Effect of baseline micronutrient and inflammation status on CD4 recovery post-cART initiation in the multinational PEARLS trial

Nicotinamide mononucleotide impacts HIV-1 infection by modulating immune activation in T lymphocytes and humanized mice

BACKGROUND

HIV-1-associated immune activation drives CD4+ T cell depletion and the development of acquired immunodeficiency syndrome. We aimed to determine the role of nicotinamide mononucleotide (NMN), the direct precursor of nicotinamide adenine dinucleotide (NAD) co-enzyme, in CD4+ T cell modulation during HIV-1 infection.

METHODS

We examined HIV-1 integrated DNA or transcribed RNA, intracellular p24 protein, and T cell activation markers in CD4+ T cells including in vitro HIV-1-infected cells, reactivated patient-derived cells, and in HIV-1-infected humanized mice, under NMN treatment. RNA-seq and CyTOF analyses were used for investigating the effect of NMN on CD4+ T cells.

FINDINGS

We found that NMN increased the intracellular NAD amount, resulting in suppressed HIV-1 p24 production and proliferation in infected CD4+ T cells, especially in activated CD25+CD4+ T cells. NMN also inhibited CD25 expression on reactivated resting CD4+ T cells derived from cART-treated people living with HIV-1 (PLWH). In HIV-1-infected humanized mice, the frequency of CD4+ T cells was reconstituted significantly by combined cART and NMN treatment as compared with cART or NMN alone, which correlated with suppressed hyperactivation of CD4+ T cells.

INTERPRETATION

Our results highlight the suppressive role of NMN in CD4+ T cell activation during HIV-1 infection. It warrants future clinical investigation of NMN as a potential treatment in combination with cART in PLWH.

FUNDING

This work was supported by the Hong Kong Research Grants Council Theme-Based Research Scheme (T11-706/18-N), University Research Committee of The University of Hong Kong, the Collaborative Research with GeneHarbor (Hong Kong) Biotechnologies Limited and National Key R&D Program of China (Grant2021YFC2301900).

Metformin may be a viable adjunctive therapeutic option to potentially enhance immune reconstitution in HIV-positive immunological non-responders

ABSTRACT

Incomplete immune reconstitution remains a global challenge for human immunodeficiency virus (HIV) treatment in the present era of potent antiretroviral therapy (ART), especially for those individuals referred to as immunological non-responders (INRs), who exhibit dramatically low CD4 + T-cell counts despite the use of effective antiretroviral therapy, with long-term inhibition of viral replication. In this review, we provide a critical overview of the concept of ART-treated HIV-positive immunological non-response, and also explain the known mechanisms which could potentially account for the emergence of immunological non-response in some HIV-infected individuals treated with appropriate and effective ART. We found that immune cell exhaustion, combined with chronic inflammation and the HIV-associated dysbiosis syndrome, may represent strategic aspects of the immune response that may be fundamental to incomplete immune recovery. Interestingly, we noted from the literature that metformin exhibits properties and characteristics that may potentially be useful to specifically target immune cell exhaustion, chronic inflammation, and HIV-associated gut dysbiosis syndrome, mechanisms which are now recognized for their critically important complicity in HIV disease-related incomplete immune recovery. In light of evidence discussed in this review, it can be seen that metformin may be of particularly favorable use if utilized as adjunctive treatment in INRs to potentially enhance immune reconstitution. The approach described herein may represent a promising area of therapeutic intervention, aiding in significantly reducing the risk of HIV disease progression and mortality in a particularly vulnerable subgroup of HIV-positive individuals.

The role of vitamin D status on treatment outcome among HIV- infected children receiving care in Kisumu County, Kenya

Background

Kenya has a paediatric HIV burden of nearly 140,000 children, of which only 48% of those on antiretroviral therapy (ART) have achieved the desired viral suppression possibly due to vitamin D deficiency. We explored the influence of vitamin D levels on treatment outcome.

