MMP3 and lung fibrosis

An increase in MMP3 was found in IPF lung tissue. Mmmp3–/– mice were protected from bleomycin induced lung fibrosis, through beta-catenin mediated EMT.


References:
Am J Pathol. 2011 Oct;179(4):1733-45. Epub 2011 Aug 24.
Matrix metalloproteinase 3 is a mediator of pulmonary fibrosis.
Yamashita CM, Dolgonos L, Zemans RL, Young SK, Robertson J, Briones N, Suzuki T, Campbell MN, Gauldie J, Radisky DC, Riches DW, Yu G, Kaminski N, McCulloch CA, Downey GP.
Source
Department of Medicine, University of Western Ontario, London, Ontario, Canada; Division of Pulmonary and Critical Care Medicine, Departments of Medicine and Pediatrics, National Jewish Health, Denver, Colorado.
Abstract
Idiopathic pulmonary fibrosis (IPF) may be triggered by epithelial injury that results in aberrant production of growth factors, cytokines, and proteinases, leading to proliferation of myofibroblasts, excess deposition of collagen, and destruction of the lung architecture. The precise mechanisms and key signaling mediators responsible for this aberrant repair process remain unclear. We assessed the importance of matrix metalloproteinase-3 (MMP-3) in the pathogenesis of IPF through i) determination of MMP-3 expression in patients with IPF, ii) in vivo experiments examining the relevance of MMP-3 in experimental models of fibrosis, and iii) in vitro experiments to elucidate possible mechanisms of action. Gene expression analysis, quantitative RT-PCR, and Western blot analysis of explanted human lungs revealed enhanced expression of MMP-3 in IPF, compared with control. Transient adenoviral vector-mediated expression of recombinant MMP-3 in rat lung resulted in accumulation of myofibroblasts and pulmonary fibrosis. Conversely, MMP-3-null mice were protected against bleomycin-induced pulmonary fibrosis. In vitro treatment of cultured lung epithelial cells with purified MMP-3 resulted in activation of the β-catenin signaling pathway, via cleavage of E-cadherin, and induction of epithelial-mesenchymal transition. These processes were inhibited in bleomycin-treated MMP-3-null mice, as assessed by cytosolic translocation of β-catenin and cyclin D1 expression. These observations support a novel role for MMP-3 in the pathogenesis of IPF, through activation of β-catenin signaling and induction of epithelial-mesenchymal transition.
Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.
PMID: 21871427 [PubMed - in process] PMCID: PMC3181358 [Available on 2012/10/1]

Plasma proteins predict IPF

With a cohort of 241 IPF patients, a recent study found that high concentrations of MMP7, ICAM1, IL8, VCAM1, and S100A12 predicted poor overall survival, poor transplant free survival and poor progression free survival in the derivation cohort.



References:
Am J Respir Crit Care Med. 2011 Oct 20. [Epub ahead of print]
Peripheral Blood Proteins Predict Mortality in Idiopathic Pulmonary Fibrosis.
Richards TJ, Kaminski N, Baribaud F, Flavin S, Brodmerkel C, Horowitz D, Li K, Choi J, Vuga LJ, Lindell KO, Klesen M, Zhang Y, Gibson KF.
Source
Medicine/PACCM, University of Pittsburgh, Pittsburgh, Pennsylvania, United States.
Abstract
Introduction/

BACKGROUND:
Idiopathic pulmonary fibrosis (IPF) is a lethal lung disease of unknown etiology with a variable and unpredictable course. The aim of this study was to identify and validate plasma proteins that are predictive of outcome in IPF.

