Corrigendum: CD4/CD8 ratio and CD8+ T-cell count as prognostic markers for non-AIDS mortality in people living with HIV. A systematic review and meta-analysis.

[This corrects the article DOI: 10.3389/fimmu.2024.1343124.].

CD4/CD8 ratio and CD8+ T-cell count as prognostic markers for non-AIDS mortality in people living with HIV. A systematic review and meta-analysis.

Background: In people living with HIV (PLHIV), the CD4/CD8 ratio has been proposed as a useful marker for non-AIDS events. However, its predictive ability on mortality over CD4 counts, and the role of CD8+ T-cell counts remain controversial. Methods: We conducted a systematic review and meta-analysis of published studies from 1996 to 2023, including PLHIV on antiretroviral treatment, and reporting CD4/CD8 ratio or CD8+ counts. The primary outcome was non-AIDS mortality or all-cause mortality. We performed a standard random-effects pairwise meta-analysis comparing low versus high CD4/CD8 ratio with a predefined cut-off point of 0.5. (CRD42020170931). Findings: We identified 2,479 studies for screening. 20 studies were included in the systematic review. Seven studies found an association between low CD4/CD8 ratio categories and increased mortality risk, with variable cut-off points between 0.4-1. Four studies were selected for meta-analysis, including 12,893 participants and 618 reported deaths. Patients with values of CD4/CD8 ratio below 0.5 showed a higher mortality risk (OR 3.65; 95% CI 3.04 - 4.35; I2 = 0.00%) compared to those with higher values. While the meta-analysis of CD8+ T-cell counts was not feasible due to methodological differences between studies, the systematic review suggests a negative prognostic impact of higher values (>1,138 to 1,500 cells/uL) in the long term. Conclusions: Our results support the use of the CD4/CD8 ratio as a prognostic marker in clinical practice, especially in patients with values below 0.5, but consensus criteria on ratio timing measurement, cut-off values, and time to event are needed in future studies to get more robust conclusions. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020170931, identifier CRD42020170931.

The microbiome as a biomarker of anal precancerous lesions in people with HIV.

PURPOSE OF REVIEW: Early detection and treatment of human papillomavirus (HPV)-related anal dysplasia in some high-risk groups can help anal cancer prevention, but new tools to improve diagnostic and risk assessment are needed. Here, we aim to discuss the evidence on the role of the microbiome as a potential biomarker for anal high-grade squamous intraepithelial lesions (HSILs) in people with HIV (PWH). RECENT FINDINGS: This review covers relevant studies on the links between the microbiome and HPV infection, cervical dysplasia/cancer, and anal HPV disease. It focuses on anal samples and precancerous lesions. SUMMARY: The review highlights the promising potential of the anal microbiome as a novel biomarker for precancerous lesions in people with HIV, while also discussing limitations and future research needs.

Knowledge, attitudes and practices in HIV-related chronic inflammation and cardiovascular risk in Spain.

BACKGROUND: People with HIV (PWH) in suppressive antiretroviral treatment suffer from chronic inflammation-related comorbidities, mainly cardiovascular diseases. However, given the lack of specific evidence about inflammation in PWH, clinical guidelines do not provide recommendations for the management of this issue. To date, physician awareness of inflammation in PWH remains unclear. We analyzed the knowledge, attitudes, and practices (KAP) related to inflammation, particularly in the clinical management of PWH, of infectious disease specialists (IDS)/internists compared to other specialists treating inflammation directly (rheumatologists) or its cardiovascular consequences (cardiologists). METHODS: A committee of IDS/internists treating PWH, cardiologists, and rheumatologists designed the KAP questionnaire. The survey was completed by 405 participants (135 physicians per specialty) stratified by Spanish geography, hospital size, and number of PWH under care (IDS/internists only). RESULTS: IDS/internists treating PWH scored higher than cardiologists and rheumatologists on knowledge of inflammation (5.5±1.4 out of 8 points vs. 5.2±1.3 and 4.6±1.4 points, respectively; p<0.05). Nevertheless, rheumatologists showed the most proactive attitude toward inflammation (i.e., biomarkers monitoring, anti-inflammatory drug prescription and cardiologist referral), followed by cardiologists and IDS/internists (13±3 of a total of 16 points vs. 11±3 and 10±3.3 points, respectively; p<0.05), irrespective of hospital size and years of experience. Most IDS/internists (59%) include inflammation in their therapeutic recommendations. However, in IDS/internists treating PWH, we observed a negative correlation between years of experience and concern about the clinical consequences of inflammation. CONCLUSION: Our findings show that, compared to other specialists, infectious disease specialists/internists have high knowledge about inflammation in HIV infection, but, in the absence of scientific evidence to base their decisions on inflammatory markers, the therapeutic implications are scarce. The results support the need for more evidence on the monitoring and treatment of inflammation in PWH.

Prevalence, characteristics, and associated risk factors of drug consumption and chemsex use among individuals attending an STI clinic (EpITs STUDY).

Sex-related drug consumption and its health-related consequences have gained relevance in the assessment of patients with sexually transmitted infections (STIs), which pose a significant challenge to public health. We aim to assess the prevalence and characteristics of drug consumption and chemsex practices, describe the associated risk factors among general individuals attending an STI clinic, and evaluate the psychological impact associated with these behaviors. We conducted an online anonymous survey offered to patients with a diagnosis of STI in a tertiary hospital in Spain. Data included sociodemographic characteristics, sexual preferences and behavior, and assessment of drug use, chemsex, and psychological and mental health symptoms. Data from 145 subjects was collected, with a higher proportion of cis-gender men (71%), and a median age of 32 years. 64 participants (44%) reported drug use in the last year, with an observed 33.8% prevalence of chemsex consumption. Drug use and chemsex were more frequent among cis-gender men, Men who have Sex with Men (MSM), people living with HIV (PLHIV), and those reporting previous group sex. Poppers and cannabis were the most frequently reported drugs, with a prevalence close to 20% for cocaine, mephedrone, extasis, and GHB. Consequences related to drug use included unpleasant physical sensations, sexual dysfunction, and impaired sexual experience after reduction or drug discontinuation. The prevalence of drug use and chemsex practices are high among patients evaluated for STIs, especially between men, MSM, and subjects practicing group sex. The study highlights the urgent need for targeted interventions on prevention and reduction of their impact on health and social well-being.

Differential abundance of lipids and metabolites related to SARS-CoV-2 infection and susceptibility.

The mechanisms driving SARS-CoV-2 susceptibility remain poorly understood, especially the factors determining why unvaccinated individuals remain uninfected despite high-risk exposures. To understand lipid and metabolite profiles related with COVID-19 susceptibility and disease progression. We collected samples from an exceptional group of unvaccinated healthcare workers heavily exposed to SARS-CoV-2 but not infected ('non-susceptible') and subjects who became infected during the follow-up ('susceptible'), including non-hospitalized and hospitalized patients with different disease severity providing samples at early disease stages. Then, we analyzed their plasma metabolomic profiles using mass spectrometry coupled with liquid and gas chromatography. We show specific lipids profiles and metabolites that could explain SARS-CoV-2 susceptibility and COVID-19 severity. More importantly, non-susceptible individuals show a unique lipidomic pattern characterized by the upregulation of most lipids, especially ceramides and sphingomyelin, which could be interpreted as markers of low susceptibility to SARS-CoV-2 infection. This study strengthens the findings of other researchers about the importance of studying lipid profiles as relevant markers of SARS-CoV-2 pathogenesis.

Global DNA methylation and telomere length as markers of accelerated aging in people living with HIV and non-alcoholic fatty liver disease.

Metabolic-dysfunction-associated fatty liver disease (MAFLD) is a comorbidity that generally increases in people living with HIV (PLWH). This condition is usually accompanied by persistent inflammation and premature immune system aging. In this prospective cohort study, we describe a straightforward methodology for quantifying biomarkers of aging, such as DNA methylation and telomere length, in PLWH and in the context of another relevant condition, such as MAFLD. Fifty-seven samples in total, thirty-eight from PLWH and nineteen from non-PLWH participants with or without MAFLD, were obtained and subjected to DNA extraction from peripheral blood mononuclear cells (PBMCs). Global DNA methylation and telomere length quantification were performed using an adapted enzyme-linked immunosorbent assay (ELISA) and qPCR, respectively. The quantification results were analysed and corrected by clinically relevant variables in this context, such as age, sex, and metabolic syndrome. Our results show an increased association of these biomarkers in PLWH regardless of their MAFLD status. Thus, we propose including the quantification of these age-related factors in studies of comorbidities. This will allow a better understanding of the effect of comorbidities of HIV infection and MAFLD and prevent their effects in these populations in the future.

