1990 Fiscal Year Final Research Report Summary
Immunology and Molecular Biology of Cestode Infections.
| Project/Area Number |
63480168
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
Immunology
|
|---|
| Research Institution | Yamagata University |
|---|
Principal Investigator |
ONITAKE Kazuo Yamagat University Biology Associate Professor, 理学部, 助教授 (80089846)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
ITO Akira Gifu University Parasitology Assistant Professor, 医学部, 講師 (70054020)
|
|---|
| Project Period (FY) |
1988 – 1990
|
| Keywords | Cestode Infections / Hymenolepididae / Taeniidae / Mouse / Rat / Oncospheral Antigens / Cross Immunity / Recombinant Vaccine |
|---|
| Research Abstract |
The host-parasite interaction in cestode infections has been analyzed using several species of cestodes, Hvmenolepis spp. and Taenia taeniaeformis in mice and rats. At least two different species are required as the intermediate and definitive hosts for completion of the life-cycle of cestodes except H. nana. In the present work, we have analyzed (1) immunogenicity of adult cestodes in the intestinal lumen of deinitive host with emphasis on the fate of cncospheres produced by and released from mature adult worms, and (2) that of larval cestodes in the tissue of the intermediate host with emphasis on the host-protective antigens of the oncosphere. In the former, it has become clear that (1) adult cestodes are immunogenic but the immunogenicity differs from that of larval cestodes, (2) immunity to larval cestodes or adult cestodes is stage-specific but not always species-specific. On the life cycle of cestodes, we have found tht oncosphere embryos produced by and released from adult csto
… More
des of H. microstoma and H. diminuta, which require beetles as the intermediate host, may hatch and invade the intestinal tissue of the definitive host. Although it is open to question whether oncospheres invaded the tissue of the definitive host could develop into larval cstodes, this observation provides a good explanation as to why mice experienced patent infecion with H. microstoma produce anti-oncosphere antibodies in addition to anti-larval and anti-oncosphere antibodies and why mice given viable eggs of this parasite produce anti-oncosphere antibodies exclusively and show strong resistance to challenge infection with oncospheres of H. nana. At present, we may speculate the reason why anti-oncosphere antibodies are produced in the definitive host dogs infected with Echinocococcus granulosus or E, multilocularis of medical importance. In the latter, we have shown the importance of oncospheres as the immunogen in mammalian intermediate hosts. With collaboration with Australian scientists, we have succeeded in establishing Escherichia coli producing oncosphere stage-specific and host-protective polypeptide of 21 kDa. This is the first demonstrating oncosphere stage-specific component produced by recombinant DNA technology. Less
|
