Induction and Expansion of T Cell Repertoire Using Growth Hormone and Vaccination in HIV-1 Infected Patients

• Proportion of patients HIV+ that recover the immunospecific responses against tetanus toxoid and Hepatitis A at 24 weeks of rhGH administration (time of treatment interruption). [ Time Frame: from 24 weeks post rhGH administration ] [ Designated as safety issue: Yes ]
  

• The rhGH activates the thymic function. [ Time Frame: from one year post rhGH administration ] [ Designated as safety issue: Yes ]
  
• This effect is lasting once the rhGH administration is interrupted. [ Time Frame: from at least one year since the last rhGH administration ] [ Designated as safety issue: Yes ]
  

The purpose of a therapeutic vaccine is to control, induce and expand humoral and cellular immune responses capable to control HIV infection. The administration of a conventional vaccine results in the expansion of peripheral clones. Concomitant administration of rhGH may boost this expansion and reconstitute specific T cell responses not achievable by vaccination alone. In this study we want to investigate whether the administration of rhGH expand T cell repertoire and whether there is an increase in the specific cellular responses to HIV-1 and recall antigens and, lately, whether this responses can be further amplified after immunization with tetanus toxoid and hepatitis A vaccines. This Hypothesis will be evaluated by the measurement of thymic volume, the expansion of naïve, memory and effector cell subsets, analysis of thymic emigrants (TRECs) before, during and after rhGH administration and vaccination. Moreover, T cell receptor rearrangement, specific antibodies and cellular responses to antigenic peptides will be determined.