Trans cohort metabolic reprogramming towards glutaminolysis in long-term successfully treated HIV-infection

Despite successful combination antiretroviral therapy (cART), persistent low-grade immune activation together with inflammation and toxic antiretroviral drugs can lead to long-lasting metabolic flexibility and adaptation in people living with HIV (PLWH). Our study investigated alterations in the plasma metabolic profiles by comparing PLWH on long-term cART(>5 years) and matched HIV-negative controls (HC) in two cohorts from low- and middle-income countries (LMIC), Cameroon, and India, respectively, to understand the system-level dysregulation in HIV-infection. Using untargeted and targeted LC-MS/MS-based metabolic profiling and applying advanced system biology methods, an altered amino acid metabolism, more specifically to glutaminolysis in PLWH than HC were reported. A significantly lower level of neurosteroids was observed in both cohorts and could potentiate neurological impairments in PLWH. Further, modulation of cellular glutaminolysis promoted increased cell death and latency reversal in pre-monocytic HIV-1 latent cell model U1, which may be essential for the clearance of the inducible reservoir in HIV-integrated cells.

Involvement of CD95 and ligand in CD4+ T-cell and CD8+ T-cell depletion and hepatic cytolysis in patients with chronic viral hepatitis B

Background

Chronic viral hepatitis B (HBV) is characterised by progressive hepatocyte destruction and T-cell depletion. The mechanisms of the CD95-CD95 ligand (CD95L) signalling pathway during this chronic disease and the cirrhotic process remains unclear.

Objective

We evaluated the involvement of the CD95-CD95L receptor-ligand system in T-cell depletion and hepatic cytolysis in patients with chronic HBV.

Methods

This was a cross-sectional study conducted from September to December 2018 at the Yaoundé General Hospital, Cameroon. Four mL of whole blood was collected and analysed. The CD95 and CD95L levels, as well as the CD4+ T-cell and CD8+ T-cell counts, were performed by enzyme-linked immunosorbent assay and flow cytometry.

Results

Of the 130 HBV-positive patients, 36 (27.7%) were cirrhotic and 94 (72.3%) were non-cirrhotic. The cirrhotic patients had significantly elevated CD95 (p < 0.001) and CD95L (p = 0.001) plasma levels, compared with non-cirrhotic patients. The CD4/CD8 ratios were lower in cirrhotic patients, compared to non-cirrhotic patients (p < 0.001). There were statistically significant correlations between CD95 level and CD4⁺ T-cell counts, between CD95 level and CD8⁺ T-cell counts, between CD95 level and the CD4/CD8 ratio, between CD95 level and fibrosis score, and between CD95L level and fibrosis score.

Conclusion

CD95 and CD95L could be involved in T-cell depletion and hepatic cytolysis during the pathogenesis of chronic HBV and could potentially be used as biomarkers for immunological and hepatic monitoring in patients with chronic HBV.

HIV-1 Integrase Diversity and Resistance-Associated Mutations and Polymorphisms Among Integrase Strand Transfer Inhibitor-Naive HIV-1 Patients from Cameroon

The World Health Organization (WHO) has put forth recommendations for the use of integrase (IN) strand transfer inhibitors (INSTIs) to be part of the first-line combination antiretroviral therapy regimen to treat HIV infections. The knowledge of pretreatment drug resistance against INSTIs is still scarce in resource-limited settings (RLS). We characterized the integrase gene to identify resistance-associated mutations (RAMs) in 56 INSTI-naive patient viral sequences from Cameroon. Study analysis used 37 sequences with fragment size ≥500 bp or of good quality .The majority of the sequences were identified as CRF02_AG 54.% (n = 20/37) and 45.9% (n = 17/37), other subtype viral sequences include (A, CRF36_cpx, F,G, and C). A total of 18.9% (n = 7/37) of the sequences had RAMs, with only 5.4% (n = 2/37) having major RAMs (Y143R/C/D/G and P145S), against INSTIs. Accessory RAMs were present in 8.1% (n = 3/37) of the sequences, of which one sequence contained solely E157Q, and another Q95K. One patient sequence had three accessory RAMs (G140E, E157Q, and G163R). We identified major RAMs to INSTIs, which might have a potential clinical impact to dolutegravir rollout in RLS, including Cameroon. This is the first study to describe RAMs among INSTI-naive people living with HIV-1 (PLHIV-1) infected with CRF02_AG and other subtypes in Cameroon.

Rate of viral load change and adherence of HIV adult patients treated with Efavirenz or Nevirapine antiretroviral regimens at 24 and 48 weeks in Yaoundé, Cameroon: a longitudinal cohort study

Background

HIV-load decrease and suppression over time is associated with consistent adherence to antiretroviral therapy (ART). Our study aimed to evaluate the difference in viral load and adherence of patients treated with a combination of either Tenofovir (TDF), Lamivudine (3TC) and Efavirenz (EFV) or TDF / Zidovudine (AZT), 3TC and Nevirapine (NVP) regimens at 24 and 48 weeks.

Methods

A longitudinal study was conducted from May 2016 to June 2017 among 256 HIV infected adult patients who were enrolled at two approved treatment hospitals in Yaoundé, before the start of first-line ART. Whole blood samples were collected using standard operating procedures. HIV-loads were determined by a quantitative RealTime PCR assay. Adherence was evaluated by pharmacy refill data records. Statistical analyses were performed using the PRISM 5.0 software.

