Journal of Iranian Blood Transfusion

  Abstract

 Background and Objectives

 GVHD occurs in 20–40% of recipients of HLA-matched sibling donor grafts. A number of studies suggest that polymorphism in cytokine genes influence susceptibility to post-BMT complications. One of the cytokine gene family (IL-1RN) encodes IL-1 receptor antagonist (IL-1Ra), an anti-inflammatory molecule that competes for receptor binding with IL-1α and IL-1β. The overall contribution of IL-1 to the proinflammatory response depends on the balance between these three molecules. In this study, we decided to evaluate the polymorphisms of IL-1Ra gene that might influence the outcome of BMT.

 Materials and Methods

 In this cohort study, patients' (n = 175) and donors' (n = 175) DNA from a total of 350 human leucocyte antigen (HLA)-identical sibling allogeneic BMTs were analysed. IL-1Ra gene polymorphism was studied by PCR-VNTR method. PCR products were then visualized by electrophoresis in 2% agarose gel. Then, the correlation between donor and recipient genotype and GVHD grade for their respective transplant was assessed.

 Results

 The frequency of the aGVHD grades was divided to grade 0 (38.3%), grade I (17.7%), grade II (27.4%), grade III (13.7%), grade IV (2.9%). Correlation between donor and recipient genotype and GVHD grade for their respective transplant was assessed. We observed no significant correlation between the IL-1Ra polymorphism and incidence of aGVHD, although possession of the allele 2 in the individual genotype was associated with less severe acute GVHD.

 Conclusions

 The observed allele frequencies were different from those previously reported. None of the polymorphisms showed association with the presence of acute GVHD. However, presence of allele 2 showed association with aGVHD. If the recipient possesed allele 2, the probability of aGVHD was 46% and in the absence of allele 2, it was 62%. Recipient age, donor age, recipient disease particularly thalassemia were the most remarkable risk factors for acute GVHD.

 Key words : Bone marrow transplantation, Genotype, Graft Versus Host Disease