Systemic inflammation and antibodies to citrullinated peptides in hand osteoarthritis.

OBJECTIVES: To investigate systemic inflammation and autoimmune response to citrullinated peptides in patients with erosive and non erosive 'lone' hand osteoarthritis (HOA) with no hip/knee involvement and their relationship with radiographic structural damage. METHODS: Sera were obtained from a total of 99 patients with HOA (52 patients with erosive HOA and 47 patients with non-erosive HOA) and from 50 control subjects (NC). Hand radiographs were obtained from all patients and scored for joint damage according to the Kellgren-Lawrence and the Kallman scores. Serum levels of high-sensitivity CRP (hsCRP), IL-6, pentraxin-3 (PTX-3), anti-CCP and anti-modified citrullinated vimentin (MCV) antibodies were evaluated by a sandwich ELISA. RESULTS: Circulating levels of inflammatory biomarkers hsCRP, IL-6 and PTX3 were not significantly different in the two groups of patients with erosive and non-erosive HOA compared to NC and no significant difference was seen between non-erosive and erosive HOA. Anti-CCP positivity was detected respectively in 1 patient (2.1%) with non-erosive HOA and 1 patient (1.9%) with erosive HOA. Anti-MCV antibodies were present in 4 patients (8.5%) with non-erosive HOA, and 4 patients (7.7%) with erosive HOA. In the control group, one subject (2%) was positive for anti-CCP and 2 subjects (4%) had anti-MCV antibodies. Significant correlation was obtained only between body mass index and hsCRP concentration (r=0.4071; p<0.0001). No correlation between inflammation markers/autoantibodies and disease duration and radiological scores was found. CONCLUSIONS: Our study underlines the lack of systemic inflammation and autoimmunity in 'lone' HOA and confirms the association between BMI and CRP levels.

Dexamethasone prophylaxis in pediatric open heart surgery is associated with increased blood long pentraxin PTX3: potential clinical implications.

Glucocorticoid administration before cardiopulmonary bypass (CPB) can reduce the systemic inflammatory response and improve clinical outcome. Long pentraxin PTX3 is a novel inflammatory parameter that could play a protective cardiovascular role by regulating inflammation. Twenty-nine children undergoing open heart surgery were enrolled in the study. Fourteen received dexamethasone (1st dose 1.5 mg/Kg i.v. or i.m. the evening before surgery; 2nd dose 1.5 mg/kg i.v. before starting bypass) and fifteen children served as control. Blood PTX3, short pentraxin C-reactive protein (CRP), interleukin-1 receptor II (IL-1RII), fibrinogen and partial thromboplastin time (PTT) were assayed at different times. PTX3 levels significantly increased during CPB in dexamethasone-treated (+D) and dexamethasone-untreated (-D) subjects, but were significantly higher in +D than -D patients. CRP levels significantly increased both in +D and -D patients in the postoperative days, with values significantly higher in -D than +D patients. Fibrinogen and PTT values were significantly higher in -D than +D patients in the 1st postoperative day. IL-1RII plasma levels increased in the postoperative period in both groups. Dexamethasone prophylaxis in pediatric patients undergoing CPB for cardiac surgery is associated with a significant increase of blood PTX3 that could contribute to decreasing inflammatory parameters and improving patient clinical outcome.

Cerebrospinal fluid pentraxin 3 early after subarachnoid hemorrhage is associated with vasospasm.

