Induction of DNA synthesis in lymphocytes from ALG-treated patients.

Lymphocytes from kidney-grafted patients treated with anti-lymphocytic-globulin were found to be stimulated normally by phytohaemagglutinin to increased DNA synthesis, but to have lost their responsiveness to anti-lymphocyte serum. Lymphocytes from kidney-grafted patients, who were not treated with anti-lymphocytic globulin, and uraemic patients prior to transplantation, responded more or less normally to both phytohaemagglutinin and anti-lymphocyte serum. It is suggested that these findings cannot be explained by a shift in the cell populations as a consequence of anti-lymphocytic-globulin treatment, but rather by modulation of lymphocyte responsiveness to various triggering mechanisms.