Kx Antigen, The McLeod Phenotype, and Chronic Granulomatous Disease: Further Studies

Abstract

Leukocytes of 9 unrelated boys with X-linked chronic granulomatous disease lack Kx antigen. In 3 of these cases, the red cells also lack Kx and have the McLeod phenotype and abnormal morphology. X-linked chronic granulomatous disease (CGD) can thus be separated into 2 types. Type I cases have an antigenic deficiency that is restricted to the phagocytic leukocytes while in type II, the deficiency involves both leukocytes and red cells. Red cells of type II CGD patients have enhanced i antigen activity suggesting that they are under hemopoietic stress. Normal Kx synthesis is directed by an X-linked gene named X1k. Three rare variants, X2k, X3k and X4k order the different permutations of leukocyte and red cell Kx antigen production that were recognized.