TNFalpha-induced long pentraxin PTX3 expression in human lung epithelial cells via JNK

Association of PTX3 gene polymorphisms and PTX3 plasma levels with leprosy susceptibility

BACKGROUND

Pentraxin 3 (PTX3) is a soluble pattern recognition receptor that plays a crucial role in modulating the inflammatory response and activating the complement system. Additionally, plasma PTX3 has emerged as a potential biomarker for various infectious diseases. The aim of this study was to evaluate the association of PTX3 gene polymorphisms and PTX3 plasma levels with susceptibility to leprosy and clinical characteristics.

METHODS

Patients with leprosy from a hyperendemic area in the Northeast Region of Brazil were included. Healthy household contacts and healthy blood donors from the same geographical area were recruited as a control group. The rs1840680 and rs2305619 polymorphisms of PTX3 were determined by real-time PCR. Plasma levels of PTX3 were determined by ELISA.

RESULTS

A total of 512 individuals were included. Of these, 273 were patients diagnosed with leprosy; 53 were household contacts, and 186 were healthy blood donors. No association was observed between PTX3 polymorphisms and susceptibility to leprosy or development of leprosy reaction or physical disability. On the other hand, plasma levels of PTX3 were significantly higher in patients with leprosy when compared to household contacts (p = 0.003) or blood donors (p = 0.04). It was also observed that PTX3 levels drop significantly after multidrug therapy (p < 0.0001).

CONCLUSIONS

Our results suggest that PTX3 may play an important role in the pathogenesis of leprosy and point to the potential use of this molecule as an infection marker.

Pentraxins in invertebrates and vertebrates: From structure, function and evolution to clinical applications

The immune system is divided into two broad categories, consisting of innate and adaptive immunity. As recognition and effector factors of innate immunity and regulators of adaptive immune responses, lectins are considered to be important defense chemicals against microbial pathogens, cell trafficking, immune regulation, and prevention of autoimmunity. Pentraxins, important members of animal lectins, play a significant role in protecting the body from pathogen infection and regulating inflammatory reactions. They can recognize and bind to a variety of ligands, including carbohydrates, lipids, proteins, nucleic acids and their complexes, and protect the host from pathogen invasion by activating the complement cascade and Fcγ receptor pathways. Based on the primary structure of the subunit, pentraxins are divided into short and long pentraxins. The short pentraxins are comprised of C-reactive protein (CRP) and serum amyloid P (SAP), and the most important member of the long pentraxins is pentraxin 3 (PTX3). The CRP and SAP exist in both vertebrates and invertebrates, while the PTX3 may be present only in vertebrates. The major ligands and functions of CRP, SAP and PTX3 and three activation pathways involved in the complement system are summarized in this review. Their different characteristics in various animals including humans, and their evolutionary trees are analyzed. The clinical applications of CRP, SAP and PTX3 in human are reviewed. Some questions that remain to be understood are also highlighted.

PRMT1 driven PTX3 regulates ferritinophagy in glioma

Mutations in the Krebs cycle enzyme IDH1 (isocitrate dehydrogenase (NADP(+)) 1) are associated with better prognosis in gliomas. Though IDH1 mutant (IDH1R132H) tumors are characterized by their antiproliferative signatures maintained through hypermethylation of DNA and chromatin, mechanisms affecting cell death pathways in these tumors are not well elucidated. On investigating the crosstalk between the IDH1 mutant epigenome, ferritinophagy and inflammation, diminished expression of PRMT1 (protein arginine methyltransferase 1) and its associated asymmetric dimethyl epigenetic mark H4R3me2a was observed in IDH1R132H gliomas. Reduced expression of PRMT1 was concurrent with diminished levels of PTX3, a key secretory factor involved in cancer-related inflammation. Lack of PRMT1 H4R3me2a in IDH1 mutant glioma failed to epigenetically activate the expression of PTX3 with a reduction in YY1 (YY1 transcription factor) binding on its promoter. Transcriptional activation and subsequent secretion of PTX3 from cells was required for maintaining macroautophagic/autophagic balance as pharmacological or genetic ablation of PTX3 secretion in wild-type IDH1 significantly increased autophagic flux. Additionally, PTX3-deficient IDH1 mutant gliomas exhibited heightened autophagic signatures. Furthermore, we demonstrate that the PRMT1-PTX3 axis is important in regulating the levels of ferritin genes/iron storage and inhibition of this axis triggered ferritinophagic flux. This study highlights the conserved role of IDH1 mutants in augmenting ferritinophagic flux in gliomas irrespective of genetic landscape through inhibition of the PRMT1-PTX3 axis. This is the first study describing ferritinophagy in IDH1 mutant gliomas with mechanistic details. Of clinical importance, our study suggests that the PRMT1-PTX3 ferritinophagy regulatory circuit could be exploited for therapeutic gains.Abbreviations: 2-HG: D-2-hydroxyglutarate; BafA1: bafilomycin A1; ChIP: chromatin immunoprecipitation; FTH1: ferritin heavy chain 1; FTL: ferritin light chain; GBM: glioblastoma; HMOX1/HO-1: heme oxygenase 1; IHC: immunohistochemistry; IDH1: isocitrate dehydrogenase(NADP(+))1; MDC: monodansylcadaverine; NCOA4: nuclear receptor coactivator 4; NFE2L2/Nrf2: NFE2 like bZIP transcription factor 2; PTX3/TSG-14: pentraxin 3; PRMT: protein arginine methyltransferase; SLC40A1: solute carrier family 40 member 1; Tan IIA: tanshinone IIA; TCA: trichloroacetic acid; TEM: transmission electron microscopy; TNF: tumor necrosis factor.

Quantitative Evaluation of Pentraxin-3 in Peri-Miniscrew Implant Crevicular Fluid in Patients Undergoing Orthodontic Treatment: A Prospective Study

OBJECTIVE

To assess the levels of Pentraxin-3 (PTX3) in peri-miniscrew implant crevicular fluid (PMICF) before and after orthodontic force application Material and Methods: This study included 40 miniscrew implants (MSI) sites in 11 orthodontic patients with high arch discrepancy requiring first premolar extraction using maximum anchorage mechanics for the retraction of anterior teeth. After alignment, the en-masse anterior retraction was carried out using the MSI-supported direct anchorage method. PMICF was collected from the crevice of MSI using Periopaper strips 1.2µl (Oraflow Inc. USA) after one hour, 24 hours, and three weeks of MSI insertion and after one hour, 24 hours, seven days, three weeks, and six weeks of the force application. Samples were quantitatively analyzed for PTX3 levels through enzyme-linked immunosorbent assay (ELISA).

RESULTS

The trend in the change of PTX3 levels was evaluated using the Wilcoxon signed-rank test. The mean concentration of PTX3 immediately after MSI insertion was 1.19 ng/ml, significantly higher than after 3 weeks after MSI insertion (0.72 ng/ml), which may correspond to the baseline. After loading, the mean PTX3 concentration increased significantly with the peak at 24 hrs (1.28 ng/ml), followed by a gradual decline till the completion of the study (0.5 ng/ml).

CONCLUSION

After MSI insertion, a rise in PTX3 levels in PMICF suggests an underlying inflammatory process. The slow decline in PTX3 level and return to the baseline after loading suggests an adaptive bone response to the stimulus.

