A Comparison of Usage and Outcomes Between Nurse Practitioner and Resident-Staffed Medical ICUs.

OBJECTIVE: To compare usage patterns and outcomes of a nurse practitioner-staffed medical ICU and a resident-staffed physician medical ICU. DESIGN: Retrospective chart review of 1,157 medical ICU admissions from March 2012 to February 2013. SETTING: Large urban academic university hospital. SUBJECTS: One thousand one hundred fifty-seven consecutive medical ICU admissions including 221 nurse practitioner-staffed medical ICU admissions (19.1%) and 936 resident-staffed medical ICU admissions (80.9%). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Data obtained included age, gender, race, medical ICU admitting diagnosis, location at time of ICU transfer, code status at ICU admission, and severity of illness using both Acute Physiology and Chronic Health Evaluation II scores and a model for relative expected mortality. Primary outcomes compared included ICU mortality, in-hospital mortality, medical ICU length of stay, and post-ICU discharge hospital length of stay. Patients admitted to the nurse practitioner-staffed medical ICU were older (63 ± 16.5 vs 59.2 ± 16.9 yr for resident-staffed medical ICU; p = 0.019), more likely to be transferred from an inpatient unit (52.0% vs 40.0% for the resident-staffed medical ICU; p = 0.002), and had a higher severity of illness by relative expected mortality (21.3 % vs 17.2 % for the resident-staffed medical ICU; p = 0.001). There were no differences among primary outcomes except for medical ICU length of stay (nurse practitioner-resident-staffed 7.9 ± 7.5 d vs resident-staffed medical ICU 5.6 ± 6.5 d; p = 0.0001). Post-hospital discharge to nonhome location was also significantly higher in the nurse practitioner-ICU (31.7% in nurse practitioner-staffed medical ICU vs 23.9% in resident-staffed medical ICU; p = 0.24). CONCLUSIONS: We found no difference in mortality between an nurse practitioner-staffed medical ICU and a resident-staffed physician medical ICU. Our study adds further evidence that advanced practice providers can render safe and effective ICU care.

Sarcoidosis activates diverse transcriptional programs in bronchoalveolar lavage cells.

BACKGROUND: Sarcoidosis is a multisystem immuno-inflammatory disorder of unknown etiology that most commonly involves the lungs. We hypothesized that an unbiased approach to identify pathways activated in bronchoalveolar lavage (BAL) cells can shed light on the pathogenesis of this complex disease. METHODS: We recruited 15 patients with various stages of sarcoidosis and 12 healthy controls. All subjects underwent bronchoscopy with lavage. For each subject, total RNA was extracted from BAL cells and hybridized to an Affymetrix U133A microarray. Rigorous statistical methods were applied to identify differential gene expression between subjects with sarcoidosis vs. CONTROLS: To better elucidate pathways differentially activated between these groups, we integrated network and gene set enrichment analyses of BAL cell transcriptional profiles. RESULTS: Sarcoidosis patients were either non-smokers or former smokers, all had lung involvement and only two were on systemic prednisone. Healthy controls were all non-smokers. Comparison of BAL cell gene expression between sarcoidosis and healthy subjects revealed over 1500 differentially expressed genes. Several previously described immune mediators, such as interferon gamma, were upregulated in the sarcoidosis subjects. Using an integrative computational approach we constructed a modular network of over 80 gene sets that were highly enriched in patients with sarcoidosis. Many of these pathways mapped to inflammatory and immune-related processes including adaptive immunity, T-cell signaling, graft vs. host disease, interleukin 12, 23 and 17 signaling. Additionally, we uncovered a close association between the proteasome machinery and adaptive immunity, highlighting a potentially important and targetable relationship in the pathobiology of sarcoidosis. CONCLUSIONS: BAL cells in sarcoidosis are characterized by enrichment of distinct transcriptional programs involved in immunity and proteasomal processes. Our findings add to the growing evidence implicating alveolar resident immune effector cells in the pathogenesis of sarcoidosis and identify specific pathways whose activation may modulate disease progression.

Lung cancer screening beyond low-dose computed tomography: the role of novel biomarkers.

