Marcel Veltkamp

Methotrexate vs Azathioprine in Second-line Therapy of Sarcoidosis

BACKGROUND Steroids remain the first-choice therapeutic in sarcoidosis; however, long-term use is associated with toxicity. Evidence defining the best second-line therapeutic is currently lacking. The aim of this study was to compare the effect of methotrexate and azathioprine on prednisone tapering, pulmonary function, and side effects in the second-line treatment of sarcoidosis. METHODS An international retrospective cohort study was performed, reviewing all patients with sarcoidosis who started methotrexate or azathioprine until 2 years after initiation or discontinuation. A linear mixed model with FEV1, vital capacity (VC), diffusing capacity of lung for carbon monoxide (DLCO), and prednisone dose changes over time as end points was used. Side effects were compared with χ2 tests. RESULTS Two hundred patients were included, of whom 145 received methotrexate and 55 azathioprine. Prednisone daily dose decreased a mean of 6.32 mg/y (P < .0001) while on therapy, with a similar steroid-sparing capacity for methotrexate and azathioprine. Of all patients completing 1 year of therapy, 70% had a reduction in daily prednisone dose of at least 10 mg. FEV1 showed a mean increase of 52 mL/y (P = .006) and VC of 95 mL/y (P = .001) in both treatment groups. DLCO % predicted increased, with a mean of 1.23%/y (P = .018). There were more patients with infections in the azathioprine group (34.6% vs 18.1%, P = .01), but no differences regarding other side effects. CONCLUSIONS This retrospective study comparing the effect of second-line therapy in sarcoidosis shows that both methotrexate and azathioprine have significant steroid-sparing potency, a similar positive effect on lung function, and comparable side effects, except for a higher infection rate in the azathioprine group.

Linkage between Toll-like receptor (TLR) 2 promotor and intron polymorphisms: functional effects and relevance to sarcoidosis

The intracellular pathogens Propionibacterium acnes and Mycobacterium tuberculosis have been leading suspects as the cause of sarcoidosis, a systemic disorder characterized by the formation of non‐caseating granulomas. Toll‐like receptor (TLR) 2 is important in the innate immune response against both pathogens, and is therefore of interest in sarcoidosis research. In the present study, three single nucleotide polymorphisms and one dinucleotide repeat polymorphism in the TLR‐2 gene were genotyped in 419 sarcoidosis patients, divided into a study cohort and a validation cohort, and 196 healthy controls. In the study cohort we found a significant increase in prevalence of the AA‐genotype at promotor location −16934 in patients with chronic disease compared to patients with acute/self‐remitting sarcoidosis (34·5% versus 15·9%, respectively, P = 0·006, Pc = 0·019). These results could not be confirmed in our validation cohort, implicating a possible role for TLR‐2 genetics in only a small percentage of sarcoidosis patients. Furthermore, linkage was found between the promotor polymorphism −16934 A/T and the number of GT repeats in intron 1 (P < 0·0001). After in vitro stimulation of peripheral blood mononuclear cells (PMBCs) with different TLR‐2 agonists, a correlation between induction of TNF‐α (P = 0·008), interleukin (IL)‐12 (P = 0·008) as well as IL‐6 (P = 0·02), and the number of GT repeats was observed. In conclusion, the data show that polymorphisms in TLR‐2 might be important in a small group of sarcoidosis patients and that their functional consequences explain partly some of the variance in cytokine pattern observed in different clinical phenotypes of this disease.

Toll-like receptor (TLR) 4 polymorphism Asp299Gly is not associated with disease course in Dutch sarcoidosis patients.

The aetiology of sarcoidosis, a systemic disorder characterized by the formation of non‐caseating granulomas in variable organs, remains enigmatic. Clarification is hampered by heterogeneity in disease phenotypes and course, due partly to the influence of a variety of genetic and environmental factors. Multiple studies have pointed towards bacteria as possible causative agents. Toll‐like receptors (TLR) are innate immunity receptors important in the immune response against pathogens. TLR‐4, together with CD14 and MD‐2, is an essential receptor for the recognition of lipopolysaccharide (LPS), unique to the cell wall of Gram‐negative bacteria. Recently, an association between TLR‐4 polymorphism Asp299Gly, leading to a change in the extracellular domain of the receptor and possible hyporesponsiveness to LPS, and a chronic course of sarcoidosis was found in German patients. In the present study this polymorphism was genotyped in 156 Dutch sarcoidosis patients and 200 healthy Dutch controls using dual‐labelled fluorescent oligonucleotides. No differences were found in allelic distributions between patients and controls (P = 0·79) or within the different clinical entities of the sarcoidosis group (P = 0·44). Importantly, there were no differences between the Dutch and German sarcoidosis patients (P = 0·62). However, the allelic distribution of the Asp299Gly polymorphism differed significantly between both control groups (P = 0·04). This study highlights the importance of testing a reported gene association in a distinct population when performing genetic association studies.

