Binding of cholera toxin to pig intestinal mucosa glycosphingolipids: relationship with the ABO blood group system.
A search for compounds from intestinal mucosa of pigs carrying and not carrying blood group A-active substances (A+ and A- pigs, respectively) capable of binding cholera toxin (CT) was performed. Glycolipid extracts from a pool of pig intestinal mucosa resolved in thin-layer chromatography (TLC) revealed the presence of six to eight compounds capable of binding 125I-CT, two of them running as the ganglioside standards GM1 and GD1b. When intestinal mucosa glycolipids from single pigs were assayed by TLC for CT-binding capacity, two different patterns of labeling were observed. The main difference was at the level of compounds running below GD1b. The A+ pigs but not the A- pigs showed CT binding at this level. The major CT-binding compound detected only in A+ pigs was purified and some properties were determined. After TLC developed with different solvent systems, the purified compound bound CT and also immunoreacted with anti-A and anti-AB antisera but not with anti-B antiserum. The compound was also able to inhibit the hemagglutination of human A erythrocytes caused by anti-A antiserum, but inhibition was not observed with the B-anti-B or O (H)-Ulex europaeus lectin systems. A partial chemical characterization indicated that the active compound is a neutral glycosphingolipid containing glucose, fucose, galactose, and hexosamine. The existence of a blood group-active substance(s) able to interact with CT may help to explain the relationship between ABO blood groups and the diarrheal disease caused by infection with Vibrio cholerae.
Bennun
F R
FR
Departamento de Quimica Biologica, Facultad de Ciencias Quimicas, Universidad Nacional de Cordoba, CIQUIBIC-CONICET, Argentina.
Roth
G A
GA
Monferran
C G
CG
Cumar
F A
FA
D000017:ABO Blood-Group System; D000818:Animals; D001665:Binding Sites; D002772:Cholera Toxin / Q000378:metabolism*; D002855:Chromatography, Thin Layer; D006028:Glycosphingolipids / Q000378:metabolism*; D066298:In Vitro Techniques; D007413:Intestinal Mucosa / Q000276:immunology / Q000382:microbiology*; D013552:Swine / Q000097:blood / Q000382:microbiology*
D000017:ABO Blood-Group System; D006028:Glycosphingolipids; D002772:Cholera Toxin