SHIV-C109p5 NHP induces rapid disease progression in elderly macaques with extensive GI viral replication.

CCR5-tropic simian/human immunodeficiency viruses (SHIV) with clade C transmitted/founder envelopes represent a critical tool for the investigation of HIV experimental vaccines and microbicides in nonhuman primates, although many such isolates lead to spontaneous viral control post infection. Here, we generated a high-titer stock of pathogenic SHIV-C109p5 by serial passage in two rhesus macaques (RM) and tested its virulence in aged monkeys. The co-receptor usage was confirmed before infecting five geriatric rhesus macaques (four female and one male). Plasma viral loads were monitored by reverse transcriptase-quantitative PCR (RT-qPCR), cytokines by multiplex analysis, and biomarkers of gastrointestinal damage by enzyme-linked immunosorbent assay. Antibodies and cell-mediated responses were also measured. Viral dissemination into tissues was determined by RNAscope. Intravenous SHIV-C109p5 infection of aged RMs leads to high plasma viremia and rapid disease progression; rapid decrease in CD4+ T cells, CD4+CD8+ T cells, and plasmacytoid dendritic cells; and wasting necessitating euthanasia between 3 and 12 weeks post infection. Virus-specific cellular immune responses were detected only in the two monkeys that survived 4 weeks post infection. These were Gag-specific TNFα+CD8+, MIP1ß+CD4+, Env-specific IFN-γ+CD4+, and CD107a+ T cell responses. Four out of five monkeys had elevated intestinal fatty acid binding protein levels at the viral peak, while regenerating islet-derived protein 3α showed marked increases at later time points in the three animals surviving the longest, suggesting gut antimicrobial peptide production in response to microbial translocation post infection. Plasma levels of monocyte chemoattractant protein-1, interleukin-15, and interleukin-12/23 were also elevated. Viral replication in gut and secondary lymphoid tissues was extensive.IMPORTANCESimian/human immunodeficiency viruses (SHIV) are important reagents to study prevention of virus acquisition in nonhuman primate models of HIV infection, especially those representing transmitted/founder (T/F) viruses. However, many R5-tropic SHIV have limited fitness in vivo leading to many monkeys spontaneously controlling the virus post acute infection. Here, we report the generation of a pathogenic SHIV clade C T/F stock by in vivo passage leading to sustained viral load set points, a necessity to study pathogenicity. Unexpectedly, administration of this SHIV to elderly rhesus macaques led to extensive viral replication and fast disease progression, despite maintenance of a strict R5 tropism. Such age-dependent rapid disease progression had previously been reported for simian immunodeficiency virus but not for R5-tropic SHIV infections.

Statistical process control of manufacturing tablets for antiretroviral therapy

Abstract In this study, the manufacturing process of lamivudine (3TC) and zidovudine (AZT) tablets (150+300 mg respectively) was evaluated using statistical process control (SPC) tools. These medicines are manufactured by the Fundação para o Remédio Popular "Chopin Tavares de Lima" (FURP) laboratory, and are distributed free of charge to patients infected with HIV by the Ministry of Health DST/AIDS national program. Data of 529 batches manufactured from 2012 to 2015 were collected. The critical quality attributes of weight variation, uniformity of dosage units, and dissolution were evaluated. Process stability was assessed using control charts, and the capability indices Cp, Cpk, Pp, and Ppk (process capability; process capability adjusted for non-centered distribution; potential or global capability of the process; and potential process capability adjusted for non-centered distribution, respectively) were evaluated. 3TC dissolution data from 2013 revealed a non-centered process and lack of consistency compared to the other years, showing Cpk and Ppk lower than 1.0 and the chance of failure of 2,483 in 1,000,000 tablets. Dissolution data from 2015 showed process improvement, revealed by Cpk and Ppk equal to 2.19 and 1.99, respectively. Overall, the control charts and capability indices showed the variability of the process and special causes. Additionally, it was possible to point out the opportunities for process changes, which are fundamental for understanding and supporting a continuous improvement environment.

Interventions to increase early infant diagnosis of HIV infection: A systematic review and meta-analysis.

