[Evaluation of immunosuppressive acid protein (IAP) in patients with rheumatoid arthritis]

Immunosuppressive acidic protein (IAP) is evaluated to be a useful parameter for the observation of the clinical course of patients with cancer, who are frequently associated with an increment of serum IAP levels. And also, immune complex diseases such as rheumatoid arthritis (RA), SLE and so on, have been described to produce immune-complex and, consequently, to generate IAP in vivo. Our study focuses on correlations of the IAP values with acute phase reactants, chronic phase reactants and grading of bone stages in patients with RA. Serum IAP showed the positive relationships with grading of bone stages, erythrocyte sedimentation rate (ESR), CRP, RF, RAHA, beta 2-microglobulin (BMG) and IgA in RA. Serum IAP was influenced by deterioration of bone pathological change. The more progressed pathological change of bone, the more increased serum IAP levels. It seems likely that there exist the similar mechanisms with production of IAP and parts of acute and chronic phase reactants and also, serum IAP level may be a useful parameter to predict bone pathological change in patients with RA.