Eligibility Criteria:
Inclusion Criteria:
* Inclusion Criteria for Probable Idiopathic Pulmonary Fibrosis (IPF)
* Adult male or female patients aged 40 to 85 years
* Women of childbearing age should not be pregnant, planning to get pregnant or breast-feeding.
* Command of the English language to be able to give informed consent.
* Probable IPF requiring bronchoscopy to confirm the diagnosis, agreed within the local multi-disciplinary team (MDT).,according to the American Thoracic Society/European Respiratory Society/Japanese Respiratory Society/ American Latin Thoracic Association (ATS/ERS/JRS/ALAT) guidelines (2018) (3)
* IPF disease diagnosis within the past 5 years
* Usual Interstitial Pneumonia (UIP) on HRCT scan.
* Recent lung function criteria:
* Forced vital capacity (FVC) \>40% of predicted value.
* Carbon monoxide diffusing lung capacity (DLco) corrected for haemoglobin \>30% of predicted value
Inclusion criteria for Sarcoidosis
* Adult male or female patients aged 18 years and over
* Women of childbearing age should not be pregnant, planning to get pregnant or breast-feeding.
* Clinical symptoms, CT scan and biopsy diagnosis of sarcoidosis
* Patients with lung parenchymal disease and pulmonary stage II or more
* Recent lung function criteria
* FVC\>50% predicted
* DLCO \>40% predicted
Inclusion criteria for Healthy Volunteers
* Age between 40 to 85 years, age and sex to match the group with IPF
* Healthy subjects without any diseases that may cause inflammation
* Women of childbearing age should not be pregnant, planning to get pregnant or breast-feeding.
* Currently non-smokers: see exclusion criteria
Exclusion Criteria:Exclusion Criteria for probable IPF and Sarcoidosis Patients
Respiratory Conditions other than IPF or sarcoidosis:
* Confirmed diagnosis of occupational lung disease
* Drug-induced lung disease or hypersensitivity pneumonitis
* Lung and systemic autoimmune disease including connective tissue disease. Patients with an auto-immune profile considered diagnostic for a specific connective tissue disease will be excluded, even in the absence of systemic symptoms. Non-specific rises in auto antibodies e.g. rheumatoid factor; anti-nuclear antibody etc. will not be used to exclude individuals from the study.
* Asbestosis or other asbestos related disease (pleural plaques, mesothelioma, asbestos pleural effusions)
* Granulomatous lung disease.
* Pulmonary artery hypertension (PAH) requiring a specific treatment.
* Predominant chronic obstructive pulmonary disease (COPD) with forced expiratory volume in 1 second /forced vital capacity (FEV1/FVC) \<0.70.
* Patients with active tuberculosis or incompletely treated latent tuberculosis infection
* Lung cancer
* Upper respiratory tract infections in the past 6 weeks.
Systemic Conditions
* History of vasculitis, autoimmune or connective tissue disease
* Known human immunodeficiency virus (HIV) or chronic viral hepatitis
* Clinically significant diseases (other than IPF or sarcoidosis) that may alter respiratory biomarkers: including other respiratory, gastrointestinal, endocrine, haematological, cardiovascular, genitourinary, skin or neurological diseases.
* Recent or ongoing malignant diseases.
* Significant nasal anatomical defects preventing nasal sampling: including hypertrophy of turbinates, major septum deviation, nasal polyposis or recurrent sinusitis and nasal mucosal defects
Bronchoscopy Contraindications
Any contra-indication to bronchoscopy as set out in British Thoracic Society guidelines (34)
Smoking
A detailed smoking history will be taken from all participants: to include total pack years, smoking in the past year, and smoking in the past 2 weeks.
The history will include cigarettes, pipe smoking, cigars, vaping, and shisha. Any form of smoking is not permitted within 2 weeks of bronchoscopy.
5.4.2 Exclusion Criteria for Healthy Volunteers
* Current inflammatory/ immunological conditions. Any clinically significant diseases that may alter respiratory biomarkers: including respiratory, gastrointestinal, endocrine, haematological, cardiovascular, genitourinary, skin or neurological diseases.
* Recent or ongoing malignant diseases.
* Significant nasal anatomical defects preventing nasal sampling: including hypertrophy of turbinates, major septum deviation, nasal polyposis or recurrent sinusitis and nasal mucosal defects
* Upper respiratory tract infections in the past 6 weeks.
* Cigarette smoking:
no cigarettes in the last 2 weeks not more than 10 cigarettes in the past year \<10 year lifetime pack history of smoking
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