Immunologic and virologic parameters associated with HIV DNA reservoir size in people living with HIV receiving antiretroviral therapy

BACKGROUND

A better understanding of the dynamics of HIV reservoirs in CD4+ T cells of people with HIV (PWH) receiving antiretroviral therapy (ART) is crucial for developing therapies to eradicate the virus.

METHODS

We conducted a study involving 28 aviremic PWH receiving ART with high and low levels of HIV DNA. We analyzed immunologic and virologic parameters and their association with the HIV reservoir size.

RESULTS

The frequency of CD4+ T cells carrying HIV DNA was associated with higher pre-ART plasma viremia, lower pre-ART CD4+ T cell counts, and lower pre-ART CD4/CD8 ratios. During ART, the High group maintained elevated levels of intact HIV proviral DNA, cell-associated HIV RNA, and inducible virion-associated HIV RNA. HIV sequence analysis showed no evidence for preferential accumulation of defective proviruses nor higher frequencies of clonal expansion in the High versus Low group. Phenotypic and functional T-cell analyses did not show enhanced immune-mediated virologic control in the Low versus High group. Of considerable interest, pre-ART innate immunity was significantly higher in the Low versus High group.

CONCLUSIONS

Our data suggest that innate immunity at the time of ART initiation may play an important role in modulating the dynamics and persistence of viral reservoirs in PWH.

Immuno-virological status and its associated factors among HIV-positive patients receiving highly active antiretroviral therapy at delgi primary hospital, northwest Ethiopia, 2020/2021: A cross-sectional study

Background

Highly active antiretroviral therapy (HAART) improves clinical outcomes by suppressing viral replication and allowing immune reconstitution. It also reduces HIV-related complications including morbidity, mortality, and extended hospitalizations for HIV-positive individuals. Regular assessment for antiretroviral treatment response is fundamentally important to address the factors associated with the poor clinical outcome including immunologic failures among HIV-positive patients on HAART. Therefore, this study aimed to investigate the immuno-virological status and describe its determinants among HIV-positive patients receiving HAART at Delgi primary hospital, Northwest Ethiopia.

Methods

A hospital-based cross-sectional study was conducted at Delgi primary hospital from October 25th through June 19th 2021 among a total of 442 study participants. A systematic random sampling technique was employed to enrol participants in the study. Socio-demographic and clinically related data were collected using a semi-structured questionnaire. About 3–5 ml of venous blood was collected aseptically for CD4⁺ T cell count and viral load test. SPSS version 20 software was used for statistical analysis. Bivariate and multivariate logistic regression analyses were conducted to determine the factors associated with immuno-virologic status among HIV-positive patients on HAART. The odds ratio with 95% CI was computed to determine the strength of association. Then, a p-value < 0.05 was considered a statistically significant association. For this study, the results were presented by using frequency summary tables, and texts.

Results

Among the total study participants, 283 (64%) were males and the mean age of the study participants was 37 ± 11.5. The overall immunological and virological failure among highly active antiretroviral therapy (HAART) receiving participants was found to be 9.5% (42/442, 95%CI:3.23–15.09) and 12.2% (54/442, 95% CI: 2.81–23.04) respectively. In the multivariate analysis, study participants with age ≥50 years old [AOR = 1.97, p = 0.01, 95%CI (0.02–4.03)], participants having current viral load count greater ≥1000 copies/ml [AOR = 3.97, p = 0.03, 95%CI (1.09–5.01)] and having TB-co-infection [AOR = 2.51, p = 0.05, 95%CI (1.02–7.51)] were statistically associated with increased risk of immunological failure. Similarly, TB-coinfected participants were 1.88 (95%CI = 0.89–10.02) times at greater risk for virological failure.

Conclusion

In this study, the magnitude of immuno-virological failure is alarming. This may be shown the need for integrated and substantial commitment to enhancing patient antiretroviral treatment adherence in the study area. Also, regular assessment for antiretroviral treatment response is fundamentally important to address the determinants associated with virological and immunologic failures among HIV-positive patients taking HAART. Furthermore, early initiation of HAART may be imperative to achieve favourable virological suppression and immunological reconstitution.

T-Bet Expression Mediated by the mTOR Pathway Influences CD4+ T Cell Count in Mice With Lethal Candida Sepsis

The sustained high morbidity and mortality of Candida sepsis are mainly caused by compromise of host immunity. Clinically, it is often manifested as a significant decrease in CD4+ T cell count, although the mechanism is unclear. We established a lethal mice Candida sepsis model and used Murine Sepsis Score to group mice with different disease severity to establish the influence of T-bet expression on CD4+ T cell count in Candida sepsis. We found that CD4+ T cell count decreased in Candida-infected compared to uninfected mice, and the degree of decrease increased with aggravation of sepsis. Expression of T-bet similarly decreased with worsening of sepsis, but it was significantly enhanced in candidiasis in comparison of naïve state. To clarify its possible mechanism, we measured the activity of mammalian target of rapamycin (mTOR), which is a key regulator of T-bet expression. The mTOR pathway was activated after infection and its activity increased with progression of sepsis. We used mice with T-cell-specific knockout of mTOR or tuberous sclerosis complex (TSC)1 to further inhibit or strengthen the mTOR signaling pathway. We found that mTOR deletion mice had a higher CD4+ T cell count by regulating T-bet expression, and the result in TSC1 deletion mice was reversed. These results demonstrate that T-bet expression mediated by the mTOR pathway influences the CD4+ T cell count in mice with Candida sepsis.

