Adaptation of the ⁵¹cr cytotoxic assay for rapid H-2 classifications on peripheral blood cells

A new method for rapid, routine classifications of H-2 type for genetic crosses or wild populations is described. It is based upon absorption in the standard ⁵¹cr cytotoxic assay, with small quantities of washed peripheral blood cells (erythrocytes and leukocytes), which may be obtained without killing the test animal. After initial absorption, the blood cells are sedimented and the remainder of the test is completed, without removal of the absorption supernatant, thus substantially enhancing the speed and efficiency of the test. Data are presented to demonstrate that the method is comparable, if not superior, to the standard hemagglutination technique.