Le Blood Group Research Articles

Identification of a novel heptaglycosylceramide with two fucose residues and a terminal hexosamine

A polar fucose-containing glycosphingolipid fraction isolated from dog small intestine has been characterized by mass spectrometry of intact methylated, and methylated and reduced (LiAlH 4) glycolipid. The native fraction, which was homogenous on thin-layer chromatography, was shown after methylation to be a mixture of two compounds. One was identified as a hexaglycosylceramide with the following composition and sequence: fucose-hexose-[fucose]-hexosamine-hexose-hexose-ceramide, with a terminal saccharide structure similar to blood group Le b determinants. The second compound was a novel heptaglycosylceramide with the sequence: hexosamine-[fucose]-hexose-[fucose]-hexosamine-hexose-hexose-ceramide. This glycolipid was also detected in human small intestine and pancreas. The dog intestinal fraction had phytosphingosine as its major base and contained almost exclusively 2-hydroxy fatty acids (16: 0–24: 0). The fraction of human pancreas differed in having sphingosine as its major base and normal fatty acids (16: 0–24: 0) as major acids.

Demonstration of Le x substance in the saliva of ABH non-secretors.

Abstract. Agglutination inhibition of anti‐Lex was observed with saliva from nonsecretor individuals of blood group Le(a–b–x–), even when these persons do not posses the Leb1 substance. This shows that the anti‐Lex must be different from anti‐Leb1 and that the receptor Lex is different from Leh1

Development of the isoserological system of Lewis during embryogenesis

The agglutinogen Le(a+) was demonstrated in the erythrocytes of 13 features spontaneously aborted on the 17–30th week of pregnancy, and of 12 newborn infants. The agglutinogen was present in these erythrocytes for all parental combinations of the Lewis system. The extent of secretion of the ABO agglutinogens was determined from the saliva of 47 parents and 6 newborn infants. Five of the infants were secretors and one was a nonsecretor. The presence in the erythrocytes of the newborn secretors of the Le(a+) agglutinogen was not in line with the relation characteristic of the adult system between the antigens of the Lewis and the ABO antigens. Thirty four parents with blood of the group Le(a−b+) were secretors, five which were Le(a+b−) were weak secretors or nonsecretors. Five persons of the blood group Le(a−b−) were secretors, and three were nonsecretors.