The long pentraxin PTX3 as a prototypic humoral pattern recognition receptor: interplay with cellular innate immunity

The relationship between oxidative stress, inflammation, and atherosclerosis in renal transplant and end-stage renal disease patients

OBJECTIVES

Cardiovascular risk is increased in the early stages of chronic kidney disease (CKD) and is also found to be ongoing in renal transplant (Rtx) patients. As a sign of atherosclerosis, increased carotid intima-media thickness (CIMT) has been widely accepted as a strong predictor of cardiovascular disease (CVD) and mortality in the end-stage renal disease (ESRD) patients. Ischemia-modified albumin (IMA), pentraxin-3 (PTX-3), and neutrophil-to-lymphocyte ratio (NLR) were introduced as oxidative stress and inflammatory biomarkers in ESRD. The role of Rtx in terms of atherogenesis, oxidative stress, and inflammation is still unclear. We aimed to investigate the relationship between IMA, PTX-3, NLR, and CIMT in Rtx patients without overt CVD and to compare these results with those obtained from healthy subjects and ESRD patients receiving hemodialysis (HD) and peritoneal dialysis (PD).

DESIGN AND METHODS

Cross-sectional analysis in which CIMT measurements, NLR, and serum PTX-3 and IMA levels were assessed in 18 Rtx patients (10 females; mean age: 40.0 ± 13.3 years), 16 PD patients (7 females; 40.2 ± 12.9 years), 14 HD patients (8 females; 46.6 ± 10.7 years), and 19 healthy subjects (9 females; 36.9 ± 8.9 years).

RESULTS

IMA, PTX-3, and high-sensitive C-reactive protein (hs-CRP) levels, NLR, and CIMT of Rtx patients were found to be significantly higher compared with healthy subjects ( p = 0.04, p < 0.0001, p < 0.005, p = 0.005, and p = 0.005, respectively). IMA level was positively correlated with hs-CRP and PTX-3 levels, NLR, and CIMT when all participants were included (r = 0.338, p = 0.005; r = 0.485, p < 0.0001; r = 0.304, p = 0.013; and r = 0.499, p < 0.0001, respectively).

CONCLUSION

There has been ongoing inflammation, oxidative stress, and atherosclerosis in Rtx patients.

Increased plasma levels of pentraxin 3 in patients with multiple sclerosis and neuromyelitis optica

Background:

Multiple sclerosis (MS) and neuromyelitis optica (NMO) are immune-mediated inflammatory diseases of the central nervous system. In the acute phase of these diseases, secondary ischemia due to inflammation-induced endothelial dysfunction may be an important pathological change. Pentraxin 3 (PTX3) is a pro-inflammatory protein and a novel biomarker of inflammatory vascular diseases.

Objective:

We aimed to determine whether PTX3 levels are elevated in MS and NMO patients.

Methods:

The concentrations of plasma PTX3 were measured using an enzyme-linked immunosorbent assay in 22 MS patients, 26 NMO patients, 15 acute cerebral infarction (CI) patients, 11 mild headache patients, and 14 volunteer controls.

Results:

During relapse, plasma PTX3 levels were higher in MS patients than in headache patients ( p=0.003) and controls ( p<0.001). Plasma PTX3 levels were also increased in NMO patients compared with CI patients ( p=0.011), headache patients ( p<0.001) and controls ( p<0.001). CI patients showed elevated PTX3 levels compared with controls ( p=0.008). MS and NMO patients showed a trend toward an increased disease disability with higher plasma PTX3 during relapse (MS: p=0.005; NMO: p<0.001). Plasma PTX3 levels were remarkably lower in remission than in the relapse stage (MS: p<0.001; NMO: p<0.001).

Conclusion:

Plasma PTX3 level is associated with inflammatory responses in MS and NMO.

Endogenous modulators of inflammatory cell recruitment

Leukocyte recruitment is a central immune process. Multiple factors have been described to promote leukocyte infiltration into inflamed tissues, but only recently has evidence for endogenous negative modulators of this inflammatory process emerged. The discovery of several locally produced modulators has emerged into a new field of endogenous inhibitors of leukocyte extravasation. Recent findings from several inflammatory disease models show that tissues can self-regulate the recruitment of inflammatory cells, suggesting that local tissues may have a greater 'regulatory say' over the immune response than previously appreciated. Here, we propose that locally produced modulators of leukocyte recruitment may represent local homeostatic mechanisms that tissues and organs may have evolved for protection against the destructive potential of the immune system.

Endothelial pentraxin 3 contributes to murine ischemic acute kidney injury

Toll-like receptor 4 (TLR4), a receptor for damage-associated molecular pattern molecules and also the lipopolysaccharide receptor, is required for early endothelial activation leading to maximal inflammation and injury during murine ischemic acute kidney injury. DNA microarray analysis of ischemic kidneys from TLR4-sufficient and -deficient mice showed that pentraxin 3 (PTX3) was upregulated only on the former while transgenic knockout of PTX3 ameliorated acute kidney injury. PTX3 was expressed predominantly on peritubular endothelia of the outer medulla of the kidney in control mice. Acute kidney injury increased PTX3 protein in the kidney and the plasma where it may be a biomarker of the injury. Stimulation by hydrogen peroxide, or the TLR4 ligands recombinant human high-mobility group protein B1 or lipopolysaccharide, induced PTX3 expression in the Mile Sven 1 endothelial cell line and in primary renal endothelial cells, suggesting that endothelial PTX3 was induced by pathways involving TLR4 and reactive oxygen species. This increase was inhibited by conditional endothelial knockout of myeloid differentiation primary response gene 88, a mediator of a TLR4 intracellular signaling pathway. Compared to wild-type mice, PTX3 knockout mice had decreased endothelial expression of cell adhesion molecules at 4 h of reperfusion, possibly contributing to a decreased early maladaptive inflammation in the kidneys of knockout mice. At 24 h of reperfusion, PTX3 knockout increased expression of endothelial adhesion molecules when regulatory and reparative leukocytes enter the kidney. Thus, endothelial PTX3 plays a pivotal role in the pathogenesis of ischemic acute kidney injury.

PTX3 genetic variation and dizygotic twinning in the Gambia: could pleiotropy with innate immunity explain common dizygotic twinning in Africa?

