Natural Killer Cells Phenotype in Antiretroviral Naïve HIV-1 Infected People Living in Cameroon

The impact of antiretroviral naïve HIV-1 infection on the modulation of Natural Killer (NK) cells phenotype has not been fully assessed. This study aimed to define the phenotype of NK cell in the context of antiretroviral naïve HIV-1 infection. A total of 85 ARV naïve HIV-1 infected and 55 healthy individuals were included in the study. Purified NK cells alongside bulk Peripheral Blood Mononuclear Cells (PBMC) were surface stained with fluorochrome conjugated antibodies and samples were acquired using a BD FACS canto II flow cytometer. A down-regulation of CD56 + /CD16 - and CD56 + /CD16 + NK cells (p= 0.003), and a significant expansion (p= 0.03) of CD56 - /CD16 + NK cells subset was observed in ARV naïve HIV-1 infection. The high expression of both CD38 (p= 0.02) and HLA-DR (p=0.001) in the CD56-/CD16+ NK cells subset, shows the activation status of NK cells from HIV-1 infected people. A reduced expression of activating markers NKp44 and NKp30 and the down regulation of NKG2A was observed  in CD56+/CD16- and CD56+/CD16+ NK cells from HIV-1 infected people (p= 0.006, p= 0.009, respectively).  Antiretroviral naive HIV-1 infected people living in Cameroon show a differential modulation of NK cell phenotype relative to HIV negative controls

Inflammatory profile of vertically HIV-1 infected adolescents receiving ART in Cameroon: a contribution toward optimal pediatric HIV control strategies

Antiretroviral therapy (ART) has improved the lifespan of people living with HIV. However, their immune system remains in a state of sustained activation/inflammation, which favors viral replication and depletion of helper T-cells with varying profiles according to ART-response. We herein sought to ascertain the inflammatory profile of adolescents living with perinatal HIV-1 infection (ALPHI) receiving ART in an African context. In this cross-sectional and comparative study among ART-experienced ALPHI in Yaoundé-Cameroon, HIV-1 RNA was measured by Abbott Real-time PCR; CD4 cells were enumerated using flow cytometry; serum cytokines were measured by ELISA; HIV-1 proviral DNA was genotyped by Sanger-sequencing; and archived drug resistance mutations (ADRMs) were interpreted using Stanford HIVdb.v9.0.1. Overall, 73 adolescents were enrolled (60 ALPHI and 13 HIV-1 negative peers) aged 15 (13-18) years; 60.00% were female. ART median duration was 92 (46-123) months; median viral load was 3.99 (3.17-4.66) RNA Log10 (copies)/mL and median CD4 count was 326 (201-654) cells/mm3. As compared to HIV-negative adolescents, TNFα was highly expressed among ALPHI (p<0.01). Following a virological response, inflammatory cytokines (IFNγ and IL-12), anti-inflammatory cytokines (IL-4 and IL-10) and inflammation-related cytokines (IL-6 and IL-1β) were highly expressed with viral suppression (VS) vs. virological failure (VF), while the chemokine CCL3 was highly expressed with VF (p<0.01). Regarding the immune response, the inflammatory cytokine TNFα was highly expressed in those that are immunocompetent (CD4≥500 cell/mm3) vs. immunocompromised (CD4<500 cell/mm3), p ≤ 0.01; while chemokine CCL2 was highly expressed in the immunocompromised (p<0.05). In the presence of ADRMs, IL-4 and CCL3 were highly expressed (p=0.027 and p=0.043 respectively). Among ART-experienced ALPHI in Cameroon, the TNFα cytokine was found to be an inflammatory marker of HIV infection; IFNγ, IL-1β, IL-6, and IL-12 are potential immunological markers of VS and targeting these cytokines in addition to antiretroviral drugs may improve management. Moreover, CCL3 and CCL2 are possible predictors of VF and/or being immunocompromised and could serve as surrogates of poor ART response

Inflammatory profile of vertically HIV-1 infected adolescents receiving ART in Cameroon: a contribution toward optimal pediatric HIV control strategies

