Images in Sarcoidosis: new section of our Journal.

.

Genetic and geographic influence on phenotypic variation in European sarcoidosis patients.

Introduction: Sarcoidosis is a highly variable disease in terms of organ involvement, type of onset and course. Associations of genetic polymorphisms with sarcoidosis phenotypes have been observed and suggest genetic signatures. Methods: After obtaining a positive vote of the competent ethics committee we genotyped 1909 patients of the deeply phenotyped Genetic-Phenotype Relationship in Sarcoidosis (GenPhenReSa) cohort of 31 European centers in 12 countries with 116 potentially disease-relevant single-nucleotide polymorphisms (SNPs). Using a meta-analysis, we investigated the association of relevant phenotypes (acute vs. sub-acute onset, phenotypes of organ involvement, specific organ involvements, and specific symptoms) with genetic markers. Subgroups were built on the basis of geographical, clinical and hospital provision considerations. Results: In the meta-analysis of the full cohort, there was no significant genetic association with any considered phenotype after correcting for multiple testing. In the largest sub-cohort (Serbia), we confirmed the known association of acute onset with TNF and reported a new association of acute onset an HLA polymorphism. Multi-locus models with sets of three SNPs in different genes showed strong associations with the acute onset phenotype in Serbia and Lublin (Poland) demonstrating potential region-specific genetic links with clinical features, including recently described phenotypes of organ involvement. Discussion: The observed associations between genetic variants and sarcoidosis phenotypes in subgroups suggest that gene-environment-interactions may influence the clinical phenotype. In addition, we show that two different sets of genetic variants are permissive for the same phenotype of acute disease only in two geographic subcohorts pointing to interactions of genetic signatures with different local environmental factors. Our results represent an important step towards understanding the genetic architecture of sarcoidosis.

Initial behaviors and attitudes towards the COVID-19 vaccine in sarcoidosis patients: results of a self-reporting questionnaire.

BACKGROUND: Individuals with self-declared sarcoidosis are at increased risk of COVID-19 related morbidity and mortality for which vaccination can be lifesaving. Despite this, vaccine hesitancy remains a large barrier to global acceptance of vaccination against COVID-19. We aimed to identify individuals with sarcoidosis who had and had not been vaccinated against COVID-19 vaccine to 1) establish a safety profile of COVID-19 vaccination in those with sarcoidosis and 2) to elucidate factors that contribute to COVID-19 vaccine hesitancy. METHODS: A questionnaire inquiring about COVID-19 vaccination status, vaccination side effects, and willingness for future vaccination was distributed from December 2020 to May 2021 to individuals with sarcoidosis living in the US and European countries. Details regarding sarcoidosis manifestations and treatment were solicited. Vaccine attitudes were classified as pro or anti-COVID-19 vaccination for subgroup analysis. RESULTS: At the time of questionnaire administration, 42% of respondents had already received a COVID-19 vaccination, most of whom either denied side effects or reported a local reaction only. Those off sarcoidosis therapy were more likely to report systemic side effects. Among subjects who had not yet received a COVID-19 vaccine, 27% of individuals reported they would not receive one once available. Reasons against vaccination were overwhelmingly related to the lack of confidence in vaccine safety and/or efficacy and less related to concerns associated with convenience or complacency. Black individuals, women, and younger adults were more likely to decline vaccination. CONCLUSIONS: Among individuals with sarcoidosis, COVID-19 vaccination is well-accepted and well-tolerated. Subjects on sarcoidosis therapy reported significantly less vaccination side effects, and thus the correlation between side effects, vaccine type, and vaccine efficacy requires further investigation. Strategies to improve vaccination should focus on improving knowledge and education regarding vaccine safety and efficacy, as well as targeting sources of misinformation, particularly in young, black, and female subpopulations.

Krebs von den Lungen-6 (KL-6) in cerebrospinal fluid from neurosarcoidosis patients.