Dizygotic (DZ) twinning has a genetic component and is common among sub-Saharan Africans; in The Gambia its frequency is up to 3% of live births. Variation in PTX3, encoding Pentraxin 3, a soluble pattern recognition receptor that plays an important role both in innate immunity and in female fertility, has been associated with resistance to Mycobacterium tuberculosis pulmonary disease and to Pseudomonas aeruginosa infection in cystic fibrosis patients. We tested whether PTX3 variants in Gambian women associate with DZ twinning, by genotyping five PTX3 single nucleotide polymorphisms (SNPs) in 130 sister pairs (96 full sibs and 34 half sibs) who had DZ twins. Two, three and five SNP haplotypes differed in frequency between twinning mothers and those without a history of twinning (from P = 0.006 to 3.03e-06 for two SNP and three SNP haplotypes, respectively). Twinning mothers and West African tuberculosis-controls from a previous study shared several frequent haplotypes. Most importantly, our data are consistent with an independently reported association of PTX3 and female fertility in a sample from Ghana. Taken together, these results indicate that selective pressure on PTX3 variants that affect the innate immune response to infectious agents, could also produce the observed high incidence of DZ twinning in Gambians.

Predictors of survival in sepsis: what is the best inflammatory marker to measure?

PURPOSE OF REVIEW

Sepsis is relevant due to its high morbidity and mortality. For both sepsis diagnosis and outcome prediction many biomarkers have been described in the literature. Most of these markers are objects of scientific interest rather than being introduced into daily clinical practice. However, due to their unspecific character and their insufficient predictive value for the individual person, research focus is still on new aspects in sepsis-related biomarkers.

RECENT FINDINGS

Beyond the widely used acute-phase proteins C-reactive protein (CRP) and procalcitonin (PCT), many new molecules have been studied deriving from different organs or cells affected, due to the systemic nature of sepsis. Cytokines, coagulation factors/characteristics, vasoactive hormones, and several others have been recently proved to be relevant in sepsis syndrome and probably useful for outcome prediction. However, single time point measurements may be less predictive than consideration of the time-dependent course of parameters. Clinical decision just based on a biomarker is still not feasible because of the huge inter-individual differences in the inflammatory response.

SUMMARY

Many biomarkers display relevant correlation with the clinical outcome of patients with severe sepsis and septic shock. Consideration of their time courses may be more reliable than absolute levels. Clinical decision should not be based only on biomarkers but organ dysfunctions, for example, should also be taken into account.

Selective up-regulation of the soluble pattern-recognition receptor pentraxin 3 and of vascular endothelial growth factor in giant cell arteritis: relevance for recent optic nerve ischemia

OBJECTIVE

To assess local expression and plasma levels of pentraxin 3 (PTX3) in patients with giant cell arteritis (GCA).

METHODS

Plasma and serum samples were obtained from 75 patients with GCA (20 of whom had experienced optic nerve ischemia in the previous 3 weeks and 24 of whom had experienced symptom onset in the previous 6 months and had no history of optic nerve ischemia) and 63 controls (35 age-matched healthy subjects, 15 patients with rheumatoid arthritis, and 13 patients with chronic stable angina). In 9 patients in whom GCA was recently diagnosed, circulating levels of interleukin-1β (IL-1β), IL-2, IL-4, IL-6, IL-7, IL-8, IL-10, IL-12p70, CCL2/monocyte chemotactic protein 1, CCL3/macrophage inflammatory protein 1α (MIP-1α), CCL4/MIP-1β, CCL11/eotaxin, CXCL9/monokine induced by interferon-γ, CXCL10/interferon-γ-inducible 10-kd protein, tumor necrosis factor α (TNFα), interferon-γ, vascular endothelial growth factor (VEGF), granulocyte-macrophage colony-stimulating factor, and FasL were measured via a multiplexed cytometric assay. PTX3 and VEGF concentrations were assessed by enzyme-linked immunosorbent assay. PTX3 and CD68 expression were determined by immunohistochemistry and immunofluorescence on temporal artery samples.

RESULTS

GCA patients with very recent optic nerve ischemia had significantly higher PTX3 and VEGF levels compared to other GCA patients and controls. GCA patients with a disease duration of <6 months had significantly higher PTX3 levels compared to other GCA patients and controls. Immunohistochemistry revealed selective PTX3 expression in the wall of inflamed arteries.

CONCLUSION

Our findings indicate that local expression of PTX3 is a feature of vascular inflammation in GCA; elevated circulating levels of PTX3 identify patients with very recent optic nerve ischemia or a recent diagnosis. Optic nerve ischemia is also associated with increased circulating VEGF levels.

PTX3 controls activation of matrix metalloproteinase 1 and apoptosis in conjunctivochalasis fibroblasts

PURPOSE

Conjunctivochalasis (CCh) is an age-related inflammatory ocular surface disease manifesting redundant, loose conjunctiva folds. The pathogenic role of Pentraxin 3 (PTX3) in controlling upregulation of matrix metalloproteinase 1 (MMP-1) and MMP-3 in CCh remains undefined.

METHODS

Cytolocation of PTX3 and apoptosis were compared by immunostaining and terminal deoxyribonucleotidyl transferase-mediated FITC-linked dUTP nick-end DNA labeling (TUNEL) assay between normal and CCh specimens containing the conjunctiva and the Tenon. Second to third cultures of normal and CCh fibroblasts were treated with or without Aprotinin, Batimastat, or N-isobutyl-N-(4-methoxyphenylsulfonyl)-glycylhydroxamic acid (NNGH), followed by transfection with or without PTX3 siRNA, and TNF-α or IL-1β. Cell lysates and culture media were collected to assess apoptosis measured by the Cell Death Detection ELISA and expression of PTX3, MMP-1, and MMP-3 transcripts and proteins by quantitative RT-PCR and Western blot, respectively.