Lung cancer is the most common and lethal malignancy in the world. The landmark National lung screening trial (NLST) showed a 20% relative reduction in mortality in high-risk individuals with screening low-dose computed tomography. However, the poor specificity and low prevalence of lung cancer in the NLST provide major limitations to its widespread use. Furthermore, a lung nodule on CT scan requires a nuanced and individualized approach towards management. In this regard, advances in high through-put technology (molecular diagnostics, multi-gene chips, proteomics, and bronchoscopic techniques) have led to discovery of lung cancer biomarkers that have shown potential to complement the current screening standards. Early detection of lung cancer can be achieved by analysis of biomarkers from tissue samples within the respiratory tract such as sputum, saliva, nasal/bronchial airway epithelial cells and exhaled breath condensate or through peripheral biofluids such as blood, serum and urine. Autofluorescence bronchoscopy has been employed in research setting to identify pre-invasive lesions not identified on CT scan. Although these modalities are not yet commercially available in clinic setting, they will be available in the near future and clinicians who care for patients with lung cancer should be aware. In this review, we present up-to-date state of biomarker development, discuss their clinical relevance and predict their future role in lung cancer management.

Alveolar macrophages of GM-CSF knockout mice exhibit mixed M1 and M2 phenotypes.

BACKGROUND: Activin A is a pleiotrophic regulatory cytokine, the ablation of which is neonatal lethal. Healthy human alveolar macrophages (AMs) constitutively express activin A, but AMs of patients with pulmonary alveolar proteinosis (PAP) are deficient in activin A. PAP is an autoimmune lung disease characterized by neutralizing autoantibodies to Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF). Activin A can be stimulated, however, by GM-CSF treatment of AMs in vitro. To further explore pulmonary activin A regulation, we examined AMs in bronchoalveolar lavage (BAL) from wild-type C57BL/6 compared to GM-CSF knockout mice which exhibit a PAP-like histopathology. Both human PAP and mouse GM-CSF knockout AMs are deficient in the transcription factor, peroxisome proliferator activated receptor gamma (PPARγ). RESULTS: In sharp contrast to human PAP, activin A mRNA was elevated in mouse GM-CSF knockout AMs, and activin A protein was increased in BAL fluid. Investigation of potential causative factors for activin A upregulation revealed intrinsic overexpression of IFNγ, a potent inducer of the M1 macrophage phenotype, in GM-CSF knockout BAL cells. IFNγ mRNA was not elevated in PAP BAL cells. In vitro studies confirmed that IFNγ stimulated activin A in wild-type AMs while antibody to IFNγ reduced activin A in GM-CSF knockout AMs. Both IFNγ and Activin A were also reduced in GM-CSF knockout mice in vivo after intratracheal instillation of lentivirus-PPARγ compared to control lentivirus vector. Examination of other M1 markers in GM-CSF knockout mice indicated intrinsic elevation of the IFNγ-regulated gene, inducible Nitrogen Oxide Synthetase (iNOS), CCL5, and interleukin (IL)-6 compared to wild-type. The M2 markers, IL-10 and CCL2 were also intrinsically elevated. CONCLUSIONS: Data point to IFNγ as the primary upregulator of activin A in GM-CSF knockout mice which in addition, exhibit a unique mix of M1-M2 macrophage phenotypes.

Carbon nanotube-induced pulmonary granulomatous disease: Twist1 and alveolar macrophage M1 activation.

