TY - JOUR

T1 - Inflammatory proteins in infected bone tissue – An explorative porcine study

AU - Bue, Mats

AU - Bergholt, Natasja Leth

AU - Jensen, Louise Kruse

AU - Jensen, Henrik Elvang

AU - Søballe, Kjeld

AU - Stilling, Maiken

AU - Hanberg, Pelle

PY - 2020

Y1 - 2020

N2 - Objective: To explore the in situ inflammatory proteins in the local extracellular fluid of infected bone tissue. Material and methods: Seven pigs went through a two-step surgery performing a traumatically implant-associated Staphylococcus aureus osteomyelitis in the proximal tibia. Five days later, microdialysis catheters (membrane cut off: 20 kDa) were placed in the implant cavity, infected and healthy cancellous bone, and infected and healthy subcutaneous tissue. Plasma samples were collected simultaneously. We employed an antibody-based proximity extension assay (Olink Inflammatory panel) for the measurement of inflammatory molecules within plasma and extracellular fluid of the investigated tissue compartments. Results: A higher normalized protein expression in the infected bone tissue in comparison to healthy bone tissue was identified for proteins associated with angiogenesis and bone remodeling: OPG, TGFα, MCP-1, VEGFA, and uPA. Moreover, a parallel detectability of the systemic range of cytokines and chemokines as from the investigated local tissue compartments was demonstrated, indicating the same occurrence of proteins in the local environment as within plasma. Conclusion: An angiogenic and osteogenic inflammatory protein composition within the extracellular fluid of infected bone tissue was described. The findings support the current histopathological knowledge and, therefore, microdialysis may represent a valid method for sampling of material for protein investigation of the in vivo inflammatory composition within the extracellular environment in infected bone tissue.

AB - Objective: To explore the in situ inflammatory proteins in the local extracellular fluid of infected bone tissue. Material and methods: Seven pigs went through a two-step surgery performing a traumatically implant-associated Staphylococcus aureus osteomyelitis in the proximal tibia. Five days later, microdialysis catheters (membrane cut off: 20 kDa) were placed in the implant cavity, infected and healthy cancellous bone, and infected and healthy subcutaneous tissue. Plasma samples were collected simultaneously. We employed an antibody-based proximity extension assay (Olink Inflammatory panel) for the measurement of inflammatory molecules within plasma and extracellular fluid of the investigated tissue compartments. Results: A higher normalized protein expression in the infected bone tissue in comparison to healthy bone tissue was identified for proteins associated with angiogenesis and bone remodeling: OPG, TGFα, MCP-1, VEGFA, and uPA. Moreover, a parallel detectability of the systemic range of cytokines and chemokines as from the investigated local tissue compartments was demonstrated, indicating the same occurrence of proteins in the local environment as within plasma. Conclusion: An angiogenic and osteogenic inflammatory protein composition within the extracellular fluid of infected bone tissue was described. The findings support the current histopathological knowledge and, therefore, microdialysis may represent a valid method for sampling of material for protein investigation of the in vivo inflammatory composition within the extracellular environment in infected bone tissue.

KW - Fluid space of bone

KW - Inflammatory proteins in infected bone tissue

KW - Microdialysis

KW - Osteomyelitis porcine model

KW - Proximity extension assay

U2 - 10.1016/j.bonr.2020.100292

DO - 10.1016/j.bonr.2020.100292

M3 - Journal article

C2 - 32637468

AN - SCOPUS:85087032862

VL - 13

JO - Bone Reports

JF - Bone Reports

SN - 2352-1872

M1 - 100292

ER -