Oncostatin M Induces a Pro-inflammatory Phenotype in Intestinal Subepithelial Myofibroblasts.

BACKGROUND: Oncostatin-M (OSM) is associated with antitumor necrosis factor (anti-TNF)-α resistance in inflammatory bowel disease (IBD) and fibrosis in inflammatory diseases. We studied the expression of OSM and its receptors (OSMR, gp130) on intestinal subepithelial myofibroblasts (SEMFs) and the effect of OSM stimulation on SEMFs. METHODS: The mRNA and protein expression of OSM, OSMR, gp130, and several fibrotic and chemotactic factors were studied in mucosal biopsies and isolated human intestinal SEMFs of patients with IBD and healthy controls (HCs) and in a model of human intestinal organoids (HIOs). Subepithelial myofibroblasts and HIOs were stimulated with OSM and interleukin (IL)-1α/TNF-α. RNAseq data of mucosal biopsies were also analyzed. RESULTS: Oncostatin-M receptors and gp130 were overexpressed in mucosal biopsies of patients with IBD (P < .05), especially in inflamed segments (P < .05). The expression of OSM, OSMR, and gp130 in SEMFs from HCs was increased after stimulation with IL-1α/TNF-α (P < .001; P < .01; P < .01). The expression of CCL2, CXCL9, CXCL10, and CXCL11 was increased in SEMFs from patients with IBD and HCs after stimulation with OSM in a dose-dependent manner (P < .001; P < .05; P < .001; P < .001) and was further increased after prestimulation with IL-1α/TNF-α (P < .01 vs OSM-alone). Similar results were yielded after stimulation of HIOs (P < .01). Oncostatin-M did not induce the expression of collagen I, III, and fibronectin. Oncostatin-M receptor expression was positively correlated with CCL2, CXCL9, CXCL10, and CXCL11 expression in mucosal biopsies (P < .001; P < .001; P = .045; P = .033). CONCLUSIONS: Human SEMFs overexpress OSMR in an inflammatory microenvironment. Oncostatin-M may promote inflammation in IBD via its stimulatory effects on SEMFs, which primarily involve chemoattraction of immune cells to the intestinal mucosa.

Oncostatin-M/OSMR show elevated expression on intestinal fibroblasts that is regulated by IBD-relevant pro-inflammatory stimuli. In turn, OSM induces a pro-inflammatory phenotype on primary intestinal fibroblasts, with prominent overexpression of chemotactic factors, without demonstrating a substantial profibrotic effect.

Mitochondrial Fraction of Circulating Cell-Free DNA as an Indicator of Human Pathology.

Circulating cell-free DNA (ccfDNA) of mitochondrial origin (ccf-mtDNA) consists of a minor fraction of total ccfDNA in blood or in other biological fluids. Aberrant levels of ccf-mtDNA have been observed in many pathologies. Here, we introduce a simple and effective standardized Taqman probe-based dual-qPCR assay for the simultaneous detection and relative quantification of nuclear and mitochondrial fragments of ccfDNA. Three pathologies of major burden, one malignancy (Breast Cancer, BrCa), one inflammatory (Osteoarthritis, OA) and one metabolic (Type 2 Diabetes, T2D), were studied. Higher levels of ccf-mtDNA were detected both in BrCa and T2D in relation to health, but not in OA. In BrCa, hormonal receptor status was associated with ccf-mtDNA levels. Machine learning analysis of ccf-mtDNA datasets was used to build biosignatures of clinical relevance. (A) a three-feature biosignature discriminating between health and BrCa (AUC: 0.887) and a five-feature biosignature for predicting the overall survival of BrCa patients (Concordance Index: 0.756). (B) a five-feature biosignature stratifying among T2D, prediabetes and health (AUC: 0.772); a five-feature biosignature discriminating between T2D and health (AUC: 0.797); and a four-feature biosignature identifying prediabetes from health (AUC: 0.795). (C) a biosignature including total plasma ccfDNA with very high performance in discriminating OA from health (AUC: 0.934). Aberrant ccf-mtDNA levels could have diagnostic/prognostic potential in BrCa and Diabetes, while the developed multiparameter biosignatures can add value to their clinical management.

Niclosamide Attenuates Inflammation-Associated Profibrotic Responses in Human Subepithelial Lung Myofibroblasts.

