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IntroductionAdherence to HIV prevention methods is a challenge, particularly for young women in Sub-Saharan Africa. End-user research during product development can inform modifiable factors to increase future uptake and adherence.MethodsPreferences for four vaginally inserted placebo HIV prevention methods were assessed among Zimbabwean and South African young women using a crossover clinical design. For each of months 1 to 4, participants were asked to use a pre-coitally inserted film, insert (vaginal tablet) and gel once/week for a month, and a monthly ring in a randomly assigned sequence. Participants subsequently chose one preferred product to use as directed for the final study month. Women ranked the four products from most preferred to least preferred at enrolment and after trying all products.ResultsA total of 200 women aged 18 to 30 (mean 23) were enrolled; 178 (89%) completed follow-up. At baseline, 41% of participants selected the gel as their most preferred product and 61% selected the ring as least preferred. During the crossover period, most (82% to 85%) self-reported using each product at least once a week, although only half the time with sex. Objective biomarker data confirmed adequate use of all products. After trying each product, rankings changed with the film, ring, insert and gel being selected by 29%, 28%, 26% and 16% respectively. Choice varied significantly by country (p

: Introduction: Adherence to HIV prevention methods is a challenge, particularly for young women in Sub?Saharan Africa. End?user research during product development can inform modifiable factors to increase future uptake and adherence. Methods: Preferences for four vaginally inserted placebo HIV prevention methods were assessed among Zimbabwean and South African young women using a crossover clinical design. For each of months 1 to 4, participants were asked to use a pre?coitally inserted film, insert (vaginal tablet) and gel once/week for a month, and a monthly ring in a randomly assigned sequence. Participants subsequently chose one preferred product to use as directed for the final study month. Women ranked the four products from most preferred to least preferred at enrolment and after trying all products. Results: A total of 200 women aged 18 to 30 (mean 23) were enrolled; 178 (89%) completed follow?up. At baseline, 41% of participants selected the gel as their most preferred product and 61% selected the ring as least preferred. During the crossover period, most (82% to 85%) self?reported using each product at least once a week, although only half the time with sex. Objective biomarker data confirmed adequate use of all products. After trying each product, rankings changed with the film, ring, insert and gel being selected by 29%, 28%, 26% and 16% respectively. Choice varied significantly by country (p < 0.001): More Zimbabweans chose the film (45%), and more South Africans chose the insert (34%). Among women choosing the ring, 88% reported using it every time with sex. By contrast, self?reported adherence was lower for ?on?demand? (coitally associated) products, with 40% to 55% using them every time during sex (p < 0.001). Conclusions: Preferences for these four dosage forms varied before and after use, and both within and across countries ? there was no clear favourite ? indicating the need for a range of options for end?users. The ring's popularity increased the most with use, was the second most preferred delivery system, and per self?report, provided more coverage during sex. These end?user perspectives provide important information to product developers and funding agencies., Introduction Adolescents and young women in Africa are at disproportionately high risk for HIV acquisition and the identification and delivery of safe, effective female?initiated prevention interventions is a public health [...]

Background Viruses can evade immune surveillance, but the underlying mechanisms are insufficiently understood. Here, we sought to understand the mechanisms by which natural killer (NK) cells recognize HIV-1-infected cells and how this virus can evade NK-cell-mediated immune pressure. Methods and Findings Two sequence mutations in p24 Gag associated with the presence of specific KIR/HLA combined genotypes were identified in HIV-1 clade C viruses from a large cohort of infected, untreated individuals in South Africa (n = 392), suggesting viral escape from KIR+ NK cells through sequence variations within HLA class I--presented epitopes. One sequence polymorphism at position 303 of p24 Gag ([T.sub.[Gag.sub.303]V]), selected for in infected individuals with both KIR2DL3 and [HLA-C.sup.*] 03:04, enabled significantly better binding of the inhibitory KIR2DL3 receptor to [HLA-C.sup.*] 03:04-expressing cells presenting this variant epitope compared to the wild-type epitope (wild-type mean 18.01 ± 10.45 standard deviation [SD] and variant mean 44.67 ± 14.42 SD, p = 0.002). Furthermore, activation of primary KIR2DL3+ NK cells from healthy donors in response to [HLA-C.sup.*] 03:04+ target cells presenting the variant epitope was significantly reduced in comparison to cells presenting the wild-type sequence (wild-type mean 0.78 [+ or -] 0.07 standard error of the mean [SEM] and variant mean 0.63 ± 0.07 SEM, p = 0.012). Structural modeling and surface plasmon resonance of KIR/ peptide/HLA interactions in the context of the different viral sequence variants studied supported these results. Future studies will be needed to assess processing and antigen presentation of the investigated HIV-1 epitope in natural infection, and the consequences for viral control. Conclusions These data provide novel insights into how viruses can evade NK cell immunity through the selection of mutations in HLA-presented epitopes that enhance binding to inhibitory NKcell receptors. Better understanding of the mechanisms by which HIV-1 evades NK-cell-mediated immune pressure and the functional validation of a structural modeling approach will facilitate the development of novel targeted immune interventions to harness the antiviral activities of NK cells., Introduction Natural killer (NK) cells are an important component of the antiviral innate immune response. They have the ability to lyse target cells without prior antigen sensitization and to regulate [...]

