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In October of 2020, researchers from around the world met online for the sixth annual International Workshop on Microbiome in HIV Pathogenesis, Prevention, and Treatment. New research was presented on the roles of the microbiome on immune response and HIV transmission and pathogenesis and the potential for alterations in the microbiome to decrease transmission and affect comorbidities. This article presents a summary of the findings reported.

ObjectiveThe rectal microbiome was examined to assess the relationship between the microbiome and liver disease in HIV-infection.DesignEighty-two HIV-1 mono-infected individuals from the PROSPEC-HIV-study (NCT02542020) were grouped into three liver health categories based on results of controlled attenuation parameter (CAP) and liver stiffness measurement (LSM) of transient elastography: normal (n = 30), steatosis (n = 30), or fibrosis (n = 22).MethodsLiver steatosis and fibrosis were defined by CAP at least 248 dB/m and LSM at least 8.0 kPa, respectively. 16S rRNA gene and whole genome shotgun metagenomic sequencing were performed on rectal swabs. Bacterial differences were assessed using zero-inflated negative binomial regression and random forests modeling; taxonomic drivers of functional shifts were identified using FishTaco.ResultsLiver health status explained four percentage of the overall variation (r2 = 0.04, P = 0.003) in bacterial composition. Participants with steatosis had depletions of Akkermansia muciniphila and Bacteroides dorei and enrichment of Prevotella copri, Finegoldia magna, and Ruminococcus bromii. Participants with fibrosis had depletions of Bacteroides stercoris and Parabacteroides distasonis and enrichment of Sneathia sanguinegens. In steatosis, functional analysis revealed increases in primary and secondary bile acid synthesis encoded by increased Eubacterium rectale, F. magna, and Faecalibacterium prausnitzii and decreased A. muciniphila, Bacteroides fragilis and B. dorei. Decreased folate biosynthesis was driven by similar changes in microbial composition.ConclusionHIV mono-infection with steatosis or fibrosis had distinct microbial profiles. Some taxa are similar to those associated with non-alcoholic fatty liver disease in HIV-negative populations. Further studies are needed to define the role of the gut microbiota in the pathogenesis of liver disease in HIV-infected persons.

Each year, a growing international collection of researchers meets at the NIH to share and discuss developments in the microbiome HIV story. This past year has seen continued progress toward a detailed understanding of host-microbe interactions both within and outside the field of HIV. Commensal microbes are being linked to an ever-growing list of maladies and physiologic states, including major depressive disorder, chronic kidney disease, and Parkinson disease. PubMed citations for "microbiome" are growing at an exponential rate with over 11,000 in 2018. Various microbial taxa have been associated with HIV infection, and some of these taxa associated with HIV infection have also been associated with systemic markers of inflammation in HIV infected individuals. Causality remains unclear however as environmental and behavioral factors may drive HIV risk, inflammation, and gut enterotype. Much of the work currently being done addresses potential mechanisms by which gut microbes influence immune and inflammatory pathways. No portion of the microbiome landscape has grown as rapidly as study of the interplay between gut microbes and response to cancer immunotherapy. As Dr. Wargo discussed in her keynote address, this area has opened the door to better understanding on how commensal microbes interact with the human immune system.

BackgroundAlterations in the gut microbiome have been associated with HIV infection, but the relative impact of HIV versus other factors on the gut microbiome has been difficult to determine in cross-sectional studies.MethodsTo address this, we examined the gut microbiome, serum metabolome, and cytokines longitudinally within 27 individuals before and during acute HIV using samples collected from several ongoing cohort studies. Matched control participants (n=28) from the same cohort studies without HIV but at similar behavioral risk were used for comparison.FindingsWe identified few changes in the microbiome during acute HIV infection, but did find alterations in serum metabolites involving secondary bile acid (lithocholate sulfate, glycocholenate sulfate) and amino acid metabolism (3-methyl-2-oxovalerate, serine, cysteine, N-acetylputrescine). Greater microbiome differences, including decreased Bacteroides spp and increased Megasphaera elsdenii, were seen when comparing pre-HIV infection visits to matched at-risk controls. Those who acquired HIV also had elevated inflammatory cytokines (TNF-α, B cell activating factor, IL-8) and bioactive lipids (palmitoyl-sphingosine-phosphoethanolamide and glycerophosphoinositol) prior to HIV acquisition compared to matched controls.InterpretationLongitudinal sampling identified pre-existing microbiome differences in participants with acute HIV compared to matched control participants observed over the same period. These data highlight the importance of increasing understanding of the role of the microbiome in HIV susceptibility.FundingThis work was supported by NIH/NIAID (K08AI124979; P30AI117943), NIH/NIDA (U01DA036267; U01DA036939; U01DA036926; U24DA044554), and NIH/NIMH (P30MH058107; R34MH105272).

Human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2) diagnostic testing algorithms recommended by the Centers for Disease Control involve up to three tests and rely mostly on detection of viral antigen and host antibody responses. HIV-1 p24 antigen/HIV-1/HIV-2 antibody-reactive specimens are confirmed with an immunochromatographic HIV-1/HIV-2 antibody differentiation assay, and negative or indeterminate results from the differentiation assay are resolved by an HIV-1-specific nucleic acid amplification test (NAT). The performance of a proposed alternative algorithm using the cobas HIV-1/HIV-2 qualitative NAT as the differentiation assay was evaluated in subjects known to be infected with HIV-1 (n = 876) or HIV-2 (n = 139), at low (n = 6,017) or high (n = 1,020) risk of HIV-1 infection, or at high-risk for HIV-2 infection (n = 498) (study A). The performance of the cobas HIV-1/HIV-2 qualitative test was also evaluated by comparison to an HIV-1 or HIV-2 alternative NAT (study B). The HIV-1 and HIV-2 overall percent agreements (OPA) in study A ranged from 95% to 100% in all groups. The positive percent agreements (PPA) for HIV-1 and HIV-2 were 100% (876/876) and 99.4% (167/168), respectively, for known positive groups. The negative percent agreement in the HIV low-risk group was 100% for both HIV-1 and HIV-2. In study B, the HIV-1 and HIV-2 OPA ranged from 99% to 100% in all groups evaluated (n = 183 to 1,030), and the PPA for HIV-1 and HIV-2 were 100% and 99.5%, respectively, for known positive groups. The cobas HIV-1/HIV-2 qualitative assay can discriminate between HIV-1 and HIV-2 based on HIV RNA and can be included in an alternative diagnostic algorithm for HIV.

To describe distributions of immune markers in children and young adults by sex and HIV status, and within groups, investigate associations of immune markers with bone density across Tanner stage. Using data and samples from 353 participants in a cross-sectional study in youth with perinatally acquired HIV (PHIV) and matched HIV-negative controls, distributions of inflammation and activation immune markers were described by sex and HIV status. Correlations and structural equation models (SEM) were used to explore marginal and multivariable associations of the immune markers with bone density and to assess whether patterns of association varied by sex and HIV status. Immune marker distributions did not differ by sex, but there were some differences by HIV status. Correlation patterns among bone, body composition, and immune markers were similar across the sex and HIV status groups. Conclusions from SEMs were limited by small sample sizes, but there was some indication that patterns of association between bone density and certain immune markers differed in male PHIV with more advanced Tanner stage compared to the other three groups. In conclusion, distributions of bone density, body composition, and immune markers may vary by sex and HIV status, although associations among these outcomes within sex and HIV status groups appear similar. Bone density of male PHIV appears to be more negatively affected than females, regardless of female HIV status. Larger longitudinal studies across Tanner stages are needed to further explore potential biological relationships between immune markers and bone density in youth living with HIV.

