Mechanisms of mucosal immunity at the female reproductive tract involved in defense against HIV infection

Human immunodeficiency virus-1 remains a major global health threat. Since the virus is often transmitted through sexual intercourse and women account for the majority of new infections within the most endemic regions, research on mucosal immunity at the female reproductive tract (FRT) is of paramount importance. At the FRT, there are intrinsic barriers to HIV-1 infection, such as epithelial cells and the microbiome, and immune cells of both the innate and adaptive arms are prepared to respond in case the virus overcomes the first line of defense. In this review, we discuss recent findings on FRT mucosal mechanisms of HIV-1 defense and highlight research gaps. While defense from HIV-1 infection at the FRT has been understudied, current and future research is essential to develop new therapeutics and vaccines that can protect this unique mucosal site from HIV-1.

Utilization of post-exposure prophylaxis potentially contributed to the changes of risk behaviors among men who have sex with men in China

Background

The HIV infection status among men who have sex with men (MSM) in China is a cause for concern. Post-exposure prophylaxis (PEP) serves as a highly effective biomedical preventive measure against HIV infection. Substantial evidence has established an association between PEP utilization and risk behaviors among MSM, but whether the utilization of PEP has an impact on risk behaviors remains unknown. This study sought to elucidate the impact of PEP usage on risk behaviors among MSM and provide recommendations for developing targeted HIV prevention programs.

Methods

A cohort study was conducted in Qingdao, China, from April 2021 to January 2022. Participants were enlisted by volunteers from community-based organizations through a snowball sampling method. Face-to-face interviews were conducted to collect sociodemographic and behavioral information of participants. The study encompassed a retrospective investigation, baseline survey, and follow-up survey, representing periods before, during, and after PEP usage, respectively. Generalized estimating equations, fitting a Poisson regression model, were applied to scrutinize changes in risk behaviors of MSM during and after PEP usage, in comparison to before PEP usage.

Results

A total of 341 MSM were recruited in the cohort study, with 179 individuals completing the follow-up survey. In comparison to before PEP usage, there was a significant increase in the proportion of Rush Popper usage (17.6% vs. 23.8% vs. 29.6%) and commercial sexual partners (10.9% vs. 17.6% vs. 21.8%) among MSM during and after PEP usage. Before PEP usage, 88.7% of MSM reported having ≥3 temporary sexual partners in the last 6 months. This proportion exhibited no significant change during PEP usage (91.8%), but it significantly increased to 97.8% after PEP usage (P < 0.05). Notably, there was a significant decrease in group sex during and after PEP usage compared to before PEP usage (30.8% vs. 21.4% vs. 21.2%).

Conclusion

The utilization of PEP may impact risk behaviors among MSM, potentially leading to increased Rush Popper usage, temporary sexual partners, and commercial sexual partners after PEP usage, accompanied by a decrease in group sex. Further research is imperative to elucidate the impact of PEP utilization on MSM and develop targeted HIV prevention programs.

Infectious RNA: Human Immunodeficiency Virus (HIV) Biology, Therapeutic Intervention, and the Quest for a Vaccine

Different mechanisms mediate the toxicity of RNA. Genomic retroviral mRNA hijacks infected host cell factors to enable virus replication. The viral genomic RNA of the human immunodeficiency virus (HIV) encompasses nine genes encoding in less than 10 kb all proteins needed for replication in susceptible host cells. To do so, the genomic RNA undergoes complex alternative splicing to facilitate the synthesis of the structural, accessory, and regulatory proteins. However, HIV strongly relies on the host cell machinery recruiting cellular factors to complete its replication cycle. Antiretroviral therapy (ART) targets different steps in the cycle, preventing disease progression to the acquired immunodeficiency syndrome (AIDS). The comprehension of the host immune system interaction with the virus has fostered the development of a variety of vaccine platforms. Despite encouraging provisional results in vaccine trials, no effective vaccine has been developed, yet. However, novel promising vaccine platforms are currently under investigation.

Post-exposure prophylaxis completion and condom use in the context of potential sexual exposure to HIV

OBJECTIVES

Post-exposure prophylaxis (PEP) care remains a challenge for individuals with potential sexual exposure to HIV in terms of PEP completion and ongoing risk behaviours.

METHODS

A retrospective analysis was carried out on data from the French Dat'AIDS prevention cohort (NCT03795376) for individuals evaluated for PEP between 2004 and 2017. A multivariable analysis was performed of predictors of both PEP completion and condom use [odds ratios (ORs)] and their associated probabilities (P, with P > 95% being clinically relevant).

