Idiopathic Interstitial Pneumonia Patients Research Articles

Anti-interferon gamma-inducible protein 16 antibodies: Identification of a novel autoantigen in idiopathic interstitial pneumonia and its clinical characteristics based on a multicenter cohort study

Autoantibodies are detected in idiopathic interstitial pneumonias (IIPs) without a clear connective tissue disease diagnosis, and their clinical significance is unclear. This study aimed to identify a novel autoantibody in IIPs. We screened 295 IIP patients using a 35S-methionine labeled protein immunoprecipitation assay. Candidate autoantigens were identified via protein array and confirmed by immunoprecipitation. Six sera from 295 IIP patients immunoprecipitated common tetrameric proteins (100 kDa). The protein array identified interferon gamma-inducible protein 16 (IFI16) as the candidate autoantigen. Patients with anti-IFI16 antibodies received immunosuppressants less frequently. Five-year survival rates were 50 %, 69 %, and 63 % (P = 0.60), and acute exacerbation-free rates were 50 %, 96 %, and 84 % (P = 0.15) for patients with anti-IFI16, anti-aminoacyl tRNA antibodies, and others. Anti-IFI16 is a novel autoantibody in IIPs. Patients with this antibody often receive less immunosuppressive therapy and could have a poor prognosis. Further research is needed to refine patient stratification and management.

Significance of Systemic Scleroderma-Specific Autoantibodies in Idiopathic Interstitial Pneumonia.

Objective Patients with idiopathic interstitial pneumonia (IIP) often test positive for systemic scleroderma-specific autoantibodies (SSc-Ab), even if they do not meet the diagnostic criteria for systemic scleroderma (SSc). However, the significance of SSc-Ab in IIP is unknown. Methods We retrospectively studied the medical records of all patients suspected of interstitial lung disease (ILD) who visited our center between January 2016 and December 2021. We evaluated the association between SSc-Ab subtypes and clinical characteristics, prognosis, and incidence of acute exacerbation (AE) of IIP. Among 571 patients suspected of having IIP and SSc-Ab measured, we excluded cases with clear causes of ILD or those diagnosed with other diseases and analyzed 386 cases diagnosed as IIP. Results Among 386 IIP patients, 48 were SSc-Ab positive (platelet-derived growth factor receptor (PDGFR) in 0, Th/To in 10, anti-nucleolar organizer region 90 antibodies (NOR90) in 12, fibrillarin in five, RP155 in 14, RP11 in three, CENP A in seven, CENP B in 10, and Scl-70 in six). There was no significant difference in survival rate or incidence of AE between patients with or without SSc-Ab. Multivariate logistic regression analysis showed that age and malignancy were significant risk factors for death, whereas age, male sex, and anti-fibrillarin antibodies were significant risk factors for AE of IIP. Conclusion None of the SSc-Abs were associated with the risk of mortality, and anti-fibrillarin antibodies, along with age and male sex may contribute to the risk of AE of IIP, predicting severe lung involvement and warranting multidisciplinary treatment and careful follow-up.

Proteomic profiling of bronchoalveolar lavage fluid uncovers protein clusters linked to survival in idiopathic forms of interstitial lung disease.

Idiopathic interstitial pneumonias (IIPs) such as idiopathic pulmonary fibrosis (IPF) and interstitial pneumonia with autoimmune features (IPAF), present diagnostic and therapeutic challenges due to their heterogeneous nature. This study aimed to identify intrinsic molecular signatures within the lung microenvironment of these IIPs through proteomic analysis of bronchoalveolar lavage fluid (BALF). Patients with IIP (n=23) underwent comprehensive clinical evaluation including pre-treatment bronchoscopy and were compared to controls without lung disease (n=5). Proteomic profiling of BALF was conducted using label-free quantitative methods. Unsupervised cluster analyses identified protein expression profiles which were then analyzed to predict survival outcomes and investigate associated pathways. Proteomic profiling successfully differentiated IIP from controls. k-means clustering, based on protein expression revealed three distinct IIP clusters, which were not associated with age, smoking history, or baseline pulmonary function. These clusters had unique survival trajectories and provided more accurate survival predictions than the Gender Age Physiology (GAP) index (C-index 0.794 vs. 0.709). The cluster with the worst prognosis featured decreased inflammatory signaling and complement activation, with pathway analysis highlighting altered immune response pathways related to immunoglobulin production and B cell-mediated immunity. The unsupervised clustering of BALF proteomics provided a novel stratification of IIP patients, with potential implications for prognostic and therapeutic targeting. The identified molecular phenotypes underscore the diversity within the IIP classification and the potential importance of personalized treatments for these conditions. Future validation in larger, multi-ethnic cohorts is essential to confirm these findings and to explore their utility in clinical decision-making for patients with IIP.