OBJECTIVES: Early infant diagnosis (EID) of HIV infection increases antiretroviral therapy initiation, which reduces pediatric HIV-related morbidity and mortality. This review aims to critically appraise the effects of interventions to increase uptake of early infant diagnosis. DESIGN: This is a systematic review and meta-analysis of interventions to increase the EID of HIV infection. We searched PubMed, EMBASE, CINAHL, and PsycINFO to identify eligible studies from inception of these databases to June 18, 2020. EID Uptake at 4-8 weeks of age was primary outcome assessed by the review. We conducted meta-analysis, using data from reports of included studies. The measure of the effect of dichotomous data was odds ratios (OR), with a 95% confidence interval. The grading of recommendations assessment, development, and evaluation (GRADE) approach was used to assess quality of evidence. SETTINGS: The review was not limited by time of publication or setting in which the studies conducted. PARTICIPANTS: HIV-exposed infants were participants. RESULTS: Database search and review of reference lists yielded 923 unique titles, out of which 16 studies involving 13,822 HIV exposed infants (HEI) were eligible for inclusion in the review. Included studies were published between 2014 and 2019 from Kenya, Nigeria, Uganda, South Africa, Zambia, and India. Of the 16 included studies, nine (experimental) and seven (observational) studies included had low to moderate risk of bias. The studies evaluated eHealth services (n = 6), service improvement (n = 4), service integration (n = 2), behavioral interventions (n = 3), and male partner involvement (n = 1). Overall, there was no evidence that any of the evaluated interventions, including eHealth, health systems improvements, integration of EID, conditional cash transfer, mother-to-mother support, or partner (male) involvement, was effective in increasing uptake of EID at 4-8 weeks of age. There was also no evidence that any intervention was effective in increasing HIV-infected infants' identification at 4-8 weeks of age. CONCLUSIONS: There is limited evidence to support the hypothesis that interventions implemented to increase uptake of EID were effective at 4-8 weeks of life. Further research is required to identify effective interventions that increase early infant diagnosis of HIV at 4-8 weeks of age. PROSPERO NUMBER: (CRD42020191738).

Levels and correlates of physical activity and capacity among HIV-infected compared to HIV-uninfected individuals.

INTRODUCTION: In the HIV-infected individuals, physical activity improves physical strength, quality of life and reduces the risk of developing non-communicable diseases. In Sub-Saharan Africa, HIV-infected patients report being less active compared to HIV-uninfected individuals. We assessed the levels and correlates of objectively measured physical activity and capacity among HIV-infected antiretroviral therapy (ART)-naive individuals compared to HIV-uninfected individuals in Mwanza, Tanzania. METHOD: We conducted a cross-sectional study among newly diagnosed HIV-infected ART-naive individuals and HIV-uninfected individuals frequency-matched for age and sex. Socio-demographic data, anthropometrics, CD4 counts, haemoglobin level, and C-reactive protein (CRP) were collected. Physical activity energy expenditure (PAEE) was assessed as measure of physical activity whereas sleeping heart rate (SHR) and grip strength were assessed as measures of physical capacity. Multivariable linear regression was used to assess the correlates associated with physical activity and capacity. RESULTS: A total of 272 HIV-infected and 119 HIV-uninfected individuals, mean age 39 years and 60% women participated in the study. Compared to HIV-uninfected individuals, HIV-infected had poorer physical activity and capacity: lower PAEE (-7.3 kj/kg/day, 95% CI: -11.2, -3.3), elevated SHR (7.7 beats/min, 95%CI: 10.1, 5.3) and reduced grip strength (-4.7 kg, 95%CI: -6.8, -2.8). In HIV-infected individuals, low body mass index, moderate-severe anaemia, low CD4 counts and high CRP were associated with lower physical activity and capacity. In HIV-uninfected individuals, abdominal obesity and moderate anaemia were associated with lower physical activity and capacity. CONCLUSION: HIV-infected participants had lower levels of physical activity and capacity than HIV-uninfected participants. Correlates of physical activity and capacity differed by HIV status. Management of HIV and related conditions needs to be provided effectively in health care facilities. Interventions promoting physical activity in these populations will be of importance to improve their health and reduce the risk of non-communicable diseases.

