Chronic immune activation and accelerated immune aging among HIV-infected adults receiving suppressive antiretroviral therapy for at least 12 years in an African cohort.

Background: HIV-associated alterations innate and adaptive immune cell compartments are reminiscent of the process of immune aging. Objectives: We described immune aging phenotypes among ART-treated HIV-infected adults relative to age-matched HIV-negative counterparts. Methods: In a cross-sectional comparative study of HIV-infected adults with CD4≥500 cells/µl after at least 12 years of suppressive ART and age-and-gender-matched HIV-negative individuals, immune activation and immune aging phenotypes were measured, using multi-color flowcytometry. Results: ART-treated HIV-infected individuals had higher body mass index (P = 0.004), waist-hip circumference (P = 0.041), hip circumference (P < 0.001), and diastolic blood pressure (P = 0.012) and immune activation (CD4+CD38+HLADR+; median 4.15,IQR(1.030,14.6)] relative to the HIV-negative age-matched individuals [median 3.14,IQR(1.030, 6.68)]; P=0.0034. Immune aging markers [CD4+CD57+T-cells; median 13.00 IQR (0.45,64.1)] were higher among HIV-infected ART-treated adults<50 years relative to HIV-negative<50 years[median 8.020,IQR(0.004,21.2)]; P=0.0010. Naïve CD4 T-cells, Central memory CD4 T-cells, Terminal Effector Memory T cells (TEMRA: CD27-CD45RA + CCR7-) and immune senescence CD4/CD8+CD28-/CD57+ T-cells were similar among ART-treated HIV-infected individuals<45 years relative to 60 years-and-older HIV-negative counterparts≥; p = 0.0932, p = 0.05357, p = 0.0950 and p = 0.5714 respectively. Conclusion: ART-treated adults are immunologically two decades older than their HIV-negative counterparts. Accelerated immune aging among individuals aging with HIV underscores the need for an HIV cure to avert the unprecedented complications of accelerated immune senescence and the associated NCD risk in African settings with protracted exposure to endemic co-infections.

Towards access for all: 1st Working Group Report for the Global Gene Therapy Initiative (GGTI).

The gene and cell therapy field saw its first approved treatments in Europe in 2012 and the United States in 2017 and is projected to be at least a $10B USD industry by 2025. Despite this success, a massive gap exists between the companies, clinics, and researchers developing these therapeutic approaches, and their availability to the patients who need them. The unacceptable reality is a geographic exclusion of low-and middle-income countries (LMIC) in gene therapy development and ultimately the provision of gene therapies to patients in LMIC. This is particularly relevant for gene therapies to treat human immunodeficiency virus infection and hemoglobinopathies, global health crises impacting tens of millions of people primarily located in LMIC. Bridging this divide will require research, clinical and regulatory infrastructural development, capacity-building, training, an approval pathway and community adoption for success and sustainable affordability. In 2020, the Global Gene Therapy Initiative was formed to tackle the barriers to LMIC inclusion in gene therapy development. This working group includes diverse stakeholders from all sectors and has set a goal of introducing two gene therapy Phase I clinical trials in two LMIC, Uganda and India, by 2024. Here we report on progress to date for this initiative.

Innate lymphoid cell dysfunction during long-term suppressive antiretroviral therapy in an African cohort.

