Immunization with Toxoplasma gondii GRA17 deletion mutant induces partial protection and survival in challenged mice

Toxoplasmosis remains a world-threatening disease largely because of the lack of a fully effective vaccine. Here, we created a ΔGRA17 mutant by disrupting the virulence factor GRA17 using CRISPR-Cas9 method. Then, we tested whether ΔGRA17 tachyzoites can be used as a live-attenuated vaccine against...

Full description

Bibliographic Details
Main Authors: Wang, Jin-Lei, Elsheikha, Hany M., Zhu, Wei-Ning, Chen, Kai, Li, Ting-Ting, Yue, Dong-Mei, Zhang, Xiao-Xuan, Huang, Si-Yang, Zhu, Xing-Quan
Format: Article
Published: Frontiers Media 2017
Subjects:
Online Access:https://eprints.nottingham.ac.uk/43930/
_version_ 1848796799156879360
author Wang, Jin-Lei
Elsheikha, Hany M.
Zhu, Wei-Ning
Chen, Kai
Li, Ting-Ting
Yue, Dong-Mei
Zhang, Xiao-Xuan
Huang, Si-Yang
Zhu, Xing-Quan
author_facet Wang, Jin-Lei
Elsheikha, Hany M.
Zhu, Wei-Ning
Chen, Kai
Li, Ting-Ting
Yue, Dong-Mei
Zhang, Xiao-Xuan
Huang, Si-Yang
Zhu, Xing-Quan
author_sort Wang, Jin-Lei
building Nottingham Research Data Repository
collection Online Access
description Toxoplasmosis remains a world-threatening disease largely because of the lack of a fully effective vaccine. Here, we created a ΔGRA17 mutant by disrupting the virulence factor GRA17 using CRISPR-Cas9 method. Then, we tested whether ΔGRA17 tachyzoites can be used as a live-attenuated vaccine against acute, chronic, and congenital Toxoplasma gondii infection in mice. Immune response evoked by ΔGRA17 immunization suggested a sequential Th1 and Th2 T cell response, indicated by high levels of Th1 and a mixed Th1/Th2 cytokines at 28 and 70 days after immunization, respectively. ΔGRA17-mediated immunity fully protected mice against lethal infection with wild-type (wt) RH strain, heterologous challenge with PYS, and TgC7 strains of the Chinese ToxoDB#9 genotype, and T. gondii Pru strain. Although parasite cysts were detected in 8 out of 10 immunized mice, cyst burden in the brain was significantly reduced (P < 0.05) in immunized mice (53 ± 15 cysts/brain) compared to non-immunized mice (4,296 ± 687 cysts/brain). In respect to congenital infection, the litter size, survival rate, and body weight (BW) of pups born to ΔGRA17-immunized dams were not different compared to pups born to naïve control dams (P = 0.24). However, a marked reduction in the litter size (P < 0.001), survival rate, and BW (P < 0.01) of pups born to non-immunized and infected dams was detected. Also, immunized dams infected with type II Pru strain had significantly (P < 0.001) less cyst burden in the brain compared with non-immunized and infected dams. These findings show that immunization with ΔGRA17 strain evokes cell-mediated and neutralizing antibody responses and confers some degree of protection against challenge with homologous and heterologous virulent T. gondii strains.
first_indexed 2025-11-14T19:53:43Z
format Article
id nottingham-43930
institution University of Nottingham Malaysia Campus
institution_category Local University
last_indexed 2025-11-14T19:53:43Z
publishDate 2017
publisher Frontiers Media
recordtype eprints
repository_type Digital Repository