Pentraxin 3 Facilitates Shrimp-Allergic Responses in IgE-Activated Mast Cells

Background. Since food avoidance is currently the only way to prevent allergic reactions to shrimp, a better understanding of molecular events in the induction and progression of allergy, including food allergy, is needed for developing strategies to inhibit allergic responses. Pentraxin 3 (PTX3) is rapidly produced directly from inflammatory or damaged tissues and is involved in acute immunoinflammatory responses. However, the role of PTX3 in the development of immediate IgE-mediated shrimp allergy remains unknown. Methods. Wild-type BALB/c mice were immunized intraperitoneally and were challenged with shrimp extract. Serum IgE and PTX3 levels were analyzed. RBL-2H3 cells were stimulated with either dinitrophenyl (DNP) or serum of shrimp-allergic mice, and markers of degranulation, proinflammatory mediators, and phosphorylation of signal proteins were analyzed. We further examined the effect of PTX3 in shrimp extract-induced allergic responses in vitro and in vivo. Results. Mice with shrimp allergy had increased PTX3 levels in the serum and small intestine compared with healthy mice. PTX3 augmented degranulation, the production of proinflammatory mediators, and activation of the Akt and MAPK signaling pathways in mast cells upon DNP stimulation. Furthermore, the expression of transcription factor CCAAT/enhancer-binding protein delta (CEBPD) was elevated in PTX3-mediated mast cell activation. Finally, the PTX3 inhibitor RI37 could attenuate PTX3-induced degranulation, proinflammatory mediator expression, and phosphorylation of the Akt and MAPK signaling. Conclusions. The results suggested that PTX3 can facilitate allergic responses. Our data provide new insight to demonstrate that PTX3 is a cause of allergic inflammation and that RI37 can serve as a therapeutic agent in shrimp allergy.

RETRACTED: The pathogenicity of COVID-19 and the role of pentraxin-3: An updated review study

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief. In investigating concerns regarding the contributions of the authors to this article, the editors reached out to the authors for an explanation. In addition to the concerns regarding the contribution of each author, the editors discovered suspicious changes in authorship between the original submission and the revised version of this paper. The names of the authors Ameer A Alameri and Zanko Hassan Jawhar were added to the revised version of the article without explanation and without the exceptional approval by the handling Editor, which is contrary to the journal policy on changes to authorship. The authors were unable to provide a reasonable explanation for either of the issues raised. The editor therefore feels that the findings of the manuscript cannot be relied upon and that the article needs to be retracted.

Serum pentraxin 3 concentration correlates with disease severity in patients with myasthenia gravis

OBJECTIVE

Myasthenia gravis (MG) is an antibody-mediated inflammatory disease affecting post-synaptic membranes of neuromuscular junctions, and objective biomarkers of MG disease activity are lacking. Pentraxin 3 (PTX3) is an acute-phase inflammatory glycoprotein in the same family as C-reactive protein that is associated with disease activity in several autoimmune disorders. Thus, we investigated whether circulating PTX3 is a useful biomarker of MG activity.

METHODS

Serum PTX3 was measured in 40 patients with MG who were positive for anti-acetylcholine receptor antibody, and in 30 healthy and disease controls, using a commercial enzyme-linked immunosorbent assay kit. In patients with MG, the correlation of serum PTX3 levels with disease severity scales at serum sampling, including MG Foundation of America (MGFA) classification, MG activity of daily living (MG-ADL) score, and quantitative MG (QMG) score, were investigated.

RESULTS

Although there was no significant difference in serum PTX3 between the MG and control groups (mean, 3346 pg/mL in MG group vs. 2870 pg/mL in control group, P = 0.56), serum PTX3 moderately correlated with all disease severity scores (MGFA classification: Spearman's ρ = 0.53, P = 0.0004; MG-ADL score: Spearman's ρ = 0.45, P = 0.004; QMG score: Spearman's ρ = 0.50, P = 0.004).

CONCLUSION

Our results suggest that circulating PTX3 may reflect the extent of neuromuscular junction damage and might be involved in the pathogenesis of MG.

PTX3 alleviates hard metal-induced acute lung injury through potentiating efferocytosis

Prolonged exposure to hard metal dust results in hard metal lung disease (HMLD) characterized by respiratory symptoms. Understanding the pathogenesis and pathological process of HMLD would be helpful for its early diagnosis and treatment. In this study, we established a mouse model of hard metal-induced acute lung injury through one-time intratracheal instillation of WC-Co dust suspension. We found that WC-Co treatment damaged the lungs of mice, leading to increased production of IL-1β, TNF-α, IL-6 and IL-18, inflammatory cells infiltration and apoptosis. In vitro, WC-Co induced cytotoxicity, inflammatory response and apoptosis in macrophages (PMA-treated THP-1) and epithelial cells (A549) in a dose-dependent manner. Moreover, RNA-sequence and validation experiments verified that Pentraxin 3 (PTX3), an important mediator in the regulation of inflammation, was elevated both in vivo and in vitro induced by WC-Co. Functional experiments confirmed the PTX3, which was located on the membrane of apoptotic cells, promoted macrophage efferocytosis efficiently. This progress could help block the lung inflammation and contribute to the rapid recovery of WC-Co-induced acute lung injury. These observations provide a further understanding of the molecular mechanism of WC-Co-induced pulmonary injury and disclose PTX3 as a new potential therapeutic approach to relieve WC-Co-induced acute lung injury via efferocytosis.

New Insights on the Role of pentraxin-3 in Allergic Asthma

Pentraxins are soluble pattern recognition receptors that play a major role in regulating innate immune responses. Through their interaction with complement components, Fcγ receptors, and different microbial moieties, Pentraxins cause an amplification of the inflammatory response. Pentraxin-3 is of particular interest since it was identified as a biomarker for several immune-pathological diseases. In allergic asthma, pentraxin-3 is produced by immune and structural cells and is up-regulated by pro-asthmatic cytokines such as TNFα and IL-1β. Strikingly, some recent experimental evidence demonstrated a protective role of pentraxin-3 in chronic airway inflammatory diseases such as allergic asthma. Indeed, reduced pentraxin-3 levels have been associated with neutrophilic inflammation, Th17 immune response, insensitivity to standard therapeutics and a severe form of the disease. In this review, we will summarize the current knowledge of the role of pentraxin-3 in innate immune response and discuss the protective role of pentraxin-3 in allergic asthma.

Recent advances in pharmacological diversification of Src family kinase inhibitors

Background

Src kinase, a nonreceptor protein-tyrosine kinase is composed of 11 members (in human) and is involved in a wide variety of essential functions required to sustain cellular homeostasis and survival.

Main body of the abstract

Deregulated activity of Src family kinase is related to malignant transformation. In 2001, Food and Drug Administration approved imatinib for the treatment of chronic myeloid leukemia followed by approval of various other inhibitors from this category as effective therapeutics for cancer patients. In the past decade, Src family kinase has been investigated for the treatment of diverse pathologies in addition to cancer. In this regard, we provide a systematic evaluation of Src kinase regarding its mechanistic role in cancer and other diseases. Here we comment on preclinical and clinical success of Src kinase inhibitors in cancer followed by diabetes, hypertension, tuberculosis, and inflammation.

Short conclusion

Studies focusing on the diversified role of Src kinase as potential therapeutical target for the development of medicinally active agents might produce significant advances in the management of not only various types of cancer but also other diseases which are in demand for potent and safe therapeutics.

Pentraxin 3 expression in lungs and neutrophils of calves

Bacterial lung disease caused by Mannheimia haemolytica inflict significant mortality and morbidity resulting in enormous economic losses to cattle industry. The use of antibiotics is becoming more challenging because of development of anti-microbial resistance. The innate immune system plays a critical role in the initiation of immune response in the lung. Pentraxin 3 (PTX3), a pattern-recognition receptor is produced at sites of inflammation by many cell types, recognizes and binds to many pathogens, activates the complement cascade, and has a role in the clearance of apoptotic and necrotic cells. Because there are very few data on the expression of PTX3 in the lungs, we examined PTX3 expression in lungs of normal and M. haemolytica-infected calves and normal and E. coli lipopolysaccharide-treated cattle neutrophils using light and electron microscopic immunochemistry and Western blots. Immunohistology showed the presence of PTX3 in airway epithelial cells, alveolar septa and macrophages in normal and inflamed lungs of calves and the blots showed a significant increase in the expression of PTX3 in lungs from infected calves. Immuno-gold electron microscopy showed PTX3 in the nuclei, cytoplasm, and vesicular organelles of alveolar macrophages, endothelial cells and pulmonary intravascular macrophages (PIMs). Immunohistochemical staining for PTX3 in peripheral blood neutrophils shows an altered staining pattern in neutrophils stimulated with lipopolysachharide (LPS). However, western blots no significant change in PTX3 amount in LPS-treated neutrophils compared to the controls. These are the first data on the expression of PTX3 in the lungs and the neutrophils of cattle which may add to our understanding of innate immunity in cattle lungs.

