Astrocyte expression of major histocompatibility complex gene products in multiple sclerosis brain tissue obtained by stereotactic biopsy
R. M. Ransohoff and M. L. Estes
Department of Molecular Biology, Research Institute, Cleveland Clinic Foundation, OH 44195-5178.
Major histocompatibility complex (MHC) class I and class II antigens were
characterized by immunocytochemistry in two chronic-active multiple
sclerosis lesions in tissue obtained from two patients by stereotactic
biopsy. We examined in particular astrocytic MHC-positive cells in relation
to lesion architecture. The MHC class I (HLA-A,B,C)-positive astrocytic
cells were widely dispersed, being present at the lesion edge, in the
gliotic lesion center, and in normal-appearing white matter as well.
Morphologically astrocytic MHC class II (HLA-DR)-positive cells were
confined exclusively to the lesion edge. By staining serial sections with
antisera to glial-fibrillary acidic protein and HLA-DR, we confirmed the
lineage of several MHC class II-positive astrocytes. The demonstration of
MHC antigen-positive astrocytes in multiple sclerosis tissue obtained by
stereotactic biopsy is novel; the differential distribution of MHC class I-
and class II-positive astrocytes in the multiple sclerosis lesion may
provide suggestive clues about the regulation of MHC expression on these
cells in vivo.
