A dendritic-cell-derived C-C chemokine that preferentially attracts naive T cells

Chemokine ligand 18 predicts all-cause mortality in patients hospitalized with chest pain of suspected coronary origin

Introduction

Chemokines mediate recruitment and activation of leucocytes. Chemokine ligand 18 (CCL18) is mainly expressed by monocytes/macrophages and dendritic cells. It is highly expressed in chronic inflammatory diseases, and locally in atherosclerotic plaques, particularly at sites of reduced stability, and systemically in acute coronary syndrome patients. Reports on its prognostic utility in the latter condition, including myocardial infarction (MI), are scarce.

Aim

To assess the utility of CCL18 as a prognostic marker of recurrent cardiovascular events in patients hospitalized with chest pain of suspected coronary origin.

Methods

The population consisted of 871 consecutive chest-pain patients, of whom 386 were diagnosed with acute myocardial infarction (AMI) based on Troponin-T (TnT) levels >50 ng/L. Stepwise Cox regression models, applying normalized continuous loge/SD values, were fitted for the biomarkers with cardiac mortality within 2 years and total mortality within 2 and 7 years as the dependent variables.

Results

Plasma samples from 849 patients were available. By 2 years follow-up, 138 (15.8%) patients had died, of which 86 were cardiac deaths. Univariate analysis showed a positive, significant association between CCL18 and total death [HR 1.55 (95% 1.30-1.83), p < 0.001], and for cardiac death [HR 1.32 (95% 1.06-1.64), p = 0.013]. Associations after adjustment were non-significant. By 7 years follow-up, 332 (38.1%) patients had died. CLL18 was independently associated with all-cause mortality [HR 1.14 (95% CI, 1.01-1.29), p = 0.030], but not with MI (n = 203) or stroke (n = 55).

Conclusion

CCL18 independently predicts long-term all-cause mortality but had no independent prognostic bearing on short-term cardiac death and CVD events.

Immunotherapy Innovations in the Fight against Osteosarcoma: Emerging Strategies and Promising Progress

Immunosuppressive elements within the tumor microenvironment are the primary drivers of tumorigenesis and malignant advancement. The presence, as well as the crosstalk between myeloid-derived suppressor cells (MDSCs), osteosarcoma-associated macrophages (OS-Ms), regulatory T cells (Tregs), and endothelial cells (ECs) with osteosarcoma cells cause the poor prognosis of OS. In addition, the consequent immunosuppressive factors favor the loss of treatment potential. Nanoparticles offer a means to dynamically and locally manipulate immuno-nanoparticles, which present a promising strategy for transforming OS-TME. Additionally, chimeric antigen receptor (CAR) technology is effective in combating OS. This review summarizes the essential mechanisms of immunosuppressive cells in the OS-TME and the current immune-associated strategies. The last part highlights the limitations of existing therapies and offers insights into future research directions.

Pro-Fibrotic Effects of CCL18 on Human Lung Fibroblasts Are Mediated via CCR6

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease of unknown origin, with a median patient survival time of ~3 years after diagnosis without anti-fibrotic therapy. It is characterized by progressive fibrosis indicated by increased collagen deposition and high numbers of fibroblasts in the lung. It has been demonstrated that CCL18 induces collagen and αSMA synthesis in fibroblasts. We aimed to identify the CCL18 receptor responsible for its pro-fibrotic activities.

METHODS

We used a random phage display library to screen for potential CCL18-binding peptides, demonstrated its expression in human lungs and fibroblast lines by PCR and immunostaining and verified its function in cell lines.

RESULTS

We identified CCR6 (CD196) as a CCL18 receptor and found its expression in fibrotic lung tissue and lung fibroblast lines derived from fibrotic lungs, but it was almost absent in control lines and tissue. CCL18 induced receptor internalization in a CCR6-overexpressing cell line. CCR6 blockade in primary human lung fibroblasts reduced CCL18-induced FGF2 release as well as collagen-1 and αSMA expression. Knockdown of CCR6 in a mouse fibroblast cell line abolished the induction of collagen and α-smooth muscle actin expression.

CONCLUSION

Our data indicate that CCL18 triggers pro-fibrotic processes via CCR6, highlighting its role in fibrogenesis.

TREM2 inhibition triggers antitumor cell activity of myeloid cells in glioblastoma

Triggering receptor expressed on myeloid cells 2 (TREM2) plays important roles in brain microglial function in neurodegenerative diseases, but the role of TREM2 in the GBM TME has not been examined. Here, we found that TREM2 is highly expressed in myeloid subsets, including macrophages and microglia in human and mouse GBM tumors and that high TREM2 expression correlates with poor prognosis in patients with GBM. TREM2 loss of function in human macrophages and mouse myeloid cells increased interferon-γ-induced immunoactivation, proinflammatory polarization, and tumoricidal capacity. In orthotopic mouse GBM models, mice with chronic and acute Trem2 loss of function exhibited decreased tumor growth and increased survival. Trem2 inhibition reprogrammed myeloid phenotypes and increased programmed cell death protein 1 (PD-1)+CD8+ T cells in the TME. Last, Trem2 deficiency enhanced the effectiveness of anti-PD-1 treatment, which may represent a therapeutic strategy for patients with GBM.

Nitrogen-Centered Lactate Oxidase Nanozyme for Tumor Lactate Modulation and Microenvironment Remodeling

Designing nanozymes that match natural enzymes have always been an attractive and challenging goal. In general, researchers mainly focus on the construction of metal centers and the control of non-metallic ligands of nanozyme to regulate their activities. However, this is not applicable to lactate oxidase, i.e., flavoenzymes with flavin mononucleotide (FMN)-dependent pathways. Herein, we propose a coordination strategy to mimic lactate oxidase based on engineering the electronic properties at the N center by modulating the Co number near N in the Co_x-N nanocomposite. Benefitting from the manipulated coordination fields and electronic structure around the electron-rich N sites, Co₄N/C possesses a precise recognition site for lactate and intermediate organization and optimizes the absorption energies for intermediates, leading to superior oxidation of the lactate α-C-sp(3)-H bond toward ketone. The optimized nanozyme delivers much improved anticancer efficacy by reversing the high lactate and the immunosuppressive state of the tumor microenvironment, subsequently achieving excellent tumor growth and distant metastasis inhibition. The developed Co₄N/C NEs open a new window for building a bridge between chemical catalysis and biocatalysis.

Adipose tissue specific CCL18 associates with cardiometabolic diseases in non-obese individuals implicating CD4+ T cells

AIM

Obesity is linked to cardiometabolic diseases, however non-obese individuals are also at risk for type 2 diabetes (T2D) and cardiovascular disease (CVD). White adipose tissue (WAT) is known to play a role in both T2D and CVD, but the contribution of WAT inflammatory status especially in non-obese patients with cardiometabolic diseases is less understood. Therefore, we aimed to find associations between WAT inflammatory status and cardiometabolic diseases in non-obese individuals.

METHODS

In a population-based cohort containing non-obese healthy (n = 17), T2D (n = 16), CVD (n = 18), T2D + CVD (n = 19) individuals, seventeen different cytokines were measured in WAT and in circulation. In addition, 13-color flow cytometry profiling was employed to phenotype the immune cells. Human T cell line (Jurkat T cells) was stimulated by rCCL18, and conditioned media (CM) was added to the in vitro cultures of human adipocytes. Lipolysis was measured by glycerol release. Blocking antibodies against IFN-γ and TGF-β were used in vitro to prove a role for these cytokines in CCL18-T-cell-adipocyte lipolysis regulation axis.

RESULTS

In CVD, T2D and CVD + T2D groups, CCL18 and CD4+ T cells were upregulated significantly compared to healthy controls. WAT CCL18 secretion correlated with the amounts of WAT CD4+ T cells, which also highly expressed CCL18 receptors suggesting that WAT CD4+ T cells are responders to this chemokine. While direct addition of rCCL18 to mature adipocytes did not alter the adipocyte lipolysis, CM from CCL18-treated T cells increased glycerol release in in vitro cultures of adipocytes. IFN-γ and TGF-β secretion was significantly induced in CM obtained from T cells treated with CCL18. Blocking these cytokines in CM, prevented CM-induced upregulation of adipocyte lipolysis.

