Nematode assemblage response to fish-farm impact in vegetated (Posidonia oceanica) and non‑vegetated habitats

We investigated the impact of fish farming on the benthic biota of 2 habitats (seagrass meadows of Posidonia oceanica and non-vegetated soft bottoms), by examining in detail the nematode assemblages, and the effects of organic enrichment on their abundance, diversity (species richness and trophic diversity), community structure and individual size. All investigated faunal variables differed significantly between impact and control sediments, except for individual nematode biomass. Nematodes displayed reduced biodiversity beneath the investigated fish farms in both vegetated and non-vegetated habitats. The nematode genera Richtersia, Desmoscolex and Halalaimus were highly sensitive to biodeposition and disappeared almost completely in farm sediments, whereas other genera such as Daptonema and Prochromadorella largely increased their relative abundance. The impact of biodeposition was investigated also in terms of K-dominance curves and functional variables (life strategies as maturity index, and functional [i.e. trophic] diversity) which showed that nematodes are very sensitive to this kind of environmental disturbance. Our results indicate that the analysis of nematode assemblage composition, the life traits of the dominant species and the presence/disappearance of certain nematode species represent a reliable tool for monitoring the quality state of marine sediments exposed to fish-farm organic wastes

Identification of new autoantigens by protein array indicates a role for IL4 neutralization in Autoimmune Hepatitis.

none25siAutoimmune hepatitis (AIH) is an unresolving inflammation of the liver of unknown cause. Diagnosis requires the exclusion of other conditions and the presence of characteristic features such as specific autoantibodies. Presently, these autoantibodies have relatively low sensitivity and specificity and are identified via immunostaining of cells or tissues; therefore, there is a diagnostic need for better and easy-to-assess markers. To identify new AIH-specific autoantigens, we developed a protein microarray comprising 1626 human recombinant proteins, selected in silico for being secreted or membrane associated. We screened sera from AIH patients on this microarray and compared the reactivity with that of sera from healthy donors and patients with chronic viral hepatitis C. We identified six human proteins that are specifically recognized by AIH sera. Serum reactivity to a combination of four of these autoantigens allows identification of AIH patients with high sensitivity (82%) and specificity (92%). Of the six autoantigens, the interleukin-4 (IL4) receptor fibronectin type III domain of the IL4 receptor (CD124), which is expressed on the surface of both lymphocytes and hepatocytes, showed the highest individual sensitivity and specificity for AIH. Remarkably, patients' sera inhibited STAT6 phosphorylation induced by IL4 binding to CD124, demonstrating that these autoantibodies are functional and suggesting that IL4 neutralization has a pathogenetic role in AIH.noneZingaretti C; Arigo' M; Cardaci A; Moro M; Crosti M; Sinisi A; Sugliano E; Cheroni C; Marabita F; Nogarotto R; Bonnal RJ; Marcatili P; Marconi M; Zignego A; Muratori P; Invernizzi P; Colombatto P; Brunetto M; Bonino F; De Francesco R; Geginat J; Pagani M; Muratori L; Abrignani S; Bombaci M.Zingaretti C; Arigo' M; Cardaci A; Moro M; Crosti M; Sinisi A; Sugliano E; Cheroni C; Marabita F; Nogarotto R; Bonnal RJ; Marcatili P; Marconi M; Zignego A; Muratori P; Invernizzi P; Colombatto P; Brunetto M; Bonino F; De Francesco R; Geginat J; Pagani M; Muratori L; Abrignani S; Bombaci M

Yeast killer toxin-like candidacidal Ab6 antibodies elicited through the manipulation of the idiotypic cascade

A mouse anti-anti-anti-idiotypic (Id) IgM monoclonal antibody (mAb K20, Ab4), functionally mimicking a Wyckerhamomyces anomalus (Pichia anomala) killer toxin (KT) characterized by fungicidal activity against yeasts presenting specific cell wall receptors (KTR) mainly constituted by beta-1,3-glucan, was produced from animals presenting anti-KT Abs (Ab3) following immunization with a rat IgM anti-Id KT-like mAb (mAb K10, Ab2). MAb K10 was produced by immunization with a KTneutralizing mAb (mAb KT4, Ab1) bearing the internal image of KTR. MAb K20, likewise mAb K10, proved to be fungicidal in vitro against KT-sensitive Candida albicans cells, an activity neutralized by mAb KT4, and was capable of binding to beta-1,3- glucan. MAb K20 and mAb K10 competed with each other and with KT for binding to C. albicans KTR. MAb K20 was used to identify peptide mimics of KTR by the selection of phage clones from random peptide phage display libraries. Using this strategy, four peptides (TK 1-4) were selected and used as immunogen in mice in the form of either keyhole limpet hemocyanin (KLH) conjugates or peptide-encoding minigenes. Peptide and DNA immunization could induce serum Abs characterized by candidacidal activity, which was inhibited by laminarin, a soluble beta-1,3-glucan, but not by pustulan, a beta-1,6- glucan. These findings show that the idiotypic cascade can not only overcome the barrier of animal species but also the nature of immunogens and the type of technology adopted