Diagnosis of human immunodeficiency virus associated disseminated intravascular coagulation.

INTRODUCTION: Disseminated intravascular Coagulation (DIC) is a thrombotic microangiopathy which may complicate a number of severe disease processes including sepsis. Development of microvascular thromboses results in consumption of coagulation factors and platelets and ultimate bleeding. Patients with HIV infection (PWH) often present with baseline dysregulation of the coagulation system which may increase severity and derangement of DIC presentation. Previously, we have shown that HIV is a significant risk factor for development of DIC. METHODOLOGY: We conducted a retrospective record review of all DIC screens submitted to our tertiary coagulation laboratory in Johannesburg, South Africa, over a one year period and compared the laboratory presentation of DIC in PWH with presentation of DIC in patients without HIV infection. RESULTS: Over the year, 246 patients fulfilled the International Society of Thrombosis and Haemostasis (ISTH) diagnostic criteria for DIC- 108 were confirmed HIV-infected and 77 were confirmed uninfected. PWH and DIC presented at a significantly earlier age (41 vs 46 years respectively, p<0.02). The prothrombin time was significantly more prolonged (30.1s vs 26.s), the d-dimer levels were substantially higher (5.89mg/L vs 4.52mg/L) and the fibrinogen (3.92g/L vs 1.73g/L) and platelet levels (64.8 vs 114.8x109/l) were significantly lower in PWH. PWH also showed significant synthetic liver dysfunction and higher background inflammation. CONCLUSION: PWH who fulfil the diagnostic criteria for DIC show significantly more dysregulation of the haemostatic system. This may reflect baseline abnormalities including endothelial dysfunction in the context of inflammation and liver dysfunction.

An analysis of the HIV testing cascade of a group of HIV-exposed infants from birth to 18 months in peri-urban Khayelitsha, South Africa.

BACKGROUND: Despite the reduction of HIV mother-to-child transmission, there are concerns regarding transmission rate in the breastfeeding period. We describe the routine uptake of 6 or 10 (6/10) weeks, 9 months and 18 months testing, with and without tracing, in a cohort of infants who received HIV PCR testing at birth (birth PCR) (with and without point of care (POC) testing) in a peri-urban primary health care setting in Khayelitsha, South Africa. METHODS: In this cohort study conducted between November 2014 and February 2018, HIV-positive mothers and their HIV-exposed babies were recruited at birth and all babies were tested with birth PCR. Results of routine 6/10 weeks PCR, 9 months and 18 months testing were followed up by a patient tracer. We compared testing at 6/10 weeks with a subgroup from historical cohort who was not tested with birth PCR. RESULTS: We found that the uptake of 6/10 weeks testing was 77%, compared to 82% with tracing. When including all infants in the cascade and comparing to a historical cohort without birth testing, we found that infants who tested a birth were 22% more likely to have a 6/10 weeks test compared to those not tested at birth. There was no significant difference between the uptake of 6/10 weeks testing after birth PCR POC versus birth PCR testing without POC. Uptake of 9 months and 18 months testing was 39% and 24% respectively. With intense tracing efforts, uptake increased to 45% and 34% respectively. CONCLUSION: Uptake of HIV testing for HIV-exposed uninfected infants in the first 18 months of life shows good completion of the 6/10 weeks PCR but suboptimal uptake of HIV testing at 9 months and 18 months, despite tracing efforts. Birth PCR testing did not negatively affect uptake of the 6/10 weeks HIV test compared to no birth PCR testing.

Prevalence and predictors of glucose metabolism disorders among People Living with HIV on combination antiretroviral therapy.

