title: Human recombinant RNASET2-induced inflammatory response and connective tissue remodeling in the medicinal leech.
abstract: In recent years, several studies have demonstrated that the RNASET2 gene is involved in the control of tumorigenicity in ovarian cancer cells. Furthermore, a role in establishing a functional cross-talk between cancer cells and the surrounding tumor microenvironment has been unveiled for this gene, based on its ability to act as an inducer of the innate immune response. Although several studies have reported on the molecular features of RNASET2, the details on the mechanisms by which this evolutionarily conserved ribonuclease regulates the immune system are still poorly defined. In the effort to clarify this aspect, we report here the effect of recombinant human RNASET2 injection and its role in regulating the innate immune response after bacterial challenge in an invertebrate model, the medicinal leech. We found that recombinant RNASET2 injection induces fibroplasias, connective tissue remodeling and the recruitment of numerous infiltrating cells expressing the specific macrophage markers CD68 and HmAIF1. The RNASET2-mediated chemotactic activity for macrophages has been further confirmed by using a consolidated experimental approach based on injection of the Matrigel biomatrice (MG) supplemented with recombinant RNASET2 in the leech body wall. One week after injection, a large number of CD68+and HmAIF-1+macrophages massively infiltrated MG sponges. Finally, in leeches challenged with lipopolysaccharides (LPS) or with the environmental bacteria pathogen Micrococcus nishinomiyaensis, numerous macrophages migrating to the site of inoculation expressed high levels of endogenous RNASET2. Taken together, these results suggest that RNASET2 is likely involved in the initial phase of the inflammatory response in leeches.
authors.affiliation: Department of Biotechnology and Life Sciences, University of Insubria, Via J. H. Dunant 3, 21100, Varese, Italy.
authors.forename: Nicolò
authors.initials: N
authors.lastname: Baranzini
authors.affiliation: Department of Biotechnology and Life Sciences, University of Insubria, Via J. H. Dunant 3, 21100, Varese, Italy.
authors.forename: Edoardo
authors.initials: E
authors.lastname: Pedrini
authors.affiliation: Department of Biotechnology and Life Sciences, University of Insubria, Via J. H. Dunant 3, 21100, Varese, Italy.
authors.forename: Rossana
authors.initials: R
authors.lastname: Girardello
authors.affiliation: Department of Biotechnology and Life Sciences, University of Insubria, Via J. H. Dunant 3, 21100, Varese, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Tettamanti
authors.affiliation: Department of Biotechnology and Life Sciences, University of Insubria, Via J. H. Dunant 3, 21100, Varese, Italy.
authors.forename: Magda
authors.initials: M
authors.lastname: de Eguileor
authors.affiliation: Department of Biotechnology and Life Sciences, University of Insubria, Via J. H. Dunant 3, 21100, Varese, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Taramelli
authors.affiliation: Department of Biotechnology and Life Sciences, University of Insubria, Via J. H. Dunant 3, 21100, Varese, Italy. francesco.acquati@uninsubria.it.
authors.forename: Francesco
authors.initials: F
authors.lastname: Acquati
authors.affiliation: Department of Biotechnology and Life Sciences, University of Insubria, Via J. H. Dunant 3, 21100, Varese, Italy. annalisa.grimaldi@uninsubria.it.
authors.forename: Annalisa
authors.initials: A
authors.lastname: Grimaldi
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism; D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D003094:Collagen / Q000378:metabolism; D003238:Connective Tissue / Q000187:drug effects / Q000473:pathology*; D016616:Cryoultramicrotomy; D004338:Drug Combinations; D057075:Enzyme Assays; D005455:Fluorescent Antibody Technique; D047709:Hirudo medicinalis / Q000033:anatomy & histology / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D006801:Humans; D007249:Inflammation / Q000473:pathology*; D007797:Laminin / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D011509:Proteoglycans / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology*; D012260:Ribonucleases / Q000494:pharmacology*; D025521:Tumor Suppressor Proteins / Q000494:pharmacology*
chemical_list: D004338:Drug Combinations; D007797:Laminin; D008070:Lipopolysaccharides; D011509:Proteoglycans; D011994:Recombinant Proteins; D025521:Tumor Suppressor Proteins; C059485:matrigel; D003094:Collagen; D012260:Ribonucleases; C425232:RNASET2 protein, human; D000135:Acid Phosphatase
keywords: Hirudo; Immune response; Inflammation; Macrophages; T2 RNases