Effect of cyclosporin A (CyA) on the immunopathological lesion of the labial minor salivary glands from patients with Sjögren's syndrome.

Labial minor salivary gland biopsy specimens from 14 patients with Sjögren's syndrome treated either with cyclosporin A (CyA) or placebo (5 mg/kg body weight day for six months) were studied to determine T lymphocyte subsets and HLA-DR antigen expression using the avidin-biotin-peroxidase technique. In all CyA treated patients we observed a decrease in the number of T lymphocytes and in the number of T helper cells, while the percentage of T suppressor cells and B cells was the same in both treated and untreated groups. It was also shown that the HLA-DR antigen expression on the epithelial cells was eliminated in the CyA treated patients. These findings suggest that the HLA-DR antigen expression on the epithelial cells is the result rather than the triggering factor of this T cell mediated process and is probably related to decreased lymphokine production by activated T lymphocytes.