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There is a rising global incidence of Candida strains with high levels of resistance to fluconazole and other antifungal drugs, hence the need for novel antifungal treatment strategies. Here, we describe the first evidence of antifungal activity of Q-Griffithsin (Q-GRFT), a recombinant oxidation-resistant variant of Griffithsin, a marine red algal lectin with broad-spectrum antiviral activity. We demonstrated that Q-GRFT binds to α-mannan in the Candida albicans cell wall. We also observed that Q-GRFT binding disrupted cell wall integrity and induced reactive oxidative species (ROS) formation, resulting in cell death. Furthermore, we showed that Q-GRFT inhibited the growth of other Candida species C. glabrata, C. parapsilosis, and C. krusei and had modest activity against some strains of multi- and pandrug-resistant C. auris. We found that Q-GRFT induced differential expression of numerous genes involved in response to cell stress, including those responsible for neutralizing ROS production and cell cycle regulation. In conclusion, this novel antifungal activity suggests that Q-GRFT is potentially an ideal drug candidate and represents an alternative strategy for the prevention and treatment of candidiasis. IMPORTANCE Fungal infections contribute to morbidity and mortality annually, and the number of organisms that are nonresponsive to the current available drug regimens are on the rise. There is a need to develop new agents to counter these infections and to add to the limited arsenal available to treat fungal infections. Our study has identified Q-GRFT, a broad-spectrum antiviral protein that harbors growth-inhibitory activity against several Candida strains, as a potential candidate for the prevention and treatment of fungal infections.

The effect of tenofovir and amphotericin coadministration on kidney function is poorly characterized. We measured creatinine during induction therapy and at 4 weeks after diagnosis in Ugandans undergoing cryptococcal meningitis therapy and classified as not receiving antiretroviral therapy (ART), receiving nontenofovir ART or receiving tenofovir-based ART. Longitudinal creatinine changes and grade 2-4 creatinine adverse events were evaluated across groups. Creatinine concentrations were similar across ART groups. At 4 weeks after diagnosis, creatinine was 0.25 mg/dL higher than at diagnosis, but similar across groups. Adverse event incidence was also similar across ART groups. Tenofovir and amphotericin coadministration did not increase the risk of kidney dysfunction.

Resistance to antifungal agents in vulvovaginal candidiasis has resulted in increasing morbidity among women globally. It is therefore crucial that new antimycotic agents are developed to counter this rising challenge. Q-Griffithsin (Q-GRFT) is a red algal lectin, manufactured in Nicotiana benthamiana. Griffithsin has well characterized broad spectrum antiviral activity and has demonstrated potent in vitro activity against multiple strains of Candida, including C. albicans. We have been working to incorporate Q-GRFT into topical microbicide products to prevent HIV-1 and HSV-2 transmission. The goal of this study was to evaluate the efficacy of a prototype Q-GRFT dosage form in prophylactic and therapeutic murine models of vaginal candidiasis, through microbiologic, histopathologic, and immune studies. In a preventive model, in comparison with infected controls, Q-GRFT treatment resulted in a lower fungal burden but did not alter the number of vaginal neutrophils and monocytes. In a therapeutic model, Q-GRFT enhanced fungal clearance when compared with infected untreated controls. Finally, histopathology demonstrated lower vaginal colonization with C. albicans following Q-GRFT treatment. Our results demonstrate that Q-GRFT has significant preventive and therapeutic activity in vaginal candidiasis offering additional benefit as a topical microbicide for prevention of HIV-1 and HSV-2 transmission. [ABSTRACT FROM AUTHOR]

Background In cryptococcal meningitis phase 2 clinical trials, early fungicidal activity (EFA) of Cryptococcus clearance from cerebrospinal fluid (CSF) is used as a surrogate endpoint for all-cause mortality. The Food and Drug Administration allows for using surrogate endpoints for accelerated regulatory approval, but EFA as a surrogate endpoint requires further validation. We examined the relationship between rate of CSF Cryptococcus clearance (EFA) and mortality through 18 weeks. Methods We pooled individual-level CSF data from 3 sequential cryptococcal meningitis clinical trials conducted during 2010–2017. All 738 subjects received amphotericin + fluconazole induction therapy and had serial quantitative CSF cultures. The log10-transformed colony-forming units (CFUs) per mL CSF were analyzed by general linear regression versus day of culture over the first 10 days. Results Mortality through 18 weeks was 37% for EFA > = 0.60 (n = 170), 36% for 0.40–0.59 (n = 182), 39% for 0.30–0.39 (n = 112), 35% for 0.20–0.29 (n = 87), and 50% for those with EFA < 0.20 CFU/mL/day (n = 187). The hazard ratio for 18-week mortality, comparing those with EFA < 0.20 to those with EFA > = 0.20, was 1.60 (95% confidence interval, 1.25, 2.04; P  = .002). The lowest EFA group had lower median CD4 T-cell counts (P  < .01) and lower proportion of patients with CSF pleocytosis (P  < .001). Conclusions EFA is associated with all-cause mortality in cryptococcal meningitis. An EFA threshold of > = 0.20 log10 CFU/mL/day was associated with similar 18-week mortality (37%) compared to 50% mortality with EFA < 0.20. This EFA threshold may be considered a target for a surrogate endpoint. This builds upon existing studies to validate EFA as a surrogate endpoint. [ABSTRACT FROM AUTHOR]

Altered mental status in cryptococcal meningitis results in poorer survival, but underlying causes of altered mentation are poorly understood. Within two clinical trials, we assessed risk factors for altered mental status (GCS score<15) considering baseline clinical characteristics, CSF cytokines/chemokines, and antiretroviral therapy. Among 326 enrolled participants, 97 (30%) had GCS<15 and these patients had lower median CSF cryptococcal antigen titers (P = .042) and CCL2 (P = .005) but higher opening pressures (320 vs. 269 mm H2O; P = .016), IL-10 (P = .044), and CCL3 (P = .008) compared with persons with GCS=15. Altered mental status may be associated with host immune response rather than Cryptococcus burden. [ABSTRACT FROM AUTHOR]