Anti-granulocyte Macrophage Colony-stimulating Factor Research Articles

Nocardia Infection in Patients With Anti-Granulocyte-Macrophage Colony-Stimulating Factor Autoantibodies: A Prospective Multicenter French Study.

Nocardiosis, a bacterial opportunistic infection caused by Nocardia spp, has recently been reported in patients with anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) autoantibodies, but insufficient data are available about disease presentation, outcomes, and occurrence of autoimmune pulmonary alveolar proteinosis (aPAP) in this population. We performed a prospective, multicenter, nationwide study in France and included patients with a Nocardia infection who had anti-GM-CSF autoantibodies. We describe their clinical, microbiological, and radiological characteristics, and their outcome at 1 year of follow-up. Twenty patients (18 [90%] male) were included, with a median age of 69 (interquartile range, 44-75) years. The organs most frequently involved were the brain (14/20 [70%]) and the lung (12/20 [60%]). Half of the infections were disseminated (10/20 [50%]). Nocardia identification was predominantly made in abscess fluid (17/20 [85%]), among which 10 (59%) were brain abscesses. The 1-year all-cause mortality was 5% (1/20), and only 1 case of aPAP (1/20 [5%]) occurred during the follow-up period. Nocardiosis with anti-GM-CSF autoantibodies is associated with a low mortality rate despite a high incidence of brain involvement. Although the occurrence of aPAP was infrequent during the 1-year follow-up period, long-term clinical data are needed to fully understand the potential relationship between nocardiosis, anti-GM-CSF autoantibodies, and aPAP.

Infections in autoimmune pulmonary alveolar proteinosis: a large retrospective cohort

BackgroundAutoimmune pulmonary alveolar proteinosis (aPAP) is a rare disease, predisposing to an increased risk of infection. A complete picture of these infections is lacking.Research questionDescribe the characteristics and clinical outcomes...

Anti-GM-CSF otilimab versus tofacitinib or placebo in patients with active rheumatoid arthritis and an inadequate response to conventional or biologic DMARDs: two phase 3 randomised trials (contRAst 1 and contRAst 2)

ObjectivesTo investigate the efficacy and safety of otilimab, an antigranulocyte-macrophage colony-stimulating factor antibody, in patients with active rheumatoid arthritis.MethodsTwo phase 3, double-blind randomised controlled trials including patients with inadequate responses...

P489 Anti-granulocyte-macrophage colony-stimulating factor (Anti-GM-CSF) autoantibodies—the underrecognized cause of Cryptococcosis in non-HIV individuals in Thailand: Case series from a single tertiary care hospital

Poster session 1, September 21, 2022, 12:30 PM - 1:30 PM BackgroundCryptococcosis is an opportunistic fungal infection in immunocompromised patients. Granulocyte-macrophage colony-stimulating factor (GM-CSF) regulates the functions of phagocytes and alveolar macrophages, which are crucial in cryptococcal control. Anti-granulocyte-macrophage colony-stimulating factor (Anti-GM-CSF) autoantibodies have been found to be associated with cryptococcosis in non-HIV individuals but this syndrome has never been described in Thai population.MethodsWe report here the case series of patients hospitalized in a tertiary care hospital in Northern Thailand.ResultsThree apparently immunocompetent patients, 34, 38, and 45 years old, were presented with neurological manifestations. Brain computed tomography scans and lumbar punctures were performed and the results showed evidence of cryptococcal meningoencephalitis. Two of the patients also had pulmonary cryptococcosis. We performed Anti-GM-CSF autoantibody ELISA assays in the patient's sera and all of three serum samples revealed a high titer of anti-GM-CSF autoantibodies. The patients were treated with amphotericin B deoxycholate with or without flucytosine for induction antifungal therapy, followed by fluconazole consolidation treatment. All patients were cured and had favorable outcomes.ConclusionsAnti-GM-CSF autoantibodies syndrome is underrecognized in Thai patients and is a new entity of immunodeficiency associated with cryptococcal meningoencephalitis and disseminated cryptococcosis in Thai patients.

Development of Pulmonary Alveolar Proteinosis in a Patient With Adult-Onset Still Disease Treated With Tocilizumab.

We report a patient with systemic adult-onset Still disease (AOSD) who developed anti-granulocyte-macrophage colony-stimulating factor (GM-CSF)-positive pulmonary alveolar proteinosis (PAP) while using tocilizumab (TCZ), diagnosed by milky white bronchoalveolar lavage fluid (BALF; Figure 1). To our knowledge, this is the first case of PAP in AOSD.

