Targeting GM-CSF in inflammatory diseases

Profiling migration of human monocytes in response to chemotactic and barotactic guidance cues

Monocytes are critical to innate immunity, participating in chemotaxis during tissue injury, infection, and inflammatory conditions. However, the migration dynamics of human monocytes under different guidance cues are not well characterized. Here, we developed a microfluidic device to profile the migration characteristics of human monocytes under chemotactic and barotactic guidance cues while also assessing the effects of age and cytokine stimulation. Human monocytes preferentially migrated toward the CCL2 gradient through confined microchannels, regardless of donor age and migration pathway. Stimulation with interferon (IFN)-γ, but not granulocyte-macrophage colony-stimulating factor (GM-CSF), disrupted monocyte navigation through complex paths and decreased monocyte CCL2 chemotaxis, velocity, and CCR2 expression. Additionally, monocytes exhibited a bias toward low-hydraulic-resistance pathways in asymmetric environments, which remained consistent across donor ages, cytokine stimulation, and chemoattractants. This microfluidic system provides insights into the unique migratory behaviors of human monocytes and is a valuable tool for studying peripheral immune cell migration in health and disease.

Effector and regulatory B-cell imbalance in systemic sclerosis: cooperation or competition?

B cells play a central role in the pathogenesis of systemic sclerosis (SSc). Most B-cell studies have focused on their pathological role as antibody producers. However, in addition to immunoglobulin secretion, these cells have a wide range of functions in the immune response, including antigen presentation to T cells and cytokine production. Importantly, not all B-cell subsets promote the immune response. Regulatory B cells (Bregs) attenuate inflammation and contribute to the maintenance of immune tolerance. However, effector B cells (Beffs) positively modulate the immune response through the production of various cytokines. In SSc, Bregs are insufficient and/or dysfunctional. B-cell-targeting biologics have been trialled with promising results in the treatment of SSc. These therapies can affect Bregs or Beffs, which can potentially limit their long-term efficacy. Future strategies might involve the modulation of effector B cells in combination with the stimulation of regulatory subsets. Additionally, the monitoring of individual B-cell subsets in patients may lead to the discovery of novel biomarkers that could help predict disease relapse or progression. The purpose of this review is to summarize the relevant literatures and explain how Bregs and Beffs jointly participate in the pathogenesis of SSc.

Extensive study of CCN4, VCAM-1, MMP-3, and GM-CSF as reliable markers for disease activity in rheumatoid arthritis

Background

The involvement of Wnt-1-induced secreted protein-1 (WISP1/CCN4) in several inflammatory reaction has recently been proposed. Nevertheless, this protein's involvement in rheumatoid arthritis (RA) remains debated. Associations between poorly diagnosed RA and several classical markers derived from demography and biochemistry have been reported.

Aim

We sought to investigate the reliability and effectiveness of serum concentrations of CCN4, vascular cell adhesion molecule-1 (VCAM-1), matrix melloprotenase-3 (MMP-3), and granulocyte-macrophage colony-stimulating factor (GM-CSF) in monitoring and predicting RA and bone damage, and their correlation with RA disease course.

Methods

The study analyzed 128 patients with RA, comprising 68 newly diagnosed and 60 previously diagnosed patients, as well as 60 controls. Biomarker levels were measured with enzyme linked immuno-sorbent assays. Routine laboratory parameters such as serological, clinical, biochemical, and hematological parameters were additionally measured. Demography, anthropometry, and clinical symptom data were collected through interviews and a questionnaire. The joint disease activity score 28 (DAS28) was used to determine disease activity.

Results

Concentrations of four biomarkers were significantly higher in the RA group than the healthy controls. Elevated biomarker concentrations were also observed in patients with high, rather than moderate or low, DAS28-ESR activity status, except for monocyte count, hematocrit (%), and urea level. Furthermore, CCN4 level positively correlated with VCAM-1, MMP-3, and GM-CSF levels, DA-S28-CRP and DAS28-ESR. The levels of three predictive markers, CCN4, VCAM-1, and MMP-3, were elevated in non-treated patients, whereas GM-CSF level showed no difference. The highest area under the curve was 73.3% for CCN4, with 93.3% sensitivity and 64.7% specificity.

Conclusion

Our data suggest that CCN4 can be reliably used to indicate activity and therapeutic response associated with RA, thus facilitating earlier RA diagnosis.

Liposomal curcumin inhibits cigarette smoke induced senescence and inflammation in human bronchial epithelial cells

Curcumin, the principal curcuminoid of turmeric (Curcuma longa extract), is very well known for its multiple biological therapeutic activities, particularly its anti-inflammatory and antioxidant potential. However, due to its low water solubility, it exhibits poor bioavailability. In order to overcome this problem, in the current study, we have employed liposomal technology to encapsulate curcumin with the aim of enhancing its therapeutic efficacy. The curcumin-loaded liposomes (PlexoZome®) were tested on a cigarette smoke extract-induced Chronic Obstructive Pulmonary Disease (COPD) in vitro model using minimally immortalized human bronchial epithelial cells (BCiNS1.1). The anti-senescence and anti-inflammatory properties of PlexoZome® were explored. 5 µM PlexoZome® curcumin demonstrated anti-senescent activity by decrease in X-gal positive cells, and reduction in the expression of p16 and p21 in immunofluorescence staining. Moreover, PlexoZome® curcumin also demonstrated a reduction in proteins related to senescence (osteopontin, FGF basic and uPAR) and inflammation (GM-CSF, EGF and ST2). Overall, the results clearly demonstrate the therapeutic potential of curcumin encapsulated liposomes in managing CSE induced COPD, providing a new direction to respiratory clinics.

Serum GM-CSF level is a predictor of treatment response to tocilizumab in rheumatoid arthritis patients: a prospective observational cohort study

BACKGROUND

The aim of this prospective observational cohort study was to unveil the predictors of treatment response to tocilizumab (TCZ) therapy in rheumatoid arthritis (RA) patients, in terms of clinical characteristics and serum proinflammatory cytokines, especially to explore the predictive value of granulocyte macrophage-colony stimulating factor (GM-CSF).

METHODS

Active adult RA patients with inadequate response to MTX intending to receive TCZ therapy were recruited prospectively in the study. A total of 174 severe RA patients were included for the identification of the associations between treatment response and the following characteristic features: demographics, medications, disease activity, serum proinflammatory cytokines and so on.

RESULTS

Disease duration (OR = 0.996), tender joint count (TJC)/68 (OR = 0.943), neutrophil ratio (W4/baseline) (OR = 0.224), the high level of GM-CSF > 5 ng/ml (OR = 0.414) at baseline were the independent adverse predictors of good response assessed by clinical disease activity index (CDAI) at week 24 (W24) for TCZ therapy in RA patients. Moreover, DAS28-ESR (OR = 2.951, P = 0.002) and the high level of GM-CSF > 10 ng/ml at baseline (OR = 5.419, P = 0.002) were independent predictors of poor response, but not the high level of GM-CSF > 5 ng/ml (OR = 2.713, P = 0.054). The patients in the high GM-CSF group had significantly higher DAS28-ESR and serum levels of cytokines (IL-17A, IL-1β, IL-6, TNF-α) at baseline, as well as significantly higher rate of non-good response (62.8% vs. 39.4%, P = 0.010) and poor response (27.9% vs. 9.1%, P = 0.004) than the low GM-CSF group at W24. In addition, poor responders had significantly higher levels of GM-CSF with concomitant increase in the serum levels of IL-17A and IL-1β at baseline than those in moderate and good response groups, while serum levels of IL-6 and TNF-α at baseline were not significantly different in three response groups.

CONCLUSION

The high levels of GM-CSF (> 5 ng/ml and > 10 ng/ml) at baseline were the independent predictors of non-good response and poor response to TCZ at W24 respectively. The high level of GM-CSF at baseline is a marker of high disease activity and a predictor of poor response to TCZ in severe RA patients, which may facilitate the development of individualized treatment strategies for refractory RA.

Integrated Analysis of Transcriptome Profiles and lncRNA-miRNA-mRNA Competing Endogenous RNA Regulatory Network to Identify Biological Functional Effects of Genes and Pathways Associated with Johne's Disease in Dairy Cattle

Paratuberculosis or Johne's disease (JD), a chronic granulomatous gastroenteritis caused by Mycobacterium avium subsp. paratuberculosis (MAP), causes huge economic losses and reduces animal welfare in dairy cattle herds worldwide. At present, molecular mechanisms and biological functions involved in immune responses to MAP infection of dairy cattle are not clearly understood. Our purpose was to integrate transcriptomic profiles and competing endogenous RNA (ceRNA) network analyses to identify key messenger RNAs (mRNAs) and regulatory RNAs involved in molecular regulation of peripheral blood mononuclear cells (PBMCs) for MAP infection in dairy cattle. In total, 28 lncRNAs, 42 miRNAs, and 370 mRNAs were identified by integrating gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. In this regard, we identified 21 hub genes (CCL20, CCL5, CD40, CSF2, CXCL8, EIF2AK2, FOS, IL10, IL17A, IL1A, IL1B, IRF1, MX2, NFKB1, NFKBIA, PTGS2, SOCS3, TLR4, TNF, TNFAIP3, and VCAM1) involved in MAP infection. Furthermore, eight candidate subnets with eight lncRNAs, 29 miRNAs, and 237 mRNAs were detected through clustering analyses, whereas GO enrichment analysis of identified RNAs revealed 510, 22, and 11 significantly enriched GO terms related to MAP infection in biological process, molecular function, and cellular component categories, respectively. The main metabolic-signaling pathways related to MAP infection that were enriched included the immune system process, defense response, response to cytokine, leukocyte migration, regulation of T cell activation, defense response to bacterium, NOD-like receptor, B cell receptor, TNF, NF-kappa B, IL-17, and T cell receptor signaling pathways. Contributions of transcriptome profiles from MAP-positive and MAP-negative sample groups plus a ceRNA regulatory network underlying phenotypic differences in the intensity of pathogenicity of JD provided novel insights into molecular mechanisms associated with immune system responses to MAP infection in dairy cattle.

