CXCR4+ cells are increased in lung tissue of patients with idiopathic pulmonary fibrosis.
ABSTRACT: BACKGROUND:CXCR4, a transmembrane-receptor located on epithelial cells that is activated by CXCL12, may have a role in IPF via migration of CXCR4+ fibrocytes to the lung. However, its expression has not been fully characterised in idiopathic pulmonary fibrosis (IPF) or other fibrotic interstitial lung diseases (ILDs). CXCL12 is constitutively expressed in the bone marrow, and levels of CXCR4 regulate control of this signalling pathway. The aim of this study was to profile the expression of CXCR4 in lung tissue and peripheral circulation of patients with IPF and other fibrotic ILDs. METHODS:Expression of CXCR4 on peripheral blood mononuclear cells (PBMCs) was examined by flow cytometry in 20 patients with IPF and 10 age-matched non-disease control (NDC) donors. Levels of CXCL12 in human plasma were measured by ELISA. Expression of CXCR4, CXCL12, CD45, and e-cadherin was assessed in IPF (n?=?10), other fibrotic ILD (n?=?8) and NDC (n?=?10) lung tissue by multiplex immunohistochemistry (OPAL) and slides were scanned using a Vectra 3 scanner. Cells were quantified with computer automated histological analysis software (HALO). RESULTS:In blood, the number of CXCR4+ cells was lower but the level of CXCL12 was higher in patients with IPF compared to NDC donors. Elevated CXCR4 expression was detected in lung tissue from patients with IPF and other fibrotic ILDs compared to NDC. There were higher levels of CXCR4+/e-cadherin+/CXCL12+ (epithelial) cells in IPF lung tissue compared to NDC, but there was no difference in the numbers of CXCR4+/CD45+/CXCL12+ (myeloid) cells between the two groups. CONCLUSIONS:This report demonstrates that CXCR4 is overexpressed not only in IPF but also in other ILDs and expression is particularly prominent within both honeycomb cysts and distal airway epithelium. This observation supports the hypothesis that CXCR4 may drive tissue fibrosis through binding its specific ligand CXCL12. Although CXCR4 expressing cells could be either of epithelial or myeloid origin it appears that the former is more prominent in IPF lung tissue. Further characterization of the cells of the honeycomb cyst may lead to a better understanding of the fibrogenic processes in IPF and other end-stage fibrotic ILDs.
Project description:Idiopathic pulmonary fibrosis (IPF) is a chronic fibrotic lung disease that is prevalent in individuals >50 years of age, with a median survival of 3-5 years and limited therapeutic options. The disease is characterized by collagen deposition and remodeling of the lung parenchyma in a process that is thought to be driven by collagen-expressing immune and structural cells. The G-protein coupled C-X-C chemokine receptor 4, CXCR4, is a candidate therapeutic target for IPF owing to its role in the recruitment of CXCR4+ fibrocytes from the bone marrow to fibrotic lung tissue and its increased expression levels by structural cells in fibrotic lung tissue. We have engineered a novel fully human single domain antibody "i-body" called AD-114 that binds with high affinity to human CXCR4. We demonstrate here that AD-114 inhibits invasive wound healing and collagen 1 secretion by human IPF fibroblasts but not non-diseased control lung fibroblasts. Furthermore, in a murine bleomycin model of pulmonary fibrosis, AD-114 reduced the accumulation of fibrocytes (CXCR4+/Col1+/CD45+) in fibrotic murine lungs and ameliorated the degree of lung injury. Collectively, these studies demonstrate that AD-114 holds promise as a new biological therapeutic for the treatment of IPF.
Project description:A proportion of patients with fibrosing interstitial lung diseases (ILDs) develop a progressive phenotype characterised by decline in lung function, worsening quality of life and early mortality. Other than idiopathic pulmonary fibrosis (IPF), there are no approved drugs for fibrosing ILDs and a poor evidence base to support current treatments. Fibrosing ILDs with a progressive phenotype show commonalities in clinical behaviour and in the pathogenic mechanisms that drive disease worsening. Nintedanib is an intracellular inhibitor of tyrosine kinases that has been approved for treatment of IPF and has recently been shown to reduce the rate of lung function decline in patients with ILD associated with systemic sclerosis (SSc-ILD). In vitro data demonstrate that nintedanib inhibits several steps in the initiation and progression of lung fibrosis, including the release of pro-inflammatory and pro-fibrotic mediators, migration and differentiation of fibrocytes and fibroblasts, and deposition of extracellular matrix. Nintedanib also inhibits the proliferation of vascular cells. Studies in animal models with features of fibrosing ILDs such as IPF, SSc-ILD, rheumatoid arthritis-ILD, hypersensitivity pneumonitis and silicosis demonstrate that nintedanib has anti-fibrotic activity irrespective of the trigger for the lung pathology. This suggests that nintedanib inhibits fundamental processes in the pathogenesis of fibrosis. A trial of nintedanib in patients with progressive fibrosing ILDs other than IPF (INBUILD) will report results in 2019.
