In the 7 years since the last review of lymphocyte markers, written by Tomasi and Stobo, appeared in this journal, there has been a revolution in the diversity and sophistication of immunologic tests directly applicable to investigations of clinical disorders. The promise of such procedures and their allied genetic and monoclonal antibody probes in aiding the classification, early recognition, and therapy of hematologic malignancies, autoimmune disorders, and infectious diseases now is approaching fruition. A synopsis of those assays in vitro and in vivo, together with the primary immune cell subsets they define, is given in Table 12. A grasp of the basic mechanisms underlying them should permit their judicious use, as they are requested either through the clinical laboratory (the initial screen) or as they are complemented by more complex studies obtained through university-affiliated immunology centers (further workup). In this manner, clinically relevant information for the diagnosis and treatment of disorders of immune function will be realized.
