ABSTRACT
Allogeneic bone marrow transplantation leads to a state of chimerism, i.e. the presence of cells from two different individuals.
1) “Complete chimera” is when hematopoietic cells are entirely donor in origin. 2) “Mixed chimeras” is when both donor and host hematopoietic elements are
detected. 3) “Split chimera” has been used in situations where lymphoid and myeloid com
ponents are discordant in origin of cells. II) INDICATIONS FOR EVALUATING CHIMERISM
1) Evaluate origin of lymphoid and hematopoietic cells in patients with inad equate marrow function. In particular, evaluate whether rejection has occurred in patients who are candidates for a second transplant. In cases of poor graft func tion, determining donor or host origin of hematopoietic elements, and particu larly the lymphoid cells, is often critical to determining subsequent treatment options.