Endogenous Long Pentraxin 3 Exerts a Protective Role in a Murine Model of Pulmonary Fibrosis

Pulmonary fibrosis is a progressive scarring disease of the lungs, characterized by inflammation, fibroblast activation, and deposition of extracellular matrix. The long pentraxin 3 (PTX3) is a member of the pentraxin family with non-redundant functions in innate immune responses, tissue repair, and haemostasis. The role played in the lungs by PTX3 during the fibrotic process has not been elucidated. In this study, the impact of PTX3 expression on lung fibrosis was assessed in an intratracheal bleomycin (BLM)-induced murine model of the disease applied to wild type animals, transgenic mice characterized by endothelial overexpression and stromal accumulation of PTX3 (Tie2-PTX3 mice), and genetically deficient Ptx3^−/− animals. Our data demonstrate that PTX3 is produced during BLM-induced fibrosis in wild type mice, and that PTX3 accumulation in the stroma compartment of Tie2-PTX3 mice limits the formation of fibrotic tissue in the lungs, with reduced fibroblast activation and collagen deposition, and a decrease in the recruitment of the immune infiltrate. Conversely, Ptx3-null mice showed an exacerbated fibrotic response and decreased survival in response to BLM treatment. These results underline the protective role of endogenous PTX3 during lung fibrosis and pave the way for the study of novel PTX3-derived therapeutic approaches to the disease.

The Long Pentraxin 3 (PTX3) Suppresses Immunity to Cutaneous Leishmaniasis by Regulating CD4+ T Helper Cell Response

The long pentraxin 3 (PTX3) plays a critical role in inflammation, tissue repair, and wound healing. Here, we show that PTX3 regulates disease pathogenesis in cutaneous leishmaniasis (CL). PTX3 expression increases in skin lesions in patients and mice during CL, with higher expression correlating with severe disease. PTX3-deficient (PTX3^-/-) mice are highly resistant to L. major and L. braziliensis infections. This enhanced resistance is associated with increases in Th17 and IL-17A responses. The neutralization of IL-17A abolishes this enhanced resistance, while rPTX3 treatment results in decrease in Th17 and IL-17A responses and increases susceptibility. PTX3^-/- CD4⁺ T cells display increased differentiation to Th17 and expression of Th17-specific transcription factors. The addition of rPTX3 suppresses the expression of Th17 transcription factors, Th17 differentiation, and IL-17A production by CD4⁺ T cells from PTX3^-/- mice. Collectively, our results show that PTX3 contributes to the pathogenesis of CL by negatively regulating Th17 and IL-17A responses.

Soluble pattern recognition molecules: Guardians and regulators of homeostasis at airway mucosal surfaces

Maintenance of homeostasis at body barriers that are constantly challenged by microbes, toxins and potentially bioactive (macro)molecules requires complex, highly orchestrated mechanisms of protection. Recent discoveries in respiratory research have shed light on the unprecedented role of airway epithelial cells (AEC), which, besides immune cells homing to the lung, also significantly contribute to host defence by expressing membrane‐bound and soluble pattern recognition receptors (sPRR). Recent evidence suggests that distinct, evolutionary ancient, sPRR secreted by AEC might become activated by usually innocuous proteins, commonly referred to as allergens. We here provide a systematic overview on sPRR detectable in the mucus lining of AEC. Some of them become actively produced and secreted by AECs (like the pentraxins C‐reactive protein and pentraxin 3; the collectins mannose binding protein and surfactant proteins A and D; H‐ficolin; serum amyloid A; and the complement components C3 and C5). Others are elaborated by innate and adaptive immune cells such as monocytes/macrophages and T cells (like the pentraxins C‐reactive protein and pentraxin 3; L‐ficolin; serum amyloid A; and the complement components C3 and C5). Herein we discuss how sPRRs may contribute to homeostasis but sometimes also to overt disease (e.g. airway hyperreactivity and asthma) at the alveolar–air interface.

Bronchial Epithelial Cells on the Front Line to Fight Lung Infection-Causing Aspergillus fumigatus

Aspergillus fumigatus is an environmental filamentous fungus that can be pathogenic for humans, wherein it is responsible for a large variety of clinical forms ranging from allergic diseases to life-threatening disseminated infections. The contamination occurs by inhalation of conidia present in the air, and the first encounter of this fungus in the human host is most likely with the bronchial epithelial cells. Although alveolar macrophages have been widely studied in the Aspergillus–lung interaction, increasing evidence suggests that bronchial epithelium plays a key role in responding to the fungus. This review focuses on the innate immune response of the bronchial epithelial cells against A. fumigatus, the predominant pathogenic species. We have also detailed the molecular interactants and the effects of the different modes of interaction between these cells and the fungus.

Gene expression changes in human bronchial epithelial cells (BEAS-2B) and human pulmonary alveolar epithelial cells (HPAEpiC) after interaction with Cladosporium sphaerospermum

Cladosporium is one of the most abundant spore. Fungi of this genus can cause respiratory allergy and intrabronchial lesion. We studied the differential expression of host genes after the interaction of Cladosporium sphaerospermum conidia with Human Bronchial Epithelial Cells (BEAS-2B) and Human Pulmonary Alveolar Epithelial Cells (HPAEpiC). C. sphaerospermum conidia were harvested and co-cultured with BEAS-2B cells or HPAEpiC cells for 48 hours respectively. This culture duration was chosen as it was associated with high germination rate. RNA was extracted from two biological replicates per treatment. RNA of BEAS-2B cells was used to assess changes in gene expression using AffymetrixGeneChip® Human Transcriptome Array 2.0. After co-culture with Cladosporium spores, 68 individual genes were found differentially expressed (P ≤ 0.05) and up-regulated ≥ 1.5 folds while 75 genes were found differentially expressed at ≤ -1.5 folds compared with controls. Reverse transcription and qPCR were performed on the RNA collected from both BEAS-2B cells and HPAEpiC cells to validate the microarray results with 7 genes. Based on the findings, infected pulmonary epithelial cells exhibited an increase in cell death-related genes and genes associated with innate immunity.

A new scoring system for early diagnosis of ventilator-associated pneumonia: LUPPIS

INTRODUCTION

The Clinical Pulmonary Infection Score (CPIS) based on chest X-ray has been developed to facilitate clinical diagnosis of ventilator-associated pneumonia (VAP); however, this scoring system has a low diagnostic performance. We developed the Lung Ultrasound and Pentraxin-3 Pulmonary Infection Score (LUPPIS) for early diagnosis of VAP and evaluated the performance of this new scoring system.

MATERIAL AND METHODS

In a prospective study of 78 patients with suspected VAP, we assessed the detection accuracy of LUPPIS for pneumonia in adult patients. We also evaluated the diagnostic performance of pentraxin-3 (PTX-3) findings of infection. On the day of the study, lung ultrasound was performed, PTX-3 levels were determined, and an endotracheal aspirate was obtained for Gram staining and culture.

RESULTS

No significant differences were found between groups with respect to age, mechanical ventilation time, APACHE II score, or SOFA score (p > 0.05). Procalcitonin and PTX-3 levels were significantly higher in the VAP (+) group (p < 0.001 and p < 0.001, respectively). The threshold for LUPPIS in differentiating VAP (+) patients from VAP (-) patients was > 7. In predicting VAP, LUPPIS > 7 (sensitivity of 84%, specificity of 87.7%) was superior to CPIS > 6 (sensitivity of 40.1%, specificity of 84.5%).

