Graft survival assessment of MN genotype after allogeneic transplantation of hematopoietic stem cells of umbilical cord blood.

ABSTRACT

OBJECTIVE: To establish a simple and practical method to assess the outcome of allogeneic transplantation of hematopoietic stem cells from umbilical cord blood. METHODS: The DNA was extracted from the samples collected from the donor and the receptor separately before and 15 and 300 d after transplantation. MN genotype was determined by PCR with sequence-specific primers (PCR-SSP) with the 2 pairs of specific primers designed and synthesized on the basis of reported MN gene sequence. RESULTS: The donor was identified as having NN genotype while the recipient shown to be MM genotype. MN genotype was detected in the recipient (mixed chimerism) at 15 d after transplantation. The genotype reversed to NN (donor origin) at 300 d after transplantation. The NN gene, as the donor's marker and evidence for the graft survival analysis, was eventually identified in the recipient. CONCLUSIONS: With MN genotype test to confirm the graft survival, early engraftment monitor of allogeneic umbilical cord blood transplantation is ensured, with the advantages of better sensitivity and requiring small amount of sample (0.2 ml). It may also facilitate subsequent therapeutic decisions.