abstract: the extreme polymorphism in mhc b-f genes enables the chickens to recognize enormous numbers of foreign peptides to trigger an immune reaction. study of this genetic resources is very important and it is essential to avoid the loss of genetic variability. genetic polymorphism among arian strain, a endogenous broiler chickens in iran, was investigated. in this study pcr-sscp was carrie...

background: indigenous chickens could serve as precious genetic resources that should be considered in conservation and breeding programs. the major histocompatibility complex (mhc) has a strong association to disease resistance/susceptibility, production and reproduction traits in chicken. therefore, identifying its polymorphism in populations under selective breeding could be used for selecti...

Major histocompatibility complex antigens are critical to an animal's immune response. In most animals, the extreme polymorphism of MHC molecules complicates studies of the role of this complex in the immune response. In mice, however, MHC haplotype-homozygous inbred strains have been developed which are invaluable in the study of the immune system and the search for immune response genes. The ...

Background: Major histocompatibility complex (MHC) is one of the best characterized genetic regions controlling immune responses against vaccines. Identifying the association between MHC haplotypes and improved immune responses would be useful in genetic breeding strategies in animals. OBJECTIVES: MHC class II B genetic diversity and its association with humoral immune responses against Newcast...

The major histocompatibility complex (MHC) is a key model of genetic polymorphism, but the mechanisms underlying its extreme variability are debated. Most hypotheses for MHC diversity focus on pathogen-driven selection and predict that MHC polymorphism evolves under the pressure of a diverse parasite fauna. Several studies reported that certain alleles offer protection against certain parasites...

Background: The role of Matrix Metalloproteinase 9 (MMP9) in tumor invasion and progression is prominent. A single nucleotide polymorphism (SNP) in the promoter region of MMP9 (-1562 C/T) increases the transcription and expression of this gene. On the other hand, MHC class I chain-related protein A and B (MICA/B) in soluble forms may impair tumor immunogenicity by reducing Natural Killer Group ...

HLA class I polymorphism creates diversity in epitope specificity and T cell repertoire. We show that HLA polymorphism also controls the choice of Ag presentation pathway. A single amino acid polymorphism that distinguishes HLA-B*4402 (Asp116) from B*4405 (Tyr116) permits B*4405 to constitutively acquire peptides without any detectable incorporation into the transporter associated with Ag prese...

A remarkable characteristic of the human major histocompatibility complex (MHC) is its extreme genetic diversity, which is maintained by balancing selection. In fact, the MHC complex remains one of the best-known examples of natural selection in humans, with well-established genetic signatures and biological mechanisms for the action of selection. Here, we present genetic and functional evidenc...

Distinguishing self from nonself and pathogenic from nonpathogenic is a fundamental challenge to the immune system but whether adaptive immune systems use pathogen-specific signatures to achieve this is largely unknown. By investigating the presentation of large sets of viruses and bacteria on MHC class I molecules, we analyze whether MHC-I molecules have a preference for pathogen-derived pepti...

The major histocompatibility complex (MHC) is a multigene complex of tightly linked homologous genes that encode cell surface antigens that play a key role in immune regulation and response to foreign antigens. In most species, MHC gene products display extreme antigenic polymorphism, and their variability has been interpreted to reflect an adaptive strategy for accommodating rapidly evolving i...