| Autor: |
Brandenburg KS; Dental and Craniofacial Trauma Research and Tissue Regeneration Directorate (DCTRTRD), U.S. Army Institute of Surgical Research (USAISR), JBSA-Fort Sam Houston, San Antonio, Texas., Weaver AJ Jr; Dental and Craniofacial Trauma Research and Tissue Regeneration Directorate (DCTRTRD), U.S. Army Institute of Surgical Research (USAISR), JBSA-Fort Sam Houston, San Antonio, Texas., Qian L; Dental and Craniofacial Trauma Research and Tissue Regeneration Directorate (DCTRTRD), U.S. Army Institute of Surgical Research (USAISR), JBSA-Fort Sam Houston, San Antonio, Texas., You T; Dental and Craniofacial Trauma Research and Tissue Regeneration Directorate (DCTRTRD), U.S. Army Institute of Surgical Research (USAISR), JBSA-Fort Sam Houston, San Antonio, Texas., Chen P; Dental and Craniofacial Trauma Research and Tissue Regeneration Directorate (DCTRTRD), U.S. Army Institute of Surgical Research (USAISR), JBSA-Fort Sam Houston, San Antonio, Texas., Karna SLR; Dental and Craniofacial Trauma Research and Tissue Regeneration Directorate (DCTRTRD), U.S. Army Institute of Surgical Research (USAISR), JBSA-Fort Sam Houston, San Antonio, Texas., Fourcaudot AB; Dental and Craniofacial Trauma Research and Tissue Regeneration Directorate (DCTRTRD), U.S. Army Institute of Surgical Research (USAISR), JBSA-Fort Sam Houston, San Antonio, Texas., Sebastian EA; Dental and Craniofacial Trauma Research and Tissue Regeneration Directorate (DCTRTRD), U.S. Army Institute of Surgical Research (USAISR), JBSA-Fort Sam Houston, San Antonio, Texas., Abercrombie JJ; Dental and Craniofacial Trauma Research and Tissue Regeneration Directorate (DCTRTRD), U.S. Army Institute of Surgical Research (USAISR), JBSA-Fort Sam Houston, San Antonio, Texas., Pineda U; Dental and Craniofacial Trauma Research and Tissue Regeneration Directorate (DCTRTRD), U.S. Army Institute of Surgical Research (USAISR), JBSA-Fort Sam Houston, San Antonio, Texas., Hong J; Dental and Craniofacial Trauma Research and Tissue Regeneration Directorate (DCTRTRD), U.S. Army Institute of Surgical Research (USAISR), JBSA-Fort Sam Houston, San Antonio, Texas.; Armed Forces Busan Hospital, Republic of Korea Army., Wienandt NA; Research Support Division, USAISR., Leung KP; Dental and Craniofacial Trauma Research and Tissue Regeneration Directorate (DCTRTRD), U.S. Army Institute of Surgical Research (USAISR), JBSA-Fort Sam Houston, San Antonio, Texas. |
| Abstrakt: |
We used a modified Walker-Mason scald burn rat model to demonstrate that Pseudomonas aeruginosa, a common opportunistic pathogen in the burn ward and notable biofilm former, establishes biofilms within deep partial-thickness burn wounds in rats.Deep partial-thickness burn wounds, ~10% of the TBSA, were created in anesthetized male Sprague-Dawley rats (350-450 g; n = 84). Immediately post-burn, 100 µl of P. aeruginosa in phosphate-buffered saline at 1 × 103, 1 × 104, or 1 × 105 cells/wound was spread over the burn surface . At 1, 3, 7, and 11 days post-burn, animals were euthanized and blood and tissue were collected for complete blood counts, colony-forming unit (CFU) counts, biofilm gene expression, histology, scanning electron microscopy (SEM), and myeloperoxidase activity in the burn eschar.P. aeruginosa developed robust biofilm wound infections, plateauing at ~1 × 109 CFU/g burn tissue within 7 days regardless of inoculum size. Expression of Pseudomonas alginate genes and other virulence factors in the infected wound indicated formation of mature P. aeruginosa biofilm within the burn eschar. Compared to un-inoculated wounds, P. aeruginosa infection caused both local and systemic immune responses demonstrated by changes in systemic neutrophil counts, histology, and myeloperoxidase activity within the burn wound. Additionally, SEM showed P. aeruginosa enmeshed within an extracellular matrix on the burn surface as well as penetrating 500-600 µm deep into the eschar.P. aeruginosa establishes biofilms within deep partial-thickness burn wounds and invades deep into the burned tissue. This new in vivo biofilm infection model is valuable for testing novel anti-biofilm agents to advance burn care. |
