Characterization of WCl co-receptors on functionally distinct subpopulations of ruminant γδ T cells

WC I molecules are implicated in augmenting cellular activation as well as inducing cell cycle arrest of gamma delta T cells. Since WCI is a large multigene family differences in outcome could result from modulation of different WCI molecules. To further investigate this family of molecules, peripheral blood WC1(+) gamma delta T cell subpopulations were evaluated by 2-D Western blotting and RT-PCR. We found 13 cDNA intracytoplasmic tail sequences with differences in signaling motifs among them and at least 20 biochemically distinguishable WO spots associated with cell membranes, with some in lipid rafts. An understanding of the diversity of 2-D spots could not be resolved by evaluating T cell clones, removing sialyated carbohydrates or blotting with anti-WC1.1 or anti-WCI.2-specific antibodies. Nevertheless, while the major gamma delta T cell subpopulations in blood (WC1.1 +/WC1.2- and WC1.2+/WC1.2-) both had complex 2-D patterns, virtually all spots associated with WC1.2(+)/WC1.1(-) cells bore the WC1.2 epitope, distinguishing them from the WC1.1(+) cells. (c) 2006 Elsevier Inc. All rights reserved.