Increasing Prevalence of HIV Pretreatment Drug Resistance in Women But Not Men in Rural Uganda During 2005-2013

The prevalence of HIV pretreatment drug resistance (PDR) is increasing in sub-Saharan Africa. We sought to describe correlates of PDR and evaluate effects of PDR on clinical outcomes in rural Uganda. We analyzed data from the Uganda AIDS Rural Treatment Outcomes study, a cohort of antiretroviral therapy (ART)-naive adults with HIV (2005-2015). We performed resistance testing on pre-ART specimens. We defined PDR as any World Health Organization (WHO) 2009 surveillance drug resistance mutation and classified PDR level using the Stanford algorithm. We fit unadjusted and sex-stratified log binomial regression and Cox proportional hazard models to identify correlates of PDR and the impact of PDR on viral suppression, loss to follow-up (LTFU), and death. We analyzed data from 738 participants (median age 33 years, 69% female). Overall, prevalence of PDR was 3.5% (n = 26), owing mostly to resistance to non-nucleoside reverse transcriptase inhibitors. PDR increased over time in women (1.8% in those enrolling in clinic in 2001-2006, vs. 7.0% in 2007-2013; p = 0.006), but not in men (1.15% vs. 0.72%, p = 0.737). Lower pre-ART log₁₀ HIV RNA was also associated with higher prevalence of PDR. We identified longer time to viral suppression among those with PDR compared with without PDR (0.5 and 0.3 years, respectively, p = 0.023), but there was no significant relationship with mortality or LTFU (p = 0.139). We observed increasing rates of PDR in women in southwestern Uganda. Implications of this trend, particularly to prevention of mother-to-child transmission programs in the region, require attention due to delayed viral suppression among those with PDR.

Elucidating the Burden of HIV in Tissues Using Multiplexed Immunofluorescence and In Situ Hybridization: Methods for the Single-Cell Phenotypic Characterization of Cells Harboring HIV In Situ

Persistent tissue reservoirs of HIV present a major barrier to cure. Defining subsets of infected cells in tissues is a major focus of HIV cure research. Herein, we describe a novel multiplexed in situ hybridization (ISH) (RNAscope) protocol to detect HIV-DNA (vDNA) and HIV-RNA (vRNA) in formalin-fixed paraffin-embedded (FFPE) human tissues in combination with immunofluorescence (IF) phenotyping of the infected cells. We show that multiplexed IF and ISH (mIFISH) is suitable for quantitative assessment of HIV vRNA and vDNA and that multiparameter IF phenotyping allows precise identification of the cellular source of the ISH signal. We also provide semi-quantitative data on the impact of various tissue fixatives on the detectability of vDNA and vRNA with RNAscope technology. Finally, we describe methods to quantitate the ISH signal on whole-slide digital images and validation of the quantitative ISH data with quantitative real-time PCR for vRNA. It is our hope that this approach will provide insight into the biology of HIV tissue reservoirs and to inform strategies aimed at curing HIV.

Detection of HIV-1-specific gastrointestinal tissue resident CD8+ T-cells in chronic infection

Tissue-resident memory (TRM) CD8+ T-cells are non-recirculating, long-lived cells housed in tissues that can confer protection against mucosal pathogens. Human immunodeficiency virus-1 (HIV-1) is a mucosal pathogen and the gastrointestinal tract is an important site of viral pathogenesis and transmission. Thus, CD8+ TRM cells may be an important effector subset for controlling HIV-1 in mucosal tissues. This study sought to determine the abundance, phenotype, and functionality of CD8+ TRM cells in the context of chronic HIV-1 infection. We found that the majority of rectosigmoid CD8+ T-cells were CD69+CD103+S1PR1- and T-betLowEomesoderminNeg, indicative of a tissue-residency phenotype similar to that described in murine models. HIV-1-specific CD8+ TRM responses appeared strongest in individuals naturally controlling HIV-1 infection. Two CD8+ TRM subsets, distinguished by CD103 expression intensity, were identified. CD103Low CD8+ TRM primarily displayed a transitional memory phenotype and contained HIV-1-specific cells and cells expressing high levels of Eomesodermin, whereas CD103High CD8+ TRM primarily displayed an effector memory phenotype and were EomesoderminNeg. These findings suggest a large fraction of CD8+ T-cells housed in the human rectosigmoid mucosa are tissue-resident and that TRM contribute to the anti-HIV-1 immune response. Further exploration of CD8+ TRM will inform development of anti-HIV-1 immune-based therapies and vaccines targeted to the mucosa.

