Prolonged treatment with open-label pirfenidone in Hermansky-Pudlak syndrome pulmonary fibrosis

Anandamide is an Early Blood Biomarker of Hermansky-Pudlak Syndrome Pulmonary Fibrosis

Hermansky-Pudlak syndrome (HPS) is a group of rare genetic disorders, with several subtypes leading to fatal adult-onset pulmonary fibrosis (PF) and no effective treatment. Circulating biomarkers detecting early PF have not been identified. We investigated whether endocannabinoids could serve as blood biomarkers of PF in HPS. We measured endocannabinoids in the serum of HPS, IPF, and healthy human subjects and in a mouse model of HPSPF. Pulmonary function tests (PFT) were correlated with endocannabinoid measurements. In a pale ear mouse model of bleomycin-induced HPSPF, serum endocannabinoid levels were measured with and without treatment with zevaquenabant (MRI-1867), a peripheral CB1R and iNOS antagonist. In three separate cohorts, circulating anandamide levels were increased in HPS-1 patients with or without PF, compared to healthy volunteers. This increase was not observed in IPF patients or in HPS-3 patients, who do not have PF. Circulating anandamide (AEA) levels were negatively correlated with PFT. Furthermore, a longitudinal study over the course of 5-14 years with HPS-1 patients indicated that circulating AEA levels begin to increase with the fibrotic lung process even at the subclinical stages of HPSPF. In pale ear mice with bleomycin-induced HpsPF, serum AEA levels were significantly increased in the earliest stages of PF and remained elevated at a later fibrotic stage. Zevaquenabant treatment reduced the increased AEA levels and attenuated progression in bleomycin-induced HpsPF. Circulating AEA may be a prognostic blood biomarker for PF in HPS-1 patients. Further studies are indicated to evaluate endocannabinoids as potential surrogate biomarkers in progressive fibrotic lung diseases.

The protective effects of pirfenidone in preventing abdominal aortic aneurysm formation

Vascular endothelial growth factor (VEGF)-mediated angiogenesis participates in the initiation and progression of abdominal aortic aneurysm (AAA). Pirfenidone is a compound that has anti-inflammatory and antioxidant properties and suppresses angiogenesis. Pirfenidone targets the extracellular matrix (ECM) and has therapeutic effects on fibrotic diseases. Therefore, we speculated that pirfenidone might have meaningful therapeutic effects in AAA, and the current study was designed to investigate this capacity. An AAA model was constructed in mice using a long-term injection of angiotensin II (Ang II), followed by a 28-day administration of 200 mg/kg/day pirfenidone. Increased maximal external diameter of the abdominal artery, promoted levels of VEGF-A and its receptor VEGF-R2, upregulated matrix metallopeptidases (MMP)-2 and MMP-9, and elevated release of pro-inflammatory cytokines were observed in AAA mice, which were extremely repressed by 200 mg/kg pirfenidone. Human aortic endothelial cells (HAECs) were stimulated with Ang II for 1 day, in the presence or absence of pirfenidone (100 nM). Elevated expression of VEGF-A and VEGF-R2, facilitated proliferation, increased tube formation ability, and upregulated MMP-2 and MMP-9 were observed in Ang II-stimulated HAECs, all of which were significantly rescued by 100 nM pirfenidone. Finally, the elevated levels of myeloid differentiation primary response 88 and phosphorylated nuclear factor-kappa-B subunit p65 observed in Ang II-stimulated HAECs were repressed by pirfenidone. Collectively, pirfenidone alleviated AAA by inhibiting ECM degradation and ameliorating endothelial dysfunction.

Pulmonary function and structure abnormalities in children and young adults with osteogenesis imperfecta point to intrinsic and extrinsic lung abnormalities

PURPOSE

Pulmonary disease is the major cause of morbidity and mortality in osteogenesis imperfecta (OI). We investigated the contribution of intrinsic lung factors to impaired pulmonary function in children and young adults with OI types III, IV, VI.

