Measurement of the 'fast' or complexed form of alpha 2 macroglobulin in biological fluids using a sandwich enzyme immunoassay.

A sandwich enzyme immunoassay has been developed for measuring the 'fast' or complexed form of alpha 2 macroglobulin using a complex-specific monoclonal antibody. The working range of this assay is 1.5-15 micrograms/l and is suitable for use with various biological fluids. Using this assay the normal plasma levels were found to range from 4.2 mg/l to 14.4 mg/l (0.17%-0.70% of total alpha 2 macroglobulin) with a mean value of 7.6 mg/l +/- 2.6 (0.37% +/- 0.12% of total alpha 2 macroglobulin). Elevated levels were seen in plasma samples taken on the day of admission from patients with acute pancreatitis and in some synovial fluid samples from patients with various arthritides.