Expression of phosphatidylinositol anchored membrane proteins in paroxysmal nocturnal haemoglobinuria after bone marrow transplantation.

A 20-year-old male with severe bone marrow failure associated with paroxysmal nocturnal haemoglobinuria (PNH) underwent an allogeneic bone marrow transplantation (BMT). Flow cytometric analysis of phosphatidylinositol (PI) anchored membrane proteins prior to BMT showed a markedly reduced expression of monocyte CD14 and neutrophil CD16 molecules. On day +17 after BMT expression of both antigens reached normal values and remained stable throughout a follow-up period of 10 months, thus confirming the eradication of the PNH clone. To date, this is the first case in which normal expression of PI-anchored proteins after BMT is reported.