Increased TGFβ1, VEGF and IFN-γ in the Sputum of Severe Asthma Patients With Bronchiectasis

BACKGROUND

Bronchiectasis is one of the most common comorbidities in severe asthma. However, the mechanisms by which asthma promotes the development and progress of this condition are not well defined. This study aimed to analyze the inflammatory phenotypes and quantify the expression of proinflammatory and remodeling cytokines in asthma patients with and without bronchiectasis.

METHODS

The study sample comprised individuals with severe asthma and bronchiectasis (group AB, n=55) and a control population of individuals with severe asthma without bronchiectasis (group AC, n=45). Induced sputum samples were obtained and cell types determined by differential cell count. Proinflammatory and bronchial remodeling cytokines (IL-8, neutrophilic elastase, TGFβ1, VEGF, IFN-γ, TNF-α, and GM-CSF) were analyzed by immunoassay in sputum supernatant.

RESULTS

Neutrophilic inflammation was the primary phenotype in both asthma groups. Higher levels of TGFβ1, VEGF and IFN-γ were observed in asthma patients with bronchiectasis (group AB) than in controls (group AC) (15 vs 24pg/ml, p=0.014; 183 vs 272pg/ml, p=0.048; 0.85 vs 19pg/ml, p<0.001, respectively). Granulocyte-macrophage colony-stimulating factor (GM-CSF) levels were significantly lower in the AB group than in the AC group (1.2 vs 4.4pg/ml, p<0.001). IL-8, neutrophil elastase and TNF-α did not present significant differences between the groups.

CONCLUSIONS

Raised levels of TGFβ1 and VEGF cytokines may indicate airway remodeling activation in asthma patients with bronchiectasis. The type of inflammation in asthma patients did not differ according to the presence or absence of bronchiectasis.

Bound polyphenols in insoluble dietary fiber of navel orange peel modulate LPS-induced intestinal-like co-culture inflammation through CSF2-mediated NF-κB/JAK-STAT pathway

Our laboratory previously extracted bound polyphenols (BPP) in insoluble dietary fiber from navel orange peel (NOP-IDF), and the aim of this study was to investigate the anti-inflammatory activity and potential molecular mechanisms of BPP by establishing an LPS-induced intestinal-like Caco-2/RAW264.7 co-culture inflammation model. The results demonstrated that BPP reduced the expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS), as well as the production of pro-inflammatory cytokines, nitric oxide (NO), and reactive oxidative species (ROS) during the inflammatory damage process. Furthermore, BPP alleviated the lipopolysaccharides (LPS)-induced intestinal barrier damage by attenuating the decrease in trans-epithelial electrical resistance (TEER), diamine oxidase (DAO) activity, and intestinal alkaline phosphatase (IAP) activity, as well as the downregulation of ZO-1, Occludin, and Claudin-1 protein expression levels. RNA-seq results on RAW264.7 cells in the co-culture model showed that the NF-κB and JAK-STAT pathways belonged to the most significantly affected signaling pathways in the KEGG analysis, and western blot confirmed that they are essential for the role of BPP in intestinal inflammation. Additionally, overexpression of the granulocyte-macrophage colony-stimulating factor (CSF2) gene triggered abnormal activation of the NF-κB and JAK-STAT pathways and high-level expression of inflammatory factors, while BPP effectively improved this phenomenon. The above results suggested that BPP could inhibit intestinal inflammatory injury and protect intestinal barrier integrity through CSF2-mediated NF-κB and JAK-STAT pathways.

Indications of pro-inflammatory cytokines in laparoscopic and open liver resection for early-stage hepatocellular carcinoma

BACKGROUND

Our clinical practice of laparoscopic liver resection (LLR) had achieved better short-term and long-term benefits for patients with hepatocellular carcinoma (HCC) over open liver resection (OLR), but the underlying mechanisms are not clear. This study was to find out whether systemic inflammation plays an important role.

METHODS

A total of 103 patients with early-stage HCC under liver resection were enrolled (LLR group, n = 53; OLR group, n = 50). The expression of 9 inflammatory cytokines in patients at preoperation, postoperative day 1 (POD1) and POD7 was quantified by Luminex Multiplex assay. The relationships of the cytokines and the postoperative outcomes were compared between LLR and OLR.

RESULTS

Seven of the circulating cytokines were found to be significantly upregulated on POD1 after LLR or OLR compared to their preoperative levels. Compared to OLR, the POD1 levels of granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-6 (IL-6), IL-8, and monocyte chemoattractant protein-1 (MCP-1) in the LLR group were significantly lower. Higher POD1 levels of these cytokines were significantly correlated with longer operative time and higher volume of blood loss during operation. The levels of these cytokines were positively associated with postoperative liver injury, and the length of hospital stay. Importantly, a high level of IL-6 at POD1 was a risk factor for HCC recurrence and poor disease-free survival after liver resection.

CONCLUSIONS

Significantly lower level of GM-CSF, IL-6, IL-8, and MCP-1 after liver resection represented a milder systemic inflammation which might be an important mechanism to offer better short-term and long-term outcomes in LLR over OLR.

Inhaled Macrophage Apoptotic Bodies-Engineered Microparticle Enabling Construction of Pro-Regenerative Microenvironment to Fight Hypoxic Lung Injury in Mice

Oxygen therapy cannot rescue local lung hypoxia in patients with severe respiratory failure. Here, an inhalable platform is reported for overcoming the aberrant hypoxia-induced immune changes and alveolar damage using camouflaged poly(lactic-co-glycolic) acid (PLGA) microparticles with macrophage apoptotic body membrane (cMAB). cMABs are preloaded with mitochondria-targeting superoxide dismutase/catalase nanocomplexes (NCs) and modified with pathology-responsive macrophage growth factor colony-stimulating factor (CSF) chains, which form a core-shell platform called C-cMAB/NC with efficient deposition in deeper alveoli and high affinity to alveolar epithelial cells (AECs) after CSF chains are cleaved by matrix metalloproteinase 9. Therefore, NCs can be effectively transported into mitochondria to inhibit inflammasome-mediated AECs damage in mouse models of hypoxic acute lung injury. Additionally, the at-site CSF release is sufficient to rescue circulating monocytes and macrophages and alter their phenotypes, maximizing synergetic effects of NCs on creating a pro-regenerative microenvironment that enables resolution of lung injury and inflammation. This inhalable platform may have applications to numerous inflammatory lung diseases.

Impact of maternal immune activation and sex on placental and fetal brain cytokine and gene expression profiles in a preclinical model of neurodevelopmental disorders

Maternal inflammation during gestation is associated with a later diagnosis of neurodevelopmental disorders including autism spectrum disorder (ASD). However, the specific impact of maternal immune activation (MIA) on placental and fetal brain development remains insufficiently understood. This study aimed to investigate the effects of MIA by analyzing placental and brain tissues obtained from the offspring of pregnant C57BL/6 dams exposed to polyinosinic: polycytidylic acid (poly I: C) on embryonic day 12.5. Cytokine and mRNA content in the placenta and brain tissues were assessed using multiplex cytokine assays and bulk-RNA sequencing on embryonic day 17.5. In the placenta, male MIA offspring exhibited higher levels of GM-CSF, IL-6, TNFα, and LT-α, but there were no differences in female MIA offspring. Furthermore, differentially expressed genes (DEG) in the placental tissues of MIA offspring were found to be enriched in processes related to synaptic vesicles and neuronal development. Placental mRNA from male and female MIA offspring were both enriched in synaptic and neuronal development terms, whereas females were also enriched for terms related to excitatory and inhibitory signaling. In the fetal brain of MIA offspring, increased levels of IL-28B and IL-25 were observed with male MIA offspring and increased levels of LT-α were observed in the female offspring. Notably, we identified few stable MIA fetal brain DEG, with no male specific difference whereas females had DEG related to immune cytokine signaling. Overall, these findings support the hypothesis that MIA contributes to the sex- specific abnormalities observed in ASD, possibly through altered neuron developed from exposure to inflammatory cytokines. Future research should aim to investigate how interactions between the placenta and fetal brain contribute to altered neuronal development in the context of MIA.

GM-CSF Promotes the Development of Dysfunctional Vascular Networks in Moyamoya Disease

Moyamoya disease (MMD) is a chronic occlusive cerebrovascular disease with the development of a network of abnormal vessels. Immune inflammation is associated with the occurrence and development of MMD. However, the mechanisms underlying the formation of the abnormal vascular network remain unclear. Twenty-eight patients with MMD, 26 ischemic stroke patients, and 26 unrelated healthy volunteers were enrolled in this study The data showed that the levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) were higher in MMD patients than in healthy controls (P <0.01), and GM-CSF was mainly from Th1 and Th17 cells in MMD. We found that increased GM-CSF drove monocytes to secrete a series of cytokines associated with angiogenesis, inflammation, and chemotaxis. In summary, our findings demonstrate for the first time the important involvement of GM-CSF in MMD and that GM-CSF is an important factor in the formation of abnormal vascular networks in MMD.

