The Renin-Angiotensin-Aldosterone System Regulates Sarcoidosis Granulomatous Inflammation.

Rationale: Sarcoidosis is a granulomatous disorder of unclear cause notable for abnormal elevation of blood and tissue angiotensin converting enzyme 1 (ACE1) levels and activity. ACE1 regulates the renin-angiotensin-aldosterone system (RAAS), the terminal product of which is aldosterone, which selectively engages mineralocorticoid receptors (MR) to promote inflammation. Objectives: We sought to determine whether the RAAS promotes sarcoidosis granuloma formation and related inflammatory responses. Methods: Using an established ex vivo model, we first determined whether aldosterone was produced by sarcoidosis granulomas and verified the presence of CYP11B2, the enzyme required for its production. We then evaluated the effects of selective inhibitors of ACE1 (captopril), angiotensin type 1 receptor (losartan) and MR (spironolactone, eplerenone) on granuloma formation, reflected by computer image analysis-generated granuloma area, and selected cytokines incriminated in sarcoidosis pathogenesis. Measurements and Main Results: Aldosterone was spontaneously produced by sarcoidosis PBMCs, and both intra- and extracellular levels steadily increased during granuloma formation. In parallel, PBMCs were shown to express more CYP11B2 during granuloma formation. Significant inhibition of sarcoidosis granulomas and related cytokines (TNFα, IL-1ß, IFNγ, IL-10) was observed in response to pretreatments with captopril, losartan, spironolactone or eplerenone, comparable to that of prednisone. Conclusions: The RAAS is intact in sarcoidosis granulomas and contributes significantly to early granuloma formation and to related inflammatory mediator responses with important implications for clinical management.

Investigating cryopreserved PBMC functionality in an antigen-induced model of sarcoidosis granuloma formation.

Sarcoidosis, a systemic inflammatory disease, poses challenges in understanding its etiology and variable clinical courses. Despite ongoing uncertainty about causative agents and genetic predisposition, granuloma formation remains its hallmark feature. To address this, we developed a validated in vitro human granuloma model using patient-derived peripheral blood mononuclear cells (PBMCs), offering a dynamic platform for studying early granuloma formation and sarcoidosis pathogenesis. However, a current limitation of this model is its dependence on freshly isolated PBMCs obtained from whole blood. While cryopreservation is a common method for long-term sample preservation, the biological effects of freezing and thawing PBMCs on granuloma formation remain unclear. This study aimed to assess the viability and functionality of cryopreserved sarcoidosis PBMCs within the granuloma model, revealing similar granulomatous responses to fresh cells and highlighting the potential of cryopreserved PBMCs as a valuable tool for studying sarcoidosis and related diseases.

Leveraging in vitro and pharmacokinetic models to support bench to bedside investigation of XTMAB-16 as a novel pulmonary sarcoidosis treatment.

Background: Sarcoidosis is a chronic, multisystem inflammatory disorder characterized by non-caseating epithelioid granulomas; infiltration of mononuclear cells; and destruction of microarchitecture in the skin, eye, heart, and central nervous system, and the lung in >90% of cases. XTMAB-16 is a chimeric anti-tumor necrosis factor alpha (TNFα) antibody, distinct from other anti-TNF antibodies based on its molecular structure. The efficacy of XTMAB-16 has not been clinically demonstrated, and it is still undergoing clinical development as a potential treatment for sarcoidosis. The current study demonstrates the activity of XTMAB-16 in a well-established in vitro sarcoidosis granuloma model, although XTMAB-16 is not yet approved by the United States Food and Drug Administration (FDA) for treatment of sarcoidosis, or any other disease. Objective: To provide data to guide safe and efficacious dose selection for the ongoing clinical development of XTMAB-16 as a potential treatment for sarcoidosis. Methods: First, XTMAB-16 activity was evaluated in an established in vitro model of granuloma formation using peripheral blood mononuclear cells from patients with active pulmonary sarcoidosis to determine a potentially efficacious dose range. Second, data obtained from the first-in-human study of XTMAB-16 (NCT04971395) were used to develop a population pharmacokinetic (PPK) model to characterize the pharmacokinetics (PK) of XTMAB-16. Model simulations were performed to evaluate the sources of PK variability and to predict interstitial lung exposure based on concentrations in the in vitro granuloma model. Results: XTMAB-16 dose levels of 2 and 4 mg/kg, once every 2 weeks (Q2W) or once every 4 weeks (Q4W) for up to 12 weeks, were supported by data from the non-clinical, in vitro secondary pharmacology; the Phase 1 clinical study; and the PPK model developed to guide dose level and frequency assumptions. XTMAB-16 inhibited granuloma formation and suppressed interleukin-1ß (IL-1ß) secretion in the in vitro granuloma model with a half maximal inhibitory concentration (IC50) of 5.2 and 3.5 µg/mL, respectively. Interstitial lung concentrations on average, following 2 or 4 mg/kg administered Q2W or Q4W, are anticipated to exceed the in vitro IC50 concentrations. Conclusion: The data presented in this report provide a rationale for dose selection and support the continued clinical development of XTMAB-16 for patients with pulmonary sarcoidosis.

