Action of Pronase on M and N Antigens on Human Erythrocytes

Pronase destroys M antigen on human red blood cells and simultaneously release M active sialogly copeptide from the cells, and, on the other hand, renders the treated cells agglutinable with anti-N serum. The activity of N red cells are slightly affected by the pronase treatment, but a passable amount of N act ive sialoglycopeptideis liberated from the cells. It is concluded from these results that N like substance which is hardly affected by pronase treatment is a basic substance in MN system on the red cells.