Intrinsic risk factors for alpha-gal syndrome in a case-control study, 2019 to 2020.

BACKGROUND: Alpha-gal syndrome (AGS) is an allergy to galactose-α-1,3-galactose (alpha-gal), a carbohydrate found in most mammals. Evidence indicates that AGS develops after a tick bite, and in the United States, AGS is most associated with bites from Amblyomma americanum (lone star tick); however, not all persons bitten by ticks develop clinical AGS. OBJECTIVE: To investigate intrinsic risk factors associated with the development of AGS. METHODS: We performed a case-control study among adults presenting for diagnosis or management of AGS at an allergy clinic in North Carolina during 2019 to 2020 and compared them with controls enrolled from 2 nearby internal medicine clinics. A questionnaire gathered epidemiologic and tick exposure data, and blood was obtained for alpha-gal-specific IgE and other testing. RESULTS: The 82 enrolled case patients and 191 controls did not differ significantly by age or sex. Case patients were more likely than controls to have A or O blood types (non B-antigen), have experienced childhood allergies, and have a family history of AGS and other food allergies. Case patients were also more likely to report experiencing long healing times for insect bites or stings and a family history of allergy to stinging or biting insects. CONCLUSION: This study suggested that intrinsic factors contribute to risk of developing AGS. Some traits are genetic, but common behaviors among households and family units likely also contribute. Identification of these risk factors can inform personal risk, aid health care providers in understanding susceptible populations, and contribute to ongoing understanding of AGS epidemiology.

Temporal trends and transmission dynamics of pre-treatment HIV-1 drug resistance within and between risk groups in Kenya, 1986-2020.

BACKGROUND: Evidence on the distribution of pre-treatment HIV-1 drug resistance (HIVDR) among risk groups is limited in Africa. We assessed the prevalence, trends and transmission dynamics of pre-treatment HIVDR within and between MSM, people who inject drugs (PWID), female sex workers (FSWs), heterosexuals (HETs) and perinatally infected children in Kenya. METHODS: HIV-1 partial pol sequences from antiretroviral-naive individuals collected from multiple sources between 1986 and 2020 were used. Pre-treatment reverse transcriptase inhibitor (RTI), PI and integrase inhibitor (INSTI) mutations were assessed using the Stanford HIVDR database. Phylogenetic methods were used to determine and date transmission clusters. RESULTS: Of 3567 sequences analysed, 550 (15.4%, 95% CI: 14.2-16.6) had at least one pre-treatment HIVDR mutation, which was most prevalent amongst children (41.3%), followed by PWID (31.0%), MSM (19.9%), FSWs (15.1%) and HETs (13.9%). Overall, pre-treatment HIVDR increased consistently, from 6.9% (before 2005) to 24.2% (2016-20). Among HETs, pre-treatment HIVDR increased from 6.6% (before 2005) to 20.2% (2011-15), but dropped to 6.5% (2016-20). Additionally, 32 clusters with shared pre-treatment HIVDR mutations were identified. The majority of clusters had R0 ≥ 1.0, indicating ongoing transmissions. The largest was a K103N cluster involving 16 MSM sequences sampled between 2010 and 2017, with an estimated time to the most recent common ancestor (tMRCA) of 2005 [95% higher posterior density (HPD), 2000-08], indicating propagation over 12 years. CONCLUSIONS: Compared to HETs, children and key populations had higher levels of pre-treatment HIVDR. Introduction of INSTIs after 2017 may have abrogated the increase in pre-treatment RTI mutations, albeit in the HET population only. Taken together, our findings underscore the need for targeted efforts towards equitable access to ART for children and key populations in Kenya.

Multi-Model Prediction of West Nile Virus Neuroinvasive Disease With Machine Learning for Identification of Important Regional Climatic Drivers.