CONCLUSION

We suggest that in T2D and CVD, increased production of CCL18 recruits and activates CD4+ T cells to secrete IFN-γ and TGF-β. This, in turn, promotes adipocyte lipolysis - a possible risk factor for cardiometabolic diseases.

Integrative analysis of bulk and single-cell gene expression profiles to identify tumor-associated macrophage-derived CCL18 as a therapeutic target of esophageal squamous cell carcinoma

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is a common gastrointestinal malignancy with poor patient prognosis. Current treatment for ESCC, including immunotherapy, is only beneficial for a small subset of patients. Better characterization of the tumor microenvironment (TME) and the development of novel therapeutic targets are urgently needed.

METHODS

In the present study, we hypothesized that integration of single-cell transcriptomic sequencing and large microarray sequencing of ESCC biopsies would reveal the key cell subtypes and therapeutic targets that determine the prognostic and tumorigenesis of ESCC. We characterized the gene expression profiles, gene sets enrichment, and the TME landscape of a microarray cohort including 84 ESCC tumors and their paired peritumor samples. We integrated single-cell transcriptomic sequencing and bulk microarray sequencing of ESCC to reveal key cell subtypes and druggable targets that determine the prognostic and tumorigenesis of ESCC. We then designed and screened a blocking peptide targeting Chemokine C-C motif ligand 18 (CCL18) derived from tumor associated macrophages and validated its potency by MTT assay. The antitumor activity of CCL18 blocking peptide was validated in vivo by using 4-nitroquinoline-1-oxide (4-NQO) induced spontaneous ESCC mouse model.

RESULTS

Comparative gene expression and cell-cell interaction analyses revealed dysregulated chemokine and cytokine pathways during ESCC carcinogenesis. TME deconvolution and cell interaction analyses allow us to identify the chemokine CCL18 secreted by tumor associated macrophages could promote tumor cell proliferation via JAK2/STAT3 signaling pathway and lead to poor prognosis of ESCC. The peptide Pep3 could inhibit the proliferation of EC-109 cells promoted by CCL18 and significantly restrain the tumor progression in 4-NQO-induced spontaneous ESCC mouse model.

CONCLUSIONS

For the first time, we discovered and validated that CCL18 blockade could significantly prevent ESCC progression. Our study revealed the comprehensive cell-cell interaction network in the TME of ESCC and provided novel therapeutic targets and strategies to ESCC treatment.

Signature transcriptome analysis of stage specific atherosclerotic plaques of patients

Background

Inflammation plays an important role in all the stages of atherosclerotic plaque development. The current study aimed at assessing the altered expression of genes functioning in inflammation within the early stage (ES) and advanced stage (AS) atherosclerotic plaques obtained from patients undergoing coronary artery bypass grafting (CABG) surgery and identifying biomarker panel/s that may detect the status of plaque stages using peripheral blood samples.

Methods

A section of ES and AS plaques and normal left internal mammary arteries (LIMA) were obtained from 8 patients undergoing the CABG surgery. Total RNA isolated was analyzed for mRNA and miRNA expression profile by Affymetrix arrays. A significant number of mRNAs was found to be differentially expressed in ES and AS plaque tissues relative to LIMA. The pathway analysis of differentially expressed mRNAs in the two plaque stages was also performed using DAVID Bioinformatics Database.

Results

The mRNAs were found to be involved in critical inflammatory processes such as the toll-like receptor signaling pathway and cytokine-cytokine receptor interaction. Few miRNAs targeting these mRNAs were also altered in the two plaque conditions. QRT-PCR results showed a similar expression pattern of a few of the mRNAs and miRNAs in peripheral blood of the same patients relative to healthy controls.

Conclusion

Changes in mRNA and miRNA expression associated with various inflammatory processes occur in different atherosclerotic stage plaques as well as peripheral blood. Detection of such variations in patients’ blood can be used as a possible prognostic tool to detect and/or predict the risk and stage of atherosclerosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12920-022-01250-8.

Delayed Effect of Dendritic Cells Vaccination on Survival in Glioblastoma: A Systematic Review and Meta-Analysis

Background: Dendritic cell vaccination (DCV) strategies, thanks to a complex immune response, may flare tumor regression and improve patients’ long-term survival. This meta-analysis aims to assess the efficacy of DCV for newly diagnosed glioblastoma patients in clinical trials. Methods: The study databases, including PubMed, Web of Knowledge, Google Scholar, Scopus, and Cochrane, were searched by two blinded investigators considering eligible studies based on the following keywords: “glioblastoma multiforme”, “dendritic cell”, “vaccination”, “immunotherapy”, “immune system”, “immune response”, “chemotherapy”, “recurrence”, and “temozolomide”. Among the 157 screened, only 15 articles were eligible for the final analysis. Results: Regimens including DCV showed no effect on 6-month progression-free survival (PFS, HR = 1.385, 95% CI: 0.822–2.335, p = 0.673) or on 6-month overall survival (OS, HR = 1.408, 95% CI: 0.882–2.248, p = 0.754). In contrast, DCV led to significantly longer 1-year OS (HR = 1.936, 95% CI: 1.396–2.85, p = 0.001) and longer 2-year OS (HR = 3.670, 95% CI: 2.291–5.879, p = 0.001) versus control groups. Hence, introducing DCV could lead to increased 1 and 2-year survival of patients by 1.9 and 3.6 times, respectively. Conclusion: Antitumor regimens including DCV can effectively improve mid-term survival in patients suffering glioblastoma multiforme (GBM), but its impact emerges only after one year from vaccination. These data indicate the need for more time to achieve an anti-GBM immune response and suggest additional therapeutics, such as checkpoint inhibitors, to empower an earlier DCV action in patients affected by a very poor prognosis.

Chemokine CCL18 Promotes Phagocytosis Through Its Receptor CCR8 Rather than PITPNM3 in Human Microglial Cells

CCL18 is a CC chemokine that exhibits diverse functions through interaction with various cell subsets with both proinflammatory anti-inflammatory properties through its receptors CCR8 (CC chemokine receptor 8) and PITPNM3 (phosphatidylinositol transfer protein 3). However, the function of CCL18 in microglia remains unclear. In this study, we show that CCL18 did not change the expression of the inflammatory factors, interleukin (IL)-1β, IL-6, tumor necrosis factor alpha (TNF-α), or inducible nitric oxide synthase (iNOS), but significantly induced expression of the macrophage markers, MRC-1 and ARG-1 M2, in a human microglial clone 3 cell line (HMC3). Phagocytosis by HMC3 cells was significantly enhanced in the presence of CCL18, indicated by uptake of amyloid-β and dextran. CCR8 and PITPNM3 were both expressed on HMC3 cells, but selective knockdown of CCR8 and PITPNM3 showed that only the former played a dominant role in phagocytosis of HMC3 through the nuclear factor kappa B (NF-κB)/Src signaling pathway. Our results suggest that CCL18 could have anti-inflammatory activity and activate the phagocytic function of microglia, which is involved in neural development, homeostasis, and repair mechanisms.

The Critical Importance of Spatial and Temporal Scales in Designing and Interpreting Immune Cell Migration Assays

Intravital microscopy and other direct-imaging techniques have allowed for a characterisation of leukocyte migration that has revolutionised the field of immunology, resulting in an unprecedented understanding of the mechanisms of immune response and adaptive immunity. However, there is an assumption within the field that modern imaging techniques permit imaging parameters where the resulting cell track accurately captures a cell's motion. This notion is almost entirely untested, and the relationship between what could be observed at a given scale and the underlying cell behaviour is undefined. Insufficient spatial and temporal resolutions within migration assays can result in misrepresentation of important physiologic processes or cause subtle changes in critical cell behaviour to be missed. In this review, we contextualise how scale can affect the perceived migratory behaviour of cells, summarise the limited approaches to mitigate this effect, and establish the need for a widely implemented framework to account for scale and correct observations of cell motion. We then extend the concept of scale to new approaches that seek to bridge the current "black box" between single-cell behaviour and systemic response.

