Impaired response to alloantigens in HIV positive hemophilic patients.

The alloantigen responses of hemophilic patients was evaluated using a unidirectional mixed lymphocyte culture (MLC). The results of this study indicate that both the ability of peripheral blood mononuclear cells (PBMC) to proliferate in response to alloantigens and the capacity to stimulate the MLC are impaired in hemophilic patients infected with the human immune deficiency virus (HIV). These defects cannot be overcome by addition of exogenous interleukin-2 (IL-2) and are not related to the absence of IL-2 receptors (IL-2R). Lack of response was evident in PBMC from HIV+ patients with a high proportion of IL-2R+ cells. The number of IL-2 cells was similar in HIV+ and HIV- individuals, and higher than that of normal controls. Impaired MLC proliferation was not related to the occurrence of clinical symptoms. Apparently, MLC is a useful procedure for distinguishing the cell mediated immunity defects associated with HIV infection and unrelated to replacement therapy in hemophilia patients.