Chemoattractant Cytokines Research Articles

3D Neurovascular Unit Tissue Model to Assess Responses to Traumatic Brain Injury.

The neurovascular unit (NVU) is a critical interface in the central nervous system that links vascular interactions with glial and neural tissue. Disruption of the NVU has been linked to the onset and progression of neurodegenerative diseases. Despite its significance the NVU remains challenging to study in a physiologically relevant manner. Here, a 3D cell triculture model of the NVU is developed that incorporates human primary brain microvascular endothelial cells, astrocytes, and pericytes into a tissue system that can be sustained invitro for several weeks. This tissue model helps recapitulate the complexity of the NVU and can be used to interrogate the mechanisms of disease and cell-cell interactions. The NVU tissue model displays elevated cell death and inflammatory responses following mechanical damage, to emulate traumatic brain injury (TBI) under controlled laboratory conditions, including lactate dehydrogenase (LDH) release, elevated inflammatory markers TNF-α and monocyte chemoattractant cytokines MCP-2 and MCP-3 and reduced expression of the tight junction marker ZO-1. This 3D tissue model serves as a tool for deciphering mechanisms of TBIs and immune responses associated with the NVU.

Single-Cell Analysis Reveals the Cellular and Molecular Changes of Liver Injury and Fibrosis in Mice During the Progression of Schistosoma japonicum Infection

Schistosomiasis is a parasitic disease that poses a serious threat to human health. However, the pathogenic mechanism during the progression of Schistosoma japonicum infection remains unclear. In order to elucidate this mechanism, we used single-cell RNA sequencing (scRNA-seq) to investigate the transcriptome characteristics of the cellular (single-cell) landscape in the livers of mice infected with Schistosoma japonicum, which were divided into three groups: uninfected mice (0 week (w)), infected mice at 6 w post-infection (the acute phase), and infected mice at 10 w post-infection (the chronic phase). A total of 31,847 liver cells were included and clustered into 21 groups. The cells and T-cells had high heterogeneity in the liver during the progression of schistosome infection. The number and intensity of the intercellular interactions significantly increased at 6 w after infection but decreased at 10 w. The inflammatory signaling pathways chemoattractant cytokine ligand (CCL)5-chemokine C-C-motif receptor (CCR)5 between macrophages and T-cells were predominant at 6 w post-infection; the CCL6-CCR2 signaling pathway between macrophages was predominant at 10 w. The CD80 signaling pathway related to T-cell activation was increased at 6 w after infection, and increased expression of its receptor CD28 on the surfaces of CD4+ and CD8+ T-cells was confirmed by flow cytometry, suggesting an increase in their activation. In addition, scRNA-seq and quantitative reverse transcription polymerase chain reaction (qRT-PCR) confirmed that the intercellular communication between secretory phosphoprotein 1 (SPP1)-cluster of differentiation (CD44), insulin-like growth factor (IGF)-1-IGF1r and visfatin-insulin receptor (Insr) associated with bone metabolism and insulin metabolism was increased and enhanced in the liver at 6 w post-infection. Overall, we provide the comprehensive single-cell transcriptome landscape of the liver in mice during the progression of schistosome infection and delineate the key cellular and molecular events involved in schistosome infection-induced liver injury and fibrosis. The elevated CCL5-CCR5 and CCL6-CCR2 signaling pathways in the liver may be a drug target for liver injury and fibrosis caused by schistosome infection, respectively.

A lymphocyte chemoaffinity axis for lung, non-intestinal mucosae and CNS.

Tissue-selective chemoattractants direct lymphocytes to epithelial surfaces to establish local immune environments, regulate immune responses to food antigens and commensal organisms, and protect from pathogens. Homeostatic chemoattractants for small intestines, colon, and skin are known1 2, but chemotropic mechanisms selective for respiratory tract and other non-intestinal mucosal tissues (NIMT) remain poorly understood. Here we leveraged diverse omics datasets to identify GPR25 as a lymphocyte receptor for CXCL17, a chemoattractant cytokine whose expression by epithelial cells of airways, upper gastrointestinal and squamous mucosae unifies the NIMT and distinguishes them from intestinal mucosae. Single-cell transcriptomic analyses show that GPR25 is induced on innate lymphocytes prior to emigration to the periphery, and is imprinted in secondary lymphoid tissues on activated B and T cells responding to immune challenge. GPR25 characterizes B and T tissue resident memory and regulatory T lymphocytes in NIMT and lungs in humans and mediates lymphocyte homing to barrier epithelia of the airways, oral cavity, stomach, biliary and genitourinary tracts in mouse models. GPR25 is also expressed by T cells in cerebrospinal fluid and CXCL17 by neurons, suggesting a role in CNS immune regulation. We reveal widespread imprinting of GPR25 on regulatory T cells, suggesting a mechanistic link to population genetic evidence that GPR25 is protective in autoimmunity3,4. Our results define a GPR25-CXCL17 chemoaffinity axis with the potential to integrate immunity and tolerance at non-intestinal mucosae and the CNS.