Cryptosporidium infection among people living with HIV/AIDS in Ethiopia: a systematic review and meta-analysis

Studies on the prevalence of Cryptosporidium infection in People Living with HIV/AIDS (PLWHA) are inconsistent and heterogeneous. Therefore, this systematic review with meta-analysis was performed to assess the burden of the infection relative to the proportion of CD4 + T cell count among PLWHA in Ethiopia. Articles published before 15 May 2019, have been retrieved for this systematic review using five databases; PubMed, Scopus, Web of Science, Google Scholar and ProQuest, supplemented by the search for gray literature. The overall pooled prevalence and pooled Odds Ratio (OR) with their 95% Confidence Intervals (CI) were estimated using STATA 14 statistical Software. Of the 255 studies retrieved, 31 were considered for the final analysis. As many as 8,645 Ethiopians infected with HIV were included in the final quantitative synthesis. The overall pooled prevalence estimate of Cryptosporidium infection among PLWHA in Ethiopia was 11% (95%CI: 0.09-0.13). HIV-infected people with low CD4 + T cell count (CD4 < 200 cells/mm3) were 13.07 times more likely to become infected with Cryptosporidium than those with high CD4 + T cell count (CD4 > 500 cells/mm3) (OR: 13.07 (95%CI: 6.38-26.75). Cryptosporidium infection in PLWHA in Ethiopia showed decreasing patterns in 2001-2010, 2011-2014, and in 2015-2019, 14.6% (95%CI: 0.076-0.217), 12.71% (95%CI: 0.086-0.167) and 6.7% (95%CI: 0.044-0.090), respectively (p < 0.001). Though the pattern of Cryptosporidium infection in HIV-infected Ethiopians showed a declining trend; it remains a considerable problem that requires improvement in routine screening for Cryptosporidium in HIV-infected people, particularly with poor or declining CD4 + T cell count.

Associations of gender and serum total cholesterol with CD4+ T cell count and HIV RNA load in antiretroviral-naïve individuals in Addis Ababa

Background

Males are more susceptible than females to infections due to the differences in endocrine-immune interactions. Furthermore, it is reported that lowering cell cholesterol impairs viral replication and infection in vitro. However, the production of oxysterols in vivo by oxidation of cholesterol may result in inhibition of HIV replication. Therefore, this study was designed to determine the associations of gender and serum total cholesterol with CD4+ T cell counts and/or WHO clinical stages, and HIV ribonucleic acid (RNA) load in antiretroviral therapy (ART) naive study population with known sero-positive time of stay in Addis Ababa. 

Methods

A cross-sectional study was conducted from February to August 2013 on 594 HIV-1 infected ART-naïve adult study participants in four hospitals Addis Ababa. CD4+ T-cell count, HIV RNA load, hemoglobin and fasting serum total cholesterol were determined. Socio-demographic characteristics, WHO clinical stages, and height and weight were collected from patients’ chart and triangulated by structured questionnaire. Pearson chi-square test, Spearman rank correlation and univariate and multivariate linear/logistic regression analyses were carried out to determine associations.

Results

Mean HIV RNA load was found to be lower in women than in men (p < 0.05). CD4+ T cell count and serum total cholesterol were found to be significantly correlated with HIV RNA load (p < 0.01). Women were at lower risk of having higher HIV RNA load in comparison to men. In addition, having lower concentrations of serum total cholesterol was found to be independent predictor of higher HIV RNA load in comparison to those with higher concentrations of cholesterol in serum (p < 0.05). The multivariate binomial logistic regression also showed that the immune status was better in women than men, and in the presence of higher serum total cholesterol (p < 0.05).

Conclusion

Gender and serum total cholesterol were found to be associated and independent predictors of HIV RNA load, and CD4+ cell count and/or WHO clinical stages. There is a significant lower HIV RNA load and better CD4+ T cell count in women and those study participants with higher serum total cholesterol.

Electronic supplementary material

The online version of this article (10.1186/s12889-018-5852-4) contains supplementary material, which is available to authorized users.

Caffeine and Insomnia in People Living With HIV From the Miami Adult Studies on HIV (MASH) Cohort

We explored the relationship between caffeine consumption, insomnia, and HIV disease progression (CD4+ T cell counts and HIV viral loads). Caffeine intake and insomnia levels were measured using the Modified Caffeine Consumption Questionnaire and the Pittsburgh Insomnia Rating Scale (PIRS) in 130 clinically stable participants who were living with HIV, taking antiretroviral therapy, and recruited from the Miami Adult Studies on HIV cohort. Linear regressions showed that caffeine consumption was significantly and adversely associated with distress score, quality-of-life score, and global PIRS score. Linear regression analyses also showed that global PIRS score was significantly associated with lower CD4+ T cell counts and higher HIV viral loads. Caffeine could have precipitated insomnia in susceptible people living with HIV, which could be detrimental to their disease progression states.

Impact of early treatment programs on HIV epidemics: An immunity-based mathematical model

While studies on pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP) have demonstrated substantial advantages in controlling HIV transmission, the overall benefits of the programs with early initiation of antiretroviral therapy (ART) have not been fully understood and are still on debate. Here, we develop an immunity-based (CD4+ T cell count based) mathematical model to study the impacts of early treatment programs on HIV epidemics and the overall community-level immunity. The model is parametrized using the HIV prevalence data from South Africa and fully analyzed for stability of equilibria and infection persistence criteria. Using our model, we evaluate the effects of early treatment on the new infection transmission, disease death, basic reproduction number, HIV prevalence, and the community-level immunity. Our model predicts that the programs with early treatments significantly reduce the new infection transmission and increase the community-level immunity, but the treatments alone may not be enough to eliminate HIV epidemics. These findings, including the community-level immunity, might provide helpful information for proper implementation of HIV treatment programs.