ObjectivesThe prevalence of obesity is rising among people living with HIV, which may synergistically increase inflammation and the risk of associated diseases. Disruption of gut bacterial communities may be one of the key drivers of this inflammation; however, the combined effects of HIV and obesity on the microbiome have not been explored.MethodsThis study included 381 men who have sex with men. Thirty-nine were HIV-positive and obese (H+O+), 143 were HIV-positive and nonobese, 64 were HIV-negative and obese, and 135 were HIV-negative and nonobese. Microbiome composition was assessed by targeted sequencing of the V4 region of the 16S ribosomal RNA (rRNA) gene using rectal swab samples. Inverse probability of treatment-weighted marginal structural models wereused to investigate differences in microbial composition between groups while controlling for numerous clinical and behavioural confounders.ResultsSignificant variability in microbial composition was explained by the combination of HIV and obesity, over and above each condition alone (R2 for the marginal contribution of the H+/O+ group=0.008; P=0.001). H+O+ participants had the highest ratios of Prevotella to Bacteroides, a pro-inflammatory enterotype that has been described in HIV infection and obesity independently. H+O+ participants had lower levels of Bacteroides and Veillonella than all other groups, suggesting a synergistic effect of HIV and obesity on these genera.ConclusionsOur findings support the hypothesis that HIV and obesity act together to disrupt gut microbial communities, which may help explain higher levels of generalized inflammation among people living with both HIV and obesity.

Author(s): Joseph Davey, Dvora L; Pintye, Jillian; Baeten, Jared M; Aldrovandi, Grace; Baggaley, Rachel; Bekker, Linda-Gail; Celum, Connie; Chi, Benjamin H; Coates, Thomas J; Haberer, Jessica E; Heffron, Renee; Kinuthia, John; Matthews, Lynn T; McIntyre, James; Moodley, Dhayendre; Mofenson, Lynne M; Mugo, Nelly; Myer, Landon; Mujugira, Andrew; Shoptaw, Steven; Stranix-Chibanda, Lynda; John-Stewart, Grace; PrEP in Pregnancy Working Group | Abstract: IntroductionHIV incidence is high during pregnancy and breastfeeding with HIV acquisition risk more than doubling during pregnancy and the postpartum period compared to when women are not pregnant. The World Health Organization recommends offering pre-exposure prophylaxis (PrEP) to pregnant and postpartum women at substantial risk of HIV infection. However, maternal PrEP national guidelines differ and most countries with high maternal HIV incidence are not offering PrEP. We conducted a systematic review of recent research on PrEP safety in pregnancy to inform national policy and rollout.MethodsWe used a standard Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) approach to conduct a systematic review by searching for completed, ongoing, or planned PrEP in pregnancy projects or studies from clinicaltrials.gov, PubMed and NIH RePORTER from 2014 to March 2019. We performed a systematic review of studies that assess tenofovir disoproxil fumarate (TDF)-based oral PrEP safety in pregnant and breastfeeding HIV-uninfected women.Results and discussionWe identified 14 completed (n = 5) and ongoing/planned (n = 9) studies that evaluate maternal and/or infant outcomes following PrEP exposure during pregnancy or breastfeeding. None of the completed studies found differences in pregnancy or perinatal outcomes associated with PrEP exposure. Nine ongoing studies, to be completed by 2022, will provide data on g6200 additional PrEP-exposed pregnancies and assess perinatal, infant growth and bone health outcomes, expanding by sixfold the data on PrEP safety in pregnancy. Research gaps include limited data on (1) accurately measured PrEP exposure within maternal and infant populations including drug levels needed for maternal protection; (2) uncommon perinatal outcomes (e.g. congenital anomalies); (3) infant outcomes such as bone growth beyond one year following PrEP exposure; (4) outcomes in HIV-uninfected women who use PrEP during pregnancy and/or lactation.ConclusionsExpanding delivery of PrEP is an essential strategy to reduce HIV incidence in pregnancy and breastfeeding women. Early safety studies of PrEP among pregnant women without HIV infection are reassuring and ongoing/planned studies will contribute extensive new data to bolster the safety profile of PrEP use in pregnancy. However, addressing research gaps is essential to expanding PrEP delivery for women in the context of pregnancy.

Methamphetamine (MA) use is a major public health problem in the United States, especially among people living with HIV (PLWH). Many MA-induced neurotoxic effects are mediated by inflammation and gut microbiota may play a role in this process, yet the effects of MA on the microbiome have not been adequately explored. Therefore, we performed 16S rRNA gene sequencing on rectal swab samples from 381 men who have sex with men, 48% of whom were PLWH and 41% of whom used MA. We compared microbiome composition between MA users and non-users while testing for potential interactions with HIV and controlling for numerous confounders using inverse probability of treatment weighting. We found that MA use explained significant variation in overall composition (R2 = 0.005, p = 0.008) and was associated with elevated Finegoldia, Parvimonas, Peptoniphilus, and Porphyromonas and reduced Butyricicoccus and Faecalibacterium, among others. Genera including Actinomyces and Streptobacillus interacted with HIV status, such that they were increased in HIV+ MA users. Finegoldia and Peptoniphilus increased with increasing frequency of MA use, among others. In summary, MA use was associated with a microbial imbalance favoring pro-inflammatory bacteria, including some with neuroactive potential and others that have previously been associated with poor HIV outcomes.

Both HIV infection and tenofovir disoproxil fumarate (TDF) treatment adversely impact bone metabolism and may lead to osteopenia, which has critical implications for youth with HIV (YWH). This study evaluates changes in the biomarkers of bone metabolism and inflammation among YWH receiving initial treatment with TDF- and non-TDF-containing antiretroviral therapies (ARTs). YWH [n = 23, median age 21 years (range 18–24), 87% male, 61% African American] were assessed for inflammatory and bone metabolism biomarkers at enrollment, after 48 weeks of TDF-containing ART, and 96 weeks of ART without TDF with continued viral suppression. Spearman's rank correlation evaluated biomarker associations. Bone alkaline phosphatase, parathyroid hormone, and osteopontin increased after TDF treatment. All fell after TDF was discontinued. Levels of RANKL and osteoprotegerin did not change throughout the study. There was little correlation between biomarkers of bone metabolism and either macrophage or lymphocyte activation at any time point. Our results establish baseline associations between bone metabolism and immune biomarkers for this population, and find that before CD4 T cell decline chronic inflammation does not perturb biomarkers of bone metabolism among YWH. The adverse effects of TDF on bone health may be marginal for YWH at the early stages of disease.