RESULTS

PTX3 immunostaining was negative in normal specimens, but strongly positive in the subconjunctival stroma of CCh specimens. More apoptotic cells were found in CCh samples than in normal specimens. Expression of PTX3 transcripts and protein was not constitutive in resting normal fibroblasts but was in resting CCh fibroblasts and was upregulated by IL-1β in both cell lysates and culture media of both fibroblasts. PTX3 siRNA further upregulated MMP-1 and MMP-3 transcripts in resting normal fibroblasts, but synergistically with IL-1β upregulated the expression of MMP-1 and MMP-3 transcripts only in CCh fibroblasts, with activation of MMP-1 more so than MMP-3. PTX3 siRNA knockdown also promoted cell death characterized by apoptosis and necrosis, and such cell death could be rescued by inhibitors against serine proteinase, MMP1, or MMP3.

CONCLUSIONS

Perturbation of PTX3 expression might partake in apoptosis and pathogenesis of CCh by upregulating expression of MMP-1 and MMP-3, and activation of MMP-1 and MMP-3.

Leucocyte recruitment in inflammation and novel endogenous negative regulators thereof

BACKGROUND

The process of extravasation of leucocytes from the vasculature into an infected, inflamed or injured tissue, designated the leucocyte adhesion cascade, is a major process in innate and adaptive immunity. In every immune process, both agonists and inhibitors, that is, positive and negative regulators, exist.

MATERIALS AND METHODS

It was only recently that endogenous inhibitors of the leucocyte adhesion cascade were identified, whereas many selectin, integrin and immunoglobulin superfamily adhesion receptors as well as chemokines and chemokine receptors promoting leucocyte recruitment have been described over the last three decades. Endogenous negative regulators include for instance pentraxin-3 (PTX-3) that blocks selectin-dependent leucocyte rolling, or the endothelium-derived developmental endothelial locus-1 (Del-1) that antagonizes beta2-integrin-mediated firm adhesion of leucocytes to the endothelium.

CONCLUSIONS

As leucocyte infiltration is a major therapeutic target in inflammatory and autoimmune disease, it becomes obvious that such endogenous anti-adhesive and anti-inflammatory agents may represent an attractive novel therapeutic platform for inflammatory and immune disorders. This review focuses on these novel endogenous inhibitors of leucocyte recruitment.

Pentraxin 3(PTX 3): an endogenous modulator of the inflammatory response

Inflammatory or anti-inflammatory? That is the question as far as the acute-phase response and its mediators, the pentraxins, are concerned. Only some ten years ago, the classical or short pentraxin C-reactive protein and the newly discovered long pentraxin PTX3 were considered to exert most of the detrimental effects of acute inflammation, whether microbial or sterile in origin. However, accumulating evidence suggests an at least dichotomous, context-dependent outcome attributable to the pentraxins, if not a straightforward anti-inflammatory nature of the acute-phase response. This paper is focused on the inherent effects of pentraxin 3 in inflammatory responses, mainly in coronary artery disease and in Aspergillus fumigatus infection. Both are examples of inflammatory reactions in which PTX3 is substantially involved; the former sterile, the latter infectious in origin. Apart from different inducing noxae, similarities in the pathogenesis of the two are striking. All the same, the introductory question still persists: is the ultimate impact of PTX3 in these conditions inflammatory or anti-inflammatory, paradoxical as the latter might appear? We try to provide an answer such as it emerges in the light of recent findings.

Serum amyloid A (SAA) induces pentraxin 3 (PTX3) production in rheumatoid synoviocytes

OBJECTIVE

Pentraxin 3 (PTX3) is an acute-phase reactant that is involved in amplification of the inflammatory response and innate immunity. In the present study, we evaluated the relationship between PTX3 and serum amyloid A (SAA), another acute-phase reactant, in rheumatoid synoviocytes.

METHODS

PTX3 mRNA expression was examined by reverse transcription polymerase chain reaction, and PTX3 protein was measured by enzyme-linked immunosorbent assay.

RESULTS

SAA induced PTX3 mRNA and PTX3 protein expression in rheumatoid synoviocytes. SAA-induced PTX3 expression was attenuated when rheumatoid synoviocytes were nucleofected with N-formyl peptide receptor ligand-1 (FPRL-1)-specific siRNA, suggesting the involvement of FPRL-1. Furthermore, SAA-induced PTX3 expression was inhibited by NF-κB or mitogen-activated protein kinase-specific inhibitors. Neither soluble TNF receptor (etanercept) nor recombinant IL-1 receptor antagonist affected PTX3 production by SAA-stimulated synoviocytes, suggesting that SAA directly induces PTX3.

CONCLUSION

Our data suggest that SAA plays a role in the proinflammatory and immune responses in rheumatoid synovium by inducing PTX3. We provide the first evidence that the acute-phase reactant SAA, which is produced systemically by hepatocytes, perpetuates the rheumatoid inflammatory processes by inducing another proinflammatory molecule, PTX3, locally in rheumatoid synovial tissues.

Plasma cell-free DNA levels are elevated in acute Puumala hantavirus infection

Introduction

Puumala hantavirus (PUUV) causes a hemorrhagic fever with renal syndrome called nephropathia epidemica (NE). The aim of the present study was to evaluate plasma cell-free DNA (cf-DNA) levels and urinary cf-DNA excretion in acute NE as well as their associations with the severity of the disease.

Methods

Total plasma cf-DNA was quantified directly in plasma of 61 patients and urine of 20 patients with acute NE. We also carried out a qualitative high-sensitivity lab-on-a-chip DNA assay in 20 patients to elucidate the appearance of cf-DNA in plasma and urine.

Results

The maximum plasma cf-DNA values taken during acute NE were significantly higher than the control values taken after the hospitalization period (median 1.33 µg/ml, range 0.94–3.29 µg/ml vs. median 0.77 µg/ml, range 0.55–0.99 µg/ml, P<0.001). The maximum plasma cf-DNA levels correlated positively with maximum blood leukocyte count (r = 0.388, P = 0.002) and the length of hospital stay (r = 0.376, P = 0.003), and inversely with minimum blood platelet count (r = −0.297, P = 0.020). Qualitative analysis of plasma cf-DNA revealed that in most of the patients cf-DNA displayed a low-molecular weight appearance, corresponding to the size of apoptotic DNA (150–200 bp). The visually graded maximum cf-DNA band intensity correlated positively with the maximum quantity of total plasma cf-DNA (r = 0.513, P = 0.021). Maximum urinary excretion of cf-DNA in turn was not markedly increased during the acute phase of NE and did not correlate with any of the variables reflecting severity of the disease or with the maximum plasma cf-DNA level.

