Platelets stimulate fibroblast-mediated contraction of collagen gels

BACKGROUND: Platelets are thought to play a role in a variety of inflammatory conditions in the lung, some of which may lead to fibrosis. In the current study we tested the hypothesis that whole platelets and platelet lysate can mediate remodelling of extracellular matrix in vitro by affecting fibroblast-mediated contraction of a collagen gel. We also sought to determine to what extent platelet-derived growth factor (PDGF) and transforming growth factor-β (TGF-β) contribute to this effect. METHODS: Washed platelets, isolated from healthy blood donors, and platelet lysate (freezing and thawing), were cast together with human lung fibroblasts in three-dimensional collagen gels. The gels were then released and cultured for four days. PDGF and TGF-β(1 )concentrations were measured in culture supernatants by ELISA. RESULTS: Both platelets and platelet lysate augmented fibroblast-mediated gel contraction in a time and concentration dependent manner (19.9% ± 0.1 (mean ± SEM) of initial area vs. 48.0% ± 0.4 at 48 hours; P < 0.001 and 41.5% ± 0.6 vs. 60.6% ± 0.3 at 48 hours; P < 0.001, respectively). Fixed platelets had no effect in the system. Both TGF-β(1 )and PDGF-AA/AB were released in co-culture. PDGF-AA/AB had a maximum release at 24 hours whereas TGF-β(1 )release increased with longer culture periods. Neutralising antibodies to these mediators partially inhibited platelet-induced gel contraction. CONCLUSION: We conclude that platelets may promote remodelling of extracellular matrix in vitro and that PDGF and TGF-β partially mediate this effect, also indicating a role for other mediators. The findings may be an important mechanism in regulating repair processes after injury

Helicobacter pylori infection, chronic corpus atrophic gastritis and pancreatic cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort: a nested case-control study

The association between H. pylori infection and pancreatic cancer risk remains controversial. We conducted a nested case-control study with 448 pancreatic cancer cases and their individually matched control subjects, based on the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, to determine whether there was an altered pancreatic cancer risk associated with H. pylori infection and chronic corpus atrophic gastritis. Conditional logistic regression models were applied to calculate odds ratios (ORs) and corresponding 95% confidence intervals (CIs), adjusted for matching factors and other potential confounders. Our results showed that pancreatic cancer risk was neither associated with H. pylori seropositivity (OR = 0.96; 95% CI: 0.70, 1.31) nor CagA seropositivity (OR = 1.07; 95% CI: 0.77, 1.48). We also did not find any excess risk among individuals seropositive for H. pylori but seronegative for CagA, compared with the group seronegative for both antibodies (OR = 0.94; 95% CI: 0.63, 1.38). However, we found that chronic corpus atrophic gastritis was non-significantly associated with an increased pancreatic cancer risk (OR = 1.35; 95% CI: 0.77, 2.37), and although based on small numbers, the excess risk was particularly marked among individuals seronegative for both H. pylori and CagA (OR = 5.66; 95% CI: 1.59, 20.19, p value for interaction < 0.01). Our findings provided evidence supporting the null association between H. pylori infection and pancreatic cancer risk in western European populations. However, the suggested association between chronic corpus atrophic gastritis and pancreatic cancer risk warrants independent verification in future studies, and, if confirmed, further studies on the underlying mechanisms

Efficacy of Loop-Mediated Isothermal Amplification for H. pylori Detection as Point-of-Care Testing by Noninvasive Sampling

For targeted eradication of Helicobacter pylori (H. pylori) to reduce gastric cancer burden, a convenient approach is definitely needed. The purpose of this study was to evaluate the LAMP assay for H. pylori detection using samples collected by noninvasive and self-sampling methods. The available LAMP assay for H. pylori detection was appraised and verified using reference and clinically isolated H. pylori strains. In addition, a clinical study was conducted to assess the LAMP assay on 51 patients, from whom saliva, oral brushing samples, feces, corpus, and antrum specimens were available. Clarithromycin resistance was also analysed through detection of A2143G mutation using the LAMP-RFLP method. The validation and verification analysis demonstrated that the LAMP assay had an acceptable result in terms of specificity, sensitivity, reproducibility, and accuracy for clinical settings. The LAMP assay showed a detection limit for H. pylori down to 0.25 fg/µL of genomic DNA. An acceptable consensus was observed using saliva samples (sensitivity 58.1%, specificity 84.2%, PPV 85.7%, NPV 55.2%, accuracy 68%) in comparison to biopsy sampling as the gold standard. The performance testing of different combinations of noninvasive sampling methods demonstrated that a combination of saliva and oral brushing could achieve a sensitivity of 74.2% and a specificity of 57.9%. A2143G mutation detection by LAMP-RFLP showed perfect consensus with Sanger sequencing results. It appears that the LAMP assay in combination with noninvasive and self-sampling as a point-of-care testing (POCT) approach has potential usefulness to detect H. pylori infection in clinic settings and screening programs

