HIV Prevention and Care Among Black Cisgender Sexual Minority Men and Transgender Women: Protocol for an HIV Status–Neutral Cohort Study Using an Observational-Implementation Hybrid Approach

Background: Black cisgender gay, bisexual, and other sexual minority men (SMM) and transgender women (TW) continue to be heavily affected by HIV. Further research is needed to better understand HIV prevention and care outcomes in this population. In particular, there is a need for research examining the impact of substance use and sleep health on HIV prevention and treatment outcomes among Black SMM and TW. Objective: This paper outlines the study methods being used in the recently launched follow-up study to the Neighborhoods and Networks (N2) study, which we refer to as N2 Part 2 (N2P2). N2P2 aims to address this gap in the literature, build off the findings of the original N2 study, and identify socioenvironmental determinants of health, including whether neighborhood and network factors mediate and moderate these relationships. Methods: Building on the N2 cohort study in Chicago from 2018 to 2022, N2P2 used a prospective longitudinal cohort design and an observational-implementation hybrid approach. With sustained high levels of community engagement, we aim to recruit a new sample of 600 Black SMM and TW participants residing in the Chicago metropolitan statistical area. Participants are asked to participate in 3 study visits across an 18-month study period (1 visit every 9 months). Four different forms of data are collected per wave: (1) an in-person survey, (2) biological specimen collection, (3) a daily remote ecological momentary assessment for 14 days after each study visit, and (4) data from electronic health records. These forms of data collection continue to assess neighborhood and network factors and specifically explore substance use, sleep, immune function, obesity, and the implementation of potential interventions that address relevant constructs (eg, alcohol use and pre-exposure prophylaxis adherence). Results: The N2P2 study was funded in August 2021 by the National Institute of Drug Abuse (R01DA054553 and R21DA053156) and National Heart, Lung, and Blood Institute (R01HL160325). This study was launched in November 2022. Recruitment and enrollment for the first wave of data collection are currently ongoing. Conclusions: The N2P2 study is applying innovative methods to comprehensively explore the impacts of substance use and sleep health on HIV-related outcomes among an HIV status-neutral cohort of Black SMM and TW in Chicago. This study is applying an observational-implementation hybrid design to help us achieve findings that support rapid translation, a critical priority among populations such as Black SMM and TW that experience long-standing inequities with regard to HIV and other health-related outcomes. N2P2 will directly build off the findings that have resulted from the original N2 study among Black SMM and TW in Chicago. These findings provide a better understanding of multilevel (eg, individual, network, and neighborhood) factors that contribute to HIV-related outcomes and viral suppression among Black SMM and TW. International registered report identifier (irrid): DERR1-10.2196/48548.</p

Zonulin as a biomarker and potential therapeutic target in multisystem inflammatory syndrome in children

Multisystem inflammatory syndrome in children (MIS-C) occurs during or recently following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and is characterized by persistent fever, inflammation, and severe illness requiring hospitalization. The majority of patients with MIS-C also present with gastrointestinal (GI) symptoms, including abdominal pain, vomiting, and diarrhea. In this issue of the JCI, Yonker, Gilboa, and colleagues identified zonulin as a biomarker of GI permeability in children with MIS-C and present the results of an intriguing proof-of-concept study indicating that zonulin may represent a potential therapeutic target for MIS-C treatment and prevention. Their findings suggest that intestinal mucosal dysfunction and epithelial barrier breakdown may represent a biological mechanism underlying the development of MIS-C in SARS-CoV-2–infected children

Probiotic therapy during vaccination alters antibody response to SHIV infection but not to commensals

The induction of robust circulating antibody titers is a key goal of HIV-1 vaccination. Probiotic supplementation is an established strategy to enhance microbiota and boost antibody responses to vaccines. A recent study tested whether oral probiotics could enhance vaccine-specific mucosal immunity by testing vaccination with and without supplementation in a Rhesus macaque Simian-Human Immunodeficiency Virus challenge model. Although supplementation was not associated with protection, the effects of probiotics on immunity after infection were not examined. To address this question, we measured antibody titers to HIV Env and commensal bacteria in plasma from the vaccination/supplementation time points as well as after SHIV acquisition. We found that a trend toward lower HIV Env-specific titers in the animals given probiotics plus vaccine became greater after SHIV infection. Significantly lower IgA titers were observed in animals vaccinated and supplemented compared to vaccine alone due to a delay in antibody kinetics at week 2 post infection. We observed no difference, however, in titers to commensal bacteria during probiotic supplementation or after SHIV infection. These results suggest that probiotic supplementation may be a strategy for reducing IgA-specific HIV antibodies in the plasma, a correlate associated with increased HIV infection in the RV144 clinical trial

Problematic Cannabis Use Is Associated with Reduced Rectal Microbial Species Richness and Diversity Among a Pilot Sample of Young Sexual and Gender Minorities

