Behavioural survey and street-based HIV and HCV rapid testing programme among transgender sex workers.

BACKGROUND: Transgender women sex workers (TGW-SW) are disproportionally affected by HIV and have reduced access to testing. Moreover, information regarding their behaviours and health needs is scarce. METHODS: A behavioural survey and a targeted testing programme in prostitution sites were conducted in Milan and Monza areas. The non-profit organisation 'ALA Milano Onlus' and 'San Gerardo' Hospital (Monza) implemented a mobile HIV testing unit involving a TGW peer educator, four physicians, a counsellor, a psychologist and a cultural mediator. All TGW-SW were offered anonymous HIV and hepatitis C virus (HCV) oral testing and asked to fill a questionnaire on sexual habits, drug abuse, and knowledge and attitudes towards HIV and STDs. RESULTS: Between May and July 2017, 130 TGW-SW, predominantly migrants, were contacted during 15 street visits; among them, 78 (60%) were interviewed. HIV and HCV testing were accepted by 53 (42%) and 67 (52%) TGW-SW, respectively. Twenty-five (19.8%) subjects who reported already established HIV infection were not retested. Seven patients received a new diagnosis of HIV, while nobody tested positive for HCV. Overall, HIV prevalence was 13.2% (25% including those with already known HIV infection). Recent arrival in Italy and young age were associated with risk of undiagnosed HIV infection. Inconsistent condom use was commonly reported during commercial sex (27%) and with non-commercial partners (64%). Alcohol and cocaine abuse were common problems which facilitated risky behaviours. CONCLUSIONS: Oral rapid HIV and HCV testing for TGW-SW in outreach settings were feasible and acceptable and led to a considerable number of new diagnoses. Interventions tailored to TGW-SW, focused on HIV prevention, testing and engagement in care, are fundamental.

HPV 16 and 18 contribute to development of anal dysplasia in HIV infection irrespective of gender and sexual orientation.

OBJECTIVES: The aim of the present study was too investigate prevalence and persistence of human papilloma virus (HPV) and cytological abnormalities (CAs) in the anal swabs of people living with HIV (PLWH): men who have sex with men (MSM), men who have sex with women (MSW) and women (W). METHODS: Between March 2010 and January 2019, an anal swab for cytological and HPV genotyping tests was offered to all PLWH attending our clinic. Logistic regression analysis was conducted to identify predictors of infection. RESULTS: In all, 354 PLWH were screened: 174 MSM, 90 MSW and 61 W. Prevalence of at least one high-risk (HR) HPV was higher in MSM (91%) and W (85%) than in MSW (77%) (P < 0.05). Cytological abnormalities were found in 21.1% of the entire population. At multivariable regression analysis a lower risk for HPV infection was found for W than for MSM [odds ratio = 0.24 (95% confidence interval: 0.115-0.513)] and for MSW than for MSM [0.37 (0.180-0.773)] and there was a significantly higher risk of CAs in PLWH with HPV 16 and 18 [3.3 (1.04-10.49)]. A total of 175 PLWH (103 MSM, 33 MSW and 26 W) had at least one follow-up visit (T1) after a median (interquartile range) follow-up of 3.6 (2.1-5.7) years. The acquisition rate of HR-HPV was high, with 66.7% of PLWH negative for HR-HPV at T0 who became positive at T1 (P < 0.001). The prevalence of CAs was stable (20.6%). A significant association between CAs at T1 and persistence of HPV-16 and/or 18 was found (P < 0.05). CONCLUSIONS: HPV 16 and 18 are associated with the presence and development of CAs irrespective of sexual orientation.

Evaluation of adhesion molecules and immune parameters in HIV-infected patients treated with an atazanavir/ritonavir- compared with a lopinavir/ritonavir-based regimen.