BACKGROUND: Innate lymphoid cells (ILC) are lymphoid lineage innate immune cells that do not mount antigen-specific responses due to their lack of B and T-cell receptors. ILCs are predominantly found at mucosal surfaces, as gatekeepers against invading infectious agents through rapid secretion of immune regulatory cytokines. HIV associated destruction of mucosal lymphoid tissue depletes ILCs, among other immune dysfunctions. Studies have described limited restoration of ILCs during the first three years of combined antiretroviral therapy (cART). Little is known about restoration of ILCs during long-term cART, particularly in sub-Saharan Africa which hosts increasing numbers of adults with at least a decade of cART. RESULTS: We examined phenotypes and function of ILCs from peripheral blood mononuclear cells after 12 years of suppressive cART. We report that ILC1 frequencies (T-BET + CD127 + and CD161 +) were higher in cART-treated HIV-infected relative to age-matched health HIV-negative adults; P = 0.04 whereas ILC precursors (ILCP) were comparable in the two groups (P = 0.56). Interferon gamma (IFN-γ) secretion by ILC1 was higher among cART-treated HIV-infected relative to HIV-negative adults (P = 0.03). CONCLUSION: HIV associated alteration of ILC persisted during cART and may likely affect the quality of host innate and adaptive immune responses during long-term cART.

Monocyte Dysfunction, Activation, and Inflammation After Long-Term Antiretroviral Therapy in an African Cohort.

BACKGROUND: Monocyte dysfunction may persist during antiretroviral therapy (ART). METHODS: Frozen peripheral blood mononuclear cells of 30 human immunodeficiency virus (HIV)-infected ART-treated adults with sustained viral suppression and CD4 counts ≥500 cells/µL were consecutively analyzed for monocyte phenotypes and function. RESULTS: Nonclassical monocytes (CD14+, CD16++), interleukin (IL)-1ß production, and expression of CD40 and CD86 were lower among ART-treated HIV-infected adults relative to age-matched HIV-negative adults (P = .01, P = .01, and P = .02, respectively). Intestinal fatty acid-binding protein, IL6, and soluble CD14 were higher among HIV-infected adults relative to HIV-negative adults (P = .0002, P = .04, and P = .0017, respectively). CONCLUSIONS: Further investigation is required to understand drivers of persistent monocyte activation and dysfunction.

Aberrant natural killer (NK) cell activation and dysfunction among ART-treated HIV-infected adults in an African cohort.

BACKGROUND: We examined NK cell phenotypes and functions after seven years of ART and undetectable viral loads (<50 copies/ml) with restored CD4 T-cell counts (≥500 cells/µl) and age-matched healthy-HIV-uninfected individuals from the same community. METHODS: Using flow-cytometry, NK cell phenotypes were described using lineage markers (CD56+/-CD16+/-). NK cell activation was determined by expression of activation receptors (NKG2D, NKp44 and NKp46) and activation marker CD69. NK cell function was determined by CD107a, granzyme-b, and IFN-gamma production. RESULTS: CD56 dim and CD56 bright NK cells were lower among ART-treated-HIV-infected than among age-matched-HIV-negative individuals; p = 0.0016 and p = 0.05 respectively. Production of CD107a (P = 0.004) and Granzyme-B (P = 0.005) was lower among ART-treated-HIV-infected relative to the healthy-HIV-uninfected individuals. NKG2D and NKp46 were lower, while CD69 expression was higher among ART-treated-HIV-infected than healthy-HIV-uninfected individuals. CONCLUSION: NK cell activation and dysfunction persisted despite seven years of suppressive ART with "normalization" of peripheral CD4 counts.

Diversity of vaginal microbiota in sub-Saharan Africa and its effects on HIV transmission and prevention.

The vaginal microbial community ("microbiota") is a key component of the reproductive health of women, providing protection against urogenital infections. In sub-Saharan Africa, there is a high prevalence of bacterial vaginosis, a condition defined by bacterial overgrowth and a shift away from a Lactobacillus-dominated profile toward increased percentages of strict anaerobic species. Bacterial vaginosis is associated with an increased risk of HIV acquisition and transmission, as well as an increased risk of acquiring other sexually transmitted infections, preterm births, and pelvic inflammatory disease. Vaginal microbiota, rich in taxa of strict anaerobic species, disrupts the mucosal epithelial barrier through secretion of metabolites and enzymes that mediate inflammation. Advancements in next-generation sequencing technologies such as whole-genome sequencing have led to deeper profiling of the vaginal microbiome and further study of its potential role in HIV pathogenesis and treatment. Until recently data on the composition of the vaginal microbiome in sub-Saharan Africa have been limited; however, a number of studies have been published that highlight the critical role of vaginal microbiota in disease and health in African women. This article reviews these recent findings and identifies gaps in knowledge about variations in female genital commensal bacteria that could provide vital information to improve the effectiveness of interventions to prevent HIV and other sexually transmitted infections. In addition, we review the effects of pregnancy, contraception, and sexual practices on vaginal microbiome and the potential of vaginal microbiota on HIV transmission and prevention. A better understanding of the role of vaginal microbiota in host susceptibility to HIV infection and its prevention among African women could inform the development of novel local and systemic interventions to minimize new HIV infections among high-risk women.

