Effect of age on human ACE2 and ACE2-expressing alveolar type II cells levels.

BACKGROUND: Angiotensin-converting enzyme 2 (ACE2) is the receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which causes COVID-19. Viral entry requires ACE2 and transmembrane protease serine 2 (TMPRSS2). Transcriptomic studies showed that children display lower ACE2 than adults, though gene expression levels do not always correlate with protein levels. We investigated the effect of age on ACE2 and TMPRSS2 protein expression in alveolar type II (AT2) cells in the lungs of children compared to adults. We also analysed the ratio of Ang-(1-7) to Ang II as a surrogate marker of ACE2 activity in the subjects' lung parenchyma. METHODS: Ang II and Ang-(1-7) levels and ACE2 and TMPRSS2 protein expression were measured by radioimmunoassay and immunohistochemistry, respectively. RESULTS: The amount of ACE2-expressing AT2 cells and ACE2 protein content were lower in children than in adults. Ang II levels were higher in children compared to adults and inversely correlated with the amount of ACE2-expressing AT2 cells. Children presented lower Ang-(1-7)/Ang II ratio than adult suggesting lower ACE2 activity in children. TMPRSS2 protein expression was not influenced by age. CONCLUSIONS: These results expand on previous transcriptomic studies and may partially explain the low susceptibility of children to SARS-CoV-2 infection. CATEGORY OF STUDY: Clinical original research IMPACT: Children display lower ACE2 protein content and activity compared to adults. Ang II levels were higher in children compared to adults and inversely correlated with the amount of ACE2-expressing AT2 cells TMPRSS2 protein expression was not influenced by age. These results expand on previous transcriptomic studies and may partially explain the low susceptibility of children to SARS-CoV-2 infection.

Histopathology of the idiopathic interstitial pneumonias (IIP): A review.

The 2013 American Thoracic Society/European Respiratory Society consensus classification update of the idiopathic interstitial pneumonias (IIP) included several important modifications to the organization and spectrum of the diseases that were proposed in an earlier multidisciplinary consensus document in 2002. The histopathology of the now 'major' and 'rare' IIP is presented here with exposition of the newly included entity of a distinctive upper lobe fibrotic lung disease referred to as idiopathic pleuroparenchymal fibroelastosis. The 'rare histological patterns' of acute fibrinous and organizing pneumonia and bronchiolocentric patterns of interstitial pneumonia are illustrated and discussed.

Home monitoring in interstitial lung diseases.

The widespread use of smartphones and the internet has enabled self-monitoring and more hybrid-care models. The COVID-19 pandemic has further accelerated remote monitoring, including in the heterogenous and often vulnerable group of patients with interstitial lung diseases (ILDs). Home monitoring in ILD has the potential to improve access to specialist care, reduce the burden on health-care systems, improve quality of life for patients, identify acute and chronic disease worsening, guide treatment decisions, and simplify clinical trials. Home spirometry has been used in ILD for several years and studies with other devices (such as pulse oximeters, activity trackers, and cough monitors) have emerged. At the same time, challenges have surfaced, including technical, analytical, and implementational issues. In this Series paper, we provide an overview of experiences with home monitoring in ILD, address the challenges and limitations for both care and research, and provide future perspectives. VIDEO ABSTRACT.

Renin-angiotensin system blockade on angiotensin-converting enzyme 2 and TMPRSS2 in human type II pneumocytes.

AIMS: Angiotensin-converting enzyme (ACE) 2 is the receptor for severe acute respiratory syndrome coronavirus 2 which causes coronavirus disease 2019 (COVID-19). Viral cellular entry requires ACE2 and transmembrane protease serine 2 (TMPRSS2). ACE inhibitors (ACEIs) or angiotensin (Ang) receptor blockers (ARBs) influence ACE2 in animals, though evidence in human lungs is lacking. We investigated ACE2 and TMPRSS2 in type II pneumocytes, the key cells that maintain lung homeostasis, in lung parenchymal of ACEI/ARB-treated subjects compared to untreated control subjects. MAIN METHODS: Ang II and Ang-(1-7) levels and ACE2 and TMPRSS2 protein expression were measured by radioimmunoassay and immunohistochemistry, respectively. KEY FINDINGS: We found that the ratio Ang-(1-7)/Ang II, a surrogate marker of ACE2 activity, as well as the amount of ACE2-expressing type II pneumocytes were not different between ACEI/ARB-treated and untreated subjects. ACE2 protein content correlated positively with smoking habit and age. The percentage of TMPRSS2-expressing type II pneumocytes was higher in males than females and in subjects under 60 years of age but it was not different between ACEI/ARB-treated and untreated subjects. However, there was a positive association of TMPRSS2 protein content with age and smoking in ACEI/ARB-treated subjects, with high TMPRSS2 protein levels most evident in ACEI/ARB-treated older adults and smokers. SIGNIFICANCE: ACEI/ARB treatment influences human lung TMPRSS2 but not ACE2 protein content and this effect is dependent on age and smoking habit. This finding may help explain the increased susceptibility to COVID-19 seen in smokers and older patients with treated cardiovascular-related pathologies.