Objectives: To evaluate changes in pro-atherosclerotic biomarkers and endothelial function in patients initiating two different PI-based regimens as part of ART. Design: Prospective randomized 24 week study. Treatment-naive HIV-infected patients with CD4+ T cell count >250 cells/mm3 started PI-based regimens including atazanavir/ritonavir (Group A) or lopinavir/ritonavir (Group B) and were followed up in an observational follow-up study until week 96. Methods: The expression of immune activation and adhesion molecules on CD4+ and CD8+ cells and plasma cytokine levels were assessed at weeks 0, 4, 12, 24, 48, 72 and 96. Flow-mediated dilation (FMD), pulse-wave velocity (PWV) and intima-media thickness (IMT) were measured at weeks 0 and 24. Median changes within (signed rank test) and between (Wilcoxon test) arms were calculated. Results: Twenty-seven patients were enrolled, of whom 15 were treated with atazanavir/ritonavir and 12 with lopinavir/ritonavir. After 96 weeks of ART, CD25+/CD8+ T cells and plasma concentration of MCP-1/CCL-2 rose whereas CD44+/CD8+ T cells decreased significantly in both groups. Differences between treatments were noted for HLA-DRII+/CD8+, CD44+/CD4+ and CD11a+/CD4+, with significant increases in Group B versus Group A. No differences between groups regarding IMT, PWV and FMD were found at baseline and week 24. Conclusions: ART initiation with PI-based regimens led to a decrease in pro-atherosclerotic biomarkers at week 24, which then rebounded at week 96. Lopinavir/ritonavir treatment resulted in an unfavourable modulation of such markers compared with atazanavir/ritonavir treatment.

Changes in subcutaneous adipose tissue microRNA expression in HIV-infected patients.

OBJECTIVES: We evaluated the possibility that a pattern of abnormal microRNA (miRNA) expression could be fuelling the mechanisms causing HIV-associated lipodystrophy (HAL). METHODS: In this case-control study, samples of subcutaneous adipose tissue from eight consecutive HIV-infected patients on combination antiretroviral therapy with HAL (cases) were compared with those of eight HIV-negative subjects (controls). Human miRNA microarrays were used to probe the transcriptomes of the samples. Analysis of differentially expressed miRNAs was performed using DataAssist v2.0 software, applying a paired Student's t-test. RESULTS: Data showed that 21 miRNAs out of 754 were overexpressed in the patient group. Ten of these (i.e. miR-186, miR-199a-3p, miR-214, miR-374a, miR-487b, miR-532-5p, miR-628-5p, miR-874, miR-125-b-1* and miR-374b*) were up-regulated to a significant degree (fold change >2.5; P < 0.01). Eleven other miRNAs (i.e. miR-let-7d, miR-24, miR-30c, miR-125a-3p, miR-149, miR-191, miR-196-b, miR-218, miR-342-3p, miR-452 and miR-454*) were 2- to 2.5-fold more expressed in HIV+ samples than in controls. Levels of mRNA for lipin 1, the target of miR-218, were significantly lower in subcutaneous adipose tissue from HIV patients. CONCLUSIONS: In adipocytes of HIV-infected patients, the up-regulation of specific miRNAs could lead to an increased 'activation' that might contribute to the pathogenesis of HAL by increasing cell turnover and/or promotion of apoptosis.

Early prone positioning does not improve the outcome of patients with mild pneumonia due to SARS-CoV-2: results from an open-label randomised controlled trial - the EPCoT study.

Background: Prone positioning is routinely used among patients with COVID-19 requiring mechanical ventilation. However, its utility among spontaneously breathing patients is still debated. Methods: In an open-label randomised controlled trial, we enrolled patients hospitalised with mild COVID-19 pneumonia, whose arterial oxygen tension to inspiratory oxygen fraction ratio (PaO2/FIO2) was >200 mmHg and who did not require mechanical ventilation or continuous positive airway pressure at hospital admission. Patients were randomised 1:1 to prone positioning on top of standard of care (intervention group) versus standard of care only (controls). The primary composite outcome included death, mechanical ventilation, continuous positive airway pressure and PaO2/FIO2 <200 mmHg; secondary outcomes were oxygen weaning and hospital discharge. Results: A total of 61 subjects were enrolled, 29 adjudicated to prone positioning and 32 to the control group. By day 28, 24 out of 61 patients (39.3%) met the primary outcome: 16 because of a PaO2/FIO2 ratio <200 mmHg, five because of the need for continuous positive airway pressure and three because of the need for mechanical ventilation. Three patients died. Using an intention-to-treat approach, 15 out of 29 patients in the prone positioning group versus nine out of 32 controls met the primary outcome, corresponding to a significantly higher risk of progression among those randomised to prone positioning (HR 2.38, 95% CI 1.04-5.43; p=0.040). Using an as-treated approach, which included in the intervention group only patients who maintained prone positioning for ≥3 h·day-1, no significant differences were found between the two groups (HR 1.77, 95% CI 0.79-3.94; p=0.165). Also, we did not find any statistically significant difference in terms of time to oxygen weaning or hospital discharge between study arms in any of the analyses conducted. Conclusions: We observed no clinical benefit from prone positioning among spontaneously breathing patients with COVID-19 pneumonia requiring conventional oxygen therapy.