Conclusions

The plasma levels of cf-DNA are elevated during acute PUUV infection and correlate with the apoptotic cf-DNA-band intensity. The plasma cf-DNA concentration correlates with some variables reflecting the severity of the disease. The urinary excretion of cf-DNA does not reflect the degree of inflammation in the kidney.

Pentraxin 3 increase is much less pronounced than C-reactive protein increase after surgical procedures

Pentraxin 3 is an acute phase marker that belongs to the same protein family as C-reactive protein (CRP). The aim of this study was to compare the acute phase reactions of pentraxin 3 and CRP in humans. High sensitivity CRP and pentraxin 3 were analyzed in blood samples from orthopedic surgery (n = 29) and coronary bypass patients (n = 21). The samples were collected prior to surgery and 4 and 30 days after surgery, respectively. Both CRP and pentraxin 3 were significantly increased at day 4. Median pentraxin 3 values increased from 4,021 to 7,459 pg/mL in the orthopedic group and from 4,637 pg/mL to 10,419 pg/mL in the coronary bypass group while CRP increased from 6.3 mg/L to 151.6 mg/L and from 5.7 mg/L to 176.3 mg/L in the same groups. Pentraxin 3 shows a much smaller increment in humans in comparison with CRP.

High pentraxin-3 plasma levels associate with thrombocytopenia in acute Puumala hantavirus-induced nephropathia epidemica

Our aim was to investigate whether plasma levels of the long pentraxin-3 (PTX3) associate with the severity of Puumala hantavirus-induced nephropathia epidemica (NE). Sixty-one prospectively identified consecutively hospitalized NE patients were examined. Plasma PTX3, interleukin (IL)-6, terminal complement complex SC5b-9, complement component C3, C-reactive protein (CRP), creatinine, sodium, kynurenine, and tryptophan levels, as well as the blood cell count, were determined for up to five consecutive days after hospitalization. Receiver operating characteristic (ROC) analysis revealed that the maximum PTX3 level >101.6 ng/ml (high PTX3) showed a sensitivity of 71% and a specificity of 89% for detecting platelet level <50 × 10(9)/l, with an area under the curve (AUC) value of 0.78 (95% confidence interval [CI] 0.63-0.94). High PTX3 level was also associated with several other variables reflecting the severity of the disease: patients with high PTX3 level had higher maximum blood leukocyte (16.1 vs. 9.7 × 10(9)/l, p < 0.001), plasma IL-6 (16.9 vs. 9.0 pg/ml, p = 0.007), and creatinine (282 vs. 124 μmol/l, p = 0.007) levels than patients with low maximum PTX3 level. They also had longer hospital stays (8 vs. 5 days, p = 0.015) compared to patients with low PTX3 level. High plasma PTX3 levels are associated with thrombocytopenia and the overall severity of NE.

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.

Pathogen recognition by the long pentraxin PTX3

Innate immunity represents the first line of defence against pathogens and plays key roles in activation and orientation of the adaptive immune response. The innate immune system comprises both a cellular and a humoral arm. Components of the humoral arm include soluble pattern recognition molecules (PRMs) that recognise pathogen-associated molecular patterns (PAMPs) and initiate the immune response in coordination with the cellular arm, therefore acting as functional ancestors of antibodies. The long pentraxin PTX3 is a prototypic soluble PRM that is produced at sites of infection and inflammation by both somatic and immune cells. Gene targeting of this evolutionarily conserved protein has revealed a nonredundant role in resistance to selected pathogens. Moreover, PTX3 exerts important functions at the cross-road between innate immunity, inflammation, and female fertility. Here, we review the studies on PTX3, with emphasis on pathogen recognition and cross-talk with other components of the innate immune system.

Implication of the oligomeric state of the N-terminal PTX3 domain in cumulus matrix assembly

Pentraxin 3 (PTX3) plays a key role in the formation of the hyaluronan-rich matrix of the cumulus oophorus surrounding ovulated eggs that is required for successful fertilization and female fertility. PTX3 is a multimeric protein consisting of eight identical protomers held together by a combination of non-covalent interactions and disulfide bonds. Recent findings suggest that the oligomeric status of PTX3 is important for stabilizing the cumulus matrix. Because the role of PTX3 in the cumulus resides in the unique N-terminal sequence of the protomer, we investigated further this issue by testing the ability of distinct Cys/Ser mutants of recombinant N-terminal region of PTX3 (N_{_}PTX3) with different oligomeric arrangement to promote in vitro normal expansion in cumuli from Ptx3-null mice. Here we report that the dimer of the N_{_}PTX3 is unable to rescue cumulus matrix organization, and that the tetrameric assembly of the protein is the minimal oligomeric state required for accomplishing this function. We have previously demonstrated that PTX3 binds to HCs of IαI and TSG-6, which are essential for cumulus matrix formation and able to interact with hyaluronan. Interestingly, here we show by solid-phase binding experiments that the dimer of the N_{_}PTX3 retains the ability to bind to both IαI and TSG-6, suggesting that the octameric structure of PTX3 provides multiple binding sites for each of these ligands. These findings support the hypothesis that PTX3 contributes to cumulus matrix organization by cross-linking HA polymers through interactions with multiple HCs of IαI and/or TSG-6. The N-terminal PTX3 tetrameric oligomerization was recently reported to be also required for recognition and inhibition of FGF2. Given that this growth factor has been detected in the mammalian preovulatory follicle, we wondered whether FGF2 negatively influences cumulus expansion and PTX3 may also serve in vivo to antagonize its activity. We found that a molar excess of FGF2, above PTX3 binding capacity, does not affect in vitro cumulus matrix formation thus ruling out this possibility. In conclusion, the data strength the view that PTX3 acts as a nodal molecule in cross-linking HA in the matrix.

