The Effect of Antigen Administration on the Behavior of I131 Labelled Rabbit Anti-Ovalbumin in Mice

Abstract
A considerable literature has developed on the use of I131 trace-iodinated rabbit antibodies as indicators for the in vivo detection of antigenic proteins (1–6). The criterion employed in these studies has been the demonstration of selective localization of radioactivity in tissues as determined by radioautography and tissue radioactivity. Quantitative evaluation of results obtained with these methods are limited (7, 8), and the techniques in common use are capable of providing only a semiquantitative estimation of the antigen-antibody reaction. Interpretation of such data is also complicated by the inability to ascertain the contribution of labelled protein within the vascular space of a tissue to the total radioactivity determined in that tissue. In the present report a metabolic balance study of radioactivity introduced as an I131 trace-labelled antibody was applied to the problem of in vivo antigen-antibody reactions using I131 rabbit antibodies in mice.