Pirfenidone and nintedanib modulate properties of fibroblasts and myofibroblasts in idiopathic pulmonary fibrosis

Abstract Background Idiopathic pulmonary fibrosis (IPF) is an incurable lung disease with a poor prognosis. Fibroblasts and myofibroblasts are the key cells in the fibrotic process. Recently two drugs, pirfenidone and nintedanib, were approved for clinical use as they are able to slow down the disease progression. The mechanisms by which these two drugs act in in vitro cell systems are not known. The aim of this study was therefore to examine the effects of pirfenidone and nintedanib on fibroblasts and myofibroblasts structure and function established from patients with or without IPF. Methods Stromal cells were collected and cultured from control lung (n = 4) or IPF (n = 7). The cells were treated with pirfenidone and/or nintedanib and the effect of treatment was evaluated by measuring cell proliferation, alpha smooth muscle actin (α-SMA) and fibronectin expression by Western analysis and/or immunoelectron microscopy, ultrastructural properties by transmission electron microscopy and functional properties by collagen gel contraction and invasion assays. Results Both pirfenidone and nintedanib reduced in vitro proliferation of fibroblastic cells in a dose dependent manner. The number of cells from control lung was reduced to 47 % (p = 0.04) and of IPF cells to 42 % (p = 0.04) by 1 mM pirfenidone and correspondingly to 67 % (p = 0.04) and 68 % (p = 0.04), by 1 μM nintedanib. If both drugs were used together, a further reduced proliferation was observed. Both pirfenidone and nintedanib were able to reduce the amount of α-SMA and the myofibroblastic appearance although the level of reduction was cell line dependent. In functional assays, the effect of both drugs was also variable. Conclusions We conclude that the ultrastructure and function of fibroblasts and myofibroblasts are affected by pirfenidone and nintedanib. Combination of the drugs reduced cell proliferation more than either of them individually. Human lung derived cell culture systems represent a potential platform for screening and testing drugs for fibrotic diseases

Additional file 2: of Pirfenidone and nintedanib modulate properties of fibroblasts and myofibroblasts in idiopathic pulmonary fibrosis

Proliferation assay performed in collagen gel contraction assay conditions. In these conditions the cells are not proliferating. Serum was used as a positive control to induce the proliferation. (PDF 178 kb

Additional file 1: of Pirfenidone and nintedanib modulate properties of fibroblasts and myofibroblasts in idiopathic pulmonary fibrosis

Proliferation of TGFβ1 induced stromal cells by pirfenidone (A, B) and by nintedanib (C, D). Six samples were analysed and 3 of them were derived from healthy lung (A, C) and 3 from IPF (B, D). Pirfenidone (0.1 mM-1 mM) or nintedanib (0.1-1 μM) was added to the sample together with 5 ng/ml TGFβ1 at the beginning of the experiment. The values were related to the corresponding control. (PDF 257 kb

Helicobacter pylori infection, chronic corpus atrophic gastritis and pancreatic cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort: a nested case-control study

The association between H. pylori infection and pancreatic cancer risk remains controversial. We conducted a nested case-control study with 448 pancreatic cancer cases and their individually matched control subjects, based on the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, to determine whether there was an altered pancreatic cancer risk associated with H. pylori infection and chronic corpus atrophic gastritis. Conditional logistic regression models were applied to calculate odds ratios (ORs) and corresponding 95% confidence intervals (CIs), adjusted for matching factors and other potential confounders. Our results showed that pancreatic cancer risk was neither associated with H. pylori seropositivity (OR = 0.96; 95% CI: 0.70, 1.31) nor CagA seropositivity (OR = 1.07; 95% CI: 0.77, 1.48). We also did not find any excess risk among individuals seropositive for H. pylori but seronegative for CagA, compared with the group seronegative for both antibodies (OR = 0.94; 95% CI: 0.63, 1.38). However, we found that chronic corpus atrophic gastritis was non-significantly associated with an increased pancreatic cancer risk (OR = 1.35; 95% CI: 0.77, 2.37), and although based on small numbers, the excess risk was particularly marked among individuals seronegative for both H. pylori and CagA (OR = 5.66; 95% CI: 1.59, 20.19, p value for interaction < 0.01). Our findings provided evidence supporting the null association between H. pylori infection and pancreatic cancer risk in western European populations. However, the suggested association between chronic corpus atrophic gastritis and pancreatic cancer risk warrants independent verification in future studies, and, if confirmed, further studies on the underlying mechanisms