CONCLUSIONS

LUPPIS appears to provide better results in the prediction of VAP compared to CPIS, and the importance of lung ultrasound and PTX-3 is emphasized, which is a distinctive property of LUPPIS.

Plasma PTX3, MCP1 and Ang2 are early biomarkers to evaluate the severity of sepsis and septic shock

Sepsis is associated with significant mortality. Early diagnosis and prognosis of patients with sepsis is still a difficult clinical challenge. In this study, the ability of plasma PTX3 (pentraxin 3), MCP1 (monocyte chemoattractant protein 1) and Ang (angiopoietin)1/2 was investigated to evaluate the severity of sepsis. Blood samples were obtained from 43 patients with sepsis. A total of 33 post‐surgery patients with infections and 25 healthy individuals served as controls. The results showed that plasma PTX3, MCP1 and Ang2 significantly increased in patients on the first day of septic shock onset, while sepsis patients had significantly higher Ang2 level, compared with controls. Furthermore, PTX3, MCP1 and Ang2 had high AUROC values in patients with septic shock on the first day of sepsis onset. The findings suggest that PTX3, MCP1 and Ang2 maybe early predictors to evaluate the severity of sepsis and septic shock with the latest Sepsis 3.0 definitions.

Dietary vitamin E deficiency inhibits fat metabolism, antioxidant capacity, and immune regulation of inflammatory response in genetically improved farmed tilapia (GIFT, Oreochromis niloticus) fingerlings following Streptococcus iniae infection

Vitamin E plays an important role in maintaining normal metabolism and physiological functions in animals. The health of fish fingerlings directly affects the rate of disease incidence in adult fish, and healthy fingerlings ultimately result in better breeding outcomes for cultured fish. To date, no previous studies have focused on the effects vitamin E deficiency on tilapia at the fingerling stage. In this study, we investigated the effects of dietary vitamin E on the growth, fat metabolism, antioxidant capacity, and inflammatory response of genetically improved farmed tilapia (GIFT, Oreochromis niloticus) fingerlings. Vitamin E at different concentrations (0, 20, 40, 80, 160, and 320 mg/kg) was added to the diet and GIFT were fed for 55 days. Then, the GIFT were intraperitoneally injected with Streptococcus iniae and tested for infection. Vitamin E deficiency decreased growth and increased the food conversion ratio of GIFT fingerlings. Vitamin E deficiency also reduced the white blood cell count, increased hematocrit and hemoglobin contents in the blood, increased serum aspartate aminotransferase and alanine aminotransferase activities, and increased liver stress (P < 0.05). Vitamin E deficiency inhibited fat metabolism, down-regulated the expression of genes encoding lipoprotein lipase and heart-type and liver-type fatty acid-binding proteins, and increased serum total protein and fat deposition. Vitamin E deficiency significantly decreased superoxide dismutase, glutathione peroxidase, and catalase activities, increased malondialdehyde content, and caused oxidative damage. Vitamin E deficiency also up-regulated the expression of genes encoding interleukin 1β and tumor necrosis factor α in the head kidney, and stimulated a pro-inflammatory response. Overall, vitamin E deficiency inhibited growth, impaired fat metabolism, and disrupted the inflammatory response of GIFT fingerlings, whereas vitamin E supplementation in the diet reversed these negative effects. The diets with high concentrations of vitamin E (160-320 mg/kg) led to vitamin E accumulation in the fish tissues and rapid activation of the inflammatory response and antioxidant capacity in GIFT fingerlings exposed to S. iniae.

Glucocorticoids regulate pentraxin-3 expression in human airway smooth muscle cells

Pentraxin-3 (PTX3) is a multifunctional protein involved in both innate and adaptive immunity. Glucocorticoid (GC) is the first-line therapy to mitigate airway inflammation in asthma. Previous pieces of evidence showed that GC has divergent effects on PTX3 production in various cell types. The molecular mechanisms controlling PTX3 expression in HASMC are, however, not yet characterized. In this study, we demonstrate that the synthetic GC, dexamethasone (DEX) increases the expression of PTX3 both at the protein and mRNA levels. We also found that such an effect of DEX was dependent on de novo protein synthesis and the GC receptor (GR). While DEX increases PTX3 mRNA stability, it did not affect its promoter activity. Interestingly, HASMC pre-treated with p42/p44 ERK inhibitor, but not with p38 or JNK-MAPK inhibitors, significantly interfered with DEX-induced PTX3 secretion. Taken together, our data suggest that GC regulates PTX3 expression in HASMC through transcriptional and post-transcriptional mechanisms in a GR and ERK-dependent manner.

Elevated Neuropeptide Y in Endothelial Dysfunction Promotes Macrophage Infiltration and Smooth Muscle Foam Cell Formation

Endothelial dysfunction has been linked to vascular inflammation and foam cell formation but the underlying mechanisms still remain unclear. We sought to define the factors inducing inflammation and smooth muscle foam cell formation under endothelial dysfunction using endothelial nitric oxide synthase (eNOS)-deficient mice. Vascular smooth muscle cells (VSMCs) from eNOS-deficient mice displayed increased expression of macrophage-related genes and elevated lipid uptake. Neuropeptide Y (NPY) was upregulated in the aorta from the eNOS-deficient mice and promoted macrophage chemotaxis toward VSMCs while enhancing the activity of matrix metalloproteinase-3. Notably, NPY induced lipid uptake in VSMCs, facilitating smooth muscle foam cell formation, in association with enhanced expression of genes related to modified low-density lipoprotein uptake and macrophages. NPY was augmented by inflammatory pentraxin 3 (PTX3) in VSMCs. PTX3 enhanced macrophage migratory capacity through the NPY/neuropeptide Y receptor axis and this effect was attenuated by pharmacological inhibition with a receptor-specific antagonist. These observations suggest that endothelial dysfunction leads to the elevation of NPY that amplifies vascular inflammation by increasing inflammatory cell chemotaxis and triggers smooth muscle foam cell formation.

Quercetin reduces TNF-α-induced mesangial cell proliferation and inhibits PTX3 production: Involvement of NF-κB signaling pathway

Lupus nephritis (LN) is an autoimmune disease caused by systemic lupus erythematosus. Excessive proliferation of mesangial cells is one of the most serious pathological manifestations of LN. In addition, the expression of PTX3 is elevated in the serum of patients with LN. Quercetin has good anti-inflammatory effects and immunomodulatory activities. In this study, the result of MTT indicated that quercetin treatment alleviated the excessive proliferation of mesangial cells. ELISA and immunofluorescence experiments showed that quercetin treatment inhibited the expression of PTX3. Three doses of quercetin (20, 40, and 80 μM) were selected for the experiment. It is noteworthy that the efficacy of quercetin at 80 μM was significantly better than that of other dose groups. And the effect in inhibiting PTX3 expression was comparable with that of the PDTC (80 μM) positive control. Western blot and qRT-PCR analysis revealed that quercetin treatment reduced the expression of nuclear factor-κB p65 and IKKβ, increased the expression of IκBα, and inhibited the expression of PTX3. In conclusion, through inhibiting the activation of nuclear factor-κB signaling pathway, quercetin treatment could reduce the expression of PTX3 and inhibit the excessive proliferation of mesangial cells, suggesting that quercetin is a potential therapeutic drug for LN.

Pentraxin 3 deficiency exacerbates lipopolysaccharide-induced inflammation in adipose tissue

BACKGROUND/OBJECTIVES

Pentraxin 3 (PTX3) has been characterized as a soluble and multifunctional pattern recognition protein in the regulation of innate immune response. However, little is known about its role in adipose tissue inflammation and obesity. Herein, we investigated the role of PTX3 in the regulation of lipopolysaccharide (LPS)-induced inflammation in adipocytes and adipose tissue, as well as high-fat diet (HFD)-induced metabolic inflammation in obesity.