PURPOSE: To investigate plasma and cerebrospinal fluid (CSF) concentrations of pentraxin 3 (PTX3), a prototypic long pentraxin protein induced by proinflammatory signals, in subarachnoid hemorrhage (SAH), and its relation with SAH-associated vasospasm. METHODS: Serial plasma and CSF samples were collected from 38 consecutive SAH patients admitted to the Neurosurgical Intensive Care. PTX3 concentrations were analyzed in relation to clinical status and clinical vasospasm (defined as neuro-worsening and angiographic confirmation of vessel narrowing). Since neutrophils are an important source of preformed PTX3, myeloperoxidase (MPO) in CSF was measured to assess the correlation with CSF PTX3 and establish whether blood contamination was the determinant of PTX3 increase. RESULTS: PTX3 was elevated in all SAH patients both in plasma and CSF. Acute peak (first 48 h after SAH) CSF PTX3 was significantly higher in patients who later developed vasospasm [median 13.6 (range 2.3-51.9) ng/ml] compared to those who did not [3.2 (0.1-50.5) ng/ml, p = 0.03]. The temporal pattern of CSF PTX3 in patients with vasospasm was triphasic with a peak during the first 48 h after SAH, a subsequent decrease in the following 48-96 h and a secondary significant increase with the occurrence of vasospasm. A loose correlation between CSF PTX3 and MPO was observed (r(2) = 0.13), indicating that following SAH there is a brain production of PTX3. CONCLUSIONS: Acute increased concentrations of PTX3 in CSF but not in plasma are related to the occurrence of vasospasm, indicating that measurement of CSF PTX3 associated with the clinical evaluation can improve early diagnosis of this complication.

Predicting atrial fibrillation recurrence with circulating inflammatory markers in patients in sinus rhythm at high risk for atrial fibrillation: data from the GISSI atrial fibrillation trial.

BACKGROUND: Inflammation may play a significant role in the pathogenesis of atrial fibrillation (AF). OBJECTIVES: To examine the roles of three systemic inflammatory markers in predicting recurrent AF. METHODS: The association between the plasma concentrations of high-sensitivity C reactive protein (hsCRP), interleukin-6 (IL-6) and pentraxin-3 (PTX3) with echocardiographic parameters and with the time to first recurrence of AF was tested in 382 patients with a history of AF but in sinus rhythm at randomisation, enrolled in the GISSI-AF biohumoral study. RESULTS: Baseline PTX3 was related to left atrial, but not to left ventricular chamber volume. During one year of follow-up, 204 patients (53.1%) had a recurrent AF. There were no significant differences in baseline median [Q1-Q3] plasma concentrations of IL-6, hsCRP and PTX3 among patients with (2.11 [1.47-3.74] pg/ml, 3.30 [1.40-6.80] mg/l and 4.66 [3.27-6.97] ng/ml, respectively) or without recurrent AF (2.09 [1.37-2.90] pg/ml, p=0.182; 3.00 [1.10-6.20] mg/l, p=0.333; 5.09 [3.22-7.98] ng/ml, p=0.637). At 6 and 12 months follow-up, AF patients had significantly higher concentrations of IL-6 and PTX3 than those in sinus rhythm, and those with most recent episodes of AF had higher hsCRP. Baseline levels of IL-6, hsCRP or PTX3 were not significantly associated with a higher risk of recurrence of AF. CONCLUSION: In patients with a history of AF, but without significant left ventricular dysfunction or heart failure, inflammatory biomarkers may be raised but are, at best, weak predictors of the risk for first recurrence of AF.

Persisting high levels of plasma pentraxin 3 over the first days after severe sepsis and septic shock onset are associated with mortality.

PURPOSE: Pentraxin 3 (PTX3) is an inflammatory mediator produced by neutrophils, macrophages, myeloid dendritic and endothelial cells. During sepsis a massive inflammatory activation and coagulation/fibrinolysis dysfunction occur. PTX3, as a mediator of inflammation, may represent an early marker of severity and outcome in sepsis. METHODS: This study is based on a prospective trial regarding the impact of glycemic control on coagulation in sepsis. Ninety patients admitted to three general intensive care units were enrolled when severe sepsis or septic shock was diagnosed. At enrollment, we recorded sepsis signs, disease severity, coagulation activation [prothrombin fragments 1 + 2 (F(1+2))] and fibrinolysis inhibition [plasminogen activator inhibitor-1 (PAI-1)]. We measured plasma PTX3 levels at enrollment, everyday until day 7, then at days 9, 11, 13, 18, 23 and 28. Mortality was recorded at day 90. RESULTS: Although not different on day 1, PTX3 remained significantly higher in non-survivors than in survivors over the first 5 days (p = 0.002 by general linear model). On day 1, PTX3 levels were higher in septic shock than in severely septic patients (p = 0.029). Day 1 PTX3 was significantly correlated with platelet count (p < 0.001), SAPS II score (p = 0.006) and SOFA score (p < 0.001). Day 1 PTX3 was correlated with F(1+2) concentration and with PAI-1 activity and concentration (p < 0.05 for all). CONCLUSIONS: Persisting high levels of circulating PTX3 over the first days from sepsis onset may be associated with mortality. PTX3 correlates with severity of sepsis and with sepsis-associated coagulation/fibrinolysis dysfunction.

