Anti-Inflammatory Effect of Muscle-Derived Interleukin-6 and Its Involvement in Lipid Metabolism.

Interleukin (IL)-6 has been studied since its discovery for its role in health and diseases. It is one of the most important pro-inflammatory cytokines. IL-6 was reported as an exacerbating factor in coronavirus disease. In recent years, it has become clear that the function of muscle-derived IL-6 is different from what has been reported so far. Exercise is accompanied by skeletal muscle contraction, during which, several bioactive substances, collectively named myokines, are secreted from the muscles. Many reports have shown that IL-6 is the most abundant myokine. Interestingly, it was indicated that IL-6 plays opposing roles as a myokine and as a pro-inflammatory cytokine. In this review, we discuss why IL-6 has different functions, the signaling mode of hyper-IL-6 via soluble IL-6 receptor (sIL-6R), and the involvement of soluble glycoprotein 130 in the suppressive effect of hyper-IL-6. Furthermore, the involvement of a disintegrin and metalloprotease family molecules in the secretion of sIL-6R is described. One of the functions of muscle-derived IL-6 is lipid metabolism in the liver. However, the differences between the functions of IL-6 as a pro-inflammatory cytokine and the functions of muscle-derived IL-6 are unclear. Although the involvement of myokines in lipid metabolism in adipocytes was previously discussed, little is known about the direct relationship between nonalcoholic fatty liver disease and muscle-derived IL-6. This review is the first to discuss the relationship between the function of IL-6 in diseases and the function of muscle-derived IL-6, focusing on IL-6 signaling and lipid metabolism in the liver.

Texture analysis of muscle MRI: machine learning-based classifications in idiopathic inflammatory myopathies.

To develop a machine learning (ML) model that predicts disease groups or autoantibodies in patients with idiopathic inflammatory myopathies (IIMs) using muscle MRI radiomics features. Twenty-two patients with dermatomyositis (DM), 14 with amyopathic dermatomyositis (ADM), 19 with polymyositis (PM) and 19 with non-IIM were enrolled. Using 2D manual segmentation, 93 original features as well as 93 local binary pattern (LBP) features were extracted from MRI (short-tau inversion recovery [STIR] imaging) of proximal limb muscles. To construct and compare ML models that predict disease groups using each set of features, dimensional reductions were performed using a reproducibility analysis by inter-reader and intra-reader correlation coefficients, collinearity analysis, and the sequential feature selection (SFS) algorithm. Models were created using the linear discriminant analysis (LDA), quadratic discriminant analysis (QDA), support vector machine (SVM), k-nearest neighbors (k-NN), random forest (RF) and multi-layer perceptron (MLP) classifiers, and validated using tenfold cross-validation repeated 100 times. We also investigated whether it was possible to construct models predicting autoantibody status. Our ML-based MRI radiomics models showed the potential to distinguish between PM, DM, and ADM. Models using LBP features provided better results, with macro-average AUC values of 0.767 and 0.714, accuracy of 61.2 and 61.4%, and macro-average recall of 61.9 and 59.8%, in the LDA and k-NN classifiers, respectively. In contrast, the accuracies of radiomics models distinguishing between non-IIM and IIM disease groups were low. A subgroup analysis showed that classification models for anti-Jo-1 and anti-ARS antibodies provided AUC values of 0.646-0.853 and 0.692-0.792, with accuracy of 71.5-81.0 and 65.8-78.3%, respectively. ML-based TA of muscle MRI may be used to predict disease groups or the autoantibody status in patients with IIM and is useful in non-invasive assessments of disease mechanisms.

Identification of an immune-related long non-coding RNA signature and nomogram as prognostic target for muscle-invasive bladder cancer.