Progression to ANCA-associated vasculitis in patients with idiopathic interstitial pneumonia and positive ANCA

ObjectiveThis study explored the development of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and its risk factors in patients with idiopathic interstitial pneumonia (IIP) and positive ANCA results. MethodsData of patients diagnosed with IIP with positive ANCA results at a single tertiary center in South Korea were retrospectively reviewed from January 2013 to August 2023. Cox regression analysis was performed to identify variables associated with AAV occurrence following IIP diagnosis. Kaplan–Meier curves were employed to investigate the relationship between autoantibodies and the occurrence of AAV. ResultsIn a cohort of 154 IIP-diagnosed patients with positive ANCA results but without AAV, 10.4 % of them eventually developed AAV. The AAV and non-AAV groups did not significantly differ by sex, age, smoking status, urinalysis, or chest computed tomography findings. All the patients who subsequently developed AAV were anti-myeloperoxidase (MPO) positive, while 48.8 % of the non-AAV patients were anti-MPO positive (P < 0.001). Rheumatoid factor (RF) positivity differed significantly (62.5 % vs. 29.2 %, P = 0.007) between the AAV and non-AAV groups. Multivariate Cox regression and Kaplan–Meier analyses revealed RF (HR 4.02; P = 0.004) and anti-MPO (HR 38.10; P < 0.001) positivity as risk factors associated with AAV occurrence. ConclusionApproximately 10 % of ANCA-positive IIP patients developed AAV after an IIP diagnosis. Anti-MPO or co-occurring positive RF poses a significant risk for subsequent AAV occurrence. This emphasizes the importance of careful monitoring in patients with high-risk antibody profiles, even if the complete features of AAV are not present at IIP diagnosis.

Survival and acute exacerbation for patients with idiopathic pulmonary fibrosis (IPF) or non-IPF idiopathic interstitial pneumonias: 5-year follow-up analysis of a prospective multi-institutional patient registry

ObjectiveFew prospective cohort studies with relatively large numbers of patients with non-idiopathic pulmonary fibrosis (non-IPF) of idiopathic interstitial pneumonia (IIP) have been described. We aimed to assess disease progression and...

Nailfold capillaroscopy findings of interstitial pneumonia with autoimmune features.

We evaluated nailfold capillaroscopy (NFC) of interstitial pneumonia with autoimmune features (IPAF) and compared it with that of patients with connective tissue disease-interstitial lung disease (CTD-ILD) and idiopathic interstitial pneumonia (IIP). Patients with newly diagnosed as ILD were evaluated using NFC. Baseline demographic, clinical, serological, and high-resolution CT findings were collected. NFC was semi-quantitatively scored with six domains ranging from 0 to 18. In addition, the overall patterns (scleroderma/non-scleroderma patterns) were determined. A total of 81 patients (31 with CTD-ILD, 18 with IPAF, and 32 with IIP) were included. The non-specific interstitial pneumonia pattern was the most common ILD pattern in the CTD-ILD and IPAF groups, whereas the usual interstitial pneumonia pattern was the most common in the IIP group. The semi-quantitative score of the CTD-ILD group was higher than that of the IPAF or IIP groups (5.8 vs 4.2 vs 3.0, p < 0.001, respectively). Giant capillaries and haemorrhages were more frequently present in the CTD-ILD and IPAF groups than in the IIP group. A scleroderma pattern was present in 27.8% of the IPAF group, whereas none of the IIP patients showed a scleroderma pattern. NFC findings may be useful in classifying patients with ILD into CTD-ILD/IPAF/IIP.

A Retrospective Study of the Clinical, Radiological, and Pathological Characteristics of Patients with Interstitial Pneumonia Preceding Rheumatoid Arthritis.