West Nile virus (WNV) is the leading cause of mosquito-borne illness in the continental United States (CONUS). Spatial heterogeneity in historical incidence, environmental factors, and complex ecology make prediction of spatiotemporal variation in WNV transmission challenging. Machine learning provides promising tools for identification of important variables in such situations. To predict annual WNV neuroinvasive disease (WNND) cases in CONUS (2015-2021), we fitted 10 probabilistic models with variation in complexity from naïve to machine learning algorithm and an ensemble. We made predictions in each of nine climate regions on a hexagonal grid and evaluated each model's predictive accuracy. Using the machine learning models (random forest and neural network), we identified the relative importance and variation in ranking of predictors (historical WNND cases, climate anomalies, human demographics, and land use) across regions. We found that historical WNND cases and population density were among the most important factors while anomalies in temperature and precipitation often had relatively low importance. While the relative performance of each model varied across climatic regions, the magnitude of difference between models was small. All models except the naïve model had non-significant differences in performance relative to the baseline model (negative binomial model fit per hexagon). No model, including the ensemble or more complex machine learning models, outperformed models based on historical case counts on the hexagon or region level; these models are good forecasting benchmarks. Further work is needed to assess if predictive capacity can be improved beyond that of these historical baselines.

A cross-sectional survey exploring HIV and HCV prevalence among men who purchase sex in Dnipro, Ukraine.

BACKGROUND: HIV programming in Ukraine largely targets "key population" groups. Men who purchase sex are not directly reached. The aim of our study was to explore the prevalence of sexually transmitted and blood-borne infections (STBBIs) among men who purchase sex from female sex workers. METHODS: Following geographic mapping and population size estimation at each "hotspot", we conducted a cross-sectional bio-behavioural survey with men who purchase sex between September 2017 and March 2018 in Dnipro, Ukraine. Eligibility criteria included purchasing sex services at a "hotspot" and being ≥ 18 years. Participants completed a structured questionnaire, followed by HIV/HCV rapid testing and a dried blood spot (DBS) sample collection for confirmatory serology. RESULTS: The study enrolled 370 participants. The median age was 32 (interquartile range [IQR] = 27-38) and the median age of first purchase of sexual services was 22 (IQR = 19-27). Over half (56%) of participants reported ever testing for HIV; four participants (2%, N = 206) reported having tested positive for HIV, with three out of the four reporting being on ART. Forty percent of participants had ever tested for HCV, with three (2%, N = 142) having ever tested positive for HCV. In DBS testing, nine participants (2.4%) tested positive for HIV and 24 (6.5%) tested positive for ever having an HCV infection. CONCLUSION: Prevalence of HIV and HCV in this population was high. Given high rates of study enrolment and testing, efforts should be made to reach men who purchase sex with expanded STBBI programming.

Host genetic variation at a locus near CHD1L impacts HIV sequence diversity in a South African population.

IMPORTANCE: It has been previously shown that genetic variants near CHD1L on chromosome 1 are associated with reduced HIV VL in African populations. However, the impact of these variants on viral diversity and how they restrict viral replication are unknown. We report on a regional association analysis in a South African population and show evidence of selective pressure by variants near CHD1L on HIV RT and gag. Our findings provide further insight into how genetic variability at this locus contributes to host control of HIV in a South African population.

Blood monocyte and dendritic cell profiles among people living with HIV with Mycobacterium tuberculosis co-infection.

BACKGROUND: Understanding the complex interactions of the immune response mediated by Mycobacterium tuberculosis and HIV co-infection is fundamental to disease biomarker discovery, vaccine, and drug development. Using flow cytometry, we characterized the frequencies and phenotypic differences in monocytes and dendritic cell populations using peripheral blood mononuclear cells from individuals with recurrent, active pulmonary tuberculosis with and without coexisting HIV infection (CAPRISA 011, Clinicaltrials.gov, NCT02114684, 29/01/2014) and compared them to samples from HIV positive individuals and healthy controls. Additionally, we assessed the associations between the frequency of monocyte and dendritic cell subsets and time to culture conversion and cavitary disease in patients with active TB using a cox proportional hazards and logistic regression models. RESULTS: Compared to healthy controls, the frequency of total monocytes (HLA-DR + CD14 +) was significantly higher in the TB/HIV and TB groups and the frequency of dendritic cells (HLA-DR + CD14-) was significantly higher in TB/HIV and HIV groups. We observed significant variation in the expression of CCR2, CD40, CD11b, CD86, CD163, CX3CR1 across different cell subsets in the four study groups. Increase in CCR2, CD11b and CD40 was associated with active TB infection, while decrease in CX3CR1 and increase in CD163 was associated with HIV infection. Expression of CX3CR1 (aHR 0.98, 95% CI 0.963 - 0.997, p = 0.019) on non-classical monocytes associated with longer time to TB culture conversion in the multivariable model correcting for randomization arm, age, sex, HIV status, lung cavitation, alcohol use, smoking and BMI. Higher surface expression of CD86 (aOR 1.017, 95% CI 1.001 - 1.032, p = 0.033) on intermediate monocytes associated with the presence of lung cavitation, while higher expression of transitional monocytes (aOR 0.944, 95% CI 0.892 - 0.999, p = 0.047) associated with the absence of lung cavitation in the multivariable model. CONCLUSION: These data provide valuable insight into the heterogenous role of monocyte and dendritic cells in TB and HIV infections.

