RRC ID 61348
著者 Mohankumar V, Ramalingam S, Chidambaranathan GP, Prajna L.
タイトル Autophagy induced by type III secretion system toxins enhances clearance of Pseudomonas aeruginosa from human corneal epithelial cells.
ジャーナル Biochem Biophys Res Commun
Abstract Corneal ulcers caused by Pseudomonas aeruginosa may lead to severe visual disability due to impaired bacterial clearance from corneal tissues. Our purpose was to study the role of autophagy in the intracellular clearance of P. aeruginosa from human corneal epithelial cells (HCET) and its regulation by the bacterial type III secretion system (T3SS) toxins. Nine different corneal ulcer isolates of P. aeruginosa, PAO1 and T3SS mutants of PAO1 were used to infect HCET cells. Induction of autophagy (Immunofluorescence and Western blot) and pro-inflammatory gene expression (real time PCR) by P. aeruginosa and the role of autophagy in intracellular bacterial clearance were studied in the context of T3SS genotypes. The clinical isolates and PAO1 induced autophagy irrespective of the T3SS genotype, whereas the T3SS mutants were relatively defective in inducing autophagy and becn1 gene expression. External induction of autophagy significantly reduced the intracellular load of P. aeruginosa strains that were associated with worst clinical outcomes. The T3SS negative isolate and PAO1ΔexoST were less sensitive to pharmacological modulation of autophagy and had relatively higher replication potential, suggesting a possible mechanism of bacterial survival in the absence of T3SS toxins. Overall, our results highlight a selective role for autophagy in bacterial clearance from corneal epithelial cells and emphasize the pro-autophagic role of bacterial toxins in the context of corneal ulcers.
巻・号 503(3)
ページ 1510-1515
公開日 2018-9-10
DOI 10.1016/j.bbrc.2018.07.071
PII S0006-291X(18)31567-5
PMID 30031608
MeSH Autophagy / drug effects* Bacterial Toxins / genetics Bacterial Toxins / pharmacology* Epithelium, Corneal / cytology Epithelium, Corneal / drug effects* Epithelium, Corneal / microbiology* Humans Pseudomonas aeruginosa / drug effects* Pseudomonas aeruginosa / isolation & purification Type III Secretion Systems / chemistry* Type III Secretion Systems / genetics
IF 2.985
リソース情報
ヒト・動物細胞 HCE-T(RCB2280)