title: Sensing microorganisms in the gut triggers the immune response in Eisenia andrei earthworms.
abstract: The tube-within-tube body plan of earthworms is appropriate for studying the interactions of microorganisms with the immune system of body cavities such as the digestive tract and coelom. This study aims to describe the immune response on the molecular and cellular level in the coelomic cavity and the gut of the earthworm Eisenia andrei after experimental microbial challenge by administering two bacterial strains (Escherichia coli and Bacillus subtilis) or yeast Saccharomyces cerevisiae to the environment. The changes in mRNA levels of defense molecules (pattern recognition receptor CCF, lysozyme, fetidin/lysenins) in the coelomocytes and gut tissue were determined by quantitative PCR. The immune response at a cellular level was captured in histological sections, and the expression of CCF was localized using in situ hybridization. Coelomocytes respond to the presence of bacteria in the coelomic cavity by increasing the mRNA levels of defense molecules, especially CCF. The immune response in gut tissue is less affected by microbial stimulation because the epithelial cells of gut exhibit basically strong mRNA synthesis of ccf as a defense against the continuous microbial load in the gut lumen. The cellular immune response is mediated by coelomocytes released from the mesenchymal lining of the coelomic cavity. These combined immune mechanisms are necessary for the survival of earthworms in the microbially rich environment of soil.
authors.affiliation: Laboratory of Cellular and Molecular Immunology, Institute of Microbiology of the CAS, v. v. i., Vídeňská 1083, 142 20, Prague 4, Czech Republic.
authors.forename: Jiří
authors.initials: J
authors.lastname: Dvořák
authors.affiliation: Laboratory of Cellular and Molecular Immunology, Institute of Microbiology of the CAS, v. v. i., Vídeňská 1083, 142 20, Prague 4, Czech Republic.
authors.forename: Radka
authors.initials: R
authors.lastname: Roubalová
authors.affiliation: Laboratory of Cellular and Molecular Immunology, Institute of Microbiology of the CAS, v. v. i., Vídeňská 1083, 142 20, Prague 4, Czech Republic.
authors.forename: Petra
authors.initials: P
authors.lastname: Procházková
authors.affiliation: Laboratory of Cellular and Molecular Immunology, Institute of Microbiology of the CAS, v. v. i., Vídeňská 1083, 142 20, Prague 4, Czech Republic.
authors.forename: Pavel
authors.initials: P
authors.lastname: Rossmann
authors.affiliation: Laboratory of Cellular and Molecular Immunology, Institute of Microbiology of the CAS, v. v. i., Vídeňská 1083, 142 20, Prague 4, Czech Republic.
authors.forename: František
authors.initials: F
authors.lastname: Škanta
authors.affiliation: Laboratory of Cellular and Molecular Immunology, Institute of Microbiology of the CAS, v. v. i., Vídeňská 1083, 142 20, Prague 4, Czech Republic. Electronic address: mbilej@biomed.cas.cz.
authors.forename: Martin
authors.initials: M
authors.lastname: Bilej
mesh_terms: D000818:Animals; D001412:Bacillus subtilis / Q000276:immunology*; D004926:Escherichia coli / Q000276:immunology*; D016905:Gram-Negative Bacterial Infections / Q000276:immunology*; D016908:Gram-Positive Bacterial Infections / Q000276:immunology*; D007111:Immunity, Cellular; D018928:Immunity, Mucosal; D007413:Intestinal Mucosa / Q000276:immunology* / Q000382:microbiology / Q000821:virology; D037102:Lectins / Q000235:genetics / Q000378:metabolism*; D008648:Mesoderm / Q000276:immunology* / Q000473:pathology; D009181:Mycoses / Q000276:immunology*; D009835:Oligochaeta / Q000276:immunology*; D051192:Receptors, Pattern Recognition / Q000235:genetics / Q000378:metabolism*; D012440:Saccharomyces / Q000276:immunology*; D015854:Up-Regulation
chemical_list: D037102:Lectins; D051192:Receptors, Pattern Recognition; C094795:coelomic cytolytic factor 1, Eisenia fetida
keywords: CCF; Coelomocyte; Earthworm; Microorganism; Mucosal immunity