| 8． |
Experimental infection of dogs with Babesia microti.
Ohmori, T., Uetsuka, K. and Nunoya, T.
Nippon Institute for Biological Science
Journal of Protozoology Research 21:78-84, 2011
Abstract: To know the infectivity of Babesia microti parasites in dogs, two dogs were experimentally inoculated with B. microti and parasitemia levels were monitored. Number of erythrocytes gradually decreased until 32 days after the inoculation and then recovered to normal levels thereafter. Parasites in the erythrocytes were first observed at 35 days after the inoculation and parasitemia levels reached approximately 1% around 50 days after inoculation in 2 dogs. Infected dogs showed transiently decreased number of erythrocytes but no clinical signs during the experimental periods. Smears of the parasitized dog erythrocytes showed positive reaction with anti-B. microti serum. The PCR assay in parasites DNA from the dogs showed the amplification of B. microti marker gene and the sequence showed 99% homology with the 16S-like small subunits from B. microti. These findings show the replication of B. microti in dogs and suggest the possibility that B. microti is a source of canine babesiosis if the parasite can be transmitted by ticks.
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| 19． |
粘膜ワクチンinワクチン 最新動向と展望．
竹山夏実1,2)、幸義和2)、清野宏2)
1)日本生物科学研究所、2)東京大学医科学研究所
日本臨床 69巻：1555‐1560、2011年
Abtstact: Mucosal vaccination has several advantages compared with that of injection-type vaccination. Secretory IgA (SIgA) produced at mucosal surface plays a key role for inactivation of toxins and inhibition of pathogen invasion. Although oral or nasal vaccination with attenuated live microorganisms has been shown to be effective in the induction of protective immunity, these types of vaccine have the ability to infect transiently to the host. For the development of safe and effective mucosal vaccine, an obvious strategy is the preparation of inactivated subunit-type mucosal vaccine. Here we introduce our frontier technology for the development of rice based oral vaccines, as a new generation of mucosal vaccine. Further, we also discuss recent progress in the development of other types of mucosal vaccine and adjuvant. |
| 20． |
動物用ワクチンの変遷と感染症の制圧・排除･根絶‐日本の牛疫ワクチンと狂犬病ワクチンを中心に‐．
土屋耕太郎
日本生物科学研究所
日本獣医史学雑誌 49号：10‐21、2012年
Abstract: OIE declared at 25 May 2011 that rinderpest is eradicated from the surface of the earth. Modern measure for the struggling against rinderpest had begun with a production of a large quantity of immune serum in cattle and injection of it to naïve cattle. Cattle were refractory to rinderpest for less than 1 month by the measure. The first rinderpest vaccine, Kakizaki vaccine (1917), prevented rinderpest and extended immune status of cattle up to half a year. Although the vaccine produced from a head of cattle was only for 50 heads of cattle, it was used to 250,000 heads of cattle for 8 years. The development of live lapinized Nakamura III vaccine (L vaccine) vastly improved the immunogenicity of rinderpest vaccine to induce refractory period of 2 to 3 years or more in vaccinated cattle. The vaccine was highly effective and widely used in Asia and Africa to eliminate rinderpest. Residual pathogenicity of the L vaccine to some cattle breed has been modified by avinization of L strain. The developed LA (lapinized and avinized) vaccine is no more pathogenic even if to the highly sensitive cattle breed. Afterwards, cost-effective tissue-culture-derived live vaccine has been developed, and used for the rinderpest eradication programme conducted by FAO with OIE pathway. Another Japanese story, rabies vaccines in Japan started with infectivity-reduced vaccines. Around 1920, the vaccines were started to be used for the immunization of dogs for the first time in the world to control urban rabies. After World War 2, the vaccines were exchanged by inactivated Semple-type vaccine, and now tissue-culture-derived inactivated vaccine has been developed and used in Japan. Rabies prevention law in Japan has been enforced in 1950. The law set down the registration and vaccination of domestic dogs, detention of unregistered and unvaccinated dogs, and import and export animal quarantine. Under this system, number of rabies cases in Japan declined to establish one of the few rabies-free countries for more than 50 years. These two stories show us that gradual improvements of vaccines provide us the more effective and safer ones, and the thoughtful strategies for the usage of the vaccines leads to control, elimination, and ultimately eradication of infectious diseases.
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