Epithelial-mesenchymal Transition of Peritoneal Mesothelial Cells Is Enhanced by M2c Macrophage Polarization

BACKGROUND

Peritoneal fibrosis (PF) can reduce the efficiency of peritoneal dialysis and eventually lead to ultrafiltration failure. Epithelial-mesenchymal transition (EMT) of peritoneal mesothelial cells (PMCs) is the start of PF. Macrophages are involved in the process. This study was to investigate the effect of macrophage polarization on EMT of PMCs.

METHODS

Monocyte-macrophage cells (THP-1) were treated to induce macrophage subsets (M1, M2a, M2c). The inducing was assessed by detecting protein and mRNA expression of cytokines using ELISA and RT-PCR. Subsequently, PMCs were co-cultured with M1, M2a and M2c, respectively, in Transwell chambers for 48 h and then expressions of E-cadherin and α-SMA were determined in PMCs. The PMCs that were not co-cultured with macrophages served as control PMCs. One-way ANOVA and SNK-q test were used to conduct statistics and P < .05 as significant.

RESULTS

Detection of the cytokines, including IL-6, IL-10, IL-12, TGF-β1, CCL17 and CXCL13, verified that the inducting of macrophage subtypes was successful. Compared to control, E-cadherin protein expression was significantly decreased and α-SMA protein expression increased in M1-treated PMCs (P < .05); M2a-treated PMCs had an increased gene expression of α-SMA (P < .05); E-cadherin protein and gene expression were decreased and α-SMA protein and gene expression increased significantly in M2c-treated PMCs (P < .05 or P < .01).

CONCLUSIONS

EMT of PMCs is enhanced by M2c macrophage polarization; meanwhile, M1 and M2a polarization may have the effect to some extent, but not as definite as M2c.

A multi-cellular molecular signaling and functional network map of C-C motif chemokine ligand 18 (CCL18): a chemokine with immunosuppressive and pro-tumor functions

The C-C Motif Chemokine Ligand 18 (CCL18) is a beta-chemokine sub-family member with immunomodulatory functions in primates. CCL18-dependent migration and epithelial-to-mesenchymal transition of oral squamous cell carcinoma, squamous cell carcinoma of head and neck, breast cancer, hepatocellular carcinoma, non-small cell lung carcinoma, ovarian cancer, pancreatic ductal carcinoma and bladder cancer cells are well-established. In the tumor niche, tumor-associated macrophages produce CCL18 and its overexpression is correlated with reduced patient survival in multiple cancers. Although multiple receptors including C-C chemokine receptor type 3 (CCR3), type 6 (CCR6), type 8 (CCR8) and G-protein coupled estrogen receptor (GPER1) are reported for CCL18, the Phosphatidylinositol Transfer Protein, Membrane-Associated 3 (PITPNM3) receptor is currently considered as its predominant receptor. Characterization of the molecular events and check points associated with the immunosuppressive and cancer progression support functions induced by CCL18 for their potential towards therapeutic applications is an area of active research. Hence, in this study, we assembled 917 signaling events reported to be induced by CCL18 through their studied receptors in diverse cell types as an integrated knowledgebase for reference, data integration and gene-set enrichment analysis of global transcriptomic and/or proteomics datasets.

The C-X-C Motif Chemokine Ligand 1 Sustains Breast Cancer Stem Cell Self-Renewal and Promotes Tumor Progression and Immune Escape Programs

Breast cancer (BC) mortality is mainly due to metastatic disease, which is primarily driven by cancer stem cells (CSC). The chemokine C-X-C motif ligand-1 (CXCL1) is involved in BC metastasis, but the question of whether it regulates breast cancer stem cell (BCSC) behavior is yet to be explored. Here, we demonstrate that BCSCs express CXCR2 and produce CXCL1, which stimulates their proliferation and self-renewal, and that CXCL1 blockade inhibits both BCSC proliferation and mammosphere formation efficiency. CXCL1 amplifies its own production and remarkably induces both tumor-promoting and immunosuppressive factors, including SPP1/OPN, ACKR3/CXCR7, TLR4, TNFSF10/TRAIL and CCL18 and, to a lesser extent, immunostimulatory cytokines, including IL15, while it downregulates CCL2, CCL28, and CXCR4. CXCL1 downregulates TWIST2 and SNAI2, while it boosts TWIST1 expression in association with the loss of E-Cadherin, ultimately promoting BCSC epithelial-mesenchymal transition. Bioinformatic analyses of transcriptional data obtained from BC samples of 1,084 patients, reveals that CXCL1 expressing BCs mostly belong to the Triple-Negative (TN) subtype, and that BC expression of CXCL1 strongly correlates with that of pro-angiogenic and cancer promoting genes, such as CXCL2-3-5-6, FGFBP1, BCL11A, PI3, B3GNT5, BBOX1, and PTX3, suggesting that the CXCL1 signaling cascade is part of a broader tumor-promoting signaling network. Our findings reveal that CXCL1 functions as an autocrine growth factor for BCSCs and elicits primarily tumor progression and immune escape programs. Targeting the CXCL1/CXCR2 axis could restrain the BCSC compartment and improve the treatment of aggressive BC.

PARC/CCL18 is Associated with Inflammation, Emphysema Severity and Application of Inhaled Corticosteroids in Hospitalized COPD Patients

Background

Pulmonary and activation-regulated chemokine (PARC) also named CC-chemokine ligand 18 (CCL18) is a lung-predominant inflammatory protein that is found in serum. The relationship of PARC/CCL18 with the chronic obstructive pulmonary disease (COPD) is not fully understood. The aim of the present study is to analyze the expression of PARC/CCL18 in COPD.

Methods

Ninety-eight hospitalized COPD patients and 60 healthy volunteers from January 2019 to December 2019 were recruited in this retrospective study. Gender, age, height, weight, disease duration, smoking status, blood cell classification and count, length of hospital stay (LOS), symptom score, including COPD Assessment Test (CAT) score, modified British Medical Research Council (mMRC) score, lung function and therapy were recorded and serum PARC/CCL18 was analyzed by ELISA. The correlation between symptom score, blood cell classification and count, CRP, lung function parameters and serum levels of PARC/CCL18 and ROC curves of PARC/CCL18 levels and inhaled corticosteroids (ICS) were accessed.

Results

It was found that serum PARC/CCL18 level in hospitalized COPD population was significantly higher than that in healthy people (p=0.003). COPD patients with emphysema had significantly higher serum level of PARC/CCL18 than those without emphysema (p=0.049). Total lung capacity (TLC) and residual volume (RV)/TLC had positive correlation with serum level of PARC/CCL18 (p=0.001, 0.020, respectively). Furthermore, serum PARC/CCL18 level was predictive for the application ICS (p=0.003) and related to C-reactive protein (p <0.0001) in hospitalized COPD patients.

Conclusion

PARC/CCL18 is associated with the severity of inflammation and emphysema in COPD. Furthermore, PARC/CCL18 is a predictor of ICS application in the treatment of hospitalized COPD patients.

Natural Killer Cells from Allergic Donors Are Defective in Their Response to CCL18 Chemokine

Natural killer (NK) cells were originally described as cytolytic effector cells, but since then have been recognized to possess regulatory functions on immune responses. Chemokines locate NK cells throughout the body in homeostatic and pathological conditions. They may also directly stimulate immune cells. CCL18 is a constitutive and inducible chemokine involved in allergic diseases. The aim of this study was to evaluate CCL18’s effect on NK cells from allergic and nonallergic donors in terms of both chemotactic and immune effects. Results showed that CCL18 was able to induce migration of NK cells from nonallergic donors in a G-protein-dependent manner, suggesting the involvement of a classical chemokine receptor from the family of seven-transmembrane domain G-protein-coupled receptors. In contrast, NK cells from allergic patients were unresponsive. Similarly, CCL18 was able to induce NK cell cytotoxicity only in nonallergic subjects. Purified NK cells did not express CCR8, one of the receptors described to be involved in CCL18 functions. Finally, the defect in CCL18 response by NK cells from allergic patients was unrelated to a defect in CCL18 binding to NK cells. Overall, our results suggest that some NK cell functions may be defective in allergic diseases.

