scholarly journals Echinochrome A Release by Red Spherule Cells Is an Iron-Withholding Strategy of Sea Urchin Innate Immunity

2017 ◽  
Vol 10 (2) ◽  
pp. 119-130 ◽  
Author(s):  
Christopher J. Coates ◽  
Claire McCulloch ◽  
Joshua Betts ◽  
Tim Whalley
Keyword(s):  
Ex Vivo ◽  
Sea Urchins ◽  
Antimicrobial Properties ◽  
Paracentrotus Lividus ◽  
Iron Chelator ◽  
Coelomic Fluid ◽  
Echinochrome A ◽  
Psammechinus Miliaris ◽  
Spherule Cell ◽  
Cellular Immune

Cellular immune defences in sea urchins are shared amongst the coelomocytes - a heterogeneous population of cells residing in the coelomic fluid (blood equivalent) and tissues. The most iconic coelomocyte morphotype is the red spherule cell (or amebocyte), so named due to the abundance of cytoplasmic vesicles containing the naphthoquinone pigment echinochrome A. Despite their identification over a century ago, and evidence of antiseptic properties, little progress has been made in characterising the immunocompetence of these cells. Upon exposure of red spherule cells from sea urchins, i.e., Paracentrotus lividus and Psammechinus miliaris, to microbial ligands, intact microbes, and damage signals, we observed cellular degranulation and increased detection of cell-free echinochrome in the coelomic fluid ex vivo. Treatment of the cells with ionomycin, a calcium-specific ionophore, confirmed that an increase in intracellular levels of Ca2+ is a trigger of echinochrome release. Incubating Gram-positive/negative bacteria as well as yeast with lysates of red spherule cells led to significant reductions in colony-forming units. Such antimicrobial properties were counteracted by the addition of ferric iron (Fe3+), suggesting that echinochrome acts as a primitive iron chelator in echinoid biological defences.

scholarly journals The Diverse Transformer (Trf) Protein Family in the Sea Urchin Paracentrotus lividus Acts through a Collaboration between Cellular and Humoral Immune Effector Arms

2021 ◽  
Vol 22 (13) ◽  
pp. 6639
Author(s):  
Iryna Yakovenko ◽  
Asaf Donnyo ◽  
Or Ioscovich ◽  
Benyamin Rosental ◽  
Matan Oren
Keyword(s):  
Sea Urchin ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Paracentrotus Lividus ◽  
Protein Family ◽  
Coelomic Fluid ◽  
Immune Gene ◽  
Immune Effector ◽  
E Coli ◽  
Humoral Immune

Sea urchins are long-living marine invertebrates with a complex innate immune system, which includes expanded families of immune receptors. A central immune gene family in sea urchins encodes the Transformer (Trf) proteins. The Trf family has been studied mainly in the purple sea urchin Strongylocentrotus purpuratus. Here, we explore this protein family in the Mediterranean Sea urchin Paracentrotus lividus. The PlTrf genes and predicted proteins are highly diverse and show a typical Trf size range and structure. Coelomocytes and cell-free coelomic fluid from P. lividus contain different PlTrf protein repertoires with a shared subset, that bind specifically to E. coli. Using FACS, we identified five different P. lividus coelomocyte sub-populations with cell surface PlTrf protein expression. The relative abundance of the PlTrf-positive cells increases sharply following immune challenge with E. coli, but not following challenge with LPS or the sea urchin pathogen, Vibrio penaeicida. Phagocytosis of E. coli by P. lividus phagocytes is mediated through the cell-free coelomic fluid and is inhibited by blocking PlTrf activity with anti-SpTrf antibodies. Together, our results suggest a collaboration between cellular and humoral PlTrf-mediated effector arms in the P. lividus specific immune response to pathogens.

scholarly journals Composition and geographic variation of the bacterial microbiota associated with the coelomic fluid of the sea urchin Paracentrotus lividus

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Teresa Faddetta ◽  
Francesco Ardizzone ◽  
Francesca Faillaci ◽  
Chiara Reina ◽  
Emilia Palazzotto ◽  
...  
Keyword(s):  
Sea Urchin ◽  
Nature Reserve ◽  
Sea Urchins ◽  
Geographical Location ◽  
Paracentrotus Lividus ◽  
Coelomic Fluid ◽  
Rrna Gene ◽  
Sequencing Analysis ◽  
Bacterial Strains ◽  
Microbiota Structure

