Biostatistics Unit. Faculty of Medicine.

Background  The pathogenesis of fat redistribution syndromes (FRS) observed in the setting of highly active antiretroviral therapy (HAART) for the treatment of HIV-1-infection remains elusive. A dysregulation of the tumour necrosis factor alpha (TNF-α) system occurs in HIV-infected patients with FRS.Materials and methods  The study looked at both the in vivo and in vitro relationship between TNF-α and the degree of subcutaneous adipocyte apoptosis in 60 HIV-1-infected patients on HAART with FRS, another 60 HIV-1-infected patients on HAART without FRS and 60 uninfected control patients. Apoptosis was assessed by the terminal deoxynucleotidyl transferase dUTP (deoxyuridine 5′-triphosphate)-digoxigenin Nick End Labelling (TUNEL) method. Soluble receptors of TNF-α were determined by the sandwich enzyme immunoassay technique. The in vitro viability was assessed by staining with 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) and apoptosis by TUNEL.Results  HIV-1-infected patients with FRS had significantly higher degrees of subcutaneous adipocyte apoptosis than those without FRS (P = 0·0001) and uninfected controls (P < 0·0001). There was a statistically significant association between serum levels of soluble TNF-α receptors #1 and #2 and the degree of subcutaneous adipocyte apoptosis in patients with and without FRS (P < 0·0001 for both receptors). In vitro, the addition of TNF-α (10 ng mL−1) to an adipocyte culture embedded with indinavir, either alone or in clinically relevant combinations with stavudine (d4T) and lamivudine (3TC), significantly decreased adipocyte viability (P = 0·0001) and increased adipocyte apoptosis (P < 0·0001) with respect to that observed with the addition of antiretrovirals alone.Conclusions  TNF-α plays a significant role in subcutaneous adipocyte apoptosis, which occurs in the setting of FRS in HIV-1-infected patients on highly active antiretroviral therapy.

A Phase I interventional Clinical Trial was performed with a potential tuberculosis vaccine, based on detoxified cellular fragments of M. tuberculosis, named RUTI®. The objective was to evaluate the safety profile and T-cell immune responses over a 6-month period following subcutaneous inoculation. The double-blind, randomized and placebo-controlled trial was conducted in healthy volunteers, all recruited at one site. RUTI®, at each of the four tested doses, starting from 5 μg and going up to 200 μg, and placebo were inoculated to groups of 4 and 2 volunteers respectively, consecutively. RUTI® appeared to be well tolerated as judged by local and systemic clinical evaluation, though vaccine dose dependent local adverse reactions were recorded. T-cell responses of blood lymphocytes to PPD and a number of antigen subunits were elevated, when compared with controls subjects. These results support the feasibility of future evaluation, to be targeted at subjects with latent tuberculosis infection (LTBI).