[Possibilities for using the analytical ultracentrifugation method for determining circulating immune complexes in rheumatic diseases].

Analytical ultracentrifugation was used to study circulating immune complexes in 78 patients suffering from different rheumatic diseases. Using this method immune complexes were mostly detectable in patients with rheumatoid arthritis. This correlated with the disease activity, roentgenological stage of articular involvement, development of the systemic manifestations associated with rheumatoid vasculitis. Demonstration of immune complexes by analytical ultracentrifugation was found to correlate on the whole with the presence in sera of high titers of rheumatoid factors and immune complexes according to the PEG method data.