Anatomic and Histologic Changes in Rabbits with Experimental Hypersensitivity Treated with Compound E and ACTH

The Mechanism of Action of Cortisone in Experimental Hypersensitivity

“…5 of 7 control animals (71 per cent) and 3 of 5 cortisone-treated animals (60 per cent) which developed circulating antibody responded with an Arthus reaction to the injection of albumin (Tables I and II). These results corroborate previous work which indicated that suppression of the Arthns reaction by cortisone requires that the appearance of serum antibody be inhibited (5)(6)(7)(8).…”

“…In both groups of animals, there were some animals which eliminated the antigen slowly, probably owing to failure to develop antibody, and others which had eliminated all of the antigen and showed free serum antibody. Approximately equal numbers of animals in each group (7 of 24 controls --The anatomic alterations produced by cortisone have been described in a previous publication (13). Similar alterations were encountered in the present experiment.…”

“…In a comparable way, an inhibition of the allergic inflammatory reaction by cortisone is seen only when the stimulus is small, and is lost when the reaction is severe. Consequently, complete inhibition of the Arthus reaction, in contrast to that of the visceral allergic lesion, requires an additional effect of cortisone, namely a suppression of the appearance of antibody in the serum (7).…”

“…Further, the quantitative immunological data clearly demonstrate that cortisone, in the dosage employed, had no effect on the "immune" phase of antigen elimination or on the subsequent appearance of circulating antibody. In previous studies (6,7) in which sensitization of rabbits was produced by daily intracutaneous injections of small amounts of antigen rather than by a single intravenous injection of a large amount of antigen, cortisone in the same dosages markedly suppressed the appearance of antibody. It is clear that the effect of cortisone depends on the dosage, multiplicity, or route of antigen administration.…”

“…Inhibition of antibody formation, interference with antigen-antibody combination, and suppression of the inflammatory reaction resulting from antigen-antibody combination are possible explanations. In previous studies (5,7) it was demonstrated that cortisone and ACTH suppress the appearance of circulating antibody in rabbits receiving intracutancous injections of antigen. Further, it was shown that the inhibition of the Arthns reaction by cortisone, both in rabbits (7) and in guinea pigs (8), depended on the hormonal suppression of circulating antibody.…”