RESULTS

Overall, 29 060 sexual exposures to HIV were evaluated for PEP [36% in men who have sex with men (MSM) and 64% in heterosexuals]. Overall, 12 different PEP regimens were offered in 19 240 cases (46%). Tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC) was the preferred backbone (n = 14 304; 74%). We observed a shift from boosted protease inhibitor-based regimens to nonnucleoside reverse transcriptase inhibitor- or integrase inhibitor-based regimens in recent years. Overall, 20% of PEP prescriptions were prematurely discontinued. Older age, MSM, intercourse with a sex worker, rape and intercourse with a known HIV-infected source patient were factors associated with increased rates of PEP completion (OR > 1; P > 98%). None of the 12 PEP regimens was associated with premature discontinuation. We also found 12 774 cases of unprotected sexual intercourse (48%). Condom use decreased (OR < 1; P > 99%) with the year of exposure, and was lower in MSM and rape victims. Condom use increased (OR > 1, P > 99%) with age, and was higher in those who had intercourse with a sex worker or with a female partner and in those with knowledge of the partner's HIV status.

CONCLUSIONS

We provide new insights into how rates of condom use and PEP completion might be improved in those receiving PEP by targeting certain groups of individuals for interventions. In particular, youth and MSM at risk should be linked in a prevention-to-care continuum.

Current Peptide and Protein Candidates Challenging HIV Therapy beyond the Vaccine Era

Human immunodeficiency virus (HIV) is a causative agent of acquired immune deficiency syndrome (AIDS). Highly active antiretroviral therapy (HAART) can slow down the replication of HIV-1, leading to an improvement in the survival of HIV-1-infected patients. However, drug toxicities and poor drug administration has led to the emergence of a drug-resistant strain. HIV-1 immunotherapy has been continuously developed, but antibody therapy and HIV vaccines take time to improve its efficiency and have limitations. HIV-1-specific chimeric antigen receptor (CAR)-based immunotherapy founded on neutralizing antibodies is now being developed. In HIV-1 therapy, anti-HIV chimeric antigen receptors showed promising data in the suppression of HIV-1 replication; however, autologous transfusion is still a problem. This has led to the development of effective peptides and proteins for an alternative HIV-1 treatment. In this paper, we provide a comprehensive review of potent anti-HIV-1 peptides and proteins that reveal promising therapeutic activities. The inhibitory mechanisms of each therapeutic molecule in the different stages of the HIV-1 life cycle will be discussed herein.

Prevention of transmission of HIV, hepatitis B virus, hepatitis C virus, and tuberculosis in prisoners

The prevalence of HIV, hepatitis B virus, hepatitis C virus, and tuberculosis are higher in prisons than in the general population in most countries worldwide. Prisons have emerged as a risk environment for these infections to be further concentrated, amplified, and then transmitted to the community after prisoners are released. In the absence of alternatives to incarceration, prisons and detention facilities could be leveraged to promote primary and secondary prevention strategies for these infections to improve prisoners health and reduce risk throughout incarceration and on release. Effective treatment of opioid use disorders with opioid agonist therapies (eg, methadone and buprenorphine) prevents blood-borne infections via reductions in injection in prison and after release. However, large gaps exist in the implementation of these strategies across all regions. Collaboration between the criminal justice and public health systems will be required for successful implementation of these strategies.

Predictors of Standard Follow-Up Completion after Sexual Exposure to HIV: Five-Year Retrospective Analysis in a French HIV-Infection Care Center

Objectives

The care of exposed individuals to HIV remains a challenge regarding follow-up completion and HIV-testing of the partner. Identifying patients with risk of not fulfilling HIV-testing follow-up completion (FC), among patients demanding non-occupational post-exposure prophylaxis (nPEP), may improve clinical practice.

Methods

A retrospective chart review was conducted in a single French HIV-infection care center. FC predictors were assessed in a multivariate logistic regression model (Likelihood ratios test).

Results

Between 2009 and 2013, 646 sexual exposures to HIV were evaluated for nPEP, of which 507 effectively received nPEP (78%). FC rate was 30% (194/646). In the multivariate analysis, FC rates rose with age of exposed individuals (OR, 1.04 [0.25–4.28]; p<0.001) and decreased with the year of sexual exposure (OR, 0.74 [0.65–0.85]; p<0.001). FC was associated with sexual encounter with a sex worker (OR, 4.07 [0.98–16.82]; p<0.001) and nPEP use (OR, 2.69 [2.37–3.06]; p<0.001). nPEP early discontinuation was associated with decreased FC rates (OR, 0.18 [0.08–0.39]; p<0.001). No documented nPEP failure was identified. However, five Men who have Sex with Men (MSM) nPEP recipients for unprotected anal receptive intercourse subsequently seroconverted to HIV more than 6 months after nPEP. Seroconversion to HIV was associated with the lack of FC (p = 0.04) and multiple presentations for nPEP over the study period (p = 0.002).

