Partial Purification and Properties of Lupus Erythematosus Cell Promoting Factor

Summary Partial purification of the L-E cell promoting factor from gamma globulin has been achieved with the aid of a cationic cellulose exchanger. The fraction containing L-E activity is eluted at a pH of approximately 7 and a salt concentration of 0.15M. In the process of purification, total protein nitrogen content was reduced 97% nitrogen to phosphorus ratio was reduced from 44 to 14.3 without notable reduction in biologic activity. This fraction possesses the electrophoretic, sedimentation and immunologic properties of a normal gamma globulin.