Objective Interstitial lung disease (ILD) is the most critical manifestation in patients with rheumatoid arthritis (RA). In some cases, ILD may appear before the RA onset. Some patients with an initial diagnosis of idiopathic interstitial pneumonia (IIPs) develop RA; however, few studies have reported on its features, and the details remain unknown. In the present study, the clinical, radiological, and pathological features were evaluated in patients with ILD preceding RA. Methods The clinical, radiological, and pathological features of patients with ILD preceding RA were retrospectively reviewed using the medical records. Patients Ten patients with ILD preceding RA out of 883 IIP patients who underwent a surgical lung biopsy at our hospital from 2004 to 2018 were retrospectively examined. Results The median patient age was 59 (range 50-76) years old, and 7 of the patients were women. The median time from the ILD diagnosis to the RA onset was 50 (range 33-65) months. Regarding the high-resolution computed tomography pattern, the "indeterminate for UIP" pattern was the most popular, and cysts were seen in all cases. Attenuation around the cyst was prominent. Pathological findings showed plasma cell infiltration, bronchus-associated lymphoid tissue (BALT), and bronchiolitis in the lobules. Cellular and destructive bronchiolitis was noticeable in many patients with ILD preceding RA and contributed to the destruction and dilation of the bronchiole. Conclusion In ILD patients with IIP, radiological and pathological findings with increased attenuation around the cysts, prominent inflammatory cell infiltration (especially in plasma cells), an increase in the BALT number, and cellular and destructive bronchiolitis might serve as helpful RA development indicators.

Development of an Artificial Intelligence Model for Analyzing the Relationship between Imaging Features and Glucocorticoid Sensitivity in Idiopathic Interstitial Pneumonia.

High-resolution CT (HRCT) imaging features of idiopathic interstitial pneumonia (IIP) patients are related to glucocorticoid sensitivity. This study aimed to develop an artificial intelligence model to assess glucocorticoid efficacy according to the HRCT imaging features of IIP. The medical records and chest HRCT images of 150 patients with IIP were analyzed retrospectively. The U-net framework was used to create a model for recognizing different imaging features, including ground glass opacities, reticulations, honeycombing, and consolidations. Then, the area ratio of those imaging features was calculated automatically. Forty-five patients were treated with glucocorticoids, and according to the drug efficacy, they were divided into a glucocorticoid-sensitive group and a glucocorticoid-insensitive group. Models assessing the correlation between imaging features and glucocorticoid sensitivity were established using the k-nearest neighbor (KNN) algorithm. The total accuracy (ACC) and mean intersection over union (mIoU) of the U-net model were 0.9755 and 0.4296, respectively. Out of the 45 patients treated with glucocorticoids, 34 and 11 were placed in the glucocorticoid-sensitive and glucocorticoid-insensitive groups, respectively. The KNN-based model had an accuracy of 0.82. An artificial intelligence model was successfully developed for recognizing different imaging features of IIP and a preliminary model for assessing the correlation between imaging features and glucocorticoid sensitivity in IIP patients was established.

Positive Autoantibody Is Associated with Malignancies in Patients with Idiopathic Interstitial Pneumonias.

Various autoantibodies are associated with clinical outcomes in patients with idiopathic interstitial pneumonias (IIPs). We retrospectively analyzed the association between autoantibodies and malignancies in IIP patients. Comprehensive analyses of autoantibodies were performed using immunoprecipitation and enzyme-linked immunosorbent assays in 193 consecutive IIP patients. Cancer-related factors were analyzed using logistic regression analysis. In total, 22 of 193 patients (11.4%) with IIP had malignant disease. In univariate analysis, positivity for any autoantibody (odds ratio (OR), 3.1; 95% confidence interval (CI), 1.2–7.7; p = 0.017) and antinuclear antibody titer ≥1:320 (OR, 3.4; CI, 1.2–9.8; p = 0.024) were significantly associated with malignancies. Positive anti-aminoacyl tRNA synthetase (ARS) (OR, 3.7; CI, 0.88–15.5; p = 0.074) and anti-Ro52 antibody (OR, 3.2; CI, 0.93–11.2; p = 0.065) tended to be associated with malignancies. In multivariate analysis, independent risk factors were male sex (OR, 3.7; CI, 1.0–13.5; p = 0.029) and positivity for any autoantibody (OR, 3.9; CI, 1.5–10.1; p = 0.004) in model 1, and male sex (OR, 3.9; CI, 1.0–15.3; p = 0.049), antinuclear antibody titer ≥1:320 (OR, 4.2; CI, 1.4–13.3; p = 0.013), and positivity for anti-ARS antibody (OR, 6.5; CI, 1.2–34.1; p = 0.026) in model 2. Positivity for any autoantibody, antinuclear and anti-ARS antibodies, and male sex were independent risk factors for malignancies in IIP patients. Testing autoantibodies in IIP patients might help the early diagnosis of malignancies.