BACKGROUND: Krebs von den Lungen-6 (KL-6) is a high molecular weight (MW) glycoprotein mainly secreted by type II pneumocytes because of lung damage or during regeneration. Neurosarcoidosis (NS), where sarcoid granulomas involve the nervous system, occurs in 5-20% of patients with sarcoidosis. No data is currently available on KL-6 in serum or CSF of NS patients. The present study compared KL-6 concentrations in serum and CSF of NS patients versus others with neurodegenerative (ND) or chronic inflammatory demyelinating (DM) diseases. MATERIALS AND METHODS: Nine NS patients (mean age 46.2 years, range 16-61 years, M/F 5/4), nine patients with a chronic neurodegenerative disease (mean age 53.1 years, range 37-65 years, M/F 5/4) and nine patients with a chronic demyelinating disease (mean age 46.3 years, range 18-65 years, M/F 5/4) were retrospectively enrolled. RESULTS: Measurable CSF concentrations of KL-6 were detected in 7/9 NS patients but in no ND or DM patients. No significant differences in CSF concentrations of ACE were observed between the three groups (p=0.0819). In NS patients, CSF concentrations of KL-6 were directly correlated with CSF albumin index (r=0.98; p<0.0001), albumin (r=0.979, p=0.0001), IgG (r=0.928, p=0.0009) and total protein concentrations (r=0.945, p=0.0004). DISCUSSION: KL-6 is a high MW protein, under physiological conditions it is unlikely to cross the blood-brain barrier. We found KL-6 in CSF from NS and not from ND and DM patients. The finding sustains the specificity of changes in KL-6 in this granulomatous disease, suggesting it as a candidate biomarker for recognition of NS.

Prognostic Significance of Obstructive Sleep Apnea in a Population of Subjects with Interstitial Lung Diseases.

INTRODUCTION: Obstructive sleep apnea (OSA) is often observed in subjects with interstitial lung disease (ILD). It may have a negative impact on the course of ILD, but its prognostic significance in relation to other known indicators of poor outcome is unclear. METHODS: After a detailed work-up, including overnight unattended type III polygraphy, all subjects newly diagnosed with ILDs referred to our clinics were followed-up for at least 1.5 years or until death or progression of disease [> 10% decline in forced vital capacity (FVC) below baseline]. We analyzed relationships between some prespecified variables of interest, including sleeping results, to establish parameters predictive of progressive course. RESULTS: Our population consisted of 46 subjects (mean age 59.6 years; males 61%); 23.9% and 41% had idiopathic pulmonary fibrosis and ILD associated with systemic diseases, respectively. Mean baseline forced vital capacity and diffusion capacity of carbon monoxide were 83% and 57% of predicted, respectively. Mean (± SE) Apnea-Hypopnea Index (AHI) was 17 (± 3) events/h. AHI in the ranges 5-14.9, 15-29.9, and ≥ 30 was recorded in 14 (31%), 6 (13%), and 9 (20%) subjects, respectively. Mean distance covered in the 6-MWG walk test (6MWT) was 302 (± 19) m and 26 subjects (57%) showed exertional oxyhemoglobin desaturation. The median follow-up was about 18 months. Multivariate logistic regression analysis showed that exertional desaturation (HR 8.2; 1.8-36.5 95% CI; p = 0.006) and AHI ≥ 30, namely the threshold of severe OSA (HR 7.5; 1.8-30.6; p = 0.005), were the only independent variables related to progressive disease course. CONCLUSION: We conclude that exertional desaturation and elevated AHI had independent negative prognostic significance in our ILD population.

Characterization of NKG2-A/-C, Kir and CD57 on NK Cells Stimulated with pp65 and IE-1 Antigens in Patients Awaiting Lung Transplant.

