ヤマニシ　ハルヨ   Haruyo Yamanishi   山西　治代    所属   川崎医科大学  医学部 基礎医学　解剖学    職種   講師
論文種別	原著
言語種別	英語
査読の有無	査読あり
表題	Keratinocyte-specific mesotrypsin contributes to the desquamation process via kallikrein activation and LEKTI degradation.
掲載誌名	正式名：The Journal of investigative dermatology ISSNコード：15231747/0022202X
掲載区分	国外
巻・号・頁	134,pp.1665-1674
著者・共著者	Miyai M, Matsumoto Y, Yamanishi H, Yamamoto-Tanaka M, Tsuboi R, Hibino T
発行年月	2014/06
概要	Kallikrein-related peptidases (KLKs) have critical roles in corneocyte desquamation and are regulated by lymphoepithelial Kazal-type inhibitor (LEKTI). However, it is unclear how these proteases are activated and how activated KLKs are released from LEKTI in the upper cornified layer. Recently, we reported cloning of a PRSS3 gene product, keratinocyte-specific mesotrypsin, from a cDNA library. We hypothesized that mesotrypsin is involved in the desquamation process, and the aim of the present study was to test this idea by examining the effects of mesotrypsin on representative desquamation-related enzymes pro-KLK5 and pro-KLK7. Incubation of mesotrypsin and these zymogens resulted in generation of the active forms. KLK activities were effectively inhibited by recombinant LEKTI domains D2, D2-5, D2-6, D2-7, D5, D6, D6-9, D7, D7-9, and D10-15, whereas mesotrypsin activity was not susceptible to these domains, and in fact degraded them. Immunoelectron microscopy demonstrated that mesotrypsin was localized in the cytoplasm of granular cells and intercellular spaces of the cornified layer. Proximity ligation assay showed close association between mesotrypsin and KLKs in the granular to cornified layers. Age-dependency analysis revealed that mesotrypsin was markedly downregulated in corneocyte extract from donors in their sixties, compared with younger donors. Collectively, our findings suggest that mesotrypsin contributes to the desquamation process by activating KLKs and degrading the intrinsic KLKs' inhibitor LEKTI.