Article

Serological and molecular diversity in the cattle MHC class I region.

Institute for Animal Health, Compton, Newbury, UK.
Immunogenetics (impact factor: 2.93). 10/2005; 57(8):601-6. DOI:10.1007/s00251-005-0027-8
Source: PubMed

ABSTRACT Information on major histocompatibility complex (MHC) diversity in cattle is important to aid our understanding of immune responses and may contribute to maintenance of healthy cattle populations. Equally, understanding the mechanisms involved in generating this diversity may shed light on the complex nature of mammalian MHC evolution. The aim of this study was to assess molecular and serological variation within cattle MHC class I molecules and to study the mechanisms generating diversity. To address this aim, sequence variation was examined in 12 serologically assigned alleles from three putative loci and correlated with monoclonal antibody (mAb) binding data. The results demonstrate that both alloantisera and mAbs often fail to distinguish gene products that differ by a significant number of amino acids. Conversely, some mAbs could distinguish alleles differing by only one or two amino acids. Examination of the sequences demonstrates sharing of motifs between alleles, some encoded at distinct loci, supporting the occurrence of interlocus recombination within the cattle MHC class I region. The implications of this for MHC sequence diversity, and functional capability, are discussed.

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Keywords

12 serologically
 
alleles
 
alloantisera
 
amino acids
 
cattle MHC class
 
complex nature
 
distinct loci
 
distinguish gene products
 
encoded
 
functional capability
 
immune responses
 
interlocus recombination
 
mAb
 
mAbs
 
major histocompatibility complex
 
MHC sequence diversity
 
putative loci
 
sequence variation
 
sequences
 
serological variation