Establishment and Evaluation of a <em>Candida albicans</em> Water-Soluble Extract-Induced Murine Model of Kawasaki Disease-Associated Coronary Arteritis

Kawasaki disease (KD) is a systemic vasculitis primarily affecting children, with coronary artery lesions being its most severe complication. In this study, an optimized mouse KD model was established using the water-soluble extract of Candida albicans (CAWS). Myocardial inflammation and related pathological changes were evaluated using HE staining and Masson trichrome staining. The immunofluorescence technique detected the infiltration of immune cells in cardiac tissue. The expression and localization of VDAC1 protein in myocardial tissue were detected by immunohistochemistry. In vitro, a phagocytic model was established by co-culturing RAW264.7 macrophages with Candida albicans spores, and the formation and function of autophagolysosomes were assessed using LC3 immunofluorescence staining and a Lyso-Tracker Red probe. Through dose screening, it was determined that 8 mg was the optimal modeling dose for inducing coronary artery inflammation, with a moderate mortality rate at this dose. HE staining showed that CAWS injection stably induced coronary artery lesions consistent with the characteristics of human Kawasaki disease in mice. Masson staining confirmed that there was significant collagen fiber deposition around the coronary arteries and aorta in the CAWS group of mice, which closely coincided with the inflammatory area, and a statistically significant difference was observed from the control group at 14 days (p < 0.001). Immunofluorescence revealed that, on the 14th day of modeling, the infiltration of multiple immune cells in the cardiac tissue of the CAWS group had significantly increased (p < 0.001). The immunohistochemical results showed that, on the 28th day of modeling, the expression of VDAC1 protein in the myocardial tissue of the CAWS group was significantly upregulated (p < 0.001). In vitro experiments have shown that in macrophages infected with Candida albicans spores, the formation of autophagolysosomes increases in the early stage, while autophagic flow is blocked in the later stage, suggesting a functional disorder.