Immune resilience despite inflammatory stress promotes longevity and favorable health outcomes including resistance to infection.

Some people remain healthier throughout life than others but the underlying reasons are poorly understood. Here we hypothesize this advantage is attributable in part to optimal immune resilience (IR), defined as the capacity to preserve and/or rapidly restore immune functions that promote disease resistance (immunocompetence) and control inflammation in infectious diseases as well as other causes of inflammatory stress. We gauge IR levels with two distinct peripheral blood metrics that quantify the balance between (i) CD8+ and CD4+ T-cell levels and (ii) gene expression signatures tracking longevity-associated immunocompetence and mortality-associated inflammation. Profiles of IR metrics in ~48,500 individuals collectively indicate that some persons resist degradation of IR both during aging and when challenged with varied inflammatory stressors. With this resistance, preservation of optimal IR tracked (i) a lower risk of HIV acquisition, AIDS development, symptomatic influenza infection, and recurrent skin cancer; (ii) survival during COVID-19 and sepsis; and (iii) longevity. IR degradation is potentially reversible by decreasing inflammatory stress. Overall, we show that optimal IR is a trait observed across the age spectrum, more common in females, and aligned with a specific immunocompetence-inflammation balance linked to favorable immunity-dependent health outcomes. IR metrics and mechanisms have utility both as biomarkers for measuring immune health and for improving health outcomes.

Geographical Associations of HIV Prevalence in Female Sex Workers From Nairobi, Kenya (2014-2017).

BACKGROUND: Kenya's HIV epidemic is heterogeneously distributed. Although HIV incidence in Kenya has shown signs of recent decline, focused interventions are still needed for female sex workers (FSWs). Geospatially informed approaches have been advocated for targeted HIV prevention. We quantified heterogeneity in HIV burden in Nairobi-based FSWs by place of origin within Kenya and hotspots and residence within Nairobi. METHODS: Data were collected as part of enrolment in the Sex Workers Outreach Program in Nairobi between 2014 and 2017. Prevalence ratios were used to quantify the risk of HIV by high-prevalence counties using modified Poisson regression analyses. Crude and fully adjusted models were fitted to the data. In heterogeneity analyses, hotspots and residences were aggregated to the Nairobi constituency level (n = 17). Inequality in the geographic distribution of HIV prevalence was measured using the Gini coefficient. RESULTS: A total of 11,899 FSWs were included. Overall HIV prevalence was 16%. FSWs originating from a high-prevalence country were at 2-fold increased risk of living with HIV in adjusted analysis (prevalence ratio 1.95; 95% CI: 1.76 to 2.17). HIV prevalence was also highly heterogeneous by hotspot, ranging from 7% to 52% by hotspot (Gini coefficient: 0.37; 95% CI: 0.23 to 0.50). By contrast, the constituency of residence had a Gini coefficient of 0.08 (95% CI: 0.06 to 0.10), suggesting minimal heterogeneity by residence. CONCLUSION: HIV prevalence in FSWs is heterogeneous by place of work within Nairobi and by county of birth within Kenya. As HIV incidence declines and financial commitments flatline, tailoring interventions to FSWs at highest HIV risk becomes increasingly important.

High prevalence of vaccine-preventable anal human papillomavirus infections is associated with HIV infection among gay, bisexual, and men who have sex with men in Nairobi, Kenya.

