Demonstration of lymphocyte surface lectins that recognize sulphated polysaccharides.

Cholate extracts of murine lymphocytes were shown to contain haemagglutinating activity against autologous erythrocytes. The species specificity and sugar inhibition pattern of the haemagglutinin closely paralleled the specificity of autorosetting, an interaction that had been shown previously to involve the recognition by lymphocytes of carbohydrate structures on autologous erythrocytes. The probable identity of the haemagglutinin and autorosetting receptors was confirmed by experiments utilizing the unique plasma protein autorosette inhibition factor, which appears to block both interactions by masking carbohydrate acceptor sites on erythrocytes. Detailed sugar inhibition studies revealed that the haemagglutinin and autorosetting receptors have a high affinity for certain sulphated polysaccharides, such as heparin and dextran sulphate. Since similar sulphated polysaccharides have been shown previously to inhibit lymphocyte recirculation, a possible role for these receptors in lymphocyte homing and recirculation is discussed.