METHODS:
Plasma samples were available for 241 IPF patients (140 - derivation and 101 validation). In derivation cohort, concentrations of 92 proteins were analyzed using a multiplex bead-based immunoassay and concentrations of MMP7, MMP1, and SPD were assessed by ELISA. In the validation cohort concentrations of ICAM1, IL8, VCAM1 were assessed by bead-based multiplex assay, and S100A12 and MMP7 by ELISA. Associations of biomarkers with mortality, transplant free survival, and disease progression were tested in derivation and validation cohorts using nonparametric methods of survival analysis and the Cox proportional hazards model, and an integrated risk prediction score was derived and tested.

RESULTS:
High concentrations of MMP7, ICAM1, IL8, VCAM1, and S100A12 predicted poor overall survival, poor transplant free survival and poor progression free survival in the derivation cohort. In the independent validation cohort high concentrations of all five were predictive of poor transplant free survival, MMP7, ICAM1, and IL8 of overall survival and ICAM1 of poor progression free survival. The personal clinical and molecular mortality prediction index (PCMI) derived in the derivation cohort was highly predictive of mortality in the validation cohort.

CONCLUSIONS:
Our results suggest that plasma proteins should be evaluated as a tool for prognosis determination in prioritization of patients for lung transplantation and stratification in drug studies.

PMID: 22016448 [PubMed - as supplied by publisher]

Annexin A1 and lung fibrosis

Annexin A1 is upregulated in epithelial cells and inflammatory cells. In AnxA1 null mice, there were increased inflammation and fibrosis after bleomycin. There was also an increase in TGFbeta, IFN-gamma, and TNF-a.
The study suggests a protective role for endogenous Annexin A1 in lung fibrosis.

References:
BMC Immunol. 2011 Oct 19;12(1):59. [Epub ahead of print]
Endogenous annexin A1 counter-regulates bleomycin-induced lung fibrosis.
Damazo AS, Sampaio AL, Nakata CM, Flower RJ, Perretti M, Oliani SM.
Abstract
ABSTRACT:

BACKGROUND:
The balancing functions of pro/anti-inflammatory mediators of the complex innate responses have been investigated in a variety of experimental inflammatory settings. Annexin-A1 (AnxA1) is one mediator of endogenous anti-inflammation, affording regulation of leukocyte trafficking and activation in many contexts, yet its role in lung pathologies has been scarcely investigated, despite being highly expressed in lung cells. Here we have applied the bleomycin lung fibrosis model to AnxA1 null mice over a 21-day time-course, to monitor potential impact of this mediator on the control of the inflammatory and fibrotic phases.

RESULTS:
Analyses in wild-type mice revealed strict spatial and temporal regulation of the Anxa1 gene, e.g. up-regulation in epithelial cells and infiltrated granulocytes at day 7, followed by augmented protein levels in alveolar macrophages by day 21. Absence of AnxA1 caused increases in: i) the degree of inflammation at day 7; and ii) indexes of fibrosis (assessed by deposition of hydroxyproline in the lung) at day 7 and 21. These alterations in AnxA1 null mice were paralleled by augmented TGF-beta1, IFN-gamma and TNF-alpha generation compared to wild-type mice. Finally, treatment of wild type animals with an AnxA1 peptido-mimetic, given prophylactically (from day 0 to 21) or therapeutically (from day 14 onward), ameliorated both signs of inflammation and fibrosis.

CONCLUSION:
Collectively these data reveal a pathophysiological relevance for endogenous AnxA1 in lung inflammation and, more importantly, fibrosis, and may open new insights for the pharmacological treatment of lung fibrosis.

PMID: 22011168 [PubMed - as supplied by publisher]

