Transplantation of bone marrow cells with changed haemoglobin type

Haemoglobin was used as a marker for the detection of radiation chimera in rats. After a single blood loss, the synthesis of haemoglobin type had changed, as observed in peripheral blood one week after bleeding. After one month the haemoglobin pattern was the same in the experimental rats and in the control animals. Twenty-four hours before bone marrow transplantation the donors were bled. Haemoglobin synthesis had changed also in the recipients. In contrast with a single blood loss, this change of haemoglobin type persisted as observed one year after transplantation. The cells with changed synthesis can repeatedly be retransplanted.