Clinical characteristics of idiopathic interstitial pneumonias with anti-Ro52/tripartite motif-containing 21 antibodies

Antibodies to Ro52/tripartite motif-containing 21 (TRIM21), referred to as anti-Ro52, are found in patients diagnosed with diverse systemic autoimmune rheumatic disease and associated with interstitial lung diseases. However, little is known about the clinical characteristics of anti-Ro52 in patients with idiopathic interstitial pneumonias (IIPs). We aimed to analyze the prevalence, co-existent autoantibodies, and clinical characteristics of anti-Ro52 in patients with IIP. The study enrolled 288 patients diagnosed with IIP. Clinical, laboratory and radiographic findings of IIP patients were compared between anti-Ro52 positives and negatives. Anti-Ro52 (20/288; 6.9%), anti-ARS (18/288; 6.3%), and anti-Ro60/SS-A (16/288; 5.6%) were the most common autoantibodies detected in IIP patients. Among 20 IIP patients who had anti-Ro52, anti-ARS was present in 8 (40%) patients. The criteria for interstitial pneumonia with autoimmune features (IPAF) were significantly better fulfilled by patients with anti-Ro52 than those without (P = 0.001). Meeting serological domain (P < 0.001) and Raynaud’s phenomenon (P = 0.009) were significantly more common in the anti-Ro52-positive patients. Anti-Ro52-positive IIP patients have clinical features consistent with IPAF. Anti-Ro52 may have an important role in detecting the autoimmune phenotype in IIP patients.

Forced Oscillation Measurements in Patients with Idiopathic Interstitial Pneumonia Subjected to Pulmonary Rehabilitation.

(1) Background: Pulmonary rehabilitation (PR) plays a significant therapeutic role for patients with idiopathic interstitial pneumonia (IIP). The study assessed the impact of physical activity on lung function measured by forced oscillation technique (FOT). (2) Methods: The study involved 48 patients with IIP subjected to a 3-week inpatient PR. The control group included IIP patients (n = 44) on a 3-week interval without PR. All patients were assessed at baseline and after 3 weeks of PR by FOT, spirometry, plethysmography, grip strength measurement and the 6-minute walk test. (3) Results: There were no significant changes in FOT measurements in the PR group, except for reduced reactance at 11 Hz, observed in both groups (p < 0.05). Patients who completed PR significantly improved their 6-min walk distance (6MWD) and forced vital capacity (FVC). The change in 6MWD was better in patients with higher baseline reactance (p = 0.045). (4) Conclusions: Patients with IIP benefit from PR by an increased FVC and 6MWD; however, no improvement in FOT values was noticed. Slow disease progression was observed in the study and control groups, as measured by reduced reactance at 11 Hz. Patients with lower baseline reactance limitations achieve better 6MWD improvement.

P16‐62: The prognostic factor of idiopathic interstitial pneumonias patients complicated with pneumothorax: A multicenter retrospective study

P16‐62: The prognostic factor of idiopathic interstitial pneumonias patients complicated with pneumothorax: A multicenter retrospective study

Clinical significance of anti-NOR90 antibodies in systemic sclerosis and idiopathic interstitial pneumonia.