Macrophage re-programming by JAK inhibitors relies on MAFB

Monocyte-derived macrophages play a key pathogenic role in inflammatory diseases. In the case of rheumatoid arthritis (RA), the presence of specific synovial tissue-infiltrating macrophage subsets is associated with either active disease or inflammation resolution. JAK inhibitors (JAKi) are the first targeted synthetic disease-modifying antirheumatic drugs (tsDMARD) approved for treatment of RA with comparable efficacy to biologics. However, the effects of JAKi on macrophage specification and differentiation are currently unknown. We have analyzed the transcriptional and functional effects of JAKi on human peripheral blood monocyte subsets from RA patients and on the differentiation of monocyte-derived macrophages promoted by granulocyte-macrophage colony-stimulating factor (GM-CSF), a factor that drives the development and pathogenesis of RA. We now report that JAKi Upadacitinib restores the balance of peripheral blood monocyte subsets in RA patients and skewed macrophages towards the acquisition of an anti-inflammatory transcriptional and functional profile in a dose-dependent manner. Upadacitinib-treated macrophages showed a strong positive enrichment of the genes that define synovial macrophages associated to homeostasis/inflammation resolution. Specifically, Upadacitinib-treated macrophages exhibited significantly elevated expression of MAFB and MAFB-regulated genes, elevated inhibitory phosphorylation of GSK3β, and higher phagocytic activity and showed an anti-inflammatory cytokine profile upon activation by pathogenic stimuli. These outcomes were also shared by macrophages exposed to other JAKi (baricitinib, tofacitinib), but not in the presence of the TYK2 inhibitor deucravacitinib. As a whole, our results indicate that JAKi promote macrophage re-programming towards the acquisition of a more anti-inflammatory/pro-resolution profile, an effect that correlates with the ability of JAKi to enhance MAFB expression.

Cytokines, Vascular Endothelial Growth Factors, and PlGF in Autoimmunity: Insights From Rheumatoid Arthritis to Multiple Sclerosis

In this review, we will explore the intricate roles of cytokines and vascular endothelial growth factors in autoimmune diseases (ADs), with a particular focus on rheumatoid arthritis (RA) and multiple sclerosis (MS). AD is characterized by self-destructive immune responses due to auto-reactive T lymphocytes and Abs. Among various types of ADs, RA and MS possess inflammation as a central role but in different sites of the patients. Other common aspects among these two ADs are their chronicity and relapsing-remitting symptoms requiring continuous management. First factor inducing these ADs are cytokines, such as IL-6, TNF-α, and IL-17, which play significant roles in the pathogenesis by contributing to inflammation, immune cell activation, and tissue damage. Secondly, vascular endothelial growth factors, including VEGF and angiopoietins, are crucial in promoting angiogenesis and inflammation in these two ADs. Finally, placental growth factor (PlGF), an emerging factor with bi-directional roles in angiogenesis and T cell differentiation, as we introduce as an "angio-lymphokine" is another key factor in ADs. Thus, while angiogenesis recruits more inflammatory cells into the peripheral sites, cytokines secreted by effector cells play critical roles in the pathogenesis of ADs. Various therapeutic interventions targeting these soluble molecules have shown promise in managing autoimmune pathogenic conditions. However, delicate interplay between cytokines, angiogenic factors, and PlGF has more to be studied when considering their complementary role in actual pathogenic conditions. Understanding the complex interactions among these factors provides valuable insights for the development of innovative therapies for RA and MS, offering hope for improved patient outcomes.

Inflammatory endotypes of adenoidal hypertrophy based on a cluster analysis of biomarkers

OBJECTIVE

To identify adenoid inflammatory endotypes based on inflammatory markers, match endotypes to phenotypes, and predict endotypes.

METHODS

This cross-sectional study included 72 children with adenoid hypertrophy. Thirteen inflammatory markers and total immunoglobulin E (TIgE) in adenoid tissue were analyzed using Luminex and enzyme-linked immunosorbent assay (ELISA) for performing cluster analysis. Correlation analysis was used to examine the characteristics of each cluster. Receiver operating characteristic (ROC) curve analysis was performed to screen for preoperative characteristic data with predictive value for adenoid inflammation endotype.

RESULTS

The patients were divided into four clusters. Cluster 1 exhibited non-type 2 signatures with low inflammatory marker concentrations, except for the highest expression of Th1-related cytokines. Cluster 2 showed a non-type 2 endotype with the highest concentration of interleukin (IL)-17A and IL-22. Cluster 3 exhibited moderate type 2 inflammation, with the highest concentration of neutrophil factors. Cluster 4 demonstrated significant type 2 inflammation and moderate neutrophil levels. The proportions of AR and serum TIgE levels increased from clusters 1 to 4, and there was a gradual increase in the prevalence of chronic sinusitis from low to high neutrophilic inflammation. The area under the ROC curve for serum TIgE was higher than those for combined or other separate preoperative characteristics for predicting non-type 2 and type 2 inflammation in the adenoid tissue.

CONCLUSIONS

The evaluation of cytokines in adenoid tissue revealed four endotypes. Serum TIgE level was an important indicator of the endotype of adenoid inflammation. Identification of adenoid inflammatory endotypes can facilitate targeted treatment decisions.

Encapsulated Streptococcus suis impairs optimal neutrophil functions which are not rescued by priming with colony-stimulating factors

The porcine pathogen and zoonotic agent Streptococcus suis induces an exacerbated inflammation in the infected hosts that leads to sepsis, meningitis, and sudden death. Several virulence factors were described for S. suis of which the capsular polysaccharide (CPS) conceals it from the immune system, and the suilysin exhibits cytotoxic activity. Although neutrophils are recruited rapidly upon S. suis infection, their microbicidal functions appear to be poorly activated against the bacteria. However, during disease, the inflammatory environment could promote neutrophil activation as mediators such as the granulocyte colony-stimulating factor granulocyte (G-CSF) and the granulocyte-macrophages colony-stimulating factor (GM-CSF) prime neutrophils and enhance their responsiveness to bacterial detection. Thus, we hypothesized that CPS and suilysin prevent an efficient activation of neutrophils by S. suis, but that G-CSF and GM-CSF rescue neutrophil activation, leading to S. suis elimination. We evaluated the functions of porcine neutrophils in vitro in response to S. suis and investigated the role of the CPS and suilysin on cell activation using isogenic mutants of the bacteria. We also studied the influence of G-CSF and GM-CSF on neutrophil response to S. suis by priming the cells with recombinant proteins. Our study confirmed that CPS prevents S. suis-induced activation of most neutrophil functions but participates in the release of neutrophil-extracellular traps (NETs). Priming with G-CSF did not influence cell activation, but GM-CSF strongly promote IL-8 release, indicating its involvement in immunomodulation. However, priming did not enhance microbicidal functions. Studying the interaction between S. suis and neutrophils-first responders in host defense-remains fundamental to understand the immunopathogenesis of the infection and to develop therapeutical strategies related to neutrophils' defense against this bacterium.

TRIM26 alleviates fatal immunopathology by regulating inflammatory neutrophil infiltration during Candida infection

Fungal infections have emerged as a major concern among immunocompromised patients, causing approximately 2 million deaths each year worldwide. However, the regulatory mechanisms underlying antifungal immunity remain elusive and require further investigation. The E3 ligase Trim26 belongs to the tripartite motif (Trim) protein family, which is involved in various biological processes, including cell proliferation, antiviral innate immunity, and inflammatory responses. Herein, we report that Trim26 exerts protective antifungal immune functions after fungal infection. Trim26-deficient mice are more susceptible to fungemia than their wild-type counterparts. Mechanistically, Trim26 restricts inflammatory neutrophils infiltration and limits proinflammatory cytokine production, which can attenuate kidney fungal load and renal damage during Candida infection. Trim26-deficient neutrophils showed higher proinflammatory cytokine expression and impaired fungicidal activity. We further demonstrated that excessive neutrophils infiltration in the kidney was because of the increased production of chemokines CXCL1 and CXCL2, which are mainly synthesized in the macrophages or dendritic cells of Trim26-deficient mice after Candida albicans infections. Together, our study findings unraveled the vital role of Trim26 in regulating antifungal immunity through the regulation of inflammatory neutrophils infiltration and proinflammatory cytokine and chemokine expression during candidiasis.

GM-CSF improves endometrial receptivity in a thin endometrium rat model by upregulating HOXA10

Endometrial receptivity is a prerequisite for the success of assisted reproduction. Patients with a consistently thin endometrium frequently fail to conceive, owing to low endometrial receptivity, and there are currently very few therapeutic options available. Our previous study demonstrated that intrauterine granulocyte-macrophage colony-stimulating factor (GM-CSF) administration resulted in a significant improvement in clinical pregnancy and implantation rates and was an effective means of increasing endometrial thickness on the day of embryo transfer in patients with thin endometrium. In order to explore the underlying process, an animal model with a thin endometrium was constructed, the homeobox A10 gene (HOXA10) was downregulated, and an inhibitor of the mitogen-activated protein kinase/extracellular signal-regulated kinase pathway (MAPK/ERK) was employed. Our findings strongly suggest a marked decrease in GM-CSF levels in the thin endometrial rat model, and the suppression of HOXA10 impeded the therapeutic efficacy of GM-CSF in this model. Moreover, we showed that GM-CSF significantly increases endometrial receptivity in the rat model and upregulates HOXA10 via the MAPK/ERK pathway. Our data provide new molecular insights into the mechanisms underlying formation of a thin endometrium and highlight a novel, potential clinical treatment strategy as well as directions for further research.

