Natural killer cells play an important role in innate immunity against Mycobacterium kansasii infection

• Main Authors: Tuan Yi Chang, 張端宜
• Other Authors: H. C. Lai
• Format: Others
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/50668211511603869897

碩士 === 長庚大學 === 醫學生物技術暨檢驗學系 === 99 === Besides Mycobacterium tuberculosis, many non-tuberculous mycobacteria (NTM) also cause pulmonary diseases, especially for immune defective AIDS patients. Therefore, the innate immunity for NTM defense is important. Natural killer (NK) cells act as the first line of animal innate immunity, especially in the aspect of anti-cancer or anti-virus transformed cells. However, the role of NK cells in defense against NTM pulmonary infection is still not clearly characterized. In this study, the role of NK cells in animal defense against M. kansasii lung infection was addressed. After infection, increase of neutrophils and macrophages infiltration in lung. This data were closely related to M. kansasii killing. Whereas depletion of NK cells toward to M. kansasii killing were not affected and mice survival were decreased. Besides, the amount of secreted cytokines such as IFN-γ, TNF-α, IL-1β, IL-23, IL-10 and IL-17 was also increased after infection. In contrast, reduced inflammation and secreted cytokines from infected animals whose NK cells were depleted by specific antibodies were observed. In concordance, preliminary data indicated decreased macrophages and polymorphonuclear cells phagocytosis ability and granuloma formation in NK cells depletion. In conclusion, our results indicate an important role of NK cells in defence against M. kansasii mouse pulmonary infection.