Partner notification and treatment are essential components of sexually transmitted infection (STI) management, but little is known about such practices among adolescents and young adults. Using data from a prospective cohort study (AYAZAZI) of youth aged 16-24 years in Durban, South Africa, we assessed the STI care cascade across participant diagnosis, STI treatment, partner notification, and partner treatment; index recurrent STI and associated factors; and reasons for not notifying partner of STI. Participants completed laboratory-based STI screening (Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, Trichomonas vaginalis) at enrollment and at 12 months. Of the 37/216 participants with STI (17%), 27/37 (73%) were women and 10/37 (27%) were men. Median age was 19 years (IQR: 18-20). Of the participants with STI, 23/37 (62%) completed a Treatment and Partner Tracing Survey within 6 months of diagnosis. All survey participants reported completing STI treatment (100%), 17/23 (74%) notified a partner, and 6/23 (35%) reported partner treatment. Overall, 4/23 (11%) participants had 12-month recurrent C. trachomatis infection, with no association with partner notification or treatment. Stigma and lack of STI knowledge were reasons for not notifying partner of STI. STI partner notification and treatment is a challenge among youth. Novel strategies are needed to overcome barriers along the STI care cascade. [ABSTRACT FROM AUTHOR]

HIV-1 viremia has been shown to induce several phenotypic and functional abnormalities in natural killer (NK) cells. To assess immune defects associated with HIV viremia, we examined NK cell function, differentiation status, and phenotypic alterations based on expression of inhibitory and activating receptors on NK cells in HIV-1 subtype C chronically infected participants from Durban, South Africa. NK cell phenotypic profiles were characterized by assessing sialic acid-binding immunoglobulin-like lectin-7 (Siglec-7), NKG2A, and NKG2C markers on frozen peripheral blood mononuclear cells from viremic, antiretroviral therapy (ART)-naive HIV-1 chronically infected participants ( n = 23), HIV-1 chronically infected participants who had been on combination antiretroviral therapy (cART) for at least 12 months ( n = 23) compared with healthy donors ( n = 23). NK cell differentiation was assessed by measurement of killer immunoglobulin receptor (KIR) and NKG2A expression; CD57 and CD107a measurements were carried out in HIV viremic and healthy donors. All phenotypic and functional assessments were analyzed by using multicolor flow cytometry. HIV-1-infected participants displayed greater frequencies of the CD56−CD16+ (CD56negative) NK cell subset compared with healthy donors ( p < .0001). Downregulation of Siglec-7 and NKG2A and upregulation of NKG2C were more pronounced in the CD56negative NK cell subset of viremic participants. The CD56negative subset demonstrated a differentiated (KIR+NKG2A−) phenotype with reduced CD57 expression and lower degranulation capacity in HIV-1-infected participants compared with healthy donors. HIV-1 infection induces the expansion of the CD56negative NK cell subset marked by altered receptor expression profiles that are indicative of impaired function and may explain the overall NK cell dysfunction observed in chronic HIV-1 infection. [ABSTRACT FROM AUTHOR]

In South Africa, various point-of-care hemoglobin meters are used. However, the regulatory framework for approval, implementation and oversight of use of point-of-care hemoglobin meters is suboptimal. We assessed the diagnostic accuracy of the HemoCue Hb 301, STAT-Site MHgb and URIT-12 point-of-care hemoglobin meters, compared to a central laboratory based reference assay, in a central laboratory and a community based clinic in Durban, South Africa. Differences in performance of the point-of-care assays, compared to the reference assay, were more pronounced in the community based clinic. Results were reasonable for the HemoCue Hb 301, but poor for the STAT-Site MHgb and the URIT-12. Poor test performance of point-of-care hemoglobin meters, and inadequate evaluations and oversight in South Africa, leads to suboptimal clinical care and clinical research, and increased costs. There is a need for proper evaluation and quality assurance of point-of-care tests, the results of which should be made widely available to key stakeholders. [ABSTRACT FROM AUTHOR]

Monitoring of latent Mycobacterium tuberculosis infection may prevent disease. We tested an ESAT-6 and CFP-10-specific IFN-\(\gamma\) Elispot assay (RD1-Elispot) on 163 HIV-infected individuals living in a TB-endemic setting. An RD1-Elispot was performed every 3 months for a period of 3–21 months. 62% of RD1-Elispot negative individuals were positive by cultured Elispot. Fluctuations in T cell response were observed with rates of change ranging from −150 to +153 spot-forming cells (SFC)/200,000 PBMC in a 3-month period. To validate these responses we used an RD1-specific real time quantitative PCR assay for monokine-induced by IFN-\(\gamma\) (MIG) and IFN-\(\gamma\) inducible protein-10 (IP10) (MIG: r = 0.6527, p = 0.0114; IP-10: r = 0.6967, p = 0.0056; IP-10+MIG: r = 0.7055, p = 0.0048). During follow-up 30 individuals were placed on ARVs and 4 progressed to active TB. Fluctuations in SFC did not correlate with CD4 count, viral load, treatment initiation, or progression to active TB. The RD1-Elispot appears to have limited value in this setting.

