Abstract
Background: Severe trauma disrupts bone marrow function resulting in persistent anemia and immunosuppression. Exosomes are extracellular vesicles implicated in disease, cellular functions, and immunomodulation. The effects of trauma plasma-derived exosomes on bone marrow hematopoiesis are unstudied; we hypothesized that trauma plasma-derived exosomes suppress bone marrow hematopoietic progenitor cell (HPC) growth and contribute to increased inflammatory cytokines and HPC mobilization. Methods: Plasma was collected from a prospective, cohort study of trauma patients (n = 15) with hip and/or femur fractures and an ISS > 15 and elective total hip arthroplasty (THA) patients (n = 15). Exosomes were isolated from both groups using the Invitrogen Total Exosome Isolation Kit. Healthy bone marrow was cultured with 2% plasma, 50 μg, 100 μg, or 200 μg of exosomal protein and HPC (granulocyte, erythrocyte, monocyte, megakaryocyte colony-forming units [CFU-GEMM], erythroid burst-forming units [BFU-E], and macrophage colony-forming units [CFU-GM]) growth assessed. After culturing healthy bone marrow stroma with 100 μg of exosomal protein, expression of cytokines and factors influencing HPC mobilization were assessed by qPCR. Differences were compared using the ANOVA, with significance defined as P < 0.05. Results: The only demographic difference was age; trauma patients were significantly younger than THA (mean 44 vs. 63 years). In vitro exposure to trauma plasma significantly decreased growth of all HPCs. In vitro exposure to 100 μg or 200 μg of trauma exosomal protein significantly decreased growth of BFU-E and CFU-GM, whereas 50 μg had no effect. Culture of trauma exosomal protein with bone marrow stromal cells resulted in increased expression of IFN-γ, IL-1α, TNF-α, G-CSF, CXCR4, SDF-1, and VCAM-1 in bone marrow stroma. Conclusions: Both plasma and plasma-derived exosomes from trauma patients adversely affect bone marrow function. Plasma-derived exosomes may contribute to altered hematopoiesis after severe trauma; analysis of exosomal content may improve our understanding of altered bone marrow function.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.