Heterogeneity of Lewis antibodies. A comparison of the reaction of human and animal reagents with synthetic oligosaccharides.

Human as well as animal anti-Lewis reagents were shown to have different binding patterns to synthetic structures chemically related to the Lewis epitopes. Two main types of cross-reactions were found: (1) Cross-reactions among type 1 Lewis epitopes (Lea, Leb and Lewis disaccharide). This type of cross-reaction among different type 1 structures was predominant in anti-Lea reagents (16 out of 18), although it was also present in some anti-Leb reagents (4 out of 14). (2) Cross-reactions of Lea and Leb with their type 2 isomers X and Y. The Leb-Y cross-reaction was more frequent (7 out of 14) than the Lea-X cross-reaction (2 out of 18). The serological property of some anti-Lewis reagents reacting with cord cells ('Lex') is also shown to be heterogeneous although probably related to common features of the type 1 Lea and Leb epitopes and independent of the type 2 X and Y epitopes.