Genetic variation in the Toll-like receptor gene cluster (TLR10-TLR1-TLR6) influences disease course in sarcoidosis

Sarcoidosis is an inflammatory disease of unknown etiology. Various microorganisms have been proposed as etiologic agent suggesting a role for pattern-recognition receptors such as Toll-like receptors (TLRs) in disease pathogenesis, with a special interest in TLR-2. TLR-10, TLR-1, and TLR-6 act as co-receptors for TLR-2 and the genes encoding these receptors are located in a gene cluster on chromosome 4. The aim of our study was to assess differences in genetic variation in the TLR10-TLR1-TLR6 gene cluster between patients and controls. A total of eight single nucleotide polymorphisms were genotyped in 447 healthy controls and 533 patients, divided in 425 with sarcoidosis and 108 with Löfgrens syndrome. Comparison of the total patient cohort with controls showed that the allele frequencies of rs1109695, rs7658893 (TLR-10), and rs5743604 as well as rs5743594 (TLR-1) differed significantly. Haplotype analysis showed that the most common haplotype found was significantly decreased in patients with chronic sarcoidosis. Furthermore, a less common haplotype was found to be significantly increased in patients with Löfgrens syndrome as well as sarcoidosis patients with self-remitting disease, indicating that it could act as a disease modifying haplotype. In conclusion, our study suggests that absence of the common haplotype in the TLR10-TLR1-TLR6 gene cluster increases the risk of developing chronic disease in patients already affected by sarcoidosis. Based on their role as co-receptors for TLR-2, this study supports the growing evidence that aberrant TLR-2 function is important in sarcoidosis disease pathogenesis.

Toll-like receptor (TLR)-9 genetics and function in sarcoidosis.

Sarcoidosis is a systemic disorder characterized by the formation of non‐caseating granulomas in variable organs. Toll‐like receptor (TLR)‐9 is important in the innate immune response against both Mycobacterium tuberculosis and Propionibacterium acnes, candidate causative agents in sarcoidosis. The aim of our study was to investigate possible genetic and functional differences in TLR‐9 between patients and controls. TLR‐9 single nucleotide polymorphisms were genotyped in 533 patients and divided into a study cohort and validation cohort and 185 healthy controls. Furthermore, part of the promotor as well as the entire coding region of the TLR‐9 gene were sequenced in 20 patients in order to detect new mutations. No genetic differences were found between patients and controls. In order to test TLR‐9 function, peripheral blood mononuclear cells (PBMCs) of 12 healthy controls and 12 sarcoidosis patients were stimulated with a TLR‐9 agonist and the induction of interleukin (IL)‐6, interferon (IFN)‐γ and IL‐23 was measured. Sarcoidosis patients produce significantly less IFN‐γ upon stimulation with different stimuli. Regarding IL‐23 production, a significant difference between patients and controls was found only after stimulation with the TLR‐9 agonist. In conclusion, we did not find genetic differences in the TLR‐9 gene between sarcoidosis patients and controls. Sarcoidosis patients produce less IFN‐γ regardless of the stimulating agent, probably reflecting the anergic state often seen in their peripheral blood T lymphocytes. The differences in TLR‐9‐induced IL‐23 production could indicate that functional defects in the TLR‐9 pathway of sarcoidosis patients play a role in disease susceptibility or evolution.

Increased Expression of CD16, CD69, and Very Late Antigen-1 on Blood Monocytes in Active Sarcoidosis

BACKGROUND Different types of immune cells are involved in the formation of granulomas, a hallmark of pulmonary sarcoidosis. Proinflammatory monocytes are activated circulating monocytes thought to be related to the initial events of granuloma formation. We tested the hypothesis that peripheral blood monocytes in patients with active pulmonary sarcoidosis have an activated phenotype and, secondly, that measuring this activation status can provide a new tool for monitoring disease activity. METHODS Blood was collected of 23 steroid-naive patients presenting with pulmonary sarcoidosis and 10 healthy control subjects. Expression of CD16 (Fc-gamma type III receptor), CD69 (a general activation marker of cells of the hematopoietic lineage), and the integrin very late antigen (VLA)-1 (on interaction with extracellular matrix compounds mediates cell adhesion) was measured by flow cytometry. RESULTS Percentages of monocytes expressing CD16, CD69, and VLA-1 in patients vs control subjects were 56.2 +/- 4.1% vs 12.2 +/- 2.4% (p < 0.0001), 87.3 +/- 2.1% vs 8.6 +/- 3.3% (p < 0.0001), and 66.5 +/- 3.6% vs 11.2 +/- 2.3% (p < 0.0001), respectively. Moreover, the CD69+VLA-1+ monocyte subset, abundantly present at disease presentation, was found to decrease to normal levels during follow-up with disease remission. CONCLUSIONS Peripheral blood monocytes from patients with pulmonary sarcoidosis show a highly activated phenotype. Phenotyping circulating monocytes might be a promising tool for monitoring sarcoidosis disease activity but needs further investigation.