INTRODUCTION: Cytomegalovirus (CMV) is the leading opportunistic infection in lung transplant (LTx) recipients. CMV is associated with graft failure and decreased survival. Recently, new antiviral therapies have been proposed. The present study aimed to investigate NK and T cell subsets of patients awaiting LTx. We analyzed the cellular populations between reactive and non-reactive QuantiFERON (QF) CMV patients for the prediction of immunological response to infection. METHODS: Seventeen pre-LTx patients and 15 healthy controls (HC) have been enrolled. QF and IFN-γ ELISA assay detections were applied. NK cell subsets and T cell and proliferation assay were detected before and after stimulation with pp-65 and IE-1 CMV antigens after stratification as QF+ and QF-. Furthermore, we quantified the serum concentrations of NK- and T-related cytokines by bead-based multiplex analysis. RESULTS: CD56brCD16lowNKG2A+KIR+ resulted in the best discriminatory cellular subsets between pre-LTx and HC. Discrepancies emerged between serology and QF assay. Better proliferative capability emerged from patients who were QF+, in particular in CD8 and CD25-activated cells. CD56brCD16low, adaptive/memory-like NK and CD8Teff were highly increased only in QF+ patients. CONCLUSIONS: QF more than serology is useful in the detection of patients able to respond to viral infection. This study provides new insights in terms of immunological responses to CMV in pre-LTX patients, particularly in NK and T cells biology.

BAL Transcriptomes Characterize Idiopathic Pulmonary Fibrosis Endotypes With Prognostic Impact.

BACKGROUND: Given the plethora of pathophysiologic mechanisms described in idiopathic pulmonary fibrosis (IPF), we hypothesize that the mechanisms driving fibrosis in IPF may be different from one patient to another. RESEARCH QUESTION: Do IPF endotypes exist and are they associated with outcome? STUDY DESIGN AND METHODS: Using a publicly available gene expression dataset retrieved from BAL samples of patients with IPF and control participants (GSE70867), we clustered IPF samples based on a dimension reduction algorithm specifically designed for -omics data, called DDR Tree. After clustering, gene set enrichment analysis was performed for functional annotation, associations with clinical variables and prognosis were investigated, and differences in transcriptional regulation were determined using motif enrichment analysis. The findings were validated in three independent publicly available gene expression datasets retrieved from IPF blood samples. RESULTS: One hundred seventy-six IPF samples from three centers were clustered in six IPF clusters, with distinct functional enrichment. Although clinical characteristics did not differ between the clusters, one cluster conferred worse sex-age-physiology score-corrected survival, whereas another showed a numeric trend toward worse survival (P = .08). The first was enriched for increased epithelial and innate and adaptive immunity signatures, whereas the other showed important telomere and mitochondrial dysfunction, loss of proteostasis, and increased myofibroblast signatures. The existence of these two endotypes, including the impact on survival of the immune endotype, was validated in three independent validation cohorts. Finally, we identified transcription factors regulating the expression of endotype-specific survival-associated genes. INTERPRETATION: Gene expression-based endotyping in IPF is feasible and can inform clinical evolution. As endotype-specific pathways and survival-associated transcription factors are identified, endotyping may open up the possibility of endotype-tailored therapy.

Lung cancer and interstitial lung diseases: the lack of prognostic impact of lung cancer in IPF.

Lung Cancer (LC) is the first cause of death worldwide. Recently increased interest in interstitial lung diseases (ILD) has highlighted an association with lung cancer, offering interesting insights into the pathogenesis of the latter. Describe the association between lung cancer and ILD and evaluate the impact of LC on survival in these populations. We collected clinical, radiological, histologic data of 53 cases of advanced pulmonary fibrosis with lung cancer: 17 with UIP pattern (usual interstitial pneumonia, UIP/IPF-LC) and 36 with non-UIP pattern (ILD-LC). Adenocarcinoma was the most frequent histological subtype of lung cancer in all three groups and in UIP/IPF-LC developed in the lung periphery and in an advanced fibrosis context. Patients with DLCO% < 38% showed survival < 10 months, irrespective of group and development of carcinoma in UIP/IPF does not necessarily affect survival, unlike in SR-ILD. Our results confirm that the oncogenic mechanism is closely linked to fibrotic and inflammatory processes and that the development of carcinoma affects survival in SR-ILD but not in IPF.