Pentraxin 3 and C-reactive protein in severe meningococcal disease.

The long pentraxin 3 (PTX3) is an important element of the innate immune system and has potential as a diagnostic tool in inflammatory conditions. We studied PTX3 in patients admitted to an intensive care unit with severe meningococcal disease and compared it with the short pentraxin C-reactive protein (CRP). Twenty-six patients with meningococcal disease were studied, 17 patients presented with meningococcal septic shock (shock group), and 9 patients presented with meningococcal meningitis or bacteremia (no-shock group). Pentraxin 3 and CRP were measured by enzyme-linked immunosorbent assay. High plasma concentrations of PTX3 (median, 579 microg/L) were seen at admission in patients with meningococcal disease. Concentrations were significantly higher in patients with shock compared with patients without shock (medians, 801 and 256 microg/L, respectively; P = 0.006). In contrast, CRP at admission was lower in the shock group as compared with the no-shock group (medians, 58 and 165 mg/L, respectively; P = 0.008). High PTX3 and low CRP concentration at admission discriminated between presence and absence of shock (area under the receiver operating characteristic curve, 0.85; P = 0.007 for PTX3 and area under the receiver operating characteristic curve, 0.84; P = 0.01 for CRP). PTX3 did not correlate with disease severity (pediatric risk of mortality) and days spent in the intensive care unit. PTX3 at admission and PTX3 peak concentration both showed a negative correlation with plasma fibrinogen concentrations. C-reactive protein concentration at admission correlated negatively with disease severity. In conclusion, PTX3 was an early indicator of shock in patients with severe meningococcal disease that followed a pattern of induction distinct from CRP.

Cell-specific regulation of PTX3 by glucocorticoid hormones in hematopoietic and nonhematopoietic cells.

PTX3 (prototypic long pentraxin 3) is a fluid phase pattern recognition receptor, which plays nonredundant roles in the resistance against diverse pathogens, in the assembly of a hyaluronic acid-rich extracellular matrix, and in female fertility. Inflammatory signals induce production of PTX3 in diverse cell types, including myeloid dendritic cells (DC), fibroblasts, and endothelial cells (EC). The present study was designed to explore the effect of glucocorticoid hormones (GC) on PTX3 production in different cellular contexts. In myeloid DC, GC inhibited the PTX3 production. In contrast, in fibroblasts and EC, GC alone induced and, under inflammatory conditions, enhanced and extended PTX3 production. In vivo administration of GC augmented the blood levels of PTX3 in mice and humans. Moreover, patients with Cushing syndrome had increased levels of circulating PTX3, whereas PTX3 levels were decreased in subjects affected by iatrogenic hypocortisolism. In nonhematopoietic cells, GC receptor (GR) functioned as a ligand-dependent transcription factor (dimerization-dependent) to induce PTX3 gene expression. In contrast, in hematopoietic cells, GR repressed PTX3 gene transcription by interfering (dimerization-independent) with the action of other signaling pathways, probably NFkappaB and AP-1. Thus, divergent effects of GC were found to be due to different GR mechanisms. The results presented here indicate that GC have divergent effects on PTX3 production in hematopoietic (DC and macrophages) and nonhematopoietic (fibroblasts and EC) cells. The divergent effects of GC on PTX3 production probably reflect the different functions of this multifunctional molecule in innate immunity and in the construction of the extracellular matrix.