Compared to young heterosexual men, young sexual and gender minorities (YSGM) have elevated systemic inflammation and unique intestinal microbial profiles, influenced by HIV infection and substance use. However, links between cannabis use and microbial dysbiosis in this population have not been well described. In this pilot study, we aimed to characterize the complex interrelationships between cannabis use and microbial community structure in YSGM in relationship to HIV status. Cannabis use was assessed by self-administered Cannabis Use Disorder Identification Test (CUDIT) questionnaires and rectal microbial community alpha-diversity metrics were assessed via 16S ribosomal ribonucleic acid (rRNA) sequencing in a subset of YSGM (  = 42) in the RADAR cohort (aged 16-29) in Chicago. Multivariable regression models were used to assess the relationship between cannabis use and microbiome alpha-diversity metrics, adjusting for HIV status and other risk characteristics, including inflammation, which was evaluated by plasma levels of C-reactive protein (CRP). Problematic cannabis use, but not general use, was significantly inversely associated with microbial community richness (Adj. Beta = -8.13; 95% confidence interval [CI]: -15.68 to -0.59) and Shannon diversity (Adj. Beta = -0.04; 95% CI: -0.07 to 0.009). No significant association was observed between CUDIT score and community evenness, nor was any significant moderation observed by HIV status. We observed that problematic cannabis use was associated with reduced microbial community richness and Shannon diversity, adjusting for within population differences in inflammation and HIV status. Future research should aim to assess how cannabis use contributes to microbiome-related health factors among YSGM and if decreasing cannabis use can restore gut microbial community structure

Objective Identification of Cannabis Use Levels in Clinical Populations Is Critical for Detecting Pharmacological Outcomes

Introduction: Cannabis is widely used for recreational and medical purposes, but its therapeutic efficacy remains unresolved for many applications as data from retrospective studies show dramatic discrepancy. We hypothesized that false self-reporting of cannabis use and lack of differentiation of heavy users from light or occasional users contribute to the conflicting outcomes. Objective: The goal of this study was to develop an objective biomarker of cannabis use and test how application of such biomarker impacts clinical study outcomes and dose-response measures. Methods and Analysis: Population pharmacokinetic (PK) models of (-)-trans-Δ9-tetrahydrocannabinol (THC) and its metabolites 11-hydroxy-Δ9-tetrahydrocannabinol (11-OH-THC) and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (11-COOH-THC) were developed based on published studies reporting cannabinoid disposition in individual subjects following intravenous administration or smoking of cannabis. Plasma 11-COOH-THC concentration distributions in different cannabis user groups smoking cannabis were generated via Monte Carlo simulations, and plasma concentration cutoff values of 11-COOH-THC were developed to differentiate light and heavy daily cannabis users in clinical studies. The developed cutoff value was then applied to a retrospective study that assessed the impact of cannabis use on T cell activation in subjects with HIV who self-reported as either nonuser or daily user of cannabis. Results: The developed population PK models established plasma 11-COOH-THC concentration of 73.1 μg/L as a cutoff value to identify heavy daily users, with a positive predictive value of 80% in a mixed population of equal proportions of once daily and three times a day users. The stratification allowed detection of changes in T cell activation in heavy users which was not detected based on self-reporting or detectability of plasma cannabinoids. A proof-of-concept power analysis demonstrated that implementation of such cutoff value greatly increases study power and sensitivity to detect pharmacological effects of cannabis use. Conclusions: This study shows that the use of plasma 11-COOH-THC concentration cutoff value as an objective measure to classify cannabis use in target populations is critical for study sensitivity and specificity and provides much needed clarity for addressing dose-response relationships and therapeutic effects of cannabis

Brief Report: Hazardous Cannabis Use and Monocyte Activation Among Methamphetamine Users With Treated HIV Infection

The use of stimulants, such as methamphetamine, has been associated with greater immune activation in treated HIV infection. However, relatively little is known about whether concomitant cannabis use is associated with lower immune activation among HIV-positive stimulant users. HIV-positive, sexual minority men with biologically confirmed, recent methamphetamine use were enrolled in San Francisco, CA. In total, 78 methamphetamine-using sexual minority men with an undetectable HIV viral load (<40 copies/mL) completed self-report measures of cannabis use and substance use disorder severity. Plasma biomarkers of monocyte activation (ie, sCD14 and sCD163) and intestinal barrier integrity (iFABP) were measured. The associations of hazardous cannabis use with these measurements were examined after adjusting for substance use disorder severity, age, antiretroviral therapy regimen, CD4 T-cell count, and interleukin-6. Hazardous cannabis users had the highest mean sCD14 levels (2181 ng/mL) compared with nonhazardous users (1991 ng/mL) and nonusers (1859 ng/mL; P = 0.05). In adjusted analyses, greater cannabis use severity was associated with higher sCD14 compared with nonusers (unstandardized beta = 133.6 ng/mL, P = 0.03). Cannabis use severity was not significantly associated with sCD163 or iFABP. Hazardous cannabis use is independently associated with elevations in a clinically relevant marker of immune activation in methamphetamine users with treated HIV

