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HIV-1 infection is characterized by generalized deregulation of the immune system, resulting in increased chronic immune activation. However, some individuals called HIV controllers (HICs) present spontaneous control of viral replication and have a more preserved immune system. Among HICs, discordant results have been observed regarding immune activation and the frequency of different T cell subsets, including Treg and Th17 cells. We evaluated T cell immune activation, differentiation and regulatory profiles in two groups of HICs—elite controllers (ECs) and viremic controllers (VCs)—and compared them to those of cART-treated individuals (cART) and HIV-1-negative (HIV-neg) individuals. ECs demonstrated similar levels of activated CD4+ and CD8+ T cells in comparison to HIV-neg, while cART and VCs showed elevated T cell activation. CD4+ T cell subset analyses showed differences only for transitional memory T cell frequency between the EC and HIV-neg groups. However, VC individuals showed higher frequencies of terminally differentiated, naïve, and stem cell memory T cells and lower frequencies of transitional memory and central memory T cells compared to the HIV-neg group. Among CD8+ T cell subsets, ECs presented higher frequencies of stem cell memory T cells, while VCs presented higher frequencies of terminally differentiated T cells compared to the HIV-neg group. HICs showed lower frequencies of total Treg cells compared to the HIV-neg and cART groups. ECs also presented higher frequencies of activated and a lower frequency of resting Treg cells than the HIV-neg and cART groups. Furthermore, we observed a high frequency of Th17 cells in ECs and high Th17/Treg ratios in both HIC groups. Our data showed that ECs had low levels of activated T cells and a high frequency of activated Treg and Th17 cells, which could restrict chronic immune activation and be indicative of a preserved mucosal response in these individuals. [ABSTRACT FROM AUTHOR]

Introduction: Efficacy of daily emtricitabine/tenofovir disoproxil fumarate (FTC/TDF) for PrEP is strongly dependent on the adherence. We examined the concordance between indirect adherence measures and protective drug levels among participants retained through 48 weeks in the PrEP Brasil Study. Methods: PrEP Brasil was a prospective, multicenter, open-label demonstration project evaluating PrEP provision for men who have sex with men (MSM) and transgender women (TGW) at higher risk for HIV infection within the setting of Brazilian Public Health System. Three indirect adherence measures were obtained at week 48: medication possession ratio (MPR), pill count and self-report (30-days recall). Tenofovir diphosphate (TFV-DP) concentration in Dried Blood Spot (DBS) was measured at week 48. Areas under (AUC) the receiver operating characteristics (ROC) curve were used to evaluate the concordance between achieving protective drug levels (TFV-DP≥700fmol/punch) and the indirect adherence measures. Youden's index and distance to corner were used to determine the optimal cutoff points for each indirect adherence measure. We calculated sensitivity, specificity, negative (NPV) and positive (PPV) predictive values for the found cutoff points. Finally, Delong test was used to compare AUCs. Results and discussion: From April, 2014 to July, 2016, 450 participants initiated PrEP, 375(83.3%) were retained through 48 weeks. Of these, 74% (277/375) had TFV-DP ≥700fmol/punch. All adherence measures discriminated between participants with and without protective drug levels (AUC>0.5). High indirect adherence measure was predictive of protective drug levels (PPV>0.8) while low indirect adherence measure was not predictive of lack of protective drug levels (NPV<0.5). No significant differences were found between the adherence methods (p = 0.44). Conclusions: Low-burden measurements such as MPR and self-report can be used to predict PrEP adherence in a public health context in Brazil for MSM and TGW retained through 48 weeks. Clinical Trial Number: . [ABSTRACT FROM AUTHOR]

Background: In addition to protecting against HIV acquisition, antiretroviral preexposure prophylaxis (PrEP) using topical 1% tenofovir gel reduced Herpes simplex virus type 2 (HSV-2) acquisition by 51% among women in the CAPRISA 004 study. We examined the effect of daily oral emtricitabine/tenofovir (FTC/TDF) PrEP on HSV-2 seroincidence and ulcer occurrence among men who have sex with men (MSM) in the iPrEx trial. Methods: HSV-2 serum testing was performed at screening and every six months. Among HSV-2-seronegative individuals, we used Cox regression models to estimate hazard ratios (HRs) of HSV-2 seroincidence associated with randomization to FTC/TDF. We used multiple imputation and Cox regression to estimate HRs for HSV-2 seroincidence accounting for drug exposure. We assessed ulcer occurrence among participants with prevalent or incident HSV-2 infection. Results: Of the 2,499 participants, 1383 (55.3%) tested HSV-2-seronegative at baseline, 892 (35.7%) tested positive, 223 (8.9%) had indeterminate tests, and one test was not done. Of the 1,347 HSV-2-seronegative participants with follow-up, 125 (9.3%) had incident HSV-2 infection (5.9 per 100 person-years). Compared with participants receiving placebo, there was no difference in HSV-2 seroincidence among participants receiving FTC/TDF (HR 1.1, 95% CI: 0.8–1.5; P = 0.64) or among participants receiving FTC/TDF with a concentration of tenofovir diphosphate >16 per million viable cells (HR 1.0, 95% CI: 0.3–3.5; P = 0.95). Among participants with HSV-2 infection, the proportion with ≥1 moderate or severe ulcer adverse event was twice as high in the placebo vs. active arm (5.9% vs. 2.9%, P = 0.02), but there were no differences in the proportions with ≥1 clinical examination during which perianal or groin ulcers were identified. Conclusions: Tenofovir in daily oral FTC/TDF PrEP may reduce the occurrence of ulcers in individuals with HSV-2 infection but does not protect against HSV-2 incidence among MSM. [ABSTRACT FROM AUTHOR]

HIV self-testing (HIVST) is an essential tool within the combined HIV prevention package and has been available in Latin America since 2015. However, HIVST use among key populations remains low. This study describes awareness, willingness, and barriers to HIVST among MSM in Brazil, Mexico, and Peru. A cross-sectional web-based survey was advertised in two geosocial networking apps (Grindr and Hornet) and Facebook in 2018. We included cisgender men ≥18 years old who self-reported HIV-negative status. We used multivariable Poisson regression models to calculate adjusted prevalence ratios (aPR) to assess the factors associated with willingness to use HIVST for each country. A total of 18,916 completed the survey, 59% from Brazil, 30% from Mexico, and 11% from Peru. Overall, 20% of MSM had never tested for HIV. Awareness and willingness to use HIVST were higher in Brazil than in Peru and Mexico (p < .001). Across the countries, the patterns of association of willingness with HIVST barriers were similar. Most participants think post-test counseling is essential and that dealing with a positive result would be difficult (aPR 1.13 to 1.37, range of aPRs across the three countries). Having the knowledge to deal with a positive HIVST resulted in increased willingness to use HIVST (aPR range: 1.11 to 1.22), while a lack of trust in HIVST compared to HIV testing in clinics was inversely associated (aPR range: 0.80 to 0.90). In general, willingness to use HIVST was associated with higher income (aPR range: 1.49 to 1.97), higher education (aPR range: 1.13 to 1.42), and willingness to use PrEP (aPR range: 1.19 to 1.72). Efforts to increase HIVST knowledge and resolve perceived barriers are warranted, especially among MSM with lower income and education from Brazil, Mexico, and Peru. Personalized virtual counseling could be crucial among this population. In addition, those willing to use HIVST are also willing to use PrEP. It indicates that HIVST delivery could be incorporated into PrEP programs within the Brazilian Public Health System and eventually in Mexico and Peru., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Elorreaga et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)