Human lymphocyte differentiation markers and their application to immune deficiency and lymphoproliferative diseases.

The study of human lymphoid cell differentiation markers has recently yielded many insights into the pathogenesis of certain diseases which primarily affect the immune system. The application of these markers has, however, generated a host of new questions. Both technical difficulties and uncertainties concerning the significance of particular markers limit their routine application at the present time. Indeed, many studies in the literature, both in the diseases reviewed above, and perhaps to a greater degree in other conditions ('autoimmune' diseases, sarcoidosis, hepatitis and various infections) require re-evaluation in the light of recently increased sophistication about cell surfaces. Because of these qualificatins, the application of multiple characterizations of lymphoid cells using independent methodologies is necessary before any firm conclusions can be drawn in a particular clinical or experimental situation.