Unmasking tuberculosis in the era of antiretroviral treatment.

Tuberculosis (TB) can develop soon after antiretroviral treatment initiation, as the result of restoration of the anti-TB specific immune response. This form of the disease is often defined as "unmasked TB", and it represents a major challenge for severely immune-suppressed HIV-infected subjects initiating treatment. Emergence of previously unrecognised TB disease occurs frequently in countries where TB/HIV co-infection is common, and where antiretroviral treatment has become increasingly accessible. The challenges posed by unmasked TB, such as its high incidence, the lack of reliable diagnostic tools and the uncertainties on its optimal management, may hamper our ability to face the TB/HIV epidemic. Therefore, unmasked TB appears a major threat to global health and poses additional barriers to successful HIV/AIDS care and treatment programmes. This review focuses on the epidemiology, immunopathogenesis and clinical manifestations of unmasked TB, and provides evidence-based recommendations for management and care of the disease.

Ultrasonographic backscatter of the carotid artery wall in patients with HIV infection: a pilot study.

AIMS: The aim of our study was to measure carotid intima-media thickness (cIMT) and risk factors associated with its development and progression, and to evaluate arterial wall characteristics through integrated backscatter analysis (IBS) in HIV patients. METHODS: Perspective cohort study enrolling 44 HIV patients treated with antiretroviral drugs who underwent standard B Mode cIMT measurement and tissue characterization of carotid wall by means of dedicated software by acoustic densitometry, at time 0 and 2 years later. MAJOR FINDINGS: Cross-sectional evaluation performed at baseline found that cIMT value correlated significantly with age (r = 0.42, p = 0.005) and systolic blood pressure (r = 0.31, p = 0.04). No correlation was found between cIMT and CD4, HIV-RNA, triglycerides or total cholesterol. There was no difference between the group with versus the group with no protease inhibitors treatment. cIMT progression during 2 years of observation was statistically significant (median, interquartile range [IQR]: 0.005, 0-0.031). No correlation was found between IBS and duration of disease and kind of therapy, whereas a significant association was found between cIMT and IBS (r = 0.33, p = 0.03). No noticeable changes of IBS were observed during 2 years observation. CONCLUSIONS: Classic risk factors greatly affect cIMT than time of HIV infection, duration of antiretroviral therapy exposure and use of protease inhibitors. IBS is a promising technique for the evaluation of arterial wall composition in HIV patients.

HIV coinfection and antiretroviral therapy enhances liver steatosis in patients with hepatitis C, but only in those infected by HCV genotype other than 3.

BACKGROUND: Liver steatosis is a common finding in hepatitis C virus (HCV) infection and is associated with an increased progression of the disease. However, HCV genotype 3 steatosis presents a peculiar and virus-induced pathogenesis. We analysed the effect of HIV coinfection and antiretroviral therapy on hepatic steatosis and the effect of the steatosis on fibrosis in patients with or without HCV genotype 3 infection. METHODS: All consecutive HIV-infected and uninfected patients who had undergone a liver biopsy for evaluation of HCV infection at the Infectious Diseases Clinic (Modena, Italy) were included in this study. Primary outcomes were the presence or absence of steatosis or the presence of moderate or advanced fibrosis. RESULTS: A total of 284 patients were enrolled: 187 infected by HCV and 97 coinfected with HIV and HCV. In HCV genotype 3 patients, only HCV-related variables, such as plasma HCV RNA levels (odds ratio [OR] per log10 1.68, P < 0.001) and estimated duration of HCV infection (OR per year 1.17, P = 0.004) were associated with steatosis. In patients infected with other HCV genotypes, steatosis was associated with older age (OR per 5 years 1.47, P < 0.001), with exposure to d-drugs in HIV-HCV-coinfected patients (OR 2.60, P = 0.04) and specifically exposure to stavudine (OR 2.76 HIV-HCV-coinfected versus not HIV-infected patients, P = 0.04). Steatosis was independently associated with bridging fibrosis only in patients infected by HCV genotype other than 3 (OR 4.03, P = 0.01). CONCLUSIONS: Hepatic steatosis, in both HCV-monoinfected and in HIV-HCV-coinfected patients, is strongly correlated with HCV genotype 3, probably through interactions between HCV virus and liver cells. HIV-related increase of steatosis in patients with HCV is probably related to antiretroviral drugs, especially stavudine, in patients infected by HCV genotype other than 3.