Pentraxin 3 in acute respiratory distress syndrome: an early marker of severity.

OBJECTIVE: Pentraxin 3 is a fluid phase receptor involved in innate immunity. It belongs to the Pentraxins family, as C-reactive protein does. Pentraxin 3 is produced by a variety of tissue cells, whereas only the liver produces C-reactive protein. Pentraxin 3 plays a unique role in the regulation of inflammation. Acute lung injury and acute respiratory distress syndrome are characterized by an important inflammatory reaction. We investigated the role of pentraxin 3 as a marker of severity and outcome predictor of acute lung injury and acute respiratory distress syndrome. DESIGN: We measured circulating pentraxin 3 and C-reactive protein levels within 24 hrs from intubation (day 1), after 24 hrs from the first sample, then every 3 days for the first month and then once a week, until discharge from the intensive care unit. Pentraxin 3 was also measured in bronchoalveolar lavages, performed when clinically indicated. SETTING: One university medical center general intensive care unit. PATIENTS: The study included 21 patients affected by acute lung injury and acute respiratory distress syndrome (1994 Consensus Conference criteria). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Pentraxin 3 plasma levels were high with a peak on the first day (median 71.05 ng/mL, interquartile range 52.37-117.38 ng/mL, normal values <2 ng/mL), declining thereafter. C-reactive protein peaked later and remained at relatively high values. Out of several day 1 parameters, pentraxin 3 was the only significant difference between survivors and nonsurvivors. Pentraxin 3 levels were positively correlated with lung injury score values (p < 0.001) and number of organ failures (p < 0.001). Pentraxin 3 was present in bronchoalveolar lavages fluids (5.03 ng/mL, interquartile range 1.52-8.48 ng/mL) and bronchoalveolar lavages positive to bacterial culture were associated with significantly higher pentraxin 3 values (p < 0.05). CONCLUSIONS: The results presented here show that pentraxin 3 is elevated in acute lung injury and acute respiratory distress syndrome and that its levels correlate with parameters of lung injury and systemic involvement. The clinical and pathophysiological significance of pentraxin 3 in acute lung injury and acute respiratory distress syndrome deserves further scrutiny.

PTX3 as a potential novel tool for the diagnosis and monitoring of pulmonary fungal infections in immuno-compromised pediatric patients.

Pentraxin-3 (PTX3) is a member of the long pentraxin superfamily and has a nonredundant role in mediating resistance to fungal pathogens. Serial monitoring of PTX3 plasmatic levels was performed in 10 pediatric leukemia patients affected by pulmonary fungal infections. When compared with values of a control pediatric cohort, PTX3 showed significantly higher plasmatic values. Moreover, the response to the antifungal therapy correlated with normalization of PTX3 values. PTX3 may represent a useful tool for the diagnosis and monitoring of fungal infections in immuno-compromised children.

The humoral pattern recognition receptor PTX3 is stored in neutrophil granules and localizes in extracellular traps.

The long pentraxin (PTX) 3 is produced by macrophages and myeloid dendritic cells in response to Toll-like receptor agonists and represents a nonredundant component of humoral innate immunity against selected pathogens. We report that, unexpectedly, PTX3 is stored in specific granules and undergoes release in response to microbial recognition and inflammatory signals. Released PTX3 can partially localize in neutrophil extracellular traps formed by extruded DNA. Eosinophils and basophils do not contain preformed PTX3. PTX3-deficient neutrophils have defective microbial recognition and phagocytosis, and PTX3 is nonredundant for neutrophil-mediated resistance against Aspergillus fumigatus. Thus, neutrophils serve as a reservoir, ready for rapid release, of the long PTX3, a key component of humoral innate immunity with opsonic activity.

The long pentraxin PTX3 in vascular pathology.

