Development ofEimeria nieschulzi(Coccidia, Apicomplexa) Gamonts and Oocysts in Primary Fetal Rat Cells

Abstract

The in vitro production of gametocytes and oocysts of the apicomplexan parasite genus Eimeria is still a challenge in coccidiosis research. Until today, an in vitro development of gametocytes or oocysts had only been shown in some Eimeria species. For several mammalian Eimeria species, partial developments could be achieved in different cell types, but a development up to gametocytes or oocysts is still lacking. This study compares several permanent cell lines with primary fetal cells of the black rat (Rattus norvegicus) concerning the qualitative in vitro development of the rat parasite Eimeria nieschulzi. With the help of transgenic parasites, the developmental progress was documented. The selected Eimeria nieschulzi strain constitutively expresses the yellow fluorescent protein and a macrogamont specific upregulated red tandem dimer tomato. In the majority of all investigated host cells the development stopped at the second merozoite stage. In a mixed culture of cells derived from inner fetal organs the development of schizont generations I-IV, macrogamonts, and oocysts were observed in crypt-like organoid structures. Microgamonts and microgametes could not be observed and oocysts did not sporulate under air supply. By immunohistology, we could confirm that wild-type E. nieschulzi stages can be found in the crypts of the small intestine. The results of this study may be helpful for characterization of native host cells and for development of an in vitro cultivation system for Eimeria species.

Distribution and Processing of Eimeria nieschulziOWP13, a New Protein of the COWP Family

“…The investigation of enzymes was not in the focus of this study, but the FITC-cadaverine staining supports the assumption after analyzing the amino acid sequence of EnOWP13. Transglutaminase inhibitors, like cystamine, could shed more light in the role of transglutaminase activity in the wall formation process, but the in vitro growth of E. nieschulzi gamonts is complex and a reliable cultivation of small intestinal organoids from rats has not been described yet (Chen et al 2013). In gamont stage-specific transcript data of Eimeria, no transglutaminase is annotated yet, but a C2 domain-containing protein with a transglut-core unit (Gene ID ETH_00002295) can be found.…”

Transfection of Eimeria mitis with Yellow Fluorescent Protein as Reporter and the Endogenous Development of the Transgenic Parasite

“…Eimeria mitis , one of the seven species of chicken coccidia, was first described by Tyzzer in 1929 [17] and considered to be relatively less pathogenic [18] – [21] . Successful genetic complementation of other Eimeria species including Eimeria acervulina , Eimeria maxima , and Eimeria praecox , as well as the rat-specific Eimeria nieschulzi [22] – [24] , support the potential use of less pathogenic species as vectors to develop novel vaccines [4] . Additionally, different intestinal localizations of the seven Eimeria species that infect chickens may have great implications in the performance of various Eimeria species as vaccine vector.…”

Establishment of an in vitro chicken epithelial cell line model to investigate Eimeria tenella gamete development

“…E. bovis , E. ovinoidalis , E. ninakohlyakimovae ) have shown that the parasite can develop to various stages (merozoites I and a few gametocyte-like stages) in several cell types, including bovine, human and porcine endothelial cell lines, bovine foetal gastrointestinal cells, bovine kidney epithelial cells and African green monkey kidney epithelial cells [ 28 – 32 ]. More particularly, the development of E. nieschulzi macrogamonts and oocysts were observed when cultured with mixed cells derived from inner fetal organs [ 32 ]. Here, we show similar levels of parasite invasion and development to the first generation of schizont in bovine epithelial-like kidney (MDBK), murine intestinal epithelial (m-IC cl2 ) and avian epithelial (CLEC-213) cells.…”