Project description:Among the interstitial lung diseases (ILDs), idiopathic pulmonary fibrosis (IPF), chronic hypersensitivity pneumonitis, and fibrotic connective tissue disease-related ILD are associated with a worse prognosis, with death occurring as a result of both respiratory failure and serious associated comorbidities. The recent development and approval of the antifibrotic agents nintedanib and pirfenidone, both of which reduced the rate of decline in lung function in patients with IPF in clinical trials, offer hope that it may be possible to alter the increased mortality associated with IPF. Although chronic hypersensitivity pneumonitis and connective tissue disease related-ILD may be associated with an inflammatory component, the evidence for the use of immunosuppressive agents in their treatment is largely limited to retrospective studies. The lack of benefit of immunosuppressive therapy in advanced fibrosis argues for rigorous clinical trials using antifibrotic therapies in these types of ILD as well. Patients with fibrotic ILD may benefit from identification and management of associated comorbid conditions such as pulmonary hypertension, gastroesophageal reflux, and OSA, which may improve the quality of life and, in some cases, survival in affected individuals. Because early assessment may optimize posttransplantation outcomes, lung transplant evaluation should occur early in patients with IPF and those with other forms of fibrotic ILD.
Project description:Rationale:Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic interstitial lung disease, with high mortality. Currently, the aetiology and the pathology of IPF are poorly understood, with both innate and adaptive responses previously being implicated in the disease pathogenesis. Heat shock proteins (Hsp) and antibodies to Hsp in patients with IPF have been suggested as therapeutic targets and prognostic biomarkers, respectively. We aimed to study the relationship between the expression of Hsp72 and anti-Hsp72 antibodies in the BAL fluid and serum Aw disease progression in patients with IPF. Methods:A novel indirect ELISA to measure anti-Hsp72 IgG was developed and together with commercially available ELISAs used to detect Hsp72 IgG, Hsp72 IgGAM, and Hsp72 antigen, in the serum and BALf of a cohort of IPF (n = 107) and other interstitial lung disease (ILD) patients (n = 66). Immunohistochemistry was used to detect Hsp72 in lung tissue. The cytokine expression from monocyte-derived macrophages was measured by ELISA. Results:Anti-Hsp72 IgG was detectable in the serum and BALf of IPF (n = 107) and other ILDs (n = 66). Total immunoglobulin concentrations in the BALf showed an excessive adaptive response in IPF compared to other ILDs and healthy controls (p = 0.026). Immunohistochemistry detection of C4d and Hsp72 showed that these antibodies may be targeting high expressing Hsp72 type II alveolar epithelial cells. However, detection of anti-Hsp72 antibodies in the BALf revealed that increasing concentrations were associated with improved patient survival (adjusted HR 0.62, 95% CI 0.45-0.85; p = 0.003). In vitro experiments demonstrate that anti-Hsp72 complexes stimulate macrophages to secrete CXCL8 and CCL18. Conclusion:Our results indicate that intrapulmonary anti-Hsp72 antibodies are associated with improved outcomes in IPF. These may represent natural autoantibodies, and anti-Hsp72 IgM and IgA may provide a beneficial role in disease pathogenesis, though the mechanism of action for this has yet to be determined.
Project description:Idiopathic pulmonary fibrosis (IPF) is a disease characterized by the accumulation of apoptosis-resistant fibroblasts in the lung. We have previously shown that high expression of the transcription factor Twist1 may explain this prosurvival phenotype in vitro. However, this observation has never been tested in vivo. We found that loss of Twist1 in COL1A2+ cells led to increased fibrosis characterized by very significant accumulation of T cells and bone marrow-derived matrix-producing cells. We found that Twist1-null cells expressed high levels of the T cell chemoattractant CXCL12. In vitro, we found that the loss of Twist1 in IPF lung fibroblasts increased expression of CXCL12 downstream of increased expression of the noncanonical NF-?B transcription factor RelB. Finally, blockade of CXCL12 with AMD3100 attenuated the exaggerated fibrosis observed in Twist1-null mice. Transcriptomic analysis of 134 IPF patients revealed that low expression of Twist1 was characterized by enrichment of T cell pathways. In conclusion, loss of Twist1 in collagen-producing cells led to increased bleomycin-induced pulmonary fibrosis, which is mediated by increased expression of CXCL12. Twist1 expression is associated with dysregulation of T cells in IPF patients. Twist1 may shape the IPF phenotype and regulate inflammation in fibrotic lung injury.