BackgroundHuman immunodeficiency virus type 1 (HIV-1) infection alters the human intestinal microbiome; however, behavioral factors driving these changes remain poorly defined. Here we examine the effects of substance use and sex behavior on the microbiome during HIV-1 infection.MethodsArchival rectal swab specimens, urine drug test results, and responses to substance use and sex behavior questionnaires were obtained from 37 HIV-positive participants at 2 time points, separated by 6 months, in a cohort examining the effects of substance use in men who have sex with men (MSM). Microbiome profiling was performed using 16S ribosomal RNA gene sequencing, and associations with behavioral factors were examined using 0-inflated negative binomial regression. Further analysis of selected variables of interest was performed using propensity scores to account for multiple confounders.ResultsUsing permutational multivariate analysis of variance, we found that receptive anal intercourse, methamphetamine use, and marijuana use were among the most important drivers of microbiome variation. Propensity score–adjusted analyses revealed that methamphetamine use and marijuana use displayed unique associations; methamphetamine use was associated with an increased abundance of Porphyromonas and Granulicatella organisms and a decreased abundance of Ruminococcus, Collinsella, and Parabacteroides organisms, whereas marijuana use was associated with an increased abundance of Ruminococcus, Clostridium cluster IV, Solobacterium, and Fusobacterium organisms and a decreased abundance of Acidaminococcus, Prevotella, Dialister, Anaerostipes, and Dorea organisms.ConclusionsDrug use and sex behavior are important factors associated with intestinal dysbiosis during chronic HIV-1 infection among young MSM.

OBJECTIVE The aim of this study was to estimate the long-term metabolic effects of initiating a lopinavir/ritonavir (LPV/r)-based regimen as a first-line therapy for HIV-infected children less than 3 years of age in resource-limited settings. DESIGN A prospective cohort study after conclusion of the P1060 randomized clinical trials (ClinicalTrials.gov Identifier: NCT00307151), with an overall follow-up of 7 years. METHODS Longitudinal total cholesterol and triglyceride measures were compared between 222 and 227 children randomized to initiate LPV/r and nevirapine (NVP)-based regimens, respectively. Adipokines (adiponectin and leptin) and biomarkers of inflammation [C-reactive protein and interleukin (IL)-6], microbial translocation (lipopolysaccharide) and immune activation (sCD14), measured in 117 participants at a median of 45 weeks of follow-up, were also compared by a randomized arm. RESULTS Mean total cholesterol and the percentage of participants with borderline or high total cholesterol was higher in the LPV/r arm from years 3 to 7 of follow-up than in the NVP arm (adjusted relative differences ranging from 10.9 to 23.4 mg/dl and adjusted relative risks ranging from a 60% increased risk to a more than four-fold increased risk for cholesterol ≥170 mg/dl at 7 years of follow-up). Initiation of a LPV/r-based regimen was not associated with high triglycerides over follow-up or large differences in markers of metabolic syndrome, inflammation, microbial translocation or immune activation. CONCLUSION Given the virologic superiority of LPV/r-based regimens in young children and open questions regarding the roll-out of dolutegravir in resource-limited settings, children are currently being maintained on LPV/r-based regimens. Our results suggest continual assessment of total cholesterol among young children initiating a LPV/r-based regimen to monitor cardiometabolic health.

OBJECTIVE We tested our hypothesis that abdominal obesity when associated with increased levels of systemic and central nervous system immunoinflammatory mediators contributes to neurocognitive impairment (NCI). DESIGN Cross-sectional. SETTING Six Academic Centers. PARTICIPANTS One hundred fifty-two patients with plasma HIV RNA

Background: Human milk oligosaccharides (HMOs) have multiple immunomodulatory functions that influence child health. Objective: In this study we investigated whether HMO composition influences survival to 2 y of age in HIV-infected and HIV-exposed, uninfected (HEU) children during and after breastfeeding. Methods: In the context of an early weaning trial in 958 HIV-infected women in Lusaka, Zambia, we conducted a nested case-cohort analysis of mortality to 2 y of age among 103 HIV-infected and 143 HEU children. Breast-milk samples collected at 1 mo postpartum were analyzed for HMO content. Samples were selected to include mothers of all HIV-infected children detected by 6 wk of age, of whom 63 died at

BACKGROUND HIV-infected (HIV-pos) male children/youth showed lower bone mineral density at sexual maturity than HIV-uninfected (HIV-neg) females. It is not known whether complications of HIV disease, including abnormal body fat distribution, contribute to lower bone accrual in male HIV-pos adolescents. METHODS In a cross-sectional study, we evaluated the relationship between body composition (fat and lean mass) and bone mass in HIV-pos and HIV-neg children/youth and determined if it is modified by HIV status and sex. We used generalized estimating equations to simultaneously model the effect of fat/lean mass on multiple bone outcomes, including total body bone mineral density and bone mineral content and spine bone mineral density. We evaluated effect modification by HIV and sex. RESULTS The analysis cohort consisted of 143 HIV-neg and 236 HIV-pos, of whom 55% were black non-Hispanic and 53% were male. Ages ranged from 7 to < 25 years. Half of the children/youth were at Tanner stage 1 and 20% at Tanner 5. Fat mass was more strongly positively correlated with bone mass in HIV-neg than HIV-pos children/youth and these relationships were more evident for total body bone than spine outcomes. Within HIV strata, fat mass and bone were more correlated in female than male children/youth. The relationship between lean mass and bone varied by sex, but not by HIV status. CONCLUSIONS HIV disease diminishes the positive relationship of greater fat mass on bone mass in children/youth. Disruptions in body fat distribution, which are common in HIV disease, may have an impact on bone accretion during pubertal development.

Summary Most infants born to human immunodeficiency virus (HIV)-infected women escape HIV infection. Infants evade infection despite an immature immune system and, in the case of breastfeeding, prolonged repetitive exposure. If infants become infected, the course of their infection and response to treatment differs dramatically depending upon the timing (in utero, intrapartum, or during breastfeeding) and potentially the route of their infection. Perinatally acquired HIV infection occurs during a critical window of immune development. HIV's perturbation of this dynamic process may account for the striking age-dependent differences in HIV disease progression. HIV infection also profoundly disrupts the maternal immune system upon which infants rely for protection and immune instruction. Therefore, it is not surprising that infants who escape HIV infection still suffer adverse effects. In this review, we highlight the unique aspects of pediatric HIV transmission and pathogenesis with a focus on mechanisms by which HIV infection during immune ontogeny may allow discovery of key elements for protection and control from HIV.

Mastitis and abscess in HIV-infected women increase the risk of breastfeeding transmission of HIV. Guidelines encourage women to stop breastfeeding on the affected breast and feed on the contralateral breast. However, impact of breast pathology on breast milk HIV dynamics is unknown.HIV RNA was quantified in 211 breast milk samples collected before, during, and after a clinical mastitis or an abscess diagnosis from 38 HIV-infected women participating in a Zambian breastfeeding study. HIV RNA quantity was compared between affected and unaffected breasts over time using generalized estimating equation models. A sample of 115 women without breast pathology was selected as a control group.In the affected breast, breast milk HIV RNA quantity increased from the pre- to during-pathology period by log(10) 0.45 copies per milliliter [95% confidence interval (CI): 0.16 to 0.74], and after symptom resolution, HIV RNA levels were no different from prepathology levels (log10 -0.04 copies per milliliter 95% CI: -0.33 to 0.25). In the contralateral, unaffected breast, HIV RNA quantity did not significantly increase (log(10) 0.15 copies per milliliter, 95% CI: -0.41 to 0.10). Increase was more marked in women with abscess or with a greater number of mastitis symptoms. HIV RNA was not significantly different between affected and unaffected women, except at the time of diagnosis.Breast milk HIV RNA increased modestly in the affected breast with unilateral mastitis or abscess and returned to prepathology levels with symptom resolution. Contralateral HIV RNA was not affected. Results support guidelines encouraging feeding from the contralateral breast to minimize the risk of HIV transmission associated with unilateral breast pathology.

