Umbilical cord blood transplant for adult patients with severe aplastic anemia using anti-lymphocyte globulin and cyclophosphamide as conditioning therapy

Allo-CBSCT (cord blood stem cell transplant) has been applied in six adult patients with severe aplastic anemia (SAA). Anti-lymphocyte globulin (ALG) 40 mg kg(-1) d(-1) x 3 days combined with cyclophosphamide (CTX) 20 mg kg(-1) x d-(1) x 3 days constituted a lower intensive conditioning regimen. The prophylaxis of GVHD consisted of standard CsA and MTX. Patients are all male having a mean age of 26.5 years (range 22-38), and a median weight of 55.6 kg (range 52-60 kg). Cord blood searches were all conducted at Guangzhou Cord Blood Bank. Three of six patients in our study received one unit of cord blood in a procedure, whereas for another three patients, two units of cord blood (double units) were infused at the same time in a transplant protocol. The nine units of umbilical cord blood (UCB) infused contained 1.6-10.7 x 10(7) nucleated cells/kg body weight of the recipient after thawing. HLA antigens were identical in one unit, 1 antigen mismatched in seven, 2 antigens mismatched in 1. As of February 2003, after a median follow up of 20 months (range 7-50), four patients are alive and disease free. Five patients engrafted with molecular biology analyses showing donor-recipient mixed chimerism post transplant which is stable and persistent. One patient died of severe infection in the third month from transplant and another patient died in the early stage post transplant of serious aspergillus infection without evidence of engraftment.