| Abstract: | Activation of microglial cells occurs during the pathogenesis of various neurologic diseases. However, the mechanisms of activation in vivo are still elusive. We infused adult rats intravenously with interferon-γ and demonstrated microglial cell activation after three days of treatment. We show for the first time that microglial cells proliferate inside the brain in response to a circulating cytokine. Microglial cells were induced to express major histocompatibility (MHC) class I and class II antigens and small amounts of leukocyte function-associated molecule 1 (LFA-1, CD11a). On endothelial cells of the brain, MHC class I and class II antigens and intercellular adhesion molecule 1 (ICAM-1, CD54) were enhanced. GLIA 19:181–189, 1997. © 1997 Wiley-Liss, Inc. |