CD8+ T-cell effector molecules are differentially expressed in blood and gastrointestinal mucosa in chronic HIV-1 infection

CD8+ T-cells in human gastrointestinal mucosa exhibit reduced perforin expression and weak cytotoxicity compared to their counterparts in blood. We previously reported that these cells are predominantly T-bet-low and Eomesodermin-negative. Nevertheless, in response to antigenic stimulation these cells degranulate and express cytokines and chemokines. The goal of this study was to elucidate expression patterns of granzymes (Gzm) A, B and K in conjunction with perforin in rectosigmoid CD8+ T-cells during chronic HIV-1 infection and determine whether these patterns vary with disease status. We used flow cytometry to compare intracellular Gzm A, B, K and perforin in resting CD8+ T-cells from blood and rectosigmoid biopsies of HIV-1+ controllers; viremic individuals; virologically suppressed individuals on antiretroviral therapy; and seronegatives. Expression of perforin and GzmB, but not GzmA or GzmK, was reduced in mucosa compared to blood. A large fraction of rectosigmoid CD8+ T-cells did not express granzymes or were single-positive for GzmA. Rectosigmoid CD8+ T-cells appeared skewed towards cytokine production rather than cytotoxicity, with cells expressing multiple cytokines/chemokines lacking perforin and granzyme expression. Percentages of mucosal CD8+ T-cells expressing cytotoxic effectors were higher in HIV-1+ groups, compared to seronegatives. These data support the interpretation that perforin and granzymes are differentially regulated, and display distinct expression patterns in blood and rectosigmoid T-cells. These findings also reinforce our previous work, suggesting that rectosigmoid CD8+ T-cells are programmed for cytokine polyfunctionality rather than cytotoxicity.

A20 upregulation during treated HIV disease is associated with intestinal epithelial cell recovery and function

TRIAL REGISTRATION

ClinicalTrials.gov Clinical Trial NCT00594880.

Association of Retinal Vascular Caliber and Age-Related Macular Degeneration in Patients With the Acquired Immunodeficiency Syndrome

Purpose

To evaluate the relationship between retinal vascular caliber and AMD in patients with AIDS.

Methods

Participants enrolled in the Longitudinal Study of the Ocular Complications of AIDS had retinal photographs taken at enrollment. Retinal vascular caliber (central retinal artery equivalent [CRAE] and central retinal vein equivalent [CRVE]) and intermediate-stage AMD were determined from these retinal photographs. Photographs were evaluated by graders at a centralized reading center, using the Age-Related Eye Disease Study grading system for AMD and semiautomated techniques for evaluating retinal vascular caliber.

Results

Of the 1171 participants evaluated, 110 (9.4%) had AMD and 1061 (90.6%) did not. Compared with participants without AMD, participants with AMD had larger mean CRAEs (151 ± 16 μm versus 147 ± 16 μm; P = 0.009) and mean CRVEs (228 ± 24 μm versus 223 ± 25 μm; P = 0.02). The unadjusted differences were: CRAE, 4.3 μm (95% confidence interval [CI] 1.1-7.5; P = 0.009) and CRVE, 5.5 μm (95% CI 0.7-10.3; P = 0.02). After adjustment for age, race/ethnicity, sex, human immunodeficiency syndrome (HIV) transmission category, smoking, enrollment and nadir CD4+ T cells, and enrollment and maximum HIV load, the differences between patients with and without AMD were as follows: CRAE, 5.4 μm (95% CI 2.3-8.5; P = 0.001) and CRVE, 6.0 μm (95% CI 1.4-10.6; P = 0.01).

Conclusions

In patients with AIDS, AMD is associated with greater retinal arteriolar and venular calibers, suggesting a role for shared pathogenic mechanisms, such as persistent systemic inflammation.

Can Biomarkers Advance HIV Research and Care in the Antiretroviral Therapy Era?