Background Mother-to-child transmission of human immunodeficiency virus-type 1 (HIV-1) poses a serious health threat in developing countries, and adequate interventions are as yet unrealized. HIV-1 infection is frequently initiated by a single founder viral variant, but the factors that influence particular variant selection are poorly understood. Results Our analysis of 647 full-length HIV-1 subtype C and G viral envelope sequences from 22 mother–infant pairs reveals unique genotypic and phenotypic signatures that depend upon transmission route. Relative to maternal strains, intrauterine HIV transmission selects infant variants that have shorter, less-glycosylated V1 loops that are more resistant to soluble CD4 (sCD4) neutralization. Transmission through breastfeeding selects for variants with fewer potential glycosylation sites in gp41, are more sensitive to the broadly neutralizing antibodies PG9 and PG16, and that bind sCD4 with reduced cooperativity. Furthermore, experiments with Affinofile cells indicate that infant viruses, regardless of transmission route, require increased levels of surface CD4 receptor for productive infection. Conclusions These data provide the first evidence for transmission route-specific selection of HIV-1 variants, potentially informing therapeutic strategies and vaccine designs that can be tailored to specific modes of vertical HIV transmission. Electronic supplementary material The online version of this article (doi:10.1186/s12977-017-0331-z) contains supplementary material, which is available to authorized users.

Physicians caring for infants born to women infected with HIV are likely to be involved in providing guidance to HIV-infected mothers on appropriate infant feeding practices. It is critical that physicians are aware of the HIV transmission risk from human milk and the current recommendations for feeding HIV-exposed infants in the United States. Because the only intervention to completely prevent HIV transmission via human milk is not to breastfeed, in the United States, where clean water and affordable replacement feeding are available, the American Academy of Pediatrics recommends that HIV-infected mothers not breastfeed their infants, regardless of maternal viral load and antiretroviral therapy.

Peak bone mass is achieved in adolescence/early adulthood and is the key determinant of bone mass in adulthood. We evaluated the association of bone mass with human immunodeficiency virus (HIV) infection and antiretroviral therapy (ART) during this critical period among behaviorally HIV-infected young men and seronegative controls.HIV-positive men (N = 199) and HIV-negative controls (N = 53), ages 14-25 years, were studied at 15 Adolescent Trials Network for HIV/AIDS Interventions sites. HIV-positive participants were recruited on the basis of ART status: ART-naive (N = 105) or on a regimen containing a nonnucleoside reverse transcriptase inhibitor (NNRTI; N = 52) or protease inhibitor (PI; N = 42). Bone mineral density (BMD) and content (BMC) and body composition were measured by dual-energy X-ray absorptiometry (DXA). Results were compared across groups by linear modeling. Bone results were adjusted for race, body mass index (BMI), and type of DXA (Hologic/Lunar).The HIV-positive and HIV-negative groups had comparable median age (21 years) and racial/ethnic distribution. Median times since HIV diagnosis were 1.3, 1.9, and 2.2 years in the ART-naive, NNRTI, and PI groups, respectively (P = .01). Total and regional fat were significantly lower in the ART-naive group compared with seronegative controls. Mean BMD and Z scores were generally lower among HIV-positive participants on ART, particularly in the PI group. Average Z scores for the spine were below zero in all 4 groups, including controls.Young men on ART with a relatively recent diagnosis of HIV infection have lower bone mass than controls. Longitudinal studies are required to determine the impact of impaired accrual or actual loss of bone during adolescence on subsequent fracture risk.

Cluster heat maps were used to investigate relationships between body composition, lipid levels, and glucose metabolism in HIV-infected and HIV-uninfected children and young adults using data from a cross-sectional study. Three distinct clusters of participants were identified. One group had lower body fat and higher lipid measures and was mostly HIV infected. The other 2 groups were a mix of HIV-infected and HIV-uninfected participants. Of these, 1 cluster had more participants with higher body fat and insulin resistance, which are risk factors for future cardiovascular disease, and the other had relatively normal measurements on all outcomes.

Background. Early weaning may reduce human immunodeficiency virus (HIV) transmission but may have deleterious consequences for uninfected children. Here we evaluate effects of early weaning on diarrhea morbidity and mortality of uninfected children born to HIV-infected mothers. Methods. HIV-infected women in Lusaka, Zambia, were randomly assigned to breastfeeding for 4 months only or to continue breastfeeding until the mother decided to stop. Replacement and complementary foods were provided and all women were counseled around feeding and hygiene. Diarrhea morbidity and mortality were assessed in 618 HIV-uninfected singletons alive and still breastfeeding at 4 months. Intent-to-treat analyses and comparisons based on actual feeding practices were conducted using regression methods. Results. Between 4 and 6 months, diarrheal episodes were 1.8-fold (95% confidence interval (CI), 1.3‐2.4) higher in the short compared with long breastfeeding group. Associations were stronger based on actual feeding practices and persisted after adjustment for confounding. At older ages, only more severe outcomes, including diarrhea-related hospitalization or death (relative hazard [RH], 3.2, 95% CI, 2.1‐5.1 increase 4‐24 months), were increased among weaned children. Conclusions. Continued breastfeeding is associated with reduced risk of diarrhea-related morbidity and mortality among uninfected children born to HIV-infected mothers in this low-resource setting despite provision of replacement and complementary food and counseling. Clinical Trials Registration. NCT00310726.

Infant feeding policies for HIV-infected women in developing countries differ from policies in developed countries. This article summarizes the epidemiologic data on the risks and benefits of various infant feeding practices for HIV-infected women living in different contexts. Artificial feeding can prevent a large proportion of mother-to-child HIV transmission but also is associated with increases in morbidity and mortality among exposed-uninfected and HIV-infected children. Antiretroviral drugs can be used during lactation and reduce risks of transmission. For most of the developing world, the health and survival benefits of breastfeeding exceed the risks of HIV transmission, especially when antiretroviral interventions are provided.

Most individuals exposed to human immunodeficiency virus (HIV), adults and children alike, do not become infected. Understanding the basis of this protection depends on systematically and comprehensively defining factors that determine the infectiousness of the host and the susceptibility of the recipient. Successful transmission depends on the relative balance between infectiousness and susceptibility, both of which are influenced by biologic, behavioral, and environmental factors. In this review, we discuss the advantages and disadvantages of mother#x2010;to#x2010;child HIV transmission as a model in which to elucidate correlates of immune protection.