Comparative transcriptome analysis of SARS-CoV-2, SARS-CoV, MERS-CoV, and HCoV-229E identifying potential IFN/ISGs targets for inhibiting virus replication

Introduction

Since its outbreak in December 2019, SARS-CoV-2 has spread rapidly across the world, posing significant threats and challenges to global public health. SARS-CoV-2, together with SARS-CoV and MERS-CoV, is a highly pathogenic coronavirus that contributes to fatal pneumonia. Understanding the similarities and differences at the transcriptome level between SARS-CoV-2, SARS-CoV, as well as MERS-CoV is critical for developing effective strategies against these viruses.

Methods

In this article, we comparatively analyzed publicly available transcriptome data of human cell lines infected with highly pathogenic SARS-CoV-2, SARS-CoV, MERS-CoV, and lowly pathogenic HCoV-229E. The host gene expression profiles during human coronavirus (HCoV) infections were generated, and the pathways and biological functions involved in immune responses, antiviral efficacy, and organ damage were intensively elucidated.

Results

Our results indicated that SARS-CoV-2 induced a stronger immune response versus the other two highly pathogenic HCoVs. Specifically, SARS-CoV-2 induced robust type I and type III IFN responses, marked by higher upregulation of type I and type III IFNs, as well as numerous interferon-stimulated genes (ISGs). Further Ingenuity Pathway Analysis (IPA) revealed the important role of ISGs for impeding SARS-CoV-2 infection, and the interferon/ISGs could be potential targets for therapeutic interventions. Moreover, our results uncovered that SARS-CoV-2 infection was linked to an enhanced risk of multi-organ toxicity in contrast to the other two highly pathogenic HCoVs.

Discussion

These findings provided valuable insights into the pathogenic mechanism of SARS-CoV-2, which showed a similar pathological feature but a lower fatality rate compared to SARS-CoV and MERS-CoV.

Anti-GM-CSF otilimab versus sarilumab or placebo in patients with rheumatoid arthritis and inadequate response to targeted therapies: a phase III randomised trial (contRAst 3)

OBJECTIVES

To investigate the efficacy and safety of otilimab, an anti-granulocyte-macrophage colony-stimulating factor antibody, in patients with active rheumatoid arthritis and an inadequate response to conventional synthetic (cs) and biologic disease-modifying antirheumatic drugs (DMARDs) and/or Janus kinase inhibitors.

METHODS

ContRAst 3 was a 24-week, phase III, multicentre, randomised controlled trial. Patients received subcutaneous otilimab (90/150 mg once weekly), subcutaneous sarilumab (200 mg every 2 weeks) or placebo for 12 weeks, in addition to csDMARDs. Patients receiving placebo were switched to active interventions at week 12 and treatment continued to week 24. The primary end point was the proportion of patients achieving an American College of Rheumatology ≥20% response (ACR20) at week 12.

RESULTS

Overall, 549 patients received treatment. At week 12, there was no significant difference in the proportion of ACR20 responders with otilimab 90 mg and 150 mg versus placebo (45% (p=0.2868) and 51% (p=0.0596) vs 38%, respectively). There were no significant differences in Clinical Disease Activity Index, Health Assessment Questionnaire-Disability Index, pain Visual Analogue Scale or Functional Assessment of Chronic Illness Therapy-Fatigue scores with otilimab versus placebo at week 12. Sarilumab demonstrated superiority to otilimab in ACR20 response and secondary end points. The incidence of adverse or serious adverse events was similar across treatment groups.

CONCLUSIONS

Otilimab demonstrated an acceptable safety profile but failed to achieve the primary end point of ACR20 and improve secondary end points versus placebo or demonstrate non-inferiority to sarilumab in this patient population.

TRIAL REGISTRATION NUMBER

NCT04134728.

Granulocyte-macrophage colony-stimulating factor promotes endometrial repair after injury by regulating macrophages in mice

Intrauterine adhesion (IUA) caused by endometrial injury is a common cause of female infertility and is challenging to treat. Macrophages play a critical role in tissue repair and cyclical endometrial regeneration. Granulocyte-macrophage colony-stimulating factor (GM-CSF) has significant reparative and anti-fibrotic effects in various tissues. However, there is limited research on the role of GM-CSF in the repair of endometrial injury and the involvement of macrophages in GM-CSF-mediated endometrial repair. In this study, using a mouse model of endometrial scratching injury, we found that GM-CSF treatment accelerated the repair of endometrial injury and improved fertility. At the molecular level, we observed that GM-CSF can downregulate the transcript levels of tumor necrosis factor (TNF) in mouse bone marrow-derived macrophages (BMDMs) stimulated by lipopolysaccharide (LPS) and upregulate the expression of Arginase-1 (Arg-1) and mannose receptor C-type 1 (MRC1). Importantly, during the early and middle stages of injury, GM-CSF increased the proportion of M1-like, M2-like, and M1/M2 mixed macrophages, while in the late stage of injury, GM-CSF facilitated a decline in the number of M2-like macrophages. These findings suggest that GM-CSF may promote endometrial repair by recruiting macrophages and modulating the LPS-induced M1-like macrophages into a less inflammatory phenotype. These insights have the potential to contribute to the development of novel therapeutic approaches for the treatment of intrauterine adhesion and related infertility.

Interleukin-21 knockout reduces bone loss in ovariectomized mice by inhibiting osteoclastogenesis

Estrogen deficiency accelerates osteoporosis in elderly women. However, the role of IL-21 in postmenopausal osteoporosis remains unclear. Female wild-type (WT) C57BL/6 and IL-21 knockout (KO) mice were used for ovariectomy (OVX). Here, IL-21 levels were significantly increased in the serum and bone tissues of WT-OVX mice. The trabecular bone space of the femur was significantly increased, and the bone mass was reduced in OVX mice, accompanied by a significant decrease in the maximum load, energy absorption, and elastic modulus indices. In contrast, IL-21 knockout effectively alleviated the effects of OVX on bone mass. Serum TRACP-5b and receptor activator of nuclear factor kappa B ligand (RANKL) levels and osteoclastogenesis were significantly higher in OVX mice than in sham mice, while serum TRACP-5b and RANKL levels and osteoclastogenesis were significantly decreased in IL-21 KO + OVX mice compared to WT + OVX mice. IL-21 knockdown reduces TRACP-5b, RANKL, and osteoclastogenesis, effectively preventing bone resorption and alleviating the progression of OVX-induced osteoporosis.

GM-CSF is a marker of compartmentalised intrathecal inflammation in multiple sclerosis

BACKGROUND

Granulocyte-macrophage colony stimulating factor (GM-CSF) is a pro-inflammatory cytokine secreted by various immune cells. Several studies have demonstrated an expansion of GM-CSF producing T cells in the blood or CSF of people with MS (pwMS). However, whether this equates to greater concentrations of circulating cytokine remains unknown as quantification is difficult with traditional assays.

OBJECTIVE

To determine whether GM-CSF can be quantified and whether GM-CSF levels are elevated in pwMS.

METHODS

We employed Single Molecule Array (Simoa) to measure GM-CSF in both CSF and blood. We then investigated relationships between GM-CSF levels and measures of blood-CSF-barrier integrity.

RESULTS

GM-CSF was quantifiable in all samples and was significantly higher in the CSF of pwMS compared with controls. No association was found between CSF GM-CSF levels and Q-Albumin - a measure of blood-CSF-barrier integrity. CSF GM-CSF correlated with measures of intrathecal inflammation, and these relationships were greater in primary progressive MS compared with relapsing-remitting MS.

CONCLUSION

GM-CSF levels are elevated specifically in the CSF of pwMS. Our results suggest that elevated cytokine levels may reflect (at least partial) intrathecal production, as opposed to simple diffusion across a dysfunctional blood-CSF-barrier.

The Glycosaminoglycan Side Chains and Modular Core Proteins of Heparan Sulphate Proteoglycans and the Varied Ways They Provide Tissue Protection by Regulating Physiological Processes and Cellular Behaviour

This review examines the roles of HS-proteoglycans (HS-PGs) in general, and, in particular, perlecan and syndecan as representative examples and their interactive ligands, which regulate physiological processes and cellular behavior in health and disease. HS-PGs are essential for the functional properties of tissues both in development and in the extracellular matrix (ECM) remodeling that occurs in response to trauma or disease. HS-PGs interact with a biodiverse range of chemokines, chemokine receptors, protease inhibitors, and growth factors in immune regulation, inflammation, ECM stabilization, and tissue protection. Some cell regulatory proteoglycan receptors are dually modified hybrid HS/CS proteoglycans (betaglycan, CD47). Neurexins provide synaptic stabilization, plasticity, and specificity of interaction, promoting neurotransduction, neurogenesis, and differentiation. Ternary complexes of glypican-1 and Robbo-Slit neuroregulatory proteins direct axonogenesis and neural network formation. Specific neurexin-neuroligin complexes stabilize synaptic interactions and neural activity. Disruption in these interactions leads to neurological deficits in disorders of functional cognitive decline. Interactions with HS-PGs also promote or inhibit tumor development. Thus, HS-PGs have complex and diverse regulatory roles in the physiological processes that regulate cellular behavior and the functional properties of normal and pathological tissues. Specialized HS-PGs, such as the neurexins, pikachurin, and Eyes-shut, provide synaptic stabilization and specificity of neural transduction and also stabilize the axenome primary cilium of phototoreceptors and ribbon synapse interactions with bipolar neurons of retinal neural networks, which are essential in ocular vision. Pikachurin and Eyes-Shut interactions with an α-dystroglycan stabilize the photoreceptor synapse. Novel regulatory roles for HS-PGs controlling cell behavior and tissue function are expected to continue to be uncovered in this fascinating class of proteoglycan.

