Characterization of peripheral blood lymphocytes in sarcoidosis.

In the basal state, patients with sarcoidosis have reduced numbers of circulating T lymphocytes and a normal number of circulating B lymphocytes. The lymphocytes show impaired DNA synthesis in response to several mitogens and antigens and impaired K-cell cytotoxicity. Circulating atypical cells of lymphocytic origin are present belonging to both T- and B-cell lineages. After work (with mobilization of lymphocytes) the T-cell deficiency is further accentuated compared with normals. Moreover, after work a deficiency in the number of circulating B cells is also encountered. The atypical cells do not increase. Compared with normals the impaired K-cell cytotoxicity and lower levels of DNA synthesis also persist. It is suggested that the deviations found in sarcoidosis are consequences of a disease process affecting the lymphoid tissues and successively replacing the normal structures. The presence in vivo of DNA-synthesizing circulating lymphocytes may indicate a persistent antigenic stimulation.