Efficacy and safety of antifungal decontamination of preservation fluid under static cold storage conditions: an in vitro study

Objective To evaluate the antifungal efficacy and safety of amphotericin B (AmB), liposomal amphotericin B (L-AmB), and voriconazole (VOR) against common fungal contaminants in preservation fluid (PF) under simulated static cold storage (SCS) conditions, providing in vitro evidence to future graft decontamination strategies. Methods Fungal suspensions of Candida albicans (C. albicans) , Aspergillus fumigatus (A. fumigatus) , and Mucor hiemalis ( M. hiemalis ) in PF were incubated at 0–4 °C for 3 h with AmB (5, 15, and 25 mg/L), L-AmB (50, 100, and 200 mg/L), or VOR (50, 100, and 200 mg/L). Colony-forming units and average inhibition rates (AIRs) were determined. Cytotoxicity was assessed in human renal proximal tubular epithelial (HK-2) cells exposed to the highest concentration of each agent at 0–4 °C for 3, 6, and 18 h. Results No viable colonies were detected for VOR against C. albicans at all concentrations. Against A. fumigatus , L-AmB achieved AIRs of 48.13%–86.14%, exceeding AmB (8.24%–23.22%; P = 0.033) and no statistically significant difference was observed between L-AmB and VOR (15.36%–62.55%; P = 0.267). Against M. hiemalis , medium- and high-dose L-AmB achieved AIRs of 64.93%–88.81%, exceeding AmB (25.37%–36.57%; P = 0.001) and VOR (0%–9.70%; P < 0.001). AmB caused marked time-dependent cytotoxicity, whereas L-AmB and VOR did not significantly reduce HK-2 cell viability under the tested conditions. Conclusions During 3 h SCS, L-AmB effectively decontaminated A. fumigatus and M. hiemalis with acceptable cytocompatibility, while no viable C. albicans colonies were detected following VOR treatment. Conventional AmB may be unsuitable for ex vivo graft decontamination because of its cytotoxicity.