Multiple sclerosis: a quantitive and qualitative study of immunoglobu‐lin‐containing cells in the central nervous system

Autopsy material from the brains and spinal cords of twenty‐three patients with multiple sclerosis was examined with the immunoperoxidase (PAP) method to compare the distribution of immunoglobulin (Ig)‐containing cells in demyelinated plaques and normally myelinated tissue. Ig‐containing cells were much more numerous within plaques than outside them and were more common in recent than in old plaques. Most of the heavy chain present was IgG with small amounts also of IgA. More cells were demonstrated to contain light chains than heavy chains. It is suggested on the basis of the pattern of distribution of Ig‐containing cells that a stimulus to B‐cell proliferation and maturation resides within plaques.