Interaction between Candida albicans and Cultured Human Keratinocytes / 中华皮肤科杂志

Objective To study the morphological,biologic response of cultured human keratin ocytes to Candida albicans and the molecular mechanism.Methods ①A yeast form of C.albicans was added t o a monolayer of keratinocytes.The adherent organisms were observed by scanning and transmission electron mi-croscope at different incubation periods.Boiled C.albicans and latex beads of a similar size(3.2?m)were also inoculated for comparison.②The effect of supernatant from the co-culture of keratinocytes with inta ct C.albicans on keratinocyte growth was measured by the fluorescence intensity and cell count.③Keratinocytes were incubated with C.albicans or latex beads,and the level of cytok ine in the keratinocytes and supernatant were measured with enzyme -linked im munosorbent assay kits.Results①The number of adherent C.albicans increased with the lapse of time,whi le boiled C.albicans did not adhere at all.Many latex bead s adhered to the keratinocytes,and were then easily phagocytised.Fibril -like structu res stretched from the keratinocyte s adhered to the organisms or latex beads.②The conditioned medium of 50%concen tration significantly promote cell growth,while that with boiled C.albicans or latex beads moderately stimulate d keratinocyte growth.③Ker-atinocytes treated with intact C.albicans had significantly higher level of IL-1?in the supernatant but lower in the cell extract.Both TGF -?and bFGF increased either in the medi a or in the extract.Conclusion These results suggest that keratinocytes have non -specific phagocytic activ ity.C.albicans are able to adhere to ker-atinocytes and stimulate the release of various cytokines from keratinocytes,which may induce an inflammatory reaction and cell growth.

Experimental Study of Antifungal Effect of Povidone Iodine Solution on Candida Albicans / 中华皮肤科杂志

The effect of povidone iodine solution(PIS)on the metabolic activity of Candida albi- cans and the effect of PIS treated C.altn'cans to cultured human keratinocytes were studied by using the Alamar blue fluorescence assay.It was found that PIS inhibited the metabolic activity of Candida albi- cans with a dose-dependent manner,and that the LD_(50)of PIS for Candida albicans is 0.075%.After treating for 30 min by 2% PIS/PBS(-),Candida albicans almost lost the adherence and invasion to the cultured human keratinocytes,the wall of yeast cells became uneven and shrunken,the intracellular structures became obviously indistinct,and the yeasts could not develop to hypha form.Candida albi- cans,treated with 2% PIS in PBS(-)for 30 min or with 10% PIS Sabouraud's liquid medium for 33 hr,did not form colony when it was inoculated to Sabouraud's dextrose agar.This result suggests that the fungicidal effective of PIS is influenced by its solvent.