Ascher M S, Oster C N, Harber P I, Kenyon R H, Pedersen C E
J Infect Dis. 1978 Aug;138(2):217-21. doi: 10.1093/infdis/138.2.217.
Currently available Rocky Mountain spotted fever (RMSF) vaccines are relatively ineffective in preventing infections in humans and contain considerable amounts of contaminating egg protein. A new formalin-inactivated vaccine was prepared by sucrose density gradient centrifugation of the Sheila Smith strain of Rickettsia rickettsii grown in chick embryo cell tissue culture. The new product has greater protective immunogenicity in rheusus monkeys and guinea pigs than commercial vaccines. Six volunteers without immunologic evidence of prior exposure to RMSF received from one to three inoculations of the vaccine diluted 1:10, and there were two benign local reactions. Titers of antibody (determined by microagglutination and indirect fluorescence techniques) increased in all recipients as did lymphocyte tranformation responses to specific rickettsial antigen. Ten volunteers were immunized twice with vaccine diluted 1:3; there were no local reactions, and immunologic responses were similar to those in the six volunteers in the first group. The proper dosage and immunization schedule for the vaccine must be determined in further studies.
目前可用的落基山斑疹热（RMSF）疫苗在预防人类感染方面相对无效，并且含有大量污染性卵蛋白。一种新的福尔马林灭活疫苗是通过对在鸡胚细胞组织培养中生长的立氏立克次体希拉·史密斯菌株进行蔗糖密度梯度离心制备的。该新产品在恒河猴和豚鼠中比商业疫苗具有更强的保护性免疫原性。六名无先前接触RMSF免疫证据的志愿者接受了1至3次1:10稀释疫苗的接种，出现了两例良性局部反应。所有接受者的抗体滴度（通过微量凝集和间接荧光技术测定）均升高，对特异性立克次体抗原的淋巴细胞转化反应也升高。十名志愿者用1:3稀释的疫苗免疫两次；未出现局部反应，免疫反应与第一组的六名志愿者相似。疫苗的合适剂量和免疫程序必须在进一步研究中确定。