Experiencia en la Argentina del Programa de uso compasivo con nintedanib en el tratamiento de la Fibrosis Pulmonar Idiopática / Experience with the Compassionate Use Program of nintedanib for the treatment of Idiopathic Pulmonary Fibrosis in Argentina

Introducción: La Fibrosis Pulmonar Idiopática (FPI) es una enfermedad pulmonar difusa (EPD) de etiología desconocida, crónica y progresiva. Ocurre en adultos mayores, se encuentra limitada a los pulmones y se asocia con la patente anatomopatológica y/o tomográfica de neumonía intersticial usual (NIU). El curso de la enfermedad es progresivo y se asocia con una supervivencia media a 5 años del 20%. Objetivos: Conocer las características clínicas y de función pulmonar del grupo de pacientes con FPI ingresados al programa de uso compasivo (NPU); conocer el perfil de seguridad reportado con nintedanib. Materiales y Métodos: Estudio retrospectivo descriptivo transversal en donde se incluyeron 54 pacientes ingresados al programa de NPU desde el 1 de septiembre de 2015 hasta el 10 de agosto de 2016. Los datos se recolectaron de los registros del programa de NPU. Resultados: Cincuenta y cuatro pacientes con FPI fueron incluidos en el programa de NPU, de ellos 47 recibieron nintedanib y se analizaron los datos del total de estos últimos. Treinta y siete (78.72%) eran varones, la edad media al inicio del tratamiento era 67.47 ± 7.85 años y en 9 casos (19.14%) el diagnóstico se estableció mediante biopsia pulmonar. La capacidad vital forzada (CVF) media al inicio del tratamiento era de 65.87 ± 19.23 expresada en porcentaje del valor predictivo; la capacidad de difusión de dióxido de carbono media (DLCO) expresada en porcentaje del valor predictivo era de 38.74 ± 3.09. El tiempo de evolución desde el diagnóstico de FPI hasta el inicio del tratamiento con nintedanib era de 27.17± 27.9 meses (mediana 17). La exposición de la droga promedio hasta el corte era de 9.92 semanas ± 2.15 (mediana: 10 semanas). En 7 casos (31.91%) la CVF era mayor del 80%, en 22 (46.80%) casos entre 50 y 79% y en 10 casos (21.27%) era menor de 49%. En total 7 pacientes (14.89%) presentaron eventos adversos: 5 (10.6%) pacientes presentaron descenso ponderal, 4 (8.51%) diarrea, 2 pacientes presentaron náusea, 1 (2.12%) elevación de las enzimas hepáticas y 1 (2.12%) prurito. En la mayoría de los casos los eventos adversos aparecieron durante las 2 primeras semanas del inicio del tratamiento con nintedanib. En 3 (6.38%) casos fue mandatorio la suspensión del nintedanib definitivamente por eventos adversos y en 4 (8.51%) se debió titular la dosis a 100 mg cada 12 horas. Del total, 6 (12.76%) pacientes fallecieron por progresión de su enfermedad de base. Conclusiones: Al igual que lo reportado por otros grupos, el nintedanib presenta un perfil de seguridad manejable y tolerable. En nuestra serie de 47 pacientes con FPI que recibieron al menos una dosis de nintedanib, el 14.89% presentó algún evento adverso que solo en 3 pacientes (6.38%) motivó la suspensión definitiva del fármaco.

Experience with the Compassionate Use Program of nintedanib for the treatment of Idiopathic Pulmonary Fibrosis in Argentina

Introduction: Idiopathic Pulmonary Fibrosis (IPF) is a diffuse lung disease (DLD) of unknown etiology that is chronic and progressive. It occurs in older adults; it is restricted to the lungs and it is associated with the anatomopathological and/or tomographic pattern of Usual Interstitial Pneumonia (UIP). The evolution of the disease is progressive and it is associated with a mean 5-year survival rate of 20%. Objectives: to identify the clinical and pulmonary function characteristics in the group of patients with IPF included in the Compassionate Use Program (NPU, Named Patient Use); to identify the safety profile reported with nintedanib. Materials and methods: a retrospective, descriptive and cross-sectional study including 54 patients enrolled in the NPU program from September 1st, 2015 to August 10th, 2016. Data were collected from the NPU program records. Results: fifty-four patients with IPF were included in the NPU program, of whom 47 received nintedanib; the data from the latter were analyzed. Thirty-seven (78.72%) were males, with a mean age at the beginning of treatment of 67.47 ± 7.85 years, and in 9 cases (19.14%) the diagnosis was confirmed by lung biopsy. The mean forced vital capacity (FVC) at the beginning of treatment was 65.87±19.23 and it is presented as the percentage of the predictive value; the mean carbon dioxide diffusing capacity (DLCO) presented as the percentage of the predictive value was 38.74 ± 3.09. The time of progression from the diagnosis of IPF to the beginning of the treatment with nintedanib was 27.17± 27.9 months (median 17). Average drug exposure to cut-off point was 9.92 weeks ± 2.15 (median: 10 weeks). In 7 cases (31.91%) the FVC was over 80%, in 22 (46.80%) cases it was between 50 and 79% and in 10 cases (21.27%) it was below 49%. In total, 7 patients (14.89%) exhibited adverse events: Five (10.6%) patients exhibited weight loss, 4 (8.51%) diarrhea, 2 patients had nausea, 1 (2.12%) an increase of the liver enzymes and 1 (2.12%) pruritus. In most cases, the adverse events appeared during the first 2 weeks after beginning the treatment with nintedanib. In 3 (6.38%) cases it was imperative to suspend nintedanib permanently due to the adverse effects and in 4 (8.51%) cases the dose had to be titrated to 100 mg every 12 hours. Out of the total of patients, 6 (12.76%) passed away due to the progression of their underlying disease. Conclusions: such as it was reported by other groups, nintedanib has a manageable and tolerable safety profile. In our series of 47 patients with IPF who received at least one dose of nintedanib, 14.89% had an adverse event that led to the permanent discontinuation of the drug in only 3 patients (6.38%).