AIM： To analyze the biological role of the surface antigen of Toxoplasma gondii（Tgondii） in development of vaccine. METHODS： The surface antigen of Tgondii （SAG1） was expressed in vitro. The immune response of t...AIM： To analyze the biological role of the surface antigen of Toxoplasma gondii（Tgondii） in development of vaccine. METHODS： The surface antigen of Tgondii （SAG1） was expressed in vitro. The immune response of the host to the antigen was investigated by detection of specific antibody reaction to SAG1 and production of cytokines. Mice were immunized with recombinant SAG1 and challenged with lethal strain of Tgondii RH. The monoclonal antibody to r-SAG1 was prepared and used to study the effects of SAG1 on Tgondii tachyzoites under electromicroscope. RESULTS： The mice immunized with recombinant SAG1 delayed death for 60 h compared to the control group. The recombinant SAG1 induced specific high titer of IgG and IgM antibodies as well as IFN-y, IL-2 and IL-4 cytokines in mice. In contrast, IL-12, IL-6 and TNF-α were undetectable. When T gondii tachyzoites were treated with the monoclonal antibody to r-SAG1, the parasites were gathered together, destroyed, deformed, swollen, and holes and gaps formed on the surface. CONCLUSION： SAG1 may be an excellent vaccine candidate against T gondii. The immune protection induced by SAG1 against Tgondii may be regulated by both hormone- and cell-mediated immune response.展开更多
Haustorium formation is the characteristic feature of all parasitic plants and a vital process for successful parasitism.Previous investigations on haustorium initiation and development are constricted to induced proc...Haustorium formation is the characteristic feature of all parasitic plants and a vital process for successful parasitism.Previous investigations on haustorium initiation and development are constricted to induced processes by host-derived signals or synthetic analogs.Spontaneous haustorium formation in the absence of host signals,a process representing an early stage in the evolution of parasitic plants,remains largely unexplored.Lack of fast and frequent formation of spontaneous haustoria greatly hinders full understanding of haustorium formation in root hemiparasites.In this study,seedlings of Pedicularis kansuensis Maxim.,a facultative root hemiparasitic species in Orobanchaceae observed to produce many spontaneous haustoria,were grown in autoclaved water agar in the absence of any known haustoriuminducing stimulants.We aimed to test the temporal and developmental pattern of spontaneous haustorium formation.Also,effects of sucrose supply and root contact on spontaneous haustorium formation were tested.Spontaneous haustoria were observed starting from six days after germination,much earlier than previously reported root hemiparasites.A majority of the spontaneous haustoria formed on lateral roots.Percentage of seedlings with spontaneous haustoria was 28.8% when grown on water agar plates,with a mean of four haustoria per seedling two weeks after germination.Haustorium formation by seedlings grown in water agar amended with 2% sucrose was more than twice of those without sucrose amendment.Singly grown seedlings were able to develop spontaneous haustoria at similar levels as those grown with another conspecific seedling.In view of the fast and abundant formation of spontaneous haustoria,P.kansuensis may be developed as an excellent experimental system in future investigations for unraveling endogenous regulation of haustorium initiation and development in root hemiparasitic plants.展开更多
Potato is the main material of nutrition comes after the wheat and, is subjected to attacks of different plant parasitic nematodes which cause serious damages in our country. Especially, root-knot nematodes cause seri...Potato is the main material of nutrition comes after the wheat and, is subjected to attacks of different plant parasitic nematodes which cause serious damages in our country. Especially, root-knot nematodes cause serious crop losses on them. Due to usage oflnfested seeds, parasitic nematodes are increasing from year to year. In our country, so far, many infested hosts of Meloidogyne incognita （Kofoid ＆White, 1919） Chitwood, 1949 were detected but there is no report on investigation on potato. During this study, adult females of root-knot nematodes were obtained via extracting gals of 133 tuber samples, collected potatoes fields in the Marmara region especially Balikesir, Bilecik, Bursa, Canakkale, Edirne, Istanbul, Kirklareli, Kocaeli, Sakarya and Tekirdag provinces during 2007-2008. During identification the species, second stage larvae were taken into consideration as well as genital preparations of adult females. For the identification classical methods were used together with molecular methods. As result, M. incognita was detected, only species detected among the Meloidogyne genus upon the 10 provinces investigated in Edirne province, Bosna village. This is the first report of the infestation of this species potato and also in Marmara Region.展开更多