Niclosamide is a commonly used helminthicidic drug for the treatment of human parasitosis by helminths. Recently, efforts have been focusing on repurposing this drug for the treatment of other diseases, such as idiopathic pulmonary fibrosis. Subepithelial lung myofibroblasts (SELMs) isolated from tissue biopsies of patients undergoing surgery for lung cancer were stimulated with TNF-α (50 ng/mL), IL-1α (5 ng/mL), added alone or in combination, and TGF-ß1 (5 ng/mL). After treatment with niclosamide at 30 nM and 100 nM concentrations, expression of collagen type I, collagen type III, and fibronectin was studied by total RNA isolation and qRT-PCR and protein collagen secretion with the use of Sircol collagen assay. The migration of SELMs was assessed by a wound-healing assay. Niclosamide had no effect on baseline SELM fibrotic factor expression. When stimulated with TGF-ß1, IL-1α, and/or TNF-α, SELM expression of collagen type I, type III, and fibronectin were upregulated, as was the secretion of total collagen in the culture medium. Treatment with niclosamide attenuated the effects of cytokine stimulation leading to a notable decrease in the mRNA expression of collagen type I, type III, and fibronectin in a concentration-dependent manner. SELM collagen secretion was also reduced by niclosamide at 100 nM concentration when examined at the protein level. Migration of both TGF-ß1 stimulated and unstimulated SELMs was also inhibited by niclosamide. In this study, we highlight the anti-fibrotic properties of niclosamide on SELMs under stimulation with pro-fibrotic and pro-inflammatory cytokines, thus proposing this compound as a possible new therapeutic agent against lung fibrosis.

A Simplified and Effective Approach for the Isolation of Small Pluripotent Stem Cells Derived from Human Peripheral Blood.

Pluripotent stem cells are key players in regenerative medicine. Embryonic pluripotent stem cells, despite their significant advantages, are associated with limitations such as their inadequate availability and the ethical dilemmas in their isolation and clinical use. The discovery of very small embryonic-like (VSEL) stem cells addressed the aforementioned limitations, but their isolation technique remains a challenge due to their small cell size and their efficiency in isolation. Here, we report a simplified and effective approach for the isolation of small pluripotent stem cells derived from human peripheral blood. Our approach results in a high yield of small blood stem cell (SBSC) population, which expresses pluripotent embryonic markers (e.g., Nanog, SSEA-3) and the Yamanaka factors. Further, a fraction of SBSCs also co-express hematopoietic markers (e.g., CD45 and CD90) and/or mesenchymal markers (e.g., CD29, CD105 and PTH1R), suggesting a mixed stem cell population. Finally, quantitative proteomic profiling reveals that SBSCs contain various stem cell markers (CD9, ITGA6, MAPK1, MTHFD1, STAT3, HSPB1, HSPA4), and Transcription reg complex factors (e.g., STAT5B, PDLIM1, ANXA2, ATF6, CAMK1). In conclusion, we present a novel, simplified and effective isolating process that yields an abundant population of small-sized cells with characteristics of pluripotency from human peripheral blood.

Anti-Inflammatory and Anti-Fibrotic Effect of Immortalized Mesenchymal-Stem-Cell-Derived Conditioned Medium on Human Lung Myofibroblasts and Epithelial Cells.

Idiopathic pulmonary fibrosis (IPF) is caused by progressive lung tissue impairment due to extended chronic fibrosis, and it has no known effective treatment. The use of conditioned media (CM) from an immortalized human adipose mesenchymal stem cell line could be a promising therapeutic strategy, as it can reduce both fibrotic and inflammatory responses. We aimed to investigate the anti-inflammatory and anti-fibrotic effect of CM on human pulmonary subepithelial myofibroblasts (hPSM) and on A549 pulmonary epithelial cells, treated with pro-inflammatory or pro-fibrotic mediators. CM inhibited the proinflammatory cytokine-induced mRNA and protein production of various chemokines in both hPSMs and A549 cells. It also downregulated the mRNA expression of IL-1α, but upregulated IL-1ß and IL-6 mRNA production in both cell types. CM downregulated the pro-fibrotic-induced mRNA expression of collagen Type III and the migration rate of hPSMs, but upregulated fibronectin mRNA production and the total protein collagen secretion. CM's direct effect on the chemotaxis and cell recruitment of immune-associated cells, and its indirect effect on fibrosis through the significant decrease in the migration capacity of hPSMs, makes it a plausible candidate for further development towards a therapeutic treatment for IPF.