To identify an immune-related prognostic signature based on long non-coding RNAs (lncRNAs) and find immunotherapeutic targets for bladder urothelial carcinoma, we downloaded RNA-sequencing data from The Cancer Genome Atlas (TCGA) dataset. Functional enrichment analysis demonstrated bladder urothelial carcinoma was related to immune-related functions. We obtained 332 immune-related genes and 262 lncRNAs targeting immune-related genes. We constructed a signature based on eight lncRNAs in training cohort. Patients were classified as high-risk and low-risk according to signature risk score. High-risk patients had poor overall survival compared with low-risk patients (P < 0.001). Multivariate Cox regression suggested the signature was an independent prognostic indicator. The findings were further validated in testing, entire TCGA and external validation cohorts. Gene set enrichment analysis indicated significant enrichment of immune-related phenotype in high-risk group. Immunohistochemistry and online analyses validated the functions of 4 key immune-related genes (LIG1, TBX1, CTSG and CXCL12) in bladder urothelial carcinoma. Nomogram proved to be a good classifier for muscle-invasive bladder cancer through combining the signature. In conclusion, our immune-related prognostic signature and nomogram provided prognostic indicators and potential immunotherapeutic targets for muscle-invasive bladder cancer.

Systematic Evaluation of Kinetics and Distribution of Muscle and Lymph Node Activation Measured by 18F-FDG- and 11C-PBR28-PET/CT Imaging, and Whole Blood and Muscle Transcriptomics After Immunization of Healthy Humans With Adjuvanted and Unadjuvanted Vaccines.

Systems vaccinology has been applied to detect signatures of human vaccine induced immunity but its ability, together with high definition in vivo clinical imaging is not established to predict vaccine reactogenicity. Within two European Commission funded high impact programs, BIOVACSAFE and ADITEC, we applied high resolution positron emission tomography/computed tomography (PET/CT) scanning using tissue-specific and non-specific radioligands together with transcriptomic analysis of muscle biopsies in a clinical model systematically and prospectively comparing vaccine-induced immune/inflammatory responses. 109 male participants received a single immunization with licensed preparations of either AS04-adjuvanted hepatitis B virus vaccine (AHBVV); MF59C-adjuvanted (ATIV) or unadjuvanted seasonal trivalent influenza vaccine (STIV); or alum-OMV-meningococcal B protein vaccine (4CMenB), followed by a PET/CT scan (n = 54) or an injection site muscle biopsy (n = 45). Characteristic kinetics was observed with a localized intramuscular focus associated with increased tissue glycolysis at the site of immunization detected by 18F-fluorodeoxyglucose (FDG) PET/CT, peaking after 1-3 days and strongest and most prolonged after 4CMenB, which correlated with clinical experience. Draining lymph node activation peaked between days 3-5 and was most prominent after ATIV. Well defined uptake of the immune cell-binding radioligand 11C-PBR28 was observed in muscle lesions and draining lymph nodes. Kinetics of muscle gene expression module upregulation reflected those seen previously in preclinical models with a very early (~6hrs) upregulation of monocyte-, TLR- and cytokine/chemokine-associated modules after AHBVV, in contrast to a response on day 3 after ATIV, which was bracketed by whole blood responses on day 1 as antigen presenting, inflammatory and innate immune cells trafficked to the site of immunization, and on day 5 associated with activated CD4+ T cells. These observations confirm the use of PET/CT, including potentially tissue-, cell-, or cytokine/chemokine-specific radioligands, is a safe and ethical quantitative technique to compare candidate vaccine formulations and could be safely combined with biopsy to guide efficient collection of samples for integrated whole blood and tissue systems vaccinology in small-scale but intensive human clinical models of immunization and to accelerate clinical development and optimisation of vaccine candidates, adjuvants, and formulations.

Circumventing cellular immunity by miR142-mediated regulation sufficiently supports rAAV-delivered OVA expression without activating humoral immunity.

