-induced keratitis is one of the most severe and challenging forms of corneal infection, owing to its associated intense inflammatory reactions leading to corneal necrosis and dense corneal scar with loss of vision. Since mesenchymal stem cells (MSCs) are reported to possess antimicrobial and immunomodulatory properties, they can be tested as an adjuvant treatment along with the antibiotics which are the current standard of care. This study aims to investigate the anti-bacterial and immunomodulatory roles of human bone marrow MSC-derived conditioned medium (MSC-CM) in -infected human corneal epithelial cells (HCECs) The effect of MSC-CM on the growth of clinical isolates of was evaluated by colony-forming unit assay. The expression of inflammatory cytokines (IL-6 and TNF-α) and an antimicrobial peptide (Lipocalin 2) in lipopolysaccharide-treated MSCs and HCECs was analyzed through ELISA. Corneal epithelial repair following infection with was studied through scratch assay. Compared to control ( (5*10) incubated in DMEM (1 ml) at 37 °C for 16 h), MSC-CM significantly: i) inhibits the growth of 159*10 vs. 104*10 CFU/ml), ii) accelerates corneal epithelial repair following infection with (9% vs. 24% closure of the wounded area after 12 h of infection) and iii) downregulates the lipopolysaccharide-induced expression of IL-6, TNF-α and Lipocalin 2 in HCECs. A combination of MSC-CM with an antibiotic, Ciprofloxacin moderately regulated the expression of IL-6, TNF-α, and Lipocalin 2. MSC-CM holds promise as an adjunctive therapeutic approach for -induced corneal epithelial damage.

中文翻译：

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基于间充质干细胞的辅助疗法治疗铜绿假单胞菌引起的角膜炎：概念验证体外研究

引起的角膜炎是最严重和最具挑战性的角膜感染形式之一，因为其相关的强烈炎症反应导致角膜坏死和致密角膜疤痕并导致视力丧失。据报道，间充质干细胞 (MSC) 具有抗菌和免疫调节特性，因此可以将它们与当前标准治疗的抗生素一起作为辅助治疗进行测试。本研究旨在探讨人骨髓间充质干细胞来源的条件培养基（MSC-CM）在感染的人角膜上皮细胞（HCEC）中的抗菌和免疫调节作用。通过菌落形成单位测定进行评估。通过 ELISA 分析脂多糖处理的 MSC 和 HCEC 中炎症细胞因子（IL-6 和 TNF-α）和抗菌肽（Lipocalin 2）的表达。通过划痕试验研究了感染后的角膜上皮修复。与对照（(5*10) 在 DMEM (1 ml) 中于 37 °C 孵育 16 小时）相比，MSC-CM 显着：i) 抑制生长 159*10 vs. 104*10 CFU/ml)，ii ) 加速感染后的角膜上皮修复（感染 12 小时后受伤区域闭合 9% vs. 24%），iii) 下调 HCEC 中脂多糖诱导的 IL-6、TNF-α 和 Lipocalin 2 的表达。 MSC-CM 与抗生素环丙沙星的组合可适度调节 IL-6、TNF-α 和脂质运载蛋白 2 的表达。MSC-CM 有望成为治疗角膜上皮损伤的辅助治疗方法。