Expanding HIV clinical monitoring: the role of CD4, CD8, and CD4/CD8 ratio in predicting non-AIDS events.

BACKGROUND: While a low CD4/CD8 ratio during HIV treatment correlates with immunosenescence, its value in identifying patients at an increased risk for clinical events remains unclear. METHODS: We analyzed data from the CoRIS cohort to determine whether CD4 count, CD8 count, and CD4/CD8 ratio at year two of antiretroviral therapy (ART) could predict the risk of serious non-AIDS events (SNAEs) during the next five years. These included major adverse cardiovascular events, non-AIDS-defining malignancies, and non-accidental deaths. We used pooled logistic regression with inverse probability weighting to estimate the survival curves and cumulative risk of clinical events. FINDINGS: The study included 4625 participants, 83% male, of whom 200 (4.3%) experienced an SNAE during the follow-up period. A CD4/CD8 ratio <0.3 predicted an increased risk of SNAEs during the next five years (OR 1.63, 95% CI 1.03-2.58). The effect was stronger at a CD4/CD8 ratio cut-off of <0.2 (OR 3.09, 95% CI 1.57-6.07). Additionally, low CD4 count at cut-offs of <500 cells/µL predicted an increased risk of clinical events. Among participants with a CD4 count ≥500 cells/µL, a CD8 count ≥1500 cells/µL or a CD4/CD8 ratio <0.4 predicted increased SNAE risk. INTERPRETATION: Our results support the use of the CD4/CD8 ratio and CD8 count as predictors of clinical progression. Patients with CD4/CD8 ratio <0.3 or CD8 count ≥1500/µL, regardless of their CD4 count, may benefit from closer monitoring and targeted preventive interventions. FUNDING: This work was supported by CIBER (CB 2021), Instituto de Salud Carlos III, Ministerio de Ciencia e Innovación and Unión Europea-NextGenerationEU; by the Spanish AIDS Research Network (RIS) RD16/0025/0001 project as part of the Plan Nacional R + D + I, and cofinanced by Instituto de Salud Carlos III (ISCIII)- Subdirección General de Evaluación y el Fondo Europeo de Desarrollo Regional (FEDER), ISCIII projects PI18/00154, PI21/00141, and ERDF, "A way to make Europe", ICI20/00058.

Microbiome-derived cobalamin and succinyl-CoA as biomarkers for improved screening of anal cancer.

Human papillomavirus can cause preinvasive, high-grade squamous intraepithelial lesions (HSILs) as precursors to cancer in the anogenital area, and the microbiome is suggested to be a contributing factor. Men who have sex with men (MSM) living with human immunodeficiency virus (HIV) have a high risk of anal cancer, but current screening strategies for HSIL detection lack specificity. Here, we investigated the anal microbiome to improve HSIL screening. We enrolled participants living with HIV, divided into a discovery (n = 167) and validation cohort (n = 46), and who were predominantly (93.9%) cisgender MSM undergoing HSIL screening with high-resolution anoscopy and anal biopsies. We identified no microbiome composition signatures associated with HSILs, but elevated levels of microbiome-encoded proteins producing succinyl coenzyme A and cobalamin were significantly associated with HSILs in both cohorts. Measurement of these candidate biomarkers alone in anal cytobrushes outperformed anal cytology as a diagnostic indicator for HSILs, increasing the sensitivity from 91.2% to 96.6%, the specificity from 34.1% to 81.8%, and reclassifying 82% of false-positive results as true negatives. We propose that these two microbiome-derived biomarkers may improve the current strategy of anal cancer screening.

From Innovation to Implementation: The Evolution of HIV Pre-Exposure Prophylaxis and Future Implications.

Pre-exposure prophylaxis (PrEP) is a highly effective HIV-prevention strategy that involves the continuous administration of antiretroviral drugs to HIV-negative individuals with a substantial risk of contracting an HIV infection. The use of PrEP has shown a reduction in the risk of HIV acquisition through sexual intercourse by up to 99%. Despite its effectiveness, PrEP uptake remains low among populations at high risk of HIV infection. This highlights the need for further research in strategies to enhance awareness and uptake of PrEP amongst these specific populations. This article presents a comprehensive overview of the existing literature on the effectiveness of PrEP in reducing HIV transmission rates. Additionally, we examine the obstacles related to PrEP implementation and uptake and put forward potential strategies to raise awareness and improve its use among populations at an increased risk of contracting HIV.

