Immune-reactive cells in multiple sclerosis mucosal secretions.

External secretions from multiple sclerosis (MS) patients show immunoglobulin abnormalities consistent with mucosal inflammation. In this study we collected tears and parotid saliva from ten normal subjects and ten MS patients to examine for free-floating inflammatory cells. We found lymphocytes, macrophages, and plasma cells at low numbers in normal secretions, but at much higher numbers in MS secretions. Using an immunobead rosette technique, most of the lymphocytes were null cells. However, we found increased T lymphocytes in the secretions of clinically active MS patients. The extensive mucosal surfaces of the MS patient could provide a peripheral source for activated lymphocytes that subsequently enter brain.