AbstractIn the present work, culture-based and culture-independent investigations were performed to determine the microbiota structure of the coelomic fluid of Mediterranean sea urchin Paracentrotus lividus individuals collected from two distinct geographical sites neighboring a high-density population bay and a nature reserve, respectively. Next Generation Sequencing analysis of 16S rRNA gene (rDNA) showed that members of the Proteobacteria, Bacteroidetes and Fusobacteria phyla, which have been previously reported to be commonly retrieved from marine invertebrates, dominate the overall population of microorganisms colonizing this liquid tissue, with minority bacterial genera exhibiting remarkable differences among individuals. Our results showed that there is a correlation between microbiota structure and geographical location of the echinoderm collection site, highlighting over-representation of metagenomic functions related to amino acid and bioactive peptides metabolism in specimens inhabiting the nature reserve. Finally, we also described the developmental delay and aberrations exhibited by sea urchin embryos exposed to distinct bacterial isolates, and showed that these defects rely upon hydrophilic compound(s) synthesized by the bacterial strains assayed. Altogether, our findings lay the groundwork to decipher the relationships of bacteria with sea urchins in their aquatic environment, also providing an additional layer of information to understand the biological roles of the coelomic fluid.

scholarly journals The reproductive response of the sea urchins Paracentrotus lividus (G.) and Psammechinus miliaris (L.) to a hyperproteinated macrophytic diet

2006 ◽  
Vol 339 (1) ◽  
pp. 43-54 ◽  
Author(s):  
Anne-Gaëlle Jacquin ◽  
Anne Donval ◽  
Jacques Guillou ◽  
Sandra Leyzour ◽  
Eric Deslandes ◽  
...  
Keyword(s):  
Sea Urchins ◽  
Paracentrotus Lividus ◽  
Psammechinus Miliaris ◽  
Reproductive Response

scholarly journals Presence and biodistribution of perfluorooctanoic acid (PFOA) in Paracentrotus lividus highlight its potential application for environmental biomonitoring

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Dario Savoca ◽  
Raffaella Melfi ◽  
Antonio Palumbo Piccionello ◽  
Salvatore Barreca ◽  
Silvestre Buscemi ◽  
...  
Keyword(s):  
Sea Urchin ◽  
Potential Application ◽  
Sea Urchins ◽  
Paracentrotus Lividus ◽  
Posidonia Oceanica ◽  
Polluted Site ◽  
Contaminated Sites ◽  
Coelomic Fluid ◽  
Pfoa Concentration

AbstractThe first determination of presence and biodistribution of PFOA in ninety specimens of sea urchin Paracentrotus lividus from two differently contaminated sites along Palermo’s coastline (Sicily) is reported. Analyses were performed on the sea urchins’ coelomic fluids, coelomocytes, gonads or mixed organs, as well as on seawater and Posidonia oceanica leaves samples from the collection sites. PFOA concentration ranged between 1 and 13 ng/L in seawater and between 0 and 794 ng/g in P. oceanica. The analyses carried out on individuals of P. lividus from the least polluted site (A) showed PFOA median values equal to 0 in all the matrices (coelomic fluid, coelomocytes and gonads). Conversely, individuals collected from the most polluted site (B) showed median PFOA concentrations of 21 ng/g in coelomic fluid, 153 ng/g in coelomocytes, and 195 ng/g in gonads. Calculated bioconcentration factors of log10BCF > 3.7 confirmed the very bioaccumulative nature of PFOA. Significant correlations were found between the PFOA concentration of the coelomic fluid versus the total PFOA concentration of the entire sea urchin. PERMANOVA (p = 0.001) end Welch's t-test (p < 0.001) analyses showed a difference between specimens collected from the two sites highlighting the potential application of P. lividus as sentinel species for PFOA biomonitoring.

scholarly journals Sub-Chronic Effects of Slight PAH- and PCB-Contaminated Mesocosms in Paracentrotus lividus Lmk: A Multi-Endpoint Approach and De Novo Transcriptomic

