Biology subjects

Kuriu, A.

Publications and source records attributed to Kuriu, A..

2 recordsLinked to original sources

bioRxiv2026

A Xenopus laevis Model for Systemic Fungal Infections

Xenopus laevis possesses both innate and adaptive immune systems, and we previously demonstrated its utility as an infection model for human bacterial pathogens. In this study, we investigated the utility of X. laevis as a model for fungal infections. The human-pathogenic fungi Candida albicans and Aspergillus fumigatus exhibited greater lethality in X. laevis than the nonpathogenic fungi Saccharomyces cerevisiae and Schizosaccharomyces pombe. In frogs infected with C. albicans, viable fungal cells were detected in the blood and multiple organs early after infection, and gross white lesions and fungal hyphae were observed in the kidneys. C. albicans infection also increased renal expression of the proinflammatory cytokine gene s tnf and il1b, as well as the tissue injury-associated gene clu. Treatment with the antifungal agents amphotericin B and micafungin significantly improved the survival of C. albicans-infected frogs. Furthermore, a homozygous deletion mutant of UME6, a gene associated with C. albicans virulence, exhibited reduced lethality compared with the wild-type strain. These findings establish X. laevis as a vertebrate model of systemic fungal infection that enables the evaluation of fungal virulence, host responses, and the therapeutic efficacy of antifungal agents.

microbiology↗

bioRxiv2025

Xenopus laevis as an infection model for human pathogenic bacteria

Animal infection models are essential for understanding bacterial pathogenicity and corresponding host immune responses. In this study, we investigated whether juvenile Xenopus laevis could be used as an infection model for human pathogenic bacteria. Xenopus frogs succumbed to intraperitoneal injection containing the human pathogenic bacteria Staphylococcus aureus, Pseudomonas aeruginosa, and Listeria monocytogenes. In contrast, non-pathogenic bacteria Bacillus subtilis and Escherichia coli did not induce mortality in Xenopus frogs. The administration of appropriate antibiotics suppressed mortality caused by S. aureus and P. aeruginosa. Strains lacking the agr locus, cvfA (rny) gene, or hemolysin genes in S. aureus, LIPI-1-deleted mutant of L. monocytogenes, which attenuate virulence within mammals, exhibited reduced virulence in Xenopus frogs compared to their respective wild-type counterparts. Bacterial distribution analysis revealed that S. aureus persisted the blood, liver, heart, and muscles of Xenopus frogs until death. These results suggested that intraperitoneal injection of human pathogenic bacteria induces sepsis-like symptoms in Xenopus frogs supporting their use as a valuable animal model for evaluating antimicrobial efficacy and identifying virulence genes in various human pathogenic bacteria.

microbiology↗