Recombinant adeno-associated virus (rAAV)-mediated gene delivery can efficiently target muscle tissues to serve as "biofactories" for secreted proteins in prophylactic and therapeutic scenarios. Nevertheless, efficient rAAV-mediated gene delivery is often limited by host immune responses against the transgene product. The development of strategies to prevent anti-transgene immunity is therefore crucial. The employment of endogenous microRNA (miRNA)-mediated regulation to detarget transgene expression from antigen presenting cells (APCs) has shown promise for reducing immunogenicity. However, the mechanisms underlying miRNA-mediated modulation of anti-transgene immunity by APC detargeting are not fully understood. Using the highly immunogenic ovalbumin (OVA) protein as a proxy for foreign antigens, we show that rAAV vectors containing miR142 binding sites efficiently repress co-stimulatory signals in dendritic cells, significantly blunt the cytotoxic T cell response, allow for sustained transgene expression in skeletal myoblasts, and attenuate clearance of transduced muscle cells in mice. Furthermore, the blunting of humoral immunity against circulating OVA correlates with detargeting of OVA expression from APCs. This demonstrates that incorporating APC-specific miRNA binding sites into rAAV vectors provides an effective strategy for reducing transgene-specific immune response. This approach holds promise for clinical applications where the safe and efficient delivery of a prophylactic or therapeutic protein is desired.

Triggers of inflammatory myopathy: insights into pathogenesis.

The inflammatory myopathies, which include dermatomyositis, polymyositis, and the immune-mediated necrotizing myopathies, are a heterogeneous group of autoimmune diseases that manifest with muscle, skin, or lung damage. Collectively, these autoimmune diseases result from loss of tolerance to a select group of self-antigens, although the precise mechanism through which this occurs is not known. Infection, malignancy, and certain medications including statins and the immune checkpoint inhibitors used in cancer therapy have been identified as potential immunologic triggers of the inflammatory myopathies. Some of these triggers are classically associated with specific myositis-specific autoantibodies (MSAs). The strong association between certain triggers and MSAs provides insights into how an immunologic event can lead to loss of tolerance to specific self-antigens, resulting in autoimmune disease. In this review, we discuss the proposed triggers of the inflammatory myopathies and their associations with MSAs, and provide insights into how these triggers may result in the inflammatory myopathies.

A CCR4 antagonist enhances DC activation and homing to the regional lymph node and shows potent vaccine adjuvant activity through the inhibition of regulatory T-cell recruitment.

CCR4 is a major chemokine receptor expressed by Treg cells that downregulate immune responses. Here, we investigated the role of CCR4-mediated Treg cell recruitment in antigen-specific immune responses. CCR4-deficient mice immunized intramuscularly with ovalbumin (OVA) showed enhanced OVA-specific IgG responses. Furthermore, intramuscular administration of OVA induced the expression of MDC/CCL22, a ligand for CCR4, in macrophages of the muscle tissues, and enhanced the recruitment of CCR4+ Treg cells in wild-type mice, whereas this recruitment of Treg cells was severely impaired in CCR4-deficient mice. Furthermore, OVA-loaded dendritic cells (DCs) derived from the muscle injection site of CCR4-deficient mice had an upregulated expression of the DC activation marker CD40 and 86, and the lymphoid organ homing receptor CCR7 resulting in an increased number of migratory DCs in the regional lymph node. Compound 22, a CCR4 antagonist, also inhibited the recruitment of Treg cells to the muscle tissue, and further enhanced DC activation and homing to the regional lymph node. Consequently, Compound 22 enhanced OVA-specific IgG responses, and the expression levels of IL-4 and IFN-γ in CD4+ T cells and the levels of IFN-γ in CD8+ T cells. Finally, intramuscular administration of OVA and Compound 22 significantly inhibited the growth of OVA-expressing tumors. Collectively, CCR4 plays a pivotal role in Treg cell recruitment to the muscle tissue, and intramuscular administration of CCR4 antagonists may be a promising approach for enhancing vaccine efficacy.

Soybean oil containing ginseng saponins as adjuvants promotes production of cytokines and enhances immune responses to foot-and-mouth disease vaccine.