The immunosuppressive and pro-tumor functions of CCL18 at the tumor microenvironment

Chemokines are essential mediators of immune cell trafficking. In a tumor microenvironment context, chemotactic cytokines are known to regulate the migration, positioning and interaction of different cell subsets with both anti- and pro-tumor functions. Additionally, chemokines have critical roles regarding non-immune cells, highlighting their importance in tumor growth and progression. CCL18 is a primate-specific chemokine produced by macrophages and dendritic cells. This chemokine presents both constitutive and inducible expression. It is mainly associated with a tolerogenic response and involved in maintaining homeostasis of the immune system under physiological conditions. Recently, CCL18 has been noticed as an important component of the complex chemokine system involved in the biology of tumors. This chemokine induces T regulatory cell differentiation and recruitment to the tumor milieu, with subsequent induction of a pro-tumor (M2-like) macrophage phenotype. CCL18 is also directly involved in cancer cell-invasion, migration, epithelial-to-mesenchymal transition and angiogenesis stimulation, pinpointing an important role in the promotion of cancer progression. Interestingly, this chemokine is highly expressed in tumor tissues, particularly at the invasive front of more advanced stages (e.g. colorectal cancer), and high levels are detected in the serum of patients, correlating with poor prognosis. Despite the promising role of CCL18 as a biomarker and/or therapeutic target to hamper disease progression, its pleiotropic functions in a context of cancer are still poorly explored. The scarce knowledge concerning the receptors for this chemokine, together with the insufficient insight on the downstream signaling pathways, have impaired the selection of this molecule as an immediate target for translational research. In this Review, we will discuss recent findings concerning the role of CCL18 in cancer, integrate recently disclosed molecular mechanisms and compile data from current clinical studies.

The stress-axis in multiple sclerosis: Clinical, cellular, and molecular aspects

Altered activity of the hypothalamus-pituitary-adrenal (HPA) stress-axis has been implicated in the pathogenesis and progression of multiple sclerosis (MS) and linked to the development of specific symptoms and comorbidities such as mood disorders, fatigue, or cognitive dysfunction. Overall the HPA-axis is activated or hyperresponsive in MS, though a hyporesponsive HPA-axis has been observed in a subgroup of MS patients that has a more severe course of the disease. Here we provide an overview of the possible causes of HPA-axis activation, sex- and subtype dependent differences, pathological, cellular, and molecular effects, and the clinical correlates of HPA-axis activity in MS.

Plasma matrix metalloproteinase 7, CC-chemokine ligand 18, and periostin as markers for pulmonary sarcoidosis

BACKGROUND

Some patients with sarcoidosis experience worsening of pulmonary lesions. However, no biomarker has been identified that reflects pulmonary disease status in sarcoidosis. We investigated the usefulness of potential markers of pulmonary fibrosis in patients with sarcoidosis.

METHODS

Plasma matrix metalloproteinase 7 (MMP-7), CC-chemokine ligand 18 (CCL-18), and periostin levels were evaluated in 60 patients with sarcoidosis and 30 healthy controls; bronchoalveolar lavage fluid levels were analyzed in 22 patients with sarcoidosis. To determine the usefulness of these markers, we explored potential correlations between these markers and sarcoidosis clinical characteristics.

RESULTS

Plasma MMP-7, CCL-18, and periostin concentrations were significantly higher in patients with sarcoidosis than those in healthy controls. MMP-7 concentrations in plasma and bronchoalveolar lavage fluid were higher in patients with sarcoidosis with parenchymal infiltration than in those without lung lesions. Moreover, MMP-7 concentration was negatively correlated with pulmonary function.

CONCLUSION

Among these novel biomarkers, MMP-7 most precisely reflected pulmonary sarcoidosis disease status and thus, might be useful for diagnosing and evaluating sarcoidosis, particularly in patients with pulmonary parenchymal lesions.

CCL18 in the Progression of Cancer

A neoplastic tumor consists of cancer cells that interact with each other and non-cancerous cells that support the development of the cancer. One such cell are tumor-associated macrophages (TAMs). These cells secrete many chemokines into the tumor microenvironment, including especially a large amount of CCL18. This chemokine is a marker of the M2 macrophage subset; this is the reason why an increase in the production of CCL18 is associated with the immunosuppressive nature of the tumor microenvironment and an important element of cancer immune evasion. Consequently, elevated levels of CCL18 in the serum and the tumor are connected with a worse prognosis for the patient. This paper shows the importance of CCL18 in neoplastic processes. It includes a description of the signal transduction from PITPNM3 in CCL18-dependent migration, invasion, and epithelial-to-mesenchymal transition (EMT) cancer cells. The importance of CCL18 in angiogenesis has also been described. The paper also describes the effect of CCL18 on the recruitment to the cancer niche and the functioning of cells such as TAMs, regulatory T cells (T_reg), cancer-associated fibroblasts (CAFs) and tumor-associated dendritic cells (TADCs). The last part of the paper describes the possibility of using CCL18 as a therapeutic target during anti-cancer therapy.

CC Chemokines in a Tumor: A Review of Pro-Cancer and Anti-Cancer Properties of Receptors CCR5, CCR6, CCR7, CCR8, CCR9, and CCR10 Ligands

CC chemokines (or β-chemokines) are 28 chemotactic cytokines with an N-terminal CC domain that play an important role in immune system cells, such as CD4⁺ and CD8⁺ lymphocytes, dendritic cells, eosinophils, macrophages, monocytes, and NK cells, as well in neoplasia. In this review, we discuss human CC motif chemokine ligands: CCL1, CCL3, CCL4, CCL5, CCL18, CCL19, CCL20, CCL21, CCL25, CCL27, and CCL28 (CC motif chemokine receptor CCR5, CCR6, CCR7, CCR8, CCR9, and CCR10 ligands). We present their functioning in human physiology and in neoplasia, including their role in the proliferation, apoptosis resistance, drug resistance, migration, and invasion of cancer cells. We discuss the significance of chemokine receptors in organ-specific metastasis, as well as the influence of each chemokine on the recruitment of various cells to the tumor niche, such as cancer-associated fibroblasts (CAF), Kupffer cells, myeloid-derived suppressor cells (MDSC), osteoclasts, tumor-associated macrophages (TAM), tumor-infiltrating lymphocytes (TIL), and regulatory T cells (T_reg). Finally, we show how the effect of the chemokines on vascular endothelial cells and lymphatic endothelial cells leads to angiogenesis and lymphangiogenesis.

Genetic Variation in CCL18 Gene Influences CCL18 Expression and Correlates with Survival in Idiopathic Pulmonary Fibrosis: Part A

Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic disease, characterized by fibroblast proliferation and extracellular matrix deposition. CC-chemokine ligand 18 (CCL18) upregulates the production of collagen by lung fibroblasts and is associated with mortality. This study was designed to evaluate the influence of single nucleotide polymorphisms (SNPs) in the CCL18 gene on CCL18 expression and survival in IPF. Serum CCL18 levels and four SNPs in the CCL18 gene were analyzed in 77 Dutch IPF patients and 349 healthy controls (HCs). CCL18 mRNA expression was analyzed in peripheral blood mononuclear cells (PBMCs) from 18 healthy subjects. Survival analysis was conducted, dependent on CCL18-levels and -genotypes and validated in two German IPF cohorts (Part B). IPF patients demonstrated significantly higher serum CCL18 levels than the healthy controls (p < 0.001). Both in IPF patients and HCs, serum CCL18 levels were influenced by rs2015086 C > T genotype, with the highest CCL18-levels with the presence of the C-allele. Constitutive CCL18 mRNA-expression in PBMCs was significantly increased with the C-allele and correlated with serum CCL18-levels. In IPF, high serum levels correlated with decreased survival (p = 0.02). Survival was worse with the CT-genotype compared to the TT genotype (p = 0.01). Concluding, genetic variability in the CCL18-gene accounts for differences in CCL18 mRNA-expression and serum-levels and influences survival in IPF.

Serum CCL 18 Levels in Women with Polycystic Ovarian Syndrome

BACKGROUND

Polycystic ovarian syndrome (PCOS) is one of the most common metabolic disorders seen in women of the reproductive age group, with the majority of them having insulin resistance. There is a need to identify sensitive markers of insulin resistance. CC chemokine ligand 18 (CCL 18) secreted from white adipose tissue is upregulated in individuals with insulin resistance.

OBJECTIVES

To study the correlation between serum CCL 18 levels and insulin resistance in PCOS.

