Enhancement by Reducing Agents of the Transformation of Human and Rabbit Peripheral Lymphocytes

Abstract

Lymphocytes may be stimulated to undergo transformation into blast cells by a variety of nonspecific chemical agents, or by antiglobulin or antilymphocyte antisera. Antigens act as mitogenic agents on lymphocytes from sensitized animals (1-3). We have now observed that the action of various mitogens on human and rabbit peripheral lymphoeytes is markedly enhsnced in the presence of the reducing agents, l-cysteine, glutathione, or sulfite. Rabbit peripheral lymphocytes were isolated, purified on a cotton-wool column and cultured as described previously (4). Human leukocytes were obtained from the blood of normal individuals by allowing the cells to settle in 10% Plasmagel (Laboratoire Roger Bellon, Neuilly, France). The leukocyte-rich layer was removed and the cells were washed several times with 20% decomplemented fetal calf serum in Eagle's minimal essential medium (MEM). Leukocytes were cultured (4) at a concentration of 106 cells/ml. Rabbit lymphoeytes were cultured for 48 hr and human leukocytes for 108 hr; 24 hr before harvest, 5 µCi of 3H-thymidine (6.7 Ci/mM) was added to the rabbit lymphocyte cultures and either 5 µCi or 2 µCi of 3H-thymidine to the human leukocyte cultures. Radioactivity incorporated into DNA was determined as described previously (4).