AUTHOR=Shi Tuanyuan , Tao Geru , Bao Guolian , Suo Jingxia , Hao Lili , Fu Yuan , Suo Xun 

TITLE=Stable Transfection of Eimeria intestinalis and Investigation of Its Life Cycle, Reproduction and Immunogenicity

JOURNAL=Frontiers in Microbiology

VOLUME=7

YEAR=2016

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2016.00807

DOI=10.3389/fmicb.2016.00807

ISSN=1664-302X

ABSTRACT=<p>Rabbit coccidiosis, caused by infection of <italic>Eimeria</italic> spp. is one of the most severe parasitic diseases in rabbits. <italic>Eimeria intestinalis</italic> is one of the most immunogenic species in rabbit coccidia. Due to the lack of genomic information and unsuccessful <italic>in vitro</italic> cultivation, genetic manipulation of rabbit coccidia lagged behind other apicomplexan parasites. Using regulatory sequences from <italic>E. tenella</italic>, we obtained a transgenic line of <italic>E. intestinalis</italic> expressing yellow fluorescent protein (YFP). YFP was continuously expressed throughout the whole life cycle. Morphological features of <italic>E. intestinalis</italic> in different developmental stages were dynamically observed with the transgenic line. Some important features in the endogenous development stages were observed. Trophozoites were found as early as 4 h post inoculation. Two types of schizonts and merozoites were observed in first three of the four schizogonies. Beside jejunum and ileum, gametogony stage and oocysts were also found in the duodenum and vermiform appendix. In addition, the transgenic strain was highly immunogenic but less pathogenic than the wild type. Considering the high immunogenicity of <italic>E. intestinalis</italic> and amenability to transfection with foreign genes, transgenic <italic>E. intestinalis</italic> could be a promising oral eukaryotic vaccine vector.</p>