Newcastle Disease Virusの免疫に関する研究 第2編 感染動物臓器よりつくつたNewcastle virus vaccineの抗原性に就て

Although there are many investigations about the effects of various antigens of the Newcastle disease virus, the author makes reports on the antigenicity of this virus and also on the immune effects of various fractions obtained on the way of purification of the used materials. The materials chosen for this research were the fowl brains and chick-embryos infected with this virus. 1) In the case where the tissue emulsion was chosen as vaccine, the emulsized tissue as it was had very remarkable effect. 2) Whether formal dehyde or merzonin may be used for inactivation, the immune effect remained to the same degree. 3) The condensation of chorioallantoic fluid to one-fifth of it by Brumfield's methanol sedimentation method, showed great loss of antigenicity, having the hemagglutination and infectious titers of only one-second of those of the original chorioallantoic fluid. 4) The purified and non-purified antigens of the infected chorioallantoic fluid and of 10% emulsions of the fowl brains and chick-embyros were inoculated into the hearts of chickens. Then the purified antigen of chorioallantoic fluid and non-purified antigen of emulsized chick-embryos showed better results than the others, in all of the tests of sen sitized cell agglutination, hemagglutination and of protection against infection. 5) The Newcastle disease virus had its kaolin-adsorption and -dissociation points at pH 4.0 and 8.0 respectively, and the adsorption on kaolin was well performed by repeating it twice. 6) Studying the nitrogen quantity and infectious titer of the kaolin-adsorption and -dissociation products of 10% fowl brain emulsions, the supernatant of adsorption was rich in tissue components and poor in viruses, but that of dissociation was rich in viruses and poor in tissue components. 7) The portion, which is rich in tissue elements and poor in viruses, showed greater antigenicity than the other portion, when they were inactivated and inoculated into chick-hearts. Considering the above-mentioned results, the emulsized chick-embryos as these are seem to be the best one as the antigen of Newcastle disease virus, in view of the intensity of the antigenicity, and the possibility of intramuscular injection and mass production.