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Borghuis, T.

Publications and source records attributed to Borghuis, T..

5 recordsLinked to original sources

IL-11 disrupts alveolar epithelial progenitor function

IL-11 is linked to the pathogenesis of idiopathic pulmonary fibrosis (IPF), since IL-11 induces myofibroblast differentiation and stimulates their excessive collagen deposition in the lung. The alveolar architecture is disrupted in IPF, yet the effect of IL-11 on dysregulated alveolar repair associated with IPF remains to be elucidated. We hypothesized that epithelial-fibroblast communication associated with lung repair is disrupted by IL-11. Thus, we studied whether IL-11 affects the repair responses of alveolar lung epithelium using mouse lung organoids and precision cut lung slices (PCLS). Additionally, we assessed the anatomical distribution of IL-11 and IL-11 receptor in human control and IPF lungs using immunohistochemistry. IL-11 protein was observed in human control lungs in airway epithelium, macrophages and in IPF lungs, in areas of AT2 cell hyperplasia. IL-11R staining was predominantly present in smooth muscle and macrophages. In mouse organoid co-cultures of epithelial cells with lung fibroblasts, IL-11 decreased organoid number and reduced the fraction of pro-SPC expressing organoids, indicating dysfunctional regeneration initiated by epithelial progenitors. In mouse PCLS alveolar marker gene expression declined, whereas airway markers were increased. The response of primary human fibroblasts to IL-11 on gene expression level was minimal, though bulk RNA-sequencing revealed IL-11 modulated a number of processes which may play a role in IPF, including unfolded protein response, glycolysis and Notch signaling. In conclusion, IL-11 disrupts alveolar epithelial regeneration by inhibiting progenitor activation and suppressing the formation of mature alveolar epithelial cells. The contribution of dysregulated fibroblast - epithelial communication to this process appears to be limited.

cell biology↗

Substrate stiffness engineered to replicate disease conditions influence senescence and fibrotic responses in primary lung fibroblasts

In idiopathic pulmonary fibrosis (IPF) there is excessive ECM deposition, increased stiffness and ultimately destruction of lung parenchyma. IPF presents mainly in the elderly, implying that senescence, a hallmark of ageing, contributes to disease progression. Several studies have reported that IPF is characterised by increased senescence and accumulating evidence suggests that structural changes, such as increased stiffness may contribute to senescence. This study therefore investigated if increased tissue stiffness could modulate markers of senescence and/or fibrosis in primary lung fibroblasts. Using hydrogels representing healthy and fibrotic stiffnesses, we cultured primary fibroblasts from non-diseased lung tissue on top of these hydrogels for up to seven days before assessing senescence and fibrosis markers. Fibroblasts cultured on stiff ({+/-}15kPa) hydrogels showed higher Yes-associated protein-1 (YAP) nuclear translocation compared to soft hydrogels. When looking at senescence-associated proteins we also found higher secretion of receptor activator of nuclear factor kappa-B ligand (RANKL) but no change in transforming growth factor-{beta}1 (TGF-{beta}1) or connective tissue growth factor (CTGF) expression and higher decorin protein deposition on stiff matrices. With respect to genes associated with fibrosis, fibroblasts on stiff hydrogels compared to soft had higher expression of smooth muscle alpha ()-2 actin (ACTA2), collagen (COL) 1A1 and fibulin-1 (Fbln1) and higher Fbln1 protein deposition after seven days. Our results show that exposure of lung fibroblasts to fibrotic stiffness activates genes and secreted factors that are part of fibrotic responses and part of the senescence-associated secretory profile (SASP). This overlap may contribute to the creation of a feedback loop whereby fibroblasts create a perpetuating cycle reinforcing disease progression in IPF.

