A preliminary study on the virulence of Aspergillus lentulus isolated from a patient with COPD on the Galleria mellonella model

Abstract

Abstract: Objective Establish an animal model of Aspergillus lentulus (A. lentulus or A.L) infection, and use the animal model to explore the virulence of A. lentulus. Methods One hundred and twenty-five Galleria mellonella were randomly divided into five groups, with Aspergillus lentulus clinical strain and Aspergillus lentulus standard strain as the experimental group, Aspergillus fumigatus and Candida albicans as the control group, and PBS as the blank control group. The experimental group and the control group were made into 10⁶ CFU/mL spore suspension, respectively, and infected with each group of Galleria mellonella. The survival of Galleria mellonella within 72 hours was recorded and the survival curve was made. The intestinal tissues of Galleria mellonella were extracted 24 hours later. The intestinal tissue damage was observed by HE staining. The fungal load in the intestinal tract of the Galleria mellonella and the positive rate of fungal reverse culture were determined by tissue homogenization. The fungal morphology of the intestinal culture was observed by fungal fluorescence staining. Results There was a statistical difference between the survival numbers of Galleria mellonellas of A. lentulus clinical strain and A. lentulus standard strain and A. fumigatus group and C. albicans group (P<0.05); The results showed that the intestinal wall structure of the clinical strain of A. lentulus and the standard strain of A. lentulus was roughly normal, with a small amount of hyphae, spores and inflammatory cell infiltration in local edema. The intestinal structure of the control group was seriously damaged, with hyphae, spores and a large number of inflammatory cell infiltrations; There was a statistical difference in the intestinal fungal load and the positive rate of fungal reverse culture in each group of different fungal species infected Galleria mellonellas (P<0.05); According to the fluorescence microscope observation of the fungus, the clinical strain and standard strain of A. lentulus had more hyphae and fewer spores, while the C. albicans, and A. fumigatus group had more spores. Conclusion Compared with A.fumigatus and C. albicans, the A. lentulus strain has weaker virulence and intestinal damage to larvaes and has a lower lethality rate.

Key words: A. lentulus, Galleria mellonella, A. fumigatus, C. albicans, virulence

CLC Number:

R379.6

XIE Yun, ZHANG Lijuan, PALIDAE·Abliz. A preliminary study on the virulence of Aspergillus lentulus isolated from a patient with COPD on the Galleria mellonella model[J]. Chinese Journal of Mycology, 2021, 16(3): 155-160.

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