On the immunopathology of multiple sclerosis lesions

Active chronic multiple sclerosis (MS) lesions contain numerous T-200 and leukocyte function associated antigen (LFA)-1-positive infiltrating cells. Macrophages at the lesion edge are stained for immunoglobulins (Ig), Class I and Class II major histocompatibility complex (MHC) antigens, for interferon (IFN)-alpha and for the beta-2 integrin adhesion molecule gp 150/95. In the periplaque area, numerous CD2, CD4, and CD8 positive T cells and cells reactive for the CD45RO phenotype of memory cells and for gamma/delta T cell receptors are located between MHC-positive glial cells. White matter at the edge is diffusely stained for intercellular adhesion molecule (ICAM)-1 and LFA-3. Remote from lesions, labeling for Class II MHC, ICAM-1 and LFA-3 was enhanced on some endothelial and glial cells. These findings indicate that adhesion molecules are involved in the formation and possibly also in the reactivation of MS lesions.