Chagas disease is related to structural changes of the gut microbiota in adults with chronic infection (TRIPOBIOME Study).

BACKGROUND: The implications of the gut microbial communities in the immune response against parasites and gut motility could explain the differences in clinical manifestations and treatment responses found in patients with chronic Chagas disease. METHODOLOGY/PRINCIPAL FINDINGS: In this pilot prospective cross-sectional study, we included 80 participants: 29 with indeterminate CD (ICD), 16 with cardiac CD (CCD), 15 with digestive CD (DCD), and 20 controls without CD. Stool was collected at the baseline visit and faecal microbial community structure DNA was analyzed by whole genome sequencing. We also performed a comprehensive dietary analysis. Ninety per cent (72/80) of subjects were of Bolivian origin with a median age of 47 years (IQR 39-54) and 48.3% (29/60) had received benznidazole treatment. There were no substantial differences in dietary habits between patients with CD and controls. We identified that the presence or absence of CD explained 5% of the observed microbiota variability. Subjects with CD exhibited consistent enrichment of Parabacteroides spp, while for Enterococcus hirae, Lactobacillus buchneri and Megamonas spp, the effect was less clear once excluded the outliers values. Sex, type of visceral involvement and previous treatment with benznidazole did not appear to have a confounding effect on gut microbiota structure. We also found that patients with DCD showed consistent Prevotella spp enrichment. CONCLUSIONS: We found a detectable effect of Chagas disease on overall microbiota structure with several potential disease biomarkers, which warrants further research in this field. The analysis of bacterial diversity could prove to be a viable target to improve the prognosis of this prevalent and neglected disease.

Beyond Undetectable: Modeling the Clinical Benefit of Improved Antiretroviral Adherence in Persons With Human Immunodeficiency Virus With Virologic Suppression.

Background: Incomplete antiretroviral therapy (ART) adherence has been linked to deleterious immunologic, inflammatory, and clinical consequences, even among virally suppressed (<50 copies/mL) persons with human immunodeficiency virus (PWH). The impact of improving adherence in the risk of severe non-AIDS events (SNAEs) and death in this population is unknown. Methods: We estimated the reduction in the risk of SNAEs or death resulting from an increase in ART adherence by (1) applying existing data on the association between adherence with high residual inflammation/coagulopathy in virally suppressed PWH, and (2) using a Cox proportional hazards model derived from changes in plasma interleukin 6 (IL-6) and D-dimer from 3 randomized clinical trials. Comparatively, assuming 100% ART adherence in a PWH who achieves viral suppression, we estimated the number of persons in whom a decrease in adherence to <100% would need to be observed for an additional SNAE or death event to occur during 3- and 5-year follow-up. Results: Increasing ART adherence to 100% in PWH who are suppressed on ART despite imperfect adherence translated into a 6%-37% reduction in the risk of SNAEs or death. Comparatively, based on an anticipated 12% increase in IL-6, 254 and 165 PWH would need to decrease their adherence from 100% to <100% for an additional event to occur over 3- and 5-year follow-up, respectively. Conclusions: Modest gains in ART adherence could have clinical benefits beyond virologic suppression. Increasing ART adherence (eg, via an intervention or switch to long-acting ART) in PWH who remain virally suppressed despite incomplete adherence should be evaluated.

Diversity of immune responses in children highly exposed to SARS-CoV-2.

Background: Children are less susceptible than adults to symptomatic COVID-19 infection, but very few studies addressed their underlying cause. Moreover, very few studies analyzed why children highly exposed to the virus remain uninfected. Methods: We analyzed the serum levels of ACE2, angiotensin II, anti-spike and anti-N antibodies, cytokine profiles, and virus neutralization in a cohort of children at high risk of viral exposure, cohabiting with infected close relatives during the lockdown in Spain. Results: We analyzed 40 children who were highly exposed to the virus since they lived with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)-infected relatives during the lockdown for several months without taking preventive measures. Of those, 26 reported mild or very mild symptoms. The induced immune response to the virus was analyzed 3 months after the household infection. Surprisingly, only 15 children had IgG anti-S (IgG+) determined by a sensitive method indicative of a past infection. The rest, negative for IgG anti-N or S in various tests, could be further subdivided, according to IgM antibodies, into those having IgM anti-S and IgM anti-N (IgG-IgMhigh) and those having only IgM anti-N (IgG-IgMlow). Interestingly, those two subgroups of children with IgM antibodies have strikingly different patterns of cytokines. The IgMhigh group had significantly higher IFN-α2 and IFN-γ levels as well as IL-10 and GM-CSF than the IgMlow group. In contrast, the IgMlow group had low levels of ACE2 in the serum. Both groups have a weaker but significant capacity to neutralize the virus in the serum than the IgG+ group. Two children were negative in all immunological antibody tests. Conclusions: A significant proportion of children highly exposed to SARS-CoV-2 did not develop a classical adaptive immune response, defined by the production of IgG, despite being in close contact with infected relatives. A large proportion of those children show immunological signs compatible with innate immune responses (as secretion of natural antibodies and cytokines), and others displayed very low levels of the viral receptor ACE2 that may have protected them from the virus spreading in the body despite high and constant viral exposure.