An abstract of the article "Phenotypic and Functional Characteristics of Siglec-7, NKG2A and NKG2C Expressing NK Cells in Chronic HIV-1 Clade C Infection" by Michael Z. Zulu and colleagues is presented.

Background: There are gaps in uptake of, adherence to, and persistence in the use of preexposure prophylaxis for human immunodeficiency virus (HIV) prevention among cisgender women., Methods: We conducted a phase 3, double-blind, randomized, controlled trial involving adolescent girls and young women in South Africa and Uganda. Participants were assigned in a 2:2:1 ratio to receive subcutaneous lenacapavir every 26 weeks, daily oral emtricitabine-tenofovir alafenamide (F/TAF), or daily oral emtricitabine-tenofovir disoproxil fumarate (F/TDF; active control); all participants also received the alternate subcutaneous or oral placebo. We assessed the efficacy of lenacapavir and F/TAF by comparing the incidence of HIV infection with the estimated background incidence in the screened population and evaluated relative efficacy as compared with F/TDF., Results: Among 5338 participants who were initially HIV-negative, 55 incident HIV infections were observed: 0 infections among 2134 participants in the lenacapavir group (0 per 100 person-years; 95% confidence interval [CI], 0.00 to 0.19), 39 infections among 2136 participants in the F/TAF group (2.02 per 100 person-years; 95% CI, 1.44 to 2.76), and 16 infections among 1068 participants in the F/TDF group (1.69 per 100 person-years; 95% CI, 0.96 to 2.74). Background HIV incidence in the screened population (8094 participants) was 2.41 per 100 person-years (95% CI, 1.82 to 3.19). HIV incidence with lenacapavir was significantly lower than background HIV incidence (incidence rate ratio, 0.00; 95% CI, 0.00 to 0.04; P<0.001) and than HIV incidence with F/TDF (incidence rate ratio, 0.00; 95% CI, 0.00 to 0.10; P<0.001). HIV incidence with F/TAF did not differ significantly from background HIV incidence (incidence rate ratio, 0.84; 95% CI, 0.55 to 1.28; P = 0.21), and no evidence of a meaningful difference in HIV incidence was observed between F/TAF and F/TDF (incidence rate ratio, 1.20; 95% CI, 0.67 to 2.14). Adherence to F/TAF and F/TDF was low. No safety concerns were found. Injection-site reactions were more common in the lenacapavir group (68.8%) than in the placebo injection group (F/TAF and F/TDF combined) (34.9%); 4 participants in the lenacapavir group (0.2%) discontinued the trial regimen owing to injection-site reactions., Conclusions: No participants receiving twice-yearly lenacapavir acquired HIV infection. HIV incidence with lenacapavir was significantly lower than background HIV incidence and HIV incidence with F/TDF. (Funded by Gilead Sciences; PURPOSE 1 ClinicalTrials.gov number, NCT04994509.)., (Copyright © 2024 Massachusetts Medical Society.)

HIV-1 viremia has been shown to induce several phenotypic and functional abnormalities in natural killer (NK) cells. To assess immune defects associated with HIV viremia, we examined NK cell function, differentiation status, and phenotypic alterations based on expression of inhibitory and activating receptors on NK cells in HIV-1 subtype C chronically infected participants from Durban, South Africa. NK cell phenotypic profiles were characterized by assessing sialic acid-binding immunoglobulin-like lectin-7 (Siglec-7), NKG2A, and NKG2C markers on frozen peripheral blood mononuclear cells from viremic, antiretroviral therapy (ART)-naive HIV-1 chronically infected participants (n = 23), HIV-1 chronically infected participants who had been on combination antiretroviral therapy (cART) for at least 12 months (n = 23) compared with healthy donors (n = 23). NK cell differentiation was assessed by measurement of killer immunoglobulin receptor (KIR) and NKG2A expression; CD57 and CD107a measurements were carried out in HIV viremic and healthy donors. All phenotypic and functional assessments were analyzed by using multicolor flow cytometry. HIV-1-infected participants displayed greater frequencies of the CD56 - CD16 + (CD56negative) NK cell subset compared with healthy donors (p < .0001). Downregulation of Siglec-7 and NKG2A and upregulation of NKG2C were more pronounced in the CD56negative NK cell subset of viremic participants. The CD56negative subset demonstrated a differentiated (KIR + NKG2A - ) phenotype with reduced CD57 expression and lower degranulation capacity in HIV-1-infected participants compared with healthy donors. HIV-1 infection induces the expansion of the CD56negative NK cell subset marked by altered receptor expression profiles that are indicative of impaired function and may explain the overall NK cell dysfunction observed in chronic HIV-1 infection.