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目的：研究抗菌肽LL-37通过促进阴道上皮细胞免疫因子的分泌抑制假丝酵母菌的作用。方法（1）构建LL-37原核表达载体pET-Duet/LL-37并在大肠埃希菌M15中诱导表达。对所表达的LL-37融合蛋白进行纯化及鉴定，并用K-B纸片法初步验证LL-37纯化蛋白的抗真菌活性。（2）纯化的LL-37蛋白加入到与假丝酵母菌共培养的人阴道上皮细胞[即外阴阴道假丝酵母菌病（VVC）阴道上皮细胞模型]中，并分为实验组与对照组（不加LL-37纯化蛋白），采用葡萄糖消耗法观察抑菌效果[以吸光度（A）值表示]。采用ELISA方法检测不同时间点干扰素γ（IFN-γ）、白细胞介素10（IL-10）水平及IFN-γ/IL-10比值的变化。结果（1）诱导表达的LL-37融合蛋白的浓度为433.92μg/ml，纯度达96%。K-B纸片法初步证实了LL-37纯化蛋白具有一定的抗真菌活性。（2）LL-37重组蛋白可明显抑制假丝酵母菌生长，实验组各时间点A值明显高于对照组（分别为：12 h：3.008±0.003、2.967±0.003；24 h：2.941±0.003、2.601±0.003；48 h：2.893±0.004、2.409±0.003），分别比较，差异均有统计学意义（P<0.01），并且随时间进展的下降趋势较对照组缓慢。两组IFN-γ、IL-10分泌水平均呈现先升后降的趋势，于24 h达高峰[实验组分别为：（104.00±1.07）、（108.4±0.7）pg/ml；对照组分别为：（85.17±0.28）、（151.6±0.6）pg/ml]。各时间点比较，实验组IFN-γ水平于24 h时明显高于对照组（P<0.01）；各时间点的IL-10水平均低于对照组（P<0.01），且IFN-γ/IL-10比值均高于对照组（P<0.01）。结论（1）LL-37重组蛋白对假丝酵母菌具有明显的抑制作用。（2）LL-37重组蛋白通过影响IFN-γ、IL-10等免疫因子的分泌，调整阴道上皮细胞局部免疫，增强抵抗假丝酵母菌感染的能力。

Objective To study the inhibitory effect of antimicrobial peptide LL-37 on Candida albicans through its ability to promote the secretion of immune factors by vaginal epithelial cells. Methods (1) LL-37 prokaryotic expression vector pET-Duet/LL-37 was constructed and its expression was induced in Escherichia coli M15. The expressed LL-37 fusion protein was purified and identified by western blot. Antifungal activity of the purified protein was initially identified by Kirby-Bauer (K-B) method. (2) Purified LL-37 protein was added to human vaginal epithelial cells co-cultured with Candida, and inhibitory effect on Candida growth was determined by the glucose consumption method. Interferon γ (IFN-γ), interleukin 10 (IL-10) concentration and IFN-γ/IL-10 ratio were measured by ELISA at different time points. Results (1) LL-37 fusion protein was purified to 96% purity at a concentration of 433.92 μg/ml, and was shown to possess anti-fungal activity confirmed by the K-B method. (2) A Candida-vaginal epithelial cells co-culture system was successfully constructed. LL-37 recombinant protein inhibited the growth of Candida with absorbance values significantly higher in the treatment group compared to the control group at all measured&nbsp;time points (12-hour:3.008±0.003 versus 2.967±0.003, 24-hour:2.941±0.003 versus 2.601±0.003, 48-hour:2.893 ± 0.004 versus 2.409 ± 0.003; all P<0.01). Furthermore, the rate of decrease was also much slower compared to the control group. In both control and experimental groups, IFN-γ and IL-10 secretion levels were observed to rise at first peaking at 24 hours and subsequently decrease. For each time period, IFN-γconcentration in the experimental group was significantly higher at 24 hours compared to the control group [(104.00 ± 1.07) versus (85.17 ± 0.28) pg/ml, P<0.01]. In contrast, IL-10 concentrations were significantly lower than the control group at all time points (P<0.01). IFN-γ/IL-10 ratio was also observed to be significantly higher than the control group at all measured time points (P<0.01). Conclusions (1) Recombinant protein LL-37 could significantly inhibit the growth of Candida. (2) By influencing the secretion of immune factors such as IFN-γ, IL-10, etc, recombinant protein LL-37 is able to adjust vaginal epithelial cells local immunity, and enhance resistance to Candida infection.