The influence of age and sex in sarcoidosis.

PURPOSE OF REVIEW: This review aims to describe how the clinical manifestations of sarcoidosis may be shaped by the effects of sex hormones and by age dependent changes in immune functions and physiology This review is intended to highlight the need to consider the effects of sex and sex in future studies of sarcoidosis. RECENT FINDINGS: The clinical manifestations of sarcoidosis differ based on sex and gender There is emerging evidence that female and male hormones and X-linked genes are important determinants of immune responses to environmental antigens, which has important implications for granuloma formation in the context of sarcoidosis Furthermore, sex hormone levels predictably change throughout adolescence and adulthood, and this occurs in parallel with the onset immune senescence and changes in physiology with advanced age. SUMMARY: Recent studies indicate that sex and age are important variables shaping the immune response of humans to environmental antigens We posit herein that sex and age are important determinants of sarcoidosis clinical phenotypes Many gaps in our understanding of the roles played by sex and gender in sarcoidosis, and these need to be considered in future studies.

The landscape of transcriptomic and proteomic studies in sarcoidosis.

Multiple overlapping pathways are identified in tissue, BAL cells, PBMCs and a sarcoidosis in vitro granuloma model. Inferences from omic studies are constrained by small sample sizes. Studies comparing differences between sarcoidosis phenotypes are needed. https://bit.ly/30NaHz4.

A Pilot Randomized Trial of Transdermal Nicotine for Pulmonary Sarcoidosis.

BACKGROUND: Tobacco smoking is associated with a reduced risk of developing sarcoidosis, and we previously reported that nicotine normalizes immune responses to environmental antigens in patients with active pulmonary sarcoidosis. The effects of nicotine on the progression of pulmonary sarcoidosis are unknown. RESEARCH QUESTION: Is nicotine treatment well tolerated, and will it improve lung function in patients with active pulmonary sarcoidosis? STUDY DESIGN AND METHODS: With local institutional review board approval, a randomized, double-blind, controlled pilot trial was conducted of daily nicotine transdermal patch treatment (21 mg daily) or placebo patch use for 24 weeks. The Ohio State University Wexner Medical Center and Cleveland Clinic enrolled 50 consecutive subjects aged ≥ 18 years with active pulmonary sarcoidosis, based on symptoms (ie, dyspnea, cough) and objective radiographic evidence of infiltrates consistent with nonfibrotic lung disease. Each study group was compared at 26 weeks based on repeated measures of FVC, FEV1, quantitative lung texture score based on CT texture analysis, Fatigue Assessment Score (FAS), St. George's Respiratory Questionnaire (SGRQ), and the Sarcoidosis Assessment Tool. RESULTS: Nicotine treatment was associated with a clinically significant, approximately 2.1% (70 mL) improvement in FVC from baseline to 26 weeks. FVC decreased by a similar amount (2.2%) in the placebo group, with a net increase of 140 mL (95% CI, 10-260) when comparing nicotine vs placebo groups at 26 weeks. FEV1 and FAS improved marginally in the nicotine-treated group, compared with those on placebo. No improvement was observed in lung texture score, FAS, St. George's Respiratory Questionnaire score, or the Sarcoidosis Assessment Tool. There were no reported serious adverse events or evidence of nicotine addiction. INTERPRETATION: Nicotine treatment was well tolerated in patients with active pulmonary sarcoidosis, and the preliminary findings of this pilot study suggest that it may reduce disease progression, based on FVC. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov; No.: NCT02265874; URL: www.clinicaltrials.gov.