In the present study, the adjuvant effect of soybean oil containing ginseng root saponins (SO-GS-R) on the immune response to foot-and-mouth disease vaccine (FMDV) in mice was investigated. When immunized with FMDV antigen emulsified in an SO-GS-R formulation, mice generated remarkably higher serum antibody and cytokine responses than mice immunized with FMDV antigen alone. To elucidate the mechanisms underlying the adjuvant effect of SO-GS-R, we measured cytokines in serum and muscle tissue after intramuscular injection of SO-GS-R. The results showed that injection of SO-GS-R significantly increased the levels of IL-1ß, IL-5, IL-6, G-CSF, KC, MCP-1, MIP-1α, and MIP-1ß in both serum and muscle. These results suggested that SO-GS-R recruits neutrophils, eosinophils, T cells and macrophages, causing immune cell recruitment at the injection site, driving antigen-presenting cells to actively participate in the onset of immunity, and amplifying the immune responses. Considering its adjuvant activity and plant-derived properties, SO-GS-R should be further studied for its adjuvant effect on vaccines used in food animals.

Long-term regulation of local cytokine production following immunization in mice.

Vaccines based on pathogen components require adjuvants to enhance the antigen-specific adaptive immune response. Intramuscular injection of adjuvanted-vaccines induces inflammatory cytokines and inflammatory nodules at the injection site within 48 hr after injection (Vaccine 2014; 32: 3393-401). In the present study, long-term regulation of cytokine production was investigated at 3, 6, 24, and 48 hr, 5 and 7 days, and 2 and 4 weeks after immunization with human papilloma virus (HPV), diphtheria and tetanus toxoids combined with acellular pertussis (DTaP), Haemophilus influenza type B (Hib), and pneumococcal conjugated (PCV) vaccines in mouse models. The second dose was given 4 weeks later, and cytokine profiles were investigated 2, 5, and 7 days after re-immunization. IL-1ß, IL-6, granulocyte-colony stimulating factor (G-CSF), and MCP-1 were produced from 3 hr and peaked at 48 hr after immunization with Cervarix in mice. IL-4, MCP-1, and TNF-α peaked at 5 or 7 days after immunization with Gardasil. These cytokines decreased 7 days after immunization with Cervarix and Gardasil. After the second dose, similar responses were observed. Both vaccines induced neutrophil extracellular traps (NET) in inflammatory nodules. The peak amount of IL-1ß, IL-6, G-CSF, and MCP-1 was observed on day 5 of immunization and that of IL-4 on days 5-7 of immunization with DTaP, but no increase in IL-6 and G-CSF was observed after re-immunization. A similar response was noted after immunization with PCV13. An inflammatory response is essential for the development of adaptive immunity through the production of inflammatory cytokines.

Drosophila muscles regulate the immune response against wasp infection via carbohydrate metabolism.

We recently found that JAK/STAT signaling in skeletal muscles is important for the immune response of Drosophila larvae against wasp infection, but it was not clear how muscles could affect the immune response. Here we show that insulin signaling is required in muscles, but not in fat body or hemocytes, during larval development for an efficient encapsulation response and for the formation of lamellocytes. This effect requires TOR signaling. We show that muscle tissue affects the immune response by acting as a master regulator of carbohydrate metabolism in the infected animal, via JAK/STAT and insulin signaling in the muscles, and that there is indirect positive feedback between JAK/STAT and insulin signaling in the muscles. Specifically, stimulation of JAK/STAT signaling in the muscles can rescue the deficient immune response when insulin signaling is suppressed. Our results shed new light on the interaction between metabolism, immunity, and tissue communication.

Combined skin and muscle vaccination differentially impact the quality of effector T cell functions: the CUTHIVAC-001 randomized trial.

Targeting of different tissues via transcutaneous (TC), intradermal (ID) and intramuscular (IM) injection has the potential to tailor the immune response to DNA vaccination. In this Phase I randomised controlled clinical trial in HIV-1 negative volunteers we investigate whether the site and mode of DNA vaccination influences the quality of the cellular immune responses. We adopted a strategy of concurrent immunization combining IM injection with either ID or TC administration. As a third arm we assessed the response to IM injection administered with electroporation (EP). The DNA plasmid encoded a MultiHIV B clade fusion protein designed to induce cellular immunity. The vaccine and regimens were well tolerated. We observed differential shaping of vaccine induced virus-specific CD4 + and CD8 + cell-mediated immune responses. DNA given by IM + EP promoted strong IFN-γ responses and potent viral inhibition. ID + IM without EP resulted in a similar pattern of response but of lower magnitude. By contrast TC + IM (without EP) shifted responses towards a more Th-17 dominated phenotype, associated with mucosal and epidermal protection. Whilst preliminary, these results offer new perspectives for differential shaping of desired cellular immunity required to fight the wide range of complex and diverse infectious diseases and cancers.

