Plasma levels of beta-2 microglobulin in rheumatoid arthritis.
A simple and inexpensive method is described for the determination of beta 2-microglobulin (beta 2-MG) by enzyme-amplified single radial immunodiffusion. The values obtained with this method correlate well with those determined by means of a commerical RIA kit. Using the immunodiffusion method we have measured the plasma levels of beta 2-MG in 135 patients with rheumatoid arthritis (RA) and normal