METHODS

Patients with type III (n=8), IV (n=21), VI (n=5), VII (n=2) or XIV (n=1) OI (mean age 23.6 years) prospectively underwent pulmonary function tests (PFTs) and thoracic CT and radiographs.

RESULTS

PFT results were similar using arm span or ulnar length as height surrogates. PFTs were significantly lower in type III than type IV or VI OI. All patients with type III and half of type IV OI had lung restriction; 90% of patients with OI had reduced gas exchange. Patients with COL1A1 variants had significantly lower forced expiratory flow (FEF)25%-75% compared with those with COL1A2 variants. PFTs correlated negatively with Cobb angle or age. CT scans revealed small airways bronchial thickening (100%, 86%, 100%), atelectasis (88%, 43%, 40%), reticulations (50%, 29%, 20%), ground glass opacities (75%, 5%, 0%), pleural thickening (63%, 48%, 20%) or emphysema (13%, 19%, 20%) in type III, IV or VI OI, respectively.

CONCLUSION

Both lung intrinsic and extrinsic skeletal abnormalities contribute to OI pulmonary dysfunction. Most young adult patients have restrictive disease and abnormal gas exchange; impairment is greater in type III than type IV OI. Decreased FEF25%-75% and thickening of small bronchi walls indicate a critical role for small airways. Lung parenchymal abnormalities (atelectasis, reticulations) and pleural thickening were also detected. Clinical interventions to mitigate these impairments are warranted.

TRIAL REGISTRATION NUMBER

NCT03575221.

The world of rare interstitial lung diseases

The world of rare interstitial lung diseases (ILDs) is diverse and complex. Diagnosis and therapy usually pose challenges. This review describes a selection of rare and ultrarare ILDs including pulmonary alveolar proteinosis, pulmonary alveolar microlithiasis and pleuroparenchymal fibroelastosis. In addition, monogenic ILDs or ILDs in congenital syndromes and various multiple cystic lung diseases will be discussed. All these conditions are part of the scope of the European Reference Network on rare respiratory diseases (ERN-LUNG). Epidemiology, pathogenesis, diagnostics and treatment of each disease are presented.

Genetics in Idiopathic Pulmonary Fibrosis: A Clinical Perspective

BACKGROUND

Unraveling the genetic background in a significant proportion of patients with both sporadic and familial IPF provided new insights into the pathogenic pathways of pulmonary fibrosis.

AIM

The aim of the present study is to overview the clinical significance of genetics in IPF.

PERSPECTIVE

It is fascinating to realize the so-far underestimated but dynamically increasing impact that genetics has on aspects related to the pathophysiology, accurate and early diagnosis, and treatment and prevention of this devastating disease. Genetics in IPF have contributed as no other in unchaining the disease from the dogma of a "a sporadic entity of the elderly, limited to the lungs" and allowed all scientists, but mostly clinicians, all over the world to consider its many aspects and "faces" in all age groups, including its co-existence with several extra pulmonary conditions from cutaneous albinism to bone-marrow and liver failure.

CONCLUSION

By providing additional evidence for unsuspected characteristics such as immunodeficiency, impaired mucus, and surfactant and telomere maintenance that very often co-exist through the interaction of common and rare genetic variants in the same patient, genetics have created a generous and pluralistic yet unifying platform that could lead to the understanding of the injurious and pro-fibrotic effects of many seemingly unrelated extrinsic and intrinsic offending factors. The same platform constantly instructs us about our limitations as well as about the heritability, the knowledge and the wisdom that is still missing.

