抄録
A strain which is sensitive to the antibodies and insensitive to the non-specific inhibitor in human serum.
16 strains of influenza virus were isolated in Kyushu district 1959 and classified into P, Q phase virus.
There was one strain among them which was sensitive to the antibody of human convalescent serum and insensitive to the non-specific inhibitor in human and horse serum and it was studied principally.
The results were as follows.
1) 16 strains isolated from the outbreak in Kyushu district 1959 were identified as Asian type influenza virus, and 15 isolated strains were P-phase and 1 strain was X-phase.
2) The distribution of P-Q phase virus isolated in Kyushu district from 1957 to 1959 was irregular at each epidemic, but increase of P-phase virus and decrease of Q and X-phase virus were recognized.
3) Haemagglutination of Kumamoto KB-4-59 (X-phase) was inhibited by normal horse serum and HAT titres were irregular at each generation and dilution of inocula but when we subcultured this strain mixing with diluted horse serum (1:100), it became to be not inhibited by normal human and horse serum, and its character was stable until E-13 (13 egg passages).
4) The change of antigenic structure of KB-4 (subcultured with horse serum) was not observed.
5) As KB-4 was not inhibited by inhibitor in human serum, HAT antibody in human serum could be investigated without treatment of the serum with IRE and Sodium periodate.
6) P-Q phase virus were not closely related with cow red cell agglutination.
7) The sensitivity to specific antibodies and inhibitores was not related with CF antigen titre.
8) P-phase virus had the highest immunogenicity of the 3 phase viruses and X-phase virus had higher one than Q-phase virus, when mice were immunized with 3 viruses.
