Inhaled recombinant GM-CSF reduces the need for whole lung lavage and improves gas exchange in autoimmune pulmonary alveolar proteinosis patients.

RATIONALE: Whole lung lavage (WLL) is a widely accepted palliative treatment for autoimmune pulmonary alveolar proteinosis (aPAP) but does not correct myeloid cell dysfunction or reverse the pathological accumulation of surfactant. In contrast, inhaled recombinant granulocyte-macrophage colony-stimulating factor (rGM-CSF) is a promising pharmacological approach that restores alveolar macrophage functions including surfactant clearance. Here, we evaluate WLL followed by inhaled rGM-CSF (sargramostim) as therapy of aPAP. METHODS: 18 patients with moderate-to-severe aPAP were enrolled, received baseline WLL, were randomised into either the rGM-CSF group (receiving inhaled sargramostim) or control group (no scheduled therapy) and followed for 30 months after the baseline WLL. Outcome measures included additional unscheduled "rescue" WLL for disease progression, assessment of arterial blood gases, pulmonary function, computed tomography, health status, biomarkers and adverse events. Patients requiring rescue WLL were considered to have failed their assigned intervention group. RESULTS: The primary end-point of time to first rescue WLL was longer in rGM-CSF-treated patients than controls (30 versus 18 months, n=9 per group, p=0.0078). Seven control patients (78%) and only one rGM-CSF-treated patient (11%) required rescue WLL, demonstrating a 7-fold increase in relative risk (p=0.015). Compared to controls, rGM-CSF-treated patients also had greater improvement in peripheral arterial oxygen tension, alveolar-arterial oxygen tension difference, diffusing capacity of the lungs for carbon monoxide and aPAP biomarkers. One patient from each group withdrew for personal reasons. No serious adverse events were reported. CONCLUSIONS: This long-term, prospective, randomised trial demonstrated inhaled sargramostim following WLL reduced the requirement for WLL, improved lung function and was safe in aPAP patients. WLL plus inhaled sargramostim may be useful as combined therapy for aPAP.

Phenotypes of organ involvement in sarcoidosis.

Sarcoidosis is a highly variable, systemic granulomatous disease of hitherto unknown aetiology. The GenPhenReSa (Genotype-Phenotype Relationship in Sarcoidosis) project represents a European multicentre study to investigate the influence of genotype on disease phenotypes in sarcoidosis.The baseline phenotype module of GenPhenReSa comprised 2163 Caucasian patients with sarcoidosis who were phenotyped at 31 study centres according to a standardised protocol.From this module, we found that patients with acute onset were mainly female, young and of Scadding type I or II. Female patients showed a significantly higher frequency of eye and skin involvement, and complained more of fatigue. Based on multidimensional correspondence analysis and subsequent cluster analysis, patients could be clearly stratified into five distinct, yet undescribed, subgroups according to predominant organ involvement: 1) abdominal organ involvement, 2) ocular-cardiac-cutaneous-central nervous system disease involvement, 3) musculoskeletal-cutaneous involvement, 4) pulmonary and intrathoracic lymph node involvement, and 5) extrapulmonary involvement.These five new clinical phenotypes will be useful to recruit homogenous cohorts in future biomedical studies.

A large kindred of pulmonary fibrosis associated with a novel ABCA3 gene variant.

BACKGROUND: Interstitial lung disease occurring in children is a condition characterized by high frequency of cases due to genetic aberrations of pulmonary surfactant homeostasis, that are also believed to be responsible of a fraction of familial pulmonary fibrosis. To our knowledge, ABCA3 gene was not previously reported as causative agent of fibrosis affecting both children and adults in the same kindred. METHODS: We investigated a large kindred in which two members, a girl whose interstitial lung disease was first recognized at age of 13, and an adult, showed a diffuse pulmonary fibrosis with marked differences in terms of morphology and imaging. An additional, asymptomatic family member was detected by genetic analysis. Surfactant abnormalities were investigated at biochemical, and genetic level, as well as by cell transfection experiments. RESULTS: Bronchoalveolar lavage fluid analysis of the patients revealed absence of surfactant protein C, whereas the gene sequence was normal. By contrast, sequence of the ABCA3 gene showed a novel homozygous G > A transition at nucleotide 2891, localized within exon 21, resulting in a glycine to aspartic acid change at codon 964. Interestingly, the lung specimens from the girl displayed a morphologic usual interstitial pneumonitis-like pattern, whereas the specimens from one of the two adult patients showed rather a non specific interstitial pneumonitis-like pattern. CONCLUSIONS: We have detected a large kindred with a novel ABCA3 mutation likely causing interstitial lung fibrosis affecting either young and adult family members. We suggest that ABCA3 gene should be considered in genetic testing in the occurrence of familial pulmonary fibrosis.

