Diagnostic potential of mannose binding lectin (MBL) gene polymorphism in rheumatoid arthritis patients

Background: Rheumatoid arthritis (RA) is a chronic joint inflammatory condition which can result in damage to the cartilage and bone. RA susceptibility and pathophysiology have been associated with activation of the innate immune pathway. The mannose binding lectin (MBL) activates the complement system and a key component of innate immunity. Aim of the work: To study the diagnostic potential of MBL2 genetic variants and flowing serum MBL levels and study their probable function as a marker for RA susceptibility and relation to disease activity. Patients and methods: The study included 60 RA patient and 15 age and sex matched control. Detection of MBL serum level and MBL2 gene type and polymorphism by polymerized chain reactin (PCR). The visual analogue-scale (VAS) and disease activity score (DAS28) were assessed. Results: The 60 patients; 51 females and 9 males (F:M 5.7:1) with mean age of 42.2 +/- 8.03 years (36-51) and disease duration 5 +/- 2.8 (3-7 years). The mean of MBL level in the patients was significantly higher (92.7 +/- 78 ng/dl) than in the control (83.8 +/- 62.9 ng/dl) (p < 0.01). 33 (55%) had a low level MBL and 27 (45%) moderate level. 14 (93.3%) of the control had low levels and 1 (6.7%) moderate. MBL2 genotype was B (48.3%), D (50%) and C (1.7%) in RA but in the control only 13.3% were positive with type D. The MBL level significantly correlated with the RF (r = 0.3, p = 0.02). Conclusion: There was a strong correlation between MBL2 gene alleles (B and D) and MBL2 protein level and susceptibility for RA in Egyptian populations. (C) 2020 Egyptian Society of Rheumatic Diseases. Publishing services provided by Elsevier B.V.