Long pentraxin 3 (PTX3) expression and release by neutrophils in vitro and in ulcerative colitis

Pentraxin 3 (PTX3) is the first identified long pentraxin, and it is rapidly produced and released by several cell types in response to proinflammatory signals. The aim of this study was to investigate the behavior of neutrophils to produce PTX3 protein in response to proinflammatory cytokine IL-8 in vitro, as well as identify the expression pattern of PTX3 in human ulcerative colitis lesions. Pentraxin 3 protein was found to be present following release upon IL-8 stimulation in cultured neutrophils together with lactoferrin(+)-specific granules localized in neutrophil extracellular traps (NETs) formed by extruded DNA. Neutrophils in colonic mucosal tissue of patients with ulcerative colitis were the main cellular source of PTX3 protein, the expression of which is correlated well with the histological grades of inflammation. Immunofluorescence analysis against anti-lactoferrin antibody revealed the formation of NETs released from neutrophils within crypt abscess lesions, which were found to be activated through the expression of IL-8 receptor B (CXCR2). Of interest, neutrophils depleted of PTX3 protein were displayed, supporting the release of PTX3 from neutrophils in crypt abscess. We suspected that PTX3 protein may contribute to cell-mediated immune defense in inflamed colon tissue, and in particular in crypt abscess lesions, of patients with ulcerative colitis.

Pentraxin 3 (PTX3) is associated with cardiovascular risk factors: the Health 2000 Survey

Pentraxin 3 (PTX3) is a novel candidate immunoinflammatory marker that has been reported to be associated with cardiometabolic risk factors and to predict adverse outcomes in individuals with cardiovascular disease (CVD). Despite being a member of the same pentraxin protein family as C-reactive protein (CRP), PTX3 probably reflects different aspects of CVD pathogenesis. In this study, we assessed plasma PTX3 correlates and determinants in the Health 2000 Survey population, which comprised n = 403 insulin-resistant subjects, n = 845 hypercholesterolaemic subjects and n = 311 hypertensive subjects, all aged between 46 and 76 years. In insulin-resistant subjects the PTX3 concentration was found to correlate directly with age, pulse pressure and indoleamine 2,3-dioxygenase (IDO) enzyme activity and inversely with total and low-density lipoprotein (LDL) cholesterol. In hypercholesterolaemic subjects, the PTX3 concentration correlated directly with HDL cholesterol, systolic blood pressure and pulse pressure, whereas in hypertensive subjects, the PTX3 concentration correlated directly with systolic blood pressure, pulse pressure and IDO activity. No correlation was observed between the concentrations of PTX3 and CRP, adiposity indicators or indicators of subclinical atherosclerosis in any of the subject groups. PTX3 concentration variations were attributed to variations in LDL cholesterol and IDO activity in insulin-resistant subjects and to pulse pressure in hypercholesterolaemic and hypertensive subjects. These results indicate that, in individuals at high risk of CVD, the PTX3 concentration is associated with cardiovascular risk factors but not with subclinical atherosclerosis.

High plasma level of long pentraxin 3 (PTX3) is associated with fatal disease in bacteremic patients: a prospective cohort study

Introduction

Long pentraxin 3 (PTX3) is an acute-phase protein secreted by various cells, including leukocytes and endothelial cells. Like C-reactive protein (CRP), it belongs to the pentraxin superfamily. Recent studies indicate that high levels of PTX3 may be associated with mortality in sepsis. The prognostic value of plasma PTX3 in bacteremic patients is unknown.

Methods

Plasma PTX3 levels were measured in 132 patients with bacteremia caused by Staphylococcus aureus, Streptococcus pneumoniae, β-hemolytic streptococcae and Escherichia coli, using a commercial solid-phase enzyme-linked immunosorbent assay (ELISA). Values were measured on days 1–4 after positive blood culture, on day 13–18 and on recovery.

Results

The maximum PTX3 values on days 1–4 were markedly higher in nonsurvivors compared to survivors (44.8 vs 6.4 ng/ml, p<0.001) and the AUC^ROC in the prediction of case fatality was 0.82 (95% CI 0.73–0.91). PTX3 at a cut-off level of 15 ng/ml showed 72% sensitivity and 81% specificity for fatal disease. High PTX3 (>15 ng/ml) was associated with hypotension (MAP <70 mmHg)(OR 7.9;95% CI 3.3–19.0) and high SOFA score (≥4)(OR 13.2; 95% CI 4.9–35.4). The CRP level (maximum value on days 1 to 4) did not predict case fatality at any cut-off level in the ROC curve (p = 0.132). High PTX3 (>15 ng/ml) remained an independent risk factor for case fatality in a logistic regression model adjusted for potential confounders.

Conclusions

PTX3 proved to be a specific independent prognostic biomarker in bacteremia. PTX3 during the first days after diagnosis showed better prognostic value as compared to CRP, a widely used biomarker in clinical settings. PTX3 measurement offers a novel opportunity for the prognostic stratification of bacteremia patients.

Soluble TWEAK and PTX3 in nondialysis CKD patients: impact on endothelial dysfunction and cardiovascular outcomes

BACKGROUND AND OBJECTIVES

Chronic kidney disease (CKD) conveys high mortality rates. Soluble TNF-like weak inducer of apoptosis (sTWEAK) and long pentraxin 3 (PTX3) are predictors of mortality in dialysis patients and determinants of endothelial dysfunction. Now, we hypothesize that both sTWEAK and PTX3 act as biomarkers of cardiovascular outcomes in nondialysis CKD patients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Cross-sectional analysis in which flow-mediated dilation (FMD) and intima-media thickness (IMT) were assessed in 257 nondialysis stage 1 to 5 CKD patients (mean age, 52 ± 12 years; 130 men), together with biochemical measurements and sTWEAK and PTX3 assessments. Patients were followed for cardiovascular outcomes.

RESULTS

PTX3 and IMT increased, whereas FMD and sTWEAK decreased across CKD stages (P<0.001 for all). Both PTX3 and sTWEAK appeared as strong determinants of FMD in multivariate analysis. The univariate associations of sTWEAK and PTX3 with IMT were dependent on estimated GFR. After a median of 39 months (range, 2 to 43 months), 22 fatal and 57 nonfatal cardiovascular events occurred. In a Cox model excluding PTX3, decreasing sTWEAK concentration was associated with increased risk of cardiovascular events independently of basic confounders (age, gender, estimated GFR, C reactive protein, diabetes, and cardiovascular comorbidity) and FMD. In a model excluding sTWEAK, circulating levels of PTX3 were directly associated with cardiovascular outcomes independently of basic confounders, but this association was lost after adjustment for FMD.