Anti-NOR90 antibodies are usually found in patients with SSc; however, their clinical relevance remains obscure. We developed an ELISA for measuring them to investigate the clinical features of patients with anti-NOR90 antibodies. Serum samples from 1252 patients with various conditions from Nagoya University Hospital and 244 patients with idiopathic interstitial pneumonia (IIP) from Tosei General Hospital were included. Anti-NOR90 antibodies were assayed by an ELISA using the recombinant protein produced by in vitro transcription/translation. Five (0.4%) patients in the Nagoya University Hospital cohort had anti-NOR90 antibodies. One patient with diffuse cutaneous SSc, three with limited cutaneous SSc, and one with Raynaud's disease were positive for anti-NOR90 antibodies. Anti-NOR90 antibodies were found more frequently in patients with systemic scleroderma-spectrum disorders (SSDs) than without SSDs (5/316 vs 0/936, P <0.00101) and were found more frequently in patients with SSc than without SSc (4/249 vs 0/528, P <0.0104) in the systemic autoimmune rheumatic diseases cohort. Three of the four anti-NOR90-positive SSc patients had interstitial lung disease (ILD), and two of those four had cancer. Three (1.2%) patients in the Tosei General Hospital cohort had anti-NOR90 antibodies. All three of the anti-NOR90-positive IIP patients had gastrointestinal tract involvement, and two of those three had cancer or skin lesions observed in SSc. Although anti-NOR90 antibodies are rarely found in clinics, our ELISA is useful for their detection. Further studies are needed to confirm the association of anti-NOR90 antibodies with ILD and cancer in SSc and IIP patients.

Role of VEGF Polymorphisms in the Susceptibility and Severity of Interstitial Lung Disease.

The search for biomarkers that can help to establish an early diagnosis and prognosis of interstitial lung disease (ILD) is of potential interest. VEGF polymorphisms have been implicated in the development of several lung disorders. Consequently, we assessed, for the first time, the role of VEGF polymorphisms in the susceptibility and severity of ILD. A total of 436 Caucasian ILD patients (244 with idiopathic interstitial pneumonias (IIPs) and 192 with non-IIP) and 536 ethnically-matched healthy controls were genotyped for VEGF rs833061, rs1570360, rs2010963, rs3025020, and rs3025039 polymorphisms by TaqMan assays. Pulmonary function tests were collected from all the patients. VEGF serum levels were determined by ELISA in a subgroup of patients. No VEGF genotype, allele, carrier, or haplotype differences were found between ILD patients and controls as well as between IIP and non-IIP patients. However, an association of rs1570360 with IIP in women and also with lung function in IIP patients was found. None of the VEGF polymorphisms were associated with VEGF levels. In conclusion, our results suggest that VEGF does not seem to play a relevant role in ILD, although rs1570360 may influence the severity of ILD in women and a worse outcome in IIP patients.

Simple method for detecting idiopathic interstitial pneumonias by measuring vertical lung length on chest X-ray

Detection of idiopathic interstitial pneumonias (IIPs) on chest X-ray is difficult for non-specialist physicians, especially in patients with mild IIPs. The current study aimed to evaluate the usefulness of a simple method for detecting IIPs by measuring vertical lung length (VLL) in chest X-rays to quantify decreased lung volume. A total of 280 consecutive patients with IIPs were randomly allocated to exploratory and validation cohorts, and 140 controls were selected for each cohort by propensity score-matching. Upper (uVLL; from apex to tracheal carina), lower (lVLL; from carina to costophrenic angle), and total VLL (tVLL; from apex to costophrenic angle), and the l/uVLL ratio were measured on chest X-rays. Patients in the exploratory cohort had significantly decreased uVLL, lVLL, tVLL, and l/uVLL ratio compared with controls (all p < 0.001). Receiver operating characteristic curve analyses demonstrated that lVLL (area under the curve [AUC] 0.86, sensitivity 0.65, specificity 0.92), tVLL (AUC 0.83, sensitivity 0.75, specificity 0.80), and l/uVLL ratio (AUC 0.80, sensitivity 0.72, specificity 0.79) had high diagnostic accuracies for IIPs. These results were reproduced in the validation cohort. IIP patients thus have decreased VLLs, and measurements of VLL may thus aid the accurate detection of IIPs.

