T cell response against stress proteins

我们先前报道，随着大鼠成纤维细胞的肿瘤转化，细胞表面表达70 kDa热休克相关蛋白样分子(Hsc70)，该分子可被CD3^+、CD4^-、CD8^-、NKR-P1^-和TCR-_lt；α&gt；β^-T(DNT)杀伤细胞以MHC类I型不受限制的方式识别。我们研究了hsc70与DNT细胞相互作用的机制。H-ras癌基因转化的大鼠纤维肉瘤W31细胞在常规5%FCS(5%W31)中生长时，细胞表面hsc70的表达密度与在1%FCS(1%W31)中抑制细胞生长时几乎相同。然而，DNT细胞只裂解5%的W31，而不裂解1%的W31。由于这些观察表明快速生长的W31细胞的某些多肽AGS可能在hsc70和DNT细胞之间的相互作用中起作用，我们用三氟乙酸(TFA)提取的分子尺寸小于3000 Da的快速生长的W31肿瘤细胞的AGS来推动1%的W31细胞。我们还用从中等生长的W14肿瘤和整个胎儿组织中提取的TFA提取的AGS对1%W31进行了冲击。我们的数据表明，DNT细胞对1%的W31细胞有明显的细胞毒作用，只有从W31肿瘤中提取的TFA提取的AGS才能作用于DNT细胞。抗大鼠hsc70单抗可完全阻断这种细胞毒作用。此外，用链霉蛋白酶K处理AGS可明显抑制DNT细胞的细胞毒作用。综上所述，这些数据表明，多肽Ag和hsc70的复合体参与了hsc70和DNT细胞之间的细胞毒机制。

We previously reported that the 70kDa heat shock cognate protein-like molecule (hsc70) is expressed on the cell surface along with the neoplastic transformation of rat fibroblast and that this molecule is recognized by CD3^+, CD4^-, CD8^-, NKR-P1^-, and TCR-_<alpha> beta^- T (DNT) killer cells in an MHC class Iunrestricted fashion. We investigated the mechanism of interaction between hsc70 and DNT cells. H-ras oncogene-transformed rat fibrosarcoma W31 cells expressed hsc70 on the cell surface in almost the same density when the cells were growing in a conventional 5%FCS (5%W31) as when the cell growth was inhibited in the cultivation with 1%FCS (1%W31) . However, DNT cells lysed only 5%W31, but not 1%W31. Since these observations suggest that certain peptide Ags of the fast growing W31 cells may play a role in the interacyion between hsc70 and DNT cells, we pushed 1%W31 cells with trifluoroacetic acid (TFA) -extracted fast growing W31 tumor Ags of less than 3000 Da in molecular size. We also pulsed 1%W31 with TFA-extracted Ags from moderate growing W14 tumors and whole fetus tissues. Our data indicated that DNT cells were clearly cytotoxic to 1%W31 pushed only with TFA-extracted Ags from W31 tumors. Anti-rat hsc70 mAb completely blocked this cytotoxicity. In addtion, pronase K treatment of Ags clearly inhibited the cytotoxicity by DNT cells. Taken together, these data suggest that the complex of peptide Ag and hsc70 is involved in the cytotoxic mechanism between hsc70 and DNT cells.