A Global Survey on Whole Lung Lavage in Pulmonary Alveolar Proteinosis.

AFFILIATIONS: From the Department of Pulmonary and Critical Care Medicine, Northwestern University. FINANCIAL/NONFINANCIAL DISCLOSURES: See earlier cited article for author conflicts of interest. CORRESPONDENCE TO: Sean B. Smith, MD, Pulmonary and Critical Care Medicine, Feinberg School of Medicine, Northwestern University, 660 N Westmoreland Rd, Lake Forest, IL 60045; e-mail: sean@northwestern.edu Copyright 2016 Published by Elsevier Inc under license from the American College of Chest Physicians. DOI: http://dx.doi.org/10.1016/j.chest.2016.04.023]

Etiology and Immunopathogenesis of Sarcoidosis: Novel Insights

Abstract Sarcoidosis is a disorder of unknown etiology. It is a systemic disease, frequently involving the lungs, skin, eyes, and lymph nodes. It is characterized by formation of noncaseating granulomas at the site(s) of disease. Sarcoidosis has a complex disease pathogenesis, with involvement of both the innate and adaptive immune systems. Several innate immune system receptors including NOD‐like receptors and Toll‐like receptors appear to be involved in the development of sarcoidosis as well as cellular players such as dendritic cells and macrophages. Furthermore, lymphocytes from the adaptive immune system including Th1, Th17, regulatory T cells, and B cells are likely to play a role in the sarcoidosis disease pathogenesis as well. Possibly, genetic susceptibility and exposure to particular etiologic agents including mycobacterial and propionibacterial antigens, metals, and silica can cause sarcoidosis. Besides exogenous triggers, also self‐compounds such as serum amyloid A and vimentin, have been found to play a role in the development of sarcoidosis. It is likely that sarcoidosis does not have one single cause but rather is the result of the interplay between different etiologic agents and the immune system in predisposed individuals.

Efficacy and safety of infliximab biosimilar Inflectra® in severe sarcoidosis

BACKGROUND Infliximab, a monoclonal antibody against tumor necrosis factor alpha (TNF-α) is effective third-line therapy in severe sarcoidosis. The originator product of Infliximab, Remicade®, is expensive, limiting universal access. Recently, a less expensive biosimilar of infliximab, Inflectra®, has become available, but the efficacy and tolerability has not been studied in sarcoidosis. METHODS In this retrospective cohort study, 29 patients treated with the infliximab biosimilar Inflectra®, were analysed. Patients received Inflectra® intravenously monthly at a dose of 5 mg/kg. We measured trough levels before every infusion. Before and after 6 months of induction therapy pulmonary function and disease activity were evaluated using Standardised Uptake Value (SUV) of the 18F-fluorodeoxyglucose by positron emission tomography (18F-FDG PET), soluble interleukin-2 receptor (sIL-2R), angiotensin converting enzyme (ACE) and health-related quality of life (HRQOL). RESULTS In patients with pulmonary sarcoidosis as main treatment indication (n = 15) the predicted FVC improved with 8.1%, p < 0.05. Furthermore, in the whole group HRQoL improved significantly (p < 0.001), whereas SUVmax and sIL-2R significantly reduced (p < 0.001 and p = 0.001 respectively). Hospitalisation due to infections occurred in four patients. None of the patients discontinued Inflectra® due to side-effects. Furthermore, all patients had detectable trough levels indicating development of neutralizing antibodies. CONCLUSION Infliximab biosimilar Inflectra® seems effective in the treatment of refractory sarcoidosis with a comparable safety profile to the reference product Remicade®. Inflectra® can be considered as an alternative and less expensive option for patients with refractory sarcoidosis.

Understanding the priorities for women diagnosed with lymphangioleiomyomatosis: a patient perspective

Lymphangioleiomyomatosis (LAM) is a rare lung disease that almost exclusively affects women and develops in about one in 400 000 adult females. The European Lung Foundation worked closely with one of the patient organisations within its network, the European LAM Federation, to raise awareness of LAM at the 2014 European Respiratory Society International Congress in Munich, Germany. In addition, an invitation-only workshop with 45 individuals from 13 countries was held to discuss the priorities for women in Europe living with the disease. The need for ongoing collaboration to improve knowledge of this rare lung condition with healthcare professionals across Europe was highlighted. Patient organisations and @EuropeanLung have surveyed the priorities of people living with LAM http://ow.ly/10gTld