Project description:Radiological pleuroparenchymal fibroelastosis (PPFE) lesion is characterized by pleural thickening with associated signs of subpleural fibrosis on high-resolution computed tomography (HRCT). This study evaluated the clinical significance of radiological PPFE as an isolated finding or associated with other interstitial lung diseases (ILDs) in patients having fibrotic ILDs and registered for cadaveric lung transplantation (LT).This retrospective study included 118 fibrotic ILD patients registered for LT. Radiological PPFE on HRCT was assessed. The impact of radiological PPFE on clinical features and transplantation-censored survival were evaluated.Radiological PPFE was observed in 30/118 cases (25%): definite PPFE (PPFE concentrated in the upper lobes, with involvement of lower lobes being less marked) in 12 (10%) and consistent PPFE (PPFE not concentrated in the upper lobes, or PPFE with features of coexistent disease present elsewhere) in 18 (15%). Of these, 12 had late-onset non-infectious pulmonary complications after hematopoietic stem-cell transplantation and/or chemotherapy (LONIPCs), 9 idiopathic PPFE, and 9 other fibrotic ILDs (idiopathic pulmonary fibrosis, IPF; other idiopathic interstitial pneumonias, other IIPs; connective tissue disease-associated ILD, CTD-ILD, and hypersensitivity pneumonia, HP). Radiological PPFE was associated with previous history of pneumothorax, lower body mass index, lower percentage of predicted forced vital capacity (%FVC), higher percentage of predicted diffusion capacity of carbon monoxide, less desaturation on six-minute walk test, and hypercapnia. The median survival time of all study cases was 449 days. Thirty-seven (28%) received LTs: cadaveric in 31 and living-donor lobar in six. Of 93 patients who did not receive LT, 66 (71%) died. Radiological PPFE was marginally associated with better survival after adjustment for age, sex, %FVC, and six-minute walk distance <?250 m (hazard ratio 0.51 [0.25-1.05], p?=?0.07). After adjustment for covariates, idiopathic PPFE and LONIPC with radiological PPFE was associated with better survival than fibrotic ILDs without radiological PPFE (hazard ratio 0.38 [0.16-0.90], p?=?0.03), and marginally better survival than other fibrotic ILDs with radiological PPFE (hazard ratio, 0.20 [0.04-1.11], p?=?0.07).idiopathic PPFE and LONIPC with radiological PPFE has better survival on the wait list for LT than fibrotic ILDs without radiological PPFE, after adjustment for age, sex, %FVC, and six-minute walk distance.
Project description:Pulmonary fibrosis is characterized by the remodeling of fibrotic tissue and collagen deposition, which mainly results from aberrant fibroblasts proliferation and trans-differentiation to myofibroblasts. Patients with chronic myelogenous leukemia, myeloproliferative disorder, and scleroderma with pulmonary fibrosis complications show megakaryocyte infiltration in the lung. In this study, we demonstrated that the number of CD41+ megakaryocytes increased in bleomycin (BLM)-induced lung fibrosis tissues through the Chemokine (CXCmotif) ligand 12/Chemokine receptor 4 (CXCL12/CXCR4) axis. Pharmacological inhibition of the CXCL12/CXCR4 axis with WZ811 prevented migration of CD41+ megakaryocytes induced by BLM-injured lung tissue ex vivo and in vivo. In addition, WZ811 significantly attenuated lung fibrosis after BLM challenge. Moreover, megakaryocytes directly promoted fibroblast proliferation and trans-differentiation to myofibroblasts. We conclude that thrombopoietin (TPO) activated megakaryocytes through transforming growth factor β (TGF-β) pathway to promote fibroblast proliferation and trans-differentiation to myofibroblasts, which is abolished by treatment with selective TGF-βR-1/ALK5 inhibitors. Therefore, CD41+ megakaryocytes migrate to injured lung tissue partially through the CXCL12/CXCR4 axis to promote the proliferation and trans-differentiation of fibroblasts through direct contact and the TGF-β1 pathway.