OBJECTIVE: We investigated prevalence and predictors of glucose metabolism disorders (GMDs) among People Living with HIV (PLWH) on efavirenz- and atazanavir/ritonavir-based combination antiretroviral therapy (cART). METHODS: This cross-sectional study involved adult PLWH on efavirenz- (n = 240) and atazanavir/ritonavir-based (n = 111) cART. The prevalence of GMDs was determined by fasting serum glucose, insulin, and homeostasis model assessment. A logistic regression model was used to determine predictors. RESULTS: The overall prevalence of GMDs for all regimens was 27.6% (97/351) [95% CI 23.0-32.6%] s, with 31.1% (75/240) [95% CI 25.4-37.5%] for efavirenz-based and 19.8% (22/111) [95% CI 12.9-28.5%)] for atazanavir/ritonavir-based cART group. The prevalence of impaired fasting glycemia was significantly higher (p = 0.026) in the efavirenz- [(15.4%) (37/240); 95%CI (11.1-20.6%)] than atazanavir/ritonavir-based [(7.2%) (8/111), (95%CI (3.2-13.7%)] cART. However, no significant difference was observed in the prevalence of diabetes mellitus and insulin resistance between the two regimens. Age ≥46 years old and specific type of ARV contained in cART, such as TDF, were independent predictors of GMD in both groups. Whereas the male gender and BMI category were predictors of GMDs among EFV-based cART group, AZT- and ABC- containing regimens and triglyceride levels were predictors in the ATV/r-based group. CONCLUSIONS: GMDs were highly prevalent among adults on EFV- than ATV/r-based cARTs. Age ≥46 years and TDF-containing cARTs are common predictors in both regimens. Close monitoring for impaired fasting glucose during long-term EFV-based cART is recommended for early diagnosis of type-2 diabetes and management.

Understanding the epidemiological HIV risk factors and underlying risk context for youth residing in or originating from the Middle East and North Africa (MENA) region: A scoping review of the literature.

INTRODUCTION: HIV is the second leading cause of death among young people globally, and adolescents are the only group where HIV mortality is not declining. Middle East and North Africa (MENA) is one of few regions seeing rapid increase of HIV infections (31.0%) since 2001. MENA youth are at particular risk of HIV due to dearth of research and challenges in accessing services. OBJECTIVE: The purpose of this scoping review is to establish the epidemiological HIV risk factors and underlying risk context for youth residing in or originating from the MENA region. METHODS: Online database searches were conducted using combination of search terms. Screening 5,853 citations, published between 1990-2019 with age groups 16 to 29, resulted in 57 studies included across 18 MENA countries. RESULTS: 'Key populations' engage in risky behaviors, including: overlapping risky behaviors among youth who inject drugs (PWID); lack of access to HIV testing, condomless sex, and multiple sex partners among young men who have sex with men (MSM); and high and overlapping risk behaviors among young sex workers. Challenges facing other youth groups and bridging populations include: peer pressure, inhibition about discussing sexual health, lack of credible sex education sources, low condom use, and lack of access to HIV protection/prevention services, especially testing. CONCLUSION: Poor surveillance coupled with scarcity of rigorous studies limit what is known about epidemiology of HIV among youth in MENA. Homophobia, stigma around PWID, and illegal status of sex work promote non-disclosure of risk behaviors among youth and curtail serving this population.

Pharmaceutical care and evaluation of adherence to antiretroviral therapy in people living with HIV/AIDS

Abstract Highly Active Antiretroviral therapy (HAART) depends on optimal adherence to be effective. Pharmacotherapeutic follow-up can be used as a strategy for treatment fidelity. To provide pharmaceutical care for HAART patients, to assess adherence, to identify and resolve drug related problems (DRP). This is a prospective, interventional study aimed at people on HAART. Data was collected using the pharmacotherapeutic follow-up form and CEAT-VIH. There was a predominance of women (59%), older than 33 years (75%), mostly single (43%). Regarding adherence, 64% had insufficient adherence at the start of the study, while 36% had strict/adequate adherence. After the pharmacotherapeutic follow-up, 70% presented strict/adequate adherence. Regarding HAART, the relationship between adhesion versus time of HAART and adherence versus regimen used was significant, considering that less time of therapy and regimen containing protease inhibitors are predictors for insufficient adherence. Regarding the DRP identified (f=77), missed pills (32%), untreated disease, incorrect management frequency, and undue self-medication (12%) were the most frequent. Pharmaceutical interventions (f=137) were predominantly advising related to specific pharmacological treatment (32%), non-pharmacological measures (20%), and medication suspension (9%). Pharmaceutical care was shown to be animportant strategy, within the multi professional team, to improve adherence, besides identifying and resolving DRP.