Renal involvement in sarcoidosis: histological patterns and prognosis, an Italian survey.

BACKGROUND: Granulomatous interstitial nephritis in sarcoidosis (sGIN) is generally clinically silent, but in <1% causes acute kidney injury (AKI). METHODS: This Italian multicentric retrospective study included 39 sarcoidosis-patients with renal involvement at renal biopsy: 31 sGIN-AKI, 5 with other patterns (No-sGIN-AKI), 3 with nephrotic proteinuria. We investigate the predictive value of clinical features, laboratory, radiological parameters and histological patterns regarding steroid response. Primary endpoint: incident chronic kidney disease (CKD) beyond the 1°follow-up (FU) year; secondary endpoint: response at 1°line steroid therapy; combined endpoint: the association of initial steroid response and outcome at the end of FU. RESULTS: Complete recovery in all 5 No-sGIN-AKI-patients, only in 45% (13/29) sGIN-AKI-patients (p=0.046) (one lost in follow-up, for another not available renal function after steroids). Nobody had not response. Primary endpoint of 22 sGIN-AKI subjects: 65% (13/20) starting with normal renal function developed CKD (2/22 had basal CKD; median FU 77 months, 15-300). Combined endpoint: 29% (6/21) had complete recovery and final normal renal function (one with renal relapse), 48% (10/21) had partial recovery and final CKD (3 with renal relapse, of whom one with basal CKD) (p=0.024). Acute onset and hypercalcaemia were associated to milder AKI and better recovery than subacute onset and patients without hypercalcaemia, women had better endpoints than men. Giant cells, severe interstitial infiltrate and interstitial fibrosis seemed negative predictors in terms of endpoints. CONCLUSIONS: sGIN-AKI-patients with no complete recovery at 1°line steroid should be treated with other immunosuppressive to avoid CKD, in particular if males with subacute onset and III stage-not hypercalcaemic AKI.

Harnessing the Role of HDAC6 in Idiopathic Pulmonary Fibrosis: Design, Synthesis, Structural Analysis, and Biological Evaluation of Potent Inhibitors.

Idiopathic pulmonary fibrosis (IPF) is an interstitial lung disease characterized by a progressive-fibrosing phenotype. IPF has been associated with aberrant HDAC activities confirmed by our immunohistochemistry studies on HDAC6 overexpression in IPF lung tissues. We herein developed a series of novel hHDAC6 inhibitors, having low inhibitory potency over hHDAC1 and hHDAC8, as potential pharmacological tools for IPF treatment. Their inhibitory potency was combined with low in vitro and in vivo toxicity. Structural analysis of 6h and structure-activity relationship studies contributed to the optimization of the binding mode of the new molecules. The best-performing analogues were tested for their efficacy in inhibiting fibrotic sphere formation and cell viability, proving their capability in reverting the IPF phenotype. The efficacy of analogue 6h was also determined in a validated human lung model of TGF-ß1-dependent fibrogenesis. The results highlighted in this manuscript may pave the way for the identification of first-in-class molecules for the treatment of IPF.

ERS clinical practice guidelines on treatment of sarcoidosis.

