Chicken major histocompatibility complex class I definition using antisera induced by cloned class I sequences

Area of Science:

• Immunogenetics
• Avian immunology

Background:

• Chicken Major Histocompatibility Complex (MHC) or B-F/B-L (BFIV) antigens play a crucial role in immune responses.
• Defining specific BFIV alleles is essential for understanding chicken immune diversity and for breeding programs.

Purpose of the Study:

• To produce highly specific alloantisera against chicken class I BFIV antigens.
• To characterize cross-reactive epitopes and validate the utility of novel antisera for MHC haplotype definition.

Main Methods:

• Production of alloantisera using transfected cell lines expressing cloned BFIV sequences from specific haplotypes (*12, *13, *21).
• Development of laboratory-derived class I mutant sequences (BFIV13m126, BFIV21m78) to analyze cross-reactivity.
• Testing antisera specificity and reactivity using hemagglutination and flow cytometry assays on red blood cells from 31 MHC haplotypes.

Main Results:

• Generated alloantisera demonstrated high specificity with minimal cross-reactivity.
• Mutant BFIV21m78-induced antisera confirmed the importance of amino acids 78 and 81 in cross-reactivity between B*21 and B*5 haplotypes.
• Consistent hemagglutination patterns across 31 MHC haplotypes confirmed the utility of BFIV antisera for MHC definition.

Conclusions:

• The developed BFIV alloantisera are valuable reagents for precise MHC haplotype identification in chickens.
• Due to low recombination between chicken class I and II loci, BFIV allele identification aids in defining MHC haplotypes within chicken lines.
• Ensuring complete identity between transfected cell lines and chickens is critical for generating monospecific antisera.