Tight junction protein Claudin-5 and lung fibrosis

Am J Physiol Lung Cell Mol Physiol. 2011 Oct 14. [Epub ahead of print]
Altered expression of tight junction molecules in alveolar septa in lung injury and fibrosis.
Ohta H, Chiba S, Ebina M, Furuse M, Nukiwa T.
Source
1Tohku University Graduate school of Medicine.
Abstract
The dysfunction of alveolar barriers is a critical factor in the development of lung injury and subsequent fibrosis, but the underlying molecular mechanisms remain poorly understood. To clarify the pathogenic roles of tight junctions in lung injury and fibrosis, we examined the altered expression of claudins, the major components of tight junctions, in the lungs of disease models with pulmonary fibrosis. Among the 24 known claudins, claudin-1, claudin-3, claudin-4, claudin-7, and claudin-10 were identified as components of airway tight junctions. Claudin-5 and claudin-18 were identified as components of alveolar tight junctions and were expressed in endothelial and alveolar epithelial cells, respectively. In experimental bleomycin-induced lung injury, the levels of mRNA encoding tight junction proteins were reduced, particularly that of claudin-18. The integrity of the epithelial tight junctions was disturbed in the fibrotic lesions 14 days after the intraperitoneal instillation of bleomycin. These results suggest that bleomycin mainly injured alveolar epithelial cells and impaired alveolar barrier function. In addition, we analyzed the influence of transforming growth factor-β (TGF-β), a critical mediator of pulmonary fibrosis that is upregulated after bleomycin-induced lung injury, on tight junctions in vitro. The addition of TGF-β decreased the expression of claudin-5 in human umbilical vein endothelial cells (HUVECs) and disrupted the tight junctions of epithelial cells (A549). These results suggest that bleomycin-induced lung injury causes pathogenic alterations in tight junctions and that such alterations seem to be induced by TGF-β.

PMID: 22003091 [PubMed - as supplied by publisher]

SPARC in lung fibrosis

A recent study with bone marrow chimera mice suggested that, bleomycin induces inflammation and fibrosis in wild type through TNF synthesis that triggers TGF-β release; TGF-β promotes fibroblasts deposition and regulates TNF synthesis from macrophages.

B: In WT>SPARC KO chimeras, despite a normal parenchyma inflammation, collagen deposition by fibroblasts is greatly reduced and results in milder fibrosis.

C: In SPARC KO>WT chimeras, the inability of SPARC KO macrophages to down-modulate TNF production in response to TGF-β results in exaggerated and persistent inflammation and severe fibrosis.


Reference
Am J Pathol. 2011 Oct 11. [Epub ahead of print]
SPARC Oppositely Regulates Inflammation and Fibrosis in Bleomycin-Induced Lung Damage.
Sangaletti S, Tripodo C, Cappetti B, Casalini P, Chiodoni C, Piconese S, Santangelo A, Parenza M, Arioli I, Miotti S, Colombo MP.
Source
Molecular Immunology Unit, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale Tumori, Milan, Italy.
Abstract
Fibrosis results from inflammatory tissue damage and impaired regeneration. In the context of bleomycin-induced pulmonary fibrosis, we demonstrated that the matricellular protein termed secreted protein acidic and rich in cysteine (SPARC) distinctly regulates inflammation and collagen deposition, depending on its cellular origin. Reciprocal Sparc(-/-) and wild-type (WT) bone marrow chimeras revealed that SPARC expression in host fibroblasts is required and sufficient to induce collagen fibrosis in a proper inflammatory environment. Accordingly, Sparc(-/-) WT chimeras showed exacerbated inflammation and fibrosis due to the inability of Sparc(-/-) macrophages to down-regulate tumor necrosis factor production because of impaired responses to tumor growth factor-β. Hence, the use of bone marrow cells expressing a dominant-negative form of tumor growth factor-β receptor type II under the monocyte-specific CD68 promoter, as a decoy, phenocopied Sparc(-/-) donor chimeras. Our results point to an unexpected dual role of SPARC in oppositely influencing the outcome of fibrosis.
Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.
PMID: 22001347 [PubMed - as supplied by publisher]

CD69 and lung fibrosis

CD69-/- mice exhibited reduced inflammation and fibrosis.