Sero-diagnosis of Active Mycobacterium tuberculosis Disease among HIV Co-infected Persons using Thymidylate Kinase based Antigen and Antibody Capture Enzyme Immuno-Assays.

BACKGROUND: Clinical and laboratory diagnosis of Active Tuberculosis (ATB) and latent Mycobacterium Tuberculosis (M. tuberculosis) infections (LTBI) among people living with HIV/AIDS (PLWHA) presents formidable challenges. In the past, WHO issued an advisory against the use of existing TB sero-diagnostics. Emerging evidence, however, points to a precision of TB sero-diagnostics based on secretory rather than structural M. tuberculosis antigens. We hypothesized that secretory levels of M. tuberculosis thymidylate kinase (TMKmt) can Designate ATBI from LTBI and no TB (NTB). Here, we report in-house validation studies of levels of TMKmt antigen (Ag) and host specific TMKmt antibody (Ab) amongst HIV +ve and HIV -ve participants. METHODS AND RESULTS: Direct TMKmt Ag and host specific IgG Ab detection EIAs were conducted on broadly consented, stored serum (N=281[Ag] vs. 214 [Ab] respective) samples stratified as either HIV +ve or HIV-ve ATB relative to LTBI and No TB. On one hand, UG-peptide 1 and its PAb-based EIAs accurately diagnosed ATB relative to LTBI and NTB among HIV +ve subjects {irrespectively: (a) Ag detection ATB=OD>0.490; 95% CI: 0.7446 to 0.8715 vs. LTBI=OD<0.490; 95% CI 0.4325 to 0.4829 vs. NTB=OD<0.26; 95% CI 0.1675 to 0.2567 and (b) TMKmt specific IgG detection ATB=OD>1.00; 95% CI 1.170 to 1.528 [HIV +ve] and 2.044 to 2.978 [HIV -ve] respectively vs. LTBI=OD<1.00; 95% CI 0.2690 to 0.6396 vs. NTB=OD<; 95% CI 0.1527 to 0.8751}. HIV -ve ATB presented with Ag levels greater than NTB and less than LTBI (i.e. ATB -ve=<0.490 ODs>0.26), but displayed better ant-TMKmt IgG responses (OD>2.00; 95% CI 2.044 to 2.978) relative to HIV +ve ATB (OD<1.600; 95% CI 1.170 to 1.528); suggesting a better control of M. tuberculosis-septicemia. On the other hand, UG-peptide 2 and its PAb-based EIAs did not demonstrate ATB diagnostic potential regardless of HIV sero-status, except towards designating NTB. CONCLUSIONS: TMKmt Ab and Ag detecting EIAs based on UG-peptide 1 and its derivative PAb can accurately demarcate ATB from LTBI and NTB among HIV +ve subjects.

Atorvastatin reduces T-cell activation and exhaustion among HIV-infected cART-treated suboptimal immune responders in Uganda: a randomised crossover placebo-controlled trial.