Method

We performed a cross-sectional study of 196 participants aged 3 - 14 years; among them 98 HIV infected who received treatment between 2019 - 2020 in Jaramogi Oginga Odinga Teaching and Referral Hospital, Kenya. The exposure was vitamin D levels, including deficient (<20 ng/ml), insufficient (≥20 - <30 ng/ml), and sufficient (30 - 50ng/ml). The outcome was optimal immune recovery (CD4 ≥ 500 cells/mm3) and optimal viral suppression (viral load ≤ 200 copies/ml). We compared difference in means for each vitamin D category between HIV infected and uninfected using independent t-test, multiple comparisons of vitamin D levels among age categories using ANOVA and post hoc test and Pearson correlation to correlate vitamin D levels, CD4 and viral load of HIV infected children.

Results

Compared with HIV uninfected, HIV infected recorded mean age ± standard deviation of10.65±2.17 years with 39(39.8%) males vs. 6.68±2.81 years with 52(53.1%) males p<0.001; and the difference in vitamin D mean levels was statistically significant [28.21 ± 6.39 infected vs.30.88 ± 6.62 uninfected] t = 2.94, df =194, p = 0.004, 95%CI (0.90 - 4.59). Among age categories, mean vitamin D varied significantly F (2,193) = 10.68, p =0.001; with higher levels observed between 1-4 years category {mean difference 4.64ng/ml, p = 0.02, [95%CI 1.49 - 7.78]} and 5-9 years category {mean difference 4.33ng/ml, p = 0.001, [95%CI 1.89 - 6.38]} as compared to 10 - 14 years respectively.Additionally, children with optimal immune recovery recorded higher proportion of vitamin D deficiency and insufficiency (12.24% and 42.86%) as compared with sub optimally recovered 1.02% and 4.08%); while children with optimal viral suppression recorded higher proportion of vitamin D deficiency and insufficiency (8.16% and 30.61%) as compared with sub optimally suppressed (5.1% and 16.3%).

Conclusion

Infections with HIV suppresses levels of vitamin D, but this has no influence on CD4 counts and viral load status in children receiving ART.

Comparative Assessment of Serum Selenium Status in HIV-Infected and Non-infected Children: A Pilot Study in a Tertiary Hospital in Nigeria

Background Selenium is an essential micronutrient that plays a crucial role in a wide range of physiological processes, including immune responses. Selenium deficiency has been recognized as an associated factor in the progression of HIV to advanced HIV disease and/or mortality. Although selenium supplementation has been shown to reduce hospitalizations and improve cellular immunity, the evidence remains mixed. This study aimed to determine the prevalence of selenium deficiency and its relationship with HIV disease markers in HIV-infected children at the Lagos University Teaching Hospital. Methodology This is a cross-sectional, comparative, pilot study of plasma concentrations of selenium in HIV-infected (n = 30) and non-infected (n = 20) children enrolled in the pediatric HIV clinic of the Lagos University Teaching Hospital, Lagos, Nigeria, from May 2019 to May 2021. HIV-infected children were on stable antiretroviral therapy (ART) with an undetectable viral load. The serum concentration of selenium was measured using the automated atomic absorption spectrophotometer (hydride generation method). Logistic regression was used to study the effect of selenium status on the levels of HIV disease markers (CD4 count, viral load, weight, opportunistic infections) in the study participants. Results The median age of all participants was nine (4-12) years, with 74% being boys. The mean selenium concentrations were lower in HIV-infected children (91.1 ± 12.0 µg/L) compared to the comparison group without HIV (147.8 ± 4.9 µg/L) (p = 0.001). After controlling for age, ART duration, markers of HIV infection, and other potentially confounding variables, participants with selenium deficiency had approximately 11-fold odds of increased hospital admissions (adjusted odds ratio = 10.57, 95% confidence interval = 1.58 to 70.99; p = 0.015). Conclusions In this study, selenium concentrations were significantly lower in HIV-infected children than in the HIV-negative comparison group. Lower serum selenium concentrations were associated with increased hospitalizations. Although our findings suggest the potential need for selenium supplementation for children living with HIV in Nigeria, further studies are warranted to determine the safety and efficacy of selenium supplementation in this key population.

