BACKGROUND: Donor/recipient mixed chimerism has been reported to be associated with an increased risk of graft failure in patients with beta-thalassemia given a bone marrow transplant. We investigated the relationship between the degree of mixed chimerism over time and clinical outcome of children undergoing cord blood transplantation for beta-thalassemia. DESIGN AND METHODS: Twenty-seven consecutive children given a cord blood transplant from a related donor were analyzed by short tandem repeat polymerase chain reaction and their chimerism results were compared with those of 79 consecutive patients who received a bone marrow transplant from either a relative (RD-BMT, n=42) or an unrelated donor (UD-BMT, n=37). Cord blood and bone marrow recipients received comparable preparative regimens. RESULTS: All cord blood recipients engrafted and displayed mixed chimerism early after transplantation; 13/27 converted to full donor chimerism over time, while 14 maintained stable mixed chimerism; all patients are alive and transfusion-independent. Twenty-four of the 79 bone marrow-recipients (12 UD- and 12 RD-BMT) exhibited full donor chimerism at all time points examined, 4/79 (2 UD- and 2 RD-BMT) did not engraft and 51/79 (23 UD- and 28 RD-BMT) displayed mixed chimerism at the time of hematologic reconstitution. Forty of 51 bone marrow recipients with mixed chimerism converted to full donor chimerism (17 UD- and 23 RD-BMT), 3/51 maintained stable mixed chimerism (1 UD- and 2 RD-BMT), while 8/51 (5 UD- and 3 RD-BMT) progressively lost the graft, and became transfusion-dependent again. CONCLUSIONS: Mixed chimerism is a frequent event and does not predict the occurrence of graft failure in children with beta-thalassemia given a cord blood transplant from a relative.
BACKGROUND:Donor/recipient mixed chimerism has been reported to be associated with an increased risk of graft failure in patients with beta-thalassemia given a bone marrow transplant. We investigated the relationship between the degree of mixed chimerism over time and clinical outcome of children undergoing cord blood transplantation for beta-thalassemia. DESIGN AND METHODS: Twenty-seven consecutive children given a cord blood transplant from a related donor were analyzed by short tandem repeat polymerase chain reaction and their chimerism results were compared with those of 79 consecutive patients who received a bone marrow transplant from either a relative (RD-BMT, n=42) or an unrelated donor (UD-BMT, n=37). Cord blood and bone marrow recipients received comparable preparative regimens. RESULTS: All cord blood recipients engrafted and displayed mixed chimerism early after transplantation; 13/27 converted to full donor chimerism over time, while 14 maintained stable mixed chimerism; all patients are alive and transfusion-independent. Twenty-four of the 79 bone marrow-recipients (12 UD- and 12 RD-BMT) exhibited full donor chimerism at all time points examined, 4/79 (2 UD- and 2 RD-BMT) did not engraft and 51/79 (23 UD- and 28 RD-BMT) displayed mixed chimerism at the time of hematologic reconstitution. Forty of 51 bone marrow recipients with mixed chimerism converted to full donor chimerism (17 UD- and 23 RD-BMT), 3/51 maintained stable mixed chimerism (1 UD- and 2 RD-BMT), while 8/51 (5 UD- and 3 RD-BMT) progressively lost the graft, and became transfusion-dependent again. CONCLUSIONS: Mixed chimerism is a frequent event and does not predict the occurrence of graft failure in children with beta-thalassemia given a cord blood transplant from a relative.
Authors: Rudolph Kirk R Schultz; Kevin Scott Baker; Jaap J Boelens; Catherine M Bollard; R Maarten Egeler; Mort Cowan; Ruth Ladenstein; Arjan Lankester; Franco Locatelli; Anita Lawitschka; John E Levine; Mignon Loh; Eneida Nemecek; Charlotte Niemeyer; Vinod K Prasad; Vanderson Rocha; Shalini Shenoy; Brigitte Strahm; Paul Veys; Donna Wall; Peter Bader; Stephan A Grupp; Michael A Pulsipher; Christina Peters Journal: Biol Blood Marrow Transplant Date: 2013-07-21 Impact factor: 5.742
Authors: Natasha M Fewkes; Aviva C Krauss; Martin Guimond; Joanna L Meadors; Stefania Dobre; Crystal L Mackall Journal: Blood Date: 2010-03-15 Impact factor: 22.113