日本腦炎ワクチンの研究に関連して調べられたマウス腦と鷄胎兒との比較

Abstract

Between mouse brain (MB) and 12-day-old chick embryo body (CE) tissue, as materials for the preparation of JAPANESE ENCEPHALITIS vaccine, several differences were found:1) Total Nitrogen content of MB tissue was 2.3 times while the supernate of MB centrifuged at 2500r.p.m. for 15 minutes contained 1.2 times as much Nitrogen, 2) total solids of MB was 2.6 times, 3) mouse intracerebral titers of infected MB tissue were from 6.3 to 200 times, 4) and calculated mouse i. c. LD 50 per mg Nitrogen of MB supernate was from 5, 4 to 170 times, all the above mentioned, approximately, as compared with those of CE tissue. 5) In the cross complement fixation tests using MB and CE antigens with the corresponding immune guinea pig sera, the reaction in homologous relation were stronger than in heterologous relation. 6) Any significant differences in neutralization indices could not be found in cross neutralization test using the same immune guinea pig sera as in c. f. test, and the corresponding both viruses. 7) In cross immunization tests in mice which were vaccinated with MB and CE vaccine and challenged with both viruses, the protection in homologous relation was not necessarily stronger than that in heterologous relation. 8) The protective power of CE vaccine was disproportionnally weaker than that of MB vaccine on the basis of infective titer before inactivation of vaccine. 9) The heated infected mouse brain suspension have a tendency of lowering LD50 titer when added to MB or CE virus in infectivity titration. The same was not observed in the heated CE suspension. This inhibiting effect on virus seems to be partly nonspecific.