GM-CSF distinctly impacts human monocytes and macrophages via ERK1/2-dependent pathways

Human monocytes and macrophages are two major myeloid cell subsets with similar and distinct functions in tissue homeostasis and immune responses. GM-CSF plays a fundamental role in myeloid cell differentiation and activation. Hence, we compared the effects of GM-CSF on the expression of several immune mediators by human monocytes and monocyte-derived macrophages obtained from healthy donors. We report that GM-CSF similarly elevated the expression of CD80 and ICAM-1 and reduced HLA-DR levels on both myeloid cell subsets. However, GM-CSF increased the percentage of macrophages expressing surface IL-15 but reduced the proportion of monocytes carrying surface IL-15. Moreover, GM-CSF significantly increased the secretion of IL-4, IL-6, TNF, CXCL10, and IL-27 by macrophages while reducing the secretion of IL-4 and CXCL10 by monocytes. We show that GM-CSF triggered ERK1/2, STAT3, STAT5, and SAPK/JNK pathways in both myeloid subsets. Using a pharmacological inhibitor (U0126) preventing ERK phosphorylation, we demonstrated that this pathway was involved in both the GM-CSF-induced increase and decrease of the percentage of IL-15+ macrophages and monocytes, respectively. Moreover, ERK1/2 contributed to GM-CSF-triggered secretion of IL-4, IL-6, TNF, IL-27 and CXCL10 by macrophages. However, the ERK1/2 pathway exhibited different roles in monocytes and macrophages for the GM-CSF-mediated impact on surface makers (CD80, HLA-DR, and ICAM-1). Our data demonstrate that GM-CSF stimulation induces differential responses by human monocytes and monocyte-derived macrophages and that some but not all of these effects are ERK-dependent.

CD4 T cells and toxicity from immune checkpoint blockade

Immune-related toxicities, otherwise known as immune-related adverse events (irAEs), occur in a substantial fraction of cancer patients treated with immune checkpoint inhibitors (ICIs). Ranging from asymptomatic to life-threatening, ICI-induced irAEs can result in hospital admission, high-dose corticosteroid treatment, ICI discontinuation, and in some cases, death. A deeper understanding of the factors underpinning severe irAE development will be essential for improved irAE prediction and prevention, toward maximizing the benefits and safety profiles of ICIs. In recent work, we applied mass cytometry, single-cell RNA sequencing, single-cell V(D)J sequencing, bulk RNA sequencing, and bulk T-cell receptor (TCR) sequencing to identify pretreatment determinants of severe irAE development in patients with advanced melanoma. Across 71 patients separated into three cohorts, we found that two baseline features in circulation-elevated activated CD4 effector memory T-cell abundance and TCR diversity-are associated with severe irAE development, independent of the affected organ system within 3 months of ICI treatment initiation. Here, we provide an extended perspective on this work, synthesize and discuss related literature, and summarize practical considerations for clinical translation. Collectively, these findings lay a foundation for data-driven and mechanistic insights into irAE development, with the potential to reduce ICI morbidity and mortality in the future.

TNFα induces matrix metalloproteinase-9 expression in monocytic cells through ACSL1/JNK/ERK/NF-kB signaling pathways

Studies have established the association between increased plasma levels of matrix metalloproteinase (MMP)-9 and adipose tissue inflammation. Tumor necrosis factor α (TNFα) was elevated in obesity and is involved in the induction of MMP-9 in monocytic cells. However, the underlying molecular mechanism was incompletely understood. As per our recent report, TNFα mediates inflammatory responses through long-chain acyl-CoA synthetase 1 (ACSL1). Therefore, we further investigated the role of ACSL1 in TNFα-mediated MMP-9 secretion in monocytic cells. THP-1 cells and primary monocytes were used to study MMP-9 expression. mRNA and protein levels of MMP-9 were determined by qRT-PCR and ELISA, respectively. Signaling pathways were studied using Western blotting, inhibitors, and NF-kB/AP1 reporter cells. We found that THP-1 cells and primary human monocytes displayed increased MMP-9 mRNA expression and protein secretion after incubation with TNFα. ACSL1 inhibition using triacsin C significantly reduced the expression of MMP-9 in the THP-1 cells. However, the inhibition of β-oxidation and ceramide biosynthesis did not affect the TNFα-induced MMP-9 production. Using small interfering RNA-mediated ACSL1 knockdown, we further confirmed that TNFα-induced MMP-9 expression/secretion was significantly reduced in ACSL1-deficient cells. TNFα-mediated MMP-9 expression was also significantly reduced by the inhibition of ERK1/ERK2, JNK, and NF-kB. We further observed that TNFα induced phosphorylation of SAPK/JNK (p54/46), ERK1/2 (p44/42 MAPK), and NF-kB p65. ACSL1 inhibition reduced the TNFα-mediated phosphorylation of SAPK/JNK, c-Jun, ERK1/2, and NF-kB. In addition, increased NF-κB/AP-1 activity was inhibited in triacsin C treated cells. Altogether, our findings suggest that ACSL1/JNK/ERK/NF-kB axis plays an important role in the regulation of MMP-9 induced by TNFα in monocytic THP-1 cells.

Giant Cell Arteritis and Polymyalgia Rheumatica: Treatment Approaches and New Targets

Prolonged glucocorticoid tapers have been the standard of care for giant cell arteritis (GCA) and polymyalgia rheumatica (PMR), but recent advancements have improved outcomes for patients with GCA while reducing glucocorticoid-related toxicities. Many patients with GCA and PMR still experience persistent or relapsing disease, and cumulative exposure to glucocorticoids for both diseases remains high. The objective of this review is to define current treatment approaches as well as new therapeutic targets and strategies. Studies investigating inhibition of cytokine pathways, including interleukin-6, interleukin-17, interleukin-23, granulocyte-macrophage colony-stimulating factor, Janus kinase-signal transduction and activator of transcription, and others, will be reviewed.

Gene Ontology Analysis Highlights Biological Processes Influencing Responsiveness to Biological Therapy in Psoriasis

Psoriasis is a chronic, immune-mediated and inflammatory skin disease. Although various biological drugs are available for psoriasis treatment, some patients have poor responses or do not respond to treatment. The aim of the present study was to highlight the molecular mechanism of responsiveness to current biological drugs for psoriasis treatment. To this end, we reviewed previously published articles that reported genes associated with treatment response to biological drugs in psoriasis, and gene ontology analysis was subsequently performed using the Cytoscape platform. Herein, we revealed a statistically significant association between NF-kappaB signaling (p value = 3.37 × 10-9), regulation of granulocyte macrophage colony-stimulating factor production (p value = 6.20 × 10-6), glial cell proliferation (p value = 2.41 × 10-5) and treatment response in psoriatic patients. To the best of our knowledge, we are the first to directly associate glial cells with treatment response. Taken together, our study revealed gene ontology (GO) terms, some of which were previously shown to be implicated in the molecular pathway of psoriasis, as novel GO terms involved in responsiveness in psoriatic disease patients.

Two Amnion-Derived Mesenchymal Stem-Cells Injections to Osteoarthritic Elbows in Dogs-Pilot Study

The aim of the study was to investigate the potential of cell-based regenerative therapy for elbow joints affected by osteoarthritis. Interest was focused on two intra-articular applications of amnion-derived mesenchymal stem cells (A-MSCs) to a group of different breeds of dogs with elbow osteoarthritis (13 joints). Two injections were performed 14 days apart. We evaluated synovial fluid biomarkers, such as IFN-γ, IL-6, IL-15, IL-10, MCP-1, TNF-α, and GM-CSF, by multiplex fluorescent micro-bead immunoassay in the treated group of elbows (n = 13) (day 0, day 14, and day 28) and in the control group of elbows (n = 9). Kinematic gait analysis determined the joint range of motion (ROM) before and after each A-MSCs application. Kinematic gait analysis was performed on day 0, day 14, and day 28. Kinematic gait analysis pointed out improvement in the average range of motion of elbow joints from day 0 (38.45 ± 5.74°), day 14 (41.7 ± 6.04°), and day 28 (44.78 ± 4.69°) with statistical significance (p < 0.05) in nine elbows. Correlation analyses proved statistical significance (p < 0.05) in associations between ROM (day 0, day 14, and day 28) and IFN-γ, IL-6, IL-15, MCP-1, TNF-α, and GM-CSF concentrations (day 0, day 14, and day 28). IFN-γ, IL-6, IL-15, MCP-1, GM-CSF, and TNF- α showed negative correlation with ROM at day 0, day 14, and day 28, while IL-10 demonstrated positive correlation with ROM. As a consequence of A-MSC application to the elbow joint, we detected a statistically significant (p < 0.05) decrease in concentration levels between day 0 and day 28 for IFN-γ, IL-6, and TNF-α and statistically significant increase for IL-10. Statistical significance (p < 0.05) was detected in TNF-α, IFN-γ, and GM-CSF concentrations between day 14 and the control group as well as at day 28 and the control group. IL-6 concentrations showed statistical significance (p < 0.05) between day 14 and the control group.

