Blood group B glycosphingolipids in alpha-galactosidase deficiency (Fabry disease): influence of secretor status. 
Defect in degradation of blood group B-immunoactive glycosphingolipids in Fabry disease (deficiency of lysosomal alpha-galactosidase EC 3.2.1.22) has been studied using highly sensitive and specific TLC-immunostaining analysis of urinary sediments and tonsillar tissues of blood group B patients and healthy controls, secretors and nonsecretors.  The B glycolipid antigens with hexasaccharide chains were consistently found increased (25- to 100-fold) in the urinary sediments of three Fabry patients, blood group B or AB secretors.  Conversely, they were absent in the urinary sediment of one blood group B nonsecretor patient.  In normal secretors, B glycosphingolipids were present only in traces.  Moreover, significant increase in B glycolipid antigens (8-fold) was found in the tonsillar tissue of a Fabry patient blood group B secretor.  We conclude that the secretor status is responsible for increased concentration of blood group B glycosphingolipids in both urinary cells and tonsils in alpha-galactosidase deficiency.  The quantity of stored B-immunoactive glycosphingolipids, however, is much lower than that of the mainly accumulated glycosphingolipid Gb(3)Cer.  The results clearly indicate that active or silent Se gene, which controls synthesis of B-antigen precursors, is responsible for notable difference in B-glycosphingolipids expression in Fabry patients - secretors and nonsecretors.  Whether this novel aspect may be of prognostic significance, remains to be established.