E. S. Miller1, T. J. Loftus1, K. B. Kannan1, P. A. Efron1, A. M. Mohr1 1University Of Florida College Of Medicine,Department Of Surgery,Gainesville, FL, USA
Introduction: Severe traumatic injury induces a prolonged hypercatecholamine state which is associated with suppression of bone marrow erythroid progenitor colony growth that is mediated by the bone marrow stroma. This study sought to determine the effects of severe trauma on stromal hematopoietic cytokine expression. Utilizing human bone marrow stromal cells (HS-5 cells) cultured with plasma from healthy patients and trauma patients at a Level 1 trauma center, we hypothesized that trauma plasma would increase stromal expression of interleukin-6 (IL-6), granulocyte colony stimulating factor (G-CSF), erythropoietin (EPO), stem cell factor (SCF), and nuclear factor kappa-light-chain-enhancer of activated B cells (Nf-kB).
Methods: HS-5 cells were cultured with the plasma of both healthy volunteers and trauma patients. At 6, 24, and 48 hours the expression of interleukin 6 (IL-6), granulocyte colony stimulating factor (G-CSF), erythropoietin (EPO), stem cell factor (SCF) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) were measured using quantitative polymerase chain reaction. Statistical results were performed using GraphPad Prism. All data were presented as fold change mean±SD. Data significance was defined as *p<0.05 by t-test.
Results: IL-6 expression was increased at each time point with trauma plasma and IL-6 was significantly elevated when compared to normal plasma at 24 and 48 hours (Table). G-CSF and EPO expression were increased at all time points with trauma plasma and there was significant increase at 48 hours compared to normal plasma. Trauma plasma did not alter SCF expression at any time point. NF-κB expression increased from 6 hours to 24 and 48 hours with trauma plasma group. The addition of normal plasma and trauma plasma to HS-5 cells resulted in 89-100% cell viability.
Conclusion: Circulating plasma from trauma patients activated bone marrow stroma when compared to normal plasma. The addition of trauma plasma to human bone marrow stromal cells upregulated IL-6, G-CSF and EPO expression after 48 hours but did not affect SCF or NF-κB expression. This study demonstrates that there is systemic regulation of bone marrow stroma following severe trauma.
