Kraig E, Kannapell C C, Fischbach K, Zellmer V, Trial J
Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio 78284.
J Immunol. 1990 Oct 1;145(7):2050-6.
Two splenic cell clones were derived from mice bearing UV-induced skin tumors; both clones are I-J+, Thy-1+, and J11D+. Cellular extracts, but not culture supernatants, from the two clones, designated T4 and T5, specifically suppress primary cytotoxic and proliferative responses to UV-induced tumor targets. Therefore, clones T4 and T5 would appear to function as putative I-J+ suppressor cells with specificity for an antigenic epitope common to several UV-induced tumors. To derive more information concerning the status of Ag-receptor genes in the suppressive clones, we analyzed the rearrangement and expression of Ig and TCR genes. The first clone, T4, expressed Thy-1, a T cell-surface marker, yet it had not rearranged its TCR-beta, -gamma, and -delta gene families, nor were TCR-alpha, -beta, -gamma, or -delta transcripts detectable. Instead, clone T4 contained rearranged Ig H chain genes and expressed mu RNA. Because neither lambda nor kappa L chain transcripts were detected, this clone could not utilize a complete Ig molecule as its Ag receptor. On the other hand, clone T5 contained exclusively TCR gene rearrangements; it expressed alpha and beta transcripts of the correct sizes. However, the level of RNA that could encode the delta-chain of the CD3 accessory molecule was below detection, so it is unlikely that this TCR was expressed on the cell surface. The rearrangement of Ig genes in one clone and TCR genes in the other clone does not necessarily indicate that these genes encode the Ag receptors used by these clones. However, it suggests either that suppressor-like cells can derive from different lymphocyte precursor lineages or that rearrangements of the known TCR genes or the Ig genes are irrelevant to the function of this cell lineage.
从患有紫外线诱导皮肤肿瘤的小鼠中获得了两个脾细胞克隆；这两个克隆均为I-J⁺、Thy-1⁺和J11D⁺。来自这两个分别命名为T4和T5的克隆的细胞提取物（而非培养上清液）可特异性抑制对紫外线诱导肿瘤靶标的原发性细胞毒性和增殖反应。因此，克隆T4和T5似乎作为假定的I-J⁺抑制细胞发挥作用，对几种紫外线诱导肿瘤共有的抗原表位具有特异性。为了获得更多关于抑制性克隆中抗原受体基因状态的信息，我们分析了Ig和TCR基因的重排和表达。第一个克隆T4表达T细胞表面标志物Thy-1，但它未重排其TCR-β、-γ和-δ基因家族，也未检测到TCR-α、-β、-γ或-δ转录本。相反，克隆T4含有重排的Ig重链基因并表达μRNA。由于未检测到λ或κ轻链转录本，该克隆无法利用完整的Ig分子作为其抗原受体。另一方面，克隆T5仅含有TCR基因重排；它表达了正确大小的α和β转录本。然而，可编码CD3辅助分子δ链的RNA水平低于检测限，因此该TCR不太可能在细胞表面表达。一个克隆中Ig基因的重排和另一个克隆中TCR基因的重排并不一定表明这些基因编码这些克隆所使用的抗原受体。然而，这表明要么抑制样细胞可源自不同的淋巴细胞前体谱系，要么已知TCR基因或Ig基因的重排与该细胞谱系的功能无关。