Hermansky-Pudlak syndrome: Gene therapy for pulmonary fibrosis

Pulmonary fibrosis is a progressive and often fatal lung disease that manifests in most patients with Hermansky-Pudlak syndrome (HPS) type 1. Although the pathobiology of HPS pulmonary fibrosis is unknown, several studies highlight the pathogenic roles of different cell types, including type 2 alveolar epithelial cells, alveolar macrophages, fibroblasts, myofibroblasts, and immune cells. Despite the identification of the HPS1 gene and progress in understanding the pathobiology of HPS pulmonary fibrosis, specific treatment for HPS pulmonary fibrosis is not available, emphasizing the need to identify cellular and molecular targets and to develop therapeutic strategies for this devastating disease. This commentary summarizes recent advances and aims to provide insights into gene therapy for HPS pulmonary fibrosis.

Automated Digital Quantification of Pulmonary Fibrosis in Human Histopathology Specimens

Pulmonary fibrosis is characterized by abnormal interstitial extracellular matrix and cellular accumulations. Methods quantifying fibrosis severity in lung histopathology samples are semi-quantitative, subjective, and analyze only portions of sections. We sought to determine whether automated computerized imaging analysis shown to continuously measure fibrosis in mice could also be applied in human samples. A pilot study was conducted to analyze a small number of specimens from patients with Hermansky-Pudlak syndrome pulmonary fibrosis (HPSPF) or idiopathic pulmonary fibrosis (IPF). Digital images of entire lung histological serial sections stained with picrosirius red and alcian blue or anti-CD68 antibody were analyzed using dedicated software to automatically quantify fibrosis, collagen, and macrophage content. Automated fibrosis quantification based on parenchymal tissue density and fibrosis score measurements was compared to pulmonary function values or Ashcroft score. Automated fibrosis quantification of HPSPF lung explants was significantly higher than that of IPF lung explants or biopsies and was also significantly higher in IPF lung explants than in IPF biopsies. A high correlation coefficient was found between some automated quantification measurements and lung function values for the three sample groups. Automated quantification of collagen content in lung sections used for digital image analyses was similar in the three groups. CD68 immunolabeled cell measurements were significantly higher in HPSPF explants than in IPF biopsies. In conclusion, computerized image analysis provides access to accurate, reader-independent pulmonary fibrosis quantification in human histopathology samples. Fibrosis, collagen content, and immunostained cells can be automatically and individually quantified from serial sections. Robust automated digital image analysis of human lung samples enhances the available tools to quantify and study fibrotic lung disease.

A family history of Hermansky-Pudlak syndrome complicated with pulmonary fibrosis: a case series and review

The Hernansky-Pudlak syndrome (HPS) is a rare genetic disorder. We report three cases from a family of 12 siblings, with six albinos, of whom four and the father had pulmonary fibrosis (PF). Case 1 was admitted to our hospital due to increasing dyspnoea and history of gynaecological bleeding. Pulmonary function test showed a restrictive airflow pattern, high-resolution computed tomographic scan demonstrated interstitial lung disease (ILD), and platelet aggregation was compromised with a reduced number of platelet dense bodies. The family history revealed endogamy and 11 members with suspected HPS. One of the albino sisters and the father had passed away with unidentified ILD, an albino brother died 14 years earlier, his autopsy had shown collections of ceroid pigments in the lungs, consistent with HPS, and another brother was followed up at our hospital for ILD and compromised platelet aggregation. This family probably has the highest number of members affected by HPS in Spain.

Hermansky-Pudlak Syndrome and Lung Disease: Pathogenesis and Therapeutics

Hermansky-Pudlak Syndrome (HPS) is a rare, genetic, multisystem disorder characterized by oculocutaneous albinism (OCA), bleeding diathesis, immunodeficiency, granulomatous colitis, and pulmonary fibrosis. HPS pulmonary fibrosis (HPS-PF) occurs in 100% of patients with subtype HPS-1 and has a similar presentation to idiopathic pulmonary fibrosis. Upon onset, individuals with HPS-PF have approximately 3 years before experiencing signs of respiratory failure and eventual death. This review aims to summarize current research on HPS along with its associated pulmonary fibrosis and its implications for the development of novel treatments. We will discuss the genetic basis of the disease, its epidemiology, and current therapeutic and clinical management strategies. We continue to review the cellular processes leading to the development of HPS-PF in alveolar epithelial cells, lymphocytes, mast cells, and fibrocytes, along with the molecular mechanisms that contribute to its pathogenesis and may be targeted in the treatment of HPS-PF. Finally, we will discuss emerging new cellular and molecular approaches for studying HPS, including lentiviral-mediated gene transfer, induced pluripotent stem cells (iPSCs), organoid and 3D-modelling, and CRISPR/Cas9-based gene editing approaches.

