Measurement of the ‘fast’ or complexed form of α2 macroglobulin in biological fluids using a sandwich enzyme immunoassay

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Abstract

A sandwich enzyme immunoassay has been developed for measuring the ‘fast’ or complexed form of α2 macroglobulin using a complex-specific monoclonal antibody. The working range of this assay is 1.5–15 μg/1 and is suitable for use with various biological fluids. Using this assay the normal plasma levels were found to range from 4.2 mg/1 to 14.4 mg/1 (0.17%–0.70% of total α2 macroglobulin) with a mean value of 7.6 mg/1 ± 2.6 (0.37% ± 0.12% of total α2 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.

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