Conclusions

We identified significant predictors of not fulfilling sequential HIV-testing. They appear to be linked with a self-perceived HIV risk, especially in young adults recently exposed. Enhanced counseling in targeted individuals with high risk behaviors and using smartphone and internet-based strategies may be interesting retention in care options.

Trends in condom use and risk behaviours after sexual exposure to HIV: a seven-year observational study

OBJECTIVE

We aimed to determine the trends in numbers and percentages of sexually exposed persons to HIV (SE) consulting an ED for post-exposure prophylaxis (PEP), as well as predictors of condom use.

STUDY DESIGN

We conducted a prospective-observational study.

METHODS

We included all SE attendances in our Emergency Department (ED) during a seven-year study-period (2006-2012). Trends were analyzed using time-series analysis. Logistic Regression was used to define indicators of condom use.

RESULTS

We enrolled 1851 SE: 45.7% reported intercourse without condom-use and 12.2% with an HIV-infected partner. Significant (p<0.01) rising trends were observed in the overall number of SE visits (+75%), notably among men having sex with men (MSM) (+126%). There were rising trends in the number and percentage of those reporting intercourse without condom-use in the entire population +91% (p<0.001) and +1% (p>0.05), in MSM +228% (p<0.001) and +49% (p<0.001), in Heterosexuals +68% (p<0.001) and +10% (p = 0.08). Among MSM, significant rising trends were found in those reporting high-risk behaviours: anal receptive (+450% and +76%) and anal insertive (+l33% and +70%) intercourses. In a multivariate logistic regression analysis, heterosexuals, vaginal intercourse, visit during the night-shift and short time delay between SE and ED visit, were significantly associated with condom-use.

CONCLUSION

We report an increasing trend in the number of SE, mainly among MSM, and rising trends in high-risk behaviours and unprotected sexual intercourses among MSM. Our results indicate that SE should be considered as a high-risk population for HIV and sexually transmitted diseases.

How acceptable are antiretrovirals for the prevention of sexually transmitted HIV?: A review of research on the acceptability of oral pre-exposure prophylaxis and treatment as prevention

Recent research has demonstrated how antiretrovirals (ARVs) could be effective in the prevention of sexually transmitted HIV. We review research on the acceptability of oral pre-exposure prophylaxis (PrEP) and treatment as prevention (TasP) for HIV prevention amongst potential users. We consider with whom, where and in what context this research has been conducted, how acceptability has been approached, and what research gaps remain. Findings from 33 studies show a lack of TasP research, PrEP studies which have focused largely on men who have sex with men (MSM) in a US context, and varied measures of acceptability. In order to identify when, where and for whom PrEP and TasP would be most appropriate and effective, research is needed in five areas: acceptability of TasP to people living with HIV; motivation for PrEP use and adherence; current perceptions and management of risk; the impact of broader social and structural factors; and consistent definition and operationalisation of acceptability which moves beyond adherence.

Can treatment-based HIV prevention curb the epidemic among gay and other men who have sex with men? A narrative synthesis of increasing evidence for moderating and countervailing effects

As HIV epidemics among gay and other men who have sex with men (GMSM) persist worldwide, the importance of novel prevention approaches is recognised. Evidence that antiretroviral therapy (ART) can decrease the likelihood of infection is informing emerging HIV prevention approaches, encompassing early initiation of treatment as prevention by people living with HIV and use of antiretroviral drugs as pre-exposure prophylaxis for people presumed to be uninfected. Despite widespread excitement, robust evidence of the beneficial effects of ART-based HIV prevention for GMSM remains limited. Also, theoretical models project widely varying effects of ART-based prevention on the future course of HIV epidemics among GMSM, drawing attention to the possible moderating role of differences in the achievements of local HIV responses and the critical importance of sustained protective sexual practices into the future. Ecological analyses and simulations of ongoing epidemics in major gay communities illustrate that the preventive effects of ART in many settings are being offset by increased sexual risk-taking, as reflected in stable or increasing HIV infection rates. Also, the effects of scaling up HIV testing and treatment among GMSM in settings that are often considered prime examples of the success of ART-based prevention may be levelling as ‘scope for improvement’ diminishes. ART-based approaches further extend the HIV prevention toolkit and substantially increase people’s options to protect themselves and others. The future impact of ART-based prevention on HIV epidemics among GMSM ultimately depends on whether heralded responses offset, attenuate or compound the ongoing social and behavioural changes that drive increased sexual risk.