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.

Physical properties, lung deposition modeling, and bioactivity of recombinant GM-CSF aerosolised with a highly efficient nebulizer.

Pulmonary alveolar proteinosis (PAP) is a rare condition characterized by the accumulation of lipoproteinaceous material within air spaces. Although whole lung lavage is the current standard of care, recent advances in our understanding of PAP pathophysiology suggest that the disorder may benefit from inhalation of recombinant granulocyte-macrophage colony-stimulating factor (rGM-CSF). The aim of this study was to determine the physical properties and bioactivity of rGM-CSF aerosolised by the highly efficient AKITA² APIXNEB® nebulizer system. The physical properties of aerosolised rGM-CSF were investigated in terms of droplet size, output and output rate by laser diffraction and gravimetrical analysis. Lung deposition was assessed using deposition modeling (ICRP). Molecular mass before and after aerosolisation was determined by SDS-PAGE, while the bioactivity of rGM-CSF was evaluated by measuring the GM-CSF-stimulated increase in pSTAT5 using mAM-hGM-R cells. Ninety-six % of the rGM-CSF filling dose was aerosolised with the Akita² Apixneb® nebulizer system. Particle size was highly reproducible, and the amount deposited within the lung was 80.35% of the delivered dose. The aerosolisation did not alter the molecular structure of rGM-CSF, nor its ability to stimulate the pSTAT5, which increased by 99.5%, similar to values for rGM-CSF prior to aerosolisation. We conclude that the highly efficient AKITA² APIXNEB® nebulizer system is likely to efficaciously deliver rGM-CSF to the airways of patients with autoimmune PAP.

Relationship between diffuse pulmonary fibrosis, alveolar proteinosis, and granulocyte-macrophage colony stimulating factor autoantibodies.

Extensive pulmonary fibrosis is a rare occurrence in pulmonary alveolar proteinosis. We report 2 cases that have interesting implications. A female patient was diagnosed with autoimmune pulmonary alveolar proteinosis that evolved over 7 years into diffuse fibrosis. In a male patient with diffuse fibrosis we incidentally detected electron microscopic features of alveolar surfactant accumulation and positive autoantibodies to granulocyte-macrophage colony stimulating factor. In the male patient we speculated that the pulmonary fibrosis might have been preceded by an asymptomatic phase of autoimmune pulmonary alveolar proteinosis, and that we should investigate the involvement of surfactant dysfunction in the pathogenesis of fibrotic lung disease.

CT-guided biopsy in the differential diagnosis of Sjogren syndrome associated cystic lung disease: A case of lung nodular AL-k amyloidosis.

Pulmonary involvement in Sjogren syndrome (SS) could manifest as cystic lung disease (CLD). CLD in SS includes lymphocytic interstitial pneumonia (LIP) and pulmonary amyloidosis. Differential diagnosis usually requires surgical lung biopsy, whereas CT-guided percutaneous fine needle aspiration biopsy (CT-FNAB) has not yet explored. We describe the case of a 63-year-old never smoker Caucasian female with a SS diagnosis who displayed a newly detected diffuse CLD at high-resolution computed tomography, though totally asymptomatic. Given the favorable location of one big lesion at the superior left lobe, a CT-FNAB was proposed instead of a more invasive SLB. At histology examination a diagnosis of pulmonary nodular AL kappa amyloidosis in the context of SS was established. In conclusion, CT-FNAB might represent an alternative and less invasive diagnostic procedure than SLB in the differential diagnosis of CLD, even if further research is needed. Moreover, this case presents an unusual association between SS and pulmonary nodular AL kappa amyloidosis, with pulmonary nodules and cysts without systemic manifestations.

Multidisciplinary Approach in the Early Detection of Undiagnosed Connective Tissue Diseases in Patients With Interstitial Lung Disease: A Retrospective Cohort Study.

