Title of article :
B-haplotype control of CD4/CD8 subsets and TCR Vβ usage in chicken T lymphocytes
Author/Authors :
Ewald، نويسنده , , Sandra J. and Lien، نويسنده , , Yi-Yang and Lanqing، نويسنده , , Li and Johnson، نويسنده , , L. Warren، نويسنده ,
Pages :
17
From page :
285
To page :
301
Abstract :
The major histocompatibility (B) complex of the chicken contains genes similar to Class I (B–F) and Class II (B–Lβ) genes in mammals, as well as a highly-polymorphic gene family (B–G) whose exact function is not known. Specific B-haplotypes are strongly associated with resistance to a number of infectious diseases, and with immune responses to soluble and cellular antigens. In mammals, Class I and Class II molecules control development of the T cell repertoire, including selection of CD4+ and CD8+ T cells. One study of chickens reported that low CD4:CD8 ratio was associated with the B4 haplotype, which shares expressed B–F / B–L genes with the B13 haplotype. In studies reported here, chickens of two haplotypes carried in the Auburn R line, B302 and B305 (which is B13-related), were evaluated for percentages of T cells expressing the CD4, CD8, CD3, TCR1, TCR2 and TCR3 antigens in peripheral blood lymphocytes (PBL), thymus, and spleen. These two haplotypes were chosen for comparison because they differ in resistance to Marekʹs disease (MD) and are closely-related in B–F and B–L genes by restriction fragment length polymorphism analyses. Homozygous birds of each B haplotype were produced from crosses of (B302 × B305)F1 sires and dams. PBL, thymocytes, and splenocytes from B302 homozygotes had higher CD4:CD8 ratios than B305 homozygotes. However, CD4:CD8 ratio differences could not be attributed to haplotype-controlled differences in Vβ usage within CD4/CD8 subsets, as has been described for certain Vβ families in mice and humans. These results indicate that thymic selection events involving CD4 and CD8 subsets and TCR Vβ usage are controlled by a gene or genes closely-linked to the B-complex, which may or may not be Class I or Class II genes.
Keywords :
Haplotype , chicken , lymphocyte
Journal title :
Astroparticle Physics
Record number :
2052894
Link To Document :
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