Binding of Concanavalin A to Rat, Normal Human, and Chronic Lymphatic Leukemia Lymphocytes

This study was aimed to find a correlation between the extent of concanavalin A (Con A) binding to lymphocytesand the blastogenic effect of the lectinon these cells. ⁶³Ni-labeled Con A wasused in the lectin-binding experiments.Binding of Con A to a small fraction(approximately 3%) of Con A bindingsites in rat lymphocytes is requiredfor the maximal stimulation of RNAsynthesis. Binding of Con A to additional sites resulted in a less stimulatory effect. Lymphocytes from patients with chronic lymphatic leukemia(CLL) are impaired in their blastogenicresponse to Con A. Maximal stimulation of DNA synthesis induced by ConA in CLL lymphocytes is attained bytreatment of the cells with the lectinat concentrations that are smaller thanthose required for the induction ofmaximal DNA synthesis in normallymphocytes. The number of Con Abinding sites in CLL lymphocyte issmaller than in normal lymphocyte.

Submitted on March 6, 1972 Revised on April 18, 1972 Accepted on April 27, 1972