Sarcoidosis, a chronic granulomatous disease of unknown cause, has been linked to several environmental risk factors, among which are some that may favor carbon nanotube formation. Using gene array data, we initially observed that bronchoalveolar lavage (BAL) cells from sarcoidosis patients displayed elevated mRNA of the transcription factor, Twist1, among many M1-associated genes compared to healthy controls. Based on this observation we hypothesized that Twist1 mRNA and protein expression might become elevated in alveolar macrophages from animals bearing granulomas induced by carbon nanotube instillation. To address this hypothesis, wild-type and macrophage-specific peroxisome proliferator-activated receptor gamma (PPARγ) knock out mice were given oropharyngeal instillation of multiwall carbon nanotubes (MWCNT). BAL cells obtained 60 days later exhibited significantly elevated Twist1 mRNA expression in granuloma-bearing wild-type or PPARγ knock out alveolar macrophages compared to sham controls. Overall, Twist1 expression levels in PPARγ knock out mice were higher than those of wild-type. Concurrently, BAL cells obtained from sarcoidosis patients and healthy controls validated gene array data: qPCR and protein analysis showed significantly elevated Twist1 in sarcoidosis compared to healthy controls. In vitro studies of alveolar macrophages from healthy controls indicated that Twist1 was inducible by classical (M1) macrophage activation stimuli (LPS, TNFα) but not by IL-4, an inducer of alternative (M2) macrophage activation. Findings suggest that Twist1 represents a PPARγ-sensitive alveolar macrophage M1 biomarker which is induced by inflammatory granulomatous disease in the MWCNT model and in human sarcoidosis.

Rituximab therapy in pulmonary alveolar proteinosis improves alveolar macrophage lipid homeostasis.

RATIONALE: Pulmonary Alveolar Proteinosis (PAP) patients exhibit an acquired deficiency of biologically active granulocyte-macrophage colony stimulating factor (GM-CSF) attributable to GM-CSF specific autoantibodies. PAP alveolar macrophages are foamy, lipid-filled cells with impaired surfactant clearance and markedly reduced expression of the transcription factor peroxisome proliferator-activated receptor gamma (PPARγ) and the PPARγ-regulated ATP binding cassette (ABC) lipid transporter, ABCG1. An open label proof of concept Phase II clinical trial was conducted in PAP patients using rituximab, a chimeric murine-human monoclonal antibody directed against B lymphocyte specific antigen CD20. Rituximab treatment decreased anti-GM-CSF antibody levels in bronchoalveolar lavage (BAL) fluid, and 7/9 patients completing the trial demonstrated clinical improvement as measured by arterial blood oxygenation. OBJECTIVES: This study sought to determine whether rituximab therapy would restore lipid metabolism in PAP alveolar macrophages. METHODS: BAL samples were collected from patients pre- and 6-months post-rituximab infusion for evaluation of mRNA and lipid changes. RESULTS: Mean PPARγ and ABCG1 mRNA expression increased 2.8 and 5.3-fold respectively (p ≤ 0.05) after treatment. Lysosomal phospholipase A2 (LPLA2) (a key enzyme in surfactant degradation) mRNA expression was severely deficient in PAP patients pre-treatment but increased 2.8-fold post-treatment. In supplemental animal studies, LPLA2 deficiency was verified in GM-CSF KO mice but was not present in macrophage-specific PPARγ KO mice compared to wild-type controls. Oil Red O intensity of PAP alveolar macrophages decreased after treatment, indicating reduced intracellular lipid while extracellular free cholesterol increased in BAL fluid. Furthermore, total protein and Surfactant protein A were significantly decreased in the BAL fluid post therapy. CONCLUSIONS: Reduction in GM-CSF autoantibodies by rituximab therapy improves alveolar macrophage lipid metabolism by increasing lipid transport and surfactant catabolism. Mechanisms may involve GM-CSF stimulation of alveolar macrophage ABCG1 and LPLA2 activities by distinct pathways.

Novel murine model of chronic granulomatous lung inflammation elicited by carbon nanotubes.

Lung granulomas are associated with numerous conditions, including inflammatory disorders, exposure to environmental pollutants, and infection. Osteopontin is a chemotactic cytokine produced by macrophages, and is implicated in extracellular matrix remodeling. Furthermore, osteopontin is up-regulated in granulomatous disease, and osteopontin null mice exhibit reduced granuloma formation. Animal models currently used to investigate chronic lung granulomatous inflammation bear a pathological resemblance, but lack the chronic nature of human granulomatous disease. Carbon nanoparticles are generated as byproducts of combustion. Interestingly, experimental exposures to carbon nanoparticles induce pulmonary granuloma-like lesions. However, the recruited cellular populations and extracellular matrix gene expression profiles within these lesions have not been explored. Because of the rapid resolution of granulomas in current animal models, the mechanisms responsible for persistence have been elusive. To overcome the limitations of previous models, we investigated whether a model using multiwall carbon nanoparticles would resemble chronic human lung granulomatous inflammation. We hypothesized that pulmonary exposure to multiwall carbon nanoparticles would induce granulomas, elicit a macrophage and T-cell response, and mimic other granulomatous disorders with an up-regulation of osteopontin. This model demonstrates: (1) granulomatous inflammation, with macrophage and T-cell infiltration; (2) resemblance to the chronicity of human granulomas, with persistence up to 90 days; and (3) a marked elevation of osteopontin, metalloproteinases, and cell adhesion molecules in granulomatous foci isolated by laser-capture microdissection and in alveolar macrophages from bronchoalveolar lavage. The establishment of such a model provides an important platform for mechanistic studies on the persistence of granuloma.