Autoimmune paraneoplastic syndromes associated to lung cancer: A systematic review of the literature Part 4: Neurological paraneoplastic syndromes, involving the peripheral nervous system and the neuromuscular junction and muscles.

The development of new immune treatment in oncology and particularly for lung cancer may induce new complications, particularly activation or reactivation of auto-immune diseases. In this context, a systematic review on the auto-immune paraneoplastic syndromes that can complicate lung cancer appears useful. This article is the fourth of a series of five and deals mainly with neurological paraneoplastic syndromes involving the peripheral nervous system and the neuromuscular junction and muscles.

Autoimmune paraneoplastic syndromes associated to lung cancer: A systematic review of the literature: Part 5: Neurological auto-antibodies, discussion, flow chart, conclusions.

The development of new immune treatment in oncology and particularly for lung cancer may induce new complications, particularly activation or reactivation of auto-immune diseases. In this context, a systematic review on the auto-immune paraneoplastic syndromes that can complicate lung cancer appears useful. This article is the last of a series of five and deals mainly with onconeural antibodies involved in neurological paraneoplastic syndromes and provides the final discussion.

Diagnosis and Management of Immune-Mediated Myopathies.

Immune-mediated myopathies (IMMs) are a heterogeneous group of acquired muscle disorders characterized by muscle weakness, elevated creatine kinase levels, and myopathic electromyographic findings. Most IMMs feature the presence of inflammatory infiltrates in muscle. However, the inflammatory exudate may be absent. Indeed, necrotizing autoimmune myopathy (NAM), also called immune-mediated necrotizing myopathy, is characterized by a necrotizing pathologic process with no or minimal inflammation in muscle. The recent discovery of antibodies associated with specific subtypes of autoimmune myopathies has played a major role in characterizing these diseases. Although diagnostic criteria and classification of IMMs currently are under revision, on the basis of the clinical and muscle histopathologic findings, IMMs can be differentiated as NAM, inclusion body myositis (IBM), dermatomyositis, polymyositis, and nonspecific myositis. Because of recent developments in the field of NAM and IBM and the controversies around polymyositis, this review will focus on NAM, IBM, and dermatomyositis.

STAT3 promotes IFNγ/TNFα-induced muscle wasting in an NF-κB-dependent and IL-6-independent manner.

Cachexia is a debilitating syndrome characterized by involuntary muscle wasting that is triggered at the late stage of many cancers. While the multifactorial nature of this syndrome and the implication of cytokines such as IL-6, IFNγ, and TNFα is well established, we still do not know how various effector pathways collaborate together to trigger muscle atrophy. Here, we show that IFNγ/TNFα promotes the phosphorylation of STAT3 on Y705 residue in the cytoplasm of muscle fibers by activating JAK kinases. Unexpectedly, this effect occurs both in vitro and in vivo independently of IL-6, which is considered as one of the main triggers of STAT3-mediated muscle wasting. pY-STAT3 forms a complex with NF-κB that is rapidly imported to the nucleus where it is recruited to the promoter of the iNos gene to activate the iNOS/NO pathway, a well-known downstream effector of IFNγ/TNFα-induced muscle loss. Together, these findings show that STAT3 and NF-κB respond to the same upstream signal and cooperate to promote the expression of pro-cachectic genes, the identification of which could provide effective targets to combat this deadly syndrome.

Assessment of immune status of yellowfin seabream (Acanthopagrus latus) during short term exposure to phenanthrene.