Trough concentrations of lopinavir, nelfinavir, and nevirapine with standard dosing in human immunodeficiency virus-infected pregnant women receiving 3-drug combination regimens.

The objective of this study was to evaluate the plasma drug concentrations in human immunodeficiency virus (HIV)-infected pregnant women receiving highly active antiretroviral therapy (HAART) and to define the rate of occurrence of subtherapeutic concentrations for some commonly used antiretroviral drugs during pregnancy. We evaluated HIV-infected women (n = 68) in the third trimester of pregnancy in steady-state treatment with an HAART regimen administrated on a twice a day basis, which included 2 nucleoside reverse transcriptase inhibitors plus nelfinavir (NFV), lopinavir/ritonavir (LPV/r), or nevirapine (NVP). Blood samples were collected at predose (C(trough)). The following thresholds were used to define therapeutic drug concentrations-NFV: 0.8 microg/mL; LPV: 4.0 microg/mL/1.0 microg/mL (experienced/naive); and NVP: 3.1 microg/mL. At predose sampling, adequate drug concentrations were found in a higher proportion of women receiving NFV (70.8%) and LPV (75.0%) than NVP (55.6%). Median C(trough) plasma concentrations were 1.2 microg/mL for NFV, 5.5 microg/mL for LPV, and 3.1 microg/mL for NVP. Women receiving lopinavir/ritonavir had the lowest rates of detectable (>50 copies/mL) HIV RNA (15.4%) compared with rates of 22.2% and 41.7% among women receiving NVP and NFV, respectively. Genotypic resistance was detected in 50% of women with detectable HIV RNA for whom samples were available for testing. Subtherapeutic predose concentrations among HIV-infected pregnant women were more commonly found with NVP than with protease inhibitors. LPV administration was associated with the best viral load suppression.

Acute Human Immunodeficiency Virus (HIV) Infection Presenting With Bilateral Interstitial Pneumonia: Case Report and Discussion of Potential HIV-Induced Interstitial Pneumonia.

A 50-year-old man was admitted to intensive care unit because of acute respiratory failure due interstitial pneumonia; after admission, a diagnosis of acute human immunodeficiency virus (HIV)-1 infection was made. Clinical and radiological improvement was observed only after introduction of antiretroviral treatment. We discuss the hypothesis of interstitial pneumonia induced by the acute HIV-1 infection.

Risk of Chronic Kidney Disease among Patients Developing Mild Renal Impairment during Tenofovir-Containing Antiretroviral Treatment.

BACKGROUND: Tenofovir (TDF) can cause kidney injury through tubular dysfunction, with or without drop of estimated glomerular filtration rate (eGFR). Whether mild eGFR reductions during treatment should be considered a reason for prompt TDF discontinuation, however, remains unclear. METHODS: Patients with normal pre-TDF eGFR levels, who had developed mild renal impairment (i.e., two consecutive eGFR results between 89-60 ml/min) on TDF, were observed until onset of chronic kidney disease (CKD), defined as two eGFR<60 ml/min 3 to 6 months apart. Multivariable Poisson regression analysis was used to investigate whether outcome was associated with current and cumulative use of TDF (modeled as time-varying covariates). RESULTS: 2023 (29%) out of 6984 patients developed mild renal impairment on TDF. Among them, 191 progressed to CKD. The incidence of CKD did not significantly differ during TDF treatment (2.6 per 100 PYFU; 95%CI 2.2-3.2) or after its discontinuation (2.2 per 100 PYFU; 95%CI 1.8-2.6). However, the rate of CKD was significantly higher among patients continuing with TDF treatment compared to those who had discontinued it within 6 months of occurrence of mild renal impairment (aIRR 4, 95%CI 2.4-6.8). In contrast, among patients who had maintained TDF >6 months despite mild renal impairment, current TDF use was not associated with a significantly higher rate of CKD. Other significant predictors of CKD were older age, intravenous drug use, diabetes, hypertension, lower pre-TDF eGFR, higher eGFR drop since TDF introduction and longer exposure to TDF. CONCLUSIONS: Prompt discontinuation of TDF among patients developing mild renal impairment may prevent further progression of renal damage.