Neutralizing Anti-Granulocyte Macrophage-Colony Stimulating Factor Autoantibodies Recognize Post-Translational Glycosylations on Granulocyte Macrophage-Colony Stimulating Factor Years Before Diagnosis and Predict Complicated Crohn’s Disease

Anti-granulocyte macrophage-colony stimulating factor autoantibodies (aGMAbs) are detected in patients with ileal Crohn's disease (CD). Their induction and mode of action during or before disease are not well understood. We aimed to investigate the underlying mechanisms associated with aGMAb induction, from functional orientation to recognized epitopes, for their impact on intestinal immune homeostasis and use as a predictive biomarker for complicated CD. We characterized using enzyme-linked immunosorbent assay naturally occurring aGMAbs in longitudinal serum samples from patients archived before the diagnosis of CD (n= 220) as well as from 400 healthy individuals (matched controls) as part of the US Defense Medical Surveillance System. We used biochemical, cellular, and transcriptional analysis to uncover a mechanism that governs the impaired immune balance in CD mucosa after diagnosis. Neutralizing aGMAbs were found to be specific for post-translational glycosylation on granulocyte macrophage-colony stimulating factor (GM-CSF), detectable years before diagnosis, and associated with complicated CD at presentation. Glycosylation of GM-CSF was altered in patients with CD, and aGMAb affected myeloid homeostasis and promoted group 1 innate lymphoid cells. Perturbations in immune homeostasis preceded the diagnosis in the serum of patients with CD presenting with aGMAb and were detectable in the noninflamed CD mucosa. Anti-GMAbs predict the diagnosis of complicated CD long before the diagnosis of disease, recognize uniquely glycosylated epitopes, and impair myeloid cell and innate lymphoid cell balance associated with altered intestinal immune homeostasis.

Autoimmune pulmonary alveolar proteinosis exacerbated by steroid therapy due to misdiagnosis as anti-aminoacyl-tRNA synthetase (ARS) antibody positive- interstitial pneumonia: a case report

BackgroundAnti-aminoacyl-tRNA synthetase (anti-ARS) antibodies are myositis-specific autoantibodies that have been identified in a subset of patients with interstitial pneumonia who do not present with dermatomyositis or polymyositis. Anti-ARS antibody-positive interstitial pneumonia is commonly treated with steroids or immunosuppressive agents and is usually responsive to these therapies. Here, we present in detail a case in which respiratory failure of a patient diagnosed with anti-ARS antibody-positive interstitial pneumonia was exacerbated by treatment with steroids and immunosuppressive agents. Further examination revealed misdiagnosis of this patient and a subsequent diagnosis of autoimmune pulmonary alveolar proteinosis.Case presentationA 66-year-old man presented to the hospital with dyspnea on exertion, which resulted in the detection of interstitial pneumonia. Serum anti-ARS antibodies were detected; however, there were no other findings suggestive of myositis. Pulmonary alveolar proteinosis (PAP) was suspected based on the marked increase in serum KL-6 and chest computed tomography findings. The bronchoalveolar lavage revealed no milky changes in the lavage fluid. After treatment with steroids and initiation of immunosuppressive agents for anti-ARS antibody-positive interstitial pneumonia, respiratory failure and chest imaging findings showed worsening of the condition. Bronchoscopy was repeated, and milk-like alveolar lavage fluid was collected; serum anti-granulocyte macrophage colony-stimulating factor antibody was identified. Steroids and immunosuppressive agents were gradually tapered and discontinued, and the patient’s condition stabilized after repeated alveolar lavage under general anesthesia.ConclusionDue to similar presentation, PAP can be misdiagnosed as interstitial pneumonia. If pulmonary lesions due to interstitial pneumonia are exacerbated by immunosuppressive treatment, physicians should reconsider the diagnosis and include PAP in the differential diagnosis.

Anti-Granulocyte-Macrophage Colony-Stimulating Factor Monoclonal Antibody Gimsilumab for COVID-19 Pneumonia: A Randomized, Double-Blind, Placebo-controlled Trial.

