Anti-biofilm activity of chlorhexidine digluconate against Candida albicans vaginal isolates.

OBJECTIVES: Recurrent vulvovaginal candidiasis (RVVC) causes significant morbidity. Candida albicans is the main pathogen associated with both sporadic and recurrent candidiasis. Due to unsatisfactory treatment effect, the impact of chlorhexidine digluconate and fluconazole alone or in combination on C. albicans and biofilm was investigated. METHODS: Vaginal C. albicans isolates from 18 patients with recurrent candidiasis and commensals from 19 asymptomatic women were isolated by culture. Crystal violet, XTT and colony forming unit assay were used to analyze the effect of chlorhexidine digluconate and fluconazole on growth of C. albicans, formation of new and already established, mature, biofilm. RESULTS: Fluconazole reduced the growth of planktonic C. albicans. However, in established biofilm, fluconazole had no effect on the candida cells and was not able to disperse and reduce the biofilm. By contrast, chlorhexidine digluconate had a direct killing effect on C. albicans grown both planktonically and in biofilm. Chlorhexidine digluconate also dispersed mature biofilm and inhibited formation of new biofilm. No major differences were observed between commensal isolates and candida causing recurrent vulvovaginitis with respect to biofilm or growth after chlorhexidine digluconate treatment. CONCLUSION: Biofilm is a problem in patients with recurrent vulvovaginal candidiasis reducing the effect of antifungal treatment. Development of new treatment strategies are urgently needed to decrease the recurrences. In already established biofilm, chlorhexidine digluconate dispersed the biofilm and was more effective in eradicating candida compared to fluconazole. Future treatment strategy may thus be a combination of chlorhexidine digluconate and fluconazole and prophylactic use of chlorhexidine digluconate to prevent biofilm formation and restrict infections.

Expression of Psoriasin in Human Papillomavirus-Induced Cervical High-Grade Squamous Intraepithelial Lesions.

OBJECTIVES: Persistent infection with human papillomavirus causes cervical high-grade squamous intraepithelial lesions (HSILs). The role of antimicrobial peptides (AMPs) in premalignant and malignant transformation is not fully understood. In this study, we examined the expression of human ß-defensin 1 (HBD-1), HBD-2, HBD-3, LL37, psoriasin, and interleukin 8 (IL-8) in women with HSIL before and 6 months after surgery. MATERIALS AND METHODS: Biopsies and secretion samples from the cervical canal were collected from 19 patients with HSIL and 14 healthy controls. The mRNA expression of HBD-1, HBD-2, HBD-3, LL37, psoriasin, and IL-8 was analyzed before and 6 months after surgery excision using reverse transcriptase real time polymerase chain reaction. For protein analyses, ELISA and immunohistochemistry were used for psoriasin and ELISA for IL-8. RESULTS: The mRNA expression of psoriasin was lower in patients before treatment compared with healthy controls (p = .05). After surgery, when the infection was cleared, psoriasin increased on mRNA (p = .04) and protein (p = .03) levels compared with before treatment. Immunostaining for psoriasin after treatment was prominent and localized in the cytoplasm of the epithelial cells. After treatment, IL-8 mRNA was reduced compared with before treatment (p = .05), but not on the protein level. No changes in mRNA expression of the other AMPs analyzed were observed in pretreatment and posttreatment samples. CONCLUSIONS: In this study of AMP expression in human papillomavirus-induced HSIL, we observed lower psoriasin levels before surgery compared with after treatment, when both mRNA and protein levels were similar to healthy controls. Interleukin 8, on the other hand, was increased before treatment, indicating an inflammatory response.

Psoriasin, a novel anti-Candida albicans adhesin.

Candida albicans belongs to the normal microbial flora on epithelial surfaces of humans. However, under certain, still not fully understood conditions, it can become pathogenic and cause a spectrum of diseases, from local infections to life-threatening septicemia. We investigated a panel of antimicrobial proteins and peptides (AMPs), potentially involved in mucosal immunity against this pathogen. Out of six studied AMPs, psoriasin was most up-regulated during a mucosal infection, an acute episode of recurrent Candida vulvovaginitis, although candidacidal activity has not been demonstrated. We here show that psoriasin binds to ß-glucan, a basic component of the C. albicans cell wall, and thereby inhibits adhesion of the pathogen to surfaces and increases IL-8 production by mucosal epithelial cells. In conclusion, we show a novel mechanism of action of psoriasin. By inhibiting C. albicans adhesion and by enhancing cytokine production, psoriasin contributes to the immune response against C. albicans. KEY MESSAGES: The antimicrobial peptide psoriasin is highly up-regulated during a local mucosal infection, Candida albicans vulvovaginitis. Psoriasin binds to ß-glucan in the Candida albicans cell wall and thereby inhibits adhesion of the pathogen. Binding of psoriasin to Candida albicans induces an immune response by mucosal epithelial cells.

Elevated nitric oxide in recurrent vulvovaginal candidiasis - association with clinical findings.

INTRODUCTION: Recurrent vulvovaginal candidiasis is defined as having three to four episodes per year and causes substantial suffering. Little is known about the mechanisms leading to relapses in otherwise healthy women. Nitric oxide is part of the nonspecific host defense and is increased during inflammation. Nitric oxide levels were measured and the expression of inducible nitric oxide synthase was analyzed in the vagina during an acute episode of recurrent vulvovaginal candidiasis and after treatment with fluconazole. MATERIAL AND METHODS: Twenty-eight women with symptoms of recurrent vulvovaginal candidiasis were enrolled together with 31 healthy controls. Nitric oxide was measured with an air-filled 25-mL silicon catheter balloon incubated in the vagina for five minutes and then analyzed by chemiluminescence technique. Vaginal biopsies were analyzed for the expression of inducible nitric oxide synthase. Symptoms and clinical findings were surveyed using a scoring system. The measurements and biopsies were repeated in patients after six weeks of fluconazole treatment. RESULTS: Nitric oxide levels were increased during acute infection (median 352 ppb) compared with controls (median 6 ppb), p < 0.0001. The levels decreased after treatment (median 18 ppb) but were still higher than in controls. Increased expression of inducible nitric oxide synthase was observed in the epithelial basal layer in patients before and after treatment compared with controls. Before treatment, there were positive correlations between nitric oxide and symptom (rs  = 0.644) and examination scores (rs  = 0.677), p < 0.001. CONCLUSIONS: Nitric oxide is significantly elevated in patients with recurrent vulvovaginal candidiasis during acute episodes of infection and decreases after antifungal treatment. The results illustrate the pronounced inflammatory response in recurrent vulvovaginal candidiasis correlating to symptoms of pain and discomfort.