Imbalance of growth factors mRNA expression associated with oxidative stress in the early pregnancy loss.

OBJECTIVE: The aim of this study was to examine the role of growth factors associated with angiogenesis and oxidative stress in the pathogenesis of spontaneous miscarriage. METHODS: We performed a comparative mRNA expression analysis of VEGF, PlGF, Flt-1, Angiogenin and Endoglin using Real-Time PCR, in the placenta and decidua collected from 12 patients presenting with spontaneous abortion and from 14 women undergoing induced abortion, during the first and second trimester of pregnancy. RESULTS: The mRNA expression of Flt-1 was significantly upregulated in the placenta of spontaneous abortions (5.17-fold, IQR: 2.72-9.11, p < 0.01). The placental expression of the soluble isoforms of Flt-1, sFlt-1 e15a and sFlt-1 i13, was also significantly upregulated in spontaneous abortions (sFlt-1 e15a: 2.35-fold, IQR: 0.98-2.83, p < 0.01; sFlt-1 i13: 3.47-fold, IQR: 2.37-5.08, p < 0,05). Placental tmFlt-1, PlGF and Endoglin showed a tendency of higher expression levels in spontaneous abortions, although they did not reach statistical significance (tmFlt-1: 7.42-fold, IQR: 3.58-14.32; PlGF: 2.36-fold, IQR: 0.90-4.12; Endoglin: 1.97-fold, IQR: 1.18-2.43). VEGF and Angiogenin mRNA expression in induced, as well as in spontaneous abortions, did not convey any statistically significant difference. In the decidua, the expression levels of Flt-1 and its splice variants sFlt-1 e15a, sFlt-1 i13 and tmFlt-1 did not show any statistically significant differences, as was the case for the rest of the herein examined growth factors. CONCLUSIONS: In this study, we observed higher levels of sFlt-1 mRNA expression in the placenta of spontaneous abortions, while expression of other growth factors in placenta and decidua remained constant. This suggests that an imbalance of sFlt-1 expression in the placenta might contribute to the pathogenesis of spontaneous abortion, probably via oxidative stress, providing a possible biomarker for prompt identification of this condition.

Co-expression of fibrotic genes in inflammatory bowel disease; A localized event?

Introduction: Extracellular matrix turnover, a ubiquitous dynamic biological process, can be diverted to fibrosis. The latter can affect the intestine as a serious complication of Inflammatory Bowel Diseases (IBD) and is resistant to current pharmacological interventions. It embosses the need for out-of-the-box approaches to identify and target molecular mechanisms of fibrosis. Methods and results: In this study, a novel mRNA sequencing dataset of 22 pairs of intestinal biopsies from the terminal ileum (TI) and the sigmoid of 7 patients with Crohn's disease, 6 with ulcerative colitis and 9 control individuals (CI) served as a validation cohort of a core fibrotic transcriptomic signature (FIBSig), This signature, which was identified in publicly available data (839 samples from patients and healthy individuals) of 5 fibrotic disorders affecting different organs (GI tract, lung, skin, liver, kidney), encompasses 241 genes and the functional pathways which derive from their interactome. These genes were used in further bioinformatics co-expression analyses to elucidate the site-specific molecular background of intestinal fibrosis highlighting their involvement, particularly in the terminal ileum. We also confirmed different transcriptomic profiles of the sigmoid and terminal ileum in our validation cohort. Combining the results of these analyses we highlight 21 core hub genes within a larger single co-expression module, highly enriched in the terminal ileum of CD patients. Further pathway analysis revealed known and novel inflammation-regulated, fibrogenic pathways operating in the TI, such as IL-13 signaling and pyroptosis, respectively. Discussion: These findings provide a rationale for the increased incidence of fibrosis at the terminal ileum of CD patients and highlight operating pathways in intestinal fibrosis for future evaluation with mechanistic and translational studies.

Is serum gentamicin concentration modified with autologous cell-saved blood transfusion after total knee arthroplasty using tranexamic acid? A randomised control trial.

