Emoto M, Naito T, Nakamura R, Yoshikai Y
Laboratory of Germfree Life, Research Institute for Disease Mechanism and Control, Nagoya University School of Medicine, Japan.
J Immunol. 1993 Apr 15;150(8 Pt 1):3411-20.
Ity gene, which is believed to be a single gene on proximal mouse chromosome 1, determines susceptibility to Salmonella infection. We have recently demonstrated that the gamma delta T cells specific for purified protein derivative appear at the early stage after infection with Salmonella choleraesuis strain 31N-1 (avirulent strain) in mice. In the present study, we compared the appearance of the gamma delta T cells in Ityr and Itys mice after infection with S. choleraesuis in an attempt to elucidate the role of the gamma delta T cells in the in vivo effect of the Ity locus on murine salmonellosis. The numbers of gamma delta T cells in the peritoneal cavity and liver were significantly larger in DBA/2 (Ityr) mice than those in BALB/c (Itys) mice after infection with a sublethal dose of S. choleraesuis. C.D2 Ityr mice, which are BALB/c mice with Ityr allele, also showed a significant increase in the number of the gamma delta T cells at the early stage after infection. Similar results in different appearances of the gamma delta T cells could be obtained between BALB/c and DBA/2 mice after infection with Mycobacterium bovis, bacillus Calmette-Guérin. The peritoneal adherent cells of DBA/2 mice infected with S. choleraesuis, which expressed a large amount of heat shock/stress protein (hsp) homologous to the mycobacterial 65-kDa hsp, induced significantly higher level of expansion of the peritoneal gamma delta T cells in normal mice in vivo and in vitro than did those of BALB/c mice infected with S. choleraesuis, which expressed a lesser amount of the hsp. These results suggest that the Ity locus may be closely related to the expression of hsp by macrophages after infection with Salmonella, which in turn stimulate the gamma delta T cells in the host during an early phase of salmonellosis.
Ity基因被认为是小鼠近端1号染色体上的一个单一基因，它决定了对沙门氏菌感染的易感性。我们最近证明，在小鼠感染猪霍乱沙门氏菌31N - 1菌株（无毒菌株）后的早期阶段，出现了对纯化蛋白衍生物特异的γδT细胞。在本研究中，我们比较了感染猪霍乱沙门氏菌后Ityr和Itys小鼠中γδT细胞的出现情况，试图阐明γδT细胞在Ity基因座对小鼠沙门氏菌病的体内效应中的作用。用亚致死剂量的猪霍乱沙门氏菌感染后，DBA/2（Ityr）小鼠腹腔和肝脏中的γδT细胞数量明显多于BALB/c（Itys）小鼠。携带Ityr等位基因的BALB/c小鼠C.D2 Ityr在感染后的早期阶段，γδT细胞数量也显著增加。在用牛型结核杆菌卡介苗感染后，BALB/c和DBA/2小鼠之间也能得到γδT细胞不同出现情况的类似结果。感染猪霍乱沙门氏菌的DBA/2小鼠的腹腔黏附细胞表达大量与结核杆菌65-kDa热休克/应激蛋白（hsp）同源的热休克/应激蛋白，与感染猪霍乱沙门氏菌且表达较少该热休克蛋白的BALB/c小鼠相比，在体内和体外均能诱导正常小鼠腹腔γδT细胞产生显著更高水平的扩增。这些结果表明，Ity基因座可能与感染沙门氏菌后巨噬细胞热休克蛋白的表达密切相关，进而在沙门氏菌病的早期阶段刺激宿主中的γδT细胞。