The role of vitamin B12 in viral infections: a comprehensive review of its relationship with the muscle-gut-brain axis and implications for SARS-CoV-2 infection

This comprehensive review establishes the role of vitamin B12 as adjunct therapy for viral infections in the treatment and persistent symptoms of COVID-19, focusing on symptoms related to the muscle-gut-brain axis. Vitamin B12 can help balance immune responses to better fight viral infections. Furthermore, data from randomized clinical trials and meta-analysis indicate that vitamin B12 in the forms of methylcobalamin and cyanocobalamin may increase serum vitamin B12 levels, and resulted in decreased serum methylmalonic acid and homocysteine concentrations, and decreased pain intensity, memory loss, and impaired concentration. Among studies, there is much variation in vitamin B12 doses, chemical forms, supplementation time, and administration routes. Larger randomized clinical trials of vitamin B12 supplementation and analysis of markers such as total vitamin B12, holotranscobalamin, total homocysteine and methylmalonic acid, total folic acid, and, if possible, polymorphisms and methylation of genes need to be conducted with people with and without COVID-19 or who have had COVID-19 to facilitate the proper vitamin B12 form to be administered in individual treatment.

Vitamin D: role in chronic and acute diseases

Vitamin D is involved in bone health by promoting calcium absorption in the gut and maintaining serum calcium and phosphate concentrations, and by its action on bone growth and reorganization through osteoblasts and osteoclasts cells. Moreover, during the last three decades, novel actions of vitamin D have been discovered. Several systematic reviews and meta-analyses have shown links between serum vitamin D levels and non-communicable diseases. In line with these findings, a wide number of studies have suggested associations of vitamin D deficiency (VDD) with respiratory tract infections, osteoporosis, and other chronic and metabolic diseases such as obesity, metabolic syndrome, type 2 diabetes mellitus (T2DM), cancer, rheumatoid arthritis (RA), and inflammatory bowel disease (IBD). Vitamin D also exerts important actions in the clinical course of infectious and other acute diseases, particularly respiratory bacterial infections, tuberculosis, and virus infections, e.g., those generated by human immunodeficiency and SARS-CoV-2 (COVID-19) viruses. The present article aimed to update the role of vitamin D in chronic and acute diseases.

•

To know the role of vitamin D in the prevention and treatment of non-communicable chronic diseases.

•

To understand how vitamin D deficiency is related to obesity, insulin resistance and metabolic syndrome, type 2 diabetes, cancer, rheumatoid arthritis, osteoporosis, chronic pulmonary obstructive disease, and inflammatory bowel disease.

•

To know the function of vitamin D in the prevention and treatment of acute infectious diseases of bacterial and viral origins, namely respiratory infections.

•

To understand the role of vitamin D in the prevention of HIV and SARS-Cov2 infections

•

To know how vitamin D status affects the course of critical illness diseases

Increased Risk of Vitamin D Deficiency Among HIV-Infected Individuals: A Systematic Review and Meta-Analysis

Background: Human immunodeficiency virus (HIV) infection is a heavy burden worldwide. Observational studies have reported a high prevalence of vitamin D deficiency (VDD) among people living with HIV (PLWH). However, its deficiency is also a global health problem. Therefore, we conducted a meta-analysis and systemic review to compare differences between HIV-infected subjects and non-HIV-infected subjects.

Methods: We searched PubMed, Web of Science, Embase, and Cochrane library. We extracted data, including demographic information, study type, vitamin D-related values, and HIV-related values, ultimately including 15 studies after removing duplicates and screening titles, abstracts, and full texts and finally performing a meta-analysis in terms of vitamin D level and vitamin D deficiency prevalence.

Results: Regarding VDD prevalence, the HIV vs. the non-HIV group had an odds ratio of 1.502 (95% CI, 1.023–2.205; P = 0.038). In the subgroup analysis, the odds ratios were 1.647 (95% CI, 1.020–2.659; P = 0.041; I² = 94.568) from 7 studies (age over 40), 2.120 (95% CI, 1.122–4.008; P = 0.021; I² = 0.000) from 2 studies (BMI less than or equal to 25), 1.805 (95% CI, 1.373–2.372; P = 0.042; I² = 74.576) from 7 studies (latitude <40), 2.120 (95% CI, 1.122–4.088; P = 0.021; I² = 0.000) from 2 studies (only included male participants), and 2.296 (95% CI, 1.287–4.097; P = 0.005; I² = 19.927) from 3 studies (only included ART-experienced participants). Thirteen studies were deemed to have moderate quality, while two had high quality.