spelling nottingham-439302020-05-04T18:52:11Z https://eprints.nottingham.ac.uk/43930/ Immunization with Toxoplasma gondii GRA17 deletion mutant induces partial protection and survival in challenged mice Wang, Jin-Lei Elsheikha, Hany M. Zhu, Wei-Ning Chen, Kai Li, Ting-Ting Yue, Dong-Mei Zhang, Xiao-Xuan Huang, Si-Yang Zhu, Xing-Quan Toxoplasmosis remains a world-threatening disease largely because of the lack of a fully effective vaccine. Here, we created a ΔGRA17 mutant by disrupting the virulence factor GRA17 using CRISPR-Cas9 method. Then, we tested whether ΔGRA17 tachyzoites can be used as a live-attenuated vaccine against acute, chronic, and congenital Toxoplasma gondii infection in mice. Immune response evoked by ΔGRA17 immunization suggested a sequential Th1 and Th2 T cell response, indicated by high levels of Th1 and a mixed Th1/Th2 cytokines at 28 and 70 days after immunization, respectively. ΔGRA17-mediated immunity fully protected mice against lethal infection with wild-type (wt) RH strain, heterologous challenge with PYS, and TgC7 strains of the Chinese ToxoDB#9 genotype, and T. gondii Pru strain. Although parasite cysts were detected in 8 out of 10 immunized mice, cyst burden in the brain was significantly reduced (P < 0.05) in immunized mice (53 ± 15 cysts/brain) compared to non-immunized mice (4,296 ± 687 cysts/brain). In respect to congenital infection, the litter size, survival rate, and body weight (BW) of pups born to ΔGRA17-immunized dams were not different compared to pups born to naïve control dams (P = 0.24). However, a marked reduction in the litter size (P < 0.001), survival rate, and BW (P < 0.01) of pups born to non-immunized and infected dams was detected. Also, immunized dams infected with type II Pru strain had significantly (P < 0.001) less cyst burden in the brain compared with non-immunized and infected dams. These findings show that immunization with ΔGRA17 strain evokes cell-mediated and neutralizing antibody responses and confers some degree of protection against challenge with homologous and heterologous virulent T. gondii strains. Frontiers Media 2017-06-29 Article PeerReviewed Wang, Jin-Lei, Elsheikha, Hany M., Zhu, Wei-Ning, Chen, Kai, Li, Ting-Ting, Yue, Dong-Mei, Zhang, Xiao-Xuan, Huang, Si-Yang and Zhu, Xing-Quan (2017) Immunization with Toxoplasma gondii GRA17 deletion mutant induces partial protection and survival in challenged mice. Frontiers in Immunology, 8 . ISSN 1664-3224 Toxoplasma gondii immunization live-attenuated vaccine ΔGRA17 Th1/Th2 cytokines http://journal.frontiersin.org/article/10.3389/fimmu.2017.00730/full doi:10.3389/fimmu.2017.00730 doi:10.3389/fimmu.2017.00730
spellingShingle Toxoplasma gondii
immunization
live-attenuated vaccine
ΔGRA17
Th1/Th2 cytokines
Wang, Jin-Lei
Elsheikha, Hany M.
Zhu, Wei-Ning
Chen, Kai
Li, Ting-Ting
Yue, Dong-Mei
Zhang, Xiao-Xuan
Huang, Si-Yang
Zhu, Xing-Quan
Immunization with Toxoplasma gondii GRA17 deletion mutant induces partial protection and survival in challenged mice
title Immunization with Toxoplasma gondii GRA17 deletion mutant induces partial protection and survival in challenged mice
title_full Immunization with Toxoplasma gondii GRA17 deletion mutant induces partial protection and survival in challenged mice
title_fullStr Immunization with Toxoplasma gondii GRA17 deletion mutant induces partial protection and survival in challenged mice
title_full_unstemmed Immunization with Toxoplasma gondii GRA17 deletion mutant induces partial protection and survival in challenged mice
title_short Immunization with Toxoplasma gondii GRA17 deletion mutant induces partial protection and survival in challenged mice
title_sort immunization with toxoplasma gondii gra17 deletion mutant induces partial protection and survival in challenged mice
topic Toxoplasma gondii
immunization
live-attenuated vaccine
ΔGRA17
Th1/Th2 cytokines
url https://eprints.nottingham.ac.uk/43930/
https://eprints.nottingham.ac.uk/43930/
https://eprints.nottingham.ac.uk/43930/