The aim of the present investigation was to assess the immune status in yellowfin seabream (Acanthopagrus latus) exposed to different concentrations of phenanthrene (Phe) for 14days. In addition, the Phe accumulation in the fish muscle was measured during the experiment. Fish were injected with different concentrations (0, 2, 20 and 40mg/kg) of Phe and samples were taken from tissue and blood of fish 1, 4, 7 and 14days after injection. Exposure of fish to Phe caused a significant decrease in white blood cells, C3 and C4 levels, lysosomal membrane stability, lysozyme activity after 4days and antibacterial activity after 7days of the experiment. In contrast, cortisol level significantly increased after 4days. The concentration of Phe in fish muscle increased rapidly after 4days. The main tissue changes observed in the head kidney including increase in melanomacrophage centers (MMCs), empty spaces between cells and hemorrhage. The degree of tissue changes ranged from normal to moderate in Phe-treated fish. The size and number of MMCs in treated fish were significantly higher than control. In conclusion, Phe toxicity in yellowfin seabream can induce increased cortisol level, tissue changes and immune suppression.

The host defense peptide LL-37 a possible inducer of the type I interferon system in patients with polymyositis and dermatomyositis.

The type I interferon (IFN) system has recently been suggested to play important and essential roles in the pathogenesis of myositis. However, a clarification of how type I IFNs could function as triggering factor(s) in the pathogenesis of myositis has yet failed. Through activation of the type I IFN system, the host defense peptide LL-37 carries numerous immunomodulatory properties and is implicated in the pathogenesis of several other autoimmune diseases, including systemic lupus erythematosus (SLE). The expression of LL-37 can be regulated by various endogenous factors including the active form of vitamin D (25(OH)D3). The aim of this study was to explore a potential role of LL-37 in relation to the type I IFN system in patients with polymyositis (PM) and dermatomyositis (DM) and to compare these with SLE patients and healthy controls. We investigated muscle (3 PM, 5 DM) and symptomatic (5 DM) and non-symptomatic (3 PM, 3 DM) skin biopsies from patients with short disease duration and muscle biopsies (3 PM, 1 DM) from patients with long disease duration. Six SLE patients with symptomatic and non-symptomatic skin and five muscle and six skin biopsies from healthy individuals served as controls. Tissue specimens were immunohistochemically stained for LL-37, neutrophils (CD66b), plasmacytoid dendritic cells (BDCA-2), myxovirus resistance protein A (MxA), and macrophages (CD68, CD163). In addition, LL-37 and CD66b double staining was also performed. Serum levels of 25(OH)D3 were investigated in PM and DM patients with short disease duration (3 PM, 5 DM) and in 40 healthy controls. We found that the expression of LL-37, BDCA-2 (the major producer of type I IFNs), MxA (an interferon-inducible protein), and macrophages were higher in muscle tissue of PM and DM patients compared to healthy controls. The LL-37 expression was mainly derived from neutrophils. Neutrophils were increased in both symptomatic and non-symptomatic skin of myositis and SLE patients and BDCA-2 was increased in symptomatic DM skin when compared to healthy controls. Moreover, the expression of MxA in symptomatic and non-symptomatic skin of SLE patients was higher when compared to both myositis patients and healthy controls. There was no difference in the expression of LL-37 in skin of myositis and SLE patients compared to healthy controls. All PM and DM patients with a short disease duration had low 25(OH)D3 levels compared to healthy controls. In conclusion, the present study supports our hypothesis that LL-37 may activate type I IFNs, which could initiate and perpetuate an inflammatory process. The prolonged exposure of the immune system to type I IFNs may eventually break tolerance and lead to autoimmune myositis.

Muscle wound healing in rainbow trout (Oncorhynchus mykiss).