Microbial exposure alters HIV-1-induced mucosal CD4+ T cell death pathways Ex vivo

BACKGROUND: Early HIV-1 infection causes massive CD4+ T cell death in the gut and translocation of bacteria into the circulation. However, the programmed cell death (PCD) pathways used by HIV-1 to kill CD4+ T cells in the gut, and the impact of microbial exposure on T cell loss, remain unclear. Understanding mucosal HIV-1 triggered PCD could be advanced by an ex vivo system involving lamina propria mononuclear cells (LPMCs). We therefore modeled the interactions of gut LPMCs, CCR5-tropic HIV-1 and a commensal gut bacterial species, Escherichia coli. In this Lamina Propria Aggregate Culture (LPAC) model, LPMCs were infected with HIV-1(BaL) by spinoculation and cultured in the presence or absence of heat killed E.coli. CD4+ T cell numbers derived from flow cytometry and viable cell counts were reported relative to mock infection. Viable cells were identified by viability dye exclusion (AqVi), and intracellular HIV-1 Gag p24 protein was used to identify infected cells. Annexin V and AqVi were used to identify apoptotic versus necrotic cells. Caspase-1 and Caspase-3 activities were blocked using specific inhibitors YVAD and DEVD, respectively. RESULTS: CD4+ T cell depletion following HIV-1 infection was reproducibly observed by 6 days post infection (dpi). Depletion at 6 dpi strongly correlated with infection frequency at 4 dpi, was significantly blocked by Efavirenz treatment, and was primarily driven by p24-negative cells that were predominantly necrotic. HIV-1 infection significantly induced CD4+ T-cell intrinsic Caspase-1 activity, whereas Caspase-1 inhibition, but not Caspase-3 inhibition, significantly blocked CD4+ T cell depletion. Exposure to E.coli enhanced HIV-1 infection and CD4+ T depletion, and significantly increased the number of apoptotic p24+ cells. Notably, CD4+ T cell depletion in the presence of E.coli was partially blocked by Caspase-3, but not by Caspase-1 inhibition. CONCLUSIONS: In the LPAC model, HIV-1 induced Caspase-1 mediated pyroptosis in bystander CD4+ T cells, but microbial exposure shifted the PCD mechanism toward apoptosis of productively infected T cells. These results suggest that mucosal CD4+ T cell death pathways may be altered in HIV-infected individuals after gut barrier function is compromised, with potential consequences for mucosal inflammation, viral dissemination and systemic immune activation

1289. Douching and Rectal Inflammation in Sexual Minority Men: Implications for HIV Acquisition

Abstract Background Rectal douching is the practice of rinsing the anus and rectum prior to, or after, anal sex. Among gay, bisexual, and other men who have sex with men (sexual minority men), rectal douching is likely to enhance HIV acquisition by amplifying inflammation of the rectal mucosa. This study evaluated the association of rectal douching with rectal inflammation among sexual minority men at risk for HIV infection. Methods HIV uninfected sexual minority men who reported receptive anal intercourse in the past 3 months (N = 197) were recruited from four STI clinics in South Florida, the leading region for new HIV infections among sexual minority men in the United States. A brief survey assessed rectal douching practices and sexual behaviors in the previous 3 months. Rectal inflammation was assessed by measuring 13 human rectal inflammatory cytokines/chemokines in rectal swabs using the LEGENDplex Human Inflammation Panel in a sample of 38 participants who reported douching and condomless receptive anal intercourse (CRAI). Results Average age was 35.8 years (SD=15.4). The sample was multi-ethnic: 42% Caucasian, 38% Hispanic/Latino, 13% Black/African American, and 7% other ethnic minority. Approximately two-thirds of participants (65%) reported any rectal douching in the past 3 months and the median number times participants douched was five. Participants who douched had more CRAI partners (Cohen’s d = 0.4587; P < 0.01), and more CRAI partners to ejaculation (Cohen’s d = 0.4813; P < 0.01) compared with participants who did not douche. Participants who reported douching five or more times in the past 3 months displayed significantly higher levels of IL-8 (Cohen’s d = 0.79; P = 0.02) than those who douched less than five times. Conclusion Among sexual minority men who engage in CRAI, more frequent douching is associated with higher levels of rectal inflammation. Assessment of rectal douching should be included when evaluating HIV prevention interventions among sexual minority men, as those who douche are more likely to engage in CRAI and are at higher risk for acquisition of HIV and other sexually transmitted infection. Further mechanistic studies are needed to assess the role of rectal douching in promoting rectal inflammation. Disclosures All authors: No reported disclosures