Rationale: GM-CSF (granulocyte-macrophage colony-stimulating factor) has emerged as a promising target against the hyperactive host immune response associated with coronavirus disease (COVID-19). Objectives: We sought to investigate the efficacy and safety of gimsilumab, an anti-GM-CSF monoclonal antibody, for the treatment of hospitalized patients with elevated inflammatory markers and hypoxemia secondary to COVID-19. Methods: We conducted a 24-week randomized, double-blind, placebo-controlled trial, BREATHE (Better Respiratory Education and Treatment Help Empower), at 21 locations in the United States. Patients were randomized 1:1 to receive two doses of intravenous gimsilumab or placebo 1 week apart. The primary endpoint was all-cause mortality rate at Day 43. Key secondary outcomes were ventilator-free survival rate, ventilator-free days, and time to hospital discharge. Enrollment was halted early for futility based on an interim analysis. Measurements and Main Results: Of the planned 270 patients, 225 were randomized and dosed; 44.9% of patients were Hispanic or Latino. The gimsilumab and placebo groups experienced an all-cause mortality rate at Day 43 of 28.3% and 23.2%, respectively (adjusted difference = 5% vs. placebo; 95% confidence interval [-6 to 17]; P = 0.377). Overall mortality rates at 24 weeks were similar across the treatment arms. The key secondary endpoints demonstrated no significant differences between groups. Despite the high background use of corticosteroids and anticoagulants, adverse events were generally balanced between treatment groups. Conclusions: Gimsilumab did not improve mortality or other key clinical outcomes in patients with COVID-19 pneumonia and evidence of systemic inflammation. The utility of anti-GM-CSF therapy for COVID-19 remains unclear. Clinical trial registered with www.clinicaltrials.gov (NCT04351243).

Neutralizing Anti-Granulocyte-Macrophage Colony-Stimulating Factor Autoantibodies in Patients With Central Nervous System and Localized Cryptococcosis: Longitudinal Follow-up and Literature Review.

Neutralizing anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) autoantibodies (AAbs) have been increasingly recognized to predispose healthy individuals to disseminated cryptococcosis. However, studies have only considered patients with central nervous system (CNS) infection. No longitudinal study has captured the disease spectrum and clinical course. We prospectively enrolled adults without human immunodeficiency virus infection who had disseminated or unusual cryptococcosis. We compared the demographics, clinical features, kinetics of serum cryptococcal antigen (CrAg) titers, anti-GM-CSF AAb concentrations, and treatment outcomes between patients with (case patients) and without (control patients) anti-GM-CSF AAbs. Additional reports from the literature were also reviewed. Twenty-three patients were enrolled, of whom 6 tested positive for anti-GM-CSF AAbs. All case patients with positive fungal cultures (5/5 [100%]) were infected with Cryptococcus gattii VGII. Among them, 3 had exclusively pulmonary involvement, and 1 had only musculoskeletal lesions. Patients with CNS cryptococcosis exhibited a higher serum concentration of anti-GM-CSF AAbs than those with extraneural cryptococcosis. Case patients had higher initial and peak levels of serum CrAg and longer duration of antigenemia compared with the control patients. All case patients who had completed antifungal therapy had favorable outcomes without recurrence. Testing for anti-GM-CSF AAbs should be considered for not only previously healthy patients with disseminated cryptococcosis but also those with unexplained, localized cryptococcosis. Recurrence after completion of antifungal therapy was rare despite the persistence of anti-GM-CSF AAbs.

LB0001 MAVRILIMUMAB IMPROVES OUTCOMES IN PHASE 2 TRIAL IN NON-MECHANICALLY-VENTILATED PATIENTS WITH SEVERE COVID-19 PNEUMONIA AND SYSTEMIC HYPERINFLAMMATION

