Background Human ficolins (FCN) and mannan-binding lectin (MBL2) are pattern-recognition proteins involved in innate immunity. It has been suggested a role for MBL2 and FCN2 gene polymorphisms in the pathogenesis of recurrent, severe streptococcal infections and rheumatic carditis.
Objectives The aim of this study is to evaluate the presence of MBL2 and FCN2 gene polymorphisms (SNPs) in children with a history of acute rheumatic fever (ARF) and to investigate their possible role in ARF clinical presentation and disease course.
Methods 29 Caucasian patients with ARF were recruited with a control group of 24 healthy children. DNA was extracted for analysis of MBL2 gene (exon 1, codons: 52, 54 and 57) and FCN2 (promoter at position -4, -986 and -602).
Results We found no different distribution of the analyzed MBL2 genotypes between patients and controls. Besides, no significant association between MBL2 SNPs and ARF clinical manifestations has been demonstrated. We observed that the FCN2 GGA haplotype (particularly the G polymorphism at position -986) seems to be significantly more represented in the control group (G in -986 6,9% vs 41,7% patients vs controls, p=0,003).The FCN2 G polymorphism at position -986 (0% vs 41.7% carditis vs controls, p=0,03) is also significantly less represented in children with carditis. The FCN2 G polymorphism at position -4 (11,1% vs 50% arthritis vs controls, p=0,04) is significantly less represented in children with arthritis.
Conclusions The FCN2 GGA haplotype (especially the G polymorphism at position -986) might be considered a protective factor for ARF development. In particular, the FCN2 G polymorphism at position -986 seems to have a protective role for the development of rheumatic carditis and the FCN2 G polymorphism at position -4 seems to represent a protective factor for the development of arthritis. Further studies including larger populations and evaluating circulating FCN2 protein are needed to confirm these data.
Schafranski MD, Pereira Ferrari L, Scherner D, Torres R, Jensenius JC, De Messias-Reason IJ. High-producing MBL2 genotypes increase the risk of acute and chronic carditis in patients with history of rheumatic fever. Mol Immunol 2008.45:3827-31.
Messias Reason IJ, Schafranski MD, Kremsner PG and Kun JFJ. Ficolin 2 (FCN2) functional polymorphisms and the risk of rheumatic fever and rheumatic heart disease. Clin and Exp Immunol 2009.157:395-399.
Disclosure of Interest None declared