Corrigendum: Translating the observed differences in interleukin-6 levels between some antiretroviral regimens into potential long-term risk of serious non-AIDS events: A modeling study.

[This corrects the article DOI: 10.3389/fimmu.2022.976564.].

Contribution of Low CD4 Cell Counts and High Human Immunodeficiency Virus (HIV) Viral Load to the Efficacy of Preferred First-Line Antiretroviral Regimens for Treating HIV Infection: A Systematic Review and Meta-Analysis.

We assessed whether low CD4 count and high viral load (VL) affect the response to currently preferred ART. We performed a systematic review of randomized, controlled clinical trials that analyzed preferred first-line ART and a subgroup analysis by CD4 count (≤ or >200 CD4/µL) or VL (≤ or >100 000 copies/mL). We computed the odds ratio (OR) of treatment failure (TF) for each subgroup and individual treatment arm. Patients with ≤200 CD4 cells or VL ≥100 000 copies/mL showed an increased likelihood of TF at 48 weeks: OR, 1.94; 95% confidence interval (CI): 1.45-2.61 and OR, 1.75; 95% CI: 1.30-2.35, respectively. A similar increase in the risk of TF was observed at 96 weeks. There was no significant heterogeneity regarding integrase strand transfer inhibitor or nucleoside reverse transcriptase inhibitor backbone. Our results show that CD4 <200 cells/µL and VL ≥100,000 copies/mL impair ART efficacy in all preferred regimens.

CD4/CD8 Ratio During Human Immunodeficiency Virus Treatment: Time for Routine Monitoring?

In the last decade, studies in persons with HIV (PWH) on antiretroviral therapy (ART) have shed light on the significance of persistently high CD8 counts and low CD4/CD8 ratios. A low CD4/CD8 ratio reflects increased immune activation and is associated with an increased risk of severe non-AIDS events. As a result, many clinicians now believe that the CD4/CD8 ratio can help in HIV monitoring, and many researchers now report it as an efficacy marker in interventional studies. However, the topic is more complex. Recent studies have not yielded unanimous conclusions on the ability of the CD4/CD8 ratio to predict adverse outcomes, and only some clinical guidelines recommend monitoring it. Knowledge gaps remain on the best cutoff points, associated clinical events, effects of treatments, and how the CD4/CD8 ratio could improve decision making in the clinic. Here, we critically review the literature, identify knowledge gaps, and discuss the role of the CD4/CD8 ratio as a marker for HIV monitoring.

The microbiota as a modulator of mucosal inflammation and HIV/HPV pathogenesis: From association to causation.

Although the microbiota has largely been associated with the pathogenesis of viral infections, most studies using omics techniques are correlational and hypothesis-generating. The mechanisms affecting the immune responses to viral infections are still being fully understood. Here we focus on the two most important sexually transmitted persistent viruses, HPV and HIV. Sophisticated omics techniques are boosting our ability to understand microbiota-pathogen-host interactions from a functional perspective by surveying the host and bacterial protein and metabolite production using systems biology approaches. However, while these strategies have allowed describing interaction networks to identify potential novel microbiota-associated biomarkers or therapeutic targets to prevent or treat infectious diseases, the analyses are typically based on highly dimensional datasets -thousands of features in small cohorts of patients-. As a result, we are far from getting to their clinical use. Here we provide a broad overview of how the microbiota influences the immune responses to HIV and HPV disease. Furthermore, we highlight experimental approaches to understand better the microbiota-host-virus interactions that might increase our potential to identify biomarkers and therapeutic agents with clinical applications.