Background: Interleukin-7 (IL-7) is a hematopoietic cytokine essential for T-cell development in the thymus and for the maintenance of peripheral T cells. A previous study of single nucleotide polymorphisms in the exons of IL-7 receptor α-chain (IL-7Rα) in a Danish cohort of patients undergoing allogeneic stem-cell transplantation (SCT) identified donor genotype GG at rs1494555 as a risk factor for treatment-related mortality (TRM) after SCT.
Methods: In this validation study, 116 British and French SCT patients and their donors were investigated by sequence-specific primer polymerase chain reaction.
Results: Both donor rs1494555GG genotype and the tightly coupled rs1494558TT genotype were significantly associated with grade 3 to 4 acute graft versus host disease. Although both genotypes tended to be associated with increased TRM, this did not translate into altered overall survival.
Conclusion: The present data indicate that the IL-7 pathway is associated with alloreactivity in SCT, which is in line with the previously observed association between IL-7Rα single nucleotide polymorphisms and TRM.