Hermansky-Pudlak syndrome pulmonary fibrosis: a rare inherited interstitial lung disease

Pulmonary fibrosis is a progressive interstitial lung disease of unknown aetiology with a poor prognosis. Studying genetic diseases associated with pulmonary fibrosis provides insights into the pathogenesis of the disease. Hermansky-Pudlak syndrome (HPS), a rare autosomal recessive disorder characterised by abnormal biogenesis of lysosome-related organelles, manifests with oculocutaneous albinism and excessive bleeding of variable severity. Pulmonary fibrosis is highly prevalent in three out of 10 genetic types of HPS (HPS-1, HPS-2 and HPS-4). Thus, genotyping of individuals with HPS is clinically relevant. HPS-1 tends to affect Puerto Rican individuals due to a genetic founder effect. HPS pulmonary fibrosis shares some clinical features with idiopathic pulmonary fibrosis (IPF), including dyspnoea, cough, restrictive lung physiology and computed tomography (CT) findings of fibrosis. In contrast to IPF, HPS pulmonary fibrosis generally affects children (HPS-2) or middle-aged adults (HPS-1 or HPS-4) and may be associated with ground-glass opacification in CT scans. Histopathology of HPS pulmonary fibrosis, and not IPF, shows vacuolated hyperplastic type II cells with enlarged lamellar bodies and alveolar macrophages with lipofuscin-like deposits. Antifibrotic drugs approved as treatment for IPF are not approved for HPS pulmonary fibrosis. However, lung transplantation has been performed in patients with severe HPS pulmonary fibrosis. HPS pulmonary fibrosis serves as a model for studying fibrotic lung disease and fibrosis in general.

Emodin attenuates silica-induced lung injury by inhibition of inflammation, apoptosis and epithelial-mesenchymal transition

Silicosis is a fatal pulmonary disease caused by the inhalation of silica dust, and characterized by inflammation and fibrosis of the lung, with no effective treatment to date. Here we investigate the effect of emodin, an anthraquinone derivative isolated from rhubarb using a mouse silicosis model and in vitro cultured human macrophages and alveolar epithelial cells. Results from histological examination indicated that emodin reduced the degree of alveolitis and fibrosis in the lungs of mice exposed to silica particles. We also demonstrated that emodin effectively inhibited the phosphorylation of Smad3 and NF-κB and reduced the levels of inflammatory factors in the lung tissue of mice treated with silica particles. In addition, we found that emodin inhibited apoptosis and demonstrated an anti-fibrotic effect by down-regulating the pro-apoptotic protein Bax and up-regulating the anti-apoptotic protein Bcl-2. Furthermore, emodin increased E-cadherin levels, reduced the expression of Vimentin, α-SMA and Col-I, as well as pro-inflammatory factors TGF-β1, TNF-α and IL-1β in vivo and in vitro. These results suggested that emodin can regulate epithelial-mesenchymal transition (EMT) through the inhibition of the TGF-β1/Smad3 signaling pathway and the NF-κB signaling pathway to prevent alveolar inflammation and apoptotic process. Overall, this study showed that emodin can alleviate pulmonary fibrosis in silicosis through regulating the inflammatory response and fibrotic process at multiple levels.

