EXPERIMENTAL STUDY OF THE «DOSE - EFFECT» RELATIONSHIP DURING IMMUNIZATION WITH STAPHYLOCOCCAL TOXOID

Abstract

We set ourselves the task of studying the "dose-effect" relationship when mice immunized with staphylococcal toxoid were infected with different strains of staphylococcus. The animals were immunized subcutaneously twice with a 14-day interval with purified toxoids of series No. 22 (containing 20 EC/ml) and No. 29 (12 EC/ml) and with highly purified toxoid of series No. 41 (30 EC/ml). All preparations were completely sorbed on Al(OH)3. The experiments carried out allow us to consider, albeit with certain reservations, that in the twofold immunization of white mice with staphylococcal toxoid it is advisable to take an antigen dose equal to 1 EC for each vaccination. The author studied the dependence of the immunological effect on the dose of purified staphylococcal toxoid sorbed on Al(OH)3 in the twofold immunization of white mice. Antitoxin titers in the blood serum and the resistance of mice to infection with the microbial culture of 7 different staphylococcal strains were studied. A direct close correlation existed between the toxoid dose and the antitoxin level in the serum of the immunized animals. On the contrary, no pronounced correlation was found between the toxoid dose and the resistance of the mice to infection with the microbial culture of staphylococci. The resistance of the animals depended to a considerable extent on the properties of the strains used for infection. In experiments on studying the resistance of immunized mice to staphylococcal culture it is apparently advisable to take 1 BU (binding unit) of toxoid for each immunization.