Paneth cells secrete lysozyme via secretory autophagy during bacterial infection of the intestine.
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ABSTRACT:
SUBMITTER: Bel S
PROVIDER: S-EPMC5702267 | biostudies-literature | 2017 Sep
REPOSITORIES: biostudies-literature
Publications
Paneth cells secrete lysozyme via secretory autophagy during bacterial infection of the intestine.
Bel Shai S Pendse Mihir M Wang Yuhao Y Li Yun Y Ruhn Kelly A KA Hassell Brian B Leal Tess T Winter Sebastian E SE Xavier Ramnik J RJ Hooper Lora V LV
Science (New York, N.Y.) 20170727 6355
Intestinal Paneth cells limit bacterial invasion by secreting antimicrobial proteins, including lysozyme. However, invasive pathogens can disrupt the Golgi apparatus, interfering with secretion and compromising intestinal antimicrobial defense. Here we show that during bacterial infection, lysozyme is rerouted via secretory autophagy, an autophagy-based alternative secretion pathway. Secretory autophagy was triggered in Paneth cells by bacteria-induced endoplasmic reticulum (ER) stress, required ...[more]
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2010-06-09 | E-GEOD-2958 | biostudies-arrayexpress
Project description:Paneth cells of intestinal crypts contribute to host defense by producing antimicrobial peptides that are packaged as granules for secretion into the crypt lumen. Here, we provide evidence using light and electron microscopy that postsecretory Paneth cell granules undergo limited dissolution and accumulate within the intestinal crypts of cystic fibrosis (CF) mice. On the basis of this finding, we evaluated bacterial colonization and expression of two major constituents of Paneth cells, i.e., {alpha}-defensins (cryptdins) and lysozyme, in CF murine intestine. Paneth cell granules accumulated in intestinal crypt lumens in both untreated CF mice with impending intestinal obstruction and in CF mice treated with an osmotic laxative that prevented overt clinical symptoms and mucus accretion. Ultrastructure studies indicated little change in granule morphology within mucus casts, whereas granules in laxative-treated mice appear to undergo limited dissolution. Protein extracts from CF intestine had increased levels of processed cryptdins compared with those from wild-type (WT) littermates. Nonetheless, colonization with aerobic bacteria species was not diminished in the CF intestine and oral challenge with a cryptdin-sensitive enteric pathogen, Salmonella typhimurium, resulted in greater colonization of CF compared with WT intestine. Modest downregulation of cryptdin and lysozyme mRNA in CF intestine was shown by microarray analysis, real-time quantitative PCR, and Northern blot analysis. Based on these findings, we conclude that antimicrobial peptide activity in CF mouse intestine is compromised by inadequate dissolution of Paneth cell granules within the crypt lumens. Keywords: other
2005-07-18 | GSE2958 | GEO