[Microchimera. New thought process for pathogenesis of systemic scleroderma].

Persistent cellular microchimerism might play a role in the pathogenesis of systemic sclerosis (SSc). Microchimerism results from the traffic of fetal cells through the placenta during pregnancy into the maternal circulation and their survival due to HLA class II compatibility. In female SSc patients the presence of fetal CD3-positive T-cells in the maternal circulation and of fetal cells in the affected skin tissue has been identified through y chromosome specific DNA sequences. The persistent microchimerism might cause SSc in certain patients by initiating a fetal anti-maternal Graft-versus-host-like response.