Restoration of PPARγ reverses lipid accumulation in alveolar macrophages of GM-CSF knockout mice.

Pulmonary alveolar proteinosis (PAP) is a lung disease characterized by a deficiency of functional granulocyte macrophage colony-stimulating factor (GM-CSF) resulting in surfactant accumulation and lipid-engorged alveolar macrophages. GM-CSF is a positive regulator of PPARγ that is constitutively expressed in healthy alveolar macrophages. We previously reported decreased PPARγ and ATP-binding cassette transporter G1 (ABCG1) levels in alveolar macrophages from PAP patients and GM-CSF knockout (KO) mice, suggesting PPARγ and ABCG1 involvement in surfactant catabolism. Because ABCG1 represents a PPARγ target, we hypothesized that PPARγ restoration would increase ABCG1 and reduce macrophage lipid accumulation. Upregulation of PPARγ was achieved using a lentivirus expression system in vivo. GM-CSF KO mice received intratracheal instillation of lentivirus (lenti)-PPARγ or control lenti-eGFP. Ten days postinstillation, 79% of harvested alveolar macrophages expressed eGFP, demonstrating transduction. Alveolar macrophages showed increased PPARγ and ABCG1 expression after lenti-PPARγ instillation, whereas PPARγ and ABCG1 levels remained unchanged in lenti-eGFP controls. Alveolar macrophages from lenti-PPARγ-treated mice also exhibited reduced intracellular phospholipids and increased cholesterol efflux to HDL, an ABCG1-mediated pathway. In vivo instillation of lenti-PPARγ results in: 1) upregulating ABCG1 and PPARγ expression of GM-CSF KO alveolar macrophages, 2) reducing intracellular lipid accumulation, and 3) increasing cholesterol efflux activity.

Deletion of PPAR gamma in alveolar macrophages is associated with a Th-1 pulmonary inflammatory response.

Peroxisome proliferator-activated receptor gamma (PPARgamma) is constitutively expressed at high levels in healthy alveolar macrophages, in contrast to other tissue macrophages and blood monocytes. PPARgamma ligands have been shown to down-regulate IFN-gamma-stimulated inducible NO synthase (iNOS) in macrophages. Because NO is an important inflammatory mediator in the lung, we hypothesized that deletion of alveolar macrophage PPARgamma in vivo would result in up-regulation of iNOS and other inflammatory mediators. The loss of PPARgamma in macrophages was achieved by crossing floxed (+/+) PPARgamma mice and a transgenic mouse containing the CRE recombinase gene under the control of the murine M lysozyme promoter (PPARgammaKO). Alveolar macrophages were harvested by bronchoalveolar lavage (BAL). Lymphocytes (CD8:CD4 ratio = 2.8) were increased in BAL of PPARgammaKO vs wild-type C57BL6; p < or = 0.0001. Both iNOS and IFN-gamma expression were significantly elevated (p < or = 0.05) in BAL cells. Th-1 associated cytokines including IL-12 (p40), MIP-1alpha (CCL3), and IFN inducible protein-10 (IP-10, CXCL10) were also elevated. IL-4 and IL-17A were not detected. To test whether these alterations were due to the lack of PPARgamma, PPARgamma KO mice were intratracheally inoculated with a PPARgamma lentivirus construct. PPARgamma transduction resulted in significantly decreased iNOS and IFN-gamma mRNA expression, as well as reduced BAL lymphocytes. These results suggest that lack of PPARgamma in alveolar macrophages disrupts lung homeostasis and results in a Th1-like inflammatory response.