MATERIALS AND METHODS

This case-control study included 45 PCOS women and an equal number of age and body mass index (BMI) matched controls. Estimation of serum CCL 18, serum testosterone, fasting plasma glucose, fasting insulin, HbA1c, and ultrasonography of abdomen and pelvis was done and HOMA IR was calculated.

RESULTS

Serum CCL 18 level was higher in women with PCOS when compared to controls. The mean level of serum CCL 18 (ng/mL) in the PCOS group and control group was 28.32 ± 4.17 and 11.90 ± 4.91, respectively (P < 0.001). Blood pressure, waist circumference, waist-hip ratio, modified Ferriman Gallway score (FG) score serum total testosterone, fasting serum insulin, and HOMA IR showed a relationship with serum CCL 18 levels. Serum CCL 18 was an independent predictor of PCOS (P < 0.05). A serum CCL 18 cutoff level of 18.84 ng/mL showed 93.3% sensitivity and 91.7% specificity in distinguishing PCOS subjects from healthy individuals.

CONCLUSION

There is a significant correlation of serum CCL 18 level with insulin resistance in PCOS subjects and serum CCL levels can be considered as a marker of PCOS.

Magnoliae Flos Essential Oil as an Immunosuppressant in Dendritic Cell Activation and Contact Hypersensitivity Responses

Magnoliae Flos is a commonly used traditional medicinal material in Asia. It is used to treat sinusitis, nasal congestion, and hypersensitive skin. Because Magonlia Flos was described as an aromatic material in ancient Chinese texts, we hypothesized that its essential oil may be used to treat immune disorders. Dendritic cells (DCs), regarded as a major target of immunomodulators to control immune responses, play a critical role in the adaptive immune response. In this study, Magnoliae Flos essential oil (MFEO) decreased the production of the cytokines TNF-[Formula: see text], IL-6, and IL-12p70 in lipopolysaccharide (LPS)-stimulated DCs. It also suppressed the surface markers MHC II, CD80, and CD86 in LPS-stimulated DCs. Animal models demonstrated that the 2,4-Dinitro-1-fluorobenzene (DNFB) inducing a contact hypersensitivity response was inhibited following treatment with MFEO. In addition, MFEO inhibited the infiltration of T cells in the ears of DNFB-induced mice. To explore its bioactive compounds, the components of MFEO were analyzed using gas chromatography (GC) and GC-mass spectrometry. The results revealed that the major compounds in MFEO are camphor and 1,8-cineole. Additional DC bioassays confirmed that these compounds substantially suppressed cytokine production in LPS-induced DCs. Therefore, we demonstrated that MFEO exhibits an immunosuppressive effect both in vivo and in vitro, and camphor and 1,8-cineole may be the major components responsible for its immunosuppressive ability. The findings indicate that MFEO has the potential to be developed as a new immunosuppressant for excessive diseases.

Blocking drug-induced autophagy with chloroquine in HCT-116 colon cancer cells enhances DC maturation and T cell responses induced by tumor cell lysate

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Autophagy helps tumor cells to face drug-induced damages, stimulating tolerance.

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Autophagy inhibition improves the efficiency of antineoplastic agents.

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Blockage of autophagy with Chloroquine increases synthesis of tumor antigens.

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Blockage of autophagy changes the expression of ATG and tumor suppressor genes.

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Lysate of drug-treated cells enhances maturation/activation of human dendritic cells.

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Lysate of drug-treated cells induce Th1 alloresponse, and generation of tumor-specific CTL.

Autophagy is an important mechanism for tumor escape, allowing tumor cells to recover from the damage induced by chemotherapy, radiation therapy, and immunotherapy and contributing to the development of resistance. The pharmacological inhibition of autophagy contributes to increase the efficacy of antineoplastic agents. Exposing tumor cells to low concentrations of select autophagy-inducing antineoplastic agents increases their immunogenicity and enhances their ability to stimulate dendritic cell (DC) maturation. We tested whether the application of an autophagy-inhibiting agent, chloroquine (CQ), in combination with low concentrations of 5-fluorouracil (5-FU) increases the ability of tumor cells to induce DC maturation. DCs sensitized with the lysate of HCT-116 cells previously exposed to such a combination enhanced the DC maturation/activation ability. These matured DCs also increased the allogeneic responsiveness of both CD4+ and CD8+ T cells, which showed a greater proliferative response than those from DCs sensitized with control lysates. The T cells expanded in such cocultures were CD69+ and PD-1- and produced higher levels of IFN-γ and lower levels of IL-10, consistent with the preferential activation of Th1 cells. Cocultures of autologous DCs and lymphocytes improved the generation of cytotoxic T lymphocytes, as assessed by the expression of CD107a, perforin, and granzyme B. The drug combination increased the expression of genes related to the CEACAM family (BECN1, ATGs, MAPLC3B, ULK1, SQSTM1) and tumor suppressors (PCBP1). Furthermore, the decreased expression of genes related to metastasis and tumor progression (BNIP3, BNIP3L, FOSL2, HES1, LAMB3, LOXL2, NDRG1, P4HA1, PIK3R2) was noted. The combination of 5-FU and CQ increases the ability of tumor cells to drive DC maturation and enhances the ability of DCs to stimulate T cell responses.

The Role of Chemokines in the Pathogenesis of HTLV-1

Human T cell leukemia virus type 1 (HTLV-1) is a human retrovirus that is associated with two main diseases: HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and adult T cell leukemia/lymphoma (ATL). Chemokines are highly specialized groups of cytokines that play important roles in organizing, trafficking, homing, and in the migration of immune cells to the bone marrow, lymphoid organs and sites of infection and inflammation. Aberrant expression or function of chemokines, or their receptors, has been linked to the protection against or susceptibility to specific infectious diseases, as well as increased the risk of autoimmune diseases and malignancy. Chemokines and their receptors participate in pathogenesis of HTLV-1 associated diseases from inflammation in the central nervous system (CNS) which occurs in cases of HAM/TSP to T cell immortalization and tissue infiltration observed in ATL patients. Chemokines represent viable effective prognostic biomarkers for HTLV-1-associated diseases which provide the early identification of high-risk, treatment possibilities and high-yielding clinical trials. This review focuses on the emerging roles of these molecules in the outcome of HTLV-1-associated diseases.

Characterisation of tumour microenvironment and immune checkpoints in primary central nervous system diffuse large B cell lymphomas

Primary central nervous system diffuse large B cell lymphoma (PCNS-DLBCL) is a rare and aggressive entity of diffuse large B cell lymphoma (DLBCL). Elements of the tumour microenvironment (TME) including tumour-infiltrating lymphocytes (TILs) and tumour-associated macrophages (TAMs) have been associated with survival in DLBCL but their composition and prognostic impact in PCNS-DLBCL are unknown. Programmed cell death-1 (PD1)/programmed death-ligand 1 (PD-L1) immune checkpoint may represent a therapeutic option. Here, we aimed to characterise PD1/PDL1 immune checkpoints and the composition of the TME in PCNS-DLBCL. We collected tumour tissue and clinical data from 57 PCNS-DLBCL and used immunohistochemistry to examine TAMs (CD68, CD163), TILs (CD3, CD4, CD8, PD1) and tumour B cells (PAX5/PDL1 double stains, PDL1). The PDL1 gene was evaluated by fluorescence in situ hybridization (FISH). PAX5/PDL1 identified PDL1 expression by tumour B cells in 10/57 cases (17.5%). PDL1 gene translocation was a recurrent cytogenetic alteration in PNCS-DLBCL (8/47.17%) and was correlated with PDL1 positive expression in tumour B cells. The TME consisted predominantly of CD163 (+) M2 TAMs and CD8 (+) TILs. Most TAMs expressed PDL1 and most TILs expressed PD1. The density of TAMs and TILs did not associate with outcome. We showed that expression of PD1 on TILs and PDL1 on TAMs, but not the expression of PDL1 on tumour B cells was correlated with better prognosis. These findings support a significant role of TME composition and PD1/PDL1 crosstalk in PCNS-DLBCL pathogenesis and bring new insights to the targeted therapy of this aggressive lymphoma.

