The FC portion of the IgM molecule is important for structural studies and is thought to influence complement fixation and placental permeability. Prepared from plasma shown to be non reactive for HBsAg, anti-HCV, anti-HBc, and negative for anti-HIV 1 & 2 by FDA-required tests. Product Citation: Anquetil F, et al. IgM and IgA Rheumatoid Factors Purified from Rheumatoid Arthritis Sera Boost the Fc Receptor– and Complement-Dependent Effector Functions of the Disease-Specific Anti–Citrullinated Protein Autoantibodies. J Immunol. 2015 Apr 15;194(8):3664-74. doi: 10.4049/jimmunol.1402334. Epub 2015 Mar 13. Ref: Hayzer, D. J. et al. 1985. Methods Enzymol. 116, 26; Zikan, J. et al. 1973. Eur. J. Immunol. 3, 415; Plaut, A.G. et al. 1970. Proc. Natl. Acad. Sci. 65, 318.
