GAMMA DELTA T CELLS AND TUBERCULOSIS

点击翻译按钮获取中文摘要

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Little is known about the immune distribution and localization of antigen-specific T cells in mucosal interfaces of tissues/organs during infection of humans. In this study, we made use of a macaque model of Mycobacterium tuberculosis infection to assess phosphoantigen-specific VGAMMA2VDELTA2 cells regarding their tissue distribution, anatomical localization, and correlation with the presence or absence of tuberculosis (TB) lesions in lymphoid and nonlymphoid organs/tissues in the progression of severe pulmonary TB. Progression of pulmonary M. tuberculosis infection generated diverse distribution patterns of VGAMMA2VDELTA2 cells, with remarkable accumulation of these cells in lungs, bronchial lymph nodes, spleens, and remote nonlymphoid organs but not in blood. Increased numbers of VGAMMA2VDELTA2 cells in tissues were associated with M. tuberculosis infection but were independent of the severity of TB lesions. In lungs with apparent TB lesions, VGAMMA2VDELTA2 cells were present within TB granulomas. In extrathoracic organs, VGAMMA2VDELTA2 cells were localized in the interstitial compartment of nonlymphoid tissues, and the interstitial localization was present despite the absence of detectable TB lesions. Finally, VGAMMA2VDELTA2 cells accumulated in tissues appeared to possess cytokine production function, since granzyme B was detectable in the Gamma/deltaT cells present within granulomas. Thus, clonally expanded VGAMMA2VDELTA2 cells appeared to undergo trans-endothelial migration, interstitial localization, and granuloma infiltration as immune responses to M. tuberculosis infection.