Chronic beryllium disease (CBD), a granulomatous disease with similarities to sarcoidosis, arises only in individuals exposed to beryllium. Inhaled beryllium can elicit a T-cell-dominated alveolitis ...leading nonnecrotizing granulomata. CBD can be distinguished from sarcoidosis by demonstrating beryllium sensitization in a lymphocyte proliferation test.
Beryllium exposure usually occurs in an occupational setting. Because of the diagnosis of CBD in a patient without evident beryllium exposure, we performed a beryllium-lymphocyte proliferation test (BeLPT) among his work colleagues.
This field study investigated a cohort of work colleagues without obvious beryllium exposure. Twenty-one of 30 individuals were assessed in our outpatient clinic for beryllium sensitization. Therefore, BeLPT was performed with freshly collected peripheral blood mononuclear cells. Data were extracted from clinical charts, including geographical data. Beryllium content in dust samples collected at the workplace was measured by graphite-furnace atomic absorption spectroscopy and was compared with samples from different areas of Germany.
For the initial patient, the diagnosis of sarcoidosis was reclassified as CBD based on two positive BeLPT results. Assessment of his workplace did not identify a source of beryllium. However, BeLPTs performed on his workmates demonstrated beryllium sensitization in 5 of 21 individuals, suggesting a local beryllium source. Concrete dust obtained from the building yard, the workplace of the index patient, contained high amounts of beryllium (1138 ± 162 μg/kg), whereas dust from other localities (control samples) showed much lower beryllium content (range, 147 ± 18-452 ± 206 μg/kg). Notably, the control dust collected from different places all over Germany exhibit different beryllium concentrations.
We describe a cluster of beryllium-sensitized workers from an industry not related to beryllium caused by environmental exposure to beryllium-containing concrete dust, which exhibited markedly elevated beryllium content. Importantly, analyses of dust samples collected from different localities showed that they contain markedly different amounts of beryllium. Thus, besides workplace-related exposure, environmental factors also are capable of eliciting a beryllium sensitization.
Elevated levels of extracellular adenosine triphosphate (ATP) modulate immunologic pathways and are considered to be a danger signal in inflammation, lung fibrosis and cancer. Macrophages can be ...classified into two main types: M1 macrophages are classically activated, pro-inflammatory macrophages, whereas M2 macrophages are alternatively activated, pro-fibrotic macrophages. In this study, we examined the effect of ATP on differentiation of native human monocytes into these macrophage subtypes. We characterized M1 and M2 like macrophages by their release of Interleukin-1beta (IL-1β) and Chemokine (C-C motif) ligand 18 (CCL18), respectively.
Monocytes were stimulated with ATP or the P2X7 receptor agonist Benzoylbenzoyl-ATP (Bz-ATP), and the production of various cytokines was analyzed, with a particular focus on CCL18 and IL-1β, along with the expression of different purinergic receptors. Over a 72 h period of cell culture, monocytes spontaneously differentiated to M2 like macrophages, as indicated by an increased release of CCL18. Immediate stimulation of monocytes with ATP resulted in a dose-dependent reduction in CCL18 release, but had no effect on the concentration of IL-1β. In contrast, delayed stimulation with ATP had no effect on either CCL18 or IL-1β release. Similar results were observed in a model of inflammation using lipopolysaccharide-stimulated human monocytes. Stimulation with the P2X7 receptor agonist Bz-ATP mimicked the effect of ATP on M2-macrophage differentiation, indicating that P2X7 is involved in ATP-induced inhibition of CCL18 release. Indeed, P2X7 was downregulated during spontaneous M2 differentiation, which may partially explain the ineffectiveness of late ATP stimulation of monocytes. However, pre-incubation of monocytes with PPADS, Suramin (unselective P2X- and P2Y-receptor blockers) and KN62 (P2X7-antagonist) failed to reverse the reduction of CCL18 by ATP.
ATP prevents spontaneous differentiation of monocytes into M2-like macrophages in a dose- and time-dependent manner. These effects were not mediated by P2X and P2Y receptors.
