Transfusion-Associated Microchimerism in Individuals Receiving a Blood Transfusion After a Traumatic Injury

Study Overview
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Brief Summary
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Individuals who experience a traumatic injury often have a significant amount of blood loss and may require a blood transfusion. 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 examine the reasons why microchimerism occurs in some blood transfusion recipients and not others.

Detailed Description
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Approximately 20% of individuals who suffer a traumatic injury require a blood transfusion; of these, 10% to 15% 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 examine the specific factors that predispose some blood transfusion recipients to develop microchimerism. In this study, blood samples will be collected from injured individuals who arrive at the University of California at Davis Medical Center. Individuals who receive a blood transfusion, as well as a control group of individuals who do not receive a transfusion, will be approached to enroll in the study. Individuals who agree to participate will have their blood collected at Days 7, 14, and 28 and Months 3 and 6. Study researchers will analyze the blood for evidence of microchimerism. Participants with microchimerism will undergo additional blood collection at Months 12, 18, 24, 30, and 36. Information will be collected from all participants on health status, injury characteristics, hospital care, blood transfusion details, and blood donor characteristics.

Official Title
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Prospective Study of the Kinetics and Mechanisms of Transfusion-associated Microchimerism in Injured Patients

Conditions
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Chimerism, Blood Transfusion, Wounds and Injuries

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Hospitalized for a traumatic injury Received at least one 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

Ages Eligible for Study
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Minimum Age: 12 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Prevalence and magnitude of transfusion-associated microchimerism |  | 1, 2 and 4 weeks, 3 and 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Microchimerism, Injuries, Leukocytes, Immunologic Techniques