Clinical Status Longer than One Year Post-Transplantation in 4 Recipients of Non-T-Cell-Depleted HLA-Haploidentical Transplantation Based on Feto-Maternal Microchimerism.

The long-term presence of fetal hematopoietic cells in the maternal blood after childbirth indicates maternal tolerance to fetal inherited paternal antigens (IPA), and also that of maternal hematopoietic cells in the offspring’s blood after birth indicates mutual tolerance to non-inherited maternal antigens (NIMA) among sibling. Based on such recent feto-maternal microchimerism / tolerance theory, more than 40 cases have received non-T-cell-depleted (non-TCD) HLA-haploidentical stem cell transplantation (SCT) for various hematological malignancies in Japan. Their early post-SCT clinical courses have been reported; however, long-term outcome and quality of life of such SCT recipients are largely unknown. In our hospitals, we used non-TCD cells from haploidentical family donors for transplantation in 5 children with hematologic malignancies. Among those children, four have been alive for more than one year. Three of the 4 recipients still require prophylactic immunosuppressants for chronic GVHD. Only one case developed chronic GVHD (skin limited). Various late complications are noted in 3. Three children showed complete school attendance. Two of the three are also allowed to participate in physical exercises. These results suggest that quality of life in long-term survivors in childhood from non-TCD HLA-haploidentical SCT based on feto-maternal microchimerism seems acceptable although the numbers are still small and the follow-up period is short.

Patients characteristics

Present status of long-term survivors