Indicación de profilaxis post exposición al VIH (PPE) en caso de relaciones sexuales sin preservativo o violencia sexual

Folleto elaborado en base a "Profilaxis Post Exposición para el VIH en personas adultas", del Ministerio de Salud de la Nación, Argentina.Se presenta un diagrama con posibles opciones de profilaxis.

Efavirenz dissolution enhancement V - A combined top down/bottom up approach on nanocrystals formulation

Abstract Efavirenz is one of the most commonly used drugs in HIV therapy. However the low water solubility tends to result in low bioavailability. Drug nanocrystals, should enhance the dissolution and consequently bioavailability. The aim of the present study was to obtain EFV nanocrystals prepared by an antisolvent technique and to further observe possible effect, on the resulting material, due to altering crystallization parameters. A solution containing EFV and a suitable solvent was added to an aqueous solution of particle stabilizers, under high shear agitation. Experimental conditions such as solvent/antisolvent ratio; drug load; solvent supersaturation; change of stabilizer; addition of milling step and solvents of different polarities were evaluated. Suspensions were characterized by particle size and zeta potential. After freeze- dried and the resulting powder was characterized by PXRD, infrared spectroscopy and SEM. Also dissolution profiles were obtained. Many alterations were not effective for enhancing EFV dissolution; some changes did not even produced nanosuspensions while other generated a different solid phase from the polymorph of raw material. Nevertheless reducing EFV load produced enhancement on dissolution profile. The most important modification was adding a milling step after precipitation. The resulting suspension was more uniform and the powder presented grater enhancement of dissolution efficacy.

Drugs of Abuse and Their Impact on Viral Pathogenesis.

Commonly misused substances such as alcohol, cocaine, heroin, methamphetamine, and opioids suppress immune responses and may impact viral pathogenesis. In recent years, illicit use of opioids has fueled outbreaks of several viral pathogens, including the human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV). This review focuses on the myriad of mechanisms by which drugs of abuse impact viral replication and disease progression. Virus-drug interactions can accelerate viral disease progression and lead to increased risk of virus transmission.

HOPX Plays a Critical Role in Antiretroviral Drugs Induced Epigenetic Modification and Cardiac Hypertrophy.

People living with HIV (PLWH) have to take an antiretroviral therapy (ART) for life and show noncommunicable illnesses such as chronic inflammation, immune activation, and multiorgan dysregulation. Recent studies suggest that long-term use of ART induces comorbid conditions and is one of the leading causes of heart failure in PLWH. However, the molecular mechanism of antiretroviral drugs (ARVs) induced heart failure is unclear. To determine the mechanism of ARVs induced cardiac dysfunction, we performed global transcriptomic profiling of ARVs treated neonatal rat ventricular cardiomyocytes in culture. Differentially expressed genes were identified by RNA-sequencing. Our data show that ARVs treatment causes upregulation of several biological functions associated with cardiotoxicity, hypertrophy, and heart failure. Global gene expression data were validated in cardiac tissue isolated from HIV patients having a history of ART. Interestingly, we found that homeodomain-only protein homeobox (HOPX) expression was significantly increased in cardiomyocytes treated with ARVs and in the heart tissue of HIV patients. Furthermore, we found that HOPX plays a crucial role in ARVs mediated cellular hypertrophy. Mechanistically, we found that HOPX plays a critical role in epigenetic regulation, through deacetylation of histone, while the HDAC inhibitor, Trichostatin A, can restore the acetylation level of histone 3 in the presence of ARVs.

New Insights in the Fight against HIV.

Effective antiviral immune responses rely on the host's genetic background and its interaction with the surrounding environment [...].