cell biology↗

Age-associated Differences in the Human Lung Extracellular Matrix

IntroductionExtracellular matrix (ECM) remodelling has been associated with chronic lung diseases. However, information about specific age-associated differences in lung ECM is currently limited. In this study we aimed to identify and localize age-associated ECM differences in human lung using comprehensive transcriptomic, proteomic and immunohistochemical analyses. MethodsOur previously identified age-associated gene expression signature of the lung was re-analysed limiting it to an aging signature based on 270 control patients (37-80 years) and focused on the Matrisome core geneset using geneset enrichment analysis. To validate the age-associated transcriptomic differences on protein level, we compared the age-associated ECM genes (F <0.05) with a profile of age-associated proteins identified from a lung tissue proteomics dataset from 9 control patients (49-76 years) (FDR<0.05). Extensive immunohistochemical analysis was used to localize the age-associated ECM differences in lung tissues from control patients (9-82 years). ResultsComparative analysis of transcriptomic and proteomic data identified 7 ECM proteins with higher expression with age at both gene and protein level: COL1A1, COL6A1, COL6A2, COL14A1, FBLN2, LTBP4 and LUM. With immunohistochemistry we demonstrated higher protein expression with age for COL6A2 in whole tissue, parenchyma, airway wall and blood vessel, for COL14A1 in bronchial epithelium and blood vessel, and for FBLN2 and COL1A1 in lung parenchyma. ConclusionOur study revealed that higher age is associated with lung ECM remodelling, with specific differences occurring in defined regions within the lung. These differences may affect lung structure and physiology with aging and as such may increase susceptibility for developing chronic lung diseases. Key messagesO_ST_ABSWhat is already known on this topicC_ST_ABSsummarise the state of scientific knowledge on this subject before you did your study and why this study needed to be done. In animal models, it has been demonstrated that aging alters the composition of the lung ECM, with more deposition of collagen and degradation of elastin. Similar ECM differences have been observed in age-associated chronic lung diseases, including COPD; moreover, we observed in lung tissue that several ECM genes associate differently with age in COPD patients compared to non-COPD controls(1). Detailed knowledge on age-associated changes in specific ECM proteins as well as regional differences within the lung is lacking. What this study addssummarise what we now know as a result of this study that we did not know before. We identified 7 age-associated ECM proteins i.e. COL1A1, COL6A1, COL6A2 COL14A1, FBLN2, LTBP4 and LUM with higher transcript and protein levels in human lung tissue with age. Extensive immunohistochemical analysis revealed significant age-associated differences for 3 of these ECM proteins in specific compartments of the lung, with the most notable differences in the blood vessels and parenchyma. How this study might affect research, practice, or policysummarise the implications of this study. The identification of age-associated differences in specific human lung ECM proteins lays a new foundation for the investigation of ECM differences in age-associated chronic lung diseases. Additionally, examining the function of these age-associated ECM proteins and their cellular interactions in lung injury and repair responses may provide novel insight in mechanisms underlying chronic lung diseases.

molecular biology↗

An in vitro model of fibrosis using crosslinked native extracellular matrix-derived hydrogels to modulate biomechanics without changing composition

Extracellular matrix (ECM) is a dynamic network of proteins, proteoglycans and glycosaminoglycans, providing structure to the tissue and biochemical and biomechanical instructions to the resident cells. In fibrosis, the composition and the organization of the ECM are altered, and these changes influence cellular behaviour. Biochemical (i. e. protein composition) and biomechanical changes in ECM take place simultaneously in vivo. Investigating these changes individually in vitro to examine their (patho)physiological effects has been difficult. In this study, we generated an in vitro model to reflect the altered mechanics of a fibrotic microenvironment through applying fibre crosslinking via ruthenium/sodium persulfate crosslinking on native lung ECM-derived hydrogels. Crosslinking of the hydrogels without changing the biochemical composition of the ECM resulted in increased stiffness and decreased viscoelastic stress relaxation. The altered stress relaxation behaviour was explained using a generalized Maxwell model. Fibre analysis of the hydrogels showed that crosslinked hydrogels had a higher percentage of matrix with a high density and a shorter average fibre length. Fibroblasts seeded on ruthenium-crosslinked lung ECM-derived hydrogels showed myofibroblastic differentiation with a loss of spindle-like morphology together with greater -smooth muscle actin (-SMA) expression, increased nuclear area and circularity without any decrease in the viability, compared with the fibroblasts seeded on the native lung-derived ECM hydrogels. In summary, ruthenium crosslinking of native ECM-derived hydrogels provides an exciting opportunity to alter the biomechanical properties of the ECM-derived hydrogels while maintaining the protein composition of the ECM to study the influence of mechanics during fibrotic lung diseases.

pathology↗

Osteoprotegerin is elevated in pulmonary fibrosis and associates with IPF progression

Osteoprotegerin (OPG), a decoy receptor for receptor activator of NF-kB ligand (RANKL), is used as a biomarker for assessing severity of liver fibrosis. However, its expression and role in pulmonary fibrosis are unknown. We hypothesized that OPG also has a role in pulmonary fibrosis. Human and mouse control and fibrotic lung tissue were used to examine OPG expression, and mouse precision-cut lung slices to study OPG regulation in pulmonary fibrosis. Serum from idiopathic pulmonary fibrosis (IPF) patients and controls was analysed to investigate whether OPG levels correlate with disease status as measured by lung function. OPG-protein levels were significantly higher in mouse and human fibrotic lung tissue compared to control. OPG-mRNA and protein production were induced in mouse precision-cut-lung slices upon TGF{beta} stimulation and could be inhibited with galunisertib, a TGF{beta} receptor kinase inhibitor. OPG-protein levels in fibrotic mouse lung tissue correlated with degree of fibrosis. Isolated lung fibroblasts from IPF patients had higher OPG-protein levels than control fibroblasts. Serum OPG levels in IPF patients, at first presentation, negatively correlated with diffusing capacity to carbon monoxide. Finally, serum OPG levels higher than 1234 pg/ml at first presentation were associated with progression of disease in IPF patients. In conclusion, OPG is produced in lung tissue, associates with fibrosis, and may be a potential prognostic biomarker for IPF disease progression. Validation in a larger cohort is warranted to further explore the role of OPG in pulmonary fibrosis and its potential for assessing the prognosis of fibrotic lung disease in individual patients. Take home messageOsteoprotegerin is present in fibrotic lung tissue and high serum levels correlate with low lung function and IPF disease progression in this small study, indicating osteoprotegerin may have value as a biomarker to predict IPF progression

pathology↗