Galleria mellonella as non-vertebrate host infection model for the study of Porphyromonas gingivalis: analysis of virulence and sensitivity to photodynamic therapy

Abstract

The objective of this study will be to develop an in vivo model in Galleria mellonella for the study of Porphyromonas gingivalis, a strict anaerobic bacterium important for research in dentistry. A model for the study of P. gingivalis virulence and antimicrobial therapies tests will be developed, such as photodynamic therapy. To study the virulence different P. gingivalis concentrations will be inoculated into G. mellonella and the development of experimental infection will be evaluated by survival curve and hemocytes count, which are the immune cells present in the hemolymph of these animals. For the evaluation of G. mellonella as photodynamic therapy study model, toxicity tests will be performed with different concentrations of the methylene blue photosensitizer, as well as tests to determine the optimal parameters light irradiation (AsGaAl laser 660 nm). The following groups of G. mellonella larvae infected with P. gingivalis will be evaluated to four experimental conditions: inoculation of the photosensitizer and application of Laser (P+ L+), Physiologic solution inoculation and application of Laser (P-L +), inoculation the Photosensitizer without Laser (P+ L-) and inoculation of physiologic solution without Laser (P- L). The effects of PDT on infection by P. gingivalis will be evaluated by survival curve analysis of the larvae. The data obtained in G. mellonella survival curve will be analyzed by Log-rank method and hemocytes count by ANOVA test, considering a significance level of 5%.