Failure of expression of alpha-3-L-fucosyltransferase in human serum is coincident with the absence of the X (or Le(x)) antigen in the kidney but not on leucocytes.
The X antigen, beta Gal(1----4)[alpha Fuc(1----3)]beta GlcNAc-R, is mostly found in epithelial cells of the digestive tract, proximal convoluted tubules of the kidney, and granulocytes. The alpha-3-L-fucosyltransferase responsible for synthesis of this antigen is normally present in the serum, but we found 2 individuals, a mother and her daughter, who lack more than 90% of the serum fucosyltransferase. They are of African origin and are both Le(a-b-). The young girl suffers from a congenital kidney anomaly: oligomeganephronic hypoplasia. Her kidney tubules are devoid of X antigen. However, her mother and herself normally possess the X antigen on granulocytes and its sialylated form on monocytes. Anephric patients showed reduced serum alpha-3-L-fucosyltransferase activity, suggesting that the kidney contributes to an important fraction of serum enzymic activity. It, therefore, appears that there are distinct genetic controls governing expression of the X antigen in different body compartments. Possibly, different alpha-3-L-fucosyltransferases could be at work in kidney and leucocytes.
Caillard
T
T
Institut d'Immunobiologie, ER-281 CNRS, Hôpital Broussais, Paris, France.
Le Pendu
J
J
Ventura
M
M
Mada
M
M
Rault
G
G
Mannoni
P
P
Oriol
R
R
D000017:ABO Blood-Group System / Q000276:immunology; D000911:Antibodies, Monoclonal; D002240:Carbohydrate Sequence; D002478:Cells, Cultured; D005260:Female; D005455:Fluorescent Antibody Technique; D005647:Fucosyltransferases / Q000097:blood / Q000172:deficiency*; D006017:Glycolipids / Q000096:biosynthesis / Q000172:deficiency*; D006602:Hexosyltransferases / Q000172:deficiency*; D006801:Humans; D007668:Kidney / Q000002:abnormalities*; D007684:Kidney Tubules / Q000276:immunology*; D007962:Leukocytes / Q000276:immunology*; D007983:Lewis Blood Group Antigens / Q000276:immunology; D016256:Lewis X Antigen; D008969:Molecular Sequence Data
D000017:ABO Blood-Group System; D000911:Antibodies, Monoclonal; D006017:Glycolipids; D007983:Lewis Blood Group Antigens; D016256:Lewis X Antigen; D005647:Fucosyltransferases; D006602:Hexosyltransferases; C031692:galactoside 3-fucosyltransferase