Targeted PPAR{gamma} deficiency in alveolar macrophages disrupts surfactant catabolism.

Surfactant accumulates in alveolar macrophages of granulocyte-macrophage colony-stimulating factor (GM-CSF) knockout (KO) mice and pulmonary alveolar proteinosis (PAP) patients with a functional loss of GM-CSF resulting from neutralizing anti-GM-CSF antibody. Alveolar macrophages from PAP patients and GM-CSF KO mice are de-ficient in peroxisome proliferator-activated receptor-gamma (PPARgamma) and ATP-binding cassette (ABC) lipid transporter ABCG1. Previous studies have demonstrated that GM-CSF induces PPARgamma. We therefore hypothesized that PPARgamma promotes surfactant catabolism through regulation of ABCG1. To address this hypothesis, macrophage-specific PPARgamma (MacPPARgamma) knockout mice were utilized. MacPPARgamma KO mice develop foamy, lipid-engorged Oil Red O positive alveolar macrophages. Lipid analyses revealed significant increases in the cholesterol and phospholipid contents of MacPPARgamma KO alveolar macrophages and extracellular bronchoalveolar lavage (BAL)-derived fluids. MacPPARgamma KO alveolar macrophages showed decreased expression of ABCG1 and a deficiency in ABCG1-mediated cholesterol efflux to HDL. Lipid metabolism may also be regulated by liver X receptor (LXR)-ABCA1 pathways. Interestingly, ABCA1 and LXRbeta expression were elevated, indicating that this pathway is not sufficient to prevent surfactant accumulation in alveolar macrophages. These results suggest that PPARgamma mediates a critical role in surfactant homeostasis through the regulation of ABCG1.

PPARgamma regulates the expression of cholesterol metabolism genes in alveolar macrophages.

Peroxisome proliferator-activated receptor-gamma (PPARgamma) is a nuclear transcription factor involved in lipid metabolism that is constitutively expressed in the alveolar macrophages of healthy individuals. PPARgamma has recently been implicated in the catabolism of surfactant by alveolar macrophages, specifically the cholesterol component of surfactant while the mechanism remains unclear. Studies from other tissue macrophages have shown that PPARgamma regulates cholesterol influx, efflux, and metabolism. PPARgamma promotes cholesterol efflux through the liver X receptor-alpha (LXRalpha) and ATP-binding cassette G1 (ABCG1). We have recently shown that macrophage-specific PPARgamma knockout (PPARgamma KO) mice accumulate cholesterol-laden alveolar macrophages that exhibit decreased expression of LXRalpha and ABCG1 and reduced cholesterol efflux. We hypothesized that in addition to the dysregulation of these cholesterol efflux genes, the expression of genes involved in cholesterol synthesis and influx was also dysregulated and that replacement of PPARgamma would restore regulation of these genes. To investigate this hypothesis, we have utilized a Lentivirus expression system (Lenti-PPARgamma) to restore PPARgamma expression in the alveolar macrophages of PPARgamma KO mice. Our results show that the alveolar macrophages of PPARgamma KO mice have decreased expression of key cholesterol synthesis genes and increased expression of cholesterol receptors CD36 and scavenger receptor A-I (SRA-I). The replacement of PPARgamma (1) induced transcription of LXRalpha and ABCG1; (2) corrected suppressed expression of cholesterol synthesis genes; and (3) enhanced the expression of scavenger receptors CD36. These results suggest that PPARgamma regulates cholesterol metabolism in alveolar macrophages.

Alveolar proteinosis syndrome: pathogenesis, diagnosis, and management.