CONCLUSIONS

Both PTX3 and sTWEAK levels associated with the endothelial dysfunction observed with progressive kidney failure. Additionally, both biomarkers impacted the predictability of cardiovascular outcomes.

Syndecan-1 knock-down in decidualized human endometrial stromal cells leads to significant changes in cytokine and angiogenic factor expression patterns

BACKGROUND

Successful embryonic implantation depends on a synchronized embryo-maternal dialogue. Chemokines, such as chemokine ligand 1 (CXCL1), play essential roles in the maternal reproductive tract leading to morphological changes during decidualization, mediating maternal acceptance towards the semi-allograft embryo and induction of angiogenesis. Chemokine binding to their classical G-protein coupled receptors is essentially supported by the syndecan (Sdc) family of heparan sulfate proteoglycans. The aim of this study was to identify the involvement of Sdc-1 at the embryo-maternal interface regarding changes of the chemokine and angiogenic profile of the decidua during the process of decidualization and implantation in human endometrium.

METHODS

A stable Sdc-1 knock-down was generated in the immortalized human endometrial stromal cell line St-T1 and was named KdS1. The ability of KdS1 to decidualize was proven by Insulin-like growth factor binding 1 (IGFBP1) and prolactin (PRL) confirmation on mRNA level before further experiments were carried out. Dot blot protein analyses of decidualized knock-down cells vs non-transfected controls were performed. In order to imitate embryonic implantation, decidualized KdS1 were then incubated with IL-1beta, an embryo secretion product, vs controls. Statistical analyses were performed applying the Student's t-test with p < 0.05, p < 0.02 and p < 0.01 and one way post-hoc ANOVA test with p < 0.05 as cut-offs for statistical significance.

RESULTS

The induction of the Sdc-1 knock-down revealed significant changes in cytokine and angiogenic factor expression profiles of dKdS1 vs decidualized controls. Incubation with embryonic IL-1beta altered the expression patterns of KdS1 chemokines and angiogenic factors towards inflammatory-associated molecules and factors involved in matrix regulation.

CONCLUSIONS

Sdc-1 knock-down in human endometrial stroma cells led to fulminant changes regarding cytokine and angiogenic factor expression profiles upon decidualization and imitation of embryonic contact. Sdc-1 appears to play an important role as a co-receptor and storage factor for many cytokines and angiogenic factors during decidualization and implantation period, supporting proper implantation and angiogenesis by regulation of chemokine and angiogenic factor secretion in favour of the implanting embryo.

Cigarette smoke induces PTX3 expression in pulmonary veins of mice in an IL-1 dependent manner

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is associated with abnormal inflammatory responses and structural alterations of the airways, lung parenchyma and pulmonary vasculature. Since Pentraxin-3 (PTX3) is a tuner of inflammatory responses and is produced by endothelial and inflammatory cells upon stimuli such as interleukin-1β (IL-1β), we hypothesized that PTX3 is involved in COPD pathogenesis.

METHODS AND RESULTS

We evaluated whether cigarette smoke (CS) triggers pulmonary and systemic PTX3 expression in vivo in a murine model of COPD. Using immunohistochemical (IHC) staining, we observed PTX3 expression in endothelial cells of lung venules and veins but not in lung arteries, airways and parenchyma. Moreover, ELISA on lung homogenates and semi-quantitative scoring of IHC-stained sections revealed a significant upregulation of PTX3 upon subacute and chronic CS exposure. Interestingly, PTX3 expression was not enhanced upon subacute CS exposure in IL-1RI KO mice, suggesting that the IL-1 pathway is implicated in CS-induced expression of vascular PTX3. Serum PTX3 levels increased rapidly but transiently after acute CS exposure.To elucidate the functional role of PTX3 in CS-induced responses, we examined pulmonary inflammation, protease/antiprotease balance, emphysema and body weight changes in WT and Ptx3 KO mice. CS-induced pulmonary inflammation, peribronchial lymphoid aggregates, increase in MMP-12/TIMP-1 mRNA ratio, emphysema and failure to gain weight were not significantly different in Ptx3 KO mice compared to WT mice. In addition, Ptx3 deficiency did not affect the CS-induced alterations in the pulmonary (mRNA and protein) expression of VEGF-A and FGF-2, which are crucial regulators of angiogenesis.

CONCLUSIONS

CS increases pulmonary PTX3 expression in an IL-1 dependent manner. However, our results suggest that either PTX3 is not critical in CS-induced pulmonary inflammation, emphysema and body weight changes, or that its role can be fulfilled by other mediators with overlapping activities.

Pentraxin 3 in maternal circulation: an association with preterm labor and preterm PROM, but not with intra-amniotic infection/inflammation

OBJECTIVE

Pentraxin 3 (PTX3) is an acute-phase protein that has an important role in the regulation of the innate immune response. The aim of this study was to determine if maternal plasma PTX3 concentration changes in the presence of intra-amniotic infection and/or inflammation (IAI) in women with preterm labor (PTL) and intact membranes, as well as those with preterm prelabor rupture of membranes (preterm PROM).

STUDY DESIGN

This cross-sectional study included women in the following groups: (1) nonpregnant (n=40); (2) uncomplicated pregnancies in the first (n=22), second (n=22) or third trimester (n=71, including 50 women at term not in labor); (3) uncomplicated pregnancies at term with spontaneous labor (n=49); (4) PTL and intact membranes who delivered at term (n=49); (5) PTL without IAI who delivered preterm (n=26); (6) PTL with IAI (n=65); (7) preterm PROM without IAI (n=25); and (8) preterm PROM with IAI (n=77). Maternal plasma PTX3 concentrations were determined by ELISA.

RESULTS

(1) Maternal plasma PTX3 concentrations increased with advancing gestational age (r=0.62, p<0.001); (2) women at term with spontaneous labor had a higher median plasma PTX3 concentration than those at term not in labor (8.29 ng/ml vs. 5.98  ng/ml, p=0.013); (3) patients with an episode of PTL, regardless of the presence or absence of IAI and whether these patients delivered preterm or at term had a higher median plasma PTX3 concentration than normal pregnant women (p<0.001 for all comparisons); (4) similarly, patients with preterm PROM, with or without IAI had a higher median plasma PTX3 concentration than normal pregnant women (p<0.001 for both comparisons); and (5) among patients with PTL and those with preterm PROM, IAI was not associated with significant changes in the median maternal plasma PTX3 concentrations.