Phagosome-regulated mTOR signalling during sarcoidosis granuloma biogenesis.

INTRODUCTION: Sarcoidosis and tuberculosis are granulomatous pulmonary diseases characterised by heightened immune reactivity to Mycobacterium tuberculosis antigens. We hypothesised that an unsupervised analysis comparing the molecular characteristics of granulomas formed in response to M. tuberculosis antigens in patients with sarcoidosis or latent tuberculosis infection (LTBI) would provide novel insights into the pathogenesis of sarcoidosis. METHODS: A genomic analysis identified differentially expressed genes in granuloma-like cell aggregates formed by sarcoidosis (n=12) or LTBI patients (n=5) in an established in vitro human granuloma model wherein peripheral blood mononuclear cells were exposed to M. tuberculosis antigens (beads coated with purified protein derivative) and cultured for 7 days. Pathway analysis of differentially expressed genes identified canonical pathways, most notably antigen processing and presentation via phagolysosomes, as a prominent pathway in sarcoidosis granuloma formation. The phagolysosomal pathway promoted mechanistic target of rapamycin complex 1 (mTORc1)/STAT3 signal transduction. Thus, granuloma formation and related immune mediators were evaluated in the absence or presence of various pre-treatments known to prevent phagolysosome formation (chloroquine) or phagosome acidification (bafilomycin A1) or directly inhibit mTORc1 activation (rapamycin). RESULTS: In keeping with genomic analyses indicating enhanced phagolysosomal activation and predicted mTORc1 signalling, it was determined that sarcoidosis granuloma formation and related inflammatory mediator release was dependent upon phagolysosome assembly and acidification and mTORc1/S6/STAT3 signal transduction. CONCLUSIONS: Sarcoidosis granulomas exhibit enhanced and sustained intracellular antigen processing and presentation capacities, and related phagolysosome assembly and acidification are required to support mTORc1 signalling to promote sarcoidosis granuloma formation.

Differential transcriptomics in sarcoidosis lung and lymph node granulomas with comparisons to pathogen-specific granulomas.

RATIONALE: Despite the availability of multi-"omics" strategies, insights into the etiology and pathogenesis of sarcoidosis have been elusive. This is partly due to the lack of reliable preclinical models and a paucity of validated biomarkers. As granulomas are a key feature of sarcoidosis, we speculate that direct genomic interrogation of sarcoid tissues, may lead to identification of dysregulated gene pathways or biomarker signatures. OBJECTIVE: To facilitate the development sarcoidosis genomic biomarkers by gene expression profiling of sarcoidosis granulomas in lung and lymph node tissues (most commonly affected organs) and comparison to infectious granulomas (coccidiodomycosis and tuberculosis). METHODS: Transcriptomic profiles of immune-related gene from micro-dissected sarcoidosis granulomas within lung and mediastinal lymph node tissues and compared to infectious granulomas from paraffin-embedded blocks. Differentially-expressed genes (DEGs) were profiled, compared among the three granulomatous diseases and analyzed for functional enrichment pathways. RESULTS: Despite histologic similarities, DEGs and pathway enrichment markedly differed in sarcoidosis granulomas from lymph nodes and lung. Lymph nodes showed a clear immunological response, whereas a structural regenerative response was observed in lung. Sarcoidosis granuloma gene expression data corroborated previously reported genomic biomarkers (STAB1, HBEGF, and NOTCH4), excluded others and identified new genomic markers present in lung and lymph nodes, ADAMTS1, NPR1 and CXCL2. Comparisons between sarcoidosis and pathogen granulomas identified pathway divergences and commonalities at gene expression level. CONCLUSION: These findings suggest the importance of tissue and disease-specificity evaluation when exploring sarcoidosis genomic markers. This relevant translational information in sarcoidosis and other two histopathological similar infections provides meaningful specific genomic-derived biomarkers for sarcoidosis diagnosis and prognosis.