Project description:Metastatic breast cancers (mBCs) are largely resistant to immune checkpoint blockade, but the mechanisms remain unclear. Primary breast cancers are characterized by a dense fibrotic stroma, which is considered immunosuppressive in multiple malignancies, but the stromal composition of breast cancer metastases and its role in immunosuppression are largely unknown. Here we show that liver and lung metastases of human breast cancers tend to be highly fibrotic, and unlike primary breast tumors, they exclude cytotoxic T lymphocytes (CTLs). Unbiased analysis of the The Cancer Genome Atlas database of human breast tumors revealed a set of genes that are associated with stromal T-lymphocyte exclusion. Among these, we focused on CXCL12 as a relevant target based on its known roles in immunosuppression in other cancer types. We found that the CXCL12 receptor CXCR4 is highly expressed in both human primary tumors and metastases. To gain insight into the role of the CXCL12/CXCR4 axis, we inhibited CXCR4 signaling pharmacologically and found that plerixafor decreases fibrosis, alleviates solid stress, decompresses blood vessels, increases CTL infiltration, and decreases immunosuppression in murine mBC models. By deleting CXCR4 in αSMA+ cells, we confirmed that these immunosuppressive effects are dependent on CXCR4 signaling in αSMA+ cells, which include cancer-associated fibroblasts as well as other cells such as pericytes. Accordingly, CXCR4 inhibition more than doubles the response to immune checkpoint blockers in mice bearing mBCs. These findings demonstrate that CXCL12/CXCR4-mediated desmoplasia in mBC promotes immunosuppression and is a potential target for overcoming therapeutic resistance to immune checkpoint blockade in mBC patients.
Project description:A proportion of patients with interstitial lung diseases (ILDs), including the ILDs that are commonly associated with autoimmune diseases, develop a progressive fibrosing phenotype characterised by worsening of lung function, dyspnoea and quality of life, and early mortality. No drugs are approved for the treatment of ILDs other than idiopathic pulmonary fibrosis (IPF). At present, immunomodulatory medications are the mainstay of treatment for non-IPF ILDs. However, with the exception of systemic sclerosis-associated ILD, the evidence to suggest that immunosuppression may preserve lung function in patients with these ILDs comes only from retrospective, observational, or uncontrolled studies. In this article, we review the evidence for the treatments currently used to treat ILDs associated with autoimmune diseases and other ILDs and the ongoing trials of immunosuppressant and antifibrotic therapies in patients with these ILDs.Funding: Boehringer Ingelheim.
Project description:The current study intends to investigate i) the incidence of herpes viruses including Herpes Simplex Virus type-1 (HSV-1), Cytomegalovirus (CMV) and Human Herpes Virus -6, -7, -8 (HHV6, HHV7, HHV8) in two biological samples, bronchoalveolar lavage fluid (BALF) and lung tissue biopsy, in different forms of pulmonary fibrosis, and ii) the induction of molecular pathways involved in fibrosis by herpesvirus infection in primary cell cultures. PCR was employed for the detection of CMV, HHV6-8 and HSV-1 DNA in lung specimens (4 controls and 11 IPF specimens) and BALF pellet [6 controls and 20 fibrotic Idiopathic Intestitial Pneumonias (f-IIPs) samples: 13 idiopathic pulmonary fibrosis (IPF) and 7 nonspecific idiopathic interstitial pneumonia (NSIP)] samples. Among all herpesviruses tested, HSV-1 was detected in 1/11 (9%) specimens from IPF lung tissue and in 2/20 (10%) samples of f-IIPs BALF whereas the control group was negative. Primary cell cultures from BALF of patients with IPF and healthy controls were infected in vitro with wild-type HSV-1 virus and Real Time PCR was employed for the detection of gene transcription of specific axes implicated in lung fibrosis. Primary cell cultures were permissive to HSV-1, resulting in an upregulation of the fibrotic growth factors TGF?1 and FGF, the angiogenetic markers SDF1a, SDF1b, VEGF, FGF and the regulators of tissue wound healing MMP9 and CCR7. Downregulation was noted for the CXCR4 and MMP2 genes, while a different response has been detected in healthy donors regarding the expression of the aforementioned markers. These results implicate for the first time the HSV-1 with Fibrotic Idiopathic Interstitial Pneumonias since the virus presented similar incidence in two different biological samples.