the most recent 1-10 years and initial 1-10 years following cART initiation) for associations with mortality. RESULTS: Each 10-fold increase in VCYs based on the most recent 3-8 years was significantly associated with 23-26% decrease in survival times, a magnitude of effect greater than that of the most recent viral load (16%). These associations were independent of CD4 cell count and single time-point viral loads. In addition, the degree of pre-cART immunodeficiency did not affect the mortality prognostic value of VCY based on viral loads in the most recent 3 years. Conversely, the overall VCY and VCYs based on viral loads immediately following cART initiation were not independent predictors of mortality. CONCLUSION: Among cART-treated men, VCY based upon viral loads in the recent 3 years (six viral loads) has a mortality prognostic value greater than that of the overall VCY and single time-point viral loads, making the former a more feasible measure for use.
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Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , Infecções por HIV/mortalidade , Carga Viral , Viremia/tratamento farmacológico , Viremia/mortalidade , Adulto , Infecções por HIV/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Análise de Sobrevida , Fatores de Tempo , Viremia/virologiaRESUMO
BACKGROUND: Broadly neutralizing monoclonal antibodies (bnMAbs) may promote clearance of HIV-1-expressing cells through antibody-dependent cell-mediated cytotoxicity. We evaluated the effect of the CD4-binding site bnMAb, VRC01, on measures of HIV-1 persistence in chronically infected individuals. METHODS: A5342 was a phase 1, randomized, double-blind, placebo-controlled, parallel-arm study. Participants on effective antiretroviral therapy (ART) were randomized to receive 2 infusions of VRC01 (40 mg/kg) at entry and week 3, and 2 infusions of placebo (saline) at weeks 6 and 9; or 2 infusions of placebo at entry and week 3, and 2 infusions of VRC01 at weeks 6 and 9. RESULTS: Infusion of VRC01 was safe and well tolerated. The median fold-change in the cell-associated HIV-1 RNA/DNA ratio from baseline to week 6 was 1.12 and 0.83 for the VRC01 and placebo arms, respectively, with no significant difference between arms (P = .16). There were no significant differences in the proportions with residual plasma viremia ≥1 copies/mL or in phorbol 12-myristate 13-acetate/ionomycin-induced virus production from CD4+ T cells between arms (both P > .05). CONCLUSIONS: In individuals with chronic HIV-1 infection on ART, VRC01 infusions were safe and well tolerated but did not affect plasma viremia, cellular HIV-1 RNA/DNA levels, or stimulated virus production from CD4+ T cells. CLINICALTRIALSGOV IDENTIFIER: NCT02411539.