Design, rationale, and baseline characteristics of a pilot randomized clinical trial of nicotine treatment for pulmonary sarcoidosis.

INTRODUCTION: Sarcoidosis is a systemic granulomatous disease of unknown cause afflicting young to middle-aged adults. The majority of patients with active pulmonary sarcoidosis complain of overwhelming fatigue, which often persists despite administration of immune-modulating drugs typically used to treat sarcoidosis. Nicotine offers an alternative to conventional treatments, which are associated with a spectrum of serious untoward effects, including diabetes mellitus, osteoporosis, bone marrow suppression, severe infections, cirrhosis. The described pilot randomized trial aims to provide preliminary data required to design subsequent Phase II/III trials to formally evaluate nicotine as a novel low-cost and highly-effective, safe treatment option for patients with active pulmonary sarcoidosis. METHODS: and Design: This is a randomized double-blind controlled trial of adults with confirmed pulmonary sarcoidosis, allocated in equal proportion to sustained release transdermal nicotine or placebo patch. The primary objective outcome is the improvement in forced vital capacity at study week 26 from baseline measurement. Secondary measures include lung texture score, and self-reported outcomes including the Fatigue Assessment Scale, the St George's Respiratory Questionnaire, and the Sarcoidosis Assessment Tool. DISCUSSION: Current therapies for active pulmonary sarcoidosis, remain either expensive and often with numerous side-effects, as with novel industry developed therapies, or with reduced quality of life, as with corticosteroids. Nicotine therapy provides promise as a safe, available, and cost-effective intervention strategy, which we expect to be acceptable to patients. CLINICALTRIALSGOV: NCT02265874.

Current Sarcoidosis Models and the Importance of Focusing on the Granuloma.

The inability to effectively model sarcoidosis in the laboratory or in animals continues to hinder the discovery and translation of new, targeted treatments. The granuloma is the signature pathological hallmark of sarcoidosis, yet there are significant knowledge gaps that exist with regard to how granulomas form. Significant progress toward improved therapeutic and prognostic strategies in sarcoidosis hinges on tractable experimental models that recapitulate the process of granuloma formation in sarcoidosis and allow for mechanistic insights into the molecular events involved. Through its inherent representation of the complex genetics underpinning immune cell dysregulation in sarcoidosis, a recently developed in vitro human granuloma model holds promise in providing detailed mechanistic insight into sarcoidosis-specific disease regulating pathways at play during early stages of granuloma formation. The purpose of this review is to critically evaluate current sarcoidosis models and assess their potential to progress the field toward the goal of improved therapies in this disease. We conclude with the potential integrated use of preclinical models to accelerate progress toward identifying and testing new drugs and drug combinations that can be rapidly brought to clinical trials.

Diagnosis and Detection of Sarcoidosis. An Official American Thoracic Society Clinical Practice Guideline.

Background: The diagnosis of sarcoidosis is not standardized but is based on three major criteria: a compatible clinical presentation, finding nonnecrotizing granulomatous inflammation in one or more tissue samples, and the exclusion of alternative causes of granulomatous disease. There are no universally accepted measures to determine if each diagnostic criterion has been satisfied; therefore, the diagnosis of sarcoidosis is never fully secure.Methods: Systematic reviews and, when appropriate, meta-analyses were performed to summarize the best available evidence. The evidence was appraised using the Grading of Recommendations, Assessment, Development, and Evaluation approach and then discussed by a multidisciplinary panel. Recommendations for or against various diagnostic tests were formulated and graded after the expert panel weighed desirable and undesirable consequences, certainty of estimates, feasibility, and acceptability.Results: The clinical presentation, histopathology, and exclusion of alternative diagnoses were summarized. On the basis of the available evidence, the expert committee made 1 strong recommendation for baseline serum calcium testing, 13 conditional recommendations, and 1 best practice statement. All evidence was very low quality.Conclusions: The panel used systematic reviews of the evidence to inform clinical recommendations in favor of or against various diagnostic tests in patients with suspected or known sarcoidosis. The evidence and recommendations should be revisited as new evidence becomes available.