BACKGROUND: Early weaning has been recommended to reduce postnatal human immunodeficiency virus (HIV) transmission. We evaluated the safety of stopping breast-feeding at different ages for mortality of uninfected children born to HIV-infected mothers. METHODS: During a trial of early weaning 958 HIV-infected mothers and their infants were recruited and followed up from birth to 24 months postpartum in Lusaka Zambia. One-half of the cohort was randomized to wean abruptly at 4 months and the other half of the cohort was randomized to continue breast-feeding. We examined associations between uninfected child mortality and actual breast-feeding duration and investigated possible confounding and effect modification. RESULTS: The mortality rate among 749 uninfected children was 9.4% by 12 months of age and 13.6% by 24 months of age. Weaning during the interval encouraged by the protocol (4-5 months of age) was associated with a 2.03-fold increased risk of mortality (95% confidence interval [CI] 1.13-3.65) weaning at 6-11 months of age was associated with a 3.54-fold increase (95% CI 1.68-7.46) and weaning at 12-18 months of age was associated with a 4.22-fold increase (95% CI 1.59-11.24). Significant effect modification was detected such that risks associated with weaning were stronger among infants born to mothers with higher CD4(+) cell counts (>350 cells/microL). CONCLUSION: Shortening the normal duration of breast-feeding for uninfected children born to HIV-infected mothers living in low-resource settings is associated with significant increases in mortality extending into the second year of life. Intensive nutritional and counseling interventions reduce but do not eliminate this excess mortality.

Background. The goal of this study was to determine the nature and prevalence of abnormalities in lipids, glucose metabolism, and body composition in behaviorally human immunodeficiency virus (HIV)―infected young women and the relationship of these abnormalities to different classes of antiretroviral therapy regimens. Methods. We conducted a cross-sectional, multicenter study involving 173 behaviorally HIV-infected women aged 14-24 years and 61 HIV-seronegative control subjects. HIV-infected women were categorized as follows: antiretroviral therapy naive (n = 85), receiving a regimen containing a nonnucleoside reverse-transcriptase inhibitor (NNRTI; n = 33), receiving a regimen containing a protease inhibitor (PI; n = 36), or receiving a regimen not containing an NNRTI or a PI (n = 19). Measurements included fasting lipid levels, glucose and insulin levels before and 2 hours after an oral glucose challenge, high-sensitivity C-reactive protein (hsCRP) levels, anthropometry, fat distribution (measured by dual energy X-ray absorptiometry), and antiretroviral therapy and medical histories. Race-adjusted results were compared across groups and within HIV-infected groups. Results. The median age of participants was 20 years. Of HIV-infected subjects, 77% were African American, 35% smoked cigarettes, and 32% reported exercising regularly. More than 40% had a body mass index ≥25. Triglycerides; total, high-density lipoprotein (HDL), and non-HDL cholesterol; and hsCRP levels differed significantly among groups, with higher levels being most common among those receiving antiretroviral therapy. Indices of glucose metabolism did not differ among groups. In general, cholesterol levels, hsCRP levels, and indices of glucose metabolism worsened as body mass index increased. Conclusions. Obesity, dyslipidemia, and inflammation were prominent among HIV-infected adolescent women and, coupled with other risk factors, may accelerate the lifetime risk of cardiovascular disease and other adverse events. These results underscore the need for a multifaceted approach to addressing risk reduction in this population.

OBJECTIVE: Concern for potential adverse effects of antiretroviral (ARV) chemotherapy used to prevent mother-to-child HIV transmission has led the US Public Health Service to recommend long-term follow-up of ARV-exposed children. Nucleoside reverse transcriptase inhibitor ARV agents can inhibit DNA polymerase γ, impairing mitochondrial DNA (mtDNA) synthesis and resulting in depletion or dysfunction.METHODS: We measured the mtDNA content of stored peripheral blood mononuclear cells (PBMCs) of 411 healthy children who were born to HIV-uninfected women and 213 uninfected infants who were born to HIV-infected women with or without in utero and neonatal ARV exposure. Cryopreserved PBMC mtDNA was quantified by using the Primagen Retina Mitox assay.RESULTS: Geometric mean PBMC mtDNA levels were lower at birth in infants who were born to HIV-infected women. Among HIV-exposed children, mtDNA levels were lowest in those who were not exposed to ARVs, higher in those with exposure to zidovudine alone, and higher still in those with combination nucleoside reverse transcriptase inhibitor exposure. A similar pattern was observed in the corresponding women. Levels of mtDNA increased during the first 5 years of life in all HIV-exposed children but achieved normal levels only in those with ARV exposure.CONCLUSIONS: Levels of mtDNA are lower than normal in HIV-exposed children. Contrary to expectation, PBMC mtDNA levels are significantly higher in ARV-exposed, HIV-uninfected infants and their infected mothers compared with ARV-unexposed infants and women. By 5 years, levels of PBMC mtDNA rise to normal concentrations in ARV-exposed children but remain depressed in ARV-unexposed children.

Given the central role that interleukin 15 (IL-15) plays in human immunodeficiency virus (HIV) immunity, we hypothesized that IL-15 in breast milk may protect against postnatal HIV transmission. In a nested case-control study, we compared breast milk IL-15 levels in 22 HIV-infected women who transmitted HIV to their infants to those in 72 nontransmitters. Samples were collected in the first month of life, prior to HIV infection. IL-15 concentrations were associated with a decreased risk of HIV transmission in unadjusted analysis and after adjusting for milk viral load, CD4 cell count, and other cytokines in breast milk. IL-15–mediated immunity may protect against HIV transmission during breast-feeding.

A single dose of tenofovir/emtricitabine (TDF/FTC) during labor significantly reduces peripartum nevirapine-associated viral drug resistance when measured by consensus HIV sequencing. It is unknown whether this effect extends to HIV subpopulations of25-50%. We conducted a randomized trial of single-dose TDF/FTC added to peripartum nevirapine to reduce drug resistance associated with nonnucleoside reverse transcriptase inhibitors (NNRTIs). To detect mutations for NNRTIs comprisingor = 2% of the viral population, we used an oligonucleotide ligation assay (OLA) at codons 103, 106, 181, and 190 of HIV reverse transcriptase. To assess development of drug resistance mutations to our study intervention, OLA was also performed at codons 65 and 184. Among the 328 women included in the 2-week analysis, those receiving TDF/FTC were less likely to have NNRTI resistance by OLA (RR = 0.40, 95% CI = 0.21-0.77). A similar trend was observed among the 315 women included in the 6-week analysis (RR = 0.45, 95% CI = 0.31-0.66). Only two (1%) specimens had detectable K65R by OLA. Both were at 6 weeks postpartum; one was detected in the intervention arm and one in the control arm (p = 0.96). M184V was not detected. The ability of single-dose TDF/FTC to protect against peripartum NVP-induced NNRTI resistance extends to minority populations. This efficacy is achieved without significant selection of TDF- or FTC-resistant viruses.

