The Biochemical and Molecular Characterization of T Cell Receptor of Thy-1^+ Derdritic Epidermal Cells.

本研究的第一个目的是阐明Thy-1^+树突状表皮细胞(Thy-1^+DEC)在小鼠体内的T细胞受体(TCR)表达。我们可以通过富集Thy-1^+DEC来免疫沉淀TCR复合体。用抗CD3和抗伽马链抗体在Thy-1^+DEC富集区的表皮细胞中检测到TCR；第二个目的是研究Thy-1^+DEC的功能作用。我们从裸鼠体内建立了Thy-1^+DEC细胞系，并检测到其杀伤活性。这些细胞在信使核糖核酸水平和蛋白水平表达穿孔素。我们进一步研究这些细胞是否有穿孔素。我们用流式细胞仪对正常小鼠的Thy-1^+DEC进行了纯化，发现Thy-1^+DEC表达穿孔素。Thy-1^+DEC的配体尚不清楚，但Thy-1^+DEC是一种杀伤T细胞，可能有助于皮肤的第一次免疫防御。第三，我们研究了Thy-1^+DEC对老龄小鼠的影响。在老年小鼠中，它们的数量减少了。IL-2能恢复老龄小鼠Thy-1^+DEC的数量。这些细胞继续表达TCR；；伽马；增量。最后，没有证据表明，在除小鼠以外的任何物种中都存在Thy-1^+DEC的对应物。利用新近研制的单抗，我们发现大鼠表皮中存在Thy-1^+DEC等价物。

The first purpose of our study was to clarify the T cell receptor (TCR) expression of Thy-1^+ dendritic epidermal cells (Thy-1^+DEC) in mice. We could enrich Thy-1^+DEC in order to immunoprecipitate TCR complex. TCR_<gamma> delta was found in Thy-1^+DEC enriched epidermal cells using anti CD3 and anti gamma chain antibodies. The second purpose was to investigate the functional role of Thy-1^+DEC. We could detect killing activity of the Thy-1^+DEC cell lines which we established from nude mice. These cells express perforin in mRNA level and protein level. We further investigate whether these cells in situ have perforin. We enriched Thy-1^+DEC from normal mice by FACS and found that Thy-1^+DEC expressed perforin. The ligand of Thy-1^+DEC is yet unknown, but Thy-1^+DEC is a killer T cell and may subserve the first immunologic defense in the skin. Thirdly, we studied Thy-1^+DEC in aged mice. They were decreased in number in old mice. Il-2 administration recover the number of Thy-1^+DEC even in old mice. These cells continue to express TCR_<gamma> delta. Lastly, there has been no evidence that there exist Thy-1^+DEC counterpart in any other species than mice. Using recently developed monoclonal antibody, we found there exist Thy-1^+DEC equivalent in rat epidermis.