ABSTRACT
The genetic background of the high prevalence red blood cell antigen AnWj has remained unresolved since its identification in 1972, despite reported associations with both CD44 and Smyd1 histone methyltransferase. Development of anti-AnWj, which may be clinically significant, is usually due to transient suppression of antigen expression, but a small number of individuals with persistent, autosomally-recessive inherited AnWj-negative phenotype have been reported. Whole exome sequencing of individuals with the rare inherited AnWj-negative phenotype revealed no shared mutations in CD44H or SMYD1, but instead we discovered homozygosity for the same large exonic deletion in MAL, which was confirmed in additional unrelated AnWj-negative individuals. MAL encodes an integral multi-pass membrane proteolipid, Myelin and Lymphocyte protein (Mal), which has been reported to have essential roles in cell transport and membrane stability. AnWj-positive individuals were shown to express full-length Mal on their red cell membranes, which was not present on the membranes of AnWj-negative individuals, whether of an inherited or suppression background. Furthermore, binding of anti-AnWj was able to inhibit binding of anti-Mal to AnWj-positive red cells, demonstrating the antibodies bind to the same molecule. Over-expression of Mal in an erythroid cell-line resulted in expression of AnWj antigen, regardless of the presence or absence of CD44, demonstrating that Mal is both necessary and sufficient for AnWj expression. Our data resolve the genetic background of the inherited AnWj-negative phenotype, forming the basis of a new blood group system, further reducing the number of remaining unsolved blood group antigens.
ABSTRACT
Black gay, bisexual, and other men who have sex with men (GBM) are disproportionately affected by HIV and STIs. Safe Spaces 4 Sexual Health (SS4SH), a community-informed, status-neutral HIV/STI testing intervention combines online outreach via geo-social networking apps and social media with mobile van testing. During 2018-2019, we recruited 25 participants for interviews about their perceptions of SS4SH compared to clinic-based testing. Participants were aged 21-65 years (mean 35); 22 (88%) identified as Black/African American; 20 (80%) identified as gay; and 10 (40%) were living with HIV. Interviews were transcribed, coded, and analyzed using a modified thematic constant comparative approach. Five themes emerged; two related to perceptions of online outreach materials (participants were drawn to eye-catching and to-the-point messages and desired more diversity and representation in messages), and three related to preference for the mobile van (participants found SS4SH provided more comfort, more privacy/confidentiality, and increased accessibility and efficiency). GBM is increasingly using geo-social networking apps to meet sexual partners, and tailored online outreach has the potential to reach historically underserved populations. SS4SH is a barrier-reducing strategy that may serve as an entry to a status-neutral approach to services and help reduce stigma and normalize accessing HIV services.
ABSTRACT
BACKGROUND: Syphilis epidemics among women and men-who-have-sex-with-men (MSM) may be connected, but these connections are poorly understood. Using egocentric network data from a U.S. urban MSM cohort, we examined socio-demographics, behaviors, and syphilis positivity among MSM with (1) direct (MSM who report sex with women, MSMW); (2) indirect (MSM who only report male partners, some of whom are MSMW, MSMO/W); and (3) no (MSM who only report male partners and whose partners only have sex with men, MSMO/O) connection to women. METHODS: Sexually-active MSM aged 18-45 years were administered behavioral and network interviews (recall period: three months) and syphilis/HIV testing. Syphilis positivity was defined as RPR titer >1:8. Modified Poisson regression was used to test for differences across groups. RESULTS: Among 385 MSM, 14.5% were MSMW and 22.3% were MSMO/W. MSMW and MSMO/W were significantly more likely than MSMO/O to report sex behaviors associated with increased syphilis acquisition/transmission risk, including: > 2 sex partners [MSMW aPR:1.28 (0.98-1.68); MSMO/W aPR:1.35 (1.09-1.69)], concurrent sex partners [MSMW aPR:1.50 (1.17-1.92); MSMO/W aPR:1.39 (1.11-1.74)], and for MSMW only, transactional sex [aPR:2.07 (1.11-3.88)]. Syphilis positivity was 16.4% and was lower among MSMW (9.4%) and MSMO/W (14.1%) than MSMO/O (18.5%), but differences were not significant. CONCLUSIONS: There may be considerable connectivity between MSM and female sex partners that could facilitate syphilis transmission, and behaviors that increase acquisition/transmission risk among MSMW and MSMO/W may be distinct from MSMO/O. Future work should focus on examining the context and temporal patterns of sex partnerships among MSMW and MSMO/W.
