Department of Bacteriology and Immunology, Harvard University Medical School, Boston.
J Exp Med. 1931 Feb 28;53(3):325-31. doi: 10.1084/jem.53.3.325.
We have adduced evidence that guinea pigs can be completely or partially protected by three injections of typhus tunica material in which there are moderate numbers of Rickettsiae, treated for from 24 to 48 hours with a 0.2 per cent formalin solution. We believe that the immunization is due to the presence of the Rickettsiae, since in our preceding experiments we have satisfied ourselves that these organisms are the true etiological factors of the disease. For the reasons stated above, we believe that the formalinized vaccine does not contain living, but attenuated organisms, and that the immunizing effect is the result of treatment with formalin-killed Rickettsiae. This point, however, we admit, is not absolutely determined. These experiments, together with the results obtained in the concentration of Rickettsia material by the diet method of reducing resistance as described in the paper which follows, furnish a hopeful method and a reasonable theoretical basis for a procedure of active immunization against this disease in human beings.
我们已经提出证据表明，豚鼠可以通过三次注射含有适量立克次体的恙虫病囊膜材料得到完全或部分保护，这些材料经过 24 至 48 小时用 0.2%甲醛溶液处理。我们认为免疫是由于立克次体的存在，因为在我们之前的实验中，我们已经确信这些生物体是这种疾病的真正病因。基于上述原因，我们认为甲醛化疫苗不含有活的，但减毒的生物体，免疫效果是甲醛杀死立克次体处理的结果。然而，我们承认这一点并不是绝对确定的。这些实验，以及在后面的论文中所描述的通过降低抵抗力的饮食方法浓缩立克次体材料的结果，为人类针对这种疾病的主动免疫提供了一个有希望的方法和合理的理论基础。