BACKGROUND: Human papillomavirus (HPV) infection is associated with anal cancers and is more prevalent in gay, bisexual, and men who have sex with men (gbMSM), partly due to their vulnerability to HIV infection. Baseline HPV genotype distributions and risk factors can inform the design of next-generation HPV vaccines to prevent anal cancer. METHODS: A cross-sectional study was conducted among gbMSM receiving care at a HIV/STI clinic in Nairobi, Kenya. Anal swabs were genotyped using a Luminex microsphere array. Multiple logistic regression methods were used to identify risk factors for four HPV outcomes (any HPV, any HR-HPV, and 4- and 9-valent vaccine-preventable HPVs). RESULTS: Among 115 gbMSM, 51 (44.3%) were HIV-infected. Overall HPV prevalence was 51.3%; 84.3% among gbMSM living with HIV and 24.6% among gbMSM without HIV (p < 0.001). One-third (32.2%) had HR-HPV and the most prevalent vaccine-preventable HR-HPV genotypes were 16, 35, 45, and 58. HPV-18 was uncommon (n = 2). The 9-valent Gardasil vaccine would have prevented 61.0% of HPV types observed in this population. In multivariate analyses, HIV status was the only significant risk factor for any HPV (adjusted odds ratio [aOR]:23.0, 95% confidence interval [95% CI]: 7.3-86.0, p < 0.001) and for HR-HPV (aOR: 8.9, 95% CI: 2.8-36.0, p < 0.001). Similar findings were obtained for vaccine-preventable HPVs. Being married to a woman significantly increased the odds of having HR-HPV infections (aOR: 8.1, 95% CI: 1.6-52.0, p = 0.016). CONCLUSIONS: GbMSM living with HIV in Kenya are at higher risk of anal HPV infections including genotypes that are preventable with available vaccines. Our findings support the need for a targeted HPV vaccination campaign in this population.

Nonoptimal bacteria species induce neutrophil-driven inflammation and barrier disruption in the female genital tract.

Neutrophil recruitment and activation within the female genital tract are often associated with tissue inflammation, loss of vaginal epithelial barrier integrity, and increased risk for sexually transmitted infections, such as HIV-1. However, the direct role of neutrophils on vaginal epithelial barrier function during genital inflammation in vivo remains unclear. Using complementary proteome and immunological analyses, we show high neutrophil influx into the lower female genital tract in response to physiological surges in progesterone, stimulating distinct stromal, immunological, and metabolic signaling pathways. However, despite the release of extracellular matrix-modifying proteases and inflammatory mediators, neutrophils contributed little to physiological mucosal remodeling events such as epithelial shedding or re-epithelialization during transition from diestrus to estrus phase. In contrast, the presence of bacterial vaginosis-associated bacteria resulted in a rapid and sustained neutrophil recruitment, resulting in vaginal epithelial barrier leakage and decreased cell-cell junction protein expression in vivo. Thus, neutrophils are important mucosal sentinels that rapidly respond to various biological cues within the female genital tract, dictating the magnitude and duration of the ensuing inflammatory response at steady state and during disease processes.

HIV acquisition prior to entry into formal sex work: inference from next-generation viral sequencing.

OBJECTIVE: To infer the timing of HIV acquisition in relation to self-reported events in the sexual life course of adolescent girls and young women (AGYW) who self-identify as female sex workers (FSW) in Mombasa, Kenya. DESIGN: Next-generation viral sequencing of samples of AGYW living with HIV in the Transitions study, a cross-sectional bio-behavioural survey of AGYW aged 14-24 years in Mombasa, Kenya. METHOD: Dried blood spot specimens were collected from study participants ( n  = 37, all FSW). A portion of the HIV pol gene was sequenced using an in-house next-generation sequencing assay for HIV drug resistance mutation genotyping. Estimated time since infection (ETI) was inferred using the HIV EVO web-based tool ( https://hiv.biozentrum.unibas.ch/ETI/ ), and data on self-reported events were obtained from the survey. RESULTS: The median ETI among FSW was 3.4 (interquartile range = 1.7, 6.3) years, with a median ETI of 1.5 years prior to entry into formal sex work. We estimated that 74.1% (95% confidence interval = 53.7-88.9%) of participants living with HIV and who self-identified as FSW likely acquired HIV prior to self-identification as a sex worker. CONCLUSIONS: Findings suggest a large fraction of prevalent HIV infection among AGYW engaged in sex work stems from acquisition prior to entry into formal sex work. Current HIV prevention programs tailored for sex workers may miss key opportunities for HIV prevention as they are designed to reach women after entry into formal sex work, signaling a need for tailored programs to reach high-risk AGYW earlier on in their sexual life course.

Non-Lactobacillus-Dominant and Polymicrobial Vaginal Microbiomes Are More Common in Younger South African Women and Predictive of Increased Risk of Human Immunodeficiency Virus Acquisition.

