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Transfusion-Associated Microchimerism in Previously Injured Individuals Who Received a Blood Transfusion

This study has been terminated.
(A separate study (similar subjects) identified transfusion-associated microchimerism only rarely, making this observational study impractical to conduct.)
Information provided by (Responsible Party):
National Heart, Lung, and Blood Institute (NHLBI) Identifier:
First received: February 28, 2007
Last updated: July 11, 2016
Last verified: October 2014
Blood transfusions are frequently necessary in situations in which there is a large amount of blood loss. In some individuals who receive a blood transfusion, white blood cells from the donor's blood may remain in the body for years, a condition known as microchimerism. This study will evaluate the occurrence of microchimerism among the following three groups of individuals who previously received transfusions: 1) individuals with traumatic injuries; 2) individuals with burn injuries; and 3) individuals who underwent elective orthopedic operations.

Blood Transfusion
Wounds and Injuries

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Retrospective
Official Title: Retrospective Study of the Prevalence of Transfusion-Associated Microchimerism Following Traumatic Injury, Burns, and Elective Orthopedic Procedures

Resource links provided by NLM:

Further study details as provided by National Heart, Lung, and Blood Institute (NHLBI):

Primary Outcome Measures:
  • Microchimerism [ Time Frame: 5-11 years after transfusion ]

Biospecimen Retention:   Samples With DNA
Whole blood, plasma, peripheral blood mononuclear cells

Enrollment: 59
Study Start Date: August 2008
Study Completion Date: October 2011
Primary Completion Date: October 2011 (Final data collection date for primary outcome measure)
Traumatic injury
Elective orthopedic surgery
Burn injury

Detailed Description:

Approximately 10% to 15% of injured patients who receive blood transfusions experience a condition known as transfusion-associated microchimerism. This occurs when white blood cells, or leukocytes, from the donor's blood persist in the recipient long after the transfusion occurs. The genetically distinct donor cells can remain in the individual for decades, and may account for as many as 4% of the white blood cells in the recipient's body. This suggests that the donor cells are tolerated by the recipient's immune system. The purpose of this study is to compare the incidence of microchimerism among individuals with three different types of injuries: 1) traumatic injuries; 2) thermal, or burn, injuries; and 3) injuries resulting from elective orthopedic surgical procedures.

In this study, blood samples will be collected from individuals who were treated for traumatic injury, thermal injury, or elective orthopedic surgical procedures at the University of California at Davis Medical Center. Individuals who were treated from 2000 to 2003 and received a blood transfusion, as well as a control group of individuals who did not receive a transfusion, will be approached to enroll in the study. Individuals who agree to participate will have their blood analyzed for evidence of microchimerism. Information on health status, injury characteristics, hospital care, blood transfusion details, and blood donor characteristics will be collected from all participants.


Ages Eligible for Study:   8 Years and older   (Child, Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Probability Sample
Study Population
Previously hospitalized patients

Inclusion Criteria:

  • Hospitalized for traumatic injury, thermal injury, or an elective orthopedic surgical procedure from 2000 to 2003 at the University of California at Davis Medical Center
  • Received at least 1 unit of transfused red blood cells

Exclusion Criteria:

  • Currently incarcerated
  • Inadequate decision-making capacity of the participant and no available surrogate decision-maker
  • Prior bone marrow or solid organ transplantation
  • Prior blood transfusion other than at the time of hospitalization
  • Any history of an autoimmune disorder prior to hospitalization
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Please refer to this study by its identifier: NCT00441779

United States, California
University of California, Davis, Medical Center
Sacramento, California, United States, 95817
Sponsors and Collaborators
National Heart, Lung, and Blood Institute (NHLBI)
Principal Investigator: Michael P. Busch, MD, PhD Blood Systems Research Institute