Background:Granulocyte/macrophage-colony stimulating factor (GM-CSF) is a cytokine both vital to lung homeostasis and important in regulating inflammation and autoimmunity1,2,3 that has been implicated in the pathogenesis of respiratory failure and death in patients with severe COVID-19 pneumonia and systemic hyperinflammation.4-6 Mavrilimumab is a human anti GM-CSF receptor α monoclonal antibody capable of blocking GM-CSF signaling and downregulating the inflammatory process.Objectives:To evaluate the effect of mavrilimumab on clinical outcomes in patients hospitalized with severe COVID-19 pneumonia and systemic hyperinflammation.Methods:This on-going, global, randomized, double-blind, placebo-controlled seamless transition Phase 2/3 trial was designed to evaluate the efficacy and safety of mavrilimumab in adults hospitalized with severe COVID-19 pneumonia and hyperinflammation. The Phase 2 portion comprised two groups: Cohort 1 patients requiring supplemental oxygen therapy without mechanical ventilation (to maintain SpO2 ≥92%) and Cohort 2 patients requiring mechanical ventilation, initiated ≤48 hours before randomization. Here, we report results for Phase 2, Cohort 1: 116 patients with severe COVID- 19 pneumonia and hyperinflammation from USA, Brazil, Chile, Peru, and South Africa; randomized 1:1:1 to receive a single intravenous administration of mavrilimumab (10 or 6 mg/kg) or placebo. The primary efficacy endpoint was proportion of patients alive and free of mechanical ventilation at Day 29. Secondary endpoints included [1] time to 2-point clinical improvement (National Institute of Allergy and Infectious Diseases COVID-19 ordinal scale), [2] time to return to room air, and [3] mortality, all measured through Day 29. The prespecified evidentiary standard was a 2-sided α of 0.2 (not adjusted for multiplicity).Results:Baseline demographics were balanced among the intervention groups; patients were racially diverse (43% non-white), had a mean age of 57 years, and 49% were obese (BMI ≥ 30). All patients received the local standard of care: 96% received corticosteroids (including dexamethasone) and 29% received remdesivir. No differences in outcomes were observed between the 10 mg/kg and 6 mg/kg mavrilimumab arms. Results for these groups are presented together. Mavrilimumab recipients had a reduced requirement for mechanical ventilation and improved survival: at day 29, the proportion of patients alive and free of mechanical ventilation was 12.3 percentage points higher with mavrilimumab (86.7% of patients) than placebo (74.4% of patients) (Primary endpoint; p=0.1224). Mavrilimumab recipients experienced a 65% reduction in the risk of mechanical ventilation or death through Day 29 (Hazard Ratio (HR) = 0.35; p=0.0175). Day 29 mortality was 12.5 percentage points lower in mavrilimumab recipients (8%) compared to placebo (20.5%) (p=0.0718). Mavrilimumab recipients had a 61% reduction in the risk of death through Day 29 (HR= 0.39; p=0.0726). Adverse events occurred less frequently in mavrilimumab recipients compared to placebo, including secondary infections and thrombotic events (known complications of COVID-19). Thrombotic events occurred only in the placebo arm (5/40 [12.5%]).Conclusion:In a global, diverse population of patients with severe COVID-19 pneumonia and hyperinflammation receiving supplemental oxygen therapy, corticosteroids, and remdesivir, a single infusion of mavrilimumab reduced progression to mechanical ventilation and improved survival. Results indicate mavrilimumab, a potent inhibitor of GM-CSF signaling, may have added clinical benefit on top of the current standard therapy for COVID-19. Of potential importance is that this treatment strategy is mechanistically independent of the specific virus or viral variant.

Efficacy, patient-reported outcomes, and safety of the anti-granulocyte macrophage colony-stimulating factor antibody otilimab (GSK3196165) in patients with rheumatoid arthritis: a randomised, phase 2b, dose-ranging study.

The human monoclonal antibody otilimab inhibits granulocyte-macrophage colony-stimulating factor (GM-CSF), a key driver in immune-mediated inflammatory conditions. We aimed to evaluate the efficacy, safety, and key patient-reported outcomes related to pain in patients with active rheumatoid arthritis receiving otilimab. This phase 2b, dose-ranging, multicentre, placebo-controlled study was done at 64 sites across 14 countries. Patients aged 18 years or older with rheumatoid arthritis who were receiving stable methotrexate were randomly assigned (1:1:1:1:1:1) to subcutaneous placebo or otilimab 22·5 mg, 45 mg, 90 mg, 135 mg, or 180 mg, plus methotrexate, once weekly for 5 weeks, then every other week until week 50. The randomisation schedule was generated by the sponsor, and patients were assigned to treatment by interactive response technology. Randomisation was blocked (block size of six) but was not stratified. Investigators, patients, and the sponsor were blinded to treatment. An unblinded administrator prepared and administered the study drug. The primary endpoint was the proportion of patients who achieved disease activity score for 28 joints with C-reactive protein (DAS28-CRP) <2·6 at week 24. Patients who were not in the otilimab 180 mg group, without a good or moderate European League Against Rheumatism response (week 12) or with DAS28-CRP >3·2 (week 24) escaped to otilimab 180 mg. Patients who escaped were treated as non-responders in their original assigned group. Safety endpoints were incidence of adverse events and serious adverse events, infections, and pulmonary events. Efficacy and safety outcomes were assessed in the intention-to-treat population. This study is registered with ClinicalTrials.gov, NCT02504671. Between July 23, 2015, and Dec 29, 2017, 222 patients were randomly assigned (37 to each group). 86 (49%) of 175 escaped to otilimab 180 mg at week 12 and 57 (69%) of 83 at week 24. At week 24, the proportion of patients with DAS28-CRP <2·6 was two (5%) of 37 in the otilimab 22·5 mg group, six (16%) of 37 in the 45 mg group, seven (19%) of 37 in the 90 mg group, five (14%) of 37 in the 135 mg group, five (14%) of 37 in the 180 mg, and one (3%) of 37 in the placebo group. The largest difference was achieved with otilimab 90 mg (16·2%; odds ratio [OR] 8·39, 95% CI 0·98-72·14; p=0·053). Adverse events were reported pre-escape in 19-24 (51-65%) patients and post escape in 10-17 (40-61%) patients across otilimab dose groups and in 18 (49%) of 37 and 22 (67%) of 33 in the placebo group. The most common adverse event was nasopharyngitis: 3-9 (8-24%) in otilimab groups and one (3%) in the placebo group pre-escape and 1-3 (4-10%) in otilimab groups and seven (21%) in the placebo group post escape. Pre-escape serious adverse events were foot fracture (otilimab 45 mg); arthralgia, myocardial infarction, dizziness (otilimab 90 mg); oesophageal spasm, acute pyelonephritis (otilimab 22·5 mg), and uterine leiomyoma (otilimab 135 mg). Post-escape serious adverse events were ankle fracture (placebo) and rheumatoid arthritis (otilimab 135 mg). There were no deaths or pulmonary events of clinical concern, and rates of serious infection were low. Otilimab plus methotrexate was well tolerated and, despite not achieving the primary endpoint of DAS28-CRP remission, there were improvements compared with placebo in disease activity scores. Of note, patients reported significant improvement in pain and physical function, supporting further clinical development of otilimab in rheumatoid arthritis. GlaxoSmithKline.

