Pneumonia treatment by photodynamic therapy with extracorporeal illumination - an experimental model. uri icon

abstract

  • Infectious pneumonia is a major cause of morbidity/mortality, mainly because of the increasing rate of microorganisms resistant to antibiotics. Photodynamic Therapy (PDT) is emerging as a promising approach, as effects are based on oxidative stress, preventing microorganism resistance. In two previous studies, the invitro inactivation of Streptococcus pneumoniae using indocyanine green (ICG) and infrared light source was a success killing 5 log10 colony-forming units (CFU/mL) with only 10mol/L ICG. In this work, a proof-of-principle protocol was designed to treat lung infections by PDT using extracorporeal illumination with a 780nm laser device and also ICG as photosensitizer. Hairless mice were infected with S. pneumoniae and PDT was performed two days after infection. For control groups, CFU recovery ranged between 103-104/mouse. For PDT group, however, no bacteria were recovered in 80% of the animals. Based on this result, animal survival was evaluated separately over 50days. No deaths occurred in PDT group, whereas 60% of the control group died. Our results indicate that extracorporeal PDT has the potential for pneumonia treatment, and pulmonary decontamination with PDT may be used as a single therapy or as an antibiotics adjuvant.

published proceedings

  • Physiol Rep

author list (cited authors)

  • Geralde, M. C., Leite, I. S., Inada, N. M., Salina, A., Medeiros, A. I., Kuebler, W. M., Kurachi, C., & Bagnato, V. S.

complete list of authors

  • Geralde, Mariana C||Leite, Ilaiáli S||Inada, Natalia M||Salina, Ana Carolina G||Medeiros, Alexandra I||Kuebler, Wolfgang M||Kurachi, Cristina||Bagnato, Vanderlei S

publication date

  • March 2017

publisher