Tetramerization of STAT5 regulates monocyte differentiation and the dextran sulfate sodium-induced colitis in mice

In response to external stimuli during immune responses, monocytes can have multifaceted roles such as pathogen clearance and tissue repair. However, aberrant control of monocyte activation can result in chronic inflammation and subsequent tissue damage. Granulocyte-macrophage colony-stimulating factor (GM-CSF) induces monocyte differentiation into a heterogenous population of monocyte-derived dendritic cells (moDCs) and macrophages. However, the downstream molecular signals that dictate the differentiation of monocytes under pathological conditions is incompletely understood. We report here that the GM-CSF-induced STAT5 tetramerization is a critical determinate of monocyte fate and function. Monocytes require STAT5 tetramers to differentiate into moDCs. Conversely, the absence of STAT5 tetramers results in a switch to a functionally distinct monocyte-derived macrophage population. In the dextran sulfate sodium (DSS) model of colitis, STAT5 tetramer-deficient monocytes exacerbate disease severity. Mechanistically, GM-CSF signaling in STAT5 tetramer-deficient monocytes results in the overexpression of arginase I and a reduction in nitric oxide synthesis following stimulation with lipopolysaccharide. Correspondingly, the inhibition of arginase I activity and sustained supplementation of nitric oxide ameliorates the worsened colitis in STAT5 tetramer-deficient mice. This study suggests that STAT5 tetramers protect against severe intestinal inflammation through the regulation of arginine metabolism.

Recent Advances and Research Progress in Biomarkers for Chronic Graft Versus Host Disease

Chronic graft-versus host disease (cGVHD) is a major risk for patients undergoing allogeneic hematopoietic stem cell transplantation. With the emergence of novel therapies and the increased understanding of the mechanisms underlying cGVHD, there are more options for cGVHD treatment. Regardless of improvements in treatment, diagnosis mainly depends on identification of symptoms, which makes precise treatment a challenge. Numerous biomarkers for cGVHD have been validated and have demonstrated strong associations with prognosis and response to treatment. The most common biomarkers mainly include critical types of immune cells, chemokines, cytokines, microRNAs, and autoantibodies, all of which play important roles in the development of cGVHD. Compared to traditional tools, biomarkers have several advantages, for example, they can be applied for early diagnosis, to identify cGVHD risk before onset, and predict which therapy is most likely to benefit patients. In this review, we summarize biomarkers with potential clinical value and discuss future applications.

A randomised trial of anti-GM-CSF otilimab in severe COVID-19 pneumonia (OSCAR)

BACKGROUND

Granulocyte-macrophage colony-stimulating factor (GM-CSF) and dysregulated myeloid cell responses are implicated in the pathophysiology and severity of COVID-19.

METHODS

In this randomised, sequential, multicentre, placebo-controlled, double-blind study, adults aged 18-79 years (Part 1) or ≥70 years (Part 2) with severe COVID-19, respiratory failure and systemic inflammation (elevated C-reactive protein/ferritin) received a single intravenous infusion of otilimab 90 mg (human anti-GM-CSF monoclonal antibody) plus standard care (NCT04376684). The primary outcome was the proportion of patients alive and free of respiratory failure at Day 28.

RESULTS

In Part 1 (n=806 randomised 1:1 otilimab:placebo), 71% of otilimab-treated patients were alive and free of respiratory failure at Day 28 versus 67% who received placebo; the model-adjusted difference of 5.3% was not statistically significant (95% CI -0.8-11.4%, p=0.09). A nominally significant model-adjusted difference of 19.1% (95% CI 5.2-33.1%, p=0.009) was observed in the predefined 70-79 years subgroup, but this was not confirmed in Part 2 (n=350 randomised) where the model-adjusted difference was 0.9% (95% CI -9.3-11.2%, p=0.86). Compared with placebo, otilimab resulted in lower serum concentrations of key inflammatory markers, including the putative pharmacodynamic biomarker CC chemokine ligand 17, indicative of GM-CSF pathway blockade. Adverse events were comparable between groups and consistent with severe COVID-19.

CONCLUSIONS

There was no significant difference in the proportion of patients alive and free of respiratory failure at Day 28. However, despite the lack of clinical benefit, a reduction in inflammatory markers was observed with otilimab, in addition to an acceptable safety profile.

Translating the biology of β common receptor-engaging cytokines into clinical medicine

The family of cytokines that comprises IL-3, IL-5, and GM-CSF was discovered over 30 years ago, and their biological activities and resulting impact in clinical medicine has continued to expand ever since. Originally identified as bone marrow growth factors capable of acting on hemopoietic progenitor cells to induce their proliferation and differentiation into mature blood cells, these cytokines are also recognized as key mediators of inflammation and the pathobiology of diverse immunologic diseases. This increased understanding of the functional repertoire of IL-3, IL-5, and GM-CSF has led to an explosion of interest in modulating their functions for clinical management. Key to the successful clinical translation of this knowledge is the recognition that these cytokines act by engaging distinct dimeric receptors and that they share a common signaling subunit called β-common or βc. The structural determination of how IL-3, IL-5, and GM-CSF interact with their receptors and linking this to their differential biological functions on effector cells has unveiled new paradigms of cell signaling. This knowledge has paved the way for novel mAbs and other molecules as selective or pan inhibitors for use in different clinical settings.

Understanding the development of Th2 cell-driven allergic airway disease in early life

Allergic diseases, including atopic dermatitis, allergic rhinitis, asthma, and food allergy, are caused by abnormal responses to relatively harmless foreign proteins called allergens found in pollen, fungal spores, house dust mites (HDM), animal dander, or certain foods. In particular, the activation of allergen-specific helper T cells towards a type 2 (Th2) phenotype during the first encounters with the allergen, also known as the sensitization phase, is the leading cause of the subsequent development of allergic disease. Infants and children are especially prone to developing Th2 cell responses after initial contact with allergens. But in addition, the rates of allergic sensitization and the development of allergic diseases among children are increasing in the industrialized world and have been associated with living in urban settings. Particularly for respiratory allergies, greater susceptibility to developing allergic Th2 cell responses has been shown in children living in urban environments containing low levels of microbial contaminants, principally bacterial endotoxins [lipopolysaccharide (LPS)], in the causative aeroallergens. This review highlights the current understanding of the factors that balance Th2 cell immunity to environmental allergens, with a particular focus on the determinants that program conventional dendritic cells (cDCs) toward or away from a Th2 stimulatory function. In this context, it discusses transcription factor-guided functional specialization of type-2 cDCs (cDC2s) and how the integration of signals derived from the environment drives this process. In addition, it analyzes observational and mechanistic studies supporting an essential role for innate sensing of microbial-derived products contained in aeroallergens in modulating allergic Th2 cell immune responses. Finally, this review examines whether hyporesponsiveness to microbial stimulation, particularly to LPS, is a risk factor for the induction of Th2 cell responses and allergic sensitization during infancy and early childhood and the potential factors that may affect early-age response to LPS and other environmental microbial components.

An Update on the Emerging Role of Wnt/β-catenin, SYK, PI3K/AKT, and GM-CSF Signaling Pathways in Rheumatoid Arthritis

Rheumatoid arthritis is an untreatable autoimmune disorder. The disease is accompanied by joint impairment and anomalies, which negatively affect the patient's quality of life and contribute to a decline in manpower. To diagnose and treat rheumatoid arthritis, it is crucial to understand the abnormal signaling pathways that contribute to the disease. This understanding will help develop new rheumatoid arthritis-related intervention targets. Over the last few decades, researchers have given more attention to rheumatoid arthritis. The current review seeks to provide a detailed summary of rheumatoid arthritis, highlighting the basic description of the disease, past occurrences, the study of epidemiology, risk elements, and the process of disease progression, as well as the key scientific development of the disease condition and multiple signaling pathways and enumerating the most current advancements in discovering new rheumatoid arthritis signaling pathways and rheumatoid arthritis inhibitors. This review emphasizes the anti-rheumatoid effects of these inhibitors [for the Wnt/β-catenin, Phosphoinositide 3-Kinases (PI3K/AKT), Spleen Tyrosine Kinase (SYK), and Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) signaling pathways], illustrating their mechanism of action through a literature search, current therapies, and novel drugs under pre-clinical and clinical trials.

Immune modulation after traumatic brain injury

Traumatic brain injury (TBI) induces instant activation of innate immunity in brain tissue, followed by a systematization of the inflammatory response. The subsequent response, evolved to limit an overwhelming systemic inflammatory response and to induce healing, involves the autonomic nervous system, hormonal systems, and the regulation of immune cells. This physiological response induces an immunosuppression and tolerance state that promotes to the occurrence of secondary infections. This review describes the immunological consequences of TBI and highlights potential novel therapeutic approaches using immune modulation to restore homeostasis between the nervous system and innate immunity.