METHODS

Ptx3 knockdown 3T3-L1 Cells were generated using shRNA for Ptx3 gene and treated with different inflammatory stimuli. For the in vivo studies, Ptx3 knockout mice were treated with 0.3 mg/kg of LPS for 6 h. Adipose tissues were collected for gene and protein expression by qPCR and western blotting, respectively. Ptx3 knockout mice were fed with HFD for 12 week since 6 week of age.

RESULTS

We observed that the expression of PTX3 in adipose tissue and serum PTX3 were markedly increased in response to LPS administration. Knocking down Ptx3 in 3T3-L1 cells reduced adipogenesis and caused a more profound and sustained upregulation of proinflammatory gene expression and signaling pathway activation during LPS-stimulated inflammation in 3T3-L1 adipocytes. In vivo studies showed that PTX3 deficiency significantly exacerbated the LPS-induced upregulation of inflammatory genes and downregulation of adipogeneic genes in visceral and subcutaneous adipose tissue of mice. Accordingly, LPS stimulation elicited increased activation of nuclear factor-κB (NF-κB) and p44/42 MAPK (Erk1/2) signaling pathways in visceral and subcutaneous adipose tissue. The expression of PTX3 in adipose tissue was also induced by HFD, and PTX3 deficiency led to the upregulation of proinflammatory genes in visceral adipose tissue of HFD-induced obese mice.

CONCLUSIONS

Our results suggest a protective role of PTX3 in LPS- and HFD-induced sustained inflammation in adipose tissue.

Innate immunity, inflammation and tumour progression: double-edged swords

Components of the cellular and the humoral arm of the immune system are essential elements of the tumour microenvironment (TME). The TME includes tumour-associated macrophages which have served as a paradigm for the cancer-promoting inflammation. Cytokines, IL-1 in particular, and complement have emerged as important players in tumour promotion. On the other hand, myeloid cells, innate lymphoid cells and complement have the potential, if unleashed, to mediate anticancer resistance. Targeting checkpoints restraining innate immunity, macrophages and natural killer (NK) cells in particular holds promise as a therapeutic strategy.

The Long Pentraxin PTX3 as a Link Between Innate Immunity, Tissue Remodeling, and Cancer

The innate immune system comprises a cellular and a humoral arm. Humoral pattern recognition molecules include complement components, collectins, ficolins, and pentraxins. These molecules are involved in innate immune responses by recognizing microbial moieties and damaged tissues, activating complement, exerting opsonic activity and facilitating phagocytosis, and regulating inflammation. The long pentraxin PTX3 is a prototypic humoral pattern recognition molecule that, in addition to providing defense against infectious agents, plays several functions in tissue repair and regulation of cancer-related inflammation. Characterization of the PTX3 molecular structure and biochemical properties, and insights into its interactome and multiple roles in tissue damage and remodeling support the view that microbial and matrix recognition are evolutionarily conserved functions of humoral innate immunity molecules.

Pentraxin-3 and inflammatory biomarkers related to posterolateral thoracotomy in Thoracic Surgery

Objective:

Posterolateral thoracotomy is the most frequently used operation in thoracic surgery, and may initiate an inflammatory process. We aimed to evaluate inflammatory response of the body to posterolateral thoracotomy.

Methods:

This study was conducted between January 2013 and June 2014. Blood samples were drawn from 36 patients who underwent posterolateral thoracotomy preoperatively, and on postoperative days one, three and seven The levels of PTX-3, CRP and WBC in the serums of the patients were identified. All the results were recorded and analyzed.

Results:

PTX-3 levels were found statistically significantly higher in patients with lung cancer and/or aged above 65 years. There were significant differences in WBC and CRP levels between preoperative levels and on those on postoperative days one, three and seven but not for PTX-3. The area under the curve(AUC) levels in the receiver operating characteristics(ROC) analysis, which was performed to estimate the strength of PTX-3 in the differentiation of malignant and benign patients was found statistically significant(p<0.05).

Conclusions:

The present study suggests that the novel inflammatory marker PTX-3 may be used in the diagnosis and follow-up of prognosis as a biomarker of inflammatory response in patients with lung cancer. However, it showed that PTX-3 levels are insignificant to identify the levels of inflamatuar response due to posterolateral thoracotomy in thoracic surgery.

Source of Circulating Pentraxin 3 in Septic Shock Patients

Sepsis, which is the leading cause of death in intensive care units (ICU), has been acknowledged as a global health priority by the WHO in 2017. Identification of biomarkers allowing early stratification and recognition of patients at higher risk of death is crucial. One promising biomarker candidate is pentraxin-3 (PTX3); initially elevated and persistently increased plasma concentration in septic patients has been associated with increased mortality. PTX3 is an acute phase protein mainly stored in neutrophil granules. These cells are responsible for rapid and prompt release of PTX3 in inflammatory context, but the cellular origin responsible for successive days' elevation in sepsis remains unknown. Upon inflammatory stimulation, PTX3 can also be produced by other cell types, including endothelial and immune cells. As in septic patients immune alterations have been described, we therefore sought to investigate whether such cells participated in the elevation of PTX3 over the first days after septic shock onset. To address this point, PTX3 was measured in plasma from septic shock patients at day 3 after ICU admission as well as in healthy volunteers (HV), and the capacity of whole blood cells to secrete PTX3 after inflammatory stimulation was evaluated ex vivo. A significantly mean higher (100-fold) concentration of plasma PTX3 was found in patients compared to HV, which was likely due to the inflammation-induced initial release of the pre-existing PTX3 reservoir contained in neutrophils. Strikingly, when whole blood was stimulated ex vivo with LPS no significant difference between patients and HV in PTX3 release was found. This was in contrast with TNFα which decreased production was illustrative of the endotoxin tolerance phenomenon occurring in septic patients. Then, the release of PTX3 protein from a HV neutrophil-free PBMC endotoxin tolerance model was investigated. At the transcriptional level, PTX3 seems to be a weakly tolerizable gene similar to TNFα. Conversely, increased protein levels observed in anergy condition reflects a non-tolerizable phenotype, more likely to an anti-inflammatory marker. Hence, altered immune cells still have the ability to produce PTX3 in response to an inflammatory trigger, and therefore circulating white blood cell subset could be responsible of the sustained PTX3 plasma levels over the first days of sepsis setting.

Role of a fluid-phase PRR in fighting an intracellular pathogen: PTX3 in Shigella infection

Shigella spp. are pathogenic bacteria that cause bacillary dysentery in humans by invading the colonic and rectal mucosa where they induce dramatic inflammation. Here, we have analyzed the role of the soluble PRR Pentraxin 3 (PTX3), a key component of the humoral arm of innate immunity. Mice that had been intranasally infected with S. flexneri were rescued from death by treatment with recombinant PTX3. In vitro PTX3 exerts the antibacterial activity against Shigella, impairing epithelial cell invasion and contributing to the bactericidal activity of serum.

PTX3 is produced upon LPS-TLR4 stimulation in accordance with the lipid A structure of Shigella. In the plasma of infected patients, the level of PTX3 amount only correlates strongly with symptom severity. These results signal PTX3 as a novel player in Shigella pathogenesis and its potential role in fighting shigellosis. Finally, we suggest that the plasma level of PTX3 in shigellosis patients could act as a biomarker for infection severity.

Soluble pattern recognition molecules, PRMs, are components of the humoral arm of innate immunity. The long pentraxin 3, PTX3, is a prototypic soluble PRM that is produced in response to primary inflammatory signals. Shigella spp. are human entero-pathogens which invade colonic and rectal mucosa where they cause deleterious inflammation. We show that PTX3 acts as an ante-antibody and contributes to the clearance of extracellular Shigella. As a countermeasure, Shigella uses invasiveness and low-inflammatory LPS to control PTX3 release in infected cells. This study highlights that the extracellular phase of the invasion process can be considered the “Achille heels” of Shigella pathogenesis.