ABSTRACT
Pre-exposure prophylaxis (PrEP) is an effective tool in protecting persons from acquiring HIV infection through sex or injection drug use. However, awareness and willingness to use PrEP among Black gay, bisexual, and other men who have sex with men (BMSM) remain suboptimal compared to White MSM (WMSM) in the United States. Our aims were to (1) assess the factors associated with PrEP awareness and willingness to use PrEP among MSM and (2) compare the PrEP perceptions among BMSM versus non-Black MSM. Data were drawn from two cross-sectional behavioral surveys in Baltimore, MD: Behavioral Surveillance Research (BESURE) conducted in 2017, and Safe Spaces 4 Sexual Health (SS4SH), conducted in 2018 and 2019. Descriptive statistics were used to summarize the study population. We used Poisson regression models to identify variables associated with awareness of PrEP and willingness to use PrEP. PrEP perceptions were assessed via 13 items scored on a 5-point Likert scale. Finally, we conducted a post-hoc exploratory bivariate analysis of the relationship between PrEP perception and willingness to use PrEP, stratified by race/ethnicity. A total of 261 MSM participated in this study. Many of the participants were aware of PrEP (75.1%). Factors associated with greater PrEP awareness included having greater than a high school education (aRR 1.22, 95% CI 1.04, 1.43); and earning more than $25,000 annually (aRR 1.24, 95% CI 1.08, 1.42). Participants who had received money in exchange for sex one or more times were less likely to be aware of PrEP (aRR 0.59, 95% CI 0.36, 0.95). More than half of the participants were willing to use PrEP (55.3%). In bivariate and multivariable analyses, demographic or behavioral characteristics were not significantly associated with willingness to use PrEP. Higher agreement with the following statements was associated with lower willingness to use PrEP: "Having to take a pill every day is difficult" (RR 0.89, 95% CI 0.82-0.97) and, "I am concerned about the side effects of PrEP" (RR 0.89, 95% CI 0.82-0.96), and "PrEP is for people who have riskier sex lives than I do" (RR 0.86, 95% CI 0.78-0.95). Conversely, higher willingness to use PrEP was associated with comfortable having sex without a condom (RR 1.11, 95% CI 1.02-1.21), less anxious about sex (RR 1.12, 95% CI 1.02-1.24), and my friends think that I should take PrEP (RR 1.19, 95% CI 1.07-1.32). We found BMSM compared to non-Black MSM had higher mean scores related to taking a daily pill (p = 0.041), concerns about side effects (p = 0.012), concerns about people thinking they had HIV (p = 0.001), concerns about the financial costs of PrEP (p = 0.038) and caution when dealing with healthcare organizations/medical mistrust (p = 0.019). Perceptions with a statistically significant lower score among BMSM versus non-Black MSM included statements such as, comfortable having sex without a condom (p = 0.003) and less anxious about sex (p < 0.001). We conclude HIV prevention strategies, programs, and interventions should be cognizant of PrEP perceptions that facilitate or hinder PrEP uptake in Baltimore City, MD.
ABSTRACT
BACKGROUND: Syphilis incidence is increasing among reproductive-aged women, and previous sexually transmitted infections (STIs) are a risk factor for subsequent STIs. This study aimed to determine syphilis incidence after a chlamydia, gonorrhea, or HIV diagnosis, and identify characteristics associated with higher syphilis incidence rates among reproductive-aged women in 1 mid-Atlantic city. METHODS: A retrospective cohort of 85,113 chlamydia, gonorrhea, and HIV diagnoses occurring between 2009 and 2021 and among women aged 13 to 50 years was constructed using public health surveillance data. Cumulative incidence curves were estimated to examine time to early syphilis (i.e., primary, secondary, or early latent) diagnosis, and multivariable analyses determined incidence rate ratios by age (<25 vs. ≥25 years) and number of prior STI diagnoses (0 vs. ≥1) during the study period, stratified by STI. RESULTS: There were 85,113 reportable STI diagnoses and 646 syphilis diagnoses in the cohort. Approximately 1 of 150 chlamydia, 1 of 100 gonorrhea, and 1 of 50 HIV diagnoses were followed by a syphilis diagnosis within 5 years. Cumulative incidence of syphilis differed significantly by STI diagnosis ( P < 0.001). In multivariable analysis, syphilis incidence rates were higher among women diagnosed with ≥1 (vs. 0) prior STI regardless of STI type ( P < 0.05) and among women ≥25 (vs. <25) years old diagnosed with gonorrhea ( P < 0.05). CONCLUSIONS: There were significant differences in syphilis incidence by prior STI type, number of STIs, and age. Our data support targeted screening for syphilis among women with a history of STIs, parwomen with ≥1 prior STI diagnosis, and older women diagnosed with gonorrhea.