Biozentrum, University of Basel, Basel, Switzerland.
Division of Experimental Virology, Department Biomedicine-Haus Petersplatz, University of Basel, Basel, Switzerland.
J Immunol. 2024 Sep 1;213(5):553-558. doi: 10.4049/jimmunol.2400045.
The importance of unconventional T cells for mucosal immunity is firmly established but for systemic bacterial infection remains less well defined. In this study, we explored the role of various T cell subsets in murine Bartonella infection, which establishes persistent bacteremia unless controlled by antibacterial Abs. We found that αβ T cells are essential for Ab production against and clearance of B. taylorii, whereas MHC class I (MHC-I)- or MHC class II (MHC-II)-deficient mice eliminated B. taylorii infection with normal kinetics. Similarly, animals lacking either CD1d or MR1 suppressed bacteremia with normal kinetics. Interestingly, mice with a combined deficiency of either MHC-II and CD1d or MHC-II and MR1 failed to clear the infection, indicating that the combination of CD1d- and MR1-restricted T cells can compensate for the lack of MHC-II in this model. Our data document a previously underappreciated contribution of unconventional T cells to the control of systemic bacterial infection, supposedly as helper cells for antibacterial Ab production.
非传统 T 细胞对于黏膜免疫的重要性已得到充分证实，但对于全身细菌感染的作用仍定义不明确。在这项研究中，我们探讨了各种 T 细胞亚群在鼠贝氏疏螺旋体感染中的作用，这种感染会导致持续性菌血症，除非通过抗菌抗体（Ab）加以控制。我们发现，αβ T 细胞对于产生针对 B. taylorii 的抗体和清除该菌至关重要，而 MHC Ⅰ类（MHC-I）或 MHC Ⅱ类（MHC-II）缺陷小鼠以正常的动力学消除 B. taylorii 感染。同样，缺乏 CD1d 或 MR1 的动物也以正常的动力学抑制菌血症。有趣的是，同时缺乏 MHC-II 和 CD1d 或 MHC-II 和 MR1 的小鼠无法清除感染，表明在该模型中，CD1d 和 MR1 限制的 T 细胞的组合可以弥补 MHC-II 的缺乏。我们的数据记录了非传统 T 细胞对于控制全身细菌感染的先前被低估的作用，推测其作为产生抗菌抗体的辅助细胞。