Identification of DKK-1 as a novel mediator of statin effects in human endothelial cells

This study shows that DKK-1, a member of the Dickkopf family and a regulator of the Wnt pathways, represents a novel target of statins which, through the inhibition of HMG-CoA reductase and of non-steroidal isoprenoid intermediates, exert extra-beneficial effect in preventing atherosclerosis beyond their effect on the lipid profile. We found that atorvastatin downregulates DKK-1 protein (−88.3 ± 4.1%) and mRNA expression (−90 ± 4.2%) through the inhibition of Cdc42, Rho and Rac geranylgeranylated proteins. Further, a combined approach based on the integration of label-free quantitative mass spectrometry based-proteomics and gene silencing allowed us to demonstrate that DKK-1 itself mediates, at least in part, statin effects on human endothelial cells. Indeed, DKK-1 is responsible for the regulation of the 21% of the statin-modulated proteins, which include, among others, clusterin/apoJ, plasminogen activator inhibitor type 1 (PAI-1), myristoylated alanine-rich C-kinase substrate (MARCKS), and pentraxin 3 (PTX3). The Gene Ontology enrichment annotation revealed that DKK-1 is also a potential mediator of the extracellular matrix organization, platelet activation and response to wounding processes induced by statin. Finally, we found that plasma level of DKK-1 from cholesterol-fed rabbits treated with atorvastatin (2.5 mg/kg/day for 8 weeks) was lower (−42 ± 23%) than that of control animals. Thus, DKK-1 is not only a target of statin but it directly regulates the expression of molecules involved in a plethora of biological functions, thus expanding its role, which has been so far restricted mainly to cancer.

PTX3, a Humoral Pattern Recognition Molecule, in Innate Immunity, Tissue Repair, and Cancer

Innate immunity includes a cellular and a humoral arm. PTX3 is a fluid-phase pattern recognition molecule conserved in evolution which acts as a key component of humoral innate immunity in infections of fungal, bacterial, and viral origin. PTX3 binds conserved microbial structures and self-components under conditions of inflammation and activates effector functions (complement, phagocytosis). Moreover, it has a complex regulatory role in inflammation, such as ischemia/reperfusion injury and cancer-related inflammation, as well as in extracellular matrix organization and remodeling, with profound implications in physiology and pathology. Finally, PTX3 acts as an extrinsic oncosuppressor gene by taming tumor-promoting inflammation in murine and selected human tumors. Thus evidence suggests that PTX3 is a key homeostatic component at the crossroad of innate immunity, inflammation, tissue repair, and cancer. Dissecting the complexity of PTX3 pathophysiology and human genetics paves the way to diagnostic and therapeutic exploitation.

Early expression of PTX3 in Aspergillus fumigatus infected rat cornea

AIM

To investigate the expression of pentraxin 3 (PTX3) in rat corneal epithelium at the early stage of Aspergillus fumigatus (A. fumigatus) infection.

METHODS

A total of 50 Wistar rats were randomly divided into control group, Sham group and experimental group (fungal keratitis group, FK group). The right eye was chosen as the experiment one and infected by A. fumigatus. Rats were executed at 8, 16 and 24h after the experimental models being established. Corneal epithelia were collected to assess the expression of PTX3 by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot analysis.

RESULTS

Corneal inflammation scores increased as infection prolonged (P<0.05, P<0.001). PTX3 mRNA expression was low in normal and Sham group rats' corneas. Level of PTX3 mRNA in infected rat cornea was elevated at 8h and peaked at 16h. The difference was significant compared with control group (P<0.001). Western blot analysis also showed a significant increase of PTX3 protein in experimental group at 8h and peaked at 16h (P<0.001). The synchronous expression of control group and experimental group were also in significant difference (P<0.001).

CONCLUSION

PTX3 exists in cornea epithelium and is significantly increased after A. fumigatus infection. PTX3 plays an important role in the early stage of cornea innate immunity against A. fumigatus.

Prenatal Exposure to Lipopolysaccharide Induces PTX3 Expression and Results in Obesity in Mouse Offspring

This study tested the hypothesis whether inflammation will directly lead to obesity. This study was designed to investigate the relationship between inflammation and obesity by intraperitoneally injecting pregnant mice with lipopolysaccharide (LPS) (75 μg kg^-1). The results showed that inflammation during pregnancy could lead to a significant increase in the levels of the inflammatory factor PTX3. The offspring of the LPS-treated mice displayed abnormal levels of fat development, blood lipids, and glucose metabolism, and fat differentiation markers were significantly increased. Our study also confirmed that PTX3 can increase the susceptibility to obesity by regulating the expression of adipogenic markers; this regulatory role of PTX3 is most likely caused by MAPK pathway hyperactivation. Our study is the first to find strong evidence of inflammation as a cause of obesity. We determined that PTX3 was an important moderator of obesity, and we elucidated its mechanism, thus providing new targets and theories for obesity therapy. Moreover, our study provides new ideas and directions for the early intervention of anti-inflammation in pregnancy.

Genetic characterization of indigenous goat breeds in Romania and Hungary with a special focus on genetic resistance to mastitis and gastrointestinal parasitism based on 40 SNPs

Goat breeding has become an important sector in Eastern Europe, with Romania and Hungary being among the major producer countries. Given the limited number of research done up-to-date concerning genetic studies of indigenous goat breeds reared in Romania and Hungary, the current preliminary study aimed to analyze the variability of genes related to mastitis and gastrointestinal parasitism by using Kompetitive Allele Specific PCR (KASP™). We studied 52 single nucleotide polymorphisms (SNPs) belonging to 19 genes in indigenous breeds from both countries, namely Banat's White (n = 36), Carpatina (n = 35) from Romania and Hungarian Milking (n = 79) and identified 16 polymorphic SNPs among 10 genes (PTX3, IL6, CLEC4E, IL8, IL1RN, IL15RA, TNFSF13, SOCS3, TNF and TLR3) in 150 animals. Furthermore, the diversity of the studied breeds was investigated. The PIC values ranged from 0.042 to 0.691. The mean values of observed and expected heterozygosity were 0.235 and 0.246 respectively. The highest observed heterozygosity was obtained for IL15RA g.10343904C>T in Banat's White (0.464), IL15RA g.10354813C>T in Carpatina (0.577) and SOCS3 g.52626440T>G in Hungarian Milking (0.588). Pairwise FST values between the Romanian breeds and Romanian and Hungarian breeds were small (0.009 and 0.015), indicating the close relationship among the studied goat populations. From all the polymorphic SNPs identified, the Hungarian Milking breed showed the highest proportion of polymorphisms (100%), whereas the Carpatina breed had the lowest percentage (87.5%). The highest value of MAF was obtained for SOCS3 g.52626440T>G (0.46), IL15RA g.10343904C>T (0.47), IL15RA g.10344025C>T (0.45), and IL15RA g.10354813C>T (0.42). The 16 polymorphic SNPs identified in a panel of 150 unrelated individuals belonging to three Romanian and Hungarian indigenous goat breeds could be used in future genomic based breeding schemes as markers for genetic resistance to mastitis and gastrointestinal parasitism in goat breeds found in Eastern and Central Europe.

Serum levels of Pentraxin 3 differ significantly at the time of blastocyst transfer depending on implantation success: a pilot study

OBJECTIVE

Many approaches try to identify the underlying molecular mechanisms to detect new potential biomarkers for successful artificial reproductive therapies. One factor has been described as a possible regulator of inflammation during implantation: Pentraxin 3 (PTX3), which seems to be essential for female fertility on one hand, but whose overexpression has been described in many obstetric complications based on abnormal placentation on the other hand. Therefore, we investigated if serum levels of PTX3 at the time of embryo transfer differ between women with an ongoing pregnancy compared to those without implantation.

METHODS/DESIGN

During in vitro fertilization cycles of 51 patients, PTX3 levels at the time of embryo transfer were compared between patients without implantation (n = 26) and those with ongoing pregnancy (n = 25) using an enzyme-linked immunosorbent assay. Statistical analysis was performed using the Kolmogorov-Smirnov test, Fisher's exact test and Student's t test RESULTS: No significant differences were found concerning possible confounders (patients age, smoking pattern, embryo quality, number of embryos transferred and prior IVF attempts). Patients without implantation presented with significantly higher serum levels of PTX3 at the time of embryo transfer compared to women who became pregnant (0.781 ± 0.074 ng/ml vs. 0.578 ± 0.055 ng/ml, p < 0.05).

