Microchimerism and the causation of scleroderma.

The application of molecular techniques to the study of human pregnancy has resulted in the recognition that there is bi-directional cell traffic during pregnancy. Recent studies indicate fetal progenitor cells can persist in the maternal peripheral blood for decades after childbirth. Scleroderma is increased in women, has a peak incidence following childbearing years, and has clinical similarities to chronic graft-versus-host disease that occurs after allogeneic stem cell transplantation. This paper explores the idea that microchimerism is involved in scleroderma and considers insights gained from transplantation biology in seeking to understand how microchimerism might contribute to the pathogenesis of scleroderma. Chimerism means that a body contains cell populations derived from different individuals and microchimerism low levels of chimerism. Although highlighted in the study of scleroderma, microchimerism is also implicated in selected other autoimmune disorders.