How does Graft Versus Host Disease (GVHD) from cord blood compare to other sources of stem cells?
GVHD is less severe with cord blood than with bone marrow. In a study where all patients received an HLA-matched transplant from a sibling, and the results were controlled for age, the relative risk of cord blood versus bone marrow was 0.41 for acute GVHD and 0.35 for chronic GVHD. The accepted explanation is that cord blood carries much less GVHD than bone marrow because the newborn baby is “immunologically immature” — ie., the immune system has not had time to be exposed to various foreign bodies and develop reactions against them. Reference: • Rocha, V., et al. NEJM 2000;342:1846-54 In late 2003 it was announced that a patient’s risk for GVHD is also governed by genetics: those patients who carry the gene “C/C interleukin-10” are 2.6 times more likely to get GVHD after a perfectly matched sibling transplant than patients who carry the A/A genotype. Reference: • Lin et al.