REFRACTORY SIROLIMUS-INDUCED PULMONARY ALVEOLAR PROTEINOSIS IN A PATIENT WITH LUNG TRANSPLANT

SESSION TITLE: Fellows Transplantation Posters SESSION TYPE: Fellow Case Report Posters PRESENTED ON: October 18-21, 2020 INTRODUCTION: Pulmonary alveolar proteinosis (PAP) is a rare disease with accumulation of proteins and lipids within the alveolar macrophages with considerable morbidity and mortality [1]. PAP etiologies include a primary autoimmune process due to anti-granulocyte macrophage colony stimulating factor (GM-CSF) antibodies while secondary causes include medications, infection, toxic inhalations, or hematological disorders [1]. Sirolimus, an immunosuppressant used in organ transplantation, is a rare cause of reversible PAP [2-6]. We present a patient who worsened despite discontinuation of sirolimus, regional lung lavage and inhaled GM-CSF. CASE PRESENTATION: A 57 year old female underwent bilateral lung transplant for idiopathic pulmonary fibrosis, complicated by acute rejection, bilateral pulmonary embolism, pulmonary artery stenosis requiring stenting, and bilateral airway anastomotic stenosis requiring a left mainstem stent. She presented with hypoxia five years post-transplant on sirolimus and prednisone. Chest CT demonstrated new unilateral ground glass opacities with bilateral septal thickening. Bronchoalveolar lavage (BAL) had milky fluid return, concerning for PAP. Sirolimus was discontinued and cyclosporine started. A segmental large volume BAL of the right upper lobe failed to improve hypoxia or shortness of breath and whole lung lavage was impractical due to bilateral anastomotic stenosis. She had resultant renal failure secondary to cyclosporine while off sirolimus for 3 months. Oxygen requirement and imaging failed to improve. Her anti-GM-CSF antibody test was negative and other causes of secondary PAP were ruled out. Salvage inhaled GM-CSF (sargramostim) was begun for progressive hypoxemic respiratory failure. VV-ECMO and whole lung lavage were offered but the patient declined. After four cycles of inhaled GM-CSF, her condition deteriorated and she passed away on POD 2492. Autopsy confirmed severe PAP. DISCUSSION: Sirolimus is a rare cause of secondary PAP. Typically sirolimus-induced PAP improves with medication discontinuation and potentially whole lung lavage. In this case, whole lung lavage was deemed impractical due to airway anatomy. She did not improve with sirolimus discontinuation or inhaled GM-CSF. Further research into the mechanism related to sirolimus induced PAP is necessary as this medication is widely used in complex patients with solid organ transplants. CONCLUSIONS: Sirolimus is implicated in drug induced PAP with expected reversibility when the medication is discontinued. This refractory case highlights the need for better understanding and treatment options in complex solid organ transplant patients. Reference #1: 1.Borie, R., et al., Pulmonary alveolar proteinosis. European Respiratory Review, 2011. 20(120): p. 98-107. 2.Mattewal, A.S., et al., Pulmonary alveolar proteinosis: a rare pulmonary toxicity of sirolimus in lung transplant patients. Chest, 2009. 136(4): p. 23S. 3.Pedroso, S.L., et al., Pulmonary alveolar proteinosis – a rare pulmonary toxicity of sirolimus. Transplant International, 2007. 20(3): p. 291-296. 4.Kadikoy, H., et al., Pulmonary alveolar proteinosis in a kidney transplant: a rare complication of sirolimus. Nephrology Dialysis Transplantation, 2010. 25(8): p. 2795-2798. 5.Garrean, S., et al., Sirolimus-associated interstitial pneumonitis in solid organ transplant recipients. Clinical transplantation, 2005. 19(5): p. 698-703. 6.Dhawan, K., A. Pope-Harman, and N. Sood, PULMONARY ALVEOLAR PROTEINOSIS SECONDARY TO SIROLIMUS IN A RENAL TRANSPLANT PATIENT. CHEST, 2009. 136(4): p. 34S. DISCLOSURES: No relevant relationships by Brian Boer, source=Web Response no disclosure on file for Heather Strah; No relevant relationships by Grant Turner, source=Web Response No relevant relationships by Navin Victor, source=Web Response

Pulmonary alveolar proteinosis: from classification to therapy.