Interstitial lung disease (ILD) encompasses a wide range of parenchymal lung pathologies with different clinical, histological, radiological, and serological features. Follow-up, treatment, and prognosis are strongly influenced by the underlying pathogenesis. Considering that an ILD may complicate the course of any connective tissue disease (CTD) and that CTD's signs are not always easily identifiable, it could be useful to screen every ILD patient for a possible CTD. The recent definition of interstitial pneumonia with autoimmune features is a further confirmation of the close relationship between CTD and ILD. In this context, the multidisciplinary approach is assuming a growing and accepted role in the correct diagnosis and follow-up, to as early as possible define the best therapeutic strategy. However, despite clinical advantages, until now, the pathways of the multidisciplinary approach in ILD patients are largely heterogeneous across different centers and the best strategy to apply is still to be established and validated. Aims of this article are to describe the organization of our multidisciplinary group for ILD, which is mainly focused on the early identification and management of CTD in patients with ILD and to show our results in a 1 year period of observation. We found that 15% of patients referred for ILD had an underlying CTD, 33% had interstitial pneumonia with autoimmune feature, and 52% had ILD without detectable CTD. Furthermore, we demonstrated that the adoption of a standardized strategy consisting of a screening questionnaire, specific laboratory tests, and nailfold videocapillaroscopy in all incident ILD proved useful in making the right diagnosis.

Assessment and management of pulmonary alveolar proteinosis in a reference center.

Pulmonary alveolar proteinosis (PAP) is a term defining an ultra-rare group of disorders characterised by a perturbation in surfactant homeostasis, resulting in its accumulation within airspaces and impaired gas transfer. In this report we provide data from a cohort of PAP patients (n=81) followed for more than two decades at the San Matteo University Hospital of Pavia, Italy. In agreement with other large series in PAP individuals, 90% of the study subjects were affected by autoimmune/idiopathic PAP, while the remaining subjects were divided as follow: congenital 1%, secondary 4% and PAP-like 5%. The disease affected males and females with a ratio of 2:1 and approximately one third of PAP patients were lifelong nonsmokers. Occupational exposure was reported in 35% of subjects in this series. With reference to the PAP clinical course, in 29 patients (7% with spontaneous remission) disease severity did not necessitate whole lung lavage (WLL) in the long-term follow up. On the other hand, 44 PAP patients underwent therapeutic WLL: in 31 subjects a single WLL was sufficient to provide long term, durable benefit, whereas 13 patients required multiple WLLs. The intra-patient mean interval between two consecutive WLLs was 15.7±13.6 months. When baseline data among never lavaged and PAP patients lavaged at least once were compared, the need for lavage was significantly associated with serum biomarkers (CEA, Cyfra, LDH), lung function parameters forced vital capacity (FVC), and lung diffusing capacity (Dlco). We conclude that patient cohorts with an ultra-rare disease, such as PAP, referred to a single reference center, can provide useful information on the natural history and clinical course of the disease.

Pulmonary alveolar proteinosis: diagnostic and therapeutic challenges.

Pulmonary Alveolar Proteinosis (PAP) is a rare syndrome characterized by pulmonary surfactant accumulation within the alveolar spaces. It occurs with a reported prevalence of 0.1 per 100,000 individuals and in distinct clinical forms: autoimmune (previously referred to as the idiopathic form, represents the vast majority of PAP cases, and is associated with Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF) auto-antibodies; GMAbs), secondary (is a consequence of underlying disorders), congenital (caused by mutations in the genes encoding for the GM-CSF receptor), and PAP-like syndromes (disorders associated with surfactant gene mutations). The clinical course of PAP is variable, ranging from spontaneous remission to respiratory failure. Whole lung lavage (WLL) is the current standard treatment for PAP patients and although it is effective in the majority of cases, disease persistence is not an unusual outcome, even if disease is well controlled by WLL.In this paper we review the therapeutic strategies which have been proposed for the treatment of PAP patients and the progress which has been made in the understanding of the disease pathogenesis.

C reactive protein and alpha1-antitrypsin: relationship between levels and gene variants.