Evaluation of the Prognostic Value of Impaired Renal Function on Clinical Progression in a Large Cohort of HIV-Infected People Seen for Care in Italy.

Whilst renal dysfunction, especially mild impairment (6090, 60-89, <60 ml/min, was 2.91 (95% CI 2.30-3.67), 4.63 (95% CI 3.51-6.11) and 11.9 (95% CI 6.19-22.85) per 1,000 PYFU respectively, with an unadjusted hazard ratio (HR) of 4.14 (95%CI 2.07-8.29) for patients with eGFR <60 ml/min and 1.58 (95%CI 1.10-2.27) for eGFR 60-89 compared to those with eGFR ≥90. Of note, these estimates are adjusted for traditional cardio-vascular risk factors (e.g. smoking, diabetes, hypertension, dyslipidemia). Incidence of AIDS-related events was 9.51 (95%CI 8.35-10.83), 6.04 (95%CI 4.74-7.71) and 25.0 (95%CI 15.96-39.22) per 1,000 PYFU, among patients with eGFR >90, 60-89, <60 ml/min, respectively, with an unadjusted HR of 2.49 (95%CI 1.56-3.97) for patients with eGFR <60 ml/min and 0.68 (95%CI 0.52-0.90) for eGFR 60-89. The risk of AIDS events was significantly lower in mild renal dysfunction group even after adjustment for HIV-related characteristics. Our data confirm that impaired renal function is an important risk marker for CCVD events in the HIV-population; importantly, even those with mild renal impairment (90

Metabolic syndrome in human immunodeficiency virus-positive subjects: prevalence, phenotype, and related alterations in arterial structure and function.

BACKGROUND: Human immunodeficiency virus (HIV) infection itself and highly active antiretroviral treatment (HAART) have been proposed to be associated with a higher prevalence of metabolic syndrome, but, to date, prevalence and phenotype of metabolic syndrome among HIV subjects and the related structural and functional vascular alterations are not conclusively defined. METHODS: We analyzed the data of 108 HIV-infected subjects without known cardiovascular risk factors: 72 were on HAART (group A, age 46.5±7.5 years, clinical blood pressure 125.7/74.9±11.6/7.8 mmHg) and there 36 in a naïve group (group B, age 40.7±7.9 years, blood pressure 126/75.8±9.8/7.7 mmHg). A total of 224 healthy subjects served as controls (group C, age 44.9±6.9 years, blood pressure 123.7/75.7±9.8/7.1 mmHg). Arterial stiffness was measured by aorto-femoral pulse wave velocity (PWV, sfigmocor), and carotid intima media thickness (IMT) was measured by a semiautomatic echotracking system (Esaote-WTS). RESULTS: Metabolic syndrome was more frequent in HIV-positive subjects than in controls (19.4%, 13.8%, 4.5% for groups A, B, and C; P<0.001), with no significant difference between HAART and naïve. In metabolic syndrome subjects, group A displayed lipid profile alterations more frequently (91%, 50%, 57% for groups A, B, and C; P<0.05), whereas others metabolic syndrome components were equally represented in the three groups. In metabolic syndrome subjects, IMT was similar [556±108, 542±164, and 564±110.4 µm for groups A, B, and C; P=not significant (NS)], whereas PWV was significantly greater in HAART subjects when compared with controls (10.8±1.8, 9.±1.1, 9.3±1 cm/sec for groups A, B, and C; P=0.02 for A vs. C). Moreover, in this group (metabolic syndrome+HAART), PWV was higher than in subjects on HAART but without metabolic syndrome. CONCLUSIONS: HIV subjects showed a higher prevalence and a different pattern of metabolic syndrome components. HAART, more than HIV infection per se, appeared to be responsible for the increased prevalence of metabolic syndrome and arterial function derangement.

Decreased mitochondrial DNA content in subcutaneous fat from HIV-infected women taking antiretroviral therapy as measured at delivery.