PURPOSE OF REVIEW: This review discusses the most recent clinical and basic research literature on pulmonary alveolar proteinosis (PAP) as it relates to pathogenesis, diagnosis, and management. RECENT FINDINGS: The discovery of Granulocyte macrophage-colony stimulating factor (GM-CSF) and the alveolar macrophage as critical regulators of surfactant protein and lipid homeostasis has led to significant advances in PAP. Adults affected by PAP have circulating neutralizing anti-GM-CSF antibodies. Reduced localized GM-CSF activity in the lung (from neutralizing anti-GM-CSF antibodies), decreases alveolar macrophage surfactant degradation with surfactant excess and accumulation. Cause, source of antibodies or downstream effects of GM-CSF deficiency is speculative. GM-CSF antibodies above a threshold level have proved to be a useful diagnostic test. Research towards therapy has focused on improving the technique for therapeutic whole lung lavage as well as overcoming effects of neutralizing anti-GM-CSF, which include GM-CSF therapy (systemic and inhaled) and anecdotal reports of anti-B cell therapy. Whereas this approach has been somewhat successful for primary PAP, other causes of PAP (i.e. alveolar macrophage dysfunction, surfactant protein alterations) are still without therapy. SUMMARY: Understanding of the pathogenesis of PAP has greatly increased in the last decade; study has brought better comprehension of lung biology and recognition of the critical role for GM-CSF and alveolar macrophage in surfactant clearance. Balance between resident immune cell population and normal lung function still needs further study. Resident alveolar macrophages have an essential role in surfactant homeostasis. With this knowledge more effective diagnostic tests (e.g. anti-GM-CSF antibody) and therapies for PAP are under investigation.

Gene-environment interactions in sarcoidosis: challenge and opportunity.

Susceptibility to most human diseases is polygenic, with complex interactions between functional polymorphisms of single genes governing disease incidence, phenotype, or both. In this context, the contribution of any discrete gene is generally modest for a single individual, but may confer substantial attributable risk on a population level. Environmental exposure can modify the effects of a polymorphism, either by providing a necessary substrate for development of human disease or because the effects of a given exposure modulate the effects of the gene. In several diseases, genetic polymorphisms have been shown to be context dependent, ie, the effects of a genetic variant are realized only in the setting of a relevant exposure. Because sarcoidosis susceptibility is dependent on both genetic and environmental modifiers, the study of gene-environment interactions may yield important pathogenetic information and will likely be crucial for uncovering the range of genetic susceptibility loci. The complexity of these relationships implies, however, that investigations of gene-environment interactions will require the study of large cohorts with carefully defined exposures and similar clinical phenotypes. A general principle is that the study of gene-environment interactions requires a sample size at least severalfold greater than for either factor alone. To date, the presence of environmental modifiers has been demonstrated for one sarcoidosis susceptibility locus, HLA-DQB1, in African-American families. This article reviews general considerations obtaining for the study of gene-environment interactions in sarcoidosis. It also describes the limited current understanding of the role of environmental influences on sarcoidosis susceptibility genes.

Elevated gelatinase activity in pulmonary alveolar proteinosis: role of macrophage-colony stimulating factor.

Pulmonary alveolar proteinosis (PAP) is an anti-granulocyte macrophage-colony stimulating factor (GM-CSF) autoimmune disease resulting in the accumulation of phospholipids in the alveoli. GM-CSF knockout (KO) mice exhibit a strikingly similar lung pathology to patients with PAP. The lack of functionally active GM-CSF correlates with highly elevated concentrations of M-CSF in the lungs of PAP patients and GM-CSF KO mice. M-CSF has been associated with alternative macrophage activation, and in models of pulmonary fibrosis, M-CSF also contributes to tissue resorption and fibrosis. Matrix metalloproteinase-2 (MMP-2) and MMP-9 have been implicated in extracellular matrix degradation in animal models of fibrosis and asthma. We show for the first time that the lungs of PAP patients contain highly elevated levels of MMP-2 and MMP-9. PAP broncholaveolar lavage (BAL) cells but not bronchial epithelial cells expressed increased MMP-2 and MMP-9 mRNA relative to healthy controls. Both MMPs were detectable as pro and active proteins by gelatin zymography; and by fluorometric global assay, PAP-MMP activity was elevated. BAL cells/fluids from GM-CSF KO mice also demonstrated significantly elevated MMP-2 and MMP-9 gene expression, protein, and activity. Finally, PAP patients undergoing GM-CSF therapy exhibited significantly reduced MMPs and M-CSF. These data suggest that in the absence of GM-CSF, excess M-CSF in PAP may redirect alveolar macrophage activation, thus potentially contributing to elevated MMP expression in the lung.

