Pisiformis oncosphere

Early studies with T. taeniaeformis in mice (Miller and Gardiner, 1932 Campbell, 1938b Leid and Williams, 1974 Musoke et al., 1975 Mitchell et al., 1977, 1980), T. pisiformis in rabbits (Campbell, 1938a), T. saginata in cattle (Lloyd and Soulsby, 1976) and T. ovis in sheep (Blundell et al., 1968 Rickard et al., 1977 Heath et al., 1979 Harrison et al., 1993) demonstrated that antibodies in the sera of infected or immunized hosts were capable of transferring passive immunity to na ive hosts. The presence and activities of these protective antibodies were found to be evident in vitro through the demonstration that activated oncospheres were killed if cultured in the presence of serum from infected or vaccinated... 

Rajasekariah, G.R., Rickard, M.D. and O Donnell, I.J. (1985) Taenia pisiformis protective immunization of rabbits with solubilized oncospheral antigens. Experimental Parasitology 59, 321-327. 

Fig. 8.22. Jejunal villi of ruminant and non-ruminant showing paths followed by oncospheres of Echinococcus granulosus and Taenia pisiformis (and some other Taenia spp.). The larger diameter of the E. granulosus oncosphere probably enables it to reach the lymphatic before being translocated in a venule. (Reprinted with permission from International Journal of Parasitology, 1, Heath, D. D., The migration of oncospheres of Taenia pisiformis, T. serialis and Echinococcus granulosus within the intermediate host, 1971, Pergamon Journals Ltd.)...

The most successful species cultured to date has been T. pisiformis, using essentially the technique used for E. granulosus (610, 801). Although sexually mature adults with proglottides were obtained, these did not contain infective oncospheres. 

The following species of Taenia have been grown from oncospheres to active larvae with suckers T. hydatigena, T. ovis, T. pisiformis, T. serialis and E. granulosus (308, 314). The techniques of Heath Smyth (314), or modifications of them, have been used widely by other workers for the production and collection of E/S antigens of oncospheres in the preparation of potential vaccines (see Chapter 11, p. 302). Only limited success has been achieved with the culture of larval T. saginata (310, 471) and almost none with T. solium, and the in vitro culture of these important species remains a challenge. 

Barker, I. K. (1970). The penetration of oncospheres of Taenia pisiformis into the intestine of the rabbit. Canadian Journal of Zoology, 48 1329-32. 

Heath, D. D. (1971). The migration of the oncospheres of Taenia pisiformis, T. serialis, and Echinococcus granulosus within the intermediate host. International Journal for Parasitology, 1 145-52. 

Heath, D. D. Smyth, J. D. (1970). In vitro culture of Echinococcus granulosus, Taenia hydatigena, T. ovis, T. pisiformis and T. serialis from oncosphere to cystic larva. Parasitology, 61 329-43. 

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