Pentraxins are a family of evolutionarily conserved multifunctional pattern-recognition proteins characterized by a cyclic multimeric structure. Based on the primary structure of the subunit, the pentraxins are divided into two groups: short pentraxins and long pentraxins. C-reactive protein (CRP) and serum amyloid P-component (SAP) are the two short pentraxins. The prototype protein of the long pentraxin group is pentraxin 3 (PTX3). CRP and SAP are produced primarily in the liver in response to IL-6, while PTX3 is produced by a variety of tissues and cells and in particular by innate immunity cells in response to proinflammatory signals and Toll-like receptor (TLR) engagement. PTX3 interacts with several ligands, including growth factors, extracellular matrix components and selected pathogens, playing a role in complement activation and facilitating pathogen recognition by phagocytes, acting as a predecessor of antibodies. In addition, PTX3 is essential in female fertility by acting as a nodal point for the assembly of the cumulus oophorus hyaluronan-rich extracellular matrix. Thus, the prototypic long pentraxin PTX3 is a multifunctional soluble pattern recognition receptor acting as a non-redundant component of the humoral arm of innate immunity and involved in tuning inflammation, in matrix deposition and female fertility.

Structure and function of the long pentraxin PTX3 glycosidic moiety: fine-tuning of the interaction with C1q and complement activation.

The prototypic long pentraxin PTX3 is a unique fluid-phase pattern recognition receptor that plays a nonredundant role in innate immunity and female fertility. The PTX3 C-terminal domain is required for C1q recognition and complement activation and contains a single N-glycosylation site on Asn 220. In the present study, we characterized the structure of the human PTX3 glycosidic moiety and investigated its relevance in C1q interaction and activation of the complement classical pathway. By specific endo and exoglycosidases digestion and direct mass spectrometric analysis, we found that both recombinant and naturally occurring PTX3 were N-linked to fucosylated and sialylated complex-type sugars. Interestingly, glycans showed heterogeneity mainly in the relative amount of bi, tri, and tetrantennary structures depending on the cell type and inflammatory stimulus. Enzymatic removal of sialic acid or the entire glycosidic moiety equally enhanced PTX3 binding to C1q compared to that in the native protein, thus indicating that glycosylation substantially contributes to modulate PTX3/C1q interaction and that sialic acid is the main determinant of this contribution. BIAcore kinetic measurements returned decreasing K(off) values as sugars were removed, pointing to a stabilization of the PTX3/C1q complex. No major rearrangement of PTX3 quaternary structure was observed after desialylation or deglycosylation as established by size exclusion chromatography. Consistent with C1q binding, PTX3 desialylation enhanced the activation of the classical complement pathway, as assessed by C4 and C3 deposition. In conclusion, our results provided evidence of an involvement of the PTX3 sugar moiety in C1q recognition and complement activation.

The tissue pentraxin PTX3 limits C1q-mediated complement activation and phagocytosis of apoptotic cells by dendritic cells.

Pentraxins (PTX) and complement belong to the humoral arm of the innate immune system and have essential functions in immune defense to microbes and in scavenging cellular debris. The prototypic long PTX, PTX3, and the first component of the classical complement pathway, C1q, are innate opsonins involved in the disposal of dying cells by phagocytes. Whether the interaction between various innate opsonins impacts on their function is not fully understood. We show here that characterized Toll-like receptor (TLR) ligands elicit the production of C1q and PTX3 by immature dendritic cells (DC). Moreover, these molecules bind to dying cells with similar kinetics, although they recognize different domains on the cell membranes. PTX3 binds in the fluid phase to C1q, decreasing C1q deposition and subsequent complement activation on apoptotic cells. C1q increases the phagocytosis of apoptotic cells by DC and the release of interleukin-12 in the presence of TLR4 ligands and apoptotic cells; PTX3 inhibits both events. Moreover, PTX3 inhibited the cross-presentation of the MELAN-A/melanoma antigen-reactive T cell 1 (MART-1) tumor antigen expressed by dying cells, even in the presence of C1q. These results suggest that interaction of C1q and PTX3 influences the clearance of apoptotic cells by DC. The coordinated induction by primary, proinflammatory signals of C1q and PTX3 and their reciprocal regulation during inflammation influences the clearance of apoptotic cells by antigen-presenting cells and possibly plays a role in immune homeostasis.

