Disease Activity Score 28 (DAS28) isthe most widely used method
for rheumatoid arthritis(RA) disease activity evaluation. However, it
may not reflect disease activity accurately being a subjective tool
dependent on patient's self-health assessment and evaluation of
swollen and tender joint counts. Therefore, finding a suitable blood
genetic marker for accurate monitoring of RA disease activity has
become essential. Therefore, the aim of this study was to assess miR-
146a and TLR4 expression in PBMCs of RA patients and to study
their value as potential molecular biomarkers for RA disease activity
in comparison to DAS28 score. This study was conducted on 51 RA
patients and 15 age and sex matched healthy subjects as control group.
The relative gene expression levels of miR-146a and TLR4 were
determined by reverse transcriptase quantitative real time polymerase
chain reaction. There were statistically significant differences between
patients and healthy controls as regards miR-146a and TLR4
expression. In addition, statistically significant differences were
observed between different patients' subgroups as regards miR-146a
and TLR4 expression. Moreover, miR-146a and TLR4 expression
levels showed significant positive correlationswith those of morning
stiffness durations, tender joints counts, swollen joints counts, visual
analogue scale values, erythrocyte sedimentation rates, CRP, Anti-
CCP antibody and DAS28.MiR-146aillustrated the best performance characteristics particularly in differentiating between high and moderate disease activity grades, showing highest sensitivity and
specificity.Furthermore, there was a statistically significant increase in
the expression levels of miR-146a and TLR4 in PBMCs of RA
patients with ankles and/or feet joints involvement, as compared with
those without involvement.Conclusion: MiR-146a and TLR4 were
overexpressed in PBMCs of RA patients and were correlated with
disease activity and radiographic progression especially miR-146a.