Frederick G. Germuth

Effect of 17-Hydroxy-11-Dehydrocorticosterone (Compound E) and of ACTH on Arthus Reaction and Antibody Formation in the Rabbit

Summary 1. The effects of compound E and ACTH on experimental hypersensitivity of the Arthus type and on antibody production in the rabbit are described. Both compound E and ACTH inhibited sensitization to repeated intracutaneous injections of crystalline egg albumin. Moreover the inhibition produced by compound E was much greater than that obtained with ACTH; with compound E sensitization was almost completely prevented in all of the 8 animals tested. 2. The data indicate that the inhibitory effect of compound E and ACTH on the development of the Arthus state results from the ability of these hormones to suppress antibody formation. As shown by antibody nitrogen determinations, compound E and ACTH suppressed antibody formation by an average of 100 and 50% respectively. 3. In contrast to their striking effect on the production of the active Arthus reaction, compound E and ACTH had no effect on the passive local Arthus reaction, when antibody is supplied to the animal. Thus, the capacity of the animal to react to antibody-antigen combination in the tissues is not altered by treatment.

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

Summary The experimental data indicate that Compound E markedly suppresses the pathological alterations of the Arthus reaction ordinarily produced in the rabbit by repeated injections of crystalline egg albumin. The adrenocorticotrophic hormone exerted a decidedly less marked effect. 2. Treatment with Compound E and ACTH produced atrophy of the lymphoid tissues, including the thymus and spleen, and a lymphocytopenia. These alterations were greater with Compound E and in addition, in the animals treated with this hormone, there were extensive deposition of glycogen and fat in the liver, a lipemia and focal necrosis of skeletal muscle. In the animals treated with Compound E the adrenals were small while in those treated with ACTH, the adrenals were enlarged but lacking in lipoid.

Influence of cortisone on experimental hypersensitivity and circulating antibody in the guinea pig.

Summary 1. Large doses of cortisone failed to protect guinea pigs against active or passive anaphylactic shock. These results are in agreement with those of other investigators (3,4). 2. Treatment with this hormone during period of active sensitization diminished the intensity of the Arthus reaction and the quantity of circulating antibody produced. Neither of these effects was as extensive as those observed in rabbits following the administration of comparatively smaller doses of cortisone (1,2) Similarly, the anatomic changes produced by cortisone were less striking in the guinea pig than in the rabbit (8). These findings suggest that the guinea pig is considerably more resistant to the action of cortisone. The failure of cortisone to abolish the active Arthus reaction and possibly its failure to alter active anaphylactic shock might have been related to the incomplete suppression of circulating antibody under the experimental conditions employed.

Some quantitative aspects of passive anaphylaxis in pertussis-vaccinated mice.

Summary 1. Pertussis vaccine significantly increased the susceptibility of mice to passive anaphylaxis. Two lots of anti-bovine-serum-albumin rabbit serum containing 0.816 and 2.52 mg antibody N per ml, respectively, were used. With each, the response was graded in relation to amount of antibody injected and reproducible titrations of the SD50 were obtained. The SD50 values for the respective sera were 4.06 ± .27 and 7.9 ± 1.03 mg N/ kg, respectively. Significance of the difference was not definitely established. In non-vaccinated mice, even with several fold increases in antibody, the highest incidence of shock, was around 50% and frequently the response was irregularly graded. 2. Within a range of dosage of pertussis vaccine that varied as much as 16 fold and which significantly affected the histamine LD50, the passive anaphylactic SD50 values of the sera were not significantly altered. 3. Comparable anaphylactic sensitivity was observed when a serum was; administered either 48, 24, or 6 hours before the antigen. Besides the theoretical significance, the findings indicate that mice treated with pertussis vaccine may be useful in anaphylaxis studies.