Evolution of Serum Acute-Phase Glycoproteins Assessed by 1H-NMR in HIV Elite Controllers.

Elite controllers (ECs) are an exceptional group of people living with HIV (PLWH) who maintain undetectable viral loads (VLs) despite not being on antiretroviral therapy (ART). However, this phenotype is heterogeneous, with some of these subjects losing virological control over time. In this longitudinal retrospective study, serum acute-phase glycoprotein profile assessed by proton nuclear magnetic resonance (1H-NMR) was determined in 11 transient controllers (TCs) who spontaneously lost virological control and 11 persistent controllers (PCs) who persistently maintained virological control over time. Both PCs and TCs showed similar acute-phase glycoprotein profiles, even when TCs lost the virological control (GlycB, p = 0.824 and GlycA, p = 0.710), and the serum acute-phase glycoprotein signature in PCs did not differ from that in HIV-negative subjects (GlycB, p = 0.151 and GlycA, p = 0.243). Differences in serum glycoproteins A and B were significant only in ECs compared to HIV-typical progressors (TPs) with < 100 CD4+ T-cells (p < 0.001). 1H-NMR acute-phase glycoprotein profile does not distinguish TCs form PCs before the loss of viral control. ECs maintain a low-grade inflammatory state compared to TPs. PCs revealed a closer serum signature to HIV-negative subjects, reaffirming this phenotype as a closer model of functional control of HIV.

Synthesis and Anti-HIV Activity of a Novel Series of Isoquinoline-Based CXCR4 Antagonists.

An expansion of the structure-activity relationship study of CXCR4 antagonists led to the synthesis of a series of isoquinolines, bearing a tetrahydroquinoline or a 3-methylpyridinyl moiety as head group. All compounds were investigated for CXCR4 affinity and antagonism in competition binding and calcium mobilization assays, respectively. In addition, the anti-HIV activity of all analogues was determined. All compounds showed excellent activity, with compound 24c being the most promising one, since it displayed consistently low nanomolar activity in the various assays.

Contribution to HIV Prevention and Treatment by Antibody-Mediated Effector Function and Advances in Broadly Neutralizing Antibody Delivery by Vectored Immunoprophylaxis.

HIV-1 broadly neutralizing antibodies (bNAbs) targeting the viral envelope have shown significant promise in both HIV prevention and viral clearance, including pivotal results against sensitive strains in the recent Antibody Mediated Prevention (AMP) trial. Studies of bNAb passive transfer in infected patients have demonstrated transient reduction of viral load at high concentrations that rebounds as bNAb is cleared from circulation. While neutralization is a crucial component of therapeutic efficacy, numerous studies have demonstrated that bNAbs can also mediate effector functions, such as antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP), and antibody-dependent complement deposition (ADCD). These functions have been shown to contribute towards protection in several models of HIV acquisition and in viral clearance during chronic infection, however the role of target epitope in facilitating these functions, as well as the contribution of individual innate functions in protection and viral clearance remain areas of active investigation. Despite their potential, the transient nature of antibody passive transfer limits the widespread use of bNAbs. To overcome this, we and others have demonstrated vectored antibody delivery capable of yielding long-lasting expression of bNAbs in vivo. Two clinical trials have shown that adeno-associated virus (AAV) delivery of bNAbs is safe and capable of sustained bNAb expression for over 18 months following a single intramuscular administration. Here, we review key concepts of effector functions mediated by bNAbs against HIV infection and the potential for vectored immunoprophylaxis as a means of producing bNAbs in patients.

The Interplay Among HIV, LINE-1, and the Interferon Signaling System.