BACKGROUND: Self-transfusion has been proven as an effective management of blood loss after total knee arthroplasty (TKA). Considering that the high local concentration of antibiotic from bone cement is delivered intravenously through the self-transfusion process, systematic toxicity has never been evaluated. In addition, the effectiveness of self-transfusion with the routine concomitant use of other modern blood-salvage strategies, like tranexamic acid, should also be assessed. Therefore, we performed a randomised study to assess: 1) the safety of self-transfusion in TKA by comparing the gentamicin concentrations resulting from the use or not of autologous blood transfusion; 2) the efficacy of self-transfusion in TKA, with the concomitant administration of tranexamic acid. HYPOTHESIS: Self-transfusion in TKA elevates the serum gentamicin concentration and the potential risk of nephrotoxicity. METHODS: The serum concentration of aminoglycosides was measured in two groups of 20 patients each, after TKA, according to the use of self-transfusion. Hemoglobin, renal function and calculated blood loss were compared at several points in time between groups. RESULTS: The only time where there was a statistically significant difference in serum gentamicin, was at 48h postoperatively between groups [0.3 ug/mL±0.21, range: 0.15 to 0.72 vs. 0.14ug/mL±0.1, range: 0 to 0.35 (p=0.02)]. There were no significant differences in total blood loss [1341mL±501, range: 830 to 2230 vs. 1263mL±459 range: 840 to 2480 (p=0.67)] and need of allogeneic blood transfusion [3 units vs. 2 units] between groups. CONCLUSION: The use of autologous blood transfusion was found to be safe, in terms of nephrotoxicity of aminoglycosides after TKA, but it seemed to be ineffective as a blood salvage strategy, when used concomitantly with the administration of tranexamic acid. LEVEL OF EVIDENCE: II; low-powered randomised study. CLINICALTRIALS. GOV REGISTRATION NUMBER: NCT04505748.

Gentamycin elution from polymethylmethacrylate and bone graft substitute: Comparison between commercially available and home-made preparations.

Polymethylmethacrylate (PMMA) represents the current gold standard as an antibiotic delivery carrier in orthopaedic surgery. Despite the accepted use of local antibiotic carriers, there aren't any conclusive data comparing PMMA to Bone Graft Substitutes. The aim of this in vitro study was to compare the elution profile of gentamicin from various preparations of PMMA cements and Herafill beads. All cements had high initial elution during the first hour which then slowly decreased, Herafill beads on the other hand showed its higher elution around the eighth hour. Herafill, in general, presented the highest elution of gentamicin regardless of its input amount.

Gut Microbial Signatures Underline Complicated Crohn's Disease but Vary Between Cohorts; An In Silico Approach.

Microflora dysbiosis is implicated in the pathophysiology of Crohn's disease. This work analyzes differences in microbial communities and relevant metabolic pathways among the nonstricturing nonpenetrating (B1), stricturing (B2), and penetrating (B3) subphenotypes of Crohn's disease vs healthy controls. We conducted a bioinformatics analysis using the QIIME pipeline and the Calypso, linear discriminant analysis effect size, Phylogenetic Investigation of Communities by Reconstruction of Unobserved States, and STAMP tools on publicly available 16S bacterial rRNA sequencing data from terminal ileum mucosal biopsies of healthy controls and the 3 subphenotypes of Crohn's disease. We analyzed differences in microbial diversity and taxonomy, inferred active metabolic pathways via relevant genes' abundance, and detected bacterial families that could serve as biomarkers. Microbiota α-diversity was decreased within all 3 Crohn's disease subphenotypes vs control samples, with more significant reductions in B2 and B3 compared with B1. ß-diversity analysis identified similar microbial patterns in B2 and B3 samples, different from those of B1 and from those of healthy controls. Abundance analysis of microbial families in cohorts, beyond altered abundances compared with healthy controls, highlighted significant differences between the B2 and B3 subphenotypes and the B1 subphenotype. A similar pattern was observed in the inference of microbial metabolomics: the B2 and B3 cohorts had different predicted metabolotypes from the B1 cohort, in addition to differences observed in Crohn's disease vs healthy controls. Our findings indicate distinct microbiome signatures in complicated Crohn's disease subphenotypes and provide the basis for further investigation into the role of gut microflora in the natural course of Crohn's disease.

The Length of Surgical Skin Incision in Postoperative Inflammatory Reaction.