Pre-exposure prophylaxis (PrEP) for HIV infection: results of a survey of HIV healthcare providers evaluating their knowledge, attitudes, and prescribing practices

Antiretroviral medications can be taken by HIV-negative persons to prevent HIV infection, also known as pre-exposure prophylaxis (PrEP). PrEP was first shown to be effective during the iPrEX study. We conducted a survey involving HIV healthcare providers to document their attitudes and prescribing practices about PrEP in response to this study. An online survey was completed by 189 members and credentialees of the American Academy of HIV Medicine between April 2011 and September 2011. Ninety percent of respondents were familiar with the results of the iPrEx study, and most (78%) were familiar with CDC's interim guidance regarding the use of PrEP in MSM. Only 19% of respondents had prescribed PrEP. The majority of PrEP prescribers were compliant with CDC interim guidance; however, only 61% screened for hepatitis B. Of PrEP prescribers, 78% prescribed to MSM, 31% to MSW, and 28% to WSM. Greatest concerns about prescribing PrEP included development of antiretroviral resistance (32%), potential increase in high-risk behavior, (22%) and poor medication adherence (21%). Fifty-eight percent stated that HIV serodiscordance within a relationship most influenced their decision to prescribe PrEP to the HIV-seronegative partner. This study demonstrates that, despite awareness of the efficacy of PrEP, its use is limited. Survey participants used PrEP most commonly in MSM; however, a significant percentage also prescribed PrEP to women. The best candidate for PrEP is felt to be individuals in an HIV-serodiscordant relationship. Limitations to our study included a low response rate, changes in the evidence base, and the novelty of PrEP.

Can combination prevention strategies reduce HIV transmission in generalized epidemic settings in Africa? The HPTN 071 (PopART) study plan in South Africa and Zambia

The HIV Prevention Trials Network (HPTN) is conducting the HPTN 071 (PopART) study in 21 communities in Zambia and South Africa with support from a consortium of funders. HPTN 071 (PopART) is a community-randomized trial of a combination prevention strategy to reduce HIV incidence in the context of the generalized epidemic of southern Africa. The full PopART intervention strategy is anchored in home-based HIV testing and facilitated linkage of HIV-infected persons to care through community health workers and universal antiretroviral therapy for seropositive persons regardless of CD4+ cell count or HIV viral load. To further reduce the risk of HIV acquisition among uninfected individuals, the study aims to expand voluntary medical male circumcision, diagnosis and treatment of sexually transmitted infections, behavioral counseling, and condom distribution. The full PopART intervention strategy also incorporates promotion of other interventions designed to reduce HIV and tuberculosis transmission, including optimization of the prevention of mother-to-child HIV transmission and enhanced individual and public health tuberculosis services. Success for the PopART strategy depends on the ability to increase coverage for the study interventions whose uptake is a necessary antecedent to a prevention effect. Processes will be measured to assess the degree of penetration of the interventions into the communities. A randomly sampled population cohort from each community will be used to measure the impact of the PopART strategy on HIV incidence over 3 years. We describe the strategy being tested and progress to date in the HPTN 071 (PopART) study.

Falling short of universal access to reproductive health: unintended pregnancy and contraceptive use among Mexican women with HIV

A favourable context for women with HIV to prevent unintended pregnancy is a cornerstone of reproductive rights and will contribute to achieving universal access to reproductive health, a Millennium Development Goal target. This analysis explores the reproductive trajectories of Mexican women with HIV post-diagnosis and their access to reproductive counselling and use of contraceptives. In-depth interviews and short surveys were conducted with women of reproductive age living with HIV. Results indicate that sexual and reproductive health counselling in HIV care focuses on the male condom and does not routinely address reproductive desires or provide information about or access to other contraceptive methods. Unintended pregnancies result from inconsistent condom use and condom breakage. Women experienced discriminatory denial of and pressure to accept particular contraceptive methods because of their HIV status. Mexican women with HIV are not enjoying their constitutionally guaranteed right to freely choose the number and spacing of their children. Mexico's commitment to reproductive rights and the Popular Health Insurance offer policy and financial frameworks for providing family planning services in public HIV clinics. To ensure respectful implementation, rights-based training for HIV healthcare providers and careful monitoring and evaluation will be needed.