Expression of C gamma 4 T cell receptors and lack of isotype exclusion by dendritic epidermal T cell lines
Koning, F.; Yokoyama, W.M.; Maloy, W.L.; Stingl, G.; Mcconnell, T.J.; Cohen, D.I.; Shevach, E.M.; Coligan, J.E.
Journal of Immunology 141(6): 2057-2062
1988
ISSN/ISBN: 0022-1767 PMID: 2971720 Document Number: 314932
Although four murine C.gamma. gene segments (C.gamma. 1, 2, 3, and 4) are known to exist, the large majority of expressed .gamma.-chains have been shown to be of the .eta.y1 isotype and no evidence exists for the expression of more than one receptor by .gamma.delta. TCR-bearing cells. We investigated the nature of the TCR expressed on a number of murine dendritic epidermal T cell-derived cell lines by using both Northern blot and immunoprecipitation analyses. One of these CD3+ cell lines (T195) expresses C.gamma.4, V.gamma.1, and .delta. mRNA, and its CD3-associated TCR complex can be precipitated by both anti-C.gamma.4 and anti-.delta. sera, indicating that this receptor is a C.gamma.4/.delta. heterodimer. Furthermore, we show that two cell lines (Y245, Y93) express two distinct TCR .gamma.-chains, one derived from the C.gamma.4 locus, whereas the second .gamma.-chain is probably derived from the C.gamma.2 locus. Together with the previous demonstration of C.gamma.1/.delta.TCR on a number of dendritic epidermal T cell lines (DETC), these results indicate that such DETC are capable of expressing a variety of y.delta. TCR and that, in some DETC, isotype exclusion of .gamma.-chain expression does not occur.