A Gene Expression-based Model to Predict Metabolic Response After Two Courses of ABVD in Hodgkin Lymphoma Patients

PURPOSE

Early response to ABVD, assessed with interim FDG-PET (iPET), is prognostic for classical Hodgkin lymphoma (cHL) and supports the use of response adapted therapy. The aim of this study was to identify a gene-expression profile on diagnostic biopsy to predict iPET positivity (iPET⁺).

EXPERIMENTAL DESIGN

Consecutive untreated patients with stage I-IV cHL who underwent iPET after two cycles of ABVD were identified. Expression of 770 immune-related genes was analyzed by digital expression profiling (NanoString Technology). iPET was centrally reviewed according to the five-point Deauville scale (DS 1-5). An iPET⁺ predictive model was derived by multivariate regression analysis and assessed in a validation set identified using the same inclusion criteria.

RESULTS

A training set of 121 and a validation set of 117 patients were identified, with 23 iPET⁺ cases in each group. Sixty-three (52.1%), 19 (15.7%), and 39 (32.2%) patients had stage I-II, III, and IV, respectively. Diagnostic biopsy of iPET⁺ cHLs showed transcriptional profile distinct from iPET^-. Thirteen genes were stringently associated with iPET⁺. This signature comprises two functionally stromal-related nodes. Lymphocytes/monocytes ratio (LMR) was also associated to iPET⁺. In the training cohort a 5-gene/LMR integrated score predicted iPET⁺ [AUC, 0.88; 95% confidence interval (CI), 0.80-0.96]. The score achieved a 100% sensitivity to identify DS5 cases. Model performance was confirmed in the validation set (AUC, 0.68; 95% CI, 0.52-0.84). Finally, iPET score was higher in patients with event versus those without.

CONCLUSIONS

In cHL, iPET is associated with a genetic signature and can be predicted by applying an integrated gene-based model on the diagnostic biopsy.

Increased Plasma Levels of the TH2 chemokine CCL18 associated with low CD4+ T cell counts in HIV-1-infected Patients with a Suppressed Viral Load

The chemokine (C-C motif) chemokine ligand 18 (CCL18) is a structural homolog of CCL3 primarily produced by monocyte-derived cells with an M2 phenotype. Elevated levels of CCL18 have been observed in several diseases associated with malignancies and chronic inflammation. The role of CCL18 in Human Immunodeficiency Virus (HIV-1) infection remains unknown. We analyzed expression levels of T helper cell-mediated (TH2) chemokines CCL18, CCL17, and CCL22 by ELISA in plasma collected from HIV-1-infected and healthy donors. In HIV-1-infected individuals, plasma viral loads were monitored by NucliSense HIV-1 QT assay and T cell counts and expression of the activation marker CD38 were determined by flow cytometry. Our data showed a significant increase in plasma levels of CCL18 in HIV-1-infected individuals compared to uninfected controls (p < 0.001) and a significant correlation between CCL18 levels and viral load in untreated patients. No significant difference of CCL18 levels was detected among the HIV-1-infected patients treated with combined antiretroviral therapy (cART) and HIV-1-untreated patients.CCL18 values are negatively correlated with CD4+CD38+ cell numbers and total CD4+ T cell counts in patients with a suppressed viral load. Notably, plasma levels of the TH2 chemokines CCL17 and CCL22 are also elevated during HIV-1 infection. However, no correlation of CCL17 and CCL22 production with CD4+ T cell counts was detected. Presented data shows that the chemokines, CCL17, CCL18, and CCL22 are increased during HIV-1 infection. However, only increased levels of CCL18, a marker of M2 macrophages, correlate with low CD4+ T cell counts in patients with suppressed viral load, raising the possibility that CCL18 and/or CCL18-producing cells may interfere with their reconstitution in HIV-1-infected patients on cART.

New Insights in Bladder Cancer Diagnosis: Urinary miRNAs and Proteins

Bladder cancer is the 10th-most common cancer worldwide. The diagnosis and follow-up of patients require costly invasive methods and due to these expenses, bladder cancer continues to be one of the expensive malignancies. Early diagnosis is crucial in bladder cancer as it is in other cancers; therefore, non-invasive biomarkers for early diagnosis are very important. In this review, we aimed to focus on the most recent investigations on potential urinary micro RNA (miRNA) and protein biomarkers for bladder cancer diagnosis and their associated pathways. Studies performed by different groups were compiled and the biomarker properties of various proteins and miRNAs in the urine of bladder cancer patients were evaluated. Key studies were obtained by searching keywords “bladder cancer, urinary miRNA, urinary protein, urinary biomarker”. Targets and the pathways of the miRNAs and proteins were analyzed according to mirBase Catalogue and Panther Database. The major pathways that are targeted by aberrantly expressed miRNAs are Cholecystokinin receptor (CCKR), p53, Wnt signaling pathway, and feedback loops. We hereby conclude that urinary micro RNAs and proteins are promising candidates for bladder cancer diagnosis. It should be noted that urine collection, storage conditions, choice of fraction, and normalization strategies should be standardized.

Chemokine-Induced Macrophage Polarization in Inflammatory Conditions

Macrophages represent a heterogeneous cell population and are known to display a remarkable plasticity. In response to distinct micro-environmental stimuli, e.g., tumor stroma vs. infected tissue, they polarize into different cell subtypes. Originally, two subpopulations were defined: classically activated macrophages or M1, and alternatively activated macrophages or M2. Nowadays, the M1/M2 classification is considered as an oversimplified approach that does not adequately cover the total spectrum of macrophage phenotypes observed in vivo. Especially in pathological circumstances, macrophages behave as plastic cells modifying their expression and transcription profile along a continuous spectrum with M1 and M2 phenotypes as extremes. Here, we focus on the effect of chemokines on macrophage differentiation and polarization in physiological and pathological conditions. In particular, we discuss chemokine-induced macrophage polarization in inflammatory diseases, including obesity, cancer, and atherosclerosis.

The expression of CCL18 in diffuse large B cell lymphoma and its mechanism research

BACKGROUND

Molecular target therapy has become a hot spot in cancer treatment, finding effective targets for diffuse large B cell lymphoma (DLBCL) is an urgent problem.

OBJECTIVE

To detect the expression level of C-C motif chemokine ligand 18 (CCL18) in DLBCL and clarify its potential role in the progression of DLBCL.

METHODS

Gene expression datas of DLBCL were obtained from TCGA and GEO databases. The relationship between CCL18 and clinicopathologic information of DLBCL was assessed using meta-analysis method. Then we conducted bioinformatics analysis to uncover the biological function of CCL18 and its co-expression genes. Immunohistochemistry was applied to detect expression of CCL18 in DLBCL and reactive hyperplasia lymphoid tissues.

RESULTS

The expression of CCL18 in DLBCL was higher than negative control group. The levels of CCL18 were distinct in different molecular subtypes and ages, and patients with higher level of CCL18 had a shorter overall survival than those with lower level. CCL18 and its co-expression genes were enriched in biological function such as cell proliferation, migration, apoptotic, and correlated with NF-κB, pathway in cancer, PI3K-AKT pathway.

CONCLUSIONS

CCL18 was up-regulated in DLBCL and related to poor prognosis. CCL18 may act as a valuable target for diagnosis and treatment of DLBCL.

Randomized controlled phase III trial of adjuvant chemoimmunotherapy with activated cytotoxic T cells and dendritic cells from regional lymph nodes of patients with lung cancer

Randomized controlled trial of adjuvant chemoimmunotherapy for lung cancer indicated a significant advantage in patients receiving immunotherapy. Herein we report the final results and immunological analysis with a median follow-up of 59.6 months. Patients with post-surgical lung cancer were randomly designated to receive either chemoimmunotherapy (group A, immunotherapy arm) or chemotherapy (group B, control arm). The immunotherapy comprised the adoptive transfer of autologous activated killer T cells and dendritic cells (AKT-DC). The 2- and 5-year overall survival (OS) rates were 96.0 and 69.4% in group A and 64.7 and 45.1% in group B, respectively. Multivariate analysis results revealed that the hazard ratio was 0.439. The 2- and 5-year recurrence-free survival rates were 70.0 and 57.9% in group A and 43.1 and 31.4% in group B, respectively. Subgroup analysis for the OS between treatment groups indicated that younger patients (≤ 55 years: HR 0.098), males (HR 0.474), patients with adenocarcinoma (HR 0.479), patients with stage III cancer (HR 0.399), and those who did not receive preoperative chemotherapy (HR 0.483) had lower HRs than those in the other groups. Immunological analysis of cell surface markers in regional lymph nodes of subjects receiving immunotherapy indicated that the CD8⁺/CD4⁺ T-cell ratio was elevated in survivors. Patients with non-small-cell lung cancer benefited from adoptive cellular immunotherapy as an adjuvant to surgery. Patients with stage III cancer, those with adenocarcinoma, and those not receiving preoperative chemotherapy were good candidates. Lastly, cytotoxic T cells were important for a favorable chemoimmunotherapy outcome.

Adipose tissue extrinsic factor: Obesity-induced inflammation and the role of the visceral lymph node

Obesity-related adverse health consequences occur predominately in individuals with upper body fat distribution commonly associated with increased central adiposity. Visceral adipose tissue accumulation is described to be the greatest driver of obesity-induced inflammation, however evidence also supports that the intestines fundamentally contribute to the development of obesity-induced metabolic disease. The visceral adipose depot shares the same vasculature and lymph drainage as the small intestine. We hypothesize that the visceral lymph node, which drains adipose tissue and the gastrointestinal tract, is central to the exacerbation of systemic pro-inflammation. Male C57BL/6 mice were fed CHOW or high fat diet (HFD) for 7 weeks. At termination the mesenteric depot, visceral lymph node and ileum, jejunum and Peyer's patches were collected. Cytokine concentration was determined in adipose tissue whereas immune cell populations where investigated in the visceral lymph node and intestinal segments by flow cytometry. Visceral adipose tissue and the gastrointestinal tract mutually influence immune cells enclosed within the visceral lymph node. HFD increased visceral lymph node immune cell number. This likely resulted from 1.) an increase in immune cells migration from the small intestines likely from activated dendritic cells that travel to the lymph node and 2.) cytokine effluent from visceral adipose tissue that promoted expansion, survival and retention of pro-inflammatory immune cells. Overall, the visceral lymph node, the immune nexus of visceral adipose tissue and the small intestines, likely plays a fundamental role in exacerbation of systemic pro-inflammation by HFD-induced obesity. The research of Tim Bartness greatly enhanced the understanding of adipose tissue regulation. Studies from his laboratory significantly contributed to our awareness of extrinsic factors that influence body fatness levels. Specifically, the work he produced eloquently demonstrated that adipose tissue was more complex than an insulating storage center; it was connected to our brains via the sympathetic and sensory nervous system. Mapping studies demonstrated that adipose tissue both receives and sends information to the brain. Further, his lab demonstrated that nervous system connections contributed to lipolysis, thermogenesis and adipocyte proliferation and growth. The work of Tim Bartness will continue to influence adipose tissue research. As such, Tim Bartness directly inspired the following research. Adipose tissue extrinsic factors are not limited to the peripheral nervous system. The lymphatic system is an additional extrinsic factor that cross talks with adipose tissue, however its role in this context is under emphasized. Here we begin to elucidate how the lymphatic system may contribute to the comorbidities associated with visceral adipose tissue accumulation.

CCL18 - Beyond chemotaxis

The chemokine CCL18 is constitutively expressed in human lung and serum, and is further elevated during pathologic conditions such as allergy, fibrosis and cancer, suggesting that it may participate in both homeostatic and inflammatory processes. Under steady state conditions, CCL18 has chemotactic activity, albeit modest, toward naïve T cells and as such, may be involved in the initiation of the adaptive response. Its chemotactic effect on inflammatory cells is ambiguous as it attracts both regulatory and inflammatory immune cells. CCL18 can also modulate tissue inflammation by inhibiting cell recruitment through binding to glycosaminoglycans with high affinity, thereby displacing other chemokines bound to the endothelial surface. CCL18 induces regulatory phenotype and function of immune cells through direct activation and plays a major role in fibrotic processes, particularly in the lung. Finally, CCL18 is involved in cancer cell activation and migration and also participates in immune tolerance toward cancer. Its high constitutive expression levels and its further up-regulation in many diseases, together with its moderate chemoattractant properties support the fact that this chemokine has activities beyond cell recruitment.

Course of SP-D, YKL-40, CCL18 and CA 15-3 in adult patients hospitalised with community-acquired pneumonia and their association with disease severity and aetiology: A post-hoc analysis

BACKGROUND AND AIM

SP-D, YKL-40, CCL18 and CA 15-3 are pulmonary markers that have been extensively investigated in different chronic pulmonary diseases. However, in acute pulmonary diseases, such as community-acquired pneumonia (CAP), little is known about the course of these markers and their relationship with the aetiological agent. The aim of this study was to investigate the course of these four markers in CAP and to study influence of disease severity, aetiology and antibiotic use prior to admission on their course.

METHODS

We included 291 adult patients hospitalised with CAP and 20 healthy controls. Measurements were performed in serum of day 0, 2, and 4, and at least 30 days after admission.

RESULTS

Our most important results were: 1) At all time-points, including 30 days after admission, YKL-40 and CCL18 levels were higher in CAP patients compared to healthy controls; and 2) Patients with CAP caused by an intracellular, atypical bacterium had lower YKL-40 and especially CCL18 levels on and during admission in comparison with other or unknown CAP aetiology.

CONCLUSIONS

Our findings suggest that these pulmonary markers could be useful to assess CAP severity and, especially YKL-40 and CCL18 by helping predict CAP caused by atypical pathogens.

Regulation of Human Macrophage M1-M2 Polarization Balance by Hypoxia and the Triggering Receptor Expressed on Myeloid Cells-1

Macrophages (Mf) are a heterogeneous population of tissue-resident professional phagocytes and a major component of the leukocyte infiltrate at sites of inflammation, infection, and tumor growth. They can undergo diverse forms of activation in response to environmental factors, polarizing into specialized functional subsets. A common hallmark of the pathologic environment is represented by hypoxia. The impact of hypoxia on human Mf polarization has not been fully established. The objective of this study was to elucidate the effects of a hypoxic environment reflecting that occurring in vivo in diseased tissues on the ability of human Mf to polarize into classically activated (proinflammatory M1) and alternatively activated (anti-inflammatory M2) subsets. We present data showing that hypoxia hinders Mf polarization toward the M1 phenotype by decreasing the expression of T cell costimulatory molecules and chemokine homing receptors and the production of proinflammatory, Th1-priming cytokines typical of classical activation, while promoting their acquisition of phenotypic and secretory features of alternative activation. Furthermore, we identify the triggering receptor expressed on myeloid cells (TREM)-1, a member of the Ig-like immunoregulatory receptor family, as a hypoxia-inducible gene in Mf and demonstrate that its engagement by an agonist Ab reverses the M2-polarizing effect of hypoxia imparting a M1-skewed phenotype to Mf. Finally, we provide evidence that Mf infiltrating the inflamed hypoxic joints of children affected by oligoarticular juvenile idiopatic arthritis express high surface levels of TREM-1 associated with predominant M1 polarization and suggest the potential of this molecule in driving M1 proinflammatory reprogramming in the hypoxic synovial environment.

Blocking the recruitment of naive CD4+ T cells reverses immunosuppression in breast cancer

The origin of tumor-infiltrating Tregs, critical mediators of tumor immunosuppression, is unclear. Here, we show that tumor-infiltrating naive CD4⁺ T cells and Tregs in human breast cancer have overlapping TCR repertoires, while hardly overlap with circulating Tregs, suggesting that intratumoral Tregs mainly develop from naive T cells in situ rather than from recruited Tregs. Furthermore, the abundance of naive CD4⁺ T cells and Tregs is closely correlated, both indicating poor prognosis for breast cancer patients. Naive CD4⁺ T cells adhere to tumor slices in proportion to the abundance of CCL18-producing macrophages. Moreover, adoptively transferred human naive CD4⁺ T cells infiltrate human breast cancer orthotopic xenografts in a CCL18-dependent manner. In human breast cancer xenografts in humanized mice, blocking the recruitment of naive CD4⁺ T cells into tumor by knocking down the expression of PITPNM3, a CCL18 receptor, significantly reduces intratumoral Tregs and inhibits tumor progression. These findings suggest that breast tumor-infiltrating Tregs arise from chemotaxis of circulating naive CD4⁺ T cells that differentiate into Tregs in situ. Inhibiting naive CD4⁺ T cell recruitment into tumors by interfering with PITPNM3 recognition of CCL18 may be an attractive strategy for anticancer immunotherapy.

