Transfusion-associated microchimerism

Area of Science:

• Immunology
• Hematology

Background:

• Microchimerism involves the stable persistence of allogeneic cells.
• Blood transfusion is a newly identified cause of microchimerism.
• Transfusion-associated microchimerism (TA-MC) is distinct from fetal-maternal microchimerism.

Purpose of the Study:

• To investigate the frequency and etiology of transfusion-associated microchimerism (TA-MC).
• To understand the characteristics and potential implications of TA-MC.

Main Methods:

• Utilized advances in polymerase chain reaction (PCR) technology.
• Analyzed data from patients with severe traumatic injuries receiving blood products.

Main Results:

• TA-MC is strongly evidenced in trauma patients receiving fresh blood products after massive hemorrhage.
• Predisposing factors include pre-transfusion immunologic deficits matching donor HLA type.
• TA-MC affects ~10% of transfused injured patients, persisting for years to decades.
• It involves up to 5% of circulating leukocytes and multiple lineages, suggesting hematopoietic engraftment.

Conclusions:

• TA-MC is a common, enduring, and pronounced phenomenon following blood transfusion in specific patient populations.
• Further research into TA-MC may elucidate clinical consequences and fundamental hematologic/immunologic processes.