Long-term effects of home-based pulmonary rehabilitation on idiopathic interstitial pneumonia patients

Currently, interstitial lung disease (ILD) has no unified treatment plan. Home-based pulmonary rehabilitation (PR), as a non-pharmacological treatment, is a non-invasive and low-cost option for improving exercise capacity and quality of life. This study explores the impact of home-based PR on lung function, and the quality of life of patients with ILD. In this randomized prospective study, 60 patients with ILD were randomly assigned to the home-based PR intervention and traditional drug treatment groups, and they were followed for 12 months. The outcome measures were the 6-min walk distance (6MWD), exercise-related dyspnea, and St George’s Respiratory Questionnaire score (SGRQ). It found that the 6MWD results were significantly improved from 348.5 ± 106.1 m at baseline to 403.6 ± 100.3 m on the completion of PR and 443.8 ± 96.5 at 1-year follow-up (P = 0.001). Compared with the control group, the home-based PR group had slightly improved pulmonary function. Furthermore, the severity of dyspnea evaluated with mMRC in the home-based PR group improved from 2.9 ± 1.1 at baseline to 2.2 ± 0.9 after the home-based PR program, and this improvement persisted after 12 months (P = 0.001). Additionally, home-based PR for patients with ILD improved the functional pulmonary performance and the SGRQ score results.

Clinical significance of minor salivary gland biopsy in patients with idiopathic interstitial pneumonia

BackgroundSignificant overlap may occur between idiopathic interstitial pneumonia (IIP) and connective tissue diseases (CTDs) that do not meet the established classification criteria for any known CTDs (i.e., occult CTD). Performing minor salivary gland biopsy (MSGB) to detect occult primary Sjogren's syndrome (pSS) in IIP patients is not well studied. MethodsConsecutive IIP patients underwent MSGB to determine the prevalence of positive MSGB findings. Furthermore, we characterised the clinical, physiological and serological profiles of the MSGB-positive patients. Cox regression models were used to identify independent predictors of survival. ResultsThe data of 155 patients with IIP were available for analysis. Sixty patients (38.7%) had positive MSGB findings. Of them, the mean age was 63.3 years, 51.6% were women, usual interstitial pneumonia (UIP) was the predominant pattern (63.3%), and seronegative antibodies (61.6%) were likely. Patients with positive MSGB findings had significantly greater survival than those with negative MSGB findings (p = 0.041). After stratifying the MSGB cohort based on the presence of a UIP pattern, no significant difference in survival was noted between those with positive MSGB-UIP pattern and those with a negative MSGB-UIP pattern (p = 0.231). Multivariate analysis on all UIP patients showed that higher forced vital capacity (p = 0.010) and smoking status (p = 0.035) were independently associated with survival. ConclusionsA substantial number of IIP patients had underlying occult CTD, highlighting the importance of performing MSGB to identify the salivary component of pSS when evaluating patients with interstitial lung disease of undetermined aetiology.

Evaluation of health-related quality of life and the related factors in a group of Chinese patients with interstitial lung diseases

Interstitial lung diseases (ILDs) include a wide variety of chronic progressive pulmonary diseases characterized by lung inflammation, fibrosis and hypoxemia and can progress to respiratory failure and even death. ILDs are associated with varying degrees of quality of life impairments in affected people. Studies on the quality of life in patients with ILDs are still limited, and there are few studies with long-term follow-up periods in these patients. Data from patients who were clinically diagnosed with ILDs in the Respiratory Department, Beijing Chaoyang Hospital, Capital Medical University from January 2017 to February 2018 were collected. Clinical status and HRQoL were assessed at baseline and subsequently at 6- and 12-month intervals with the LCQ, mMRC, HADS, SF-36, and SGRQ. Multivariate linear regression was used to evaluate the determinants of the decline in HRQoL. A total of 139 patients with idiopathic interstitial pneumonia (IIP) and 30 with connective tissue disease-associated ILD (CTD-ILD) were enrolled, 140 of whom completed the follow-up. The mean age was 63.7 years, and 92 patients were men. At baseline, the decline in HRQoL assessed by the SF-36 and SGRQ was significantly associated with the mMRC, LCQ and HADS depression score. In the follow-up, changes in FVC%, DLco%, mMRC and LCQ were significantly associated with changes in HRQoL. HRQoL in both IIP and CTD-ILD patients deteriorates to varying degrees, and the trend suggests that poor HRQoL in these patients is associated with many determinants, primarily dyspnea, cough and depression. Improving HRQoL is the main aim when treating patients living with ILDs.