Familial Interstitial Lung Disease

The interstitial lung diseases (ILDs) are a group of progressive disorders characterized by chronic inflammation and/or fibrosis in the lung. While some ILDs can be linked to specific environmental causes (i.e., asbestosis, silicosis), in many individuals, no culprit exposure can be identified; these patients are deemed to have "idiopathic interstitial pneumonia" (IIP). Family history is now recognized as the strongest risk factor for IIP, and IIP cases that run in families comprise a syndrome termed "familial interstitial pneumonia" (FIP). Mutations in more than 10 different genes have been implicated as responsible for disease in FIP families. Diverse ILD clinical phenotypes can be seen within a family, and available evidence suggests underlying genetic risk is the primary determinant of disease outcomes. Together, these FIP studies have provided unique insights into the pathobiology of ILDs, and brought focus on the unique issues that arise in the care of patients with FIP.

Hermansky-Pudlak syndrome: Mutation update

Hermansky-Pudlak syndrome (HPS) is a group of 10 autosomal recessive multisystem disorders, each defined by the deficiency of a specific gene. HPS-associated genes encode components of four ubiquitously expressed protein complexes: Adaptor protein-3 (AP-3) and biogenesis of lysosome-related organelles complex-1 (BLOC-1) through -3. All individuals with HPS exhibit albinism and a bleeding diathesis; additional features occur depending on the defective protein complex. Pulmonary fibrosis is associated with AP-3 and BLOC-3 deficiency, immunodeficiency with AP-3 defects, and gastrointestinal symptoms are more prevalent and severe in BLOC-3 deficiency. Therefore, identification of the HPS subtype is valuable for prognosis, clinical management, and treatment options. The prevalence of HPS is estimated at 1-9 per 1,000,000. Here we summarize 264 reported and novel variants in 10 HPS genes and estimate that ~333 Puerto Rican HPS subjects and ~385 with other ethnicities are reported to date. We provide pathogenicity predictions for missense and splice site variants and list variants with high minor allele frequencies. Current cellular and clinical aspects of HPS are also summarized. This review can serve as a manifest for molecular diagnostics and genetic counseling aspects of HPS.

Possible value of antifibrotic drugs in patients with progressive fibrosing non-IPF interstitial lung diseases

BACKGROUND

Fibrosing, non-idiopathic pulmonary fibrosis (non-IPF) interstitial lung diseases (fILDs) are a heterogeneous group of diseases characterized by a different amount of inflammation and fibrosis. Therapy is currently based on corticosteroids and/or immunomodulators. However, response to these therapies is highly variable, sometimes without meaningful improvement, especially in more fibrosing forms. Pirfenidone and nintedanib have recently demonstrated to reduce functional decline in patients with IPF. However, their antifibrotic mechanism makes these two drugs an interesting approach for treatment of fibrosing ILDs other than IPF.

OBJECTIVES

We here report our experience with antifibrotic drugs in fibrosing non-IPF ILDs patients having a progressive phenotype during immunosuppressive therapy.

METHODS

Patients with a multidisciplinary team diagnosis of fibrosing non-IPF ILDs experiencing a progressive phenotype during treatment with corticosteroids and/or immunomodulators between October-2014 and January-2018 at our tertiary referral Center for ILDs were retrospectively analyzed. Antifibrotic therapy was administered after application with the respective health insurance company and after consent by the patient. Pulmonary-function-tests and follow-up visits were performed every 6 ± 1 months.

RESULTS

Eleven patients were treated with antifibrotic drugs (8 males, mean age 62 ± 12.8 years, mean FVC% 62.8 ± 22.3, mean DLCO% 35.5 ± 10.7, median follow-up under antifibrotic treatment 11.1 months). Patients had a diagnosis of unclassifiable ILD in 6 cases, pleuroparenchymal fibroelastosis in 2 cases, idiopathic-NSIP in 1 case, asbestos-related ILD in 1 case and Hermansky-Pudlak syndrome in 1 case. Treatment before antifibrotics consisted of corticosteroids in all patients: 5 combined with Azathioprin, 1 with either methotrexate or cyclophosphamide (i.v.). Ten patients were treated with pirfenidone (2403 mg/die) and 1 with nintedanib (300 mg/die). Median FVC was 56, 56, 50%, at time points - 24, - 12, - 6 before initiation, 44% at time of initiation and 46.5% at 6 months after initiation of antifibrotic treatment. Antifibrotic treatment was generally well tolerated with a need of dose reduction in 2 cases (rash and nausea) and early termination in 3 cases.

