Evaluation of antigen-induced buffy coat leucocyte aggregation as a simple test of allergic reactivity.

The phenomenon of antigen-induced aggregation of human buffy coat leucocytes correlates well with skin testing using purified protein derivative of tuberculin as the antigen and in this system appears to be a simple, sensitive test of cell-mediated immunity. The same phenomenon may, however, be used as an indicator of humoral immunity. In addition antigen-induced buffy coat leucocyte aggregation is suppressed by serum from patients with Hodgkin's disease and sarcoidosis. The possible uses and also the limitations of this test are discussed.