Nagabhushanam V, Praszkier J, Cheers C
Department of Microbiology and Immunology, University of Melbourne, Victoria, Australia.
Immunol Cell Biol. 2001 Oct;79(5):454-61. doi: 10.1046/j.1440-1711.2001.01032.x.
The heat shock protein Hsp65 has been characterized previously in several mycobacterial species. This is the first report of the complete sequence of the coding region of the Mycobacterium avium homologue. The sequence was highly homologous to the Hsp65 of other mycobacterial species, as well as being related closely to the murine and human homologues. Recombinant Hsp65 (rHsp65) was expressed in Escherichia coli to high levels and the recombinant protein tested for its immunogenicity in a murine model of M. avium infection. Although mice infected with M. avium produced antibodies that reacted with rHsp65, they showed low proliferative T-cell responses and no cytokine production in response to the same antigen. However, immunization with rHsp65 in the adjuvant dimethydioctadecylammonium bromide (DDA), induced T cells that responded to native Hsp65 with proliferation and IFN-gamma production, indicating that the recombinant and native forms of the protein were antigenically similar. Therefore, the findings indicate that Hsp65 is not a dominant T-cell antigen during M. avium infection.
热休克蛋白Hsp65先前已在几种分枝杆菌中得到鉴定。本文首次报道了鸟分枝杆菌同源物编码区的完整序列。该序列与其他分枝杆菌物种的Hsp65高度同源，并且与小鼠和人类的同源物也密切相关。重组Hsp65（rHsp65）在大肠杆菌中高水平表达，并在鸟分枝杆菌感染的小鼠模型中测试该重组蛋白的免疫原性。尽管感染鸟分枝杆菌的小鼠产生了与rHsp65反应的抗体，但它们对相同抗原的T细胞增殖反应较低且无细胞因子产生。然而，用rHsp65在佐剂二甲基二十八烷基溴化铵（DDA）中免疫诱导的T细胞，对天然Hsp65有增殖反应并产生γ干扰素，表明该蛋白的重组形式和天然形式在抗原性上相似。因此，研究结果表明Hsp65在鸟分枝杆菌感染期间不是主要的T细胞抗原。