Regulation of PTX3, a key component of humoral innate immunity in human dendritic cells: stimulation by IL-10 and inhibition by IFN-gamma.

The protopypic long pentraxin 3 (PTX3) is a unique, humoral pattern-recognition receptor, which plays a nonredundant function in innate resistance to pathogens. Dendritic cells (DC) of myelomonocytic origin, but not plasmacytoid DC, are a major source of PTX3 in response to Toll-like receptor (TLR) engagement. The present study was designed to explore the regulation of PTX3 production in DC. PTX3 production was induced by TLR ligands, CD40 ligand, and interleukin (IL)-1beta and was suppressed by dexamethasone, 1alpha, 25-dihydroxivitamin D3, and prostaglandin E2. It was unexpected that lipopolysaccharide (LPS)-stimulated PTX3 production was enhanced by IL-10 and inhibited by IL-4 and interferon-gamma (IFN-gamma). Enhancement of PTX3 production by IL-10 was also evident when Pam3 Cys-Ser-(Lys)4.3HCl, a TLR2-TLR1 agonist, polyionisicpolycytidylic acid, a TLR3 agonist, and IL-1beta were used as stimuli. The effect of IL-10 was blocked by an anti-IL-10 monoclonal antibody (mAb) or an anti-IL-10 receptor alpha mAb, which also reduced the LPS-induced production. Thus, production of PTX3 in DC is subjected to a distinct regulatory network, with inhibition by IFN-gamma and enhancement by IL-10. The amplification by IL-10 of production of a nonredundant component of fluid-phase innate immunity mirrors the IL-10 stimulatory function on B cells in adaptive immunity. As PTX3 is also an extracellular matrix component, IL-10-enhanced PTX3 production may play a role in orchestration of tissue remodeling in chronic inflammation.

Interferon-activated neutrophils store a TNF-related apoptosis-inducing ligand (TRAIL/Apo-2 ligand) intracellular pool that is readily mobilizable following exposure to proinflammatory mediators.

Neutrophils are versatile cells, which play a role, not only in inflammatory processes but also in immune and antitumoral responses. Recently, we have reported that interferon (IFN)-activated neutrophils are able to release biologically active tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL/APO2 ligand), a molecule exerting selective, apoptotic activities toward tumor and virus-infected cells, as well as immunoregulatory functions on activated T lymphocytes. Herein, we show that only a minor fraction of the total TRAIL, newly synthesized by IFN-activated neutrophils within 24 h, is released outside, the rest being retained intracellularly, mainly in secretory vesicles and light membrane fractions. We demonstrate that the intracellular pool of TRAIL present in IFN-pretreated neutrophils is rapidly mobilizable to the cell surface and can be secreted following exposure to proinflammatory mediators such as TNF-alpha, lipopolysaccharide, formyl-methionyl-leucyl-phenylalanine, CXC chemokine ligand 8/interleukin-8, insoluble immunocomplexes, and heat shock protein Gp96. These various proinflammatory agonists functioned as effective secretagogue molecules only, in that they failed to augment TRAIL mRNA expression or TRAIL de novo synthesis in freshly isolated neutrophils or cultured with or without IFN. In addition, supernatants from IFN-treated neutrophils stimulated with proinflammatory mediators induced the apoptosis of target cells more effectively than supernatants from neutrophils activated with IFNs alone. Collectively, our results uncover a novel mechanism, whereby the release of soluble TRAIL by neutrophils can be greatly amplified and further reinforce the notion that neutrophils are important cells in tumor surveillance and immunomodulation.