We followed the progression of healing of deep excisional biopsy punch wounds over the course of 365 days in rainbow trout (Oncorhynchus mykiss) by monitoring visual wound healing and gene expression in the healing muscle at regular intervals (1, 3, 7, 14, 38 and 100 days post-wounding). In addition, we performed muscle texture analysis one year after wound infliction. The selected genes have all previously been investigated in relation to vertebrate wound healing, but only few specifically in fish. The selected genes were interleukin (IL)-1ß, IL-6, transforming growth factor (TGF)-ß1 and -ß3, matrix metalloproteinase (MMP) -9 and -13, inducible nitric oxide synthase (iNOS), fibronectin (FN), tenascin-C (TN-C), prolyl 4-hydroxylase α1-chain (P4Hα1), lysyl oxidase (LOX), collagen type I α1-chain (ColIα1), CD41 and CD163. Wound healing progressed slowly in the presented study, which is at least partially due to the low temperature of about 8.5 °C during the first 100 days. The inflammation phase lasted more than 14 days, and the genes relating to production and remodeling of new extracellular matrix (ECM) exhibited a delayed but prolonged upregulation starting 1-2 weeks post-wounding and lasting until at least 100 days post-wounding. The gene expression patterns and histology reveal limited capacity for muscle regeneration in rainbow trout, and muscle texture analyses one year after wound infliction confirm that wounds heal with fibrosis. At 100 dpw epidermis had fully regenerated, and dermis partially regenerated. Scales had not regenerated even after one year. CD163 is a marker of "wound healing"-type M2c macrophages in mammals. M2 macrophage markers are as yet poorly described in fish. The pattern of CD163 expression in the present study is consistent with the expected timing of presence of M2c macrophages in the wound. CD163 may thus potentially prove a valuable marker of M2 macrophages - or a subset hereof - in fish. We subjected a group of fish to bathing in an immunomodulatory ß-glucan product during wound healing, but found this to have very limited effect on wound healing in contrast to a previously published study on common carp.

Inflammatory myopathy: diagnosis and clinical course, specific clinical scenarios and new complementary tools.

Idiopathic inflammatory myopathies are a heterogeneous group of rare autoimmune diseases characterized by symmetric proximal muscle weakness and inflammatory infiltrates on muscle biopsy. A meticulously collected combination of clinical, serological, and pathological data is essential to correctly diagnose and classify myositis patients, often a considerable challenge for clinicians. This article provides a comprehensive overview of the most useful tools for the diagnosis and follow-up of patients with myositis. Capillaroscopy, serological biomarkers (particularly the autoantibody profile) and imaging techniques, such as muscle magnetic resonance and chest ultrasound, are of great aid in diagnosing, classifying and managing these patients. Relevant clinical scenarios, such as interstitial lung disease, associated cancer and pregnancy are also addressed in this review. Myositis registries, identification of new autoantibodies, and genetic studies will enhance our understanding of the pathogenesis of these conditions and help to define new diagnostic and therapeutic approaches.

A manganese superoxide dismutase (MnSOD) from ark shell, Scapharca broughtonii: Molecular characterization, expression and immune activity analysis.

Manganese superoxide dismutase (MnSOD) is one of the key members of the antioxidant defense enzyme family, however, data regarding to the immune function of MnSOD in mollusks still remain limited now. In this study, a full-length MnSOD cDNA was identified by rapid amplification of cDNA ends (RACE) method from cDNA library of ark shell Scapharca broughtonii (termed SbMnSOD). The cDNA contained an open reading frame (ORF) of 696 bp which encoded a polypeptide of 232 amino acids, a 5'-UTR with length of 32 bp and a 3'-UTR of 275 bp. Four putative amino acid residues (His-57, His-105, Asp-190 and His-194) responsible for manganese coordination were located in the most highly conserved regions of SbMnSOD and the signature sequence (DVWEHAYY) also existed in SbMnSOD. The deduced amino acid sequence of SbMnSOD shared high homology to MnSOD from other species. All those data revealed that the SbMnSOD was a novel member of the MnSOD family. The mRNA expression profiles of SbMnSOD in tissues of foot, gill, mantle, adductor muscle, hemocytes and hepatopancreas analyzed by quantitative real-time PCR (qRT-PCR) suggested the mRNA transcripts of SbMnSOD distributed in all the examined tissues. Importantly, Vibrio anguillarum challenge resulted in the increased expression of SbMnSOD mRNA with a regular change trend in all examined tissues, indicating SbMnSOD actively participated in the immune response process. What's more, further analysis on the antibacterial activity of the recombinant SbMnSOD showed that the fusion protein could remarkably inhibit growth of both Gram-positive and Gram-negative bacteria. The present results clearly suggested that SbMnSOD was an acute phase protein involved in the immune reaction in S. broughtonii.