Some properties of the human erythrocyte receptors for Neisseria gonorrhoeae.

The nature of the receptors for T1 and T4 Neisseria gonorrhoeae on erythrocytes and other cells was investigated. In general, cells of nonprimate origin contained few receptors for gonococci. Receptors for T4 gonococci were only uncovered when host cells were pretreated with trypsin. Trypsinization, while unnecessary for T1 adherence to erythrocytes, enhanced attachment in inverse proportion to original erythrocyte sensitivity. Receptors for T1 and T4 organisms on trypsinized and trypsin-neuraminidase-treated erythrocytes were blocked by concanavalin A and peanut lectins, respectively, but a distinction could be made between them with wheat germ lectin and galactose oxidase. Of a number of sugars tested as inhibitors, only D-galactose blocked adherence of T4 but was without effect on T1. While the identity of erythrocyte receptors is uncertain, likely candidates are "band 3" protein and glycophorin, by virtue of their galactose content, lectin binding capacity, and partial exposure on the outer surface of the erythrocyte.