流行性乙型脑炎猪肾组织培养疫苗的研究 Ⅰ.病毒的培养和疫苗的制备

STUDIES ON THE SWINE KIDNEY TISSUE CULTURE VACCINE OF JAPANESE B ENCEPHALITIS Ⅰ.MULTIPLICATION OF VIRUS AND PREPARATION OF VACCINE

为了改进流行性乙型脑炎疫苗的质量,在国内曾进行了乙醚提纯脑炎疫苗,白陶土和硫酸铵提纯病毒及疫苗以及鸡胚组织培养疫苗的研究。我系曾证明以流行性乙型脑炎病毒感染猪后能引起毒血症,其病毒滴度可达10-3.5。因此,在1958年我们开始用猪肾单层细胞来培养流行性乙型脑炎病毒,并进行了猪肾组织培养疫苗的研究。应用这种方法有可能制备出一种安全。

Because of the presence of nervous tissue in the mouse brain vaccine which mightgive rise to unfavourable reaction, swine kidney monolayer cell tissue culture for the pre-paration of virus and preparation of vaccine was investigated. The Japanese B encephalitis virus multiplies intensively in the swine kidney cells,reaching a titer of 10-5.50 to 10-6.50 (LD50 in mice per 0.03ml intracerebrally) at the 3rdor 4th day after inoculation, and the 4th day was the time chosen for the harvest ofvirus and preparation of vaccine. The virus multiplies not only in the 199 synthetic medium, but also in Rappa-port’s medium, cysteine-isoleucine-ribose medium or cystine medium alone. The virustiter attained from 10-5.0 to 10-6.50. Inoculation of different concentrations of mouse brain virus suspension (10-1, 10-3,10-5) into swine kidney tissue culture, the maximal virus titer attained almost the samelevel, but the peak of the virus titer reached at the 2nd, 4th, and 5th day respectively.The 50% minimal immunogenic dose in the 22 tested vaccines showed that 59.1%of the vaccine had passed the criterion of 0.01ml （according to the modification ofSabin’s mouse brain vaccine method）. The immunogenic indices after immunization ofthe total intraperitoneal dose of 0.1ml of the tissue culture vaccine to mice, vary from51,920 to 3,613,000 in different lots of vaccine. Effective vaccine can also be prepared with Rappaport’s medium, cysteine-isoleuine-ribose medium or cysteine medium alone. Using a concentration of 1:1000 formalin for the inactivation of virus, the potencyof most lots of vaccines decreased obviously after storage in the refrigerator for about4 months.