CNS-wide repopulation by hematopoietic-derived microglia-like cells corrects progranulin deficiency in mice

Hematopoietic stem cell transplantation can deliver therapeutic proteins to the central nervous system (CNS) through transplant-derived microglia-like cells. However, current conditioning approaches result in low and slow engraftment of transplanted cells in the CNS. Here we optimized a brain conditioning regimen that leads to rapid, robust, and persistent microglia replacement without adverse effects on neurobehavior or hematopoiesis. This regimen combines busulfan myeloablation and six days of Colony-stimulating factor 1 receptor inhibitor PLX3397. Single-cell analyses revealed unappreciated heterogeneity of microglia-like cells with most cells expressing genes characteristic of homeostatic microglia, brain-border-associated macrophages, and unique markers. Cytokine analysis in the CNS showed transient inductions of myeloproliferative and chemoattractant cytokines that help repopulate the microglia niche. Bone marrow transplant of progranulin-deficient mice conditioned with busulfan and PLX3397 restored progranulin in the brain and eyes and normalized brain lipofuscin storage, proteostasis, and lipid metabolism. This study advances our understanding of CNS repopulation by hematopoietic-derived cells and demonstrates its therapeutic potential for treating progranulin-dependent neurodegeneration.

New Perspectives in the Management of Chronic Hand Eczema: Lessons from Pathogenesis.

Chronic hand eczema (CHE) is a common inflammatory skin condition that significantly impacts the quality of life. From work-related disabilities to social embarrassment, pain, and financial costs, the burden on society is substantial. Managing this condition presents challenges such as long-term treatment, poor patient compliance, therapy side effects, and economic feasibility. As a result, significant efforts have been made in this field in recent years. Specifically, the broader understanding of CHE pathogenesis has led to the development of new drugs, both topical and systemic. The aim of this narrative review is to summarize the current available data on hand eczema pathophysiology and explore the resulting developments in drugs for its treatment. A comprehensive search on PubMed and the other main scientific databases was conducted using keywords related to CHE and its pathogenesis. The most relevant pathways targeted by therapies include the JAK-STAT cascade, IL-4, and IL-13 axis, phosphodiesterase 4 enzyme, and chemo-attractant cytokines. In the near future, physicians will have a plethora of therapeutic alternatives. Consequently, they should be well-trained not only in how to use these alternatives but also how to combine these treatments to address the ongoing challenges related to efficacy, tolerability, and safety.

The Effect of PARP Inhibitor Radiosensitization on the mRNA Translational Regulation of T Cell Chemokines

Immunotherapy has modestly improved survival for small cell lung cancer (SCLC) patients. Low response rate and rapid disease progression remain an intractable challenge. One of the factors that contribute to immunotherapy resistance is the lack of cytotoxic T cell infiltration. The expression of chemoattractant cytokines, like CCL5 and CXCL10, are essential for T cell infiltration. The control of chemokine expression is not fully understood, but both transcriptional and translational control pathways could play a major role. Previous studies have shown a correlation between DNA damage and chemokine expression and that PARP inhibitors (PARPi) are radiosensitizers for SCLC that increases DNA damage. The objectives of this study were to define this potential PARPi immunogenic radiosensitizing relationship. We identified doses of olaparib+ radiation treatment (RT) that conferred radiosensitization in SCLC cell-lines by cell viability and/or clonogenic assays. Olaparib+RT induced CCL5 and CXCL10 mRNA expression was measured by qPCR across SCLC cell-lines. Protein level of chemokines was assessed by immunoblotting. SBC5 cells were treated with olaparib+RT and submitted for RNA sequencing analysis. Genes with adjusted p value<0.05 were considered significant. Protein level changes and target gene knock-out (KO) were confirmed by immunoblotting. Chemokine CXCL10 mRNA and protein level in wildtype (WT) and KO cells were measured by qPCR and western blot, respectively. A mRNA decay assