Assay for evaluation of cellular response to allergens

A method of evaluating hypersensitivity of leukocytes to antigens in the absence of a chromogenic indicator comprising the steps of:

• (a) introducing leukocyte-rich plasma in the absence of a chromogenic indicator into wells of multiwell plates wherein the bottoms of said wells of said plates provide an optically plane surface and wherein said wells have said antigens bound thereto;
• (b) incubating said plates for a sufficient period of time to activate the leukocytes in said wells which are sensitive to said antigens;
• and
• (c) examining said plates in a microtiter plate reader for evidence of activation, the evidence sought being a pale, blue-gray appearance of cytoplasmic and nuclear material of the leukocyte, a distinct and uniform halo that is colorless to pale blue around the leukocyte, and a uniform distribution of reactive leukocytes in the well, to identify wells having antigen bound thereto containing leukocytes which show evidence of activation.