Macroglobulins in Rheumatoid Arthritis and Other Diseases

Abstract

A report of our earlier studies of the rheumatoid factor (RF) was published in this Journal. 1 In the present paper we want to refer to our investigations by means of zone electrophoresis in 1954 to 1955. 2 -5 We found that the RF followed the fast migrating γ-globulins, to which group the γ-macroglobulins belong. But it was not until December 1956 that the opportunity arose to determine the sedimentation coefficient of the RF. This was done first at the Nobel Institute of Biochemistry (Hugo Theorell), and later in cooperation with S. Hedman at the Gustaf V Research Institute. Our investigations have shown that the sedimentation coefficient of the RF lies mostly between 18.2 and 18.8 S 20W (Svedberg units). As reported in previous publications, the RF has been isolated in pure form by a special procedure (see below). As criteria of purity, the requirements have been that only one