BACKGROUND AND OBJECTIVES: Surgery provokes inflammatory and immune responses, so efforts have been made to reduce host response by using less invasive techniques. The purpose of this experimental study was to investigate the surgical stress induced by skin incision and the role of liver response in this process. METHODS: Seventy male anesthetized Wistar rats were subjected to a midline incision confined strictly to the skin (dermis) of either 1 cm long (n = 20), 10 cm long (n = 20), or no incision (n = 20) or served as controls (n = 10). Skin trauma was left open for a 20-minutes period, and then was meticulously sutured. At 3 and 24 hours later, laparotomy was performed on half the rats of each group, for blood and liver sampling. In serum and liver homogenates, cytokine-induced neutrophil chemoattractant (CINC)1/interleukin (IL)-8 and tumor necrosis factor (TNF)-α levels were measured with enzyme-linked immunosorbent assays and nitric oxide (NO) using a Griess reaction. RESULTS: Skin trauma was found to significantly (P < .01) increase all inflammatory mediators tested (CINC1/IL-8, TNF-α, NO) in serum of operated rats versus controls, the increase being proportionally dependent on the length of skin incision. In liver homogenates, CINC1/IL-8 was significantly (P < .01) increased in operated animals versus controls, similarly to serum levels. In contrast, liver TNF-α levels were inversely related to serum levels, and a significant (P < .01) decrease in TNF-α was observed in liver homogenates of operated animals compared with the controls, indicating that the increased TNF-α in blood reflects liver TNF-α secretion. CONCLUSION: Our findings suggest that inflammatory and immune reactions induced by skin-only surgical trauma are closely correlated to the length of skin incision.

Cytokine Receptor Profiling in Human Colonic Subepithelial Myofibroblasts: A Differential Effect of Th Polarization-Associated Cytokines in Intestinal Fibrosis.

Background: Colonic subepithelial myofibroblasts (cSEMFs) are mesenchymal cells with a pivotal role in the pathophysiology of Crohn's disease (CD) fibrosis. Here, we demonstrate for the first time a complete expression mapping of cytokine receptors, implicated in inflammatory bowel diseases, in primary human cSEMFs and how pro-inflammatory cytokines regulate this expression. Furthermore, we show the effect of Th1-, Th2-, Th17- and Treg-related cytokines on a fibrosis-related phenotype of cSEMFs. Methods: Colonic subepithelial myofibroblasts were isolated from healthy individuals' colonic biopsies. Interleukin (IL)-1α- and/or tumor necrosis factor (TNF)-α-induced mRNA and protein expression of cytokine receptors was assayed by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunofluorescence, respectively. Th-related cytokine effects on mRNA and protein profibrotic factor expression were analyzed by qRT-PCR and/or colorimetric assays and on the wound-healing capacity of cSEMFs by scratch test. Results: In cSEMFs, we observed basal cytokine receptor expression, which was modified by IL-1α and TNF-α. Th1-related cytokines upregulated tissue factor (TF), collagen, fibronectin and matrix metalloproteinase (MMP)-1 and downregulated α-smooth muscle actin (α-SMA), MMP-9, and wound healing rate. Th2-related cytokines upregulated collagen, TF, α-SMA, MMP-1, and wound healing rate and downregulated fibronectin and MMP-9. IL-17 and IL-23 upregulated fibronectin, and IL-22 downregulated TF. IL-17 and IL-22 decreased wound healing rate. Similar to TGF-ß, IL-23 upregulated MMP-1, tissue inhibitor of metalloproteinases-1, collagen expression, and wound healing rates. Conclusions: Our results suggest that cSEMFs have a central role in inflammation and fibrosis, as they express a great variety of Th-related cytokine receptors, making them responsive to pro-inflammatory cytokines, abundant in the inflamed mucosa of CD patients.

Lung fibrosis-associated soluble mediators and bronchoalveolar lavage from idiopathic pulmonary fibrosis patients promote the expression of fibrogenic factors in subepithelial lung myofibroblasts.

Idiopathic pulmonary fibrosis (IPF) is characterized by infiltration of inflammatory cells, excessive collagen production and accumulation of myofibroblasts. We explored the possible role of subepithelial lung myofibroblasts (SELMs) in the development of fibrosis in IPF. SELMs, isolated from surgical specimens of healthy lung tissue, were cultured with pro-inflammatory factors or bronchoalveolar lavage fluid (BALF) from patients with IPF or idiopathic non-specific interstitial pneumonia (iNSIP) and their fibrotic activity was assessed. Stimulation of SELMs with pro-inflammatory factors induced a significant increase of Tissue Factor (TF) and Tumor necrosis factor-Like cytokine 1 A (TL1A) expression and collagen production in culture supernatants. Stimulation with BALF from IPF patients with mild to moderate, but not severe disease, and from iNSIP patients induced a significant increase of TF expression. BALF from all IPF patients induced a significant increase of TL1A expression and collagen production, while BALF from iNSIP patients induced a significant increase of TL1A, but not of collagen production. Interestingly, TGF-ß1 and BALF from all IPF, but not iNSIP patients, induced a significant increase in SELMs migration. In conclusion, BALF from IPF patients induces fibrotic activity in lung myofibroblasts, similar to mediators associated with lung fibrosis, indicating a key role of SELMs in IPF.

Crohn's disease-associated mucosal factors regulate the expression of TNF-like cytokine 1A and its receptors in primary subepithelial intestinal myofibroblasts and intestinal epithelial cells.

Intestinal subepithelial myofibroblasts (SEMFs) exert a profibrotic role in Crohn's disease (CD). Tumor necrosis factor-like cytokine 1A (TL1A) and its receptors, death-domain receptor 3 (DR3) and decoy receptor 3 (DcR3), are mucosal factors with significant involvement in experimental inflammation and CD. We aimed to determine the regulation of expression of this system of proteins in SEMFs and intestinal epithelial cells. The relative amount of mRNA transcripts for TL1A, DR3, and DcR3 was measured by real-time reverse transcription polymerase chain reaction in cultured primary SEMFs, colonic myofibroblast cell line 18CO, and epithelial cell line HT29. Protein expression was determined by immunofluorescence. The effect of various proinflammatory stimuli in mRNA and protein expression was studied. TL1A mRNA and protein expression in primary SEMFs (and 18CO cells) was significantly upregulated after stimulation with interleukin 1-alpha and/or tumor necrosis factor alpha (TNF-α) (32- to 44-fold increase, P < 0.05 vs unstimulated). Following stimulation with interleukin 1-alpha + TNF-α + IFN-γ, HT-29 cells highly expressed DR3 (4.1-fold over unstimulated, P = 0.008) and DcR3 (56-fold, P = 0.009) and secreted soluble factors that led to induction of TL1A mRNA in primary SEMFs (28-fold, P = 0.008). Activated epithelial cells significantly upregulated IL-8 expression in response to stimulation with recombinant TL1A. Supernatants from mucosal cultures of patients with CD were able to stimulate the expression of TL1A in cultured primary SEMFs, in comparison to supernatants from healthy controls (3.8-fold increase, P < 0.05) or culture media alone (P < 0.05). In conclusion, we found that proinflammatory cytokines are important regulators of the expression of TL1A in SEMFs and of its receptors in intestinal epithelial cells. Our results raise the possibility for involvement of TL1A/DR3/DR3-mediated mechanisms in epithelial-mesenchymal interactions and the development of inflammation-induced intestinal fibrosis in CD.

Intraperitoneal application of phospholipids for the prevention of postoperative adhesions: a possible role of myofibroblasts.

BACKGROUND: Peritoneal adhesions, organized as fibrous bands after abdominal surgery, are related with considerable morbidity and repeated hospitalization. Phospholipids, natural constituents of the peritoneal fluid, seem to display excellent antiadhesive properties. The aim of this study was to investigate whether intraperitoneal application of phospholipids is capable of reducing postoperative adhesions and the possible underlying mechanisms. MATERIALS AND METHODS: Twenty male Wistar rats were subjected to a midline laparotomy and a standard peritoneal and cecum abrasion trauma. Before laparotomy closure, a bolus of 3 mL of phospholipids (12 mg/mL) or NaCl (placebo) was given intraperitoneally. Seven days later, the quality and the quantity of adhesions, as well as serum proinflammatory and/or profibrotic mediators, were blindly assessed. Human colonic subepithelial myofibroblasts were isolated from normal controls and cultured with transforming growth factor-ß1 (TGFß1, 5 ng/mL) in the presence of phospholipids (30-300 µg/mL). Collagen production in culture supernatants and migratory activity of myofibroblasts were also assessed. RESULTS: Phospholipids reduced intra-abdominal adhesions (P < 0.001), with respect to their intensity and area, and serum levels of cytokines (interleukin 1ß, interleukin 6, platelet-derived growth factor-1, and TGFß1) compared with placebo-treated rats. Stimulation of myofibroblasts with TGFß1 significantly increased (P < 0.001) the basic collagen production. The presence of phospholipids significantly reduced (P < 0.001) both the TGFß1 induced and the basic collagen production. Using a wound healing assay, phospholipids were found to reduce the basic and the TGFß1-induced migration of myofibroblasts in a concentration-dependent manner. CONCLUSIONS: Intraperitoneal phospholipids might be involved in the prevention of postoperative adhesions formation via the reduction of proinflammatory and/or profibrotic mediators and by inhibiting fibrogenic properties of mesenchymal cells.

