Analysis of IL-1β, TGF- Β, Il-5, ACE and PTPN22 Gene Polymorphisms and GEN Expression Levels in Turkish Chlidren with IgA Vasculitis

Abstract

Abstract Objective; Immunoglobulin-A vasculitis (IgAV) is an inflammatory vascular disease that affects small blood vessels. This study was performed with the aim of identifying an association between PTPN22+788G>A (rs33996649), TGF-β-509C>T (rs18004069), IL-1β-511C>T (rs16944), IL-5-746C/T (rs2069812), ACE I/D (rs4646994) gene polymorphisms and susceptibility to IgAV. Method; A total of 53 IgAV patients and 50 healthy controls were enrolled. PTPN22, TGF-β-, IL-1β gene polymorphisms, ACE gene I/D polymorphism and mRNA expression levels were analyzed by the PCR-RFLP method, allele specific PCR and real-time PCR with TaqMan kits, respectively. Results; PTPN22, TGF-β, IL-1β, IL-5, ACE variants showed no genotype or allele differences between IgAV patients and controls. Increased levels of IL-1β and TGF-β mRNA expressions were observed in IgAV patients. In addition, patients with IL-1β AG genotype showed signicantly increased amounts of arthritis than non-AG (AA+GG) patients (p=0.004). Likewise, age at disease onset was found to be significantly differed in IgAV patients according to the presence of TT genotype of TGF-β (p=0.047). Conclusion; Polymorphisms in PTPN22, TGF-β-5, IL-1β and ACE genes are unlikely to confer susceptibility to IgAV and also this is the first study to report a lack of association between IL-5-746C/T and a susceptibility to IgAV. However, the presence of the AG genotype of IL-1β is associated with a susceptibility to IgAV-related arthritis. This is also the first study to report a significant increase in serum mRNA levels of IL-1βand TGF-β in IgAV patients supporting a susceptibility to IgAV in childhood.