Direct cell mediated lympholysis by peripheral blood lymphocytes from renal allograft recipients.

Investigations of 22 kidney allograft recipients by the Direct CML-test revealed coincidence between acute allograft rejection and a positive test. 15 patients exhibited acute rejection, 3 chronic, and 4 no rejection episodes. 4 patients with acute rejection were not detected as positive in Direct CML, while 3 patients were positive without acute rejection, one having a chronic rejection. The exact role of HL-A antigens for the specificity of a positive Direct CML could not be evaluated from this material. It is concluded that the Direct CML-test may be helpful for the diagnosis of acute rejection, but that it has only limited power as the only test of recipients' response to foreign tissue.