Despite achieving human immunodeficiency virus type 1 (HIV-1) RNA suppression below levels of detection and, for most, improved CD4+ T-cell counts, those aging with HIV experience excess low-level inflammation, hypercoagulability, and immune dysfunction (chronic inflammation), compared with demographically and behaviorally similar uninfected individuals. A host of biomarkers that are linked to chronic inflammation are also associated with HIV-associated non-AIDS-defining events, including cardiovascular disease, many forms of cancer, liver disease, renal disease, neurocognitive decline, and osteoporosis. Furthermore, chronic HIV infection may interact with long-term treatment toxicity and weight gain after ART initiation. These observations suggest that future biomarker-guided discovery and treatment may require attention to multiple biomarkers and, possibly, weighted indices. We are clinical trialists, epidemiologists, pragmatic trialists, and translational scientists. Together, we offer an operational definition of a biomarker and consider how biomarkers might facilitate progress along the translational pathway from therapeutic discovery to intervention trials and clinical management among people aging with or without HIV infection.

Differential Expression of CD8+ T Cell Cytotoxic Effector Molecules in Blood and Gastrointestinal Mucosa in HIV-1 Infection

We previously reported that CD8⁺ T cells in human gastrointestinal mucosa exhibit reduced perforin expression and weak or impaired cytotoxic capacity compared with their counterparts in blood. Nevertheless, these cells degranulate and express cytokines and chemokines in response to cognate Ag. In addition to weak expression of perforin, earlier studies suggested differential regulation of perforin and granzymes (Gzms), with GzmA and B expressed by significantly higher percentages of mucosal CD8⁺ T cells than perforin. However, this topic has not been fully explored. The goal of this study was to elucidate the expression and coexpression patterns of GzmA, B, and K in conjunction with perforin in rectosigmoid CD8⁺ T cells during HIV-1 infection. We found that expression of both perforin and GzmB, but not GzmA or GzmK, was reduced in mucosa compared with blood. A large fraction of rectosigmoid CD8⁺ T cells either did not express Gzms or were single-positive for GzmA. Rectosigmoid CD8⁺ T cells appeared skewed toward cytokine production rather than cytotoxic responses, with cells expressing multiple cytokines and chemokines generally lacking in perforin and Gzm expression. These data support the interpretation that perforin and Gzms are differentially regulated, and display distinct expression patterns in blood and rectosigmoid T cells. These studies may help inform the development of strategies to combat HIV-1 and other mucosal pathogens.

Inflammation investigated as a source of pharmacokinetic variability of atazanavir in AIDS Clinical Trials Group protocol A5224s

BACKGROUND

Inflammation is associated with the downregulation of drug metabolizing enzymes and transporters. Thus, we investigated the chronic inflammatory state associated with HIV infection as a source of pharmacokinetic variability of atazanavir. We also explored the association of total bilirubin concentrations with markers of inflammation and endothelial activation.

METHODS

Apparent oral clearance (CL/F) of atazanavir was estimated from plasma samples collected from participants in AIDS Clinical Trials Group Study A5202. Several inflammatory and endothelial activation biomarkers were measured at baseline and weeks 24 and 96 as part of metabolic substudy A5224s: high-sensitivity C-reactive protein (hsCRP), interleukin-6, tumour necrosis factor-α and its soluble receptors, soluble vascular cellular and intracellular adhesion molecules and total bilirubin. Statistical analysis was performed by a matrix of correlation coefficients between atazanavir CL/F and biomarker concentrations measured at week 24. The correlation between atazanavir clearance and percentage change in bilirubin from baseline to weeks 24 and 96, and between biomarkers and bilirubin concentrations at each week were also evaluated.

RESULTS

Among 107 participants, there were no significant correlations observed between atazanavir CL/F and inflammatory and endothelial activation biomarkers measured at week 24 (P≥0.24). As expected, bilirubin increased with increasing exposure to atazanavir (rho=-0.25, P=0.01). Bilirubin concentrations were inversely correlated (P<0.01) with each of the biomarkers except hsCRP.

CONCLUSIONS

Atazanavir CL/F did not correlate with the inflammatory biomarkers changes. Inflammatory-mediated inhibition of cytochrome P450 3A may have been attenuated due to atazanavir-associated increases of bilirubin, which has known anti-inflammatory properties.