Evaluation of porcine GM-CSF during PRRSV infection in vitro and in vivo indicating a protective role of GM-CSF related with M1 biased activation in alveolar macrophage during PRRSV infection

Granulocyte-macrophage colony stimulating factor (GM-CSF), participates in diverse biological processes associated with innate and adaptive immunity, has unknown effects during PRRSV infection. Here, a double-antibody sandwich ELISA for pGM-CSF was developed in-house for evaluation of pGM-CSF level during PRRSV infection both in vitro and in vivo. In in vitro assay, it was notable that PRRSV-infected porcine alveolar macrophages (PAMs) yielded inconsistent pGM-CSF protein- and mRNA-level, suggesting a post-transcriptional inhibition of pGM-CSF mRNA was employed by PRRSV. Meanwhile, concurrent analysis of pGM-CSF levels in serum samples from PRRSV-infected piglets suggested that effect of PRRSV infection demonstrated minimum effect on pGM-CSF levels regardless of PRRSV virulence phenotypes. Moreover, in vitro treatment of PAMs with pGM-CSF prior PRRSV inoculation did not inhibit PRRSV replication in PAMs although genes downstream of pGM-CSF in PAMs could be upregulated by pGM-CSF treatment. Meanwhile, knockdown of pGM-CSF using siRNA did not enhance PRRSV replication as well. Intriguingly, therapeutic antibody treatment of HP-PRRSV-infected piglets led to significantly increased serum pGM-CSF levels, thus aligning with low pneumonia incidence and low intracellular PRRSV-RNA levels in PAMs of therapeutic antibody treated piglets. Furthermore, transcriptome analysis of PAMs from infected piglets revealed increased serum pGM-CSF levels correlated with activation of downstream signal of pGM-CSF in PAMs as evidenced by a M1-like phenotypes of gene expression pattern, implying a potential host-protective role played by pGM-CSF for PRRSV infection in vivo. In conclusion, our results demonstrated developments of a highly sensitive and specific ELISA for pGM-CSF and revealed a potential protective role conferred by pGM-CSF during PRRSV infection.

Neutralizing GM-CSF autoantibodies in pulmonary alveolar proteinosis, cryptococcal meningitis and severe nocardiosis

Background

Anti GM-CSF autoantibodies (aAb) have been related to acquired pulmonary alveolar proteinosis (PAP) and described in cases of severe infections such as cryptococcosis and nocardiosis in previously healthy subjects. Whether there are different anti-GM-CSF autoantibodies corresponding to these phenotypes is unclear. Therefore, we examined anti-GM-CSF autoantibodies to determine whether amount or neutralizing activity could distinguish between groups.

Methods

Plasma samples gathered in the National Institute of Health from patients with anti GM-CSF aAb and either PAP (n = 15), cryptococcal meningitis (n = 15), severe nocardiosis (n = 5) or overlapping phenotypes (n = 6) were compared. The relative amount of aAb was assessed using a particle-based approach, reported as a mouse monoclonal anti-human GM-CSF as standard curve and expressed in an arbitrary Mouse Monoclonal Antibody Unit (MMAU). The neutralizing activity of the plasma was assessed by inhibition of GM-CSF-induced intracellular phospho-STAT5 (pSTAT5) in monocytes.

Results

Anti-GM-CSF aAb relative amounts were higher in PAP patients compared to those with cryptococcosis (mean 495 ± 464 MMAU vs 197 ± 159 MMAU, p = 0.02); there was no difference with patients with nocardiosis (430 ± 493 MMAU) nor between the two types of infections.

The dilution of plasma resulting in 50% inhibition of GM-CSF-induced pSTAT5 (approximate IC₅₀) did not vary appreciably across groups of patients (1.6 ± 3.1%, 3.9 ± 6% and 1.8 ± 2.2% in PAP patients, cryptococcosis and nocardiosis patients, respectively). Nor was the concentration of GM-CSF necessary to induce 50% of maximal GM-CSF-induced pSTAT5 in the presence of 10 MMAU of anti-GM-CSF aAb (EC₅₀). When studying longitudinal samples from patients with PAP or disseminated nocardiosis, the neutralizing effect of anti-GM-CSF aAb was relatively constant over time despite targeted treatments and variations in aAb levels.

Conclusions

Despite different clinical manifestations, anti-GM-CSF antibodies were similar across PAP, cryptococcosis and nocardiosis. Underlying host genetics and functional analyses may help further differentiate the biology of these conditions.

Mechanism of Emodin in the Treatment of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic, systemic, and autoimmune disease, and its main pathological changes are inflammatory cell infiltration accompanied by the secretion and accumulation of a variety of related cytokines, which induce the destruction of cartilage and bone tissue. Therefore, the modulation of inflammatory cells and cytokines is a key therapeutic target for controlling inflammation in RA. This review details the effects of emodin on the differentiation and maturation of T lymphocytes, dendritic cells, and regulatory T cells. In addition, the systematic introduction of emodin directly or indirectly affects proinflammatory cytokines (TNF-α, IL-6, IL-1, IL-1β, IL-17, IL-19, and M-CSF) and anti-inflammatory cytokines (the secretion of IL-4, IL-10, IL-13, and TGF-β) through the coregulation of a variety of inflammatory cytokines to inhibit inflammation in RA and promote recovery. Understanding the potential mechanism of emodin in the treatment of RA in detail provides a systematic theoretical basis for the clinical application of emodin in the future.

Identification of tubulointerstitial genes and ceRNA networks involved in diabetic nephropathy via integrated bioinformatics approaches

Background

Diabetic nephropathy (DN) is the major cause of end-stage renal disease worldwide. The mechanism of tubulointerstitial lesions in DN is not fully elucidated. This article aims to identify novel genes and clarify the molecular mechanisms for the progression of DN through integrated bioinformatics approaches.

Method

We downloaded microarray datasets from Gene Expression Omnibus (GEO) database and identified the differentially expressed genes (DEGs). Enrichment analyses, construction of Protein–protein interaction (PPI) network, and visualization of the co-expressed network between mRNAs and microRNAs (miRNAs) were performed. Additionally, we validated the expression of hub genes and analyzed the Receiver Operating Characteristic (ROC) curve in another GEO dataset. Clinical analysis and ceRNA networks were further analyzed.

Results

Totally 463 DEGs were identified, and enrichment analyses demonstrated that extracellular matrix structural constituents, regulation of immune effector process, positive regulation of cytokine production, phagosome, and complement and coagulation cascades were the major enriched pathways in DN. Three hub genes (CD53, CSF2RB, and LAPTM5) were obtained, and their expression levels were validated by GEO datasets. Pearson analysis showed that these genes were negatively correlated with the glomerular filtration rate (GFR). After literature searching, the ceRNA networks among circRNAs/IncRNAs, miRNAs, and mRNAs were constructed. The predicted RNA pathway of NEAT1/XIST-hsa-miR-155-5p/hsa-miR-486-5p-CSF2RB provides an important perspective and insights into the molecular mechanism of DN.

Conclusion

In conclusion, we identified three genes, namely CD53, CSF2RB, and LAPTM5, as hub genes of tubulointerstitial lesions in DN. They may be closely related to the pathogenesis of DN and the predicted RNA regulatory pathway of NEAT1/XIST-hsa-miR-155-5p/hsa-miR-486-5p-CSF2RB presents a biomarker axis to the occurrence and development of DN.

Mucosal Immune Profiles Associated with Diarrheal Disease Severity in Shigella- and Enteropathogenic Escherichia coli-Infected Children Enrolled in the Global Enteric Multicenter Study

Enteropathogenic Escherichia coli (EPEC) and Shigella are etiologic agents of diarrhea in children <5 years old living in resource-poor countries. Repeated bouts of infection lead to lifelong morbidity and even death. The goal of this study was to characterize local mucosal immune responses in Shigella- and EPEC-infected children <5 years of age with moderate to severe diarrhea (MSD) enrolled in the Global Enteric Multicenter Study (GEMS). We hypothesized that infection with each of these pathogens would induce distinct gut mucosal immune profiles indicative of disease etiology and severity. To test this hypothesis, innate and adaptive immune markers were measured in stools from children with diarrhea due to EPEC, Shigella, or other organisms and in children who had no diarrhea. Shigella-positive diarrhea evoked robust proinflammatory and T_H1/T_H2 cytokine responses compared to diarrhea caused by EPEC or other organisms, with the exception of interleukin 5 (IL-5), which was associated with EPEC infection. The presence of IL-1β, IL-4, IL-16, and tumor necrosis factor beta (TNF-β) was associated with the absence of dysentery. EPEC-positive diarrhea evoked high levels of IL-1β, vascular endothelial growth factor (VEGF), and IL-10. Granulocyte-macrophage colony-stimulating factor (GM-CSF) had opposing roles in disease severity, being associated with absence of diarrhea in EPEC-infected children and with dysenteric Shigella infection. High levels of antigen-specific antibodies were detected in the controls and children with Shigella without dysentery, which suggests a protective role against severe disease. In summary, this study identified distinct local immune responses associated with two clinically relevant diarrheagenic pathogens, Shigella and EPEC, in children and identified protective immune phenotypes that can inform the development of preventive measures.

The innate face of Giant Cell Arteritis: Insight into cellular and molecular innate immunity pathways to unravel new possible biomarkers of disease

Giant cell arteritis (GCA) is an inflammatory chronic disease mainly occurring in elderly individuals. The pathogenesis of GCA is still far from being completely elucidated. However, in susceptible arteries, an aberrant immune system activation drives the occurrence of vascular remodeling which is mainly characterized by intimal hyperplasia and luminal obstruction. Vascular damage leads to ischemic manifestations involving extra-cranial branches of carotid arteries, mostly temporal arteries, and aorta. Classically, GCA was considered a pathological process resulting from the interaction between an unknown environmental trigger, such as an infectious agent, with local dendritic cells (DCs), activated CD4 T cells and effector macrophages. In the last years, the complexity of GCA has been underlined by robust evidence suggesting that several cell subsets belonging to the innate immunity can contribute to disease development and progression. Specifically, a role in driving tissue damage and adaptive immunity activation was described for dendritic cells (DCs), monocytes and macrophages, mast cells, neutrophils and wall components, such as endothelial cells (ECs) and vascular smooth muscle cells (VSMCs). In this regard, molecular pathways related to cytokines, chemokines, growth factors, vasoactive molecules and reactive oxygen species may contribute to the inflammatory process underlying GCA. Altogether, innate cellular and molecular pathways may clarify many pathogenetic aspects of the disease, paving the way for the identification of new biomarkers and for the development of new treatment targets for GCA. This review aims to deeply dissect past and new evidence on the innate immunological disruption behind GCA providing a comprehensive description of disease development from the innate perspective.

