Defensins couple dysbiosis to primary immunodeficiency in Crohn's disease

Antimicrobial peptides,including defensins,are essential effectors in host defence and in the maintenance of immune homeostasis.Clinical studies have linked the defective expression of both α-and β-defensin to the reduced killing of certain microorganisms by the intestinal mucosa of patients suffering from ileal and colonic Crohn's disease(CD),respectively.Only recently have the events leading to defective expression of defensins in CD been further elucidated,and are discussed herein.These events may account for CD-associated alterations in the microbiome and may subsequently precipitate the development of granulomatous inflammatory lesions in genetically-predisposed patients.We also address how these discoveries may pave the way for the development of a molecular medicine aimed at restoring gut barrier function in CD.

InlA和InlB介导单核细胞增生李斯特菌入侵宿主细胞分子机制的研究进展

单核细胞增生李斯特菌(Listeria monocytogenes)是一种革兰氏阳性食源性致病菌。在造成宿主食源性感染的过程中,单核细胞增生李斯特菌能凭借其独特的表面蛋白入侵宿主的非吞噬细胞。内化素蛋白家族(Internalins)是介导单核细胞增生李斯特菌入侵宿主非吞噬细胞的主要因子。本文根据国内外一些最新的研究成果,结合作者近几年的工作,综述了在侵染宿主的过程中,单核细胞增生李斯特菌主要的内化素蛋白InlA和InlB介导细菌入侵宿主细胞的分子机制,以期为阐明食源性致病菌致病机理、预防和治疗食源性疾病提供理论基础。