In vitro studies on antibodies to intrinsic factor.

  • 1 July 1967
    • journal article
    • Vol. 2  (4) , 399-413
Abstract
In vitro experiments on anti-intrinsic factor antibodies in the sera from patients with pernicious anaemia are reported. These studies show that antibody activity which blocks the binding of B12 by intrinsic factor (antibody I) is on a different molecule from that which unites with intrinsic factor-B12 (antibody II), and that antibody II unites with either intrinsic factor (IF) or intrinsic factor-B12 (IFB12). Antibody I exchanges readily with the B12 of IFB12. The complex of IF and antibody I will absorb antibody II. The data are interpreted as supporting the conclusion that IF has at least two antigenic regions. An unusual type of antibody activity is also reported. This antibody appears to stabilize B12 on IF, so that exchange of B1259Co or antibody I with the B1257Co of IFB1257Co is inhibited. This antibody also forms a complex with IFB12 which is of a different size from other antibody II–IFB12 complexes.