Autografts containing bone marrow (BM) are current gold standard in the treatment of critical size bone defects, delayed union and bone nonunion defects. Although reaching unprecedented healing rates in bone reconstruction, the mode of action and cell-cell interactions of bone marrow mononuclear cell (BM-MNC) populations have not yet been described. BM-MNCs consist of a heterogeneous mixture of hematopoetic and non-hematopoetic lineage fractions. Cell culture in a 3D environment is necessary to reflect on the complex mix of these adherend and non-adherend cells in a physiologically relevant context. Therefore, the main aim of this approach was to establish conditions for a stable 3D BM-MNC culture to assess cellular responses on fracture healing strategies. BM samples were obtained from residual material after surgery with positive ethical vote and informed consent of the patients. BM-MNCs were isolated by density gradient centrifugation, and cellular composition was determined by flow cytometry to obtain unbiased data sets on contained cell populations. Collagen from rat tail and human fibrin was used to facilitate a 3D culture environment for the BM-MNCs over a period of three days. Effects on cellular composition that could improve the regenerative potential of BM-MNCs within the BM autograft were assessed using flow cytometry. Cell-cell-interactions were visualized using confocal microscopy over a period of 24 hours. Cell localization and interaction partners were characterized using immunofluorescence labeled paraffin sectioning. Main BM-MNC populations like Monocytes, Macrophages, T cells and endothelial progenitor cells were determined and could be conserved in 3D culture over a period of three days. The 3D cultures will be further treated with already clinically available reagents that lead to effects even within a short-term exposure to stimulate angiogenic, osteogenic or immunomodulatory properties. These measures will help to ease the translation from “bench to bedside” into an intraoperative protocol in the end.
Hypovitaminosis D has been identified as a common
risk factor for fragility fractures and poor fracture healing. Epidemiological
data on vitamin D deficiency have been gathered in various populations,
but the association between vertebral fragility fractures and hypovitaminosis
D, especially in males, remains unclear. The purpose of this study
was to evaluate serum levels of 25-hydroxyvitamin D (25-OH D) in
patients presenting with vertebral fragility fractures and to determine
whether patients with a vertebral fracture were at greater risk
of hypovitaminosis D than a control population. Furthermore, we
studied the seasonal variations in the serum vitamin D levels of
tested patients in order to clarify the relationship between other
known risk factors for osteoporosis and vitamin D levels. We measured
the serum 25-OH D levels of 246 patients admitted with vertebral
fractures (105 men, 141 female, mean age 69 years, Cite this article:
