Attività antibatterica di peptidi estratti da celomociti di echinodermi

Negli echinodermi la difesa dell’organismo dalle invasioni microbiche avviene tramite meccanismi cellulari e umorali dell’immunità innata. Una componente fondamentale dei fattori umorali è costituita dai peptidi antimicrobici (AMPs) molto conservati con un ampio spettro di attività antimicrobica contro batteri, virus e funghi. Solitamente gli AMPs sono costituiti da meno di 100 amminoacidi, sono cationici e formano strutture anfipatiche. In questo lavoro dimostriamo che i celomociti dell’Echinoideo Paracentrotus lividus e dell’Oloturoideo Holothuria tubulosa contengono sostanze con attività antimicrobica verso diversi ceppi batterici patogeni umani. In entrambe le specie, nel precipitato ac…

A D-galactose specific lectin is an inducible inflammatory IL-1-like opsonin in the hemolymph of the ascidian Ciona intestinalis challegend with LPS.

Novel antimicrobial and anti-biofilm agents from a marine invertebrate

Natural immunity in Paracentrotus lividus: coelomocyte cooperation

A lytic mechanism based on soluble phospholypases A2 (sPLA2) and b-galactoside specific lectins is exerted by Ciona intestinalis (ascidian) unilocular refractile hemocytes against K562 cell line and mammalian erythrocytes

Abstract Hemocytes from the ascidian Ciona intestinalis exert in vitro Ca 2+ -dependent cytotoxic activity toward mammalian erythrocytes and K562 cells. To examine the lytic mechanism, hemocyte populations were separated (B1–B6 bands) through a Percoll discontinuous density gradient, the hemocyte cytotoxic activity (HCA) and the lytic activity of the hemocyte lysate supernatant (HLS) were assayed. In addition the separated hemocytes were cultured and the cell-free culture medium (CFM) assayed after 3 h culture. Results support that unilocular refractile hemocytes (URGs), enriched in B5, are cytotoxic. The B5-HLS contains lysins and the activity of B5-CFM shows that lysins can be released in…

First evidences of Toll like receptor on Paracentrotus livisua coelomocytes.

Invertebrate lectins present cytokine properties.

Enhanced expression of a cloned and sequenced Ciona intestinalis TNFa-like (CiTNFa) gene during the LPS-induced inflammatory response.

A tumor necrosis factor-alpha (TNFalpha)-like gene from Ciona intestinalis (CiTNF alpha-like) body wall challenged with bacterial lipopolysaccharide (LPS) was cloned and sequenced 4 h after LPS inoculation. An open reading frame of 936 bp encoding a propeptide of 312 amino acids (35.4 kDa) displaying a transmembrane domain from positions 7 to 29, a TACE cleavage site, and a mature peptide domain of 185 amino acids (20.9 kDa), was determined with a predicted isoelectric point of 9.4. The phylogenetic tree based on deduced amino acid sequences of invertebrate TNF-like protein and vertebrate TNFs supported the divergence between the ascidian and vertebrate TNF families, whereas D. melanogaster…

Effetti modulanti del poliacrilato sulla tossicità del TMT-CI in immunociti di Paracentrotus lividus.

Tunicate immunocytes can be cytotoxic toward foreign cells

Sphingomyelin as well as carbohydrates are involved in the mechanism of cytotoxic molecules contained and released in vitro by Ciona intestinalis granulocytes.

Espressione della proteina di resistenza multixenobiotica (MXR) in Mytilus galloprovincialis in aree tirreniche meridionali

Effect of exposure cadmium on the echinoderm Paracentrotus lividus (Echinoidea)

Preliminary results on antimicrobial activity of Rhynchophorous ferrugineus hemolymph

Rhynchophorus ferrugineus (Coleoptera: Curculionidae), known as the Red Palm Weevil (RPW) and accidentally introduced in the Mediterranean areas, is considered a quarantine pest for tree palms especially in the urban environment. In order to understand the relationship among potential pathogens and RPW several studies were carried out on RPW immune system. Here we report the results of a preliminary study undertaken to investigate the effect of naturally occurring antimicrobial activities present both in the cell free hemolymph and in hemocytes lysate supernatant of RPW. The hemolymph was extracted from the older larvae sampled from infested palm trees. The protein fractions were extracted …

HEAT SHOCK POTEINS (HSP) IN BRACHIDONTES PHARAONIS (MOLLUSCA, BIVALVIA) AT VARYING TEMPERATURES

Effetti del cadmio sulle attività cellulari dell’echinoderma Paracentrotus lividus (Echinoidea)

An Attempt to re-examine the immune role of Ciona intestinalis hemocytes

Evoluzione dell’immunità innata. Componenti della reazione infiammatoria indotta da LPS nella parete corporea dell’ascidia Ciona intestinalis.

Gender differences in the immune system activities of sea urchin Paracentrotus lividus

In the immune system of vertebrates, gender-specific differences in individual immune competence are well known. In general, females possess more powerful immune response than males. In invertebrates, the situation is much less clear. For this purpose we have chosen to study the immune response of the two sexes of the echinoderm Paracentrotus lividus in pre- and post-spawning phases. The coelomic fluid from the echinoderms contains several coelomocyte types and molecules involved in innate immune defenses. In this article we report that the degree of immune responses in the P. lividus differs according to sex in both pre- and post-spawning phases. We found in all tests that females were mor…

Enhanced CiTNFα expression is an inflammatory response of the ascidian Ciona intestinalis

Cell cooperation in coelomocyte cytotoxic activity of Paracentrotus lividus coelomocytes

The coelomic fluid from the sea urchin Paracentrotus lividus contains several coelomocyte types including amoebocytes and uncoloured spherulocytes involved in immune defences. In the present paper, we show a Ca(2+)-dependent cytotoxic activity for the unfractionated coelomocytes assayed in vitro, with rabbit erythrocytes and the K562 tumour cell line. In a plaque-forming assay, whole coelomocyte preparations as well as density gradient separated coelomocyte populations revealed that cell populations enriched in uncoloured spherulocytes, exerted high cytotoxic activity by releasing lysins in the presence of amoebocytes. This cooperative effect could be dependent on soluble factors released b…

Modulazione di heat shock protein (HSP) in Brachidontes pharaonis (Mollusca, Bivalvia) in condizioni di temperatura variabile

Molecules and cells in inflammatory responses of the ascidian Ciona intestinalis

La risposta infiammatoria in Ciona intestinalis è caratterizzata dall’aumento di lectine specifiche per D-galattosidi e dall’espressione di collagene FACIT di tipo IX

Effetti del cadmio sulla fagocitosi e sull'attività di formazione di placche di lisi dei celomociti di Parcentrotus lividus

Evolution of Innate Immunity. Components of inflammatory reaction in Ciona intestinalis

Meccanismi dell’immunità naturale in echinodermi. Interazioni tra i celomociti di Paracentrotus lividus

Enhanced expression of a CinTNF gene in the LPS challenged inflammatiry responses of the ascidian Ciona intestinalis

Inflammatory response of Ciona intestinalis involve enhanced D-galactoside-specific lectins and FACIT collagen expression.

Inducible lectins with galectin properties and human IL1alpha epitopes opsonize yeast during the inflammatory response of the ascidian Ciona intestinalis.

Studies on inducible ascidian lectins may shed light on the evolutionary emergence of cytokine functions. Here, we show that the levels of opsonins, with IL1alpha-epitopes, increase in Ciona intestinalis hemolymph as a response to an inflammatory stimulus and, in particular, to intratunic injection of lipopolysaccharide (LPS). The inflammatory agent promptly (within 4 h) enhances Ca(2+)-independent serum hemagglutinating and opsonizing activities, which are both inhibited by D-galactose and D-galactosides (alpha-lactose, N-acetyl-D-lactosamine, thio-digalactoside), suggesting that anti-rabbit erythrocyte lectins with galectin properties are involved as opsonins. Inducible galectin molecules…

Effect of cadmium exposure on phagocytosis and plaque lysis activity of Paracentrotus lividus coelomocyte

Cooperazione cellulare nella reazione citotossica dei celomociti di Paracentrotus lividus