Results

Off the 256 HIV infected patients enrolled, 180 (70%) patients completed the study and 76 (30%) patients were lost to follow-up. The success rate in achieving viral load < 40 copies/ml was 1.8 times higher with the EFV regimen at 24 weeks and was 1.2 times higher in the NVP regimen at 48 weeks. At 48 weeks the treatment failure rate was 12.0 and 40.0% in patients on EFV and the NVP regimen, respectively. The rate of adherence varied in both ART based regimens with 84.0 to 74.0% for EFV and 65.5 to 62.5% for NVP, at 24 and 48 weeks respectively.

Conclusion

In our study and setting, the rate of viral load decrease was higher in the NVP based regimen than with the EFV regimen. The adherence rate to ART was higher in the EFV regimen, compared to the NVP regimen. This adds to evidence that the EFV regimen is the preferred ART combination for non-nucleoside reverse transcriptase inhibitors (NNRTIs).

Observed HIV drug resistance associated mutations amongst naïve immunocompetent children in Yaoundé, Cameroon

Introduction

The emergence of drug resistance mutations (DRMs) has been a major threat for successful lifelong combination antiretroviral therapy (cART), especially for HIV-vertically infected children within the context of the prevention of mother-to-child transmission (PMTCT). This study aimed to evaluate DRMs amongst immune competent treatment-naïve children in Cameroon.

Methods

A cross-sectional study was conducted between 2015 and 2016 amongst 55 proxy consented HIV-1 positive children, aged 9 months to 6 years. They were all immune competent, cART naïve and with unknown history of PMTCT. CD4 cell counts and genotypic drug resistance testing were performed using standard methods.

Results

Levels of DRMs to protease (PR) inhibitors (PIs), nucleoside reverse transcriptase inhibitors (NRTIs) and non-NRTIs were 27.6%, 3.7% and 40.7%, respectively. Only minor DRMs were observed for PR. The observed mutations for NRTI were K65R, T215I and K219E (33.0% each) and for NNRTI: V106M, Y181C and Y188H (6.0% each). Only minor accessory mutations were found in the integrase (IN) region.

Conclusion

Despite widely available cART we still observe naïve HIV children, especially from the rural communities. We observe that a proportion of study participants had HIV-1 drug resistance associated mutations (RAMs). Data generated could help strengthen the current PMTCT programmes within the country. There is a need to upscale approaches for drug resistance testing for children in Cameroon and many other resource-limited settings.

The Potentials of Fas Receptors and Ligands in Monitoring HIV-1 Disease in Children in Yaoundé, Cameroon

OBJECTIVE

Difficulties in systematically monitoring HIV viral load in resource-limited settings prompt the search for alternate approaches. The authors aimed at assessing the correlation between the plasma levels of soluble forms of Fas receptors (Fas) and Fas ligands (FasL) with standard indicators of HIV disease progression in children.

METHODS

Twenty-two HIV-1-positive children were enrolled in Yaounde. CD4 counts, CD4% counts, plasma levels of Fas, FasL, and HIV-1 RNA levels were assayed.

RESULTS

The correlation coefficients (P values) between FasL levels and each of HIV-1 viral load, CD4 counts, and CD4% were, respectively, .56 (.01), -.29 (.18), and .30 (.18). On the other hand, the respective correlation coefficients (P values) with Fas levels were .12 (.60), -.30 (.18), and -.29 (.19).

CONCLUSION

The significant correlation between levels of HIV-1 viral load and FasL suggests that the latter needs to be further studied as a potential biomarker to monitor HIV-1 disease progression in children in resource-limited setting.

Plasma concentrations of soluble Fas receptors (Fas) and Fas ligands (FasL) in relation to CD4+ cell counts in HIV-1 positive and negative patients in Yaounde, Cameroon

Background

Though documented that HIV infection progresses with the depletion of CD4+ cells, the exact mechanisms by which these cell depletions occur are not clearly understood. This study aimed at evaluating the plasma levels of soluble Fas receptors and ligands in HIV-infected and uninfected patients in Yaounde, Cameroon, a population with a known diversity of HIV in whom this has not been previously assessed.

Findings

In a cross-sectional study, 39 antiretroviral naïve HIV-1 positive and negative participants were recruited in Yaounde, Cameroon. CD4+ lymphocyte cell counts were quantified from whole blood using an automated FACScount machine (Becton-Dickinson, Belgium). Plasma samples obtained were analyzed for soluble Fas receptors and Fas ligands in both HIV-1 positive and negative samples using two different quantitative sandwich ELISA kits (Quantikine®, R&D Systems , UK).

Plasma levels of Fas receptors were higher in HIV-1 positive patients (median = 1486pg/ml IQR = 1193, 1830pg/ml) compared to HIV-negative controls (median = 1244pg/ml, IQR = 1109, 1325pg/ml), p-value <0.001. Plasma levels of Fas ligands were also higher in HIV-1 positive patients (median = 154pg/ml, IQR = 111, 203pg/ml) compared to HIV-negative controls (median = 51pg/ml, IQR = 32, 88pg/ml), p-value = 0.005. Plasma concentrations of soluble fas receptors and ligands tended to be negatively correlated with the CD4+ cell counts of HIV-positive patients; the correlation coefficients were -0.34 (value = 0.78) and-0.3 (p-value = 0.51) respectively.

Conclusions

In this population of patients in Cameroon, plasma concentrations of Fas receptors and Fas ligands tend to be higher in HIV-positive patients. The Fas pathway of apoptosis may have a role in the depletion of CD4+ cell counts