BACKGROUND: Adolescent girls and young women aged 15‒24 years in sub-Saharan Africa are at disproportionate risk of human immunodeficiency virus (HIV) infection. Given the known association between vaginal microbial dysbiosis and HIV susceptibility, we performed an age-stratified analysis of the vaginal microbiome in South African women and compared this to their risk of HIV acquisition. METHODS: Vaginal microbiome data were generated by mass spectrometry-based proteomic analysis of cervicovaginal lavages collected from participants (n = 688) in the Centre for the AIDS Programme of Research in South Africa (CAPRISA) 004 trial. Participants were grouped by age (18-19 years, n = 93; 20-24 years, n = 326; 25-41 years, n = 269). RESULTS: Four microbiome types were identified based on predominant taxa, including Lactobacillus crispatus (CST-LC, 12.2%), Lactobacillus iners (CST-LI, 43.6%), Gardnerella vaginalis (CST-GV, 26.6%), or polymicrobial (CST-PM, 15.1%). Women aged 18-19 and 20-24 years had increased CST-PM and a non-Lactobacillus-dominant microbiome compared to those 25-41 years (odds ratio [OR], 3.14 [95% confidence interval {CI}, 1.12-7.87], P = .017; OR, 2.81 [95% CI, 1.07-7.09], P = .038, respectively; and OR, 1.65 [95% CI, 1.02-2.65], P = .028; OR, 1.40 [95% CI, 1.01-1.95], P = .030, respectively). The HIV incidence rate of women with CST-PM microbiome was 7.19-fold higher compared to women with CST-LC (hazard ratio [HR], 7.19 [95% CI, 2.11-24.5], P = .00162), which was also consistent in women aged 20-24 years (HR, 4.90 [95% CI, 1.10-21.9], P = .0375). CONCLUSIONS: Younger women were more likely to have a higher-risk polymicrobial microbiome suggesting that vaginal microbiota are contributing to increased HIV-1 susceptibility in this group. CLINICAL TRIALS REGISTRATION: NCT00441298.

Zika virus as a cause of birth defects: Were the teratogenic effects of Zika virus missed for decades?

Zika virus (ZIKV) was identified as a teratogen in 2016 when an increase in severe microcephaly and other brain defects was observed in fetuses and newborns following outbreaks in French Polynesia (2013-2014) and Brazil (2015-2016) and among travelers to other countries experiencing outbreaks. Some have questioned why ZIKV was not recognized as a teratogen before these outbreaks: whether novel genetic changes in ZIKV had increased its teratogenicity or whether its association with birth defects had previously been undetected. Here we examine the evidence for these two possibilities. We describe evidence for specific mutations that arose before the French Polynesia outbreak that might have increased ZIKV teratogenicity. We also present information on children born with findings consistent with congenital Zika syndrome (CZS) as early as 2009 and epidemiological evidence that suggests increases in CZS-type birth defects before 2013. We also explore reasons why a link between ZIKV and birth defects might have been missed, including issues with surveillance of ZIKV infections and of birth defects, challenges to ZIKV diagnostic testing, and the susceptibility of different populations to ZIKV infection at the time of pregnancy. Although it is not possible to prove definitively that ZIKV had teratogenic properties before 2013, several pieces of evidence support the hypothesis that its teratogenicity had been missed in the past. These findings emphasize the need for further investments in global surveillance for emerging infections and for birth defects so that infectious teratogens can be identified more expeditiously in the future.

Tick bite as a risk factor for alpha-gal-specific immunoglobulin E antibodies and development of alpha-gal syndrome.

