Apoptosis inhibitor of macrophage/CD5L is associated with disease activity in rheumatoid arthritis.

OBJECTIVES

To investigate the association between apoptosis inhibitor of macrophage (AIM) and disease activity in patients with rheumatoid arthritis (RA).

METHODS

In this study, concentrations of serum AIM in 110 RA patients, 38 patients with osteoarthritis (OA) and 50 sex- and age-matched control subjects were determined by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Serum AIM concentrations in RA patients were dramatically higher than those from patients with OA or healthy controls. The levels of synovial fluid AIM displayed a significant increase as compared with OA patients. More importantly, AIM levels were significantly correlated with RA disease activity features such as ESR, CRP and DAS28. The predictive value of AIM on high disease activity was superior to those of CRP and ESR. A noteworthy correlation in our study was observed between the serum AIM levels and laboratory parameters, particularly serum lipids. Furthermore, serum AIM levels could be significantly down-regulated after effective integrative treatment.

CONCLUSIONS

AIM may serve as a novel sensitive biomarker to assist disease activity assessment and monitor therapeutic effects in active RA patients.