Study halted prematurely due to the difficulties in dedicating the human resources necessary to conduct the study deriving from the COVID-19 pandemic, but potentially will resume

A longitudinal observational study in HIV-infected subjects receiving cART addressed to explore the effect of the Tat protein and anti-Tat immunity on the formation and maintenance of HIV-1 virus reservoir.

The study is designed as a longitudinal observational study addressed to identify the effects of Tat protein and humoral/cellular anti-Tat immune responses (induced in the natural infection or by Tat vaccination) in HIV-1 reservoir dynamics in blood of HIV infected patients receiving cART. HIV DNA data will be used for analyzing the decay dynamics.

The primary objective of the study is to determine the rate of decay of total HIV DNA in blood of anti-Tat antibody (Ab) positive versus anti-Tat Ab negative HIV patients receiving cART.

The secondary objectives of the study are to relate the HIV DNA decay data to:

1. the persistence of anti-Tat humoral responses;
2. biomarkers of HIV reservoir stability potentially affected by the Tat protein or anti-Tat immune responses, including: i) apoptotic/survival index of CD4+ T cells; ii) reactivation dynamics of latent HIV in resting CD4+ T cells upon exposure to Tat protein and/or activation stimuli; iii) cellular and humoral biomarkers relevant to inflammation and immune dysregulation.

Inclusion Criteria:

1. Age ≥18 years
2. Diagnosis of HIV-1 infection
3. To be under cART treatment
4. CD4+ T-cell count ≥250 cells/microliters
5. Testing for anti-Tat Ab performed during pre-screening
6. Signed informed consent

Exclusion Criteria:

1. Current therapy with immunomodulators or immunosuppressive drugs or chemotherapy for neoplastic disorders.

HIV-1 infected adult subjects of either gender, ≥18 years old, under cART, with CD4+ T-cell count ≥250 cells/µL.