BACKGROUND: Increasing numbers of pregnant HIV-positive women are receiving combination antiretroviral regimens for preventing mother-to-child virus transmission or for treating the infection itself. Several studies have demonstrated that nucleoside reverse transcriptase inhibitors (NRTIs) induce mitochondrial toxicity by several mechanisms, including depletion of mitochondrial DNA (mtDNA). By the quantification of mtDNA levels, we studied mitochondrial toxicity in HIV-positive women at delivery and the possible correlations with antiretroviral regimens, viroimmunological and metabolic parameters. METHODS: We analysed 68 HIV-positive women enrolled in the Italian Prospective Cohort Study on Efficacy and Toxicity of Antiretroviral in Pregnancy (TARGET Study); all were taking ≥1 NRTI. We quantified mtDNA copies per cell in subcutaneous fat samples collected during delivery. At the 3rd, 6th and 9th month of pregnancy, we collected data concerning CD4(+) T-cell count, plasma HIV RNA, total and high-density lipoprotein (HDL) cholesterol, fasting plasma glucose and triglycerides. As a control, we analysed mtDNA levels in abdominal subcutaneous fat samples from 23 HIV-seronegative women at delivery. RESULTS: mtDNA content was significantly lower in HIV-infected women when compared with HIV-negative controls. mtDNA content varied independently from viroimmunological, lipid and glucose parameters at the different months, with the exceptions of triglycerides at the 9th month and of HDL at the 6th month of pregnancy. CONCLUSIONS: In subcutaneous tissue from women taking NRTI-based antiretroviral regimens, we observed a significant decrease of mtDNA content, compared with uninfected women not on antiviral treatment. Moreover, a significant correlation was noted between mtDNA content and HDL cholesterol and triglycerides.

Qualitative immune modulation by interleukin-2 (IL-2) adjuvant therapy in immunological non responder HIV-infected patients.

BACKGROUND: Treatment of HIV-infected patients with interleukin-2 (IL-2) produces significant increases in CD4 T cell counts; however an associated qualitative improvement in cells function has yet to be conclusively demonstrated. By measuring mycobacterial killing activity, we evaluated IL-2-mediated functional immune enhancement ex vivo in immunological non-responders (INRs). METHODS AND FINDINGS: PBMC from 12 immunological non-responders (INRs) (CD4+<200/µl, HIV-RNA<50 cp/ml) on combination antiretroviral treatment (cART) were collected at baseline, and after 3 IL-2 cycles. Eight INRs receiving only cART were studied as controls. After 21 days of PBMC incubation with a virulent M. avium suspension, counts of residual colony forming units (CFUs) and concentrations of TNF-α, IL-10 and IFN-γ were determined. In IL-2 treated patients, a significant reduction in mean residual CFUs of PBMC cultures was observed (p<0.01). Moreover, following IL-2 treatment, significant increases in PBMC's IFNγ production (p = 0.02) and substantial reductions in IL-10 levels were observed. CONCLUSIONS: IL-2 therapy restores the ability of the lympho-monocyte system in eliciting an effective response against mycobacterial infections. Our data indicate the possibility of a clinical role held by IL-2 in enhancing the immune function of subjects unable to achieve immune competence through cART alone.

CD4+ T cell depletion, immune activation and increased production of regulatory T cells in the thymus of HIV-infected individuals.

Mechanisms by which HIV affects the thymus are multiple and only partially known, and the role of thymic dysfunction in HIV/AIDS immunopathogenesis remains poorly understood. To evaluate the effects of HIV infection on intra-thymic precursors of T cells in HIV-infected adults, we conducted a detailed immunophenotypic study of thymic tissue isolated from 7 HIV-infected and 10 HIV-negative adults who were to undergo heart surgery. We found that thymuses of HIV-infected individuals were characterized by a relative depletion of CD4+ single positive T cells and a corresponding enrichment of CD8+ single positive T cells. In addition, thymocytes derived from HIV-infected subjects showed increased levels of activated and proliferating cells. Our analysis also revealed a decreased expression of interleukin-7 receptor in early thymocytes from HIV-infected individuals, along with an increase in this same expression in mature double- and single-positive cells. Frequency of regulatory T cells (CD25+FoxP3+) was significantly increased in HIV-infected thymuses, particularly in priorly-committed CD4 single positive cells. Our data suggest that HIV infection is associated with a complex set of changes in the immunophenotype of thymocytes, including a reduction of intrathymic CD4+ T cell precursors, increased expression of activation markers, changes in the expression pattern of IL-7R and enrichment of T regulatory cells generation.