An Optimized and Validated Method for Isolation and Characterization of Lymphocytes from HIV+ Human Gut Biopsies

The gastrointestinal (GI) tract harbors most of the body's immune cells and is also a major HIV reservoir in ART-treated patients. To achieve a cure, most HIV-infected cells must be identified and eliminated. While obtaining gut biopsies is a relatively noninvasive method of sampling relevant tissue for monitoring HIV activity, immune cell isolation from these limited tissue samples has proven to be challenging. Enzymatic tissue digestion is required for maximal immune cell isolation from gut biopsies. However, these enzymatic digestions can also be detrimental for preservation of cellular surface markers that are required for accurate identification of various subsets of leukocytes. In this study, we describe an optimized protocol for isolation of lymphocytes from human gut biopsies. We also discuss our validation results, which show that compared with several other collagenase preparations, the use of CSLPA maintains high lymphocyte recovery while preserving the integrity of most cellular surface antigens that we tested. Importantly, chemokine receptors that are used to characterize various subsets of T cells, which are notorious for being digested during a typical enzymatic tissue digestion, are highly preserved using this protocol.

Brief Report: Should Abacavir Be a First-Line Alternative for Adults With HIV in Sub-Saharan Africa?

Despite a poor toxicity profile, zidovudine supersedes abacavir (ABC) as an alternative first-line agent in most international treatment guidelines because of concerns about HLA-B*57:01-related ABC-hypersensitivity. We detected one case of HLA-B*57:01 carriage among 513 HIV-infected individuals in Uganda, which, in combination with previous reports, supports the safety of ABC in the region.

Higher Body Mass Index Is Associated With Greater Proportions of Effector CD8+ T Cells Expressing CD57 in Women Living With HIV

BACKGROUND

A low proportion of CD28CD8 T cells that express CD57 is associated with increased mortality in HIV infection. The effect of increasing body mass index (BMI) changes in the proportion of CD57CD28CD8 T cells among HIV-infected individuals on antiretroviral therapy is unknown.

SETTING

In a US cohort of HIV-infected women, we evaluated associations of BMI and waist circumference with 3 distinct CD8 T cell phenotypes: % CD28CD57CD8 T cells, % CD57 of CD28CD8 T cells, and % CD28 of all CD8 T cells.

METHODS

Multivariable linear regression analysis was used to estimate beta coefficients for each of 3 T-cell phenotypes. Covariates included HIV parameters (current and nadir CD4, current viral load), demographics (age, race, income, and study site), and lifestyle (tobacco and alcohol use) factors.

RESULTS

Of 225 participants, the median age was 46 years and 50% were obese (BMI >30 m/kg). Greater BMI and waist circumference were both associated with higher % CD28CD57CD8 T cells and % CD57 of all CD28CD8 T cells in multivariable analysis, including adjustment for HIV viral load (all P < 0.05). The association between greater BMI and the overall proportion of CD28 CD8 cells in fully adjusted models (0.078, 95% confidence interval: -0.053 to 0.209) was not significant.

CONCLUSIONS

In this analysis, greater BMI and waist circumference are associated with greater expression of CD57 on CD28CD8 T cells and a greater proportion of CD57CD28 CD8 T cells. These findings may indicate that increasing BMI is immunologically protective in HIV-infected women. Future research is needed to understand the prognostic importance of these associations on clinical outcomes.

A Randomized Controlled Trial of Lisinopril to Decrease Lymphoid Fibrosis in Antiretroviral-Treated, HIV-infected Individuals

BACKGROUND

In HIV infection, lymphoid tissue is disrupted by fibrosis. Angiotensin converting enzyme inhibitors have anti-fibrotic properties. We completed a pilot study to assess whether the addition of lisinopril to antiretroviral therapy (ART) reverses fibrosis of gut tissue, and whether this leads to reduction of HIV RNA and DNA levels.

METHODS

Thirty HIV-infected individuals on ART were randomized to lisinopril at 20mg daily or matching placebo for 24 weeks. All participants underwent rectal biopsies prior to starting the study drug and at 22 weeks, and there were regular blood draws. The primary end point was the change in HIV RNA and DNA levels in rectal tissue. Secondary outcomes included the change in 1) HIV levels in blood; 2) Gag-specific T-cell responses; 3) levels of T-cell activation; and 4) collagen deposition.

