Janson A A, Klatser P R, van der Zee R, Cornelisse Y E, de Vries R R, Thole J E, Ottenhoff T H
Department of Immunohaematology and Bloodbank, University Hospital Leiden, The Netherlands.
J Immunol. 1991 Nov 15;147(10):3530-7.
Both protective immunity and immunopathology induced by mycobacteria are dependent on Ag-specific, CD4+ MHC class II-restricted T lymphocytes. The identification of Ag recognized by T cells is fundamental to the understanding of protective and pathologic immunity as well as to the design of effective immunoprophylaxis and immunotherapy strategies. Although some T cell clones are known to respond to recombinant mycobacterial heat shock proteins (hsp) like hsp3 65, the specificity of most T cells has remained unknown. We therefore have undertaken a specificity analysis of 48 well defined Mycobacterium leprae- and/or Mycobacterium tuberculosis-reactive (Th-1-like) T cell clones. Most clones (n = 44) were derived from different leprosy patients, and the remainder from one healthy control. Their HLA restriction molecules were DR2, DR3, DR4, DR5, DR7, DQ, or DP. T cell clones were stimulated with large numbers (n = 20 to 40) of mycobacterial SDS-PAGE-separated fractions bound to nitrocellulose. Each clone recognized a single fraction or peak with a particular Mr range. Some of the clones (n = 7) recognized the fraction that contained the hsp 65 as confirmed with the recombinant Ag. Most clones (n = 41), however, responded to Ag other than the hsp 65. Nine clones responded to a 67- to 80-kDa fraction. Five of them responded also to an ATP-purified, 70-kDa M. leprae protein, but only one of these five (that was HLA-DR2 restricted and cross-reactive with M. tuberculosis) recognized the recombinant C-terminal half (amino acids 278-621) of the M. leprae hsp 70 molecule and also recognized the recombinant M. tuberculosis hsp 70. We therefore have used the 5' part of the M. leprae hsp 70 gene that we have cloned recently. This fragment (that encodes amino acids 6-279) was indeed recognized by the other four M. leprae-specific T cells that were all HLA-DR3 restricted and did not cross-react with the highly homologous (95%) M. tuberculosis hsp 70. These results suggest that this novel fragment is a relevant T cell-stimulating Ag for leprosy patients. A panel of other recombinant Ag, including hsp 18 was tested. The majority of T cell clones appeared to recognize antigenic fractions distinct from hsp. In conclusion, T cells of leprosy patients see a large variety of different Ag including non-hsp, and one newly recognized moiety is the N-terminal M. leprae hsp 70 fragment.(ABSTRACT TRUNCATED AT 400 WORDS)
分枝杆菌诱导的保护性免疫和免疫病理反应均依赖于抗原特异性、MHC II类分子限制的CD4⁺T淋巴细胞。确定T细胞识别的抗原对于理解保护性和病理性免疫以及设计有效的免疫预防和免疫治疗策略至关重要。虽然已知一些T细胞克隆可对重组分枝杆菌热休克蛋白（hsp）如hsp365产生反应，但大多数T细胞的特异性仍不清楚。因此，我们对48个明确界定的麻风分枝杆菌和/或结核分枝杆菌反应性（Th-1样）T细胞克隆进行了特异性分析。大多数克隆（n = 44）来自不同的麻风病患者，其余来自一名健康对照。它们的HLA限制分子为DR2、DR3、DR4、DR5、DR7、DQ或DP。用大量（n = 20至40）与硝酸纤维素结合的经SDS-PAGE分离的分枝杆菌级分刺激T细胞克隆。每个克隆识别一个单一的级分或具有特定分子量范围的峰。一些克隆（n = 7）识别含有hsp 65的级分，这已通过重组抗体验证。然而，大多数克隆（n = 41）对hsp 65以外的抗原产生反应。9个克隆对67至80 kDa的级分产生反应。其中5个也对ATP纯化的70 kDa麻风分枝杆菌蛋白产生反应，但这5个克隆中只有1个（其受HLA-DR2限制且与结核分枝杆菌交叉反应）识别麻风分枝杆菌hsp 70分子的重组C末端半段（氨基酸278 - 621），并且也识别重组结核分枝杆菌hsp 70。因此，我们使用了最近克隆的麻风分枝杆菌hsp 70基因的5'部分。这个片段（编码氨基酸6 - 279）确实被其他4个麻风分枝杆菌特异性T细胞识别，这些T细胞均受HLA-DR3限制且不与高度同源（95%）的结核分枝杆菌hsp 70交叉反应。这些结果表明，这个新片段是麻风病患者相关的T细胞刺激抗原。还测试了一组其他重组抗原，包括hsp 18。大多数T细胞克隆似乎识别与hsp不同的抗原级分。总之，麻风病患者的T细胞可识别多种不同的抗原，包括非hsp，并且一个新识别的部分是麻风分枝杆菌hsp 70的N末端片段。（摘要截断于400字）