BACKGROUND: The major reasons to treat sarcoidosis are to lower the morbidity and mortality risk or to improve quality of life (QoL). The indication for treatment varies depending on which manifestation is the cause of symptoms: lungs, heart, brain, skin or other manifestations. While glucocorticoids remain the first choice for initial treatment of symptomatic disease, prolonged use is associated with significant toxicity. Glucocorticoid-sparing alternatives are available. The presented treatment guidelines aim to provide guidance to physicians treating the very heterogenous sarcoidosis manifestations. METHODS: A European Respiratory Society Task Force committee composed of clinicians, methodologists and patients with experience in sarcoidosis developed recommendations based on the GRADE (Grading of Recommendations, Assessment, Development and Evaluations) methodology. The committee developed eight PICO (Patients, Intervention, Comparison, Outcomes) questions and these were used to make specific evidence-based recommendations. RESULTS: The Task Force committee delivered 12 recommendations for seven PICOs. These included treatment of pulmonary, cutaneous, cardiac and neurologic disease as well as fatigue. One PICO question regarding small-fibre neuropathy had insufficient evidence to support a recommendation. In addition to the recommendations, the committee provided information on how they use alternative treatments, when there was insufficient evidence to support a recommendation. CONCLUSIONS: There are many treatments available to treat sarcoidosis. Given the diverse nature of the disease, treatment decisions require an assessment of organ involvement, risk for significant morbidity, and impact on QoL of the disease and treatment.

The Role of Galectins in Chronic Lung Allograft Dysfunction.

BACKGROUND: Galectins are proteins that bind ß-galactosides such as N-acetyllactosamine present in N-linked and O-linked glycoproteins and that seem to be implicated in inflammatory and immune responses as well as fibrotic mechanisms. This preliminary study investigated serum galectins as clinical biomarkers in lung transplant patients with chronic lung allograft dysfunction (CLAD), phenotype bronchiolitis obliterans syndrome (BOS). MATERIALS AND METHODS: Nineteen lung transplant patients [median age (IQR), 55 (45-62) years; 53% males] were enrolled in the study. Peripheral blood concentrations of galectins-1, 3 and 9 were determined with commercial ELISA kits. RESULTS: Galectin-1 concentrations were higher in BOS than in stable LTX patients (p = 0.0394). In logistic regression analysis, testing BOS group as dependent variable with Gal-1 and 3 as independent variables, area under the receiver operating characteristics (AUROC) curve was 98.9% (NPV 90% and PPV 88.9%, p = 0.0003). With the stable LTX group as dependent variable and Gal-1, 3 and 9 as independent variables, AUROC was 92.6% (NPV 100% and PPV 90%, p = 0.0023). In stable patients were observed an inverse correlation of Gal-3 with DLCO% and KCO%, and between Gal-9 and KCO%. CONCLUSION: Galectins-1, 3 and 9 are possible clinical biomarkers in lung transplant patients with diagnostic and prognostic meaning. These molecules may be directly implicated in the pathological mechanisms of BOS. The hypothesis that they could be new therapeutic targets in BOS patients is intriguing and also worth exploring.

Regulatory and Effector Cell Disequilibrium in Patients with Acute Cellular Rejection and Chronic Lung Allograft Dysfunction after Lung Transplantation: Comparison of Peripheral and Alveolar Distribution.

BACKGROUND: The immune mechanisms occurring during acute rejection (AR) and chronic lung allograft dysfunction are a challenge for research and the balance between effector and regulatory cells has not been defined completely. In this study, we aimed to elucidate the interaction of effector cells, mainly Th17, Th1 and Th2, and regulatory cells including (CD4+CD25+CD127low/-) T reg cells and phenotypes of B regs, CD19+CD24hiCD38hi, CD19+CD24hiCD27hi and CD19+CD5+CD1d+. METHODS: Bronchoalveolar lavage cells (BAL) and peripheral blood mononuclear cells (PBMCs) from stable lung transplanted (LTx )subjects (n = 4), AR patients (n = 6) and bronchiolitis obliterans syndrome (BOS) (n = 6) were collected at the same time. Cellular subsets were detected through flow cytometry. RESULTS: A predominance of Th17 cells subtypes in the PBMCs and BAL and a depletion of Tregs, that resulted in decrease Treg/Th17 ratio, was observed in the AR group. CD19+CD24hiCD38hi Bregs resulted increased in BAL of AR patients. Th1 cells predominance and a reduction of Tregs cells was observed in BAL from AR patients. Moreover, multivariate analysis showed interdependences within studied variables revealing that effector cells and regulatory cells can effectively discriminate patients' immunological status. CONCLUSIONS: In AR, BOS and stable lung transplant, regulatory and effector cells clearly demonstrated different pathways of activation. Understanding of the balance of T cells and T and B regulatory cells can offers insights into rejection.