Reference:
Respir Res. 2011 Oct 5;12(1):131. [Epub ahead of print]
Attenuation of lung inflammation and fibrosis in CD69-deficient mice after intratracheal bleomycin.
Yamauchi K, Kasuya Y, Kuroda F, Tanaka K, Tsuyusaki J, Ishizaki S, Matsunaga H, Iwamura C, Nakayama T, Tatsumi K.
Abstract
ABSTRACT:

BACKGROUND:
Cluster of differentiation 69 (CD69), an early activation marker antigen on T and B cells, is also expressed on activated macrophages and neutrophils, suggesting that CD69 may play a role in inflammatory diseases. To determine the effect of CD69 deficiency on bleomycin(BLM)-induced lung injury, we evaluated the inflammatory response following intratracheal BLM administration and the subsequent fibrotic changes in wild type (WT) and CD69-deficient (CD69-/-) mice.

METHODS:
The mice received a single dose of 3 mg/kg body weight of BLM and were sacrificed at 7 or 14 days post-instillation (dpi). Lung inflammation in the acute phase (7 dpi) was investigated by differential cell counts and cytokine array analyses of bronchoalveolar lavage fluid. In addition, lung fibrotic changes were evaluated at 14 dpi by histopathology and collagen assays. We also used reverse transcription polymerase chain reaction to measure the mRNA expression level of transforming growth factor beta1 (TGF-beta1) in the lungs of BLM-treated mice.

RESULTS:
CD69-/- mice exhibited less lung damage than WT mice, as shown by reductions in the following indices: (1) loss of body weight, (2) wet/dry ratio of lung, (3) cytokine levels in BALF, (4) histological evidence of lung injury, (5) lung collagen deposition, and (6) TGF-beta1 mRNA expression in the lung.

CONCLUSION:
The present study clearly demonstrates that CD69 plays an important role in the progression of lung injury induced by BLM.

PMID: 21970554 [PubMed - as supplied by publisher] Free

Immunoglobulin free light chains are increased in hypersensitivity pneumonitis and IPF

from PLoSOne
PLoS One. 2011;6(9):e25392. Epub 2011 Sep 28.
Immunoglobulin free light chains are increased in hypersensitivity pneumonitis and idiopathic pulmonary fibrosis.
Groot Kormelink T, Pardo A, Knipping K, Buendía-Roldán I, García-de-Alba C, Blokhuis BR, Selman M, Redegeld FA.
Source
Division of Pharmacology and Pathophysiology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Utrecht, The Netherlands.
Abstract
BACKGROUND:
Idiopathic pulmonary fibrosis (IPF), a devastating lung disorder of unknown aetiology, and chronic hypersensitivity pneumonitis (HP), a disease provoked by an immunopathologic reaction to inhaled antigens, are two common interstitial lung diseases with uncertain pathogenic mechanisms. Previously, we have shown in other upper and lower airway diseases that immunoglobulin free light chains (FLCs) are increased and may be involved in initiating a local inflammation. In this study we explored if such a mechanism may also apply to HP and IPF.

METHODS:
In this study we examined the presence of FLC in serum and BAL fluid from 21 IPF and 22 HP patients and controls. IgG, IgE and tryptase concentrations were measured in BAL fluid only. The presence of FLCs, plasma cells, B cells and mast cells in lung tissue of 3 HP and 3 IPF patients and 1 control was analyzed using immunohistochemistry.

RESULTS:
FLC concentrations in serum and BAL fluid were increased in IPF and HP patients as compared to control subjects. IgG concentrations were only increased in HP patients, whereas IgE concentrations were comparable to controls in both patient groups. FLC-positive cells, B cells, plasma cells, and large numbers of activated mast cells were all detected in the lungs of HP and IPF patients, not in control lung.

CONCLUSION:
These results show that FLC concentrations are increased in serum and BAL fluid of IPF and HP patients and that FLCs are present within affected lung tissue. This suggests that FLCs may be involved in mediating pathology in both diseases.

PMID: 21980441 [PubMed - in process] PMCID: PMC3182208