Department of General Internal Medicine, National Hospital Organization Tokyo Medical Center, Meguro-ku, Tokyo, Japan.
Laboratory of Infectious Diseases, Graduate School of Infection Control Sciences and Kitasato Institute for Life Sciences, Kitasato University, Minato-ku, Tokyo, Japan.
Ann Lab Med. 2018 May;38(3):189-195. doi: 10.3343/alm.2018.38.3.189.
Clostridium difficile is a major causative agent of antibiotic-associated diarrhea and has become the most common pathogen of healthcare-associated infection worldwide. The pathogenesis of C. difficile infection (CDI) is mediated by many factors such as colonization involving attachment to host intestinal epithelial cells, sporulation, germination, and toxin production. Bacterial cell surface components are crucial for the interaction between the bacterium and host cells. C. difficile has two distinct surface layer proteins (SLPs): a conserved high-molecular-weight SLP and a highly variable low-molecular-weight SLP. Recent studies have shown that C. difficile SLPs play roles not only in growth and survival, but also in adhesion to host epithelial cells and induction of cytokine production. Sequence typing of the variable region of the slpA gene, which encodes SLPs, is one of the methods currently used for typing C. difficile. SLPs have received much attention in recent years as vaccine candidates and new therapeutic agents in the treatment of C. difficile-associated diseases. Gaining mechanistic insights into the molecular functions of C. difficile SLPs will help advance our understanding of CDI pathogenesis and the development of vaccines and new therapeutic approaches. In this review, we summarize the characteristics and immunological roles of SLPs in C. difficile.
艰难梭菌是抗生素相关性腹泻的主要病原体，已成为全球最常见的医源性感染病原体。艰难梭菌感染（CDI）的发病机制是由多种因素介导的，如定植涉及与宿主肠道上皮细胞的附着、孢子形成、发芽和毒素产生。细菌细胞表面成分对于细菌与宿主细胞之间的相互作用至关重要。艰难梭菌有两种不同的表面层蛋白（SLPs）：保守的高分子量 SLP 和高度可变的低分子量 SLP。最近的研究表明，艰难梭菌 SLPs 不仅在生长和存活中发挥作用，而且在与宿主上皮细胞的黏附和诱导细胞因子产生中也发挥作用。编码 SLPs 的 slpA 基因可变区的序列分型是目前用于艰难梭菌分型的方法之一。近年来，SLPs 作为疫苗候选物和治疗艰难梭菌相关疾病的新型治疗药物备受关注。深入了解艰难梭菌 SLPs 的分子功能将有助于我们深入了解 CDI 的发病机制以及疫苗和新治疗方法的开发。在这篇综述中，我们总结了 SLP 在艰难梭菌中的特征和免疫学作用。