Conclusions: HIV infected subjects are prone to have VDD compared with general population. ART, older age, lower BMI, lower latitude and male sex may present risk factors for VDD in PLWH.

Systematic Review Registration:https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=228096.

RALDH Activity Induced by Bacterial/Fungal Pathogens in CD16+ Monocyte-Derived Dendritic Cells Boosts HIV Infection and Outgrowth in CD4+ T Cells

HIV reservoirs persist in gut-homing CD4⁺ T cells of people living with HIV and receiving antiretroviral therapy, but the antigenic specificity of such reservoirs remains poorly documented. The imprinting for gut homing is mediated by retinoic acid (RA), a vitamin A-derived metabolite produced by dendritic cells (DCs) exhibiting RA-synthesizing (RALDH) activity. RALDH activity in DCs can be induced by TLR2 ligands, such as bacterial peptidoglycans and fungal zymosan. Thus, we hypothesized that bacterial/fungal pathogens triggering RALDH activity in DCs fuel HIV reservoir establishment/outgrowth in pathogen-reactive CD4⁺ T cells. Our results demonstrate that DCs derived from intermediate/nonclassical CD16⁺ compared with classical CD16^- monocytes exhibited superior RALDH activity and higher capacity to transmit HIV infection to autologous Staphylococcus aureus-reactive T cells. Exposure of total monocyte-derived DCs (MDDCs) to S. aureus lysates as well as TLR2 (zymosan and heat-killed preparation of Listeria monocytogenes) and TLR4 (LPS) agonists but not CMV lysates resulted in a robust upregulation of RALDH activity. MDDCs loaded with S. aureus or zymosan induced the proliferation of T cells with a CCR5⁺integrin β7⁺CCR6⁺ phenotype and efficiently transmitted HIV infection to these T cells via RALDH/RA-dependent mechanisms. Finally, S. aureus- and zymosan-reactive CD4⁺ T cells of antiretroviral therapy-treated people living with HIV carried replication-competent integrated HIV-DNA, as demonstrated by an MDDC-based viral outgrowth assay. Together, these results support a model in which bacterial/fungal pathogens in the gut promote RALDH activity in MDDCs, especially in CD16⁺ MDDCs, and subsequently imprint CD4⁺ T cells with gut-homing potential and HIV permissiveness. Thus, nonviral pathogens play key roles in fueling HIV reservoir establishment/outgrowth via RALDH/RA-dependent mechanisms that may be therapeutically targeted.

Anemia, Iron Status, and HIV: A Systematic Review of the Evidence

People living with HIV (PLWHIV) are at high risk of anemia due to inadequate iron intake, HIV and opportunistic infections, and inflammation, and as a side effect of antiretroviral therapy. Though iron supplementation can reduce iron deficiency anemia (IDA) in the general population, its role in anemia and in the health of PLWHIV is unclear due to concerns that iron supplementation may increase HIV replication and risk of opportunistic infections. We systematically reviewed the evidence on indicators of iron status, iron intake, and clinical outcomes among adults and children with HIV. The evidence suggests that anemia is associated with an increased risk of all-cause mortality and incident tuberculosis among HIV-infected individuals, regardless of anemia type, and the magnitude of the risk is greater with more severe anemia. High serum ferritin is associated with adverse clinical outcomes, although it is unclear if this is due to high iron or inflammation from disease progression. One large observational study found an increased risk of all-cause mortality among HIV-infected adults if they received iron supplementation. Published randomized controlled trials of iron supplementation among PLWHIV tend to have small sample sizes and have been inconclusive in terms of effectiveness and safety. Large randomized trials exploring approaches to safely and effectively provide iron supplementation to PLWHIV are warranted.

