Lymphocyte proliferative response to glial cells in SJL/J mice immunized with rat whole spinal cord and rat myelin basic protein.

Lymph node cells (LNC) from SJL/J mice immunized with either rat whole spinal cord (WSC) homogenate or rat myelin basic protein (MBP) in the presence of complete Freund's adjuvant were assayed for their in vitro proliferative response to MBP and whole or sonicated purified oligodendrocytes (OD), and astrocytes. WSC-immunized mice displayed a strong and persistent response to both syngeneic and rat OD, that disappeared after sonication (suggesting a preferential recognition of surface OD antigen(s], and a much weaker response to rat MBP. LNC from MBP-immunized mice showed a small response to MBP, but no response to OD, indicating that OD are not able to present their endogenous MBP to lymphocytes. Conversely, rat astrocytes (whole or sonicated), isolated from cultures initially comprising OD, could trigger the proliferative response of MBP-sensitized LNC, suggesting that astrocytes may act as antigen-presenting cells for OD products.