RESULTS

The addition of lisinopril did not have a significant effect on the levels of HIV RNA or DNA in gut tissue or blood, Gag-specific responses, or levels of T-cell activation. Lisinopril also did not have a significant impact on lymphoid fibrosis in the rectum, as assessed by quantitative histology or heavy water labeling.

CONCLUSIONS

Treatment with lisinopril for 24 weeks in HIV-infected adults did not have an effect on lymphoid fibrosis, immune activation, or gut tissue viral reservoirs. Further study is needed to see if other anti-fibrotic agents may be useful in reversing lymphoid fibrosis and reducing HIV levels.

Disease drivers of aging

It has long been known that aging, at both the cellular and organismal levels, contributes to the development and progression of the pathology of many chronic diseases. However, much less research has examined the inverse relationship-the contribution of chronic diseases and their treatments to the progression of aging-related phenotypes. Here, we discuss the impact of three chronic diseases (cancer, HIV/AIDS, and diabetes) and their treatments on aging, putative mechanisms by which these effects are mediated, and the open questions and future research directions required to understand the relationships between these diseases and aging.

Predominance of weakly cytotoxic, T-betLowEomesNeg CD8+ T-cells in human gastrointestinal mucosa: implications for HIV infection

The gastrointestinal mucosa is an important site of HIV acquisition, viral replication, and pathogenesis. Immune cells in mucosal tissues frequently differ in phenotype and function from their non-mucosal counterparts. Although perforin-mediated cytotoxicity as measured in blood is a recognized correlate of HIV immune control, its role in gastrointestinal tissues is unknown. We sought to elucidate the cytotoxic features of rectal mucosal CD8⁺ T-cells in HIV infected and uninfected subjects. Perforin expression and lytic capacity were significantly reduced in rectal CD8⁺ T-cells compared with their blood counterparts, regardless of HIV clinical status; granzyme B (GrzB) was reduced to a lesser extent. Mucosal perforin and GrzB expression were higher in participants not on antiretroviral therapy compared with those on therapy and controls. Reduction in perforin and GrzB was not explained by differences in memory/effector subsets. Expression of T-bet and Eomesodermin was significantly lower in gut CD8⁺ T-cells compared with blood, and in vitro neutralization of TGF-β partially restored perforin expression in gut CD8⁺ T-cells. These findings suggest that rectal CD8⁺ T-cells are primarily non-cytotoxic, and phenotypically shaped by the tissue microenvironment. Further elucidation of rectal immune responses to HIV will inform the development of vaccines and immunotherapies targeted to mucosal tissues.

Early and Delayed Antiretroviral Therapy Results in Comparable Reductions in CD8+ T Cell Exhaustion Marker Expression

In untreated HIV infection, CD8+ T cell exhaustion (i.e., decreased proliferative and effector capacity) is associated with high levels of expression of coinhibitory receptors, including PD-1, T cell immunoreceptor with Ig and ITIM domains (TIGIT), CD160, and 2B4. This is evident for both HIV-specific and non-HIV-specific CD8+ T cells. Antiretroviral therapy (ART) initiated during chronic infection decreases but may not completely normalize the expression of such "exhaustion markers." Compared to initiation of ART later in the course of disease, initiation soon after infection reduces some parameters of chronic inflammation and adaptive immune dysfunction. However, it is not known if Early ART (e.g., initiated within the first 6 months after HIV infection) versus Delayed ART (e.g., initiated during chronic infection) preferentially reduces expression of exhaustion markers. We evaluated exhaustion marker expression on subsets of circulating effector and memory CD8+ T cells at longitudinal pre- and post-ART (2 and 5 years on ART) time points from n = 19 (Early ART) and n = 23 (Delayed ART) individuals. Before ART, TIGIT and CD160 were expressed on a statistically significantly higher proportion of effector and transitional memory cells from individuals in the Delayed ART group: the timing of ART initiation, however, did not consistently affect the expression of the exhaustion markers once viral suppression was achieved. Understanding which factors do and do not regulate aspects of CD8+ T cell exhaustion, including the expression of exhaustion markers, is critical to inform the rational design of CD8+ T cell-based therapies to treat HIV, for which CD8+ T cell exhaustion remains an important barrier to efficacy.

