Astrocytes as antigen presenting cells for primary and secondary T cell responses: effect of astrocyte infection by murine hepatitis virus.

CD4+ T cell lines specific for murine hepatitis virus (MHV) - JHM or myelin basic protein (MBP) proliferated when cultured together with MHC class I and II positive syngeneic rat astrocytes and either inactivated virus or MBP as antigen. The magnitude of the T cell proliferative response was comparable to that seen when thymocytes were used as a source of antigen presenting cells (APC). In contrast, MHC class I and II positive astrocytes were unable to significantly stimulate the proliferation of highly purified populations of naive CD4+ and CD8+ T cells in an allogeneic mixed lymphocyte reaction (MLR). Both T cell populations proliferated when mixed with allogeneic lymph node cells. Infection of the astrocytes with a variant of MHV-JHM (PI-AS22D) did not alter this cells incapacity to stimulate the naive CD4+ and CD8+ T cells to proliferate.