Low-dose clarithromycin therapy modulates Th17 response in non-cystic fibrosis bronchiectasis patients.

INTRODUCTION: Th17 cells play a crucial role in neutrophilic inflammation and tissue injury in non-cystic fibrosis (non-CF) bronchiectasis. Clarithromycin demonstrates anti-inflammatory and immunomodulatory properties but the effect of long-term clarithromycin prophylaxis on the Th17 response in non-CF bronchiectasis is still unexplored. METHODS: Th17 response was studied in 22 patients with stable non-CF bronchiectasis receiving daily 500-mg clarithromycin for 12 weeks. We analysed IL-17 concentrations in exhaled breath condensate (EBC) and peripheral blood Th17 cells, whereas functional parameters and clinical data were recorded in parallel. RESULTS: Both, post-treatment absolute counts of CD4+IL17+ cells in peripheral blood and IL-17 levels in EBC decreased significantly (post-treatment CD4+IL17+ mean 2.418 ± 0.414 cells/µl versus pre-treatment 3.202 ± 0.507 cells/µl, p = 0.036 and post-treatment IL-17 mean levels 7.16 ± 0.47 pg/ml versus pre-treatment 9.32 ± 0.47 pg/ml, p < 0.001, respectively). Post-treatment EBC IL-17 levels decreased significantly in both patients who exhibited exacerbations and those who remained stable during the study period (mean 6.72 ± 0.37 versus 9.12 ± 0.64 pg/ml, p = 0.01 and 7.69 ± 0.9 versus 9.53 ± 0.72 pg/ml, p = 0.042, respectively), while pre-treatment and post-treatment levels did not differ between the two groups (p = 0.665 and p = 0.465, respectively). PaO(2) improved significantly (post-treatment mean 77.73 ± 2.23 mmHg versus pre-treatment 73.18 ± 2.22 mmHg, p = 0.025), while PaCO(2), post-bronchodilation FEV1, and post-bronchodilation FVC remained unaltered. CONCLUSIONS: Our results argue for a reduction of both systemic and local Th17 response after prophylactic, low-dose clarithromycin administration in patients with non-CF bronchiectasis, suggestive of a potential anti-inflammatory and/or immunomodulatory action.

Low expression of interferon regulatory factor-1 and identification of novel exons skipping in patients with chronic myeloid leukaemia.

Chronic myeloid leukaemia (CML) is a malignant clonal disorder of the haematopoietic stem cell. Treatment of CML patients with interferon alpha (IFN-alpha) has induced haematological and cytogenetic remission. Interferons transcriptionally activate target genes through the JAK-STAT and interferon regulated factors (IRFs) family pathways. Interferon regulated factor-1 (IRF-1) is a transcriptional activator of genes critical for cell growth, differentiation and apoptosis. The skipping of exons 2 or 2 and 3 of IRF-1 in patients with myelodysplastic syndromes and acute myelogenous leukaemia suggests that this factor may have a critical role in leukaemogenesis. The role of IRF-1 in CML is currently unknown. Therefore, mutational analysis of IRF-1 was performed and its expression pattern was also studied in CML patients. We studied IRF-1 in peripheral blood mononuclear cells of 21 patients in chronic phase CML. No point mutations were identified at the cDNA level. Surprisingly, fourfold reduction of full-length IRF-1 mRNA expression was established in 17/21 patients compared with normal individuals. Low expression of full-length IRF-1 was observed in conjunction with high levels of aberrantly spliced mRNAs, reported for the first time. In three patients who were also analysed during blastic transformation, further reduction of full-length IRF-1 mRNA was observed. These findings demonstrate that, in CML patients, IRF-1 can produce high levels of aberrant spliced mRNAs with subsequent reduction in the levels of full-length IRF-1 mRNA. This observation is consistent with the notion that exon skipping may constitute another mechanism of tumour suppressor gene inactivation in this disease.