An open-label trial of granulocyte macrophage colony stimulating factor therapy for moderate symptomatic pulmonary alveolar proteinosis.

Pulmonary alveolar proteinosis (PAP) is a rare idiopathic autoimmune lung disease in adults characterized by the accumulation of lipoproteinaceous material within the alveoli of the lung. The natural history of this disease is poorly defined. Current therapy of bilateral whole-lung lavage (WLL) under general anesthesia is invasive and has its limitations. Data suggest that relative granulocyte macrophage colony stimulating factor (GM-CSF) deficiency may be involved in the pathogenesis of this disease. There have been several case series that have described clinical improvement with exogenous GM-CSF therapy in a subset of patients with PAP. We describe the results of a prospective, open-label clinical trial of daily subcutaneous GM-CSF therapy in a group of adult patients with idiopathic PAP. In this series of 25 patients, the largest reported to date, administration of GM-CSF improved oxygenation as assessed by a 10 mm Hg decrease in alveolar-arterial oxygen gradient, as well as improvement in other clinical and quality of life parameters in 12 of 25 patients (48%) with moderate symptomatic disease who completed the trial. In addition, the serum anti-GM-CSF antibody titer correlated with lung disease activity and was a predictor for responsiveness to therapy. These data indicate that subcutaneous GM-CSF therapy is a promising alternative to WLL for symptomatic patients with PAP.

Comparison of sarcoidosis phenotypes among affected African-American siblings.

STUDY OBJECTIVE: To test the hypothesis that sibling pairs, who share genes and environmental exposures, might have similar phenotypic expressions of sarcoidosis beyond what would be expected by chance alone. DESIGN: Multicenter family study with study subjects recruited from 11 clinical centers. SUBJECTS: Subjects were African-American sibling pairs with sarcoidosis. Sarcoidosis and organ pattern involvement were defined according to specific criteria. Fifteen different organ systems were evaluated. RESULTS: For full-sibling pairs, ocular involvement was found in both siblings more often than expected by chance alone (p < 0.05), but the concordance was weak (kappa = 0.18). When analyzing full-sibling and half-sibling pairs, ocular and liver involvement showed a significant concordance between sibling pairs (p < 0.05), but again the agreement was poor (kappa = 0.16 for both). Concordance in pulmonary function change over time was also weak. Clinical outcomes of sibling pairs were not significantly correlated except for whether treatment was prescribed, and this level of agreement was poor (kappa = 0.14 for full-sibling and half-sibling pairs; kappa = 0.15 for full-sibling pairs only). Modeling phenotypic expression in sibling pairs using logistic regression did show that the presence of ocular and liver sarcoidosis in the first affected sibling conferred a statistically significant increased risk to the second affected sibling for having those organs involved (odds ratio [OR], 3; 95% confidence interval [CI], 1.7 to 5.4 for ocular; OR, 3.3; 95% CI, 1.5 to 7.4 for liver). CONCLUSIONS: The phenotypic features and clinical outcomes of sarcoidosis in sibling pairs show minimal concordance, with the possible exception that the presence of ocular or liver involvement in the first sibling with a diagnosis of sarcoidosis makes involvement of these organs more likely in other affected siblings.

Depressed peroxisome proliferator-activated receptor gamma (PPargamma) is indicative of severe pulmonary sarcoidosis: possible involvement of interferon gamma (IFN-gamma).