Activin A strongly influences immune responses; yet, few studies have examined its role in infectious diseases. We measured serum activin A levels in two independent tuberculosis (TB) patient cohorts ...and in patients with pneumonia and sarcoidosis. Serum activin A levels were increased in TB patients compared to healthy controls, including those with positive tuberculin skin tests, and paralleled severity of disease, assessed by X-ray scores. In pneumonia patients, serum activin A levels were also raised, but in sarcoidosis patients, levels were lower. To determine whether blockade of the activin A signaling axis could play a functional role in TB, we harnessed a soluble activin type IIB receptor fused to human IgG1 Fc, ActRIIB-Fc, as a ligand trap in a murine TB model. The administration of ActRIIB-Fc to
-infected mice resulted in decreased bacterial loads and increased numbers of CD4 effector T cells and tissue-resident memory T cells in the lung. Increased frequencies of tissue-resident memory T cells corresponded with downregulated T-bet expression in lung CD4 and CD8 T cells. Altogether, the results suggest a disease-exacerbating role of ActRIIB signaling pathways. Serum activin A may be useful as a biomarker for diagnostic triage of active TB or monitoring of anti-tuberculosis therapy.
Tuberculosis remains the leading cause of death by a bacterial pathogen. The etiologic agent of tuberculosis,
, can remain dormant in the infected host for years before causing disease. Significant effort has been made to identify biomarkers that can discriminate between latently infected and actively diseased individuals. We found that serum levels of the cytokine activin A were associated with increased lung pathology and could discriminate between active tuberculosis and tuberculin skin-test-positive healthy controls. Activin A signals through the ActRIIB receptor, which can be blocked by administration of the ligand trap ActRIIB-Fc, a soluble activin type IIB receptor fused to human IgG1 Fc. In a murine model of tuberculosis, we found that ActRIIB-Fc treatment reduced mycobacterial loads. Strikingly, ActRIIB-Fc treatment significantly increased the number of tissue-resident memory T cells. These results suggest a role for ActRIIB signaling pathways in host responses to
and activin A as a biomarker of ongoing disease.
Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease of unknown origin, with a median patient survival time of ~3 years after diagnosis without anti-fibrotic therapy. It is characterized by ...progressive fibrosis indicated by increased collagen deposition and high numbers of fibroblasts in the lung. It has been demonstrated that CCL18 induces collagen and αSMA synthesis in fibroblasts. We aimed to identify the CCL18 receptor responsible for its pro-fibrotic activities.
We used a random phage display library to screen for potential CCL18-binding peptides, demonstrated its expression in human lungs and fibroblast lines by PCR and immunostaining and verified its function in cell lines.
We identified CCR6 (CD196) as a CCL18 receptor and found its expression in fibrotic lung tissue and lung fibroblast lines derived from fibrotic lungs, but it was almost absent in control lines and tissue. CCL18 induced receptor internalization in a CCR6-overexpressing cell line. CCR6 blockade in primary human lung fibroblasts reduced CCL18-induced FGF2 release as well as collagen-1 and αSMA expression. Knockdown of CCR6 in a mouse fibroblast cell line abolished the induction of collagen and α-smooth muscle actin expression.
Our data indicate that CCL18 triggers pro-fibrotic processes via CCR6, highlighting its role in fibrogenesis.