CONCLUSIONS

The maternal plasma PTX3 concentration increases with advancing gestational age and is significantly elevated during labor at term and in the presence of spontaneous preterm labor or preterm PROM. These findings could not be explained by the presence of IAI, suggesting that the increased PTX3 concentration is part of the physiologic or pathologic activation of the pro-inflammatory response in the maternal circulation during the process of labor at term or preterm.

Pentraxins in innate immunity: lessons from PTX3

The innate immune system constitutes the first line of defence against microorganisms and plays a primordial role in the activation and regulation of adaptive immunity. The innate immune system is composed of a cellular arm and a humoral arm. Components of the humoral arm include members of the complement cascade and soluble pattern recognition molecules (PRMs). These fluid-phase PRMs represent the functional ancestors of antibodies and play a crucial role in the discrimination between self, non-self and modified-self. Moreover, evidence has been presented that these soluble PRMs participate in the regulation of inflammatory responses and interact with the cellular arm of the innate immune system. Pentraxins consist of a set of multimeric soluble proteins and represent the prototypic components of humoral innate immunity. Based on the primary structure of the protomer, pentraxins are divided into two groups: short pentraxins and long pentraxins. The short pentraxins C-reactive protein and serum amyloid P-component are produced by the liver and represent the main acute phase proteins in human and mouse, respectively. The long pentraxin PTX3 is produced by innate immunity cells (e.g. PMN, macrophages, dendritic cells), interacts with several ligands and plays an essential role in innate immunity, tuning inflammation and matrix deposition. PTX3 provides a paradigm for the mode of action of humoral innate immunity.

An integrated view of humoral innate immunity: pentraxins as a paradigm

The innate immune system consists of a cellular and a humoral arm. Pentraxins (e.g., the short pentraxin C reactive protein and the long pentraxin PTX3) are key components of the humoral arm of innate immunity which also includes complement components, collectins, and ficolins. In response to microorganisms and tissue damage, neutrophils, macrophages, and dendritic cells are major sources of fluid-phase pattern-recognition molecules (PRMs) belonging to different molecular classes. Humoral PRMs in turn interact with and regulate cellular effectors. Effector mechanisms of the humoral innate immune system include activation and regulation of the complement cascade; agglutination and neutralization; facilitation of recognition via cellular receptors (opsonization); and regulation of inflammation. Thus, the humoral arm of innate immunity is an integrated system consisting of different molecules and sharing functional outputs with antibodies.

Tasting the fungal cell wall

The search for common host mechanisms that recognize human fungal pathogens as non-self has led to an increased interest in cell wall polysaccharides since they are absent from mammals and at least for some of them, common to all fungal species. Even though the receptors recognizing mannans and beta-1,3-glucans have been extensively studied to date, the epitope of the polysaccharide ligand is often not well defined. In addition, receptors recognizing other cell wall major components such as chitin, alpha-1,3-glucan or galactose polymers remain to be identified. Moreover, the fungal adhesins playing a role in adhesion to host have been only explored in yeasts. Eventhough progresses have been made in the last 10 years, a comprehensive understanding of the interactions between the host membrane receptors and the fungal cell wall components is still lacking.

The angiogenic inhibitor long pentraxin PTX3 forms an asymmetric octamer with two binding sites for FGF2

The inflammation-associated long pentraxin PTX3 plays key roles in innate immunity, female fertility, and vascular biology (e.g. it inhibits FGF2 (fibroblast growth factor 2)-mediated angiogenesis). PTX3 is composed of multiple protomers, each composed of distinct N- and C-terminal domains; however, it is not known how these are organized or contribute to its functional properties. Here, biophysical analyses reveal that PTX3 is composed of eight identical protomers, associated through disulfide bonds, forming an elongated and asymmetric, molecule with two differently sized domains interconnected by a stalk. The N-terminal region of the protomer provides the main structural determinant underlying this quaternary organization, supporting formation of a disulfide-linked tetramer and a dimer of dimers (a non-covalent tetramer), giving rise to the asymmetry of the molecule. Furthermore, the PTX3 octamer is shown to contain two FGF2 binding sites, where it is the tetramers that act as the functional units in ligand recognition. Thus, these studies provide a unifying model of the PTX3 oligomer, explaining both its quaternary organization and how this is required for its antiangiogenic function.

Rolling back neutrophil adhesion

Neutrophils and other cells secrete pentraxin 3, which promotes innate immunity by binding to pathogens and activating complement. New work shows that pentraxin 3 also limits neutrophil recruitment by inhibiting rolling on P-selectin in inflamed venules.

Pentraxin 3 in amniotic fluid: a novel association with intra-amniotic infection and inflammation

OBJECTIVE

Pentraxin 3 (PTX3) is a soluble pattern recognition receptor (PRR) that has an important role in immunoregulation and vascular integrity. The aim of this study was to determine if PTX3 is present in amniotic fluid (AF) and whether its concentration changes with gestational age (GA), in the presence of preterm or term labor, and in cases of intra-amniotic infection/inflammation (IAI) associated with spontaneous preterm labor (PTL) or preterm prelabor rupture of membranes (PROM).

STUDY DESIGN

This cross-sectional study included the following groups: 1) mid-trimester (n=45); 2) uncomplicated pregnancies at term with (n=48) and without (n=40) spontaneous labor; 3) women with PTL and intact membranes who: a) delivered at term (n=44); b) delivered preterm without IAI (n=40); or c) delivered preterm with IAI (n=62); 4) women with preterm PROM with (n=63) and without (n=36) IAI. PTX3 concentration in AF was determined by ELISA. Non-parametric statistics were used for analyses.

RESULTS

1) Among women with PTL and intact membranes, the median AF PTX3 concentration was significantly higher in women with IAI than in those without IAI (7.95 ng/mL vs. 0.38 ng/mL; P<0.001) and than in those who delivered at term (0.55 ng/mL; P<0.001); 2) women with preterm PROM and IAI had a higher median AF PTX3 concentration than those without IAI (9.12 ng/mL vs. 0.76 ng/mL; P<0.001); 3) the median AF PTX3 concentration did not change with GA (mid-trimester: 0.79 ng/mL vs. term not in labor: 0.58 ng/mL; P=0.09); and 4) labor at term was not associated with a significant change of AF PTX 3 concentration (in labor: 0.54 ng/mL vs. not in labor: 0.58 ng/mL, P=0.9).