BACKGROUND: The disaccharide galactose-α-1,3-galactose (alpha-gal) is expressed in mammals other than humans, apes, and old-world monkeys. In humans, elevated immunoglobulin E (IgE) antibodies specific for alpha-gal can result in allergic hypersensitivity known as alpha-gal syndrome (AGS). Case reports and series suggest that tick bites can induce alpha-gal-specific IgE (sIgE) antibodies. OBJECTIVE: To evaluate tick exposure as a risk factor for AGS and elevated alpha-gal sIgE level. METHODS: We conducted a case-control study comparing patients with AGS from a North Carolina allergy clinic with controls who were patients at a nearby internal medicine clinic. Cases and controls were administered a questionnaire to obtain information about demographics, home environment, outdoor activities, and recollection of tick bite. Serum samples taken at the time of enrollment were tested for total IgE, alpha-gal sIgE, and antibodies to other tick-borne pathogens. RESULTS: The patients with AGS were more likely to recall finding a tick on themselves (odds ratio [OR], 11.20; 95% confidence interval [CI], 4.97-25.15), live near wooded forest (OR, 2.27; 95% CI, 0.92-5.55), and spend 17 or more hours per week outdoors in wooded areas (OR, 5.58; 95% CI, 2.56-12.19). The patients with AGS were also more likely to report 4 or more tick bites (OR, 33.05; 95% CI, 9.92-155.12) and reactions at the site of tick bites (OR, 7.93; 95% CI, 3.74-16.80). Furthermore, elevated alpha-gal sIgE level was observed in 33% of the controls and was associated with tick exposure in the controls (OR, 4.25; 95% CI, 2.21-8.18). CONCLUSION: The results define tick bite as a risk factor for AGS and elevated alpha-gal sIgE level.

Clinical and laboratory features of patients diagnosed with alpha-gal syndrome-2010-2019.

BACKGROUND: Alpha-gal syndrome (AGS) is an IgE-mediated allergy to galactose-alpha-1,3-galactose. Clinical presentation ranges from hives to anaphylaxis; episodes typically occur 2-6 h after exposure to alpha-gal-containing products. In the United States, lone star tick bites are associated with the development of AGS. To characterize features of AGS, we evaluated a cohort of patients presenting for care at the University of North Carolina, focusing on symptoms, severity, and identifying features unique to specific alpha-gal-containing product exposures. METHODS: We performed a chart review and descriptive analysis of 100 randomly selected patients with AGS during 2010-2019. RESULTS: Median age at onset was 53 years, 56% were female, 95% reported White race, 86% reported a history of tick bite, and 75% met the criteria for anaphylaxis based on the involvement of ≥2 organ systems. Those reporting dairy reactions were significantly less likely to report isolated mucocutaneous symptoms (3% vs. 24%; ratio [95% CI]: 0.1 [0.1, 0.3]) than those who tolerated dairy, and were more likely to report gastrointestinal symptoms (79% vs. 59%; ratio [95% CI]: 1.3 [0.7, 2.6]), although this difference was not statistically significant. Dairy-tolerant patients demonstrated higher alpha-gal sIgE titers (as a percentage of total IgE) than dairy-reactive patients (GM 4.1 [95% CI: 2.7, 6.1] vs. GM 2.5 [95% CI: 1.3, 4.8], respectively; ratio -1.6 [95% CI: -1.0, 3.9]). CONCLUSION: While tick exposure is common in the southern United States, nearly all AGS patients reported a tick bite. Gastrointestinal symptoms were prominent among those reporting reactions to dairy. Anaphylaxis was common, underscoring the severity and need to raise awareness of AGS among patients and providers.

Changes in concentrations of cervicovaginal immune mediators across the menstrual cycle: a systematic review and meta-analysis of individual patient data.

BACKGROUND: Hormonal changes during the menstrual cycle play a key role in shaping immunity in the cervicovaginal tract. Cervicovaginal fluid contains cytokines, chemokines, immunoglobulins, and other immune mediators. Many studies have shown that the concentrations of these immune mediators change throughout the menstrual cycle, but the studies have often shown inconsistent results. Our understanding of immunological correlates of the menstrual cycle remains limited and could be improved by meta-analysis of the available evidence. METHODS: We performed a systematic review and meta-analysis of cervicovaginal immune mediator concentrations throughout the menstrual cycle using individual participant data. Study eligibility included strict definitions of the cycle phase (by progesterone or days since the last menstrual period) and no use of hormonal contraception or intrauterine devices. We performed random-effects meta-analyses using inverse-variance pooling to estimate concentration differences between the follicular and luteal phases. In addition, we performed a new laboratory study, measuring select immune mediators in cervicovaginal lavage samples. RESULTS: We screened 1570 abstracts and identified 71 eligible studies. We analyzed data from 31 studies, encompassing 39,589 concentration measurements of 77 immune mediators made on 2112 samples from 871 participants. Meta-analyses were performed on 53 immune mediators. Antibodies, CC-type chemokines, MMPs, IL-6, IL-16, IL-1RA, G-CSF, GNLY, and ICAM1 were lower in the luteal phase than the follicular phase. Only IL-1α, HBD-2, and HBD-3 were elevated in the luteal phase. There was minimal change between the phases for CXCL8, 9, and 10, interferons, TNF, SLPI, elafin, lysozyme, lactoferrin, and interleukins 1ß, 2, 10, 12, 13, and 17A. The GRADE strength of evidence was moderate to high for all immune mediators listed here. CONCLUSIONS: Despite the variability of cervicovaginal immune mediator measurements, our meta-analyses show clear and consistent changes during the menstrual cycle. Many immune mediators were lower in the luteal phase, including chemokines, antibodies, matrix metalloproteinases, and several interleukins. Only interleukin-1α and beta-defensins were higher in the luteal phase. These cyclical differences may have consequences for immunity, susceptibility to infection, and fertility. Our study emphasizes the need to control for the effect of the menstrual cycle on immune mediators in future studies.