STAT3 regulates inflammatory cytokine production downstream of TNFR1 by inducing expression of TNFAIP3/A20

Tumour Necrosis Factor (TNF) potently induces a transient inflammatory response that must be downregulated once any invasive stimulus has resolved. Yet, how TNF‐induced inflammation is shut down in normal cells is incompletely understood. The present study shows that STAT3 was activated in mouse embryo fibroblasts (MEFs) by treatment with TNF or an agonist antibody to TNFR1. STAT3 activation was inhibited by pharmacological inhibition of the Jak2 tyrosine kinase that associates with TNFR1. To identify STAT3 target genes, global transcriptome analysis by RNA sequencing was performed in wild‐type MEFs and MEFs from STAT3 knockout (STAT3^KO) mice that were stimulated with TNF, and the results were validated at the protein level by using multiplex cytokine assays and immunoblotting. After TNF stimulation, STAT3^KO MEFs showed greater gene and protein induction of the inflammatory chemokines Ccl2, Cxcl1 and Cxcl10 than WT MEFs. These observations show that, by activating STAT3, TNF selectively modulates expression of a cohort of chemokines that promote inflammation. The greater induction by TNF of chemokines in STAT3^KO than WT MEFs suggested that TNF induced an inhibitory protein in WT MEFs. Consistent with this possibility, STAT3 activation by TNFR1 increased the expression of Tnfaip3/A20, a ubiquitin modifying enzyme that inhibits inflammation, in WT MEFs but not in STAT3^KO MEFs. Moreover, enforced expression of Tnfaip3/A20 in STAT3^KO MEFs suppressed proinflammatory chemokine expression induced by TNF. Our observations identify Tnfaip3/A20 as a new downstream target for STAT3 which limits the induction of Ccl2, Cxcl1 and Cxcl10 and inflammation induced by TNF.

Research progress on the pathogenesis of aortic dissection

Aortic dissection (AD) is a critical cardiovascular disease due to the separation of media and adventitia caused by the rupture of vascular wall intima. The disease has a high mortality rate of about 1% to 3% for each additional hour, since the adventitia of the aorta can rupture and bleed to death at any time. Although great progress has been made in clinical treatment of aortic dissection, and the mortality rate has been significantly reduced, the pathogenesis is still not very clear. At present, related studies have confirmed that inflammation of aortic wall promotes the occurrence and development of AD. Although the mechanism of aortic dissection is more complicated, some studies have shown that the infiltration of monocytes/macrophages into the aortic wall is the main pathogenic mechanism of the disease. This review introduces the latest research results on the mechanism of macrophage infiltration and plasticity in aortic dissection.

Single-cell immune profiling reveals a developmentally distinct CD4+ GM-CSF+ T-cell lineage that induces GI tract GVHD

Gastrointestinal (GI) tract involvement is a major determinant for subsequent morbidity and mortality arising during graft-versus-host disease (GVHD). CD4+ T cells that produce granulocyte-macrophage colony stimulating factor (GM-CSF) have emerged as central mediators of inflammation in this tissue site as GM-CSF serves as a critical cytokine link between the adaptive and innate arms of the immune system. However, cellular heterogeneity within the CD4+ GM-CSF+ T-cell population due to the concurrent production of other inflammatory cytokines has raised questions as to whether these cells have a common ontology or if a unique CD4+ GM-CSF+ subset exists that differs from other defined T helper subtypes. Using single-cell RNA sequencing analysis (scRNAseq), we identified two CD4+ GM-CSF+ T-cell populations that arose during GVHD and were distinguishable according to the presence or absence of interferon-γ (IFN-γ) coexpression. CD4+ GM-CSF+ IFN-γ- T cells, which emerged preferentially in the colon, had a distinct transcriptional profile, used unique gene regulatory networks, and possessed a nonoverlapping T-cell receptor repertoire compared with CD4+ GM-CSF+ IFN-γ+ T cells as well as all other transcriptionally defined CD4+ T-cell populations in the colon. Functionally, this CD4+ GM-CSF+ T-cell population contributed to pathologic damage in the GI tract that was critically dependent on signaling through the interleukin-17 (IL-7) receptor but was independent of type 1 interferon signaling. Thus, these studies help to unravel heterogeneity within CD4+ GM-CSF+ T cells that arise during GVHD and define a developmentally distinct colitogenic T helper subtype GM-CSF+ subset that mediates immunopathology.

DOCK2 regulates antifungal immunity by regulating RAC GTPase activity

Fungal infections cause ~1.5 million deaths each year worldwide, and the mortality rate of disseminated candidiasis currently exceeds that of breast cancer and malaria. The major reasons for the high mortality of candidiasis are the limited number of antifungal drugs and the emergence of drug-resistant species. Therefore, a better understanding of antifungal host defense mechanisms is crucial for the development of effective preventive and therapeutic strategies. Here, we report that DOCK2 (dedicator of cytokinesis 2) promotes indispensable antifungal innate immune signaling and proinflammatory gene expression in macrophages. DOCK2-deficient macrophages exhibit decreased RAC GTPase (Rac family small GTPase) activation and ROS (reactive oxygen species) production, which in turn attenuates the killing of intracellular fungi and the activation of downstream signaling pathways. Mechanistically, after fungal stimulation, activated SYK (spleen-associated tyrosine kinase) phosphorylates DOCK2 at tyrosine 985 and 1405, which promotes the recruitment and activation of RAC GTPases and then increases ROS production and downstream signaling activation. Importantly, nanoparticle-mediated delivery of in vitro transcribed (IVT) Rac1 mRNA promotes the activity of Rac1 and helps to eliminate fungal infection in vivo. Taken together, this study not only identifies a critical role of DOCK2 in antifungal immunity via regulation of RAC GTPase activity but also provides proof of concept for the treatment of invasive fungal infections by using IVT mRNA.

Function and therapeutic value of astrocytes in neurological diseases

Astrocytes are abundant glial cells in the central nervous system (CNS) that perform diverse functions in health and disease. Astrocyte dysfunction is found in numerous diseases, including multiple sclerosis, Alzheimer disease, Parkinson disease, Huntington disease and neuropsychiatric disorders. Astrocytes regulate glutamate and ion homeostasis, cholesterol and sphingolipid metabolism and respond to environmental factors, all of which have been implicated in neurological diseases. Astrocytes also exhibit significant heterogeneity, driven by developmental programmes and stimulus-specific cellular responses controlled by CNS location, cell-cell interactions and other mechanisms. In this Review, we highlight general mechanisms of astrocyte regulation and their potential as therapeutic targets, including drugs that alter astrocyte metabolism, and therapies that target transporters and receptors on astrocytes. Emerging ideas, such as engineered probiotics and glia-to-neuron conversion therapies, are also discussed. We further propose a concise nomenclature for astrocyte subsets that we use to highlight the roles of astrocytes and specific subsets in neurological diseases.

The pre-induction temperature affects recombinant HuGM-CSF aggregation in thermoinducible Escherichia coli

The overproduction of recombinant proteins in Escherichia coli leads to insoluble aggregates of proteins called inclusion bodies (IBs). IBs are considered dynamic entities that harbor high percentages of the recombinant protein, which can be found in different conformational states. The production conditions influence the properties of IBs and recombinant protein recovery and solubilization. The E. coli growth in thermoinduced systems is generally carried out at 30 °C and then recombinant protein production at 42 °C. Since the heat shock response in E. coli is triggered above 34 °C, the synthesis of heat shock proteins can modify the yields of the recombinant protein and the structural quality of IBs. The objective of this work was to evaluate the effect of different pre-induction temperatures (30 and 34 °C) on the growth of E. coli W3110 producing the human granulocyte-macrophage colony-stimulating factor (rHuGM-CSF) and on the IBs structure in a λpL/pR-cI857 thermoinducible system. The recombinant E. coli cultures growing at 34 °C showed a ~ 69% increase in the specific growth rate compared to cultures grown at 30 °C. The amount of rHuGM-CSF in IBs was significantly higher in cultures grown at 34 °C. Main folding chaperones (DnaK and GroEL) were associated with IBs and their co-chaperones (DnaJ and GroES) with the soluble protein fraction. Finally, IBs from cultures that grew at 34 °C had a lower content of amyloid-like structure and were more sensitive to proteolytic degradation than IBs obtained from cultures at 30 °C. Our study presents evidence that increasing the pre-induction temperature in a thermoinduced system allows obtaining higher recombinant protein and reducing amyloid contents of the IBs. KEY POINTS: • Pre-induction temperature determines inclusion bodies architecture • In pre-induction (above 34 °C), the heat shock response increases recombinant protein production • Inclusion bodies at higher pre-induction temperature show a lower amyloid content.