Immunoabsorption in an extracorporeal plasma perfusion system: in vitro studies.

A rechargeable plasma perfusion system developed to remove IgG immunoglobulins is described. Partially purified protein A was covalently bonded on two separate carriers, Sepharose 6MB and carboxyl acrylic beads. Plasma from a patient with IgG multiple myeloma was perfused through the Sepharose-protein A column, and this resulted in a maximum removal of 177% of the estimated removal capacity of the column. Plasma from the same source was perfused through the acrylic bead-protein A column and yielded an average of 220% of the estimated removal capacity of the column. In addition, plasma from a normal subject and from six patients with various autoimmune diseases was perfused through the Sepharose-protein A column, and varying percent removal was obtained. A detailed procedure for covalent coupling of purified protein A to carboxylated acrylic beads is also given.