Pulmonary alveolar proteinosis (PAP) is a rare respiratory syndrome characterised by the accumulation of surfactant lipoproteins within the alveoli. According to various pathogenetic mechanisms and aetiologies, PAP is classified as primary, secondary or congenital. Primary PAP is led by a granulocyte–macrophage colony-stimulating factor (GM-CSF) signalling disruption; the autoimmune form is driven by the presence of anti GM-CSF autoantibodies and represents 90% of all the PAP cases; and the hereditary form is the result of mutations in genes encoding GM-CSF receptor. Secondary PAP is associated with various diseases causing a reduction in function and/or number of alveolar macrophages. Congenital PAP emerges as a consequence of corrupted surfactant production, due to mutations in surfactant proteins or lipid transporter, or mutations affecting lung development. The clinical manifestations are various, ranging from insidious onset to acute or progressive respiratory failure, including premature death within the first days of life in neonates with congenital surfactant production disorders. The diagnostic workup includes clinical and radiological assessment (respiratory function test, high-resolution chest computed tomography), laboratory tests (anti-GM-CSF autoantibodies dosage, GM-CSF serum level and GM-CSF signalling test), and genetic tests. Whole-lung lavage is the current gold standard of care of PAP; however, the therapeutic approach depends on the pathogenic form and disease severity, including GM-CSF augmentation strategies in autoimmune PAP and other promising new treatments.Educational aimsTo update knowledge about a rare respiratory syndrome, pulmonary alveolar proteinosis, in order to promote early diagnosis and correct management.To highlight recent treatment options based on pathogenesis and disease severity.

534: Anti-granulocyte macrophage-colony stimulating factor (GM-CSF) antibody prevents the upregulation of cyclooxygenase-2 in a mouse model

Preterm birth is believed to be a final common pathway of a multitude of instigating factors, and inflammation plays a critical role in preterm birth. Previous work from our laboratory has shown granulocyte macrophage-colony-stimulating factor (GM-CSF), a pro-inflammatory cytokine, is upregulated in the uterus in a mouse model of preterm birth. We have also shown treatment with an antibody to GM-CSF will prevent preterm birth within six hours. Therefore, we hypothesized treatment with an antibody to GM-CSF will prevent the upregulation of contraction associated proteins in the uterus leading to preterm birth. For this study, we utilized a mouse model of preterm birth. On embryonic day 17, pregnant CD1 mice were anesthetized and received an intrauterine injection of lipopolysaccharide (LPS) along with either an intravenous injection of anti-mouse GM-CSF or control antibody. After six hours the uteri were harvested and analyzed for expression of the oxytocin transmembrane receptor (OXTR), cyclooxygenase-2 (COX-2), or connexin-43 (Cx43) using quantitative polymerase chain reaction (qPCR). LPS increased the expression of COX-2 (p<0.001) compared to mice receiving an intrauterine injection of saline, and treatment with the anti-mouse GM-CSF antibody resulted in a decreased expression of COX-2 (p<0.05). Treatment with LPS did not increase the expression of OXTR or Cx43 compared to control mice, although the GM-CSF antibody did decrease the expression of Cx43 compared to mice treated with the control antibody. These studies demonstrate treatment with the anti-mouse GM-CSF antibody prevents upregulation of the contraction associated protein COX-2 in the uterus utilizing an inflammatory mouse model. Further research is needed to determine if antibodies to GM-CSF can be utilized as a therapeutic agent to prevent preterm birth.

