Heparin-binding epidermal growth factor-like growth factor (HB-EGF) activates p38 to affect pulmonary fibrosis.

Objective: We aimed to examine whether heparin-binding epidermal growth factor-like growth factor (HB-EGF) affects the lung fibrosis process through the activation of p38 protein in mitogen-activated protein kinases (MAPK) signaling pathway, as well as the expression of downstream inflammatory factors. Methods: The expression levels of HB-EGF, collagen type I (COL-I), and hexokinase 2 (HK2) in peripheral blood mononuclear cells (PBMCs) of patients with connective tissue disease-related interstitial lung disease (CTD-ILD) were examined by qPCR, Western blotting and ELISA. Results: In vitro experiments showed that HB-EGF was increased in almost all subtypes [rheumatoid arthritis (RA), systemic sclerosis (SSc) and idiopathic inflammatory myopathies (IIMs)] as well as in all groups (P < 0.05). For embryonic lung fibroblast (A549) cells, the expression levels of HK2 and α-smooth muscle actin (α-SMA) genes were elevated during 0-4 h and then plateaued. Transforming growth factor-ß1 (TGF-ß1) induced fibrosis in human embryonic lung fibroblasts (MRC-5) cells and A549 for a certain period of time, but the degree of induction varied, which may be related to the redifferentiability of cells at different spatial locations. Moreover, HB-EGF at concentrations above 1 ng/ml stimulation increased COL-I expression (P < 0.05), and for α-SMA gene, even 1 ng/ml concentration of HB-EGF had a stimulatory effect, and different concentrations of HB-EGF did activate the expression of p38 in a concentration-dependent manner within a certain concentration range, and by The qPCR results showed that for interleukin 6 (IL-6), an inflammatory factor regulated downstream of p38, the expression was significantly increased in A549 cells compared to control (P < 0.05), but tumor necrosis factor-α (TNF-α) expression was downregulated (P < 0.05), but for interleukin-1ß (IL-1ß) gene, there was no significant difference in A549 cells, and expression was downregulated in MRC-5 cells. Therefore, it is suggested that HB-EGF regulates the expression of inflammatory factors through p38 will be differential across cells. Conclusion: Our study shows that HB-EGF can suppress pulmonary fibrosis through downstream activation of p38/MAPK pathway activity, as well as the expression of various inflammatory factors downstream of it.

Phenotypes of patients with systemic sclerosis in the Chinese Han population: a cluster analysis.

OBJECTIVE: Systemic sclerosis (SSc) is a heterogeneous connective tissue disease that is commonly subdivided into limited cutaneous SSc (lcSSc) and diffuse cutaneous SSc (dcSSc) based on the extent of skin involvement. This subclassification may not reflect the full range of clinical phenotypic variation. This study aimed to investigate clinical features and aggregation of patients with SSc in Chinese based on SSc manifestations and organ involvements, in order to achieve precise treatment of SSc early prevention of complications. METHODS: In total 287 SSc patients were included in this study. A cluster analysis was applied according to 13 clinical and serologic variables to determine subgroups of patients. Survival rates between obtained clusters and risk factors affecting prognosis were also compared. RESULT: In this study, six clusters were observed: cluster 1 (n = 66) represented the skin type, with all patients showing skin thickening. In cluster 2 (n = 56), most patients had vascular and articular involvement. Cluster 3 (n = 14) individuals mostly had cardiac and pulmonary involvement. In cluster 4 (n = 52), the gastrointestinal type, 50 patients presented with stomach symptoms and 28 patients presented with esophageal symptoms. In cluster 5 (n = 50), patients barely had any major organ involvement. Cluster 6 (n = 49) included 46% of all patients presenting with renal crisis. CONCLUSION: The results of our cluster analysis study implied that limiting SSc patient subgroups to those based only on skin involvement might not capture the full heterogeneity of the disease. Organ damage and antibody profiles should be considered when identifying homogeneous patient groups with a specific prognosis. Key Points • Provides a new method of categorizing SSc patients. • Can better explain disease progression and guide subsequent treatment.

Anti-carbamylated protein antibodies drive AEC II toward a profibrotic phenotype by interacting with carbamylated TLR5.