2021 ◽  
Vol 22 (13) ◽  
pp. 6674
Author(s):  
Luisa Albarano ◽  
Valerio Zupo ◽  
Davide Caramiello ◽  
Maria Toscanesi ◽  
Marco Trifuoggi ◽  
...  
Keyword(s):  
De Novo ◽  
Sea Urchins ◽  
Transcriptome Assembly ◽  
Paracentrotus Lividus ◽  
Marine Biota ◽  
De Novo Transcriptome Assembly ◽  
De Novo Transcriptome ◽  
Limit Values ◽  
The Impact ◽  
Endpoint Approach

Sediment pollution is a major issue in coastal areas, potentially endangering human health and the marine environments. We investigated the short-term sublethal effects of sediments contaminated with polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) on the sea urchin Paracentrotus lividus for two months. Spiking occurred at concentrations below threshold limit values permitted by the law (TLVPAHs = 900 µg/L, TLVPCBs = 8 µg/L, Legislative Italian Decree 173/2016). A multi-endpoint approach was adopted, considering both adults (mortality, bioaccumulation and gonadal index) and embryos (embryotoxicity, genotoxicity and de novo transcriptome assembly). The slight concentrations of PAHs and PCBs added to the mesocosms were observed to readily compartmentalize in adults, resulting below the detection limits just one week after their addition. Reconstructed sediment and seawater, as negative controls, did not affect sea urchins. PAH- and PCB-spiked mesocosms were observed to impair P. lividus at various endpoints, including bioaccumulation and embryo development (mainly PAHs) and genotoxicity (PAHs and PCBs). In particular, genotoxicity tests revealed that PAHs and PCBs affected the development of P. lividus embryos deriving from exposed adults. Negative effects were also detected by generating a de novo transcriptome assembly and its annotation, as well as by real-time qPCR performed to identify genes differentially expressed in adults exposed to the two contaminants. The effects on sea urchins (both adults and embryos) at background concentrations of PAHs and PCBs below TLV suggest a need for further investigations on the impact of slight concentrations of such contaminants on marine biota.

scholarly journals Age-related NADH oxidase (arNOX) activity is significantly reduced in coelomic fluid of long-lived sea urchins

2013 ◽  
Vol 5 (1) ◽  
pp. 2
Author(s):  
Eric Talbert ◽  
Andrea Bodnar ◽  
Dorothy M Morré ◽  
D James Morré
Keyword(s):  
Nadh Oxidase ◽  
Sea Urchins ◽  
Coelomic Fluid ◽  
Age Related

scholarly journals The Anthrax Vaccine Adsorbed Vaccine Generates Protective Antigen (PA)-Specific CD4+ T Cells with a Phenotype Distinct from That of Naïve PA T Cells

2008 ◽  
Vol 76 (10) ◽  
pp. 4538-4545 ◽  
Author(s):  
William W. Kwok ◽  
Junbao Yang ◽  
Eddie James ◽  
John Bui ◽  
Laurie Huston ◽  
...  
Keyword(s):  
T Cells ◽  
Mononuclear Cells ◽  
Protective Antigen ◽  
Ex Vivo ◽  
Cytokine Profile ◽  
T Cell Epitopes ◽  
Peripheral Blood Mononuclear ◽  
Anthrax Vaccine ◽  
Cellular Immune

ABSTRACT Cellular immune responses against protective antigen (PA) of Bacillus anthracis in subjects that received the anthrax vaccine adsorbed (AVA) vaccine were examined. Multiple CD4+ T-cell epitopes within PA were identified by using tetramer-guided epitope mapping. PA-reactive CD4+ T cells with a CD45RA− phenotype were also detected by direct ex vivo staining of peripheral blood mononuclear cells (PBMC) with PA-specific tetramers. Surprisingly, PA-specific T cells were also detected in PBMC of nonvaccinees after a single cycle of in vitro PA stimulation. However, PA-reactive CD4+ T cells in nonvaccinees occurred at lower frequencies than those in vaccinees. The majority of PA-reactive T cells from nonvaccinees were CD45RA+ and exhibited a Th0/Th1 cytokine profile. In contrast, phenotyping and cytokine profile analyses of PA-reactive CD4+ T cells from vaccinees indicated that vaccination leads to commitment of PA-reactive T cells to a Th2 lineage, including generation of PA-specific, pre-Th2 central memory T cells. These results demonstrate that the current AVA vaccine is effective in skewing the development of PA CD4+ T cells to the Th2 lineage. The data also demonstrated the feasibility of using class II tetramers to analyze CD4+ cell responses and lineage development after vaccination.

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