Baseline host determinants of robust human HIV-1 vaccine-induced immune responses: A meta-analysis of 26 vaccine regimens.

BACKGROUND: The identification of baseline host determinants that associate with robust HIV-1 vaccine-induced immune responses could aid HIV-1 vaccine development. We aimed to assess both the collective and relative performance of baseline characteristics in classifying individual participants in nine different Phase 1-2 HIV-1 vaccine clinical trials (26 vaccine regimens, conducted in Africa and in the Americas) as High HIV-1 vaccine responders. METHODS: This was a meta-analysis of individual participant data, with studies chosen based on participant-level (vs. study-level summary) data availability within the HIV-1 Vaccine Trials Network. We assessed the performance of 25 baseline characteristics (demographics, safety haematological measurements, vital signs, assay background measurements) and estimated the relative importance of each characteristic in classifying 831 participants as High (defined as within the top 25th percentile among positive responders or above the assay upper limit of quantification) versus Non-High responders. Immune response outcomes included HIV-1-specific serum IgG binding antibodies and Env-specific CD4+ T-cell responses assessed two weeks post-last dose, all measured at central HVTN laboratories. Three variable importance approaches based on SuperLearner ensemble machine learning were considered. FINDINGS: Overall, 30.1%, 50.5%, 36.2%, and 13.9% of participants were categorized as High responders for gp120 IgG, gp140 IgG, gp41 IgG, and Env-specific CD4+ T-cell vaccine-induced responses, respectively. When including all baseline characteristics, moderate performance was achieved for the classification of High responder status for the binding antibody responses, with cross-validated areas under the ROC curve (CV-AUC) of 0.72 (95% CI: 0.68, 0.76) for gp120 IgG, 0.73 (0.69, 0.76) for gp140 IgG, and 0.67 (95% CI: 0.63, 0.72) for gp41 IgG. In contrast, the collection of all baseline characteristics yielded little improvement over chance for predicting High Env-specific CD4+ T-cell responses [CV-AUC: 0.53 (0.48, 0.58)]. While estimated variable importance patterns differed across the three approaches, female sex assigned at birth, lower height, and higher total white blood cell count emerged as significant predictors of High responder status across multiple immune response outcomes using Approach 1. Of these three baseline variables, total white blood cell count ranked highly across all three approaches for predicting vaccine-induced gp41 and gp140 High responder status. INTERPRETATION: The identified features should be studied further in pursuit of intervention strategies to improve vaccine responses and may be adjusted for in analyses of immune response data to enhance statistical power. FUNDING: National Institute of Allergy and Infectious Diseases (UM1AI068635 to YH, UM1AI068614 to GDT, UM1AI068618 to MJM, and UM1 AI069511 to MCK), the Duke CFAR P30 AI064518 to GDT, and National Institute of Dental and Craniofacial Research (R01DE027245 to JJK). This work was also supported by the Bill and Melinda Gates Foundation. The content is solely the responsibility of the authors and does not necessarily represent the official views of any of the funding sources.

Expansion of cytotoxic tissue-resident CD8+ T cells and CCR6+CD161+ CD4+ T cells in the nasal mucosa following mRNA COVID-19 vaccination.

