ABNORMAL RESPONSE OF CULTURED LYMPHOCYTES TO PHYTOHEMAGGLUTININ AND AUTOLOGOUS SERUM IN CYSTIC-FIBROSIS

Abstract

Lymphocytes from [human] adults homozygous or heterozygous for cystic fibrosis show biochemical abnormalities when cultured for 48 h in the presence of phytohemagglutinin and autologous serum. In contrast to the 45% increase in total protein and .beta.-glucuronidase concentrations seen in healthy control subjects when measured per 1010 cells, both concentrations decreased by 1% in adults heterozygous for cystic fibrosis and 18% in adults homozygous for cystic fibrosis. The abnormal response of the lymphocytes from persons with cystic fibrosis was due to a serum factor and not to any intrinsic abnormality of the lymphocytes. An abnormal response to phytohemagglutinin occurred in only 14% of 44 healthy control subjects, but in 100% of 14 adults homozygous for cystic fibrosis and 85% of 26 adults presumed to be heterozygous for cystic fibrosis. As a result of this phenomenon, lymphocytic .beta.-glucuronidase concentrations were significantly lower than normal in patients with cystic fibrosis when the cells were cultured with phytohemagglutinin and autologous serum. The demonstration of this phenomenon in homozygotes and presumed heterozygotes (parents) suggests a relationship to the genetic defect in cystic fibrosis.