Developmental expression of alloantigen systems in the chicken

The different allelic forms of nine non-Mhc alloantigen systems of the chic ken were examined for developmental expression on erythrocytes isolated fro m embryos and young chicks. Polyclonal alloantisera raised against the diff erent antigens were used to detect these antigens on the cell surface by he magglutination as well as by indirect immunofluorescence. The developmental stage of initial expression on erythrocytes for each of the genetic system s investigated (i.e., A, E, C, D, H, I, K, L and P) varied from day 4 to da y 14 of incubation. The different antigens of each system appeared simultan eously at a particular stage of development except for those of the I syste m, where the I8 allelic form appeared earlier than I2. (C) 1999 Elsevier Sc ience Ltd. All rights reserved.