Incidence of Intermediate-stage Age-related Macular Degeneration in Patients With Acquired Immunodeficiency Syndrome

PURPOSE

To evaluate the incidence of intermediate-stage age-related macular degeneration (AMD) in patients with acquired immunodeficiency syndrome (AIDS).

DESIGN

Cohort study.

METHODS

Patients enrolled in the Longitudinal Study of the Ocular Complications of AIDS (LSOCA) underwent 5- and 10-year follow-up retinal photographs. Intermediate-stage AMD (AREDS stage 3) was determined from these photographs by graders at a centralized Reading Center, using the Age-Related Eye Disease Study-2 grading system. The incidence of AMD in LSOCA was compared with that in the Multi-Ethnic Study of Atherosclerosis (MESA), a Human Immunodeficiency Virus (HIV)-uninfected cohort, which used a similar photographic methodology.

RESULTS

The incidence of AMD in LSOCA was 0.65/100 person-years (PY). In a multivariate analysis the only significant risk factor for AMD in LSOCA was smoking; the relative risk vs never-smokers was 3.4 for former smokers (95% confidence interval [CI] 1.3, 9.5; P = .02) and 3.3 for current smokers (95% CI 1.1, 9.7; P = .03). Compared with the MESA cohort, the race/ethnicity- and sex-adjusted risk of AMD in LSOCA was 1.75 (95% CI 1.16, 2.64; P = .008), despite the fact that the mean age of the MESA cohort was 17 years greater than the LSOCA cohort (61 ± 9 years vs 44 ± 8 years).

CONCLUSIONS

Patients with AIDS have a 1.75-fold increased race- and sex-adjusted incidence of intermediate-stage AMD compared with that found in an HIV-uninfected cohort. This increased incidence is consistent with the increased incidence of other age-related diseases in antiretroviral-treated, immune-restored, HIV-infected persons when compared with HIV-uninfected persons.

Human Immunodeficiency Virus Persistence and T-Cell Activation in Blood, Rectal, and Lymph Node Tissue in Human Immunodeficiency Virus-Infected Individuals Receiving Suppressive Antiretroviral Therapy

Background

Immune activation and inflammation remain elevated in human immunodeficiency virus (HIV)-infected individuals receiving antiretroviral therapy (ART) and may contribute to HIV persistence.

Methods

Using flow cytometry expression of CD38, HLA-DR and PD-1 were measured in blood (n = 48), lymph node (LN; n = 9), and rectal tissue (n = 17) from virally suppressed individuals. Total and integrated HIV DNA, 2-LTR circles, and cell-associated unspliced HIV RNA were quantified.

Results

CD4+ T cells from rectal tissue had a higher frequency of integrated HIV DNA compared with blood (4.26 fold-change in DNA; 95% confidence interval [CI] = 2.61-7.00; P < .001) and LN (2.32 fold-change in DNA; 95% CI = 1.22-4.41; P = .01). In rectal tissue, there were positive associations between integrated HIV DNA with PD-1+ CD4+ T-cells (1.44 fold-change in integrated HIV DNA per 10-unit increase in PD-1+ CD4+ T cells; 95% CI = 1.01-2.05; P = .045) and CD38+HLA-DR+ CD8+ T cells (1.40 fold-change in integrated HIV DNA per 1-unit increase in CD38+HLA-DR+ CD8+ T cells; 95% CI = 1.05-1.86; P = .02). Both associations were independent of current and nadir CD4+ T-cell counts.

Conclusions

During ART, rectal tissue is an important reservoir for HIV persistence with a high frequency of activated CD4+ and CD8+ T cells. PD-1 may represent a marker of HIV persistence in rectal tissue.

Circulating LOXL2 Levels Reflect Severity of Intestinal Fibrosis and GALT CD4+ T Lymphocyte Depletion in Treated HIV Infection

BACKGROUND

Incomplete immune reconstitution may occur despite successful antiretroviral therapy (ART). Gut-associated lymphoid tissue (GALT) fibrosis may contribute via local CD4+ T lymphocyte depletion, intestinal barrier disruption, microbial translocation, and immune activation.

