New method for the specific clearance of antibodies using antigens linked to a collagen film

A new type of immunoadsorbent, derived from a commercial haemodialysis module, has been designed. The dialysis membranes were replaced by bovine collagen membranes on which a given antigen had been linked by covalent binding. First, these membranes were tested in vitro: they were placed in contact with a given volume and concentration of antiserum to define their capacity to retain antibodies. Second, they were stacked in a modified haemodialyzer for antibody extraction ex vivo in dogs: the blood of immunized animals was passed over the immunoadsorbent and recirculated after either partial or total removal of antibodies. The degree of purification is related to the area of the membranes used and to the volume of blood to be purified.