Non-small cell lung cancer (NSCLC)11NSCLC: Non-small cell lung cancer; 18FDG: 18fluorine fluorodeoxyglucose; PET: positron emission tomography; CT: computed tomography; SUV: standardized uptake ...value; TAM: tumor-associated macrophage; CCL18: CC-chemokine ligand 18; SUVmax: maximum standardized uptake value; SQC: squamous carcinoma; AC: adenocarcinoma; FEV1: forced expiratory volume in 1 s; is one of the most common malignancies in the western world 1. Despite multiple therapeutic and diagnostic advances, the overall survival is low and recurrence of NSCLC is a common problem with different treatment regimens. The inclusion of 18fluorine fluorodeoxyglucose (18FDG) positron emission tomography (PET) in combination with computed tomography (CT) in clinical practice was revolutionary for the staging of NSCLC 2. 18FDG-PET/CT provides morphological, functional, and metabolic information about the tumor, which is usually highly, metabolically active. Due to the increased glucose uptake, 18FDG is actively accumulatedin the tumor tissues, resulting in an increased standardized uptake value (SUV). The tumor tissue itself consists of neoplastic cells, extracellular matrix, fibroblasts, and various immune cells. These immune cells include tumor-infiltrating lymphocytes, regulatory T cells, and macrophages. Macrophages have different activation patterns and play an essential role in inflammation and cancer. In particular, tumor-associated macrophages (TAMs) are a specialized group of alternatively activated or M2 macrophages. TAMs release several chemokines that are different from those released by classically activated macrophages found in an inflammatory environment. One of the most important chemokines released by TAMs is CC-chemokine ligand 18 (CCL18). Although CCL18 is present in healthy subjects, its levels are significantly elevated in the serum of patients with NSCLC. It correlates with overall survival and tumor stage in several malignant diseases 3,4. A recurring problem is that increased glucose metabolism can be found in the inflammatory tissue, which can also lead to an increased SUV in 18FDG PET/CT, lowering its oncological specificity 5. In a previous study, we demonstrated that serum CCL18 levels can be used to differentiate between patients with NSCLC and healthy subjects 3. Hence, we investigated the correlation between serum CCL18 levels and the maximum standardized uptake value (SUVmax) of the primary tumor using 18FDG-PET/CT. We found a significant correlation between the SUVmax of the primary tumor and the serum CCL18 level. The data are important because they can be used to draw conclusions about immunometabolism. Furthermore, they can serve as basis for future prospective clinical studies.
Surfactant proteins (SPs) are important lipoprotein complex components, expressed in alveolar epithelial cells type II (AEC-II), and playing an essential role in maintenance of alveolar integrity and ...host defence. Because expressions of SPs are regulated by cyclic adenosine monophosphate (cAMP), we hypothesized that phosphodiesterase (PDE) inhibitors, influence SP expression and release. Analysis of PDE activity of our AEC-II preparations revealed that PDE4 is the major cAMP hydrolysing PDE in human adult AEC-II. Thus, freshly isolated human AEC-II were stimulated with two different concentrations of the PDE4 inhibitor roflumilast-N-oxide (3 nM and 1 µM) to investigate the effect on SP expression. SP mRNA levels disclosed a large inter-individual variation. Therefore, the experiments were grouped by the basal SP expression in low and high expressing donors. AEC-II stimulated with Roflumilast-N-oxide showed a minor increase in SP-A1, SP-C and SP-D mRNA mainly in low expressing preparations. To overcome the effects of different basal levels of intracellular cAMP, cyclooxygenase was blocked by indomethacin and cAMP production was reconstituted by prostaglandin E2 (PGE2). Under these conditions SP-A1, SP-A2, SP-B and SP-D are increased by roflumilast-N-oxide in low expressing preparations. Roflumilast-N-oxide fosters the expression of SPs in human AEC-II via increase of intracellular cAMP levels potentially contributing to improved alveolar host defence and enhanced resolution of inflammation.
T cells recognize antigens via their cell surface TCR and are classified as either αβ or γδ depending on the variable chains in their TCR, α and β or γ and δ, respectively. Both αβ and γδ TCRs also ...contain several invariant chains, including CD3δ, which support surface TCR expression and transduce the TCR signal. Mutations in variable chains would be expected to affect a single T cell lineage, while mutations in the invariant chains would affect all T cells. Consistent with this, all CD3δ-deficient patients described to date showed a complete block in T cell development. However, CD3δ-KO mice have an αβ T cell-specific defect. Here, we report 2 unrelated cases of SCID with a selective block in αβ but not in γδ T cell development, associated with a new splicing mutation in the CD3D gene. The patients' T cells showed reduced CD3D transcripts, CD3δ proteins, surface TCR, and early TCR signaling. Their lymph nodes showed severe T cell depletion, recent thymus emigrants in peripheral blood were strongly decreased, and the scant αβ T cells were oligoclonal. T cell-dependent B cell functions were also impaired, despite the presence of normal B cell numbers. Strikingly, despite the specific loss of αβ T cells, surface TCR expression was more reduced in γδ than in αβ T cells. Analysis of individuals with this CD3D mutation thus demonstrates the contrasting CD3δ requirements for αβ versus γδ T cell development and TCR expression in humans and highlights the diagnostic and clinical relevance of studying both TCR isotypes when a T cell defect is suspected.
