Background: Rheumatoid arthritis (RA) is the most common autoimmune inflammatory
arthritis, with a lifetime prevalence of up to 1% around the world. It is characterized by
an inflammatory polyarthritis that preferentially affects the small joints leading to joint
damage and eventual deformity and disability, and can also present with extra-articular
manifestations. Micro RNA (miRNA) is a class of non-coding RNAs which negatively
regulate messenger RNA (mRNA) expression. Objective: To evaluate the expression of
miRNA-223 in rheumatoid arthritis (RA) patients and its potential association with
disease activity and severity. Methodology: Blood samples from 35 patients with RA,
according to the classification criteria of the American College of Rheumatology/
European League against Rheumatism (ACR/EULAR) for RA1
and 35 apparently healthy
volunteers as controls were allocated. Real-time PCR was used to determine the
expression levels of miRNA 223. Results: miRNA 223 expression level was significantly
higher in RA group compared with controls (RA group: 2.19± 1.28 vs 1.0± 0.02; P