Antiretroviral therapy (ART) has improved the lifespan of people living with HIV. However, their immune system remains in a state of sustained activation/inflammation, which favors viral replication and depletion of helper T-cells with varying profiles according to ART-response. We herein sought to ascertain the inflammatory profile of adolescents living with perinatal HIV-1 infection (ALPHI) receiving ART in an African context. In this cross-sectional and comparative study among ART-experienced ALPHI in Yaoundé-Cameroon, HIV-1 RNA was measured by Abbott Real-time PCR; CD4 cells were enumerated using flow cytometry; serum cytokines were measured by ELISA; HIV-1 proviral DNA was genotyped by Sanger-sequencing; and archived drug resistance mutations (ADRMs) were interpreted using Stanford HIVdb.v9.0.1. Overall, 73 adolescents were enrolled (60 ALPHI and 13 HIV-1 negative peers) aged 15 (13-18) years; 60.00% were female. ART median duration was 92 (46-123) months; median viral load was 3.99 (3.17-4.66) RNA Log10 (copies)/mL and median CD4 count was 326 (201-654) cells/mm3. As compared to HIV-negative adolescents, TNFα was highly expressed among ALPHI (p<0.01). Following a virological response, inflammatory cytokines (IFNγ and IL-12), anti-inflammatory cytokines (IL-4 and IL-10) and inflammation-related cytokines (IL-6 and IL-1β) were highly expressed with viral suppression (VS) vs. virological failure (VF), while the chemokine CCL3 was highly expressed with VF (p<0.01). Regarding the immune response, the inflammatory cytokine TNFα was highly expressed in those that are immunocompetent (CD4≥500 cell/mm3) vs. immunocompromised (CD4<500 cell/mm3), p ≤ 0.01; while chemokine CCL2 was highly expressed in the immunocompromised (p<0.05). In the presence of ADRMs, IL-4 and CCL3 were highly expressed (p=0.027 and p=0.043 respectively). Among ART-experienced ALPHI in Cameroon, the TNFα cytokine was found to be an inflammatory marker of HIV infection; IFNγ, IL-1β, IL-6, and IL-12 are potential immunological markers of VS and targeting these cytokines in addition to antiretroviral drugs may improve management. Moreover, CCL3 and CCL2 are possible predictors of VF and/or being immunocompromised and could serve as surrogates of poor ART response

Characterization of the Viral Reservoirs Among HIV-1 Non-B Vertically Infected Adolescents Receiving Antiretroviral Therapy: Protocol for an Observational and Comparative Study in Cameroon

BackgroundAntiretroviral therapy (ART) can bring HIV-1 levels in blood plasma to the undetectable level and allow a near-normal life expectancy for HIV-infected individuals. Unfortunately, ART is not curative and must be taken for life, because within a few weeks of treatment cessation, HIV viremia rebounds in most patients except for rare elite or posttreatment controllers of viremia. The primary source of this rebound is the highly stable reservoir of latent yet replication-competent HIV-1 proviruses integrated into the genomic DNA of the resting memory cluster of differentiation 4 (CD4+) T cells. To achieve a cure for HIV, understanding the cell reservoir environment is of paramount importance. The size and nature of the viral reservoir might vary according to the timing of therapy, therapeutic response, ART duration, and immune response. The mechanisms of reservoir maintenance generally depend on the levels/type of immune recognition; in addition, the dynamics of viral persistence are different between pediatric and adult populations. This difference could become more evident as children grow toward adolescence. ObjectiveWe aim to characterize the HIV reservoirs and their variability as per the virological and immunological profiles of HIV-1 non-B vertically infected adolescents receiving ART in Cameroon during the Adolescents' Viral Reservoirs study to provide accurate and reliable data for HIV cure research. MethodsThis study will involve HIV-1 non-B vertically infected adolescents selected from an existing cohort in our institution. Blood samples will be collected for analyzing immunological/virological profiles, including CD4/CD8 count, plasma viral load, immune activation/inflammatory markers, genotyping, and quantification of HIV-1 viral reservoirs. We will equally recruit an age-matched group of HIV-negative adolescents as control for immunological profiling. ResultsThis study received funding in November 2021 and was approved by the national institutional review board in December 2021. Sample collection will start in November 2022, and the study will last for 18 months. The HIV-1 sequences generated will provide information on the circulating HIV-1 subtypes to guide the selection of the most appropriate ART for the participants. The levels of immune biomarkers will help determine the immune profile and help identify factors driving persistent immune activation/inflammation in HIV-infected adolescents compared to those in HIV-uninfected adolescents. Analysis of the virological and immunological parameters in addition to the HIV-1 reservoir size will shed light on the characteristics of the viral reservoir in adolescents with HIV-1 non-B infection. ConclusionsOur findings will help in advancing the knowledge on HIV reservoirs, in terms of size and genetic variability in adolescents living with HIV. Such evidence will also help in understanding the effects of ART timing and duration on the size of the reservoirs among adolescents living with HIV—a unique population from whom the findings generated will largely contribute to designing functional cure strategies. International Registered Report Identifier (IRRID)PRR1-10.2196/4147