CONCLUSIONS

PTX3 could present as a possible biomarker for ART success. The main limitation of this pilot study is its small sample size that needs validation with a larger study population.

Long pentraxin 3: A novel multifaceted player in cancer

Since its discovery in 1992, long pentraxin 3 (PTX3) has been characterized as soluble patter recognition receptor, a key player of the innate immunity arm with non-redundant functions in pathogen recognition and inflammatory responses. As a component of the extra-cellular matrix milieu, PTX3 has been implicated also in wound healing/tissue remodeling, cardiovascular diseases, fertility, and infectious diseases. Consequently, PTX3 levels in biological fluids have been proposed as a fluid-phase biomarker in different pathological conditions. In the last decade, experimental evidences have shown that PTX3 may exert a significant impact also on different aspects of cancer biology, including tumor onset, angiogenesis, metastatic dissemination and immune-modulation. However, it remains unclear whether PTX3 acts as a good cop or bad cop in cancer. In this review, we will summarize and discuss the scientific literature data focusing on the role of PTX3 in experimental and human tumors, including its putative translational implications.

Acute ethanol intoxication suppresses pentraxin 3 expression in a mouse sepsis model involving cecal ligation and puncture

Acute ethanol intoxication impairs immunological reactions and increases the risk of sepsis; however, the underlying mechanism remains unclear. Pentraxin (PTX) 3 is a humoral pattern recognition receptor whose levels rapidly increase in response to inflammation. PTX3 production is triggered by tumor necrosis factor (TNF)-α and is mediated by c-Jun N-terminal kinase (JNK). As PTX3 exerts protective effects against sepsis as well as acute lung injury, we investigated whether acute ethanol exposure exacerbates sepsis by altering PTX3 expression. Sepsis was induced in C57/BL6 mice by cecal ligation and puncture (CLP) after ethanol/saline administration. Survival rates were significantly lower in ethanol-treated than in saline-treated mice. Increased vascular permeability and attenuation of PTX3 expression were observed in the lungs of ethanol-treated mice 4 h after CLP. Concomitant with a delayed increase of plasma TNF-α in ethanol-treated mice, plasma PTX3 was also suppressed in the early phase of sepsis. Although TNF-α level in ethanol-treated mice exceeded that in saline-treated mice 16 h after CLP, PTX3 levels were still suppressed in the former group. JNK phosphorylation in lung tissue was suppressed in both groups 4 and 16 h after CLP. Furthermore, JNK phosphorylation in ethanol-treated human umbilical vein endothelial cells was suppressed even in the presence of exogenous TNF-α, resulting in inhibition of PTX3 mRNA and protein expression. Our results suggest that ethanol suppresses de novo PTX3 synthesis via two mechanisms - i.e., suppression of TNF-α production and inhibition of JNK phosphorylation. PTX3 suppression may therefore contribute to exacerbation of sepsis in acute ethanol intoxication.

Long pentraxin PTX3 mediates acute inflammatory responses against pneumococcal infection

Streptococcus pneumoniae is an important human pathogen responsible for more than 2 million deaths annually worldwide. The airway epithelium acts as the first-line of defense against pneumococcal infections by regulating acute inflammation against invading pneumococcus. Despite the intact adaptive immunity, failure in early defense due to loss of pattern recognition receptors (PRRs) and/or acute phase proteins (APPs) results in detrimental damage and death. C-reactive protein (CRP), the first found APP, is a member of the pentraxin family of proteins and an important soluble PRR for pneumococcus. CRP and another short pentraxin, serum amyloid P, are critical for acute defense against pneumococcal infection. However, the role of the long pentraxin PTX3 in regulating pneumococcal infections is unknown. In this study, PTX3 expression was upregulated by pneumococcus in epithelial cells and in lungs of mice. In addition, PTX3 potentiated pneumococcal inflammation; overexpression of PTX3 enhanced pneumococcus-induced cytokine expression, whereas knock-down of PTX3 with siPTX3 inhibited the cytokine expression. Furthermore, PTX3 deficiency indeed ameliorated acute inflammation and protected mice against death following pneumococcal infection. Pneumococcal toxin pneumolysin was responsible for PTX3 expression and upregulated PTX3 expression via JNK MAPK signaling. These data implicate PTX3 as a novel therapeutic target for the control of acute inflammation by pneumococcus.

C-Reactive Protein Binds to Cholesterol Crystals and Co-Localizes with the Terminal Complement Complex in Human Atherosclerotic Plaques

Inflammation is a part of the initial process leading to atherosclerosis and cholesterol crystals (CC), found in atherosclerotic plaques, which are known to induce complement activation. The pentraxins C-reactive protein (CRP), long pentraxin 3 (PTX3), and serum amyloid P component (SAP) are serum proteins associated with increased risk of cardiovascular events and these proteins have been shown to interact with the complement system. Whether the pentraxins binds to CC and mediate downstream complement-dependent inflammatory processes remains unknown. Binding of CRP, PTX3, and SAP to CC was investigated in vitro by flow cytometry and fluorescence microscopy. CRP, PTX3, and SAP bound to CC in a concentration-dependent manner. CRP and PTX3 interacted with the complement pattern recognition molecule C1q on CC by increasing the binding of both purified C1q and C1q in plasma. However, CRP was the strongest mediator of C1q binding and also the pentraxin that most potently elevated C1q-mediated complement activation. In a phagocytic assay using whole blood, we confirmed that phagocytosis of CC is complement dependent and initiated by C1q-mediated activation. The pathophysiological relevance of the in vitro observations was examined in vivo in human atherosclerotic plaques. CRP, PTX3, and SAP were all found in atherosclerotic plaques and were located mainly in the cholesterol-rich necrotic core, but co-localization with the terminal C5b-9 complement complex was only found for CRP. In conclusion, this study identifies CRP as a strong C1q recruiter and complement facilitator on CC, which may be highly relevant for the development of atherosclerosis.

Pseudomonas aeruginosa GroEL Stimulates Production of PTX3 by Activating the NF-κB Pathway and Simultaneously Downregulating MicroRNA-9

As one of the first lines of host defense, monocytes play important roles in clearing infected microbes. The defensive response is triggered by recognition of diverse microbial moieties, including released factors, which modulate host immune responses to establish a harsh environment for clinically important bacterial pathogens. In this study, we found that the expression of PTX3, a soluble form of pattern recognition receptor, was induced by infection with live Pseudomonas aeruginosa or treatment of cells with its supernatant. P. aeruginosa GroEL, a homolog of heat shock protein 60, was identified as one of the factors responsible for inducing the expression of PTX3 in host cells. GroEL induced PTX3 expression by activating the Toll-like receptor 4 (TLR4)-dependent pathway via nuclear factor-kappa B (NF-κB), while simultaneously inhibiting expression of microRNA-9, which targets the PTX3 transcript. Finally, by acting as an opsonin, GroEL-induced PTX3 promoted the association and phagocytosis of Staphylococcus aureus into macrophages. These data suggest that the host defensive environment is supported by the production of PTX3 in response to GroEL, which thus has therapeutic potential for clearance of bacterial infections.