Vaccines against SARS-CoV-2 have shown high efficacy in clinical trials, yet a full immunologic characterization of these vaccines, particularly within the human upper respiratory tract, is less well known. Here, we enumerate and phenotype T cells in nasal mucosa and blood using flow cytometry before and after vaccination with the Pfizer-BioNTech COVID-19 vaccine (n = 21). Tissue-resident memory (Trm) CD8+ T cells expressing CD69+CD103+ increase in number ~12 days following the first and second doses, by 0.31 and 0.43 log10 cells per swab respectively (p = 0.058 and p = 0.009 in adjusted linear mixed models). CD69+CD103+CD8+ T cells in the blood decrease post-vaccination. Similar increases in nasal CD8+CD69+CD103- T cells are observed, particularly following the second dose. CD4+ cells co-expressing CCR6 and CD161 are also increased in abundance following both doses. Stimulation of nasal CD8+ T cells with SARS-CoV-2 spike peptides elevates expression of CD107a at 2- and 6-months (p = 0.0096) post second vaccine dose, with a subset of donors also expressing increased cytokines. These data suggest that nasal T cells may be induced and contribute to the protective immunity afforded by this vaccine.

Viral suppression among pregnant adolescents and women living with HIV in rural KwaZulu-Natal, South Africa: a cross sectional study to assess progress towards UNAIDS indicators and Implications for HIV Epidemic Control.

BACKGROUND: South Africa has made significant progress in scaling up antiretroviral therapy (ART) to achieve the aspirational goal of HIV epidemic control. The aim of this study was to determine the prevalence of HIV, assess progress towards each of the Joint United Nations Programme on HIV/AIDS (UNAIDS) indicators and determine factors associated with achieving viral suppression among pregnant adolescents and women living with HIV in rural KwaZulu-Natal, South Africa. METHODS: Pregnant adolescents and women, 12 years and older seeking antenatal care at six primary health care clinics were enrolled in a cross-sectional study. Following written informed consent, structured questionnaires were administered, and finger-prick blood samples were collected for HIV antibody testing and viral load measurement. Viral suppression was defined as HIV viral load of < 400 copies per mL. RESULTS: Between Dec 2016 and March 2017, among the 546 enrolled participants, data for 545 were analysed. The overall HIV prevalence was 40.2% [95% Confidence Interval (CI) 36.1-44.3]. Age-stratified prevalence increased from 22.1% (95% CI, 15.9-30.0) in the 14-19 year age group to 63.9% (95% CI, 55.1-71.9) among women ≥ 30 years (Χ2 trend P < 0.0001). Of the HIV positive participants, 84.5% (95% CI, 79.0-88.8) knew their HIV positive status, 98.3% (95% CI 95.1-99.4) who knew their status were on ART, and of those on ART, 95.9% (95% CI 91.8-98.0) were virally suppressed. Among all HIV-positives 90.8% (95% CI, 86.3-94.0) had achieved viral suppression, whilst those in the 14-19 year age group were least likely to be virally suppressed at 82.8% (95% CI 65.5-92.4) compared to those in the older age groups. Married women compared to those unmarried were more likely to have achieved viral suppression (PRR) of 1.11 (95% CI 1.05-1.18), P < 0.001. CONCLUSIONS: The proportion of HIV positive pregnant women achieving viral suppression was encouraging though far short of the target towards achieving epidemic control. Importantly, adolescent pregnant women were less likely to know their HIV status and to achieve viral suppression, underscoring the public health implications of sustained risk of HIV transmission. Thus, greater effort and strong social support are essential to improve HIV knowledge of status and care continuum towards the goal to achieving HIV epidemic control. To "fast-track" the response to achieve HIV epidemic control and end the AIDS epidemic, the Joint United Nations Programme on HIV/AIDS (UNAIDS) set ambitious HIV testing and treatment targets for people living with HIV. Meeting these targets through scaling up testing for HIV, initiating and sustaining antiretroviral therapy (ART) to maintain viral suppression provides both therapeutic and preventive benefits with the potential to reduce HIV transmission. Viral suppression among pregnant adolescents and women living with HIV is crucial for the prevention of mother-to-child transmission of HIV including onward transmission to sexual partners. As a public health approach, in South Africa all pregnant women are offered routine HIV testing and immediate initiation of lifelong ART irrespective of CD4 cell count. It is, therefore, important to ascertain progress towards reaching the targets. The proportion of HIV positive pregnant adolescents and women achieving viral suppression was encouraging though far short of the target towards achieving epidemic control. Importantly, pregnant adolescents were less likely to know their HIV status and to achieve viral suppression, underscoring the public health implications of sustained risk of HIV transmission. Thus, greater effort and strong social support are essential to improve HIV knowledge of status and care continuum towards the goal to achieving HIV epidemic control.