The dominantly expressed class II molecule from a resistant MHC haplotype presents only a few Marek’s disease virus peptides by using an unprecedented binding motif

Viral diseases pose major threats to humans and other animals, including the billions of chickens that are an important food source as well a public health concern due zoonotic pathogens. Unlike typical mammals, histocompatibility complex (MHC) can confer decisive resistance or susceptibility many viral diseases. An iconic example is Marek’s disease, caused by oncogenic herpesvirus with over 100 genes. Classical MHC class I II molecules present antigenic peptides T lymphocytes, it has been hard understand how such could be involved in given potential number from We used new vitro infection system immunopeptidomics determine peptide motifs for 2 expressed haplotype B2, which known disease. Surprisingly, we found vast majority epitopes presented chicken arise only 4 genes, nearly all having motif BL2*02, dominantly molecule chickens. BL2*02 linked several disease virus (MDV) determined one X-ray crystal structure, showing single small amino acid binding site causes crinkle peptide, leading core 10 acids, compared 9 acids reported molecules. The limited cell explain differential MHC-determined MDV, but raises questions mechanism opportunities vaccine targets this species, providing basis understanding species humans.