PULMONARY ALVEOLAR PROTEINOSIS PRESENTING AS INTRACEREBRAL NOCARDIOSIS

SESSION TITLE: Diffuse Lung Disease SESSION TYPE: Med Student/Res Case Report PRESENTED ON: 10/09/2018 07:30 am - 08:30 am INTRODUCTION: Pulmonary alveolar proteinosis (PAP) is a rare disorder with an incidence of 0.5 / million people [1]. PAP is caused by the accumulation of surfactant in the alveoli, leading to hypoxemic respiratory failure and increased risk of opportunistic infections [2]. First-line therapy after infection eradication is whole-lung lavage. Treatment with exogenous granulocyte macrophage colony stimulating factor (GM-CSF) is under investigation. PAP can be a diagnostic challenge due to its low prevalence and nonspecific presentation. Here we describe a unique presentation that was diagnosed as PAP. CASE PRESENTATION: A 56 year old male farmer, never smoker, with no past medical history presented with right-sided weakness, two months of dyspnea, and dry cough. Brain MRI demonstrated multiple cerebral rim-enhancing abscesses (Fig 1A). He underwent a craniotomy and evacuation of cerebral abscesses with acid fast cultures positive for Nocardia farcinica. Chest CT showed a "crazy paving" pattern consistent with PAP (Fig 1B, C). Serum anti GM-CSF antibody was positive. Bronchoscopy showed opaque fluid on bronchoalveolar lavage, with negative cultures, and clumps of amorphous proteinaceous material consistent with PAP. Disseminated Nocardia was treated with ciprofloxacin for 1 year and sulfamethoxazole/ trimethoprim for 6 months. He underwent a whole lung lavage with resolution of symptoms. DISCUSSION: PAP is caused by surfactant accumulation due to incomplete removal by alveolar macrophages. Autoimmune PAP (primary PAP) accounts for the majority of cases [1]. Autoimmune PAP is caused by anti GM-CSF antibodies that disrupt macrophage activation, antigen presentation, and phagocytosis [2]. Secondary PAP is thought due to a relative deficiency of GM-CSF usually in the setting of hematologic diseases or dust exposures. The ensuing macrophage dysfunction leads to increased infection risk. Opportunistic infections including Nocardia, Mycobacterium, and fungi in otherwise immunocompetent patients with PAP have been previously reported [2]. In a report of 7 patients with disseminated Nocardiosis without PAP, 5 patients were found to have anti GM-CSF antibodies; two of these patients were also found to have radiographic characteristics of PAP [3]. CONCLUSIONS: Primary PAP is a rare autoimmune disorder that confers an immunocompromised state due to impaired alveolar macrophage activation. Opportunistic infections such as Nocardiosis are frequently seen with PAP. Eradication of the opportunistic infections, and targeted whole lung lavage are effective at relieving hypoxia in PAP. A high diagnostic suspicion is essential in the work-up of PAP. Reference #1: Clinics in Chest Medicine. 2016;37(3):431-440. https://doi.org/10.1016/j.ccm.2016.04.006 Reference #2: Journal of Infectio. 2012;65(2):173-179. https://doi.org/10.1016/j.jinf.2012.03.020 Reference #3: Clinical Infectious Disease. 2014;60(7):1017-1025. https://doi.org/10.1093/cid/ciu968 DISCLOSURES: No relevant relationships by David Dennis, source=Web Response No relevant relationships by Ulysses Magalang, source=Web Response No relevant relationships by Virgil Secasanu, source=Web Response

Secondary pulmonary alveolar proteinosis: a single-center retrospective study (a case series and literature review)

BackgroundSecondary pulmonary alveolar proteinosis (sPAP) is an extremely rare disease. The clinical features of sPAP patients remain to be summarizeds. MethodsPatients pathologically diagnosed with PAP and with negative results for anti-granulocyte macrophage colony stimulating factor (GM-CSF) autoantibodies from Peking Union Medical College Hospital between January 2000 and July 2016 were retrospectively studied. The PubMed database was also searched for literature to collect published cases.ResultsIn our center, nine patients were diagnosed as sPAP with a median age of 37 years. Hematological disorders, including myelodysplastic syndrome (MDS), chronic myelogenous leukemia (CML), and pulmonary tuberculosis (TB) infection were the underlying diseases. Cases secondary to MDS had very poor prognosis as all of them survived less than 2 years after their diagnosis, while those secondary to TB had favorable prognosis. Only 33.3% of cases showed interlobular septal thickening in our sPAP group. Through literature review, 164 sPAP cases were collected. The age at diagnosis was 45.0 ± 14.8 years old and the gender radio was 1.20:1 (M:F). 61.9% of cases were diagnosed by bronchoscopy. MDS and CML were common underlying diseases in 34.1% and 15.2% of patients, respectively. Patients with sPAP secondary to hematological diseases had a short survival time and half of them died within 14.95 months after diagnosis.ConclusionsMDS and TB infection were the most frequent underlying causes of sPAP in this single-center research in China, with cases secondary to MDS having a poor survival rate. sPAP was more likely to be secondary to hematological disorders, especially MDS and CML and had a fairly poor prognosis in published cases. sPAP should be suspected in PAP patients whose CT scan presents only ground-glass opacities without interlobular septal thickening.

The infarcted myocardium solicits GM-CSF for the detrimental oversupply of inflammatory leukocytes.

