[Inhibitory effects on Candida albicans of vagina cells transferred with antimicrobial peptide LL-37 and human defensin 5 recombinant plasmids].

OBJECTIVE: To evaluate the inhibitory effects on Candida albicans of vagina cells transferred with antimicrobial peptide LL-37 and human defensin 5 (HD5) recombinant plasmids and observe secretion of IL-8. METHODS: (1) The epithelial cells from female vagina were culture primarily. The pcDNA3.1(+)/HD5-EGFP and pcDNA3.1(+)/LL-37-EGFP eukaryotic recombinant plasmids were separately or jointly transferred into the fourth generation of vaginal epithelial cells. Two test groups were defined: one test group was no Candida albicans group including four subgroups which were untransferred group, HD5 group transferred with pcDNA3.1(+)/HD5-EGFP, LL-37 group transferred with pcDNA3.1(+)/LL-37-EGFP, combining transferring group transferred with pcDNA3.1(+)/HD5-EGFP and pcDNA3.1(+)/LL-37-EGFP; the other test group was with Candida albicans group which the Candida albicans were coincubated with the four subgroups described above. (2) For examination of cytokines and chemokines, at 6, 12, 24 and 48 hours, the supernatant of every group was collected. ELISA was applied to detect the levels of LL-37, HD5 and IL-8. At each time point, the growth inhibition of Candida albicans was calculated by glucose consumption testing. RESULTS: (1) The max level of LL-37, HD5 and IL-8 reached max level after being transferred for 24 hours, then showed decreasing trend. The secretion of LL-37, HD5 and IL-8 was significant higher in combining transferring group in Candida albicans group than other groups, and the secretion level of LL-37, HD5 and IL-8 was (100.16 ± 0.81) ng/ml, (58.50 ± 2.08) µg/ml and (101.03 ± 1.59) pg/ml (P < 0.01). (2) In different time point, the absorbance of each subgroup without Candida albicans declined slowly, and there were no statistically significant difference (P > 0.05), as while as in LL-37 subgroup and HD5 subgroup with Candida albicans. In group with Candida albicans, the absorbance of combining transferring subgroup were 3.210 ± 0.010, 3.150 ± 0.030, 3.099 ± 0.030 and 2.970 ± 0.040 at 6, 12, 24 and 48 hours, respectively, which was significantly higher than those in the other cells (P < 0.01), and the declined trend was the slowest. CONCLUSIONS: The antifungal ability of vaginal epithelial cell became stronger after being transferred with LL-37 and HD5 recombinant plasmids. LL-37 and HD5 could also possess immunomodulatory activity and induce chemokine IL-8 production.