Superoxide anions produced by Streptococcus pyogenes group A-stimulated keratinocytes are responsible for cellular necrosis and bacterial growth inhibition:

Innate Immunity

ElodieRegnier¹ 

关键词: ROS;    Streptococcus pyogenes;    cellulitis;    cell death;    inflammation;   

DOI  :  10.1177/1753425915619476

学科分类：生物科学（综合）

来源: Sage Journals

【 摘 要 】

Gram-positive Streptococcus pyogenes (group A Streptococcus or GAS) is a major skin pathogen and interacts with keratinocytes in cutaneous tissues. GAS can cause diverse suppurative and inflammatory infections, such as cellulitis, a common acute bacterial dermo-hypodermitis with a high morbidity. Bacterial isolation yields from the lesions are low despite the strong local inflammation observed, raising numerous questions about the pathogenesis of the infection. Using an in vitro model of GAS-infected keratinocytes, we show that the major ROS produced is the superoxide anion (O2-), and that its production is time- and dose-dependent. Using specific modulators of ROS production, we show that O2- is mainly synthesized by the cytoplasmic NADPH oxidase. Superoxide anion production leads to keratinocyte necrosis but incomplete inhibition of GAS growth, suggesting that GAS may be partially resistant to the oxidative burst. In conclusion, GAS-stimulated keratinocytes are able to develop an innate immune response ...

【 授权许可】

CC BY