基金Supported by China Ministry of Human Affairs and Department of Science and Technology of Shandong Province, No. 031050115
文摘AIM： To analyze the biological role of the surface antigen of Toxoplasma gondii（Tgondii） in development of vaccine. METHODS： The surface antigen of Tgondii （SAG1） was expressed in vitro. The immune response of the host to the antigen was investigated by detection of specific antibody reaction to SAG1 and production of cytokines. Mice were immunized with recombinant SAG1 and challenged with lethal strain of Tgondii RH. The monoclonal antibody to r-SAG1 was prepared and used to study the effects of SAG1 on Tgondii tachyzoites under electromicroscope. RESULTS： The mice immunized with recombinant SAG1 delayed death for 60 h compared to the control group. The recombinant SAG1 induced specific high titer of IgG and IgM antibodies as well as IFN-y, IL-2 and IL-4 cytokines in mice. In contrast, IL-12, IL-6 and TNF-α were undetectable. When T gondii tachyzoites were treated with the monoclonal antibody to r-SAG1, the parasites were gathered together, destroyed, deformed, swollen, and holes and gaps formed on the surface. CONCLUSION： SAG1 may be an excellent vaccine candidate against T gondii. The immune protection induced by SAG1 against Tgondii may be regulated by both hormone- and cell-mediated immune response.
基金financially supported by the Natural Science Foundation of China(31370512,U1303201,and 31400440)Natural Science Foundation of Yunnan Province(2016FB059)+1 种基金funding for Airong Li from The Youth Innovation Promotion Association of Chinese Academy of Sciencesthe Young Academic and Technical Leader Raising Foundation of Yunnan Province(2014HB047)
文摘Haustorium formation is the characteristic feature of all parasitic plants and a vital process for successful parasitism.Previous investigations on haustorium initiation and development are constricted to induced processes by host-derived signals or synthetic analogs.Spontaneous haustorium formation in the absence of host signals,a process representing an early stage in the evolution of parasitic plants,remains largely unexplored.Lack of fast and frequent formation of spontaneous haustoria greatly hinders full understanding of haustorium formation in root hemiparasites.In this study,seedlings of Pedicularis kansuensis Maxim.,a facultative root hemiparasitic species in Orobanchaceae observed to produce many spontaneous haustoria,were grown in autoclaved water agar in the absence of any known haustoriuminducing stimulants.We aimed to test the temporal and developmental pattern of spontaneous haustorium formation.Also,effects of sucrose supply and root contact on spontaneous haustorium formation were tested.Spontaneous haustoria were observed starting from six days after germination,much earlier than previously reported root hemiparasites.A majority of the spontaneous haustoria formed on lateral roots.Percentage of seedlings with spontaneous haustoria was 28.8% when grown on water agar plates,with a mean of four haustoria per seedling two weeks after germination.Haustorium formation by seedlings grown in water agar amended with 2% sucrose was more than twice of those without sucrose amendment.Singly grown seedlings were able to develop spontaneous haustoria at similar levels as those grown with another conspecific seedling.In view of the fast and abundant formation of spontaneous haustoria,P.kansuensis may be developed as an excellent experimental system in future investigations for unraveling endogenous regulation of haustorium initiation and development in root hemiparasitic plants.
文摘Potato is the main material of nutrition comes after the wheat and, is subjected to attacks of different plant parasitic nematodes which cause serious damages in our country. Especially, root-knot nematodes cause serious crop losses on them. Due to usage oflnfested seeds, parasitic nematodes are increasing from year to year. In our country, so far, many infested hosts of Meloidogyne incognita （Kofoid ＆White, 1919） Chitwood, 1949 were detected but there is no report on investigation on potato. During this study, adult females of root-knot nematodes were obtained via extracting gals of 133 tuber samples, collected potatoes fields in the Marmara region especially Balikesir, Bilecik, Bursa, Canakkale, Edirne, Istanbul, Kirklareli, Kocaeli, Sakarya and Tekirdag provinces during 2007-2008. During identification the species, second stage larvae were taken into consideration as well as genital preparations of adult females. For the identification classical methods were used together with molecular methods. As result, M. incognita was detected, only species detected among the Meloidogyne genus upon the 10 provinces investigated in Edirne province, Bosna village. This is the first report of the infestation of this species potato and also in Marmara Region.