Delphi consensus recommendations for a treatment algorithm in pulmonary sarcoidosis.

Pulmonary sarcoidosis presents substantial management challenges, with limited evidence on effective therapies and phenotypes. In the absence of definitive evidence, expert consensus can supply clinically useful guidance in medicine. An international panel of 26 experts participated in a Delphi process to identify consensus on pharmacological management in sarcoidosis with the development of preliminary recommendations.The modified Delphi process used three rounds. The first round focused on qualitative data collection with open-ended questions to ensure comprehensive inclusion of expert concepts. Rounds 2 and 3 applied quantitative assessments using an 11-point Likert scale to identify consensus.Key consensus points included glucocorticoids as initial therapy for most patients, with non-biologics (immunomodulators), usually methotrexate, considered in severe or extrapulmonary disease requiring prolonged treatment, or as a steroid-sparing intervention in cases with high risk of steroid toxicity. Biologic therapies might be considered as additive therapy if non-biologics are insufficiently effective or are not tolerated with initial biologic therapy, usually with a tumour necrosis factor-α inhibitor, typically infliximab.The Delphi methodology provided a platform to gain potentially valuable insight and interim guidance while awaiting evidenced-based contributions.

Long-term Host Immune Response Trajectories Among Hospitalized Patients With Sepsis.

Importance: Long-term immune sequelae after sepsis are poorly understood. Objective: To assess whether abnormalities in the host immune response during hospitalization for sepsis persist after discharge. Design, Settings, and Participants: This prospective, multicenter cohort study enrolled and followed up for 1 year adults who survived a hospitalization for sepsis from January 10, 2012, to May 25, 2017, at 12 US hospitals. Exposures: Circulating levels of inflammation (interleukin 6 and high-sensitivity C-reactive protein [hs-CRP]), immunosuppression (soluble programmed death ligand 1 [sPD-L1]), hemostasis (plasminogen activator inhibitor 1 and D-dimer), endothelial dysfunction (E-selectin, intercellular adhesion molecule 1, and vascular cell adhesion molecule 1), and oxidative stress biomarkers were measured at 5 time points during and after hospitalization for sepsis for 1 year. Individual biomarker trajectories and patterns of trajectories across biomarkers (phenotypes) were identified. Main Outcomes and Measures: Outcomes were adjudicated centrally and included all-cause and cause-specific readmissions and mortality. Results: A total of 483 patients (mean [SD] age, 60.5 [15.2] years; 265 [54.9%] male) who survived hospitalization for sepsis were included in the study. A total of 376 patients (77.8%) had at least 1 chronic disease, and their mean (SD) Sequential Organ Failure Assessment score was 4.2 (3.0). Readmissions were common (485 readmissions in 205 patients [42.5%]), and 43 patients (8.9%) died by 3 months, 56 patients (11.6%) died by 6 months, and 85 patients (17.6%) died by 12 months. Elevated hs-CRP levels were observed in 23 patients (25.8%) at 3 months, 26 patients (30.2%) at 6 months, and 23 patients (25.6%) at 12 months, and elevated sPD-L1 levels were observed in 45 patients (46.4%) at 3 months, 40 patients (44.9%) at 6 months, and 44 patients (49.4%) at 12 months. Two common phenotypes were identified based on hs-CRP and sPDL1 trajectories: high hs-CRP and sPDL1 levels (hyperinflammation and immunosuppression phenotype [326 of 477 (68.3%)]) and normal hs-CRP and sPDL1 levels (normal phenotype [143 of 477 (30.0%)]). These phenotypes had similar clinical characteristics and clinical course during hospitalization for sepsis. Compared with normal phenotype, those with the hyperinflammation and immunosuppression phenotype had higher 1-year mortality (odds ratio, 8.26; 95% CI, 3.45-21.69; P < .001), 6-month all-cause readmission or mortality (hazard ratio [HR], 1.53; 95% CI, 1.10-2.13; P = .01), and 6-month readmission or mortality attributable to cardiovascular disease (HR, 5.07; 95% CI, 1.18-21.84; P = .02) or cancer (HR, 5.15; 95% CI, 1.25-21.18; P = .02). These associations were adjusted for demographic characteristics, chronic diseases, illness severity, organ support, and infection site during sepsis hospitalization and were robust in sensitivity analyses. Conclusions and Relevance: In this study, persistent elevation of inflammation and immunosuppression biomarkers occurred in two-thirds of patients who survived a hospitalization for sepsis and was associated with worse long-term outcomes.

