Antimicrobial Effect of Reactive Iodine Species Produced by Photodynamic Therapy Against Streptococcuspneumoniae in a Lung Alveolar Transwell Model

Author(s)

Jasinevicius, Gabriel Oliveira ; Guimaraes, Francisco Eduardo Gontijo ; Kurachi, Cristina

• Document type: Journal article
• Source: 2024 SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE, SBFOTON IOPC 2024; v. N/A, p. 3-pg., 2024-01-01.

Abstract

Antimicrobial photodynamic therapy (aPDT) effectiveness against pathogenic microorganisms can be enhanced by potassium iodide (KI). KI achieves this by forming longer-lived reactive iodine species (RIS), compared to the reactive oxygen species (ROS) in conventional PDT. This study investigated the synergistic effects of KI and Methylene Blue (MB) in aPDT against Streptococcus pneumoniae within a lung alveolar transwell model. Results showed that KI significantly enhanced MB-mediated aPDT, increasing efficacy against S. pneumoniae colony-forming units (CFUs). Notably, the photoproducts (RIS) alone reduced S. pneumoniae CFUs by over 3 logs without harming mammalian cells. This highlights the potential of KI-enhanced aPDT. (AU)

• FAPESP's process: 09/54035-4 - Facility for advanced studies of biosystems and nanostructured materials
• Grantee: Igor Polikarpov
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 13/07276-1 - CEPOF - Optics and Photonic Research Center
• Grantee: Vanderlei Salvador Bagnato
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 14/50857-8 - National Institute in Basic Optics and Applied to Life Sciences
• Grantee: Vanderlei Salvador Bagnato
• Support Opportunities: Research Projects - Thematic Grants