CONCLUSIONS

Antifibrotic treatment may be a valuable treatment option in patients with progressive fibrosing non-IPF ILD if currently no other treatment options exist. However, prospective, randomized clinical trials are urgently needed to assess the real impact of antifibrotic therapy in these patients.

A novel mutation causes Hermansky-Pudlak syndrome type 4 with pulmonary fibrosis in 2 siblings from China

Hermansky-Pudlak syndrome (HPS) is a rare autosomal recessive multisystem disorder characterized by oculocutaneous albinism (OCA) and bleeding diathesis, although it displays both genetic and phenotypic heterogeneity. Several genetic subtypes of HPS have been identified in human; however, the characterizations of HPS type 4 (HPS-4) genotype and phenotype remain unclear. This study was aimed to identify gene mutation responsible for HPS-4 with pulmonary fibrosis (PF).Two Chinese siblings in their 50 s afflicted with OCA and progressive dyspnea were recruited and underwent clinical and genetic examinations. In both patients, chest high-resolution computerized tomography showed severe interstitial PF in bilateral lung fields, and the pulmonary function test indicated restrictive lung disease. A novel homozygous frameshift mutation (NM_022081: c.630dupC; p.A211fs) in the HPS4 gene was identified by whole-exome sequencing analysis followed by Sanger DNA sequencing, and it segregated with the phenotypes. The c.630dupC mutation was not found in unaffected healthy controls. The patients were considered as HPS-4 with interstitial PF and eventually died of respiratory failure.This is the first report on the genotype and clinical phenotype of HPS-4 in China. Our results demonstrate the association between a novel frameshift mutation in HPS4 and severe PF with poor prognosis in HPS is presented.

Hermansky-Pudlak syndrome and oculocutaneous albinism in Chinese children with pigmentation defects and easy bruising

Background

Determining the etiology of oculocutaneous albinism is important for proper clinical management and to determine prognosis. The purpose of this study was to genotype and phenotype eight adopted Chinese children who presented with oculocutaneous albinism and easy bruisability.

Results

The patients were evaluated at a single center; their ages ranged from 3 to 8 years. Whole exome or direct sequencing showed that two of the children had Hermansky-Pudlak syndrome (HPS) type-1 (HPS-1), one had HPS-3, one had HPS-4, and four had non-syndromic oculocutaneous albinism associated with TYR variants (OCA1). Two frameshift variants in HPS1 (c.9delC and c.1477delA), one nonsense in HPS4 (c.416G > A), and one missense variant in TYR (c.1235C > T) were unreported. The child with HPS-4 is the first case with this subtype reported in the Chinese population. Hypopigmentation in patients with HPS was mild compared to that in OCA1 cases, who had severe pigment defects. Bruises, which may be more visible in patients with hypopigmentation, were found in all cases with either HPS or OCA1. Whole mount transmission electron microscopy demonstrated absent platelet dense granules in the HPS cases; up to 1.9 mean dense granules per platelet were found in those with OCA1. Platelet aggregation studies in OCA1 cases were inconclusive.

Conclusions

Clinical manifestations of oculocutaneous albinism and easy bruisability may be observed in children with HPS or OCA1. Establishing definitive diagnoses in children presenting with these phenotypic features is facilitated by genetic testing. Non-syndromic oculocutaneous albinism and various HPS subtypes, including HPS-4, are found in children of Chinese ancestry.