Characterisation of HIV-1 reservoirs in paediatric populations: protocol for a systematic review and meta-analysis

Introduction The success of antiretroviral therapy (ART) has changed HIV from a deadly to a chronic infection, thus increasing the transitioning from infancy toward adulthood. However, the virostatic nature of antiretrovirals maintains viruses in sanctuaries, with reactivation potentials. Because current ARTs are very limited for children, the emergence of new HIV epidemics driven by HIV drug-resistance mutations is favoured. Our systematic review aims to estimate the global burden of archived drug-resistance mutations (ADRMs) and the size of reservoir (HIV-1 DNA load), and their associated factors in children and adolescents.Methods and analysis Papers from the PubMed/MEDLINE, Google Scholar, ScienceDirect, African Journals Online and Academic Medical Education Databases will be systematically identified using the keywords: “HIV-1 reservoirs”, “viral reservoirs”, “HIV-1 DNA”, infants, adolescents, child and children, linked by the following Boolean operators: ‘OR’ and ‘AND’. Randomised and non-randomised trials, cohort studies and cross-sectional studies published in French or English from January 2002 will be included, while case reports, letters, comments, reviews, systematic reviews and meta-analyses, and editorials will be excluded. All studies describing data on ADRMs, HIV-1 DNA load and/or immunological markers among children/adolescents will be eligible. A random-effects model will be used to calculate the pooled prevalence of ADRMs. Data will be reported according to type of viral reservoir (peripheral blood mononuclear cells, CD4 cells), geographical location (country/continent), ethnicity/race, age (infants vs adolescents), gender, HIV-1 clades, ART exposure (naïve vs treated, drug class, type of regimen, age at ART initiation and treatment duration), WHO clinical staging (I, II, III, IV), immune status (immune compromised vs immune competent) and virological response (viraemic vs non-viraemic). Multivariate logistic regression will be performed to determine predictors of HIV reservoir profile in paediatric populations. The primary outcome will be to assess the genotypical and quantitative profile of HIV reservoirs, while the secondary outcomes will be to identify factors associated with ADRMs and reservoir size in paediatric populations.Ethics and dissemination Ethical approval is not applicable for this study as it will be based on published data. Results will be disseminated via a peer-reviewed scientific journal and relevant conferences.PROSPERO registration number CRD42022327625

Filaria specific antibody response profiling in plasma from anti-retroviral naïve Loa loa microfilaraemic HIV-1 infected people

Abstract Background In West and Central Africa areas of endemic Loa loa infections overlap with regions of high prevalence of human immunodeficiency virus type 1 (HIV-1) infections. Because individuals in this region are exposed to filarial parasites from birth, most HIV-1 infected individuals invariably also have a history of filarial parasite infection. Since HIV-1 infection both depletes immune system and maintains it in perpetual inflammation, this can hamper Loa loa filarial parasite mediated immune modulation, leading to enhanced loaisis. Methods In this study we have assessed in plasma from asymptomatic anti-retroviral (ARV) naïve Loa loa microfilaraemic HIV-1 infected people the filarial antibody responses specific to a filariasis composite antigen consisting of Wbgp29-BmR1-BmM14-WbSXP. The antibody responses specific to the filariasis composite antigen was determined by enzyme linked immunosorbent assay (ELISA) in plasma from ARV naïve Loa loa microfilaraemic HIV-1 infected participants. In addition the filarial antigen specific IgG antibody subclass profiles were also determined for both HIV-1 positive and negative people. Results Both Loa loa microfilaraemic HIV-1 positive and negative individuals showed significantly higher plasma levels of IgG1 (P < 0.0001), IgG2 (P < 0.0001) and IgM (P < 0.0001) relative to amicrofilaraemic participants. A significant increase in IgE (P < 0.0001) was observed exclusively in Loa loa microfilaraemic HIV-1 infected people. In contrast there was a significant reduction in the level of IgG4 (p < 0.0001) and IgG3 (P < 0.0001) in Loa loa microfilaraemic HIV-1 infected individuals. Conclusions Loa loa microfilaraemia in ARV naïve HIV-1 infected people through differential reduction of plasma levels of filarial antigen specific IgG3, IgG4 and a significant increase in plasma levels of filarial antigen specific IgE could diminish Loa loa mediated immune-regulation. This in effect can result to increase loaisis mediated immunopathology in antiretroviral naive HIV-1 infected people