OBJECTIVES: This study was to explore the role of Anti-carbamylated protein (Anti-CarP) antibodies in contributing to lung fibrosis in connective tissue disease (CTD)-associated interstitial lung disease (ILD) in an autoantigen-dependent manner. METHODS: ELISA tested serum samples, including 89 of CTD-ILD group and 170 of non-ILD CTD, for the anti-CarP levels. Male C57BL/6 mice were used for pulmonary fibrosis model and anti-CarP treatment in vivo (n = 5), and patient serum-derived or commercialized anti-CarP for cell treatment. We identified the carbamylated membrane protein via immunofluorescence (IF) and coimmunoprecipitation followed by mass spectrometry (MS) analysis. RT-qPCR, IF and western blot were performed to explore the antigen-dependent role of anti-CarP. Native electrophoretic mobility shift assay and MS analysis were used to verify direct interaction and carbamylation sites. RESULTS: A significantly higher serum anti-CarP level was observed in CTD with ILD than without ILD. In vivo, intrapulmonary delivery of anti-CarP induces epithelial-mesenchymal transition (EMT) and micro fibrotic foci. Carbamylation was enriched in type II alveolar epithelial cells (AEC II). A novel carbamylated membrane receptor, specifically recognized by anti-CarP, was identified as toll-like receptor 5 (TLR5). We found anti-CarP induces the nuclear translocation of NF-κB and downstream events, including EMT and expression of inflammatory cytokines in AEC II, which were reversed by TLR5 blocking or TLR5 knockdown. Moreover, up to 12 lysine carbamylation sites were found in TLR5 ectodomain, allowing the interaction of anti-CarP with carbamylated TLR5. CONCLUSIONS: Overall, we found anti-CarP drives aberrant AEC II activation by interacting with carbamylated TLR5 to promote ILD progress.

Elevated platelet-to-lymphocyte ratio and neutrophil-to-lymphocyte ratio in patients with polymyositis/dermatomyositis: a retrospective study.

OBJECTIVES: This study aimed to examine the diagnostic and prognostic value of the platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR) in patients with polymyositis/dermatomyositis (PM/DM). METHOD: Clinical data of 200 patients with PM/DM and 204 healthy controls were retrospectively reviewed. We examined whether the PLR and NLR were associated with PM/DM. RESULTS: The PLR and NLR were higher in patients with PM/DM than in controls (both P < 0.001). The PLR and NLR were higher in patients with DM than in those with PM (both P < 0.01). The PLR was higher in the anti-melanoma differentiation-associated protein-5 (anti-MDA5) + PM/DM group than in the anti-MDA5- PM/DM group (P = 0.002). The NLR in non-survivors was higher than that in survivors (P = 0.01). The NLR was positively correlated with the occurrence of interstitial lung disease (ILD). The PLR and NLR were independent predictors of PM/DM, as well as risk factors (both P < 0.001). Moreover, the NLR had a predictive value for PM/DM-ILD and was closely related to mortality (P = 0.033, P = 0.003, respectively). CONCLUSIONS: Patients with PM/DM have a higher NLR and PLR than healthy controls, especially in those with anti-MDA5+. The PLR and NLR are independent risk factors for PM/DM and have some predictive value. The NLR is correlated with ILD and associated with an increased risk of mortality in patients with PM/DM. The NLR and PLR may be simple, economical, and accurate diagnostic and prognostic markers for patients with PM/DM. Key points • The neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) have been studied in numerous inflammatory diseases as potential markers, but their clinical significance in polymyositis/dermatomyositis (PM/DM) remains unclear. • We examined the changes in the NLR and PLR between patients with PM/DM and healthy controls, as well as their association with mortality, interstitial lung disease, and anti-melanoma differentiation-associated protein-5. • Patients with PM/DM may benefit from using the NLR and PLR as simple, economical, and accurate diagnostic and prognostic markers.

Neutrophil extracellular traps and pulmonary fibrosis: an update.

Pulmonary fibrosis (PF) is a serious and often fatal illness that occurs in various clinical settings and represents a significant unmet medical need. Increasing evidence indicates that neutrophil extracellular traps (NETs) contribute significantly to the progression of PF. Therefore, understanding the pathways by which NETs contribute to the disease is crucial for developing effective treatments. This review focuses on the formation of NETs and the common mechanisms of NETs in PF.