The role of the combination of echo-HRCT score as a tool to evaluate the presence of pulmonary hypertension in idiopathic pulmonary fibrosis.

Pulmonary hypertension (PH) is defined as an elevated mean pulmonary artery pressure at rest (mPAP ≥ 25 mmHg), evaluated by right heart catheterization (RHC). The aim of the present study was to evaluate HRCT findings in relation to transthoracic echocardiographic data to better characterize PH in IPF patients and to identify a non-invasive composite index with high predictive value for PH in these patients. 37 IPF patients were enrolled in this retrospective study. All patients underwent a complete assessment for PH, including transthoracic Doppler echocardiography, HRCT scan and right heart catheterization. Right heart catheterization was done in 19 patients (51.3%) as pre-lung transplant assessment and in 18 patients (48.6%) to confirm PH, suspected on the basis of echocardiography. Twenty out of 37 patients (54%) were confirmed to have PH by RHC. Multivariate regression showed that the combination of sPAP, PA area measured by HRCT and the ratio of the diameter of the segmental artery to that of the adjacent bronchus in the apicoposterior segment of the left upper lobe was strongly correlated with mPAP (R2 = 0.53; p = 0.0009). The ROC analysis showed that 931.6 was the ULN for PA area, with 86% sensitivity and 61% specificity (0.839 AUC); 20.34 was the ULN for the ratio of PA area to ascending aorta diameter, with 100% sensitivity and 50% specificity (0.804 AUC). The composite index proposed in the present study could help early detection of IPF patients suspected of PH requiring confirmation by RHC (if deemed clinically necessary).

Long-Term Follow-Up of Patients With Idiopathic Pulmonary Fibrosis Treated With Pirfenidone or Nintedanib: A Real-Life Comparison Study.

BACKGROUND: Pirfenidone and nintedanib are the sole pharmacological therapies currently approved for idiopathic pulmonary fibrosis (IPF). Limited comparison data is available in literature, despite they are both prescribed for mild-to-moderate disease. Here, we describe our almost 10 years real-life experience with antifibrotic treatment to investigate potential differences in terms of efficacy. POPULATION AND METHODS: We retrospectively recruited patients diagnosed with IPF and treated with pirfenidone or nintedanib at Siena Referral Center. Clinical, functional, safety and radiological data was collected at baseline and during the follow-up, according to our Center protocol. RESULTS: We retrospectively recruited 263 IPF patients (139 treated with pirfenidone and 124 with nintedanib) in the study. After 885.3 ± 559.5 days of observation, the median survival was 1224 days. No significant differences were found between pirfenidone and nintedanib in terms of survival and time to decline of forced vital capacity >10% (p = 0.8786 and p = 0.1677, respectively). A smaller lung diffusion for carbon monoxide (DL CO ) decrease was found after 1 year of therapy with nintedanib in respect to pirfenidone (p = 0.0167). Overall, 21 patients permanently discontinued antifibrotic treatment due to side effects (14 with pirfenidone, 7 with nintedanib); no fatal adverse events were recorded. DISCUSSION: Our results showed a similar effectiveness between pirfenidone and nintedanib in terms of mortality and functional disease progression. Both drugs confirmed their good tolerability profile and no new safety alerts were observed. Nintedanib was associated with a smaller reduction of DL CO after 1 year of follow-up compared with pirfenidone, maybe due to its antiangiogenic properties.

Serum Amyloid A in lung transplantation.

