SYSTEMIC LUPUS ERYTHEMATOSUS. CRYOPRECIPITATION OF SERA

Abstract

Sera of normal human subjects, when refrigerated (O to 40 C), form negligible quantities of precipitate. A variety of pathologic states have been associated with serum cryoprecipitation: myelomatosis, Waldenstr6m's macroglobulinemia, lymphosarcoma, kala azar, bacterial endocarditis, rheumatoid arthritis, periarteritis, and systemic lupus erythematosus (SLE) (1). Lerner, Watson, and Barnum suggested the term "cryoglobulins" for cold-precipitable elements of sera and established quantitative criteria for their studies (2, 3). When serum cryoproteins have been characterized, the majority have been homogeneous in electrophoretic and sedimentation studies. Cryoproteins of myeloma sera usually consist of the respective paraproteins. The cryoproteins separating from sera with "rheumatoid factor"