BACKGROUND AND AIM: Recent evidence suggests that the transcription factor, PPARgamma, is an important negative regulator of inflammation. Because studies of murine adipocytes and macrophages implicate IFN-gamma, a key mediator of granuloma formation in sarcoidosis, as a PPARgamma antagonist, we investigated the relationship between PPARgamma and IFN-gamma in bronchoalveolar lavage (BAL) cells of sarcoidosis patients and healthy controls. METHODS: BAL cells were analyzed for PPARgamma and IFN-gamma mRNA expression by quantitative PCR and for PPARgamma protein by immunocytochemistry and western blotting. RESULTS: In sarcoidosis patients with severe, treatment-requiring disease, IFN-gamma was strikingly elevated and PPARgamma gene expression was deficient. In contrast, PPARgamma expression of non-severe patients was comparable to control but was still accompanied by increased IFN-gamma. By confocal microscopy, nuclear PPARgamma protein was detectable in alveolar macrophages from non-severe patients unlike previous observations of severe patients. In vitro exposure of BAL cells or purified alveolar macrophages to IFN-gamma resulted in dose-dependent repression of PPARgamma mRNA in both sarcoidosis and controls. IFN-gamma treatment also reduced PPARgamma protein in BAL lysates and nuclear PPARgamma content in control alveolar macrophages, resulting in a diffuse cytoplasmic PPARgamma distribution similar to that observed in severe sarcoidosis. CONCLUSION: These novel results indicate that IFN-gamma represses PPARgamma in human alveolar macrophages but that in sarcoidosis, PPARgamma rather than IFN-gamma levels correlate best with disease severity. Data also emphasize the complex nature of PPARgamma restorative mechanisms in alveolar macrophages exposed to an inflammatory environment containing IFN-gamma -- a potential PPARgamma antagonist.

Estimating FVC from FEV2 and FEV3: assessment of a surrogate spirometric parameter.

BACKGROUND: In the context that accurate measurement of FVC is important in diagnosing airflow obstruction and in assessing restriction, strategies to achieve reliable and accurate FVC measurement have drawn much attention. OBJECTIVES: Because the rate of achieving end-of-test criteria during spirometry has been shown to be low, with resultant under-recording of the FVC, the current study proposes a regression equation for estimating FVC from measured values of the forced expiratory volume in 2 s (FEV2) and forced expiratory volume in 3 s (FEV3). METHODS: The predictive equation for the estimated FVC from volume measurements within the first 3 s of exhalation (estimated FVC3) was generated based on 330 consecutive acceptable spirograms performed in the Cleveland Clinic Foundation Pulmonary Function Laboratory. The equation was applied to an independent validation set comprised of spirometry measurements on 370 different consecutive patients. RESULTS: In the validation spirometry sample, in which the prevalence of obstruction was 34% (based on values of the measured FEV1/FVC compared to National Health and Nutrition Examination Survey III values), the sensitivity, specificity, and positive and negative predictive values of FEV1/estimated FVC3 for obstruction were 93.8%, 89.1%, 81.2%, and 96.9%, respectively. The misclassification rate was 9.2%. In the same cohort, the mean difference (+/- SD) between estimated FVC3 and measured FVC was 24.7 +/- 237 mL. CONCLUSIONS: Given that FVC is frequently under-recorded, with resultant overestimation of FEV1/FVC and underdiagnosis of airflow obstruction, we believe that estimating FVC from FEV2 and FEV3 can offer practical diagnostic advantages.

A sarcoidosis genetic linkage consortium: the sarcoidosis genetic analysis (SAGA) study.

BACKGROUND: Sarcoidosis, a systemic granulomatous disease of unknown etiology, likely results from an environmental insult in a genetically susceptible host. In the United States of America, African Americans have a higher sarcoidosis incidence and suffer greater morbidity than Caucasians. METHODS: A sarcoidosis genetic linkage study consortium was established to recruit African-American affected sib pair (ASP) families to identify chromosomal regions that may harbor sarcoidosis susceptibility genes and to determine if environmental factors modify any genetic effects. RESULTS: We successfully met our goal of enrolling 359 ASPs using a multifaceted recruitment approach. In the total 559 sib pairs that were enrolled, genetic analyses revealed incorrectly specified relationships that required reclassification or removal from the analysis dataset of 10.4% of reported full and 1.4% of reported half sib pairs. The final study sample comprised 415 full and 104 half sib pairs with complete data. This included 338 ASPs. Within sib pairs, affection status was not associated with sex. Only 15 per cent of the 229 families had three or more affected sibs, but they contributed 42 per cent of the ASP total. CONCLUSIONS: The SAGA study experience should provide useful lessons and information to serve others in conducting genetic studies of complex diseases in African-American families.