Title of article :
The CD8β Ectodomain Contributes to the Augmented Coreceptor Function of CD8αβ Heterodimers Relative to CD8αα Homodimers
Author/Authors :
Witte، نويسنده , , Torsten and Spoerl، نويسنده , , Rebecca and Chang، نويسنده , , Hsiu-Ching، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 1999
Abstract :
Within the lymphoid compartment, CD8 is expressed either as an αα homodimer or as an αβ heterodimer. Prior functional characterization of CD8α transfectants has demonstrated that CD8αα homodimers can reconstitute T cell responses in the absence of the CD8β subunit. In order to now examine the role of CD8β in TCR recognition, the CD8α cDNA alone or in combination with CD8β cDNA was transfected into the mouse T cell hybridoma, N15wt, specific for VSV8/Kb. Comparison of antigen-induced IL-2 production reveals that CD8αβ+transfectants are 100-fold more sensitive in molar terms of peptide than CD8αα+transfectants. This enhancement of IL-2 production is independent of CD8α or CD8β cytoplasmic tails as demonstrated by analysis of cytoplasmic deletion mutants CD8α′β, CD8αβ′, and CD8α′β′. These results indicate that the ectodomain of the CD8β chain greatly enhances the coreceptor function of the CD8αβ molecule, at least for certain class I MHC restricted αβ TCRs.
Journal title :
Cellular Immunology
Journal title :
Cellular Immunology