Myocardial infarction (MI) elicits massive inflammatory leukocyte recruitment to the heart. Here, we hypothesized that excessive leukocyte invasion leads to heart failure and death during acute myocardial ischemia. We found that shortly and transiently after onset of ischemia, human and mouse cardiac fibroblasts produce granulocyte/macrophage colony-stimulating factor (GM-CSF) that acts locally and distally to generate and recruit inflammatory and proteolytic cells. In the heart, fibroblast-derived GM-CSF alerts its neighboring myeloid cells to attract neutrophils and monocytes. The growth factor also reaches the bone marrow, where it stimulates a distinct myeloid-biased progenitor subset. Consequently, hearts of mice deficient in either GM-CSF or its receptor recruit fewer leukocytes and function relatively well, whereas mice producing GM-CSF can succumb from left ventricular rupture, a complication mitigated by anti-GM-CSF therapy. These results identify GM-CSF as both a key contributor to the pathogenesis of MI and a potential therapeutic target, bolstering the idea that GM-CSF is a major orchestrator of the leukocyte supply chain during inflammation.

Phase 2, randomised placebo-controlled trial to evaluate the efficacy and safety of an anti-GM-CSF antibody (KB003) in patients with inadequately controlled asthma

ObjectivesWe wished to evaluate the effects of an antigranulocyte-macrophage colony-stimulating factor monoclonal antibody (KB003) on forced expiratory volume in 1 s (FEV1), asthma control and asthma exacerbations in adult asthmatics...

Characteristics of serum lipid metabolism in patients with autoimmune pulmonary alveolar proteinosis.

To study the serum lipid panels in consecutive autoimmune pulmonary alveolar proteinosis(APAP)patients and analyze their relationship with anti-granulocyte macrophage-colony stimulating factor(GM-CSF)antibody and other markers. Thirty-two non-diabetic APAP patients were enrolled in the study. Serum lipids of these patients and 100 healthy volunteers were tested after an overnight fasting. Anti-GM-CSF antibody levels were measured with enzyme-linked immunosorbent assay. The correlation of serum lipids with lactate dehydrogenase,carcinoembryonic antigen,pulmonary function,and artery blood gas parameters were analyzed. Total cholesterol and low-density lipoprotein cholesterol levels [(5.54±0.99)and(3.73±0.83)mmol/L respectively] were significantly higher in APAP patients than in healthy volunteers [(5.05±0.97)and(3.17±0.89)mmol/L respectively](all P<0.05). High-density lipoprotein cholesterol(HDL-C)level of the APAP group [(1.10±0.18)mmol/L ]was significantly lower than that of the healthy group(P<0.05). Low-density lipoprotein/HDL and total cholesterol/HDL ratios in the APAP group(3.47±0.90 and 5.14±1.12 respectively)were significantly higher than those in the healthy group[(2.63±0.87)and(4.18±1.12)](all P<0.05). There was no significant difference in triglyceride level between the two groups(P>0.05). HDL-C level was negatively correlated with alveolar-arterial oxygen pressure difference(r=-0.436,P<0.05)and positively correlated with arterial oxygen saturation(r=0.459,P<0.05). None of the lipid markers correlated with serum anti-GM-CSF antibody levels(all P>0.05). APAP patients were likely to suffer from disturbed lipid metabolism,which was correlated with disease severity to some degree. Lipid markers deserved more attention in the management of APAP patients.

P0053 Expression of the GM-CSF gene and anti GM-CSF antibodies in egyptian adults with acute myeloid leukaemia and myelodysblastic syndromes

<h3>Background</h3> Granulocyte–macrophage colony stimulating factor (GM-CSF) is a pleiotropic cytokine, which regulates myeloid progenitors. Antibodies to GM-CSF, while uncommon, are implicated in the pathogenesis of some diseases. We aimed to assess GM-CSF mRNA gene expression and anti GM-CSF antibodies in acute myeloid leukaemia (AML) and myelodysblastic syndromes (MDS) in relation to disease behaviour, patients' survival, and therapy outcome. <h3>Methods</h3> We examined GM-CSF mRNA gene expression quantitatively by real time PCR (RT-PCR) and anti GM-CSF antibodies by ELISA in sera of 50 AML/MDS Egyptian cases in comparison with 20 healthy blood donors (HD). <h3>Findings</h3> We found lower GM-CSF gene expression (<i>p</i>=0.008) and higher serum levels of anti GM-CSF antibodies (<i>p</i>=0.001) in cases irrespective of disease category when compared to HD. <h3>Interpretation</h3> Alteration in GM-CSF gene expression is implicated in the pathogenesis of AML/MDS and also the high titre of anti GM-CSF antibodies might influence myeloid development. Use of anti GM-CSF for disease monitoring and as a marker of disease activity needs larger future studies.