Measurement of H-2 and non-H-2 antigens in the mouse with the footpad swelling test.

The footpad swelling (FPS) test for delayed-type hypersensitivity in the mouse was evaluated for its ability to measure histocompatibility (H) antigens present on intact spleen cells or solubilized from a methylcholanthrene-(MCA) induced fibrosarcoma. Mice were immunized to H-antigens (H-2 or non-H-2) with skin allografts and challenged 14 days later with test antigens. Spleen cell-bound and solubilized H-antigens elicited strong and specific FPS reactions in allograft-immunized but not in unimmunized mice. The test could distinguish H-2 from non-H-2 antigens as well as D from KI region specificities of the H-2 gene complex. These experiments suggest that the FPS test is a reliable in vivo method for measuring both cell-bound and solubilized H-antigens in the mouse.