Particulate matter-mediated release of long pentraxin 3 (PTX3) and vascular endothelial growth factor (VEGF) in vitro: Limited importance of endotoxin and organic content

Exposure to particulate matter (PM) is associated with adverse health effects, but it is still relatively unknown which role PM sources and physicochemical properties play in the observed effects. It was postulated that PM in vitro induces release of long pentraxin 3 (PTX3) and vascular endothelial growth factor (VEGF) and that endotoxin and organic compounds present in the PM regulate this release. A contact coculture of THP-1 human leukemia monocytes and A549 human adenocarcinoma alveolar pneumocytes was exposed to PM from Traffic, Wood, Diesel, and Quartz (10-40 µg/cm²) for 12-64 h to determine release of PTX3 and VEGF. The role of endotoxin and the organic fraction in the mediator release was assessed using polymyxin B sulfate and organic extracts, respectively. Finally, antagonists were used to investigate whether the early proinflammatory cytokines interleukin (IL)-1 and tumor necrosis factor (TNF)-α affected the PTX3 and VEGF release. All PM samples induced a time-dependent release of both PTX3 and VEGF. Traffic mediated the greatest release of PTX3, whereas Wood and Diesel were more potent inducers of VEGF. The endotoxin content did not markedly affect release of either mediator, while the organic fraction exerted no significant effect on VEGF release and limited influence on PTX3 release. In addition, the IL-1 and TNF-α agonists affected PTX3 release more strongly than VEGF release. In conclusion, the current data show a limited impact of endotoxin and organic compounds on PTX3 and VEGF release. Further, the observed differences in response patterns may point toward differential regulation of PM-mediated release of PTX3 and VEGF.

Role of PTX3 in corneal epithelial innate immunity against Aspergillus fumigatus infection

Pentraxin3 (PTX3), a member of long pentraxin family, plays a non-redundant role in human humoral innate immunity. However, whether PTX3 is expressed by corneal epithelial cells and its role during corneal fungi infection has not yet been investigated. To identify the presence of PTX3 in cornea, the possible mechanisms involved in its expression, and also the effects on corneal anti-fungi innate immune response, clinic human corneal tissues and cultured human corneal epithelial cells (HCECs) were resorted. PTX3 mRNA and protein were detected in corneal samples and cultured HCECs, which was significantly up-regulated after exposing to Aspergillus fumigatus (A. fumigatus). Pretreated with specific inhibitors, only Syk contributed to the regulation of PTX3 expression in Dectin-1/Syk signal axis. Furthermore, among the MAPK members (p38 MAPK, ERK1/2 and JNK), only ERK1/2 and JNK were responsible for A. fumigatus induced PTX3 production. Blocking of endogenous PTX3 by siRNA down-regulated the production of IL-1β at both mRNA and protein levels. Meanwhile, blocking of PTX3 also inhibited the phosphorylation of ERK1/2 and JNK, but not p38 MAPK. These findings demonstrate that PTX3 is expressed in human corneal epithelial cells and Syk, ERK1/2, JNK signaling pathways play an important role in the regulation of PTX3 induction. PTX3 plays a proinflammatory role in corneal epithelial anti-fungi immune response by affecting the production of IL-1β and activation of some proinflammatory signaling pathways (ERK1/2 and JNK).

Innate immunity, hemostasis and matrix remodeling: PTX3 as a link

Innate immunity is evolutionarily connected with hemostasis. PTX3 is an essential fluid-phase pattern recognition molecule of the innate immune system that acts as a functional ancestor of antibodies. PTX3 by interacting with defense collagens and fibrinogens amplifies effector functions of the innate immune system. At wound sites, PTX3 regulates the injury-induced thrombotic response and promotes wound healing by favoring timely fibrinolysis. Therefore, PTX3 interacts with ancestral domains conserved in innate immunity, hemostasis and extracellular matrix and exerts functions related to both antimicrobial resistance and tissue repair. These findings strengthen the connection between innate immune system and hemostasis, and suggest that recognition of microbes and extracellular matrix are evolutionarily conserved and integrated functions of the innate immune system.

Three pentraxins C-reactive protein, serum amyloid p component and pentraxin 3 mediate complement activation using Collectin CL-P1

BACKGROUND

Pentraxins (PTXs) are a superfamily of multifunctional conserved proteins involved in acute-phase responses. Recently, we have shown that collectin placenta 1 (CL-P1) and C-reactive protein (CRP) mediated complement activation and failed to form terminal complement complex (TCC) in normal serum conditions because of complement factor H inhibition.

METHODS

We used CL-P1 expressing CHO/ldlA7 cells to study the interaction with PTXs. Soluble type CL-P1 was used in an ELISA assay for the binding, C3 and TCC deposition experiments. Furthermore, we used our previously established CL-P1 expressing HEK293 cells for the C3 fragment and TCC deposition assay.

RESULTS

We demonstrated that CL-P1 also bound serum amyloid p component (SAP) and pentraxin 3 (PTX3) to activate the classical pathway and the alternative pathway using factor B. CRP and PTX3 further amplified complement deposition by properdin. We found that CRP and PTX3 recruit CFH, whereas SAP recruits C4 binding protein on CL-P1 expressing cell surfaces to prevent the formation of TCC in normal serum conditions. In addition, depletion of CFH, C4BP and complement factor I (CFI) failed to prevent TCC formation both in ELISA and cell experiments. Furthermore, soluble complement receptor 1, an inhibitor of all complement pathways prevents PTX induced TCC formation.

CONCLUSION

Our current study hypothesizes that the interaction of pentraxins with CL-P1 is involved in complement activation.

GENERAL SIGNIFICANCE

CL-P1 might generally inhibit PTX induced complement activation and host damage to protect self-tissues.

Pentraxin-3 levels in graft-versus-host disease during allogeneic hematopoietic stem cell transplantation

Acute and chronic graft-versus-host-diseases (aGVHD and cGVHD, respectively) are serious complications after hematopoietic stem cell transplantation (HSCT), impairing survival and quality of life. Because the underlying pathomechanism of GVHD is still poorly understood, we investigated the novel inflammatory marker Pentraxin-3 (PTX3) for its potential role in acute and chronic GVHD compared with autologous HSCT and healthy individuals. We collected plasma samples from patients undergoing autologous (n = 12) and allogeneic (n = 28) HSCT and from healthy individuals (n = 15) throughout 7 days before and up to 1 year after HSCT. PTX3 levels in patients with aGVHD were significantly higher (36.4 ± 23.6 ng/mL) than in allogeneic patients without aGVHD (10.4 ± 4.4 ng/mL, p = 0.0001), autologous controls (11.4 ± 6.7 ng/mL, p = 0.001), or healthy individuals (1.9 ± 0.6 ng/mL, p < 0.001). PTX3 levels in patients with cGVHD (13.6 ± 6.3 ng/mL) were significantly lower than in allogeneic patients without cGVHD (25.1 ± 13.8 ng/mL, p = 0.04) and higher than in autologous controls (8.9 ± 7.8 ng/mL, p = 0.07) and healthy individuals (1.9 ± 0.6 ng/mL, p < 0.001). Severity of aGVHD and cGVHD correlated with PTX3 levels. Rising PTX3 levels after HSCT indicated unfavorable outcome. We show that PTX3 levels correlate with the severity of aGVHD, cGVHD, and-with reservations-survival in patients undergoing allogeneic HSCT.

Interactions of Aspergillus fumigatus Conidia with Airway Epithelial Cells: A Critical Review

Aspergillus fumigatus is an environmental filamentous fungus that also acts as an opportunistic pathogen able to cause a variety of symptoms, from an allergic response to a life-threatening disseminated fungal infection. The infectious agents are inhaled conidia whose first point of contact is most likely to be an airway epithelial cell (AEC). The interaction between epithelial cells and conidia is multifaceted and complex, and has implications for later steps in pathogenesis. Increasing evidence has demonstrated a key role for the airway epithelium in the response to respiratory pathogens, particularly at early stages of infection; therefore, elucidating the early stages of interaction of conidia with AECs is essential to understand the establishment of infection in cohorts of at-risk patients. Here, we present a comprehensive review of the early interactions between A. fumigatus and AECs, including bronchial and alveolar epithelial cells. We describe mechanisms of adhesion, internalization of conidia by AECs, the immune response of AECs, as well as the role of fungal virulence factors, and patterns of fungal gene expression characteristic of early infection. A clear understanding of the mechanisms involved in the early establishment of infection by A. fumigatus could point to novel targets for therapy and prophylaxis.