METHODS

In a cross-sectional analysis, we measured circulating fibrosis biomarker levels on cryopreserved plasma from adult HIV-infected (HIV+) SCOPE study participants on suppressive ART who also had fibrosis quantification on recto-sigmoid biopsies. Relationships among biomarker levels, clinical and demographic variables, GALT lymphoid aggregate (LA) collagen deposition, and LA CD4+ T lymphocyte density were analyzed using simple regression. Biomarker levels were also compared to levels in HIV+ viremic SCOPE participants and a convenience sample of HIV-uninfected (HIV-) samples.

RESULTS

HIV+ aviremic participants (n = 39) were 92% male and 41% non-white, with median age 48 years, CD4+ T lymphocyte count 277 cells/mm3, and 17 years since HIV diagnosis. Most biomarkers were lower in HIV- (n = 36) vs HIV+ aviremic individuals, although CXCL4 levels were higher. HIV+ viremic individuals (N = 18) had higher median TGF-β3, CIC-C1Q, and TIMP-1 (P < 0.05) and lower LOXL2 levels (P = 0.08) than HIV+ aviremic individuals. Only higher LOXL2 levels correlated with more GALT collagen deposition (R = 0.44, P= 0.008) and lower LA CD4+ T lymphocyte density (R = -0.32, P = 0.05) among aviremic individuals.

CONCLUSIONS

Circulating LOXL2 levels may be a noninvasive measure of intestinal fibrosis and GALT CD4+ T lymphocyte depletion in treated HIV infection. LOXL2 crosslinks elastin and collagen, and elevated LOXL2 levels occur in pathologic states, making LOXL2 inhibition a potential interventional target for intestinal fibrosis and its sequelae.

Duration of Viral Suppression and Risk of Rebound Viremia with First-Line Antiretroviral Therapy in Rural Uganda

Little is known about associations between viral suppression, adherence, and duration of prior viral suppression in sub-Saharan Africa. Study participants were from the UARTO study in Mbarara, Uganda. We fit regression models to characterize relationships between average adherence, treatment interruptions, and rebound viremia (>400 copies/mL) following a previously undetectable result. Our goal was to understand the impact of prior viral suppression on these relationships. 396 participants contributed 2864 quarterly visits. Restricted to periods with average adherence <50 %, each 10 % increase in adherence reduced the odds of rebound viremia by 74 % [adjusted odds ratio (AOR) = 0.26, P = 0.002] and 29 % (AOR = 0.71, P = 0.057) during the first 12 months of suppression and beyond 12 months respectively, interaction term P = 0.018. Among periods with adherence ≥50 %, the risk of rebound viremia decreased with increasing adherence during the first 12 months of viral suppression (AOR = 0.73 for each 10 % increase, P = 0.001), but not thereafter (AOR = 1.09, P = 0.67), interaction term P = 0.027. In contrast, 72-h interruptions, were associated with increased rebound viremia during the first 12 months (AOR = 1.30, P = 0.009) and after (AOR = 1.39, P = 0.005), interaction term P = 0.69. Completing 12 months of viral suppression decreases the impact of average adherence, but not prolonged treatment interruptions, on risk of rebound viremia.

Limited engraftment of donor microbiome via one-time fecal microbial transplantation in treated HIV-infected individuals

Many HIV-infected individuals on antiretroviral therapy (ART) exhibit persistent systemic inflammation, which predicts morbidity and mortality. ART-treated subjects concurrently exhibit marked compositional alterations in the gut bacterial microbiota and the degree of dysbiosis correlates with systemic inflammation. Whether interventions to modulate the microbiome can affect systemic inflammation is unknown. An open-label fecal microbial transplantation (FMT) was delivered by colonoscopy to asymptomatic HIV-infected ART-suppressed individuals without antibiotic pre-treatment. Stool was assessed before and after FMT for engraftment of donor microbes, and peripheral blood was assayed for immune activation biomarkers. Six participants received FMT and 2 participants served as controls. No serious adverse effects occurred during 24 weeks of follow-up. At baseline, HIV-infected individuals exhibited microbiota profiles distinct from uninfected donors. During the 8 weeks post-FMT, recipients demonstrated partial engraftment of the donor microbiome (P < 0.05). Recipient microbiota remained significantly distant from donors, unlike that observed following FMT for treatment of C. difficile infection. Systemic inflammatory markers showed no significant change post-FMT. FMT was well-tolerated in ART-treated, HIV-infected individuals. Engraftment was detectable but modest, and appeared to be limited to specific bacterial taxa. Whether antibiotic conditioning can enhance engraftment and the capacity of microbiota to modulate inflammation remains to be investigated.