BACKGROUND: Serum Amyloid A (SAA) is an acute phase protein and we analyzed its concentrations in lung transplantated patients (LTX). METHODS: 26 LTX patients (58.6 ± 11 years) and 11 healthy controls (55 ± 11.3 years). Three groups of LTX patients: acute rejection (AR, 7) bronchiolitis obliterans syndrome (BOS, 3), acute infection (INF, 9) and stable patients (NEG, 7). RESULTS: In LTX patients SAA concentrations were significantly increased, particularly in AR and INF. In LTX-AR patients were observed a correlation between SAA levels and peripheral CD4+ lymphocyte percentage (r=0.9, p<0.01) and a reverse correlation with FVC percentages (r -0.94, p=0.01). CONCLUSIONS: SAA may represent a potential biomarker of LTX acute complications, with a prognostic value in AR. (Sarcoidosis Vasc Diffuse Lung Dis 2020; 37 (1): 2-7).

Lung transplant in patients with familial pulmonary fibrosis. / Transplante pulmonar em pacientes com fibrose pulmonar familiar.

Objective Familial pulmonary fibrosis (FPF) is defined as an idiopathic interstitial lung disease affecting two or more members of the same family; poor outcome with high risk of death and chronic lung allograft dysfunction (CLAD) after lung transplant has been reported in these patients. The present study aimed to compare the short- and long-term outcome of lung transplants in patients with FPF and patients transplanted because of other interstitial lung diseases. Method Clinical pre- and post-transplant data from 83 consecutive patients with pulmonary fibrosis who underwent lung transplant at our centre were collected retrospectively. Patients were divided into those with familial (n=9 FPF group) and those with non-familial pulmonary fibrosis (n=74 controls). Results The FPF group was composed of 4 females and 5 males; 44.5% were ex-smokers. The majority presented their CT scan and pathology evidence of usual interstitial pneumonia. Patients with FPF had significantly lower pre-transplant levels of haemoglobin and haematocrit. No other differences in pre- and post-transplant characteristics were observed concerning controls. The clinical post-operative course was similar in the two groups. No significant difference in one-year CLAD-free survival and overall survival was observed. Conclusion The post-transplant course of patients with FPF was similar to patients with non-familial pulmonary fibrosis, although more patients with FPF had pre-transplant anaemia. Short- and long-term outcome was comparable in both groups. Lung transplant proved to be a valid option for patients with FPF as it was for patients with other types of pulmonary fibrosis.

Idiopathic Pulmonary Fibrosis Serum proteomic analysis before and after nintedanib therapy.

Idiopathic pulmonary fibrosis (IPF) is a fatal progressive disease with a median survival of 2-5 years. Nintedanib is a small tyrosine kinase inhibitor that reduces IPF progression, significantly slowing the annual decline in Forced Vital Capacity (FVC). Very little data is available on the molecular mechanisms of this treatment in IPF, despite a growing interest in the definition of IPF pathogenesis and target therapy. A functional proteomic approach was applied to the analysis of serum samples from IPF patients in order to highlight differential proteins potentially indicative of drug-induced molecular pathways modifications and response to therapy. Twelve serum samples were collected from six IPF patients in care at Siena Regional Referral Center for Interstitial Lung Diseases (ILDs) and treated with nintedanib for one year. Serum samples were analyzed at baseline (T0 before starting therapy) and after one year of treatment (T1) and underwent differential proteomic and bioinformatic analysis. Proteomic analysis revealed 13 protein species that were significantly increased after one year of treatment. When the targets of nintedanib (VEGFR, FGFR and PDGFR) were added, enrichment analysis extracted molecular pathways and process networks involved in cell differentiation (haptoglobin and albumin), coagulation (antithrombin III), epithelial mesenchymal transition, cell proliferation and transmigration. PI3K and MAPK induced up-regulation of apolipoprotein C3. Proteomic study found 13 protein species up-regulated in IPF patients after one year of nintedanib treatment. Haptoglobin, a central hub of our analysis was validated by 2D-WB and ELISA as theranostic marker in a more numerous populations of patients.