The adjuvant effects of a tubercle bacillary lipid and lecithin: The immunization of mice by tetanus toxoid

Abstract

Summary Mice were immunized by a single subcutaneous injection of tetanus toxoid (a) alone (b) with a tubercle bacillary lipid or (c) with a synthetic lecithin. The tubercle bacillary lipid or the lecithin were injected at the same time as the toxoid. The mice were challenged fourteen days later with a lethal dose of tetanus toxin. The tubercle bacillary lipid augmented the protection given to the mice if it were injected mixed with the toxoid, but not if it were injected by the intraperitoneal route. The augmenting effect appeared to be significant only with doses of toxoid that were effective alone, and increased with increasing dosage of the lipid Lecithin displayed a significant adjuvant effect only when injected in large doses together with the toxoid.