Cooking fuel and respiratory symptoms among people living with HIV in rural Uganda

Household air pollution (HAP) and chronic HIV infection are each associated with significant respiratory morbidity. Little is known about relationships between HAP and respiratory symptoms among people living with HIV. The objective of this study was to investigate the relationship between cooking fuel type and chronic respiratory symptoms in study participants from the Uganda AIDS Rural Treatment Outcomes Study.

Study participants were enrolled at the time of antiretroviral therapy initiation and seen quarterly from 2005 to 2014 for health-focused questionnaires, CD4 count and HIV viral load. We used multivariable logistic regression and generalised estimating equations, with each study visit as a unit of observation, to investigate relationships between cooking fuel type and chronic respiratory symptoms.

We observed an association between cooking with firewood (versus charcoal) and chronic cough among HIV-infected females in rural Uganda (adjusted OR 1.41, 95% CI 1.00–1.99; p=0.047). We did not observe an association between cooking fuel type and respiratory symptoms among males (adjusted OR 0.88, 95% CI 0.47–1.63; p=0.658).

Associations between cooking fuel and chronic cough in this HIV-infected cohort may be influenced by sex-based roles in meal preparation. This study raises important questions about relationships between household air pollution, HIV infection and respiratory morbidity.

This study raises important questions about relationships between air pollution, HIV and respiratory morbidityhttp://ow.ly/zjsJ30arkI0

Immunologic Biomarkers, Morbidity, and Mortality in Treated HIV Infection

Despite marked improvements in the modern treatment era, human immunodeficiency virus (HIV)-infected individuals, particularly those who initiated antiretroviral therapy (ART) at advanced disease stages, continue to have increased age-related morbidity and mortality, compared with the general population. Immune activation and inflammation persist despite suppressive ART and predict many of these morbidities. The goal of this review is to examine the evidence suggesting a link between the persistent inflammatory state and morbidity and mortality in this setting, to describe the impact of early ART initiation on these factors, and to highlight important unanswered questions for the field. We also advance a hypothesis to explain why some morbidities-and their root inflammatory drivers-may be prevented more than others by early ART initiation.

Functionality of tissue-resident CD8+ T-cells in the human gastrointestinal tract during chronic HIV-1 infection

The gastrointestinal tract (GIT) is an important site of HIV transmission and pathogenesis. Preventing or curing HIV infection will likely entail maintenance of protective anti-HIV immune responses in the GIT. Tissue resident memory T-cells (TRM) are long-lived, non-recirculating memory T-cells localized in tissues including the GIT. Positioned near sites of infection, TRM have protective efficacy against several pathogens. The precise role CD8+ TRM in HIV infection is not known. Blood and GIT CD8+ TRM cells from HIV+ and HIV- adults were identified by flow cytrometry using CD45RO, CD69, CD103, S1PR1, T-bet, and Eomesodermin (Eomes). Functionality was assessed in a 6-hour ex vivo stimulation assay. Cells were stimulated with DMSO, Gag, or Staphylococcal Enterotoxin B, and stained for CD107a, IFNγ, Mip-1β, TNFα, and IL-2. The frequency of CD103+CD69+S1PR1− CD8+ T-cells was significantly greater (P=0.005) in gut compared to blood (medians 54.8% and 0.10% respectively), indicative of tissue residency. CD45RO+ cells in this subset were classified as TRM. Consistent with murine studies, CD8+TRM were mainly T-betLowEomesNeg; however a population of EomesHigh CD8+ TRM emerged in HIV+ individuals not on antiretroviral therapy. Although polyfunctional Gag-specific CD8+ TRM responses (CD107a+, IFNγ+, Mip-1β+) appeared strongest in participants who control HIV without therapy (“controllers”), they constituted a smaller proportion of the total rectal Gag-specific CD8+ T-cell response compared to viremic participants not on ART (approximately 15% and 29% respectively). In summary, a large subset of CD8+ T-cells in rectal mucosa are TRM and likely play an important role in HIV-1 containment.