To compare the distribution of lipid and glucose abnormalities and altered fat distribution among vertically HIV-infected patients and controls.Cross-sectional multicenter study on HIV-infected (HIV-positive) patients, 7-24 years of age, stratified by Tanner stage and protease inhibitor use (protease inhibitor, n = 161 and non- protease inhibitor, n = 79) and seronegative controls (HIV-negative, n = 146).Measurements included fasting lipids, glucose, insulin, 2-h oral glucose tolerance test, dual-energy X-ray absorptiometry, anthropometry, and antiretroviral therapy and medical histories. Multiple linear regression models were used to compare distributions between HIV-positive and HIV-negative groups.Both HIV-positive groups had long exposures to antiretroviral therapy. Protease inhibitor and nonprotease inhibitor groups had similar current CD4 cell count and HIV-1 RNA, but the protease inhibitor group had lower nadir CD4 cell count, higher peak HIV-1 RNA, and more advanced Centers for Disease Control disease stage. In adjusted analyses, both HIV-positive groups had significantly lower mean Z scores for height, weight, BMI, and total and limb fat than the HIV-negative group. Mean triglycerides were significantly higher and high-density lipoprotein cholesterol lower in both HIV-positive groups relative to the HIV-negative group. The protease inhibitor group also had significantly higher mean total, low-density lipoprotein, and non-high density lipoprotein cholesterol. Mean fasting insulin was higher in both HIV-positive groups, and 2-h glucose and insulin were higher in the protease inhibitor group. Ritonavir was associated with increasing dyslipidemia and altered glucose metabolism.In a large group of vertically HIV-infected children and youth with extensive antiretroviral therapy exposure, height, weight, and total and limb fat were lower than in controls. There was a high prevalence of lipid abnormalities among those on protease inhibitors and evidence of developing insulin resistance, factors that may accelerate lifetime risk for cardiovascular disease.

Maternal CD4 count predicts child mortality in HIV-uninfected children born to HIV-infected women.To explore the mediating role of breastfeeding cessation in this relationship, we compared marginal structural models of maternal CD4 count on child death with and without adjustment for breastfeeding.In crude analyses, children of mothers with CD4200 during pregnancy were 3.2 times more likely to die by 18 months (CI 1.3-8.1) as children whose mothers had CD4500. Earlier breastfeeding cessation was also associated with low CD4 (HR 1.8; CI 1.2-2.7). After adjusting for breastfeeding and low birth weight using a marginal structural model, the low CD4 count-child mortality association through 18 months was reduced 17%. The change was overestimated using a traditional Cox proportional hazards model (35% reduction in HR from 3.4 to 2.5).Our analysis suggests that only a small part of the effect of low vs high CD4 count on child mortality through 18 months is mediated through breastfeeding cessation. Our results must be taken into account when deciding whether or not to recommend breastfeeding for infants of HIV-infected mothers.

In developing countries where mother-to-child transmission of HIV through breast-feeding is common little is known about the impact of postpartum transmission on child survival. This study assessed whether children infected postpartum have longer survival from time of infection versus those infected during gestation or delivery. We used a prospective cohort study to analyze data from 213 HIV-infected children enrolled in a breast-feeding intervention trial in Lusaka Zambia (2001 to 2004). Methods: We compared mortality 1 year after HIV infection in children stratified by age of infection: 0 to 3 days (intrauterine (I/U) group) 4 to 40 days (intrapartum/early postpartum [IP/EPP] group) and greater than 40 days (postpartum [PP] group). A total of 61 71 and 81 children were infected in the I/U IP/EPP and PP groups respectively. Children with intrauterine or intrapartum/early postpartum transmission had higher mortality over the first 12 months after infection than children with postpartum transmission (P = 0.001 and P = 0.006 respectively); no differences were detected between children with intrauterine and intrapartum/ early postpartum transmission. Nearly 20% of the I/U and IP/EPP groups died by 100 days after infection whereas nearly 10% of the PP group had died by this time. After adjusting for birth weight maternal CD4 cell count breast-feeding and maternal death children infected postpartum had one quarter the mortality rate (hazard ratio [HR] = 0.27 95% confidence interval [CI]: 0.15 to 0.50) of those infected in utero. Stopping breast-feeding increased mortality in infected children (HR = 3.1 95% CI: 1.8 to 5.3). This study demonstrates a survival benefit among children infected postpartum versus children infected during pregnancy or delivery and a benefit to increased breast-feeding duration among infected children. Testing children for HIV early may provide a means to allow for earlier intervention. (authors)

The human leukocyte antigen HLA-G, highly expressed at the maternal-fetal interface, has a pivotal role in mediating immune tolerance. In this study we investigated the influence of HLA-G 14 bp insertion polymorphism in human immunodeficiency virus (HIV)-1 mother-to-child HIV-1 transmission. The 14 bp insertion polymorphism was analyzed among 99 HIV-1 positive mothers and 329 infants born to HIV-positive mothers in Zambia, among whom vertical transmission status and timing had been determined. HLA-G 14 bp insertion polymorphism was detected using a custom TaqMan single nucleotide polymorphisms (SNPs) genotyping assay. Logistic regression was conducted to examine the associations between HLA-G alleles and the risk of HIV transmission. The 14 bp insertion allele was more frequent in HIV exposed-uninfected (EU) infants than in infected infants, and was associated with reduced risk of both in utero (IU) and intrapartum (IP) HIV transmission, after adjusting for maternal cluster of differentiation 4 (CD4) cell count and plasma viral load. Maternal HLA-G 14 bp insertion genotype and HLA-G concordance between mother and child were not associated with the risk of perinatal HIV transmission. The presence of the 14 bp insertion associates with protection toward IU and IP HIV infection in children from Zambia, suggesting that HLA-G could be involved in the vertical transmission of HIV.

More than 1 million HIV-exposed, uninfected infants are born annually to HIV-positive mothers worldwide. This growing population of infants experiences twice the mortality of HIV-unexposed infants. We found that although there were very few differences seen in the microbiomes of mothers with and without HIV infection, maternal HIV infection was associated with changes in the microbiome of HIV-exposed, uninfected infants. Furthermore, we observed that human breast milk oligosaccharides were associated with bacterial species in the infant microbiome. The disruption of the infant's microbiome associated with maternal HIV infection may contribute to the increased morbidity and mortality of HIV-exposed, uninfected infants.

Accumulating evidence suggests that rates of low bone mass are greater in HIV-infected males than females. Of eleven biomarkers assessed by sex and HIV-status, HIV-infected males had increased levels of soluble CD14 which inversely correlated with bone mineral content and bone mineral density measures, suggesting macrophage activation as a possible mechanism of differential bone loss.

Clinical and subclinical mastitis increase the risk of mother-to-child transmission (MTCT) of HIV-1 through breastfeeding. We hypothesized that a field test for mastitis used for bovine milk, the California Mastitis Test, would detect high cell counts in milk of HIV-infected women. We also investigated whether total milk cell count would positively correlate with viral HIV-1 RNA in the milk of 128 HIV-positive Zambian women. Mean cell counts in each California Mastitis Test scoring category were significantly different (p< 0.01, n = 232). In a subset of 4-month postpartum milk samples tested for HIV-1 RNA, viral RNA levels did not significantly correlate with total cell count (r = 0.166, p = 244). The CMT may serve as a screening tool for mastitis in breastmilk, but total cell count does not correlate with HIV-1 RNA levels. Since both cell-free and cell-associated virus are associated with increased risk of MTCT, investigation of the relationship between total milk cell count and HIV-1 proviral DNA is warranted before a conclusive determination is made regarding use of the CMT as a clinical screening tool to detect cases at high risk for breastmilk transmission.

This study examined the prevalence of primary human immunodeficiency type 1 (HIV-1) drug resistance among recently infected youth in the United States. Of the 55 subjects studied, major mutations conferring HIV drug resistance were present in 10 (18%). Eight (15%) had nonnucleoside reverse-transcriptase inhibitor (NNRTI) mutations, with the majority (6) having the K103N mutation; 2 (4%) had nucleoside reverse-transcriptase inhibitor (NRTI) mutations; and 2 (4%) had protease inhibitor (PI) mutations. Phenotypic drug resistance was present in 12 (22%) subjects: 10 (18%) for NNRTIs, 2 (4%) for NRTIs, and 3 (5.5%) for PIs. The prevalence of primary HIV-1 drug resistance, particularly to NNRTIs, in this group of recently infected youth was high.

