The Diverse Major Histocompatibility Complex Haplotypes of a Common Commercial Chicken Line and Their Effect on Marek’s Disease Virus Pathogenesis and Tumorigenesis

Abstract

The major histocompatibility complex (MHC) is crucial for appropriate immune responses against invading pathogens. Chickens possess a single predominantly-expressed class I molecule with strong associations between disease resistance and MHC haplotype. For Marek’s disease virus (MDV) infections of chickens, the MHC haplotype is one of the major determinants of genetic resistance and susceptibility. VALO specific pathogen free (SPF) chickens are widely used in biomedical research and vaccine production. While valuable findings originate from MDV infections of VALO SPF chickens, their MHC haplotypes and associated disease resistance remained elusive. In this study, we used several typing systems to show that VALO SPF chickens possess MHC haplotypes that include B9, B9:02, B15, B19 and B21 at various frequencies. Moreover, we associate the MHC haplotypes to MDV-induced disease and lymphoma formation and found that B15 homozygotes had the lowest tumor incidence while B21 homozygotes had the lowest number of organs with tumors. Finally, we found transmission at variable levels to all contact birds except B15/B21 heterozygotes. These data have immediate implications for the use of VALO SPF chickens and eggs in the life sciences and add another piece to the puzzle of the chicken MHC complex and its role in infections with this oncogenic herpesvirus.

Fourth Report on Chicken Genes and Chromosomes 2022

“…A classic example is the presence of isochores that separate by Giemsa staining and by density centrifugation. In mammals, GCrich isochores are considered to replicate earlier in the cell cycle than AT-rich isochores, and also have a greater density of genes which are more compact [Constantini and Musto, 2017;Bernardi, 2021]. Analyses of the chicken B locus illustrate regions that differ in another way: the BF-BL region (which corresponds to the major histocompatibility complex, MHC) is relatively compact and stable with little obvious recombination, whereas the BG region undergoes frequent expansion and contraction leading to copy number variation (CNV).…”

“…Altogether, 22 different MiSeq runs were performed covering roughly 20,000 samples. For some populations, we used the microsatellite LEI0258 [Fulton et al, 2006] and BF2-specific PCRs Cytogenet Genome Res 2022;162:405-527 DOI: 10.1159/000529376 to confirm and extend the assignments [Bertzbach et al, 2022;L. Huynh, C.A.…”

Role of gga-miR-29b-3p in suppressing the proliferation, invasion and migration of MSB1 Marek’s disease tumor cells by the targeting of the DNMT3B gene

“…Marek's disease (MD) is infectious disease in poultry that is caused by a highly cell-bound herpesvirus [MD virus (MDV)], which was characterized by immunosuppression and polyneuritis (1,2). It has been found across a range of commercial poultry species, in chickens and quail initially and later in turkeys (3,4).…”