title: Isolation of IgG3 from normal human sera and from a patient with multiple myeloma by using protein A-sepharose 4B.
abstract: Affinity chromatography of IgG on protein A-Sepharose was used to isolate the human subclass IgG3 from normal serum and from a patient with multiple myeloma. The isolated material was purified by chromatography on Sephadex G-150 and characterized immunochemically. Ultracentrifugation studies gave so20,w values of about 6.80 for both normal and myeloma IgG3. Approximately 54 half-cystine residues per molecule of IgG3 were obtained as judged from amino acid analysis after performic acid oxidation of the proteins. Polyacrylamide gel electrophoresis in 0.1% sodium dodecyl sulfate of the isolated and reduced material resulted in two bands corresponding to molecular weights of approximately 23,000 and 56,000, respectively. The yield of normal human IgG3 represented 1%-2% of the total IgG.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D001426:Bacterial Proteins; D002846:Chromatography, Affinity; D002850:Chromatography, Gel; D006801:Humans; D005779:Immunodiffusion; D007122:Immunoelectrophoresis; D007074:Immunoglobulin G / Q000032:analysis / Q000302:isolation & purification*; D008722:Methods; D008970:Molecular Weight; D009101:Multiple Myeloma / Q000097:blood / Q000276:immunology*; D010206:Papain; D014461:Ultracentrifugation
chemical_list: D000596:Amino Acids; D001426:Bacterial Proteins; D007074:Immunoglobulin G; D010206:Papain