Objectives To test whether secretory immunoglobulin A (sIgA) to human immunodeficiency virus (HIV) antigens in breast milk of HIV-positive women is associated with protection against HIV transmission among breast-fed infants. Study design Nested, case-control design in which HIV-specific sIgA was measured in breast milk collected from 90 HIV-positive women enrolled in a study in Lusaka, Zambia. Milk samples were selected to include 26 HIV-positive mothers with infected infants (transmitters) and 64 mothers with uninfected infants (nontransmitters). Results HIV-specific sIgA was detected more often in breast milk of transmitting mothers (76.9%) than in breast milk of nontransmitting mothers (46.9%, P = .009). There were no significant associations between HIV-specific sIgA in breast milk and other maternal factors, including HIV RNA quantities in breast milk, CD4 count, and plasma RNA quantities. Conclusions HIV-specific sIgA in breast milk does not appear to be a protective factor against HIV transmission among breast-fed infants.

HIV and violence are two major public health problems increasingly shown to be connected and relevant to international mental health issues and HIV-related services. Qualitative research is important due to the dearth of literature on this association in developing countries, cultural influences on mental health syndromes and presentations, and the sensitive nature of the topic. The study presented in this paper sought to investigate the mental health issues of an HIV-affected population of women and children in Lusaka, Zambia, through a systematic qualitative study. Two qualitative methods resulted in the identification of three major problems for women: domestic violence (DV), depression-like syndrome, and alcohol abuse; and children: defilement, DV, and behavior problems. DV and sexual abuse were found to be closely linked to HIV and alcohol abuse. This study shows the local perspective of the overlap between violence and HIV. Results are discussed in relation to the need for violence and abuse to be addressed as HIV services are implemented in sub-Saharan Africa.

The effect of abrupt weaning, advocated as a safe transition from exclusive breastfeeding in HIV-exposed children, on the quantity of HIV viral load in breast milk (BMVL) is not known.To determine the effect of abrupt cessation of breastfeeding on serum prolactin, pumped breast milk volume and BMVL obtained 2 weeks after rapid weaning in HIV-infected women.Women enrolled in a prospective study (ZEBS) were randomized to abruptly wean at 20 weeks postpartum or continue exclusive breastfeeding. Breast milk was obtained at 22 weeks by electric breast pump over 10 min from 222 women who had either weaned or continued to breastfeed. Pre- and post-pumping prolactin was measured. BMVL was measured at 20 and 22 weeks in 71 randomly selected women from both groups.Baseline prolactin and breast milk volume was significantly lower among women who had weaned. Detectable (68 versus 42%; P = 0.03) and median BMVL (448 versus50 copies/ml; P = 0.005) was significantly higher among those who had weaned in comparison with those who were still breastfeeding and was significantly higher in the same women after weaning compared with 2 weeks earlier (P = 0.001).BMVL is substantially higher after rapid weaning and this may pose an increased risk of HIV transmission if children resume breastfeeding after a period of cessation. Increases in BMVL with differing degrees of mixed feeding needs to be assessed.

The anti-malarial agent chloroquine has activity against HIV. We compared the effect of chloroquine (n = 18) to an anti-malarial agent without known anti-HIV-activity, sulfadoxine-pyrimethamine (n = 12), on breast milk HIV RNA levels among HIV-infected breastfeeding women in Zambia. After adjusting for CD4 count and plasma viral load, chloroquine was associated with a trend towards lower levels of HIV RNA in breast milk compared with sulfadoxine-pyrimethamine (P = 0.05). Higher breastmilk viral load was also observed among women receiving presumptive treatment for symptomatic malaria compared with asymptomatic controls and among controls reporting fever in the prior week. Further research is needed to determine the potential role of chloroquine in prevention of HIV transmission through breastfeeding.

The objective was to assess the uptake of and adherence to nevirapine to prevent mother-to-child HIV transmission among women of unknown HIV serostatus presenting in labor. We also assessed preliminary efficacy of the approach. Women of unknown HIV serostatus presenting in labor were offered singledose nevirapine in a prospective cohort study. Two additional contemporaneous comparison populations were also studied. Methods: We measured uptake by counting the number of women that accepted enrollment when offered. We measured adherence with cord blood nevirapine assay. We measured preliminary efficacy with HIV DNA polymerase chain reaction of infant blood spots at 4–6 weeks of life. Of 1591 women approached in labor 634 (40%) took up the intervention and received nevirapine of whom 185 (29%) were HIV infected. Of 179 cord blood specimens from HIV-exposed infants that could be evaluated 178 (99.4%) had nevirapine detected. This was higher than the 73 of 98 (74%) adherence rate observed in a comparison cohort in which women self-administered nevirapine before presenting to the labor ward (P 0.001). Of 145 available infant specimens 17 (11.7%) showed evidence of infection at 4–6 weeks compared with 12 of 60 (20%) infants born immediately prior to study commencement whose HIV-infected mothers did not receive nevirapine (P 0.05). Nevirapine without HIV testing upon presentation in labor was accepted by two-fifths of women. Because therapy is directly observed adherence is nearly perfect. Labor ward dosing to enhance nevirapine coverage should be considered as an adjunct to antenatal nevirapine administration for prevention of mother-to-child transmission of HIV. (authors)

Eleven laboratories evaluated the use of dried blood and plasma spots for quantitation of human immunodeficiency virus (HIV) RNA by two commercially available RNA assays, the Roche Amplicor HIV-1 Monitor and the bioMerieux NucliSens HIV-1 QT assays. The recovery of HIV RNA was linear over a dynamic range extending from 4,000 to 500,000 HIV type 1 RNA copies/ml. The Monitor assay appeared to have a broader dynamic range and seemed more sensitive at lower concentrations. However, the NucliSens assay gave more consistent results and could be performed without modification of the kit. HIV RNA was stable in dried whole blood or plasma stored at room temperature or at −70°C for up to 1 year. Dried blood and dried plasma spots can be used as an easy and inexpensive means for the collection and storage of specimens under field conditions for the diagnosis of HIV infection and the monitoring of antiretroviral therapy.

Despite the nutritional and health benefits of breast milk, breast milk can serve as a vector for mother-to-child HIV transmission. Most HIV-infected infants acquire HIV through breastfeeding. Paradoxically, most infants breastfed by HIV-positive women do not become infected. This is potentially attributed to anti-HIV factors in breast milk. Breast milk of HIV-negative women can inhibit HIV infection. However, the HIV-inhibitory activity of breast milk from HIV-positive mothers has not been evaluated. In addition, while significant differences in breast milk composition between transmitting and nontransmitting HIV-positive mothers have been correlated with transmission risk, the HIV-inhibitory activity of their breast milk has not been compared. This knowledge may significantly impact the design of prevention approaches in resource-limited settings that do not deny infants of HIV-positive women the health benefits of breast milk. Here, we utilized bone marrow/liver/thymus humanized mice to evaluate the in vivo HIV-inhibitory activity of breast milk obtained from HIV-positive transmitting and nontransmitting mothers. We also assessed the species specificity and biochemical characteristics of milk's in vivo HIV-inhibitory activity and its ability to inhibit other modes of HIV infection. Our results demonstrate that breast milk of HIV-positive mothers has potent HIV-inhibitory activity and indicate that breast milk can prevent multiple routes of infection. Most importantly, this activity is unique to human milk. Our results also suggest multiple factors in breast milk may contribute to its HIV-inhibitory activity. Collectively, our results support current recommendations that HIV-positive mothers in resource-limited settings exclusively breastfeed in combination with antiretroviral therapy. IMPORTANCE Approximately 240,000 children become infected with HIV annually, the majority via breastfeeding. Despite daily exposure to virus in breast milk, most infants breastfed by HIV-positive women do not acquire HIV. The low risk of breastfeeding-associated HIV transmission is likely due to antiviral factors in breast milk. It is well documented that breast milk of HIV-negative women can inhibit HIV infection. Here, we demonstrate, for the first time, that breast milk of HIV-positive mothers (nontransmitters and transmitters) inhibits HIV transmission. We also demonstrate that breast milk can prevent multiple routes of HIV acquisition and that this activity is unique to human milk. Collectively, our results support current guidelines which recommend that HIV-positive women in resource-limited settings exclusively breastfeed in combination with infant or maternal antiretroviral therapy.

The setpoint of viral RNA concentration (viral load [VL]) during chronic human immunodeficiency virus type 1 (HIV-1) infection reflects a virus-host equilibration closely related to CD8+cytotoxic T-lymphocyte (CTL) responses, which rely heavily on antigen presentation by the human major histocompatibility complex (MHC) (i.e., HLA) class I molecules. Differences in HIV-1 VL among 259 mostly clade C virus-infected individuals (137 females and 122 males) in the Zambia-UAB HIV Research Project (ZUHRP) were associated with several HLA class I alleles and haplotypes. In particular, general linear model analyses revealed lower log10VL among those with HLA allele B*57 (P= 0.002 [without correction]) previously implicated in favorable response and in those with HLA B*39 and A*30-Cw*03 (P= 0.002 to 0.016); the same analyses also demonstrated higher log10VL among individuals with A*02-Cw*16, A*23-B*14, and A*23-Cw*07 (P= 0.010 to 0.033). These HLA effects remained strong (P= 0.0002 to 0.075) after adjustment for age, gender, and duration of infection and persisted across three orders of VL categories (P= 0.001 to 0.084). In contrast, neither B*35 (n= 15) nor B*53 (n= 53) showed a clear disadvantage such as that reported elsewhere for these closely related alleles. Other HLA associations with unusually high (A*68, B*41, B*45, and Cw*16) or low (B*13, Cw*12, and Cw*18) VL were either unstable or reflected their tight linkage respecting disequilibria with other class I variants. The three consistently favorable HLA class I variants retained in multivariable models and in alternative analyses were present in 30.9% of subjects with the lowest (100,000) VL. Clear differential distribution of HLA profiles according to level of viremia suggests important host genetic contribution to the pattern of immune control and escape during HIV-1 infection.

Characteristics unique to paediatric pharmacotherapy should be considered when treating children infected with human immunodeficiency virus (HIV). Processes of growth and development in the paediatric patient can significantly affect drug absorption and disposition. Immature renal function, altered hepatic enzyme activity and differences in drug absorption lead to variations in systemic exposure of antiretrovirals among children. Paediatric patients are also subject to unique circumstances that may prevent adherence to antiretroviral regimens. The pharmacokinetics of nucleoside reverse transcriptase inhibitors differ significantly among preterm infants, full-term infants and older children. Decreased hepatic glucuronidation activity in neonates results in pharmacokinetic differences in zidovudine disposition when compared with older children. Didanosine, stavudine and lamivudine are renally eliminated, thus resulting in differences among young children with immature renal function. Pharmacokinetic data for non-nucleoside reverse transcriptase inhibitors in children are limited. Decreased elimination of nevirapine among neonates has been observed, primarily due to decreased enzymatic activity. Pharmacokinetic differences across age groups have been noted for efavirenz, but no formal assessments have been conducted in children weighing less than 10kg. Protease inhibitors are metabolised by the cytochrome P450 enzyme system, which is not fully developed in younger children. Decreased metabolism can result in elevated plasma concentrations, thereby increasing the chance of toxicity. Unfortunately, few studies exist evaluating the pharmacokinetics of antiretrovirals in children. As a result, dosage selection of antiretrovirals in children often occurs without adequate data. As the life expectancy of HIV-infected children increases, use of antiretrovirals to prevent disease progression also increases. If prevention of treatment failure continues to be the goal of antiretroviral therapy, the pharmacokinetics of antiretrovirals in children need to be assessed early in the drug development process.

We compared a DNA-based assay with a total nucleic acid-based assay for early detection of infant human immunodeficiency virus (HIV) infection. The codetection of DNA and RNA did not result in an overall higher sensitivity compared to that of DNA alone. Discordant results were associated with low levels of HIV DNA, indicating that the sample amount may be critical.

Late-stage HIV-1 disease in humans has been associated with perturbations of the T cell receptor (TCR) Vbeta repertoire. It is not known if the observed loss of certain Vbeta families is attributable directly to HIV-1 infection or whether this is a consequence of multiple opportunistic infections. Putative HIV-1-associated superantigens have been postulated to be the cause of the perturbed TCR Vbeta repertoire and the subsequent CD4+ T cell depletion in HIV-1-infected humans. In this study, we examined the human TCR Vbeta repertoire in SCID-hu mice, housed in a pathogen-free environment and infected with a molecularly cloned virus strain, to ascertain directly the effect of HIV-1 on the human TCR Vbeta repertoire in the absence of other infectious agents. We demonstrate that mock-infected human thymus/liver (Thy/Liv) implants in SCID-hu mice have complete TCR Vbeta repertoires, reflective of a normal human thymus. However, HIV-1-infected implants in SCID-hu mice had depleted TCR Vbeta repertoires, corresponding with thymocyte depletion. These results indicate that HIV-1-specific mechanisms are the cause of the TCR Vbeta repertoire depletion in infected implants. However, these thymocyte depletions were not restricted to specific TCR Vbeta subsets. These results are not consistent with the hypothesis that HIV-1 acts as a superantigen in vivo. The disruption of the TCR Vbeta repertoire in the human Thy/Liv implants of the SCID-hu mice suggests that HIV-1 infection may be influencing T cell development in the thymus, contributing to both the overall CD4+ T cell depletion in AIDS and limited TCR repertoire diversity.

Circulating levels of microbial products such as lipopolysaccharide (LPS) are increased in HIV infection. Microbial translocation promotes obesity, insulin resistance, and dyslipidemia in other settings. We examined data from 178 subjects: an Indiana University (IU) cross-sectional study [N=49 on antiretroviral therapy (ART), N=47 not on ART], and a 24 week prospective study of ART initiation ACTG 5152s (N=82). Pearson correlations were used to describe relationships of plasma LPS levels and soluble CD14 (sCD14), a marker of monocyte activation, with metabolic and body composition measures. HOMA-IR (a measure of insulin resistance) and LPS were correlated for the combined cohorts (r=0.19, p=0.02), particularly in the 5152s ART-naive cohort (r=0.41, p