OBJECTIVE: T-cell activation independently predicts mortality, poor immune recovery and non-AIDS illnesses during combination antiretroviral therapy (cART). Atorvastatin showed anti-immune activation effects among HIV-infected cART-naïve individuals. We investigated whether adjunct atorvastatin therapy reduces T-cell activation among cART-treated adults with suboptimal immune recovery. METHODS: A randomised double-blind placebo-controlled crossover trial, of atorvastatin 80 mg daily vs. placebo for 12 weeks, was conducted among individuals with CD4 increase <295 cells/µl after seven years of suppressive cART. Change in T-cell activation (CD3 + CD4 + /CD8 + CD38 + HLADR+) and in T-cell exhaustion (CD3 + CD4 + /CD8 + PD1 + ) was measured using flow cytometry. RESULTS: Thirty patients were randomised, 15 to each arm. Atorvastatin resulted in a 28% greater reduction in CD4 T-cell activation (60% reduction) than placebo (32% reduction); P = 0.001. Atorvastatin also resulted in a 35% greater reduction in CD8-T-cell activation than placebo (49% vs. 14%, P = 0.0009), CD4 T-cell exhaustion (27% vs. 17% in placebo), P = 0.001 and CD8 T-cell exhaustion (27% vs. 16%), P = 0.004. There was no carry-over/period effect. Expected adverse events were comparable in both groups, and no serious adverse events were reported. CONCLUSION: Atorvastatin reduced T-cell immune activation and exhaustion among cART-treated adults in a Ugandan cohort. Atorvastatin adjunct therapy should be explored as a strategy to improve HIV treatment outcomes among people living with HIV in sub-Saharan Africa.

Low antigen-specific CD4 T-cell immune responses despite normal absolute CD4 counts after long-term antiretroviral therapy an African cohort.

BACKGROUND: CD4 counts guide antiretroviral therapy (ART) initiation and prophylaxis for opportunistic infections. It is unclear whether normal CD4 counts translate to normalized immune responses among ART-treated adults. We compared antigen-specific CD4 T-cell immune responses among ART-treated adults with CD4≥500cells/µl, optimal immune responders (O-IR), and their age-matched healthy HIV-negative counterparts. METHODS: In a sample-based case-control study, cryopreserved peripheral blood mononuclear cells from 15 O-IR after 7 years of ART and 15 healthy controls, were analyzed for CD4+ T-cell proliferation using CFSE dye and cytokine production. RESULTS: CD4 T-cell proliferation, upon stimulation with PPD and pneumococcal polysaccharide antigen, was lower among O-IR relative to HIV-negative controls; p=0.016 and p=0.016 respectively. CD4 T-cell production of IL-2 was lower among O-IR relative to HIV-negative control p=0.002. CD4 T-cell proliferation upon stimulation with SEB and CMV antigens was similar among O-IR and HIV-negative controls p=0.971 and p=0.480, respectively, and so was IL-4 and IFN γ production; p=0.528 and p=0.892, respectively. CONCLUSION: Seven years of suppressive ART caused partial CD4 T-cell function recovery in an African HIV treatment cohort, despite restoration of CD4 T-cell counts to levels≥500cells/µl. The role innate immunity in the recovery of immune function during long-term ART should be investigated to guide decisions on continued prophylaxis against opportunistic infections.

CD4 T-cell activation and reduced regulatory T-cell populations are associated with early development of cataracts among HIV-infected adults in Uganda.

