Hematopoietic Stem Cell Dysfunction in the Elderly After Severe Injury

This is a prospective study to understand how trauma injuries changes the hematopoeitic stem cells (HSCs) in the bone marrow and muscle cells after trauma injury in elderly subjects is different when compared to non-injured subjects. There will be three groups for this study: 1) Elective hip surgery subjects, 2) Trauma subjects and 3) deidentified bone marrow of healthy controls. Samples of bone marrow and a blood sample will be collected at the time of surgery. The deidentified bone marrow of healthy controls will come from a tissue bank. The blood will be used to perform PB colony assays, ELISAs to test for the following parameters: EPO, G-CSF, Reticulocyte, iron levels and cytokines and inflammatory markers. The bone marrow and blood samples will be processed and sorted to isolate hematopoeitic stem cells for genomic content to determine genomic expression, oxidative stress, mitochondrial activity, apoptosis, autophagy, analysis of circulating erythroid progenitor cells, reticulocytes, granulocyte-colony stimulating factor assays, erythropoietin and iron levels. Clinical data and hemodynamic measurements will be collected daily while subjects are hospitalized and trauma surgery subjects will be followed to evaluate for malunion and subsequent additional surgical procedures for repair.