The pattern recognition receptor PTX3 is recruited at the synapse between dying and dendritic cells, and edits the cross-presentation of self, viral, and tumor antigens.

Pentraxins are soluble pattern recognition receptors with a dual role: protection against extracellular microbes and autoimmunity. The mechanisms by which they accomplish these tasks are not yet fully understood. Here we show that the prototypic long pentraxin PTX3 is specifically recruited at both sides of the phagocytic synapse between dendritic cells (DCs) and dying cells and remains stably bound to the apoptotic membranes (estimated half-time > 36 hours). Apoptotic cells per se influence the production of PTX3 by maturing DCs. When both microbial stimuli and dying cells are present, PTX3 behaves as a flexible adaptor of DC function, regulating the maturation program and the secretion of soluble factors. Moreover a key event associated with autoimmunity (ie, the cross-presentation of epitopes expressed by apoptotic cells to T cells) abates in the presence of PTX3, as evaluated using self, viral, and tumor-associated model antigens (vinculin, NS3, and MelanA/MART1). In contrast, PTX3 did not influence the presentation of exogenous soluble antigens, an event required for immunity against extracellular pathogens. These data suggest that PTX3 acts as a third-party agent between microbial stimuli and dying cells, contributing to limit tissue damage under inflammatory conditions and the activation of autoreactive T cells.

Elevated plasma levels of the long pentraxin, pentraxin 3, in severe dengue virus infections.

C-reactive protein is one of the most widely used indicators of the response of acute-phase proteins. The measurement of C-reactive protein in dengue, however, is clinically not useful, because of marginally elevated levels and absent association with disease severity. The prototypic long pentraxin, pentraxin 3, is an acute phase protein that is structurally related but distinct from C-reactive protein which has proven to correlate with the severity of bacterial infection in critically ill patients. The potential involvement of pentraxin 3 in dengue and its aptitude to predict more severe disease or poor clinical outcome has not been studied previously. We therefore measured pentraxin 3 plasma levels in 44 dengue virus infected patients. Pentraxin 3 levels were strikingly higher when compared to C-reactive protein levels, with highest pentraxin 3 values observed in the first 7 days after the onset of symptoms. Median pentraxin 3 levels at admission and peak levels during follow up were higher in patients suffering from dengue shock syndrome (at admission: 119.3 ng/ml [interquartile range 61.8--188.7], peak values during follow up: 147.9 ng/ml [interquartile range 85.7--204.3]) compared to levels found in patients with dengue fever and dengue hemorrhagic fever (at admission: 59.0 ng/ml [interquartile range 28.6--100.3], P=0.040; peak values during follow up: 80.8 ng/ml [interquartile range 36.1--168.1], P=0.020). Our results indicate that pentraxin 3 seems to be a marker of infection better than C-reactive protein in dengue. The role of pentraxin 3 in the pathogenesis of dengue and its potential as an early prognostic indicator of disease severity needs further assessment.

IFN-gamma-inducible protein 10 and pentraxin 3 plasma levels are tools for monitoring inflammation and disease activity in Mycobacterium tuberculosis infection.

IFN-gamma-inducible protein 10 (IP-10/CXCL10) is a chemokine involved in delayed-type hypersensitivity and attraction of monocytes and activated T lymphocytes at inflammatory foci, whereas pentraxin 3 (PTX3) is part of the innate immune response. In the Republic of Guinea, 220 newly diagnosed, HIV-negative, pulmonary tuberculosis (TB) patients were studied together with 220 healthy household controls and 220 community controls. CXCL10 and PTX3 blood levels were assessed by ELISA at diagnosis, after 2 months and at the end of treatment. In untreated patients, both CXCL10 and PTX3 levels were higher (P < 0.0001) than in controls, although household controls had higher (P < 0.0001) CXCL10 and PTX3 levels than community controls, but lower (P < 0.0001) than those of patients. At the end of treatment, 186 cured patients showed reduction (P < 0.0001) in both CXCL10 and PTX3 levels. In 34 patients with treatment failure, both CXCL10 and PTX3 levels increased further. In five previously healthy households who developed TB during the follow-up and in two patients who relapsed after treatment, a remarkable increase in both CXCL10 and PTX3 plasma levels was observed. Active TB is associated with increased CXCL10 and PTX3 levels in the plasma. Although not specific for TB, measurement of these proteins may help the monitoring of disease activity and efficacy of therapy.