BACKGROUND: Cataracts contribute 12% of visual loss among HIV-infected adults in Uganda. Immuno-pathogenesis of cataracts may differ among HIV-infected individuals; thus the need for innovative therapeutic interventions among HIV-infected adults. METHODS: In a laboratory based case-control study, nested in a clinical/surgical community outreach camp, 50 adults with cataracts eligible for surgery were selected consecutively. HIV testing was done for individuals with unknown HIV sero-status. Peripheral Blood Mononuclear Cells (PBMC) were collected from all HIV-positive-adults-with-cataracts (cases) and HIV-negative-adults-with-cataracts (comparative group) and age-matched HIV-negative and HIV-positive-adults-without-cataracts (comparative group). Treg were measured as CD3+CD4+FoxP3+CD25+(Bright) and immune activation as CD3+CD4+CD38+HALDR+ using a Facs Canto II flowcytometer. Mann Whitney test was used to compare expression among the four groups. RESULTS: Of 50 adults operated for cataracts, 24 (48%) were female, 25 (50%) were HIV-positive. HIV-positive-individuals had cataracts earlier [median; Inter-quartile Range (IQR); 49 (44-53) years] than HIV-negative [70 (IQR 59-75) years]; p=0.0005. Treg were lower among individuals with cataracts irrespective of HIV status; p=0.001; but comparable among younger HIV-positive and elderly HIV-negative with cataracts; p=0.301. Immune activation levels were comparable among HIV-positive and HIV-negative individuals with cataracts. However, HIV-positive-individuals with cataracts expressed higher levels of immune activation than HIV-positive-individuals without cataracts; p=0.012 and HIV-negative-individuals-with-cataracts expressed higher levels of immune activation that HIV-negative-without-cataracts; p<0.0001. CONCLUSION: CD4 T-cell activation and reduced regulatory T-cell populations were associated with cataracts among adults aging with HIV. We recommend studies on clinical relevance of immune modulation in the prevention of early development of cataracts among adults aging with HIV in Africa.

High CD56++CD16- natural killer (NK) cells among suboptimal immune responders after four years of suppressive antiretroviral therapy in an African adult HIV treatment cohort.

BACKGROUND: Up to 40% of HIV-infected individuals receiving Highly Active Antiretroviral Therapy (HAART) have poor CD4+ T-cell recovery. The role of natural killer (NK) cells in immune recovery during HAART is not well understood. We described the profiles of NK cell subsets and their expression of activating receptor, NKG2D and cytotoxicity receptor NKp46 among suboptimal immune responders to despite four years of suppressive HAART. METHODS: A case control study utilized frozen peripheral blood mononuclear cells (PBMC) from a cohort of HIV-infected adults that initiated HAART in 2004/5, at CD4 < 200 cells/µl. Cases were 'suboptimal' responders; patients within the lowest quartile of CD4+ T-cell reconstitution, with a median CD4 count increase of 129 (-43-199) cells/µl (difference between CD4 count at baseline and after 4 years of HAART) and controls were 'super-optimal' responders; patients within the highest quartile of CD4 T-cell reconstitution with a median CD4 count increase of 528 (416-878) cells/µl). Expression of NK cell lineage markers (CD56+/-CD16+/-) and receptors NKG2D and NKp46, was measured among PBMC from 29 cases of 'suboptimal' responders' and 23 controls of 'super-optimal responders', and compared among 'suboptimal' and 'super-optimal' responders. NK cell populations were compared using the Holm Sidak multiple comparison test and p values < 0.05 were considered statistically significant. Data was analyzed using FLOWJO and GraphPad Prism 6. RESULTS: 'Suboptimal responders' had a higher proportion of cytokine producing CD56(++)CD16(+/-) (CD56bri) NK cells than the 'super-optimal responders' p = 0.017, and CD56(neg) NK cells were lower among suboptimal than super-optimal responders (p = 0.007). The largest NK cell subset, CD56(dim), was comparable among suboptimal responders and 'super-optimal immune responders'. Expression of NKG2D and NKp46 receptors on NK cell subsets (CD56(bri), CD56(neg) and CD56(dim)), was comparable among 'suboptimal' and 'super-optimal' immune responders. CONCLUSIONS: The pro-inflammatory CD56++CD16-- NK cells were higher among 'suboptimal' responders relative to 'super-optimal' responders, despite four years of suppressive HAART. Alteration of NK cell populations could inhibit host immune responses to infections among suboptimal responders. We recommend further analysis of NK cell function among suboptimal immune responders in order to inform targeted interventions to optimize immune recovery among HAART-treated adults.