Studies on Commercial Typhus Vaccines

[摘要] Commercial epidemic typhus vaccines may be fractionated by centrifugation at 5000 rpm for 1 hour, or by sedimentation in a Sharples supercentrifuge operated at 50,000 rpm with a flow rate of 10 to 15 liters per hour. The supernatant fluids from either centrifugation retained about 82 per cent of the complement fixing activity of the original vaccine, and were almost completely non-type-specific in that they reacted equally well with “epidemic” or “murine” typhus antisera. The sediments from these centrifugations, representing impure concentrates of “epidemic” rickettsiae, comprised about 13.7 per cent of the total complement fixing activity of the original vaccine. These sediments by repeated centrifugation can be washed free of impurities and of soluble antigen, to yield purified typhus rickettsiae of marked “epidemic” specificity. The yield of rickettsiae was in the order of 0.43 mg per gram of infected yolk sac (10 ml of commercial typhus vaccine).

[学科分类] 生物科学（综合）