STAT3 and NF-κB are Simultaneously Suppressed in Dendritic Cells in Lung Cancer

Tumour-induced dendritic cell (DC) dysfunction plays an important role in cancer immune escape. However, the underlying mechanisms are not yet fully understood, reflecting the lack of appropriate experimental models both in vivo and in vitro. In the present study, an in vitro study model for tumour-induced DC dysfunction was established by culturing DCs with pooled sera from multiple non-small cell lung cancer (NSCLC) patients. The results demonstrated that tumour-induced human monocyte-derived DCs exhibited systematic functional deficiencies. Transcriptomics analysis revealed that the expression of major functional cluster genes, including the MHC class II family, cytokines, chemokines, and co-stimulatory molecules, was significantly altered in tumour-induced DCs compared to that in control cells. Further examination confirmed that both NF-κB and STAT3 signalling pathways were simultaneously repressed by cancer sera, suggesting that the attenuated NF-κB and STAT3 signalling could be the leading cause of DC dysfunction in cancer. Furthermore, reversing the deactivated NF-κB and STAT3 signalling could be a strategy for cancer immunotherapy.

YKL-40, CCL18 and SP-D predict mortality in patients hospitalized with community-acquired pneumonia

BACKGROUND AND OBJECTIVE

The aim of this study was to investigate the prognostic value of four biomarkers, YKL-40, chemokine (C-C motif) ligand 18 (CCL18), surfactant protein-D (SP-D) and CA 15-3, in patients admitted with community-acquired pneumonia (CAP). These markers have been studied extensively in chronic pulmonary disease, but in acute pulmonary disease their prognostic value is unknown.

METHODS

A total of 289 adult patients who were hospitalized with CAP and participated in a randomized controlled trial were enrolled. Biomarker levels were measured on the day of admission. Intensive care unit admission, 30-day, 1-year and long-term mortality (median follow-up of 5.4 years, interquartile range (IQR): 4.7-6.1) were recorded as outcomes.

RESULTS

Median YKL-40 and CCL18 levels were significantly higher and levels of SP-D were significantly lower in CAP patients compared to healthy controls. Significantly higher YKL-40, CCL18 and SP-D levels were found in patients classified in pneumonia severity index classes 4-5 and with a CURB-65 score ≥2 compared to patients with less severe pneumonia. Furthermore, these three markers were significant predictors for long-term mortality in multivariate analysis and compared with C-reactive protein and procalcitonin level on admission, area under the curves were higher for 30-day, 1-year and long-term mortality. CA 15-3 levels were less predictive.

CONCLUSION

YKL-40, CCL18 and SP-D levels were higher in patients with more severe pneumonia, possibly reflecting the extent of pulmonary inflammation. Of these, YKL-40 most significantly predicts mortality for CAP.

Elevation of Activated Platelet-Dependent Chemokines in Patients With Anti-CD20 Monoclonal Antibody (Rituximab)−Treated Non-Hodgkin's Lymphoma

.ocn.ne.jp. This study measured and compared levels of some chemokines in patients with rituximab-treated non-Hodgkin lymphoma because they may participate in the mechanism of efficacy of rituximab in non-Hodgkin lymphoma patients. Monocytic chemotactant protein-1, RANTES (regulated on activation, normally T-cell expressed and secreted), eotaxin, interleukin-8, neutrophil-activating protein-78, stromal cell-derived factor-1, and growth-regulating oncogene-α in patients with rituximab-treated non-Hodgkin lymphoma were measured by enzyme-linked immunosorbent assay. Levels of RANTES were higher in non-Hodgkin lymphoma patients than in controls. Levels of monocytic chemotactant protein-1, RANTES, and neutrophil-activating protein-78 were significantly elevated before and after chemotherapy with rituximab treatment. However, the level of stromal cell-derived factor-1 did not exhibit a significant change. Before to after chemotherapy without rituximab treatment, all chemokine levels did not exhibit significant changes. These findings suggest that activated platelet-dependent chemokines such as RANTES and neutrophil-activating protein-78 may modulate the efficacy of rituximab in antibody-dependent cellular cytotoxity.

Germinal Center Dendritic Cells Express More ICAM-1 Than Extrafollicular Dendritic Cells and ICAM-1/LFA-1 Interactions are Involved in the Capacity of Dendritic Cells to Induce PBMCs Proliferation

Germinal center dendritic cells (GCDCs) have been identified as CD11c+ CD4+ CD3− cells located in GCs with the ability of inducing marked proliferation of allogenic T cells. Using immunofluorescence techniques, we have observed that this CD11c+ CD4+ CD3− immunophenotype identified GCDCs but also a subset of extrafollicular DCs. By flow cytometry, we were able to discriminate the GCDCs (CD11chigh CD4high lin−) from the other tonsil DCs. By immunofluorescence and flow cytometry, we found that dendritic cells of germinal centers express more intracellular adhesion molecule-1 (ICAM-1) (CD54) than extrafollicular dendritic cells. Proliferation of peripheral blood mononuclear cells (PBMCs) induced by coculture with purified CD11c+ CD4+ CD3− DCs was reduced by addition of blocking anti-CD54 antibodies. In summary, distinct levels of ICAM-1 expression allow the distinction between GCDCs and extrafollicular DCs, and cellular interactions mediated by CD54 are likely to play a role in the capacity of GCDC to stimulate allogenic PBMC proliferation.

Macrophages, Inflammation, and Lung Cancer

Lung cancer is the leading cause of cancer mortality worldwide, and at only 18%, it has one of the lowest 5-year survival rates of all malignancies. With its highly complex mutational landscape, treatment strategies against lung cancer have proved largely ineffective. However with the recent success of immunotherapy trials in lung cancer, there is renewed enthusiasm in targeting the immune component of tumors. Macrophages make up the majority of the immune infiltrate in tumors and are a key cell type linking inflammation and cancer. Although the mechanisms through which inflammation promotes cancer are not fully understood, two connected hypotheses have emerged: an intrinsic pathway, driven by genetic alterations that lead to neoplasia and inflammation, and an extrinsic pathway, driven by inflammatory conditions that increase cancer risk. Here, we discuss the contribution of macrophages to these pathways and subsequently their roles in established tumors. We highlight studies investigating the association of macrophages with lung cancer prognosis and discuss emerging therapeutic strategies for targeting macrophages in the tumor microenvironment.

Multiple Transcriptome Data Analysis Reveals Biologically Relevant Atopic Dermatitis Signature Genes and Pathways

Several studies have identified genes that are differentially expressed in atopic dermatitis (AD) compared to normal skin. However, there is also considerable variation in the list of differentially expressed genes (DEGs) reported by different groups and the exact cause of AD is still not fully understood. Using a rank-based approach, we analyzed gene expression data from five different microarray studies, comprising a total of 127 samples and more than 250,000 transcripts. A total of 89 AD gene expression signatures '89ADGES', including FLG gene, were identified to show dysregulation consistently across these studies. Using a Support Vector Machine, we showed that the '89ADGES' discriminates AD from normal skin with 98% predictive accuracy. Functional annotation of these genes implicated their roles in immune responses (e.g., betadefensin, microseminoprotein), keratinocyte differentiation/epidermal development (e.g., FLG, CORIN, AQP, LOR, KRT16), inflammation (e.g., IL37, IL27RA, CCL18) and lipid metabolism (e.g., AKR1B10, FAD7, FAR2). Subsequently, we validated a subset of signature genes using quantitative PCR in a mouse model. Using a bioinformatic approach, we identified keratinocyte pathway over-represented (P = <0.0006) among the 89 signature genes. Keratinocytes are known to play a major role in barrier function due to their location in the epidermis. Our result suggests that besides immune- mediated pathway, skin barrier pathways such as the keratinocyte differentiation pathway play a key role in AD pathogenesis. A better understanding of the role of keratinocytes in AD will be important for developing novel "barrier therapy" for this disease.