Sarcoidosis is a systemic inflammatory disease of unknown aetiology, influenced by genetic and environmental factors. However, the loci so far identified for sarcoidosis explain only a part of its ...assumed heritability. To identify further susceptibility loci, we performed a genome-wide association analysis using the Affymetrix 6.0 Human GeneChip followed by validation and replication stages. After quality control, 637 cases, 1233 controls and 677 619 single-nucleotide polymorphisms (SNPs) were available for an initial screening. 99 SNPs were selected for validation in an independent study panel (1664 patients, 2932 controls). SNP rs1050045 was significantly associated with sarcoidosis (corrected p=0.0215) in the validation panel and yielded a p-value of 9.22 × 10(-8) (OR 1.24) in the meta-analysis of the screening and validation stage. A meta-analysis of three populations from Germany, the Czech Republic and Sweden confirmed this finding (p = 0.024; OR 1.14). Fine-mapping and mRNA expression studies pointed to osteosarcoma amplified 9 (OS9) as the most likely candidate for the underlying risk factor. The OS9 protein plays an important role in endoplasmic reticulum-associated protein degradation and acts during Toll-like receptor induced activation of myeloid cells. Expression analyses of OS9 mRNA provide evidence for a functional mechanism underlying the detected association signal.
Non-small cell lung cancer (NSCLC) is one of the most common malignancies in the western world 1. Despite multiple therapeutic and diagnostic advances, the overall survival is low and recurrence of ...NSCLC is a common problem with different treatment regimens. The inclusion of
fluorine fluorodeoxyglucose (
FDG) positron emission tomography (PET) in combination with computed tomography (CT) in clinical practice was revolutionary for the staging of NSCLC 2.
FDG-PET/CT provides morphological, functional, and metabolic information about the tumor, which is usually highly, metabolically active. Due to the increased glucose uptake,
FDG is actively accumulatedin the tumor tissues, resulting in an increased standardized uptake value (SUV). The tumor tissue itself consists of neoplastic cells, extracellular matrix, fibroblasts, and various immune cells. These immune cells include tumor-infiltrating lymphocytes, regulatory T cells, and macrophages. Macrophages have different activation patterns and play an essential role in inflammation and cancer. In particular, tumor-associated macrophages (TAMs) are a specialized group of alternatively activated or M2 macrophages. TAMs release several chemokines that are different from those released by classically activated macrophages found in an inflammatory environment. One of the most important chemokines released by TAMs is CC-chemokine ligand 18 (CCL18). Although CCL18 is present in healthy subjects, its levels are significantly elevated in the serum of patients with NSCLC. It correlates with overall survival and tumor stage in several malignant diseases 3,4. A recurring problem is that increased glucose metabolism can be found in the inflammatory tissue, which can also lead to an increased SUV in
FDG PET/CT, lowering its oncological specificity 5. In a previous study, we demonstrated that serum CCL18 levels can be used to differentiate between patients with NSCLC and healthy subjects 3. Hence, we investigated the correlation between serum CCL18 levels and the maximum standardized uptake value (SUV
) of the primary tumor using
FDG-PET/CT. We found a significant correlation between the SUV
of the primary tumor and the serum CCL18 level. The data are important because they can be used to draw conclusions about immunometabolism. Furthermore, they can serve as basis for future prospective clinical studies.
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