CONCLUSIONS

PTX3 is a physiologic constituent of the AF, and its median concentration is elevated in the presence of IAI, suggesting that PTX3 may play a role in the innate immune response against IAI.

Comparative gene expression profiling between human cultured myotubes and skeletal muscle tissue

Background

A high-sensitivity DNA microarray platform requiring nanograms of RNA input facilitates the application of transcriptome analysis to individual skeletal muscle (SM) tissue samples. Culturing myotubes from SM-biopsies enables investigating transcriptional defects and assaying therapeutic strategies. This study compares the transcriptome of aneurally cultured human SM cells versus that of tissue biopsies.

Results

We used the Illumina expression BeadChips to determine the transcriptomic differences between tissue and cultured SM samples from five individuals. Changes in the expression of several genes were confirmed by QuantiGene Plex assay or reverse transcription real-time PCR. In cultured myotubes compared to the tissue, 1216 genes were regulated: 583 down and 633 up. Gene ontology analysis showed that downregulated genes were mainly associated with cytoplasm, particularly mitochondria, and involved in metabolism and the muscle-system/contraction process. Upregulated genes were predominantly related to cytoplasm, endoplasmic reticulum, and extracellular matrix. The most significantly regulated pathway was mitochondrial dysfunction. Apoptosis genes were also modulated. Among the most downregulated genes detected in this study were genes encoding metabolic proteins AMPD1, PYGM, CPT1B and UCP3, muscle-system proteins TMOD4, MYBPC1, MYOZ1 and XIRP2, the proteolytic CAPN3 and the myogenic regulator MYF6. Coordinated reduced expression of five members of the GIMAP gene family, which form a cluster on chromosome 7, was shown, and the GIMAP4-reduction was validated. Within the most upregulated group were genes encoding senescence/apoptosis-related proteins CDKN1A and KIAA1199 and potential regulatory factors HIF1A, TOP2A and CCDC80.

Conclusions

Cultured muscle cells display reductive metabolic and muscle-system transcriptome adaptations as observed in muscle atrophy and they activate tissue-remodeling and senescence/apoptosis processes.

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.

Combination of host susceptibility and Mycobacterium tuberculosis virulence define gene expression profile in the host

Progression and outcome of tuberculosis is governed by extensive crosstalk between pathogen and host. Analyses of global changes in gene expression during immune response to infection with Mycobacterium tuberculosis (M.tb) can help identify molecular markers of disease state and progression. Global distribution of M.tb strains with different degrees of virulence and drug resistance, especially for the immunocompromised host, make closer analyses of host responses more pressing than ever. Here, we describe global transcriptional responses of inducible nitric oxide synthase-deficient (iNOS(-/-)) and WT mice infected with two related M.tb strains of markedly different virulence, namely the M.tb laboratory strains H37Rv and H37Ra. Both hosts exhibited highly similar resistance to infection with H37Ra. In contrast, iNOS(-/-) mice rapidly succumbed to H37Rv, whereas WT mice developed chronic course of disease. By differential analyses, virulence-specific changes in global host gene expression were analyzed to identify molecular markers characteristic for chronic versus acute infection. We identified several markers unique for different stages of disease progression and not previously associated with virulence-specific host responses in tuberculosis.

Genetic variation in pentraxin (PTX) 3 gene associates with PTX3 production and fertility in women

Pentraxin 3 (PTX3) plays an important role in innate immune responses and in female fertility, as discovered with studies in mice. However, the role of PTX3 in human fertility is unknown. Here, we report on a population-based study from a rural area of Upper East Ghana (n = 4346). We studied the association between the number of children given birth by women during their lifetime and ex vivo, lipopolysaccharide (LPS)-induced PTX3 production (n = 362). In addition, we studied the association of genetic variation in the PTX3 gene with PTX3 production (n = 617) and with female fertility (n = 1999). We found that ex vivo LPS-induced PTX3 production was associated with fertility (P = 0.040). Furthermore, we identified genetic variants in the PTX3 gene that influence PTX3 production, and also fertility. The strongest associations were observed for the rs6788044 single-nucleotide polymorphism (SNP). We found that carriers of this SNP had higher PTX3 production capacity (P = 0.003) and higher fertility (P = 0.043). The results reported here provide the first evidence, based on protein production and analysis of polymorphisms, that the long pentraxin PTX3 plays a role in female fertility in humans.

Pathogenesis of Aspergillus fumigatus in Invasive Aspergillosis

Aspergillus species are globally ubiquitous saprophytes found in a variety of ecological niches. Almost 200 species of aspergilli have been identified, less than 20 of which are known to cause human disease. Among them, Aspergillus fumigatus is the most prevalent and is largely responsible for the increased incidence of invasive aspergillosis (IA) in the immunocompromised patient population. IA is a devastating illness, with mortality rates in some patient groups reaching as high as 90%. Studies identifying and assessing the roles of specific factors of A. fumigatus that contribute to the pathogenesis of IA have traditionally focused on single-gene deletion and mutant characterization. In combination with recent large-scale approaches analyzing global fungal responses to distinct environmental or host conditions, these studies have identified many factors that contribute to the overall pathogenic potential of A. fumigatus. Here, we provide an overview of the significant findings regarding A. fumigatus pathogenesis as it pertains to invasive disease.

Macrophage diversity and polarization in atherosclerosis: a question of balance

Diversity and plasticity are hallmarks of mononuclear phagocytes, which are reflected in plaque formation and evolution. Different monocyte subsets, which differentially contribute to plaque infiltration and to atherosclerosis complications, have been identified. Similarly, depending on different environmental signals plaque-associated macrophages can express polarized pro- and antiatherogenic programs by influencing lipid metabolism, inflammatory responses, and plaque stability. Thus, a "macrophage balance" plays a major role in the pathogenesis of atherosclerotic plaques and affects evolution and complications of atherosclerosis.