GPRC5A reduction contributes to pollutant benzo[a]pyrene injury via aggravating murine fibrosis, leading to poor prognosis of IIP patients

Air pollution exposure is recently reported to be one of the drivers of exacerbation in idiopathic pulmonary fibrosis (IPF). But there was a lack of direct evidence between pollution and lung fibrosis. Here, our data show effects of pollutant benzo[a]pyrene (BaP) and protein G-protein-coupled receptor family C group 5 type A (GPRC5A) on pulmonary fibrosis, which might help limit potential pollutant injury and disease progression.We cross-referenced epithelial differentially-expressed-genes (DEGs) from pollutant injury and published experimental fibrosis and IPF patients' data, top common-DEG (CO-DEG) GPRC5A was identified as a potential link between exposure-damage and fibrogenesis. The role of GPRC5A was evaluated under BaP exposure, in idiopathic interstitial pneumonia (IIP) tissue-array and via CRISPR/Cas9 knockout mice (Gprc5a−/−).BaP exposure enhanced bleomycin (BLM)-induced murine pulmonary fibrosis with increased Fibronectin and α-SMA expression in primary fibroblasts, thickened respiratory membrane and damaged alveolar type II cell, combined with Gprc5a decline in fibrotic mass. GPRC5A mRNA reduced after 10–14 days' BaP exposure in human epithelial cell A549. GPRC5A protein was further found to decrease in IIP epithelium, especially hyperplastic regions. A high epithelial GPRC5A expression score was positively associated with long survival time (R = 0.34) while negatively with high age (R = −0.4) and IIP type IPF (R = −0.5). Low GPRC5A expression predicts poor prognosis (HR = 4.5). Gprc5a depletion aggravated mortality rate (50%) with increased collagen deposition and myofibroblast activation under BLM treatment and exacerbated BaP injury in lung remodeling. Vitamin metabolic imbalance and Mitofusion2 (Mfn2) or Opa1-regulated mitochondrial dynamics were deduced to contribute to Gprc5a depletion and fibrogenesis.Pollutant BaP exposure worsens murine fibrosis and myofibroblast activation via GPRC5A reduction in the damaged epithelium. GPRC5A deficiency was first confirmed to contribute to both poor prognosis of IIP patients and fibrogenesis in murine model; thus, GPRC5A could serve as a novel therapeutic target in pollutant injury and pulmonary fibrosis.

Clinical significance of thyroid hormone and antibodies in patients with idiopathic interstitial pneumonia.

BackgroundHypothyroidism was recently reported to be common and to predict mortality in patients with idiopathic pulmonary fibrosis (IPF). In addition, a high prevalence of hypothyroidism was shown in patients with idiopathic pleuroparenchymal fibroelastosis. However, in idiopathic interstitial pneumonia (IIP), a clinical significance of thyroid function has not been clarified in detail. The goal of this study was to investigate the clinical significance of thyroid function and the presence of thyroid antibodies in IIP.MethodsWe have reviewed IIP patients, and analyzed the positivity of thyroid antibodies at first. Next, the relationship of clinical characteristics with thyroid function and the positivity of thyroid antibodies was analyzed. Lastly, the positivity of thyroid antibodies and other autoantibodies was evaluated.ResultsIn IIP patients, thyroglobulin and thyroid peroxidase antibodies were positive in 17 and 16%, respectively, and 22% of patients had either or both antibodies. Subclinical and/or overt hypothyroidism was confirmed in 7% of IIP patients. The free thyrotropin level had a significant positive correlation with vital capacity and a significant negative correlation with the C-reactive protein and surfactant protein-A levels, and erythrocyte sedimentation ratio (ESR). In addition, autoantibodies suggestive of connective tissue diseases (CTDs) were positive in more than two thirds of IIP patients with the thyroid antibody, and the positive rate of antinuclear and proteinase-3 anti-neutrophil cytoplasmic antibodies was significantly higher in IIP patients with thyroid antibodies than those without the antibodies.ConclusionsAlthough thyroid dysfunction is not frequent, thyroid hormones and thyroid antibodies are possibly involved in the pathogenesis of IIP and their evaluation may be clinically useful to identify the clinical phenotype of IIP with autoimmune features.