Hypervitaminosis A is associated with immunological non-response in HIV-1-infected adults: a case-control study

For people living with HIV, determinants of immunological non-response (INR) to combined antiretroviral therapy (cART) have not been fully elucidated. In a case-control study, we evaluated the influence of the nutritional and antioxidant status in HIV-1 adults whose cART was initiated between January 2001 and December 2013. Cases had persistent CD4 counts < 350/μL vs. > 350/μL for controls, after at least 2 years of cART with persistent viral loads (VL) < 50 copies/mL. Twelve cases and twenty-eight control subjects with the same CD4 count at cART initiation were compared for their nutritional and antioxidant status after age adjustment at dosage assessment. Patients were predominantly male (70%), Caucasian (82%) and at AIDS stage (62%). The median age was 53, and the median CD4 count was 245/mm³ for cases and 630/mm³ for controls after a median time of 7 years on cART. Despite higher energy intakes in cases, anthropometric data was comparable between groups who had similar vitamins B9/B12/C/D/E, zinc, citrulline and glutamine levels. Nine cases (75%) and 8 controls (29%) had hypervitaminosis A (> 2.70 μmol/L) (p = 0.030). Cases had lower erythrocyte resistance when exposed to a controlled free radical attack (p = 0.014). Most cases had hypervitaminosis A and altered antioxidant capacities that could affect immunological response. Wide-scale studies are required, but in the meantime, screening of their vitamin A status must be encouraged in these patients.

New signatures of poor CD4 cell recovery after suppressive antiretroviral therapy in HIV-1-infected individuals: involvement of miR-192, IL-6, sCD14 and miR-144

Up to 40% of newly diagnosed cases of HIV-1 infection are late diagnoses, with a profound decrease in CD4 cell counts in many cases. One-third of these individuals do not achieve optimal CD4 cell recovery (OR) after suppressive antiretroviral treatment (ART). This retrospective/longitudinal study of poor recovery (PR) included 79 HIV-1-infected individuals with CD4 count <200 cells/mm³ (25 PR and 54 OR) before ART. After suppressive ART, 21 PR and 24 OR individuals were further analysed, including paired samples. Selected miRs and plasma inflammatory markers were determined to investigate their potential predictive/diagnostic value for poor recovery. miR-192, IL-6 and sCD14 were independently associated with CD4 recovery before ART (p = 0.031, p = 0.007, and p = 0.008, respectively). The combination of these three factors returned a good discrimination (predictive value for PR) value of 0.841 (AUC, p < 0.001). After suppressive ART, miR-144 was independently associated with CD4 recovery (p = 0.017), showing a moderate discrimination value of 0.730 (AUC, p = 0.008) for PR. Our study provides new evidence on the relationship between miRs and HIV-1 infection that could help improve the management of individuals at HIV-1 diagnosis. These miRs and cytokines signature sets provide novel tools to predict CD4 cell recovery and its progression after ART.

Incomplete immune reconstitution in HIV/AIDS patients on antiretroviral therapy: Challenges of immunological non-responders

The morbidity and mortality of HIV type-1 (HIV-1)-related diseases were dramatically diminished by the grounds of the introduction of potent antiretroviral therapy, which induces persistent suppression of HIV-1 replication and gradual recovery of CD4⁺ T-cell counts. However, ∼10-40% of HIV-1-infected individuals fail to achieve normalization of CD4⁺ T-cell counts despite persistent virological suppression. These patients are referred to as "inadequate immunological responders," "immunodiscordant responders," or "immunological non-responders (INRs)" who show severe immunological dysfunction. Indeed, INRs are at an increased risk of clinical progression to AIDS and non-AIDS events and present higher rates of mortality than HIV-1-infected individuals with adequate immune reconstitution. To date, the underlying mechanism of incomplete immune reconstitution in HIV-1-infected patients has not been fully elucidated. In light of this limitation, it is of substantial practical significance to deeply understand the mechanism of immune reconstitution and design effective individualized treatment strategies. Therefore, in this review, we aim to highlight the mechanism and risk factors of incomplete immune reconstitution and strategies to intervene.

Selenium, Selenoproteins, and Immunity

Selenium is an essential micronutrient that plays a crucial role in development and a wide variety of physiological processes including effect immune responses. The immune system relies on adequate dietary selenium intake and this nutrient exerts its biological effects mostly through its incorporation into selenoproteins. The selenoproteome contains 25 members in humans that exhibit a wide variety of functions. The development of high-throughput omic approaches and novel bioinformatics tools has led to new insights regarding the effects of selenium and selenoproteins in human immuno-biology. Equally important are the innovative experimental systems that have emerged to interrogate molecular mechanisms underlying those effects. This review presents a summary of the current understanding of the role of selenium and selenoproteins in regulating immune cell functions and how dysregulation of these processes may lead to inflammation or immune-related diseases.