Chronic Granulomatous Disease, Kx Negative Neutrophils and Linkage with Xg

Abstract

Individuals afflicted with chronic granulomatous disease (CGD) suffer from recurrent infections due to the inability of their neutrophils to kill ingested microorganisms. Defective microbicidal function is a consequence of the inability of these cells to generate metabolites of oxygen which are toxic to ingested bacteria. This defect in oxidative activity is believed to be due to the absence or dysfunction of a membrane bound oxidase. In 1975, Marsh and co-workers (1) reported that neutrophils from patients with X-linked CGD, but not other forms of CGD, lacked a surface antigen called Kx. Kx is an X-linked, Kell-related antigen normally present on the surface of both red cells and granulocytic white cells. Its distribution on these two cell types is determined by any of four alleles that have been described at the Xk locus (2). Erythrocytic Kx is converted to the appropriate Kell antigen by an autosomally determined enzyme. Thus, Kx is believed to serve as a precursor substance for Kell antigens on red cells, whereas on granulocytes it remains unaltered.