FGF2-induced upregulation of DNA polymerase-delta p12 subunit in endothelial cells.

p12 represents the smallest, so far poorly characterized subunit of the mammalian DNA polymerase delta (pol delta) heterotetramer. Previously, to gain a molecular understanding of endothelial cell activation by fibroblast growth factor-2 (FGF2), we identified an upregulated transcript in FGF2-overexpressing murine aortic endothelial cells (FGF2-T-MAE cells) showing 89% identity with human p12. Here, we cloned the open reading frame of the murine p12 cDNA and confirmed the capacity of overexpressed or exogenously added FGF2 to upregulate p12 mRNA and protein in endothelial and NIH3T3 cells with no effect on the other pol delta subunits. p12 expression was instead unaffected by serum and different mitogens. Also, anti-p12 antibodies decorated FGF2-T-MAE cell nuclei and their chromosome outline during metaphase. Small interfering RNA-mediated knockdown of p12 caused a significant decrease in FGF2-driven proliferation rate of FGF2-T-MAE cells, in keeping with a modulatory role of p12 in pol delta activity. Immunoistochemistry of FGF2-embedded Matrigel plugs and FGF2-overexpressing tumor xenografts demonstrated a nuclear p12 staining of angiogenic CD31(+) endothelium. p12 immunoreactivity was also observed in the CD45(+)/CD11b(+) inflammatory infiltrate. Thus, FGF2 upregulates p12 expression in endothelial cells in vitro and in vivo. p12 expression in infiltrating inflammatory cells may suggest additional, cell proliferation-unrelated functions for this pol delta subunit.

Prognostic significance of the long pentraxin PTX3 in acute myocardial infarction.

BACKGROUND: Inflammation has a pathogenetic role in acute myocardial infarction (MI). Pentraxin-3 (PTX3), a long pentraxin produced in response to inflammatory stimuli and highly expressed in the heart, was shown to peak in plasma approximately 7 hours after MI. The aim of this study was to assess the prognostic value of PTX3 in MI compared with the best-known and clinically relevant biological markers. METHODS AND RESULTS: In 724 patients with MI and ST elevation, PTX3, C-reactive protein (CRP), creatine kinase (CK), troponin T (TnT), and N-terminal pro-brain natriuretic peptide (NT-proBNP) were assayed at entry, a median of 3 hours, and the following morning, a median of 22 hours from symptom onset. With respect to outcome events occurring over 3 months after the index event, median PTX3 values were 7.08 ng/mL in event-free patients, 16.12 ng/mL in patients who died, 9.12 ng/mL in patients with nonfatal heart failure, and 6.88 ng/mL in patients with nonfatal residual ischemia (overall P<0.0001). Multivariate analysis including CRP, CK, TnT, and NT-proBNP showed that only age > or =70 years (OR, 2.11; 95% CI, 1.04 to 4.31), Killip class >1 at entry (OR, 2.20; 95% CI, 1.14 to 4.25), and PTX3 (>10.73 ng/mL) (OR, 3.55; 95% CI, 1.43 to 8.83) independently predicted 3-month mortality. Biomarkers predicting the combined end point of death and heart failure in survivors were the highest tertile of PTX3 and of NT-proBNP and a CK ratio >6. CONCLUSIONS: In a representative contemporary sample of patients with MI with ST elevation, the acute-phase protein PTX3 but not the liver-derived short pentraxin CRP or other cardiac biomarkers (NT-proBNP, TnT, CK) predicted 3-month mortality after adjustment for major risk factors and other acute-phase prognostic markers.