Hematopoietic Stem Cell Dysfunction in the Elderly After Severe Injury: Chronic Stress and Anemia Recovery Following Major Trauma

Summary

Traumatic injury is a leading cause of morbidity and mortality in young adults, and remains a substantial economic and health care burden. Despite decades of promising preclinical and clinical investigations in trauma, investigators understanding of these entities is still incomplete, and few therapies have shown success. During severe trauma, bone marrow granulocyte stores are rapidly released into the peripheral circulation. This release subsequently induces the expansion and repopulation of empty or evacuated space by hematopoietic stem cells (HSCs). Although the patient experiences an early loss of bone marrow myeloid-derived cells, stem cell expansion is largely skewed towards the repopulation of the myeloid lineage/compartment. The hypothesis is that this 'emergency myelopoiesis' is critical for the survival of the severely traumatized and further, failure of the emergency myelopoietic response is associated with global immunosuppression and susceptibility to secondary infection. Also, identifying the release of myeloid derived suppressor cells (MDSCs) in the circulation of human severe trauma subjects. This process is driven by HSCs in the bone marrow of trauma subjects. Additionally, MDSCs may have a profound effect on the nutritional status of the host. The appearance of these MDSCs after trauma is associated with a loss of muscle tissue in these subjects. This muscle loss and possible increased catabolism have huge effects on long term outcomes for these subjects. It is the investigator's goal to understand the differences that occur in these in HSCs and muscle cells as opposed to non-injured and non-infected controls. This work will lead to a better understanding of the myelopoietic and catabolic response following trauma.

Description

Eligibility

Age range

18+ years

Sex

All

Healthy volunteers

No

Interventions

• Other
  Bone marrow collection

  Bone marrow will be collected from the patient at time of orthopedic repair in the operating room. A second sample may be collected if the patient is required to return to the operating room for further repair of orthopedic injury.

• Other
  Blood collection

  Blood sample collection will be collected from the patient at time of orthopedic repair in the operating room. A second sample may be collected if the patient is required to return to the operating room for further repair of orthopedic injury.

• Other
  Clinical data collection

  Clinical data collection will encompass demographic information, past and present medical records, laboratory, microbiology, and all other test results, x-ray, CT, MRI, US and all other imaging test results, records about any medication received during admission, records of physical exam during admission, records of all vital signs and hemodynamic monitoring during admission, records of any procedure or intervention during admission, records of any procedure or intervention during hospital admission, condition at the discharge and discharge facility.

Location