Development of superficial bacterial and fungal infections models in Galleria mellonella for the study of antimicrobial photodynamic therapy

• Grant number: 21/13368-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2022
• End date: August 31, 2024
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Juliana Campos Junqueira
• Grantee: Éric Yukio Morissugui
• Host Institution: Instituto de Ciência e Tecnologia (ICT). Universidade Estadual Paulista (UNESP). Campus de São José dos Campos. São José dos Campos , SP, Brazil

Abstract

Cutaneous infections caused by Staphylococcus aureus, Acinetobacter baumannii, and Candida albicans represent a major challenge in the hospital environment due to the development of strains resistant to antibiotics and antifungals. Antimicrobial photodynamic therapy (aPDT) can be an alternative treatment for these infections; however, in vivo study models are restricted to vertebrate animals. Seeking to expand the number of in vivo studies and at the same time reduce the use of vertebrate animals in research, the objective of this proposal will be to establish burn models in Galleria mellonella that can be used for the study of aPDT in superficial infections caused by S. aureus, A. baumannii or C. albicans. For this, burn injuries will be induced in the dorsal region of the larvae, and then infected by suspensions of S. aureus, A. baumannii or C. albicans at different concentrations (105 to 109 cells/mL). After 30 min, larvae will be treated by aPDT using methylene blue as a photosensitizer and laser at 660 nm as a light source. The results will be evaluated using the survival curve and health index of larvae, in which movement activity, cocoon formation, and melanization will be evaluated. The data obtained from the survival curve and health index in G. mellonella will be analyzed, respectively, by the Kaplan-Meier method and analysis of variance followed by the Tukey test, considering a significance level of 5%.(AU)