金黄色葡萄球菌通过自分泌的 IL-1alpha 信号通路刺激角质形成细胞中中性粒细胞趋化因子的表达。
Staphylococcus aureus stimulates neutrophil targeting chemokine expression in keratinocytes through an autocrine IL-1alpha signaling loop.
机构信息
Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA.
出版信息
J Invest Dermatol. 2010 Jul;130(7):1866-76. doi: 10.1038/jid.2010.37. Epub 2010 Feb 25.
Staphylococcus aureus is a significant human pathogen that can colonize the skin. Neutrophils are well known to be involved in clearance of the bacterium. This study focused on exploring the role that human keratinocytes have as first responders to bacterial challenges. IL-1alpha and IL-1beta increased mRNA production and protein secretion of the neutrophil chemotactic CXCL1, CXCL2, and IL-8 in keratinocytes. S. aureus and the bacterial cell wall components lipoteichoic acid (LTA) and peptidoglycan (PGN) induced similar expression profiles in a Toll-like receptor (TLR)-2-dependent manner. Interestingly, the S. aureus-induced mRNA levels peaked at later time points than those induced by IL-1. The S. aureus-activated chemokine production was preceded by significant IL-1alpha and IL-1beta secretion. Expression of IL-1alpha was significantly higher than that of IL-1beta. Inhibition of IL-1RI using neutralizing antibodies revealed that S. aureus-derived LTA and PGN-induced chemokine expression requires IL-1RI engagement. Surprisingly, we further found that chemokine secretion is dependent upon endocrine IL-1alpha, but not IL-1beta, signaling. Our data show that the innate immune response of keratinocytes is regulated differently than those of other cell types. This may represent a fail-safe system that protects the host against genetic variation and immune evasion mechanisms developed by pathogens.
金黄色葡萄球菌是一种重要的人类病原体,可以定植在皮肤表面。众所周知,中性粒细胞参与了细菌的清除。本研究旨在探索人类角质形成细胞作为细菌挑战的第一反应者的作用。IL-1alpha 和 IL-1beta 增加了中性粒细胞趋化因子 CXCL1、CXCL2 和 IL-8 的 mRNA 产生和蛋白分泌。金黄色葡萄球菌和细菌细胞壁成分脂磷壁酸(LTA)和肽聚糖(PGN)以 Toll 样受体(TLR)-2 依赖的方式诱导相似的表达谱。有趣的是,金黄色葡萄球菌诱导的 mRNA 水平在时间上晚于 IL-1 诱导的水平达到峰值。金黄色葡萄球菌激活的趋化因子产生之前伴随着显著的 IL-1alpha 和 IL-1beta 分泌。IL-1alpha 的表达明显高于 IL-1beta。使用中和抗体抑制 IL-1RI 表明,金黄色葡萄球菌衍生的 LTA 和 PGN 诱导的趋化因子表达需要 IL-1RI 的参与。令人惊讶的是,我们进一步发现趋化因子的分泌依赖于内分泌 IL-1alpha,而不是 IL-1beta,信号。我们的数据表明,角质形成细胞的固有免疫反应与其他细胞类型的固有免疫反应不同。这可能代表了一种故障安全系统,可保护宿主免受病原体遗传变异和免疫逃逸机制的影响。