ObjectiveTo study the expression of HLA-G on peripheral blood mononuclear cells (PBMC) from HIV-1-infected individuals in order to determine whether this molecule is induced as a consequence of HIV-1 infection.DesignA total of 23 HIV-positive individuals in different stages of the disease were studied.MethodsFlow cytometric analysis and Western blot were used to measure HLA-G expression on PBMC obtained from HIV-positive and control individuals.ResultsMost of the monocytes obtained from HIV-1-infected individuals express HLA-G, whereas only a very low proportion of monocytes from healthy individuals express this molecule. When T lymphocytes from HIV-1 infections were studied, it was found that 30% of them express HLA-G, whereas only 1% were HLA-G-positive in healthy individuals. HLA-G expression was also confirmed by Western blot using specific anti-HLA-G monoclonal antibodies.ConclusionThe synthesis of HLA-G is increased in monocytes and certain T lymphocytes from HIV-1-infected individuals.