Immune Checkpoint Inhibition in Sepsis: A Phase 1b Randomized, Placebo-Controlled, Single Ascending Dose Study of Antiprogrammed Cell Death-Ligand 1 Antibody (BMS-936559).

OBJECTIVES: To assess for the first time the safety and pharmacokinetics of an antiprogrammed cell death-ligand 1 immune checkpoint inhibitor (BMS-936559; Bristol-Myers Squibb, Princeton, NJ) and its effect on immune biomarkers in participants with sepsis-associated immunosuppression. DESIGN: Randomized, placebo-controlled, dose-escalation. SETTING: Seven U.S. hospital ICUs. STUDY POPULATION: Twenty-four participants with sepsis, organ dysfunction (hypotension, acute respiratory failure, and/or acute renal injury), and absolute lymphocyte count less than or equal to 1,100 cells/µL. INTERVENTIONS: Participants received single-dose BMS-936559 (10-900 mg; n = 20) or placebo (n = 4) infusions. Primary endpoints were death and adverse events; key secondary endpoints included receptor occupancy and monocyte human leukocyte antigen-DR levels. MEASUREMENTS AND MAIN RESULTS: The treated group was older (median 62 yr treated pooled vs 46 yr placebo), and a greater percentage had more than 2 organ dysfunctions (55% treated pooled vs 25% placebo); other baseline characteristics were comparable. Overall mortality was 25% (10 mg dose: 2/4; 30 mg: 2/4; 100 mg: 1/4; 300 mg: 1/4; 900 mg: 0/4; placebo: 0/4). All participants had adverse events (75% grade 1-2). Seventeen percent had a serious adverse event (3/20 treated pooled, 1/4 placebo), with none deemed drug-related. Adverse events that were potentially immune-related occurred in 54% of participants; most were grade 1-2, none required corticosteroids, and none were deemed drug-related. No significant changes in cytokine levels were observed. Full receptor occupancy was achieved for 28 days after BMS-936559 (900 mg). At the two highest doses, an apparent increase in monocyte human leukocyte antigen-DR expression (> 5,000 monoclonal antibodies/cell) was observed and persisted beyond 28 days. CONCLUSIONS: In this first clinical evaluation of programmed cell death protein-1/programmed cell death-ligand 1 pathway inhibition in sepsis, BMS-936559 was well tolerated, with no evidence of drug-induced hypercytokinemia or cytokine storm, and at higher doses, some indication of restored immune status over 28 days. Further randomized trials on programmed cell death protein-1/programmed cell death-ligand 1 pathway inhibition are needed to evaluate its clinical safety and efficacy in patients with sepsis.

IL-13-regulated Macrophage Polarization during Granuloma Formation in an In Vitro Human Sarcoidosis Model.

The mechanisms underlying abnormal granuloma formation in patients with sarcoidosis are complex and remain poorly understood. A novel in vitro human granuloma model was used to determine the molecular mechanisms of granuloma genesis in patients with sarcoidosis in response to putative disease-causing mycobacterial antigens. Peripheral blood mononuclear cells (PBMCs) from patients with active sarcoidosis and from normal, disease-free control subjects were incubated for 7 days with purified protein derivative-coated polystyrene beads. Molecular responses, as reflected by differential expression of genes, extracellular cytokine patterns, and cell surface receptor expression, were analyzed. Unbiased systems biology approaches were used to identify signaling pathways engaged during granuloma formation. Model findings were compared with human lung and mediastinal lymph node gene expression profiles. Compared with identically treated PBMCs of control subjects (n = 5), purified protein derivative-treated sarcoidosis PBMCs (n = 6) were distinguished by the formation of cellular aggregates resembling granulomas. Ingenuity Pathway Analysis of differential expression gene patterns identified molecular pathways that are primarily regulated by IL-13, which promotes alternatively activated (M2) macrophage polarization. M2 polarization was further demonstrated by immunohistochemistry performed on the in vitro sarcoidosis granuloma-like structures. IL-13-regulated gene pathways were confirmed in human sarcoidosis lung and mediastinal lymph node tissues. The in vitro human sarcoidosis granuloma model provides novel insights into early granuloma formation, particularly IL-13 regulation of molecular networks that regulate M2 macrophage polarization. M2 macrophages are predisposed to aggregation and multinucleated giant cell formation, which are characteristic features of sarcoidosis granulomas. Clinical trial registered with www.clinicaltrials.gov (NCT01857401).