Human immunodeficiency viruses (HIVs) are retroviruses that replicate effectively in human CD4+ cells and cause the development of acquired immune deficiency syndrome (AIDS). On the other hand, type 1 long interspersed elements (LINE-1s or L1s) are the only active retroelements that can replicate autonomously in human cells. They, along with other active yet nonautonomous retroelements, have been associated with autoimmune diseases. There are many similarities between HIV and LINE-1. Being derived (or evolved) from ancient retroviruses, both HIV and LINE-1 replicate through a process termed reverse transcription, activate endogenous DNA and RNA sensors, trigger innate immune activation to promote interferon (IFN) expression, and are suppressed by protein products of interferon-stimulated genes (ISGs). However, these similarities make it difficult to decipher or even speculate the relationship between HIV and LINE-1, especially regarding the involvement of the IFN signaling system. In this review, we summarize previous findings on the relationships between HIV and innate immune activation as well as between LINE-1 and IFN upregulation. We also attempt to elucidate the interplay among HIV, LINE-1, and the IFN signaling system in hopes of guiding future research directions for viral suppression and immune regulation.

Who falls between the cracks? Identifying eligible PrEP users among people with Sub-Saharan African migration background living in Antwerp, Belgium.

INTRODUCTION: This study produces an estimate of the proportion of eligible PrEP users among people of Sub-Saharan African background based on the Belgian PrEP eligibility criteria and examines associations with socio-economic and demographic characteristics. METHODS: We performed logistic regression analysis on data of a representative community-based survey conducted among Sub-Saharan African communities (n = 685) living in Antwerp. RESULTS: Almost a third (30.3%) of the respondents were eligible to use PrEP. Those who were male, single, lower educated, undocumented, and had experienced forced sex were more likely to be eligible for PrEP use. The findings highlight the importance of taking intra-, interpersonal and structural HIV risk factors into account. CONCLUSIONS: The study shows high unmet PrEP needs in this population, especially among those with high vulnerability for HIV acquisition. A better understanding of barriers to PrEP use in this population group is needed to allow for equitable access.

The Hitchhiker Guide to CD4+ T-Cell Depletion in Lentiviral Infection. A Critical Review of the Dynamics of the CD4+ T Cells in SIV and HIV Infection.

CD4+ T-cell depletion is pathognomonic for AIDS in both HIV and simian immunodeficiency virus (SIV) infections. It occurs early, is massive at mucosal sites, and is not entirely reverted by antiretroviral therapy (ART), particularly if initiated when T-cell functions are compromised. HIV/SIV infect and kill activated CCR5-expressing memory and effector CD4+ T-cells from the intestinal lamina propria. Acute CD4+ T-cell depletion is substantial in progressive, nonprogressive and controlled infections. Clinical outcome is predicted by the mucosal CD4+ T-cell recovery during chronic infection, with no recovery occurring in rapid progressors, and partial, transient recovery, the degree of which depends on the virus control, in normal and long-term progressors. The nonprogressive infection of African nonhuman primate SIV hosts is characterized by partial mucosal CD4+ T-cell restoration, despite high viral replication. Complete, albeit very slow, recovery of mucosal CD4+ T-cells occurs in controllers. Early ART does not prevent acute mucosal CD4+ T-cell depletion, yet it greatly improves their restoration, sometimes to preinfection levels. Comparative studies of the different models of SIV infection support a critical role of immune activation/inflammation (IA/INFL), in addition to viral replication, in CD4+ T-cell depletion, with immune restoration occurring only when these parameters are kept at bay. CD4+ T-cell depletion is persistent, and the recovery is very slow, even when both the virus and IA/INFL are completely controlled. Nevertheless, partial mucosal CD4+ T-cell recovery is sufficient for a healthy life in natural hosts. Cell death and loss of CD4+ T-cell subsets critical for gut health contribute to mucosal inflammation and enteropathy, which weaken the mucosal barrier, leading to microbial translocation, a major driver of IA/INFL. In turn, IA/INFL trigger CD4+ T-cells to become either viral targets or apoptotic, fueling their loss. CD4+ T-cell depletion also drives opportunistic infections, cancers, and comorbidities. It is thus critical to preserve CD4+ T cells (through early ART) during HIV/SIV infection. Even in early-treated subjects, residual IA/INFL can persist, preventing/delaying CD4+ T-cell restoration. New therapeutic strategies limiting mucosal pathology, microbial translocation and IA/INFL, to improve CD4+ T-cell recovery and the overall HIV prognosis are needed, and SIV models are extensively used to this goal.