The first step in laboratory diagnosis of alpha1-antitrypsin deficiency (AATD) is the determination of alpha1-antitrypsin (AAT) serum levels; these levels in turn are influenced by the inflammatory status. C reactive protein (CRP) has been proposed as a marker of systemic inflammation. Single nucleotide polymorphisms (SNPs) in the CRP gene have been associated with differences in baseline CRP levels. The purpose of this study was to investigate the relationship between CRP and AAT in the AATD diagnostic setting and to verify whether variations in the CRP gene could influence CRP. We determined AAT and CRP levels in 362 consecutive dried blood spot (DBS) samples submitted for AATD diagnosis and genotyped 3 CRP gene SNPs (rs1205, rs3093077, and rs3091244) associated with variations in serum CRP concentrations. To this aim, we developed a method to measure CRP in a DBS with a good correlation with CRP measurement in serum (r2=0.9927). We showed then that systemic inflammatory status parallels increased levels of AAT (80% of subjects with intermediate AATD and a CRP>0.8 mg/dL had an AAT level above the cut-off of 113 mg/dL) and that this increase might mask the presence of AATD variants. No association was detected between CRP levels and the 3 CRP gene polymorphisms. Simultaneous determination of CRP and AAT is useful in the correct diagnosis of heterozygotes carrying intermediate AATD genotypes; their genetic influence on the CRP level is negligible.

Therapy options in pulmonary alveolar proteinosis.

Pulmonary alveolar proteinosis is a rare condition characterized by the accumulation of lipoproteinaceous material within the airspaces, resulting in impaired gas transfer, and clinical manifestations ranging from asymptomatic to severe respiratory failure. To the best of the authors' knowledge, there are only a few conditions whose natural history has been so dramatically changed by the influence of advances in basic science, clinical medicine, and translational research in therapeutic approaches. Whole-lung lavage is the current standard of care and it plays a critical role as a modifier factor of the natural history of proteinosis. That notwithstanding, the identification of autoantibodies neutralizing granulocyte-macrophage colony-stimulating factor in serum and lung of patients affected by the form of proteinosis previously referred to as idiopathic, has opened the way to novel therapeutic options, such as supplementation of exogenous granulocyte-macrophage colony-stimulating factor, or strategies aimed at reducing the levels of the autoantibodies. The aim of this paper is to provide an updated review of the current therapeutic approach to proteinosis.

The problems of clinical trials and registries in rare diseases.

Clinical trials to evaluate patients affected by rare diseases are often hampered by the difficulty of recruiting a critical sample size. Registries for rare conditions are thus extremely powerful tools for overcoming recruitment problems. Here we present and discuss the international experience with alpha1-antitrypsin deficiency achieved by the Alpha One International Registry, and national experience obtained with a large series of patients with pulmonary alveolar proteinosis.

In Lysinuric Protein Intolerance system y+L activity is defective in monocytes and in GM-CSF-differentiated macrophages.

BACKGROUND: In the recessive aminoaciduria Lysinuric Protein Intolerance (LPI), mutations of SLC7A7/y+LAT1 impair system y+L transport activity for cationic amino acids. A severe complication of LPI is a form of Pulmonary Alveolar Proteinosis (PAP), in which alveolar spaces are filled with lipoproteinaceous material because of the impaired surfactant clearance by resident macrophages. The pathogenesis of LPI-associated PAP remains still obscure. The present study investigates for the first time the expression and function of y+LAT1 in monocytes and macrophages isolated from a patient affected by LPI-associated PAP. A comparison with mesenchymal cells from the same subject has been also performed. METHODS: Monocytes from peripheral blood were isolated from a 21-year-old patient with LPI. Alveolar macrophages and fibroblastic-like mesenchymal cells were obtained from a whole lung lavage (WLL) performed on the same patient. System y+L activity was determined measuring the 1-min uptake of [3H]-arginine under discriminating conditions. Gene expression was evaluated through qRT-PCR. RESULTS: We have found that: 1) system y+L activity is markedly lowered in monocytes and alveolar macrophages from the LPI patient, because of the prevailing expression of SLC7A7/y+LAT1 in these cells; 2) on the contrary, fibroblasts isolated from the same patient do not display the transport defect due to compensation by the SLC7A6/y+LAT2 isoform; 3) in both normal and LPI monocytes, GM-CSF induces the expression of SLC7A7, suggesting that the gene is a target of the cytokine; 4) GM-CSF-induced differentiation of LPI monocytes is comparable to that of normal cells, demonstrating that GM-CSF signalling is unaltered; 5) general and respiratory conditions of the patient, along with PAP-associated parameters, markedly improved after GM-CSF therapy through aerosolization. CONCLUSIONS: Monocytes and macrophages, but not fibroblasts, derived from a LPI patient clearly display the defect in system y+L-mediated arginine transport. The different transport phenotypes are referable to the relative levels of expression of SLC7A7 and SLC7A6. Moreover, the expression of SLC7A7 is regulated by GM-CSF in monocytes, pointing to a role of y+LAT1 in the pathogenesis of LPI associated PAP.