EVALUATION OF CD5 AND OTHER DIFFERENTIATION ANTIGENS ON HUMAN IMMUNOGLOBULIN-SECRETING CELLS USING A COMBINATION OF IMMUNOBEAD ROSETTING AND REVERSE HEMOLYTIC PLAQUE-FORMATION

This paper describes a new method, with high specificity and sensitivity, for evaluating cell surface markers such as differentiation antigens and cytokine receptors on immunoglobulin-secreting cells. Mononuclear cells, freshly derived from peripheral blood or following stimulation in vitro with pokeweed mitogen or Staphylococcus aureus Cowan I, are partially depleted of T cells and monocytes using immunomagnetic beads (Dynabeads) coated with anti-CD2. The cells are incubated with Dynabeads coated with monoclonal antibody against the cell marker under investigation and then used in a protein A haemolytic plaque assay. Plaque-forming cells (PFC) with (marker-positive) and without (marker-negative) attached beads can be readily enumerated. Values are given for percentages of IgG-, IgA- and IgM-PFC bearing CD19, CD38, CD25 and CD5. © 1990.