In vivo and In vitro Studies of Labeled Antibodies Against Rat Kidney and Walker Carcinoma. ∗

Abstract

Summary

An in vitro method is described for demonstrating the binding by rat organ homogenates of I¹³¹ labeled antibodies produced by rabbits immunized with particular rat organs. By this test anti-kidney antibodies show specificity for kidney compared with other rat tissues, and anti-Walker rat carcinoma 256 antibodies specificity for this tumor tissue. These data are compared with I¹³¹ distributions found after injection of these antibodies by various routes into living rats. The results suggest that nearly all of these antibody molecules are also general anti-rat antibodies in that they are bound by components of other rat tissues. Such factors as relative circulation rates, blood vessel permeability to proteins, and intracellular or extracellular location of antigens, as well as relative organ specificity of antibodies as demonstrated by in vitro experiments, are probably therefore important in determining the localization of such antibodies in animal injection experiments.