Role of imbalance between Th17 and regulatory T-cells in sarcoidosis.

PURPOSE OF REVIEW: A relatively new class of CD4 expressing T cells that also express and release interleukin-17 (Th17 cells) is gaining attention based on their capacity to regulate inflammatory responses in a spectrum of chronic autoimmune diseases. The purpose of this review is to consider recent studies relating to the critical role played by Th17 cells in the pathogenesis of sarcoidosis. RECENT FINDINGS: Th17 cells are unique in their capacity to adapt to local molecular cues to variably promote or suppress inflammation. On the basis of knowledge established originally in the context of autoimmune disorders, recent investigations indicate that Th17 cells are instrumental in all stages of granuloma evolution, including granuloma formation, maintenance and resolution. Recent research shed light on the mechanisms regulating Th17 cell plasticity and the implications for sarcoidosis disease progression, such as the mechanisms by which regulatory T cells (Tregs) promote resolution of Th17-mediated inflammation. SUMMARY: The balance between Th17 cells and Tregs in sarcoidosis patients has important implications for clinicians and clinical researchers seeking more reliable prognostic markers and more targeted therapeutic agents.

Potential immunotherapies for sarcoidosis.

INTRODUCTION: Sarcoidosis is a chronic granulomatous inflammatory disease that commonly causes lung disease, but can affect other vital organs and tissues. The cause of sarcoidosis is unknown, and current therapies are commonly limited by lack of efficacy, adverse side effects, and excessive cost. AREAS COVERED: The manuscript will provide a review of current concepts relating to the pathogenesis of sarcoidosis, and how these disease mechanisms may be leveraged to develop more effective treatments for sarcoidosis. It provides only a brief summary of currently accepted therapy, while focusing more extensively on potential novel therapies. EXPERT OPINION: Current sarcoidosis therapeutic agents primarily target the M1 or pro-inflammatory pathways. Agents that prevent M2 polarization, a regulatory phenotype favoring fibrosis, are attractive treatment alternatives that could potentially prevent fibrosis and associated life threatening complications. Effective treatment of sarcoidosis potentially requires simultaneous modulation both M1/M2 polarization instead of suppressing one pathway over the other to restore immune competent and inactive (M0) macrophages.

Proceedings of the Americas Association of Sarcoidosis and Other Granulomatous Diseases (AASOG) 2017 annual meeting.

On April 7th and 8th, 2017; the Americas Association for Sarcoidosis and Other Granulomatous Diseases (AASOG) held its annual scientific conference titled "Combining Transformative Sarcoidosis Research and Outreach to Improve Health Disparities" at the Penn State Health, Hershey Campus Conference Center. Participants came from geographically diverse areas of the United States. The demographics of meeting speakers and attendees reflected the gender, racial and ethnic diversity of those who are engaged in the treatment of the disease. The AASOG meeting was held in conjunction with an FSR-sponsored sarcoidosis patient-physician conference, providing a unique forum to enhance communication between patients, providers and researchers. Cutting edge topics at the meeting included immunology, microbiome, genomics, and challenges in diagnosis and treatment of vulnerable populations. The meeting's clinical foci were neurosarcoidosis, fatigue, and small fiber neuropathy. (Sarcoidosis Vasc Diffuse Lung Dis 2018; 35: 91-94).