Audrey L. French

A Compositional Look at the Human Gastrointestinal Microbiome and Immune Activation Parameters in HIV Infected Subjects

HIV progression is characterized by immune activation and microbial translocation. One factor that may be contributing to HIV progression could be a dysbiotic microbiome. We therefore hypothesized that the GI mucosal microbiome is altered in HIV patients and this alteration correlates with immune activation in HIV. 121 specimens were collected from 21 HIV positive and 22 control human subjects during colonoscopy. The composition of the lower gastrointestinal tract mucosal and luminal bacterial microbiome was characterized using 16S rDNA pyrosequencing and was correlated to clinical parameters as well as immune activation and circulating bacterial products in HIV patients on ART. The composition of the HIV microbiome was significantly different than that of controls; it was less diverse in the right colon and terminal ileum, and was characterized by loss of bacterial taxa that are typically considered commensals. In HIV samples, there was a gain of some pathogenic bacterial taxa. This is the first report characterizing the terminal ileal and colonic mucosal microbiome in HIV patients with next generation sequencing. Limitations include use of HIV-infected subjects on HAART therapy.

Causes of death among women with human immunodeficiency virus infection in the era of combination antiretroviral therapy

PURPOSE To examine changes in the causes of death and mortality in women with human immunodeficiency virus (HIV) infection in the era of combination antiretroviral therapy. METHODS Among women with, or at risk of, HIV infection, who were enrolled in a national study from 1994 to 1995, we used an algorithm that classified cause of death as due to acquired immunodeficiency syndrome (AIDS) or non-AIDS causes based on data from death certificates and the CD4 count. Poisson regression models were used to estimate death rates and to determine the risk factors for AIDS and non-AIDS deaths. RESULTS Of 2059 HIV-infected women and 569 who were at risk of HIV infection, 468 (18%) had died by April 2000 (451 HIV-infected and 17 not infected). Causes of death were available for 428 participants (414 HIV-infected and 14 not infected). Among HIV-infected women, deaths were classified as AIDS (n = 294), non-AIDS (n = 91), or indeterminate (n = 29). The non-AIDS causes included liver failure (n = 19), drug overdose (n = 16), non-AIDS malignancies (n = 12), cardiac disease (n = 10), and murder, suicide, or accident (n = 10). All-cause mortality declined an average of 26% per year (P = 0.03) and AIDS-related mortality declined by 39% per year (P = 0.01), whereas non-AIDS-related mortality remained stable (10% average annual decrease, P = 0.73). Factors that were independently associated with non-AIDS-related mortality included depression, history of injection drug use with hepatitis C infection, cigarette smoking, and age. CONCLUSION A substantial minority (20%) of deaths among women with HIV was due to causes other than AIDS. Our data suggest that to decrease mortality further among HIV-infected women, attention must be paid to treatable conditions, such as hepatitis C, depression, and drug and tobacco use.

Comparison of the Diversity of the Vaginal Microbiota in HIV-Infected and HIV-Uninfected Women with or without Bacterial Vaginosis

BACKGROUND Whether human immunodeficiency virus (HIV) infection is associated with a change in the diversity of genital microbiota in women was investigated. METHODS Amplicon length heterogeneity polymerase chain reaction (LH-PCR) analysis and pyrosequencing of the 16S ribosomal RNA gene were used to analyze the diversity of the microbiota in HIV-positive (HIV(+)) and HIV-negative (HIV(-)) women with or without bacterial vaginosis (BV). RESULTS LH-PCR analysis revealed significantly more microbiota diversity in BV-positive (BV(+)) women than in BV-negative (BV(-)) women, but no significant difference was noted between HIV(+) women and HIV(-) women. Pyrosequencing revealed that Lactobacillus organisms constituted a median of 96% of the bacteria in BV(-) women. BV(+) women had a significantly higher number of taxa found at > or =1% of the total genital microbiota (median, 11 taxa). Common taxa in BV(+) women were Prevotella, Megasphaera, Gardnerella, Coriobacterineae, Lachnospira, and Sneathia. There was a trend (P = .07) toward the presence of a higher number of taxa in HIV(+)BV(+) women than in HIV(-)BV(+) women. Propionibacterineae, Citrobacter, and Anaerococcus were the taxa found only in HIV(+) women (P < .05). CONCLUSIONS The present study demonstrated that both LH-PCR analysis and pyrosequencing differentiated microbiota in BV(+) women from that in BV(-) women and that pyrosequencing indicated a trend toward increased diversity in BV(+)HIV(+) women, suggesting that HIV infection is associated with changes in the diversity of genital microbiota.

Soluble Urokinase Receptor and Chronic Kidney Disease

BACKGROUND Relatively high plasma levels of soluble urokinase-type plasminogen activator receptor (suPAR) have been associated with focal segmental glomerulosclerosis and poor clinical outcomes in patients with various conditions. It is unknown whether elevated suPAR levels in patients with normal kidney function are associated with future decline in the estimated glomerular filtration rate (eGFR) and with incident chronic kidney disease. METHODS We measured plasma suPAR levels in 3683 persons enrolled in the Emory Cardiovascular Biobank (mean age, 63 years; 65% men; median suPAR level, 3040 pg per milliliter) and determined renal function at enrollment and at subsequent visits in 2292 persons. The relationship between suPAR levels and the eGFR at baseline, the change in the eGFR over time, and the development of chronic kidney disease (eGFR <60 ml per minute per 1.73 m(2) of body-surface area) were analyzed with the use of linear mixed models and Cox regression after adjustment for demographic and clinical variables. RESULTS A higher suPAR level at baseline was associated with a greater decline in the eGFR during follow-up; the annual change in the eGFR was -0.9 ml per minute per 1.73 m(2) among participants in the lowest quartile of suPAR levels as compared with -4.2 ml per minute per 1.73 m(2) among participants in the highest quartile (P<0.001). The 921 participants with a normal eGFR (≥ 90 ml per minute per 1.73 m(2)) at baseline had the largest suPAR-related decline in the eGFR. In 1335 participants with a baseline eGFR of at least 60 ml per minute per 1.73 m(2), the risk of progression to chronic kidney disease in the highest quartile of suPAR levels was 3.13 times as high (95% confidence interval, 2.11 to 4.65) as that in the lowest quartile. CONCLUSIONS An elevated level of suPAR was independently associated with incident chronic kidney disease and an accelerated decline in the eGFR in the groups studied. (Funded by the Abraham J. and Phyllis Katz Foundation and others.).

Trends in mortality and causes of death among women with HIV in the United States: a 10-year study.

Background:To assess trends in mortality and cause of death for women with HIV, we studied deaths over a 10-year period among participants in the Womens Interagency HIV Study, a representative US cohort. Methods:Deaths were ascertained by National Death Index Plus match, and causes of death determined by death certificate. Results:From 1995 through 2004, 710 of 2792 HIV-infected participants died. During this interval, the standardized mortality ratio fell from a high of 24.7 in 1996 to a plateau with a mean of 10.3 from 2001 to 2004. Over the decade, deaths from non-AIDS causes increased and accounted for the majority of deaths by 2001-2004. The most common non-AIDS causes of death were trauma or overdose, liver disease, cardiovascular disease, and malignancy. Independent predictors of mortality besides HIV-associated variables were depressive symptoms and active hepatitis B or C. Women who were overweight or obese were significantly less likely to die of AIDS than women of normal weight. Conclusions:In the Womens Interagency HIV Study, the death rate has plateaued in recent years. Although HIV-associated factors predicted AIDS and non-AIDS deaths, other treatable conditions predicted mortality. Further gains in reducing mortality among HIV-infected women may require broader access to therapies for depression, viral hepatitis, and HIV itself.

Vitamin D deficiency in HIV-infected and HIV-uninfected women in the United States

Background:Vitamin D deficiency is of increasing concern in HIV-infected persons because of its reported association with a number of negative health outcomes that are common in HIV. We undertook this study to determine the prevalence and predictors of vitamin D deficiency among a nationally representative cohort of middle-aged, ethnically diverse, HIV-infected and HIV-uninfected women enrolled in the Womens Interagency HIV Study (WIHS). Methods:Vitamin D testing was performed by Quest Diagnostics on frozen sera using the liquid chromatography/mass spectroscopy method. Vitamin D deficiency was defined as 25(OH)D ≤20 ng/mL. Comparisons of continuous and categorical characteristics among HIV-infected and HIV-uninfected women were made by Wilcoxon tests and Pearson χ2 tests, respectively. Results:One thousand seven hundred seventy-eight women (1268 HIV positive) were studied. Sixty-three percent had vitamin D deficiency (60% HIV positive vs. 72% HIV negative; P < 0.001). Multivariable predictors of vitamin D deficiency were being African American (adjusted odds ratio 3.02), Hispanic (adjusted odds ratio 1.40), body mass index (adjusted odds ratio 1.43), age (adjusted odds ratio 0.84), HIV positive (adjusted odds ratio 0.76), glomerular filtration rate <90·mL−1·min−1 (adjusted odds ratio 0.94), and WIHS sites Los Angeles (adjusted odds ratio 0.66) and Chicago (adjusted odds ratio 0.63). In the HIV-positive women, multivariate predictors were undetectable HIV RNA (adjusted odds ratio 0.69), CD4 50-200 cells per cubic millimeter (adjusted odds ratio 1.60), CD4 <50 cells per cubic millimeter (adjusted odds ratio 1.94), and recent protease inhibitor use (adjusted odds ratio 0.67). Conclusions:In this study of more than 1700 women in the United States, most women with or without HIV infection had low vitamin D levels and African American women had the highest rates of vitamin D deficiency. An understanding of the role that vitamin D deficiency plays in non-AIDS-related morbidities is planned for investigation in WIHS.

Prevalence of Clinical Symptoms Associated with Highly Active Antiretroviral Therapy in the Women's Interagency HIV Study

BACKGROUND The extended use of antiretroviral drugs among human immunodeficiency virus (HIV)-seropositive individuals underscores the need for a comprehensive evaluation of therapy-associated clinical symptoms. METHODS Beginning in April 2000, 364 HIV-seronegative and 1256 HIV-seropositive women enrolled in a multicenter cohort study reported clinical symptoms that included abdominal pain, diarrhea, anorexia, nausea and/or vomiting, myalgias, fatigue, fever, body fat redistribution, dizziness, headaches, paresthesias, xerostomia, nephrolithiasis, and rash. We examined the prevalence of symptoms with respect to HIV infection and the use of highly active antiretroviral therapy (HAART), using data-correlation models. RESULTS In the 6 months before a study visit, 49% of HIV-seronegative women, 67% of HIV-seropositive women not receiving therapy, and 69% of HIV-seropositive women receiving HAART reported any clinical symptom. The odds ratios (ORs) for reporting any symptom were 1.4 (95% confidence interval [CI], 1.1-1.8) for women who changed HAART regimens and 0.9 (95% CI, 0.7-1.1) for women reporting stable HAART use, compared with those reporting no therapy use. Significant findings (P<.05) for particular symptoms were an increased odds of diarrhea, nausea and/or vomiting, body fat redistribution, myalgias, and paresthesias, when data for women who changed HAART regimens were compared with those for women not receiving therapy. The OR for reporting any symptom was 1.5 (95% CI, 1.2-1.9) for women who switched HAART regimens and 1.6 (95% CI, 1.3-1.9) for women who discontinued HAART, compared with those reporting stable HAART use. CONCLUSIONS Our findings confirm the high prevalence of clinical symptoms among HIV-seropositive women who changed HAART regimens. The high prevalence of symptoms among HIV-seronegative women and HIV-seropositive women not receiving therapy demonstrates that caution should be used when attributing the occurrence of symptoms entirely to HAART.

Regulatory B cell frequency correlates with markers of HIV disease progression and attenuates anti-HIV CD8+ T cell function in vitro

HIV infection is associated with elevated expression of IL‐10 and PD‐L1, contributing to impairment of T cell effector functions. In autoimmunity, tumor immunology, and some viral infections, Bregs modulate T cell function via IL‐10 production. In this study, we tested the hypothesis that during HIV infection, Bregs attenuate CD8+ T cell effector function, contributing to immune dysfunction. We determined that in vitro, TLR2‐, TLR9‐, and CD40L‐costimulated Bregs from HIV− individuals exhibited a high frequency of cells expressing IL‐10 and PD‐L1. Compared with Bregs from HIV− individuals, a significantly higher percentage of Bregs from HIV+ individuals spontaneously expressed IL‐10 (P=0.0218). After in vitro stimulation with HIV peptides, Breg‐depleted PBMCs from HIV+ individuals exhibited a heightened frequency of cytotoxic (CD107a+; P=0.0171) and HIV‐specific CD8+ T cells compared with total PBMCs. Furthermore, Breg depletion led to enhanced proliferation of total CD8+ and CD107a+CD8+ T cells (P=0.0280, and P=0.0102, respectively). In addition, augmented CD8+ T cell effector function in vitro was reflected in a 67% increased clearance of infected CD4+ T cells. The observed Breg suppression of CD8+ T cell proliferation was IL‐10‐dependent. In HIV+ individuals, Breg frequency correlated positively with viral load (r=0.4324; P=0.0095), immune activation (r=0.5978; P=0.0005), and CD8+ T cell exhaustion (CD8+PD‐1+; r=0.5893; P=0.0101). Finally, the frequency of PD‐L1‐expressing Bregs correlated positively with CD8+PD‐1+ T cells (r=0.4791; P=0.0443). Our data indicate that Bregs contribute to HIV‐infection associated immune dysfunction by T cell impairment, via IL‐10 and possibly PD‐L1 expression.

Human α-amylase Present in Lower-Genital-Tract Mucosal Fluid Processes Glycogen to Support Vaginal Colonization by Lactobacillus

Lactobacillus colonization of the lower female genital tract provides protection from the acquisition of sexually transmitted diseases, including human immunodeficiency virus, and from adverse pregnancy outcomes. While glycogen in vaginal epithelium is thought to support Lactobacillus colonization in vivo, many Lactobacillus isolates cannot utilize glycogen in vitro. This study investigated how glycogen could be utilized by vaginal lactobacilli in the genital tract. Several Lactobacillus isolates were confirmed to not grow in glycogen, but did grow in glycogen-breakdown products, including maltose, maltotriose, maltopentaose, maltodextrins, and glycogen treated with salivary α-amylase. A temperature-dependent glycogen-degrading activity was detected in genital fluids that correlated with levels of α-amylase. Treatment of glycogen with genital fluids resulted in production of maltose, maltotriose, and maltotetraose, the major products of α-amylase digestion. These studies show that human α-amylase is present in the female lower genital tract and elucidates how epithelial glycogen can support Lactobacillus colonization in the genital tract.

Total lymphocyte count, hemoglobin, and delayed-type hypersensitivity as predictors of death and AIDS illness in HIV-1-infected women receiving highly active antiretroviral therapy.

Background:Total lymphocyte count (TLC) and hemoglobin level have been suggested as useful and inexpensive parameters to indicate need for HAART in settings in which CD4+ cell counts are unavailable. If delayed-type hypersensitivity (DTH) response predicts clinical response in persons using highly active antiretroviral therapy (HAART), it may also prove useful in resource-poor settings. Objective:To examine whether TLC, hemoglobin, and DTH response observed prior to initiation of HAART predict post-HAART clinical response. Design:Prospective cohort study. Participants:873 women in the Women’s Interagency HIV Study. Measurements:TLC, hemoglobin, CD4+ cell counts, and DTH testing using mumps, candida, and tetanus toxoid antigens, performed within 1 year prior to HAART initiation; death; self-report of initiation of HAART use and AIDS-defining illness (ADI). Results:Three different multivariate analyses were performed: 2 models that excluded CD4+ cell count and assessed TLC at either <850 or <1250 cells/μL, and 1 model that excluded TLC and included CD4+ <200 cells/μL. TLC <850, TLC <1250, CD4+ <200 cells/μL, anergy to DTH testing, hemoglobin <10.6 g/dL, and a pre-HAART report of ADI were each consistently independently associated both with death and with incident ADI. Log likelihood χ2 values suggested similar power among the 3 models in predicting both death and incident ADI. Conclusions:Pre-HAART TLC, hemoglobin level, anergy to DTH testing, and clinical disease each independently predicted morbidity and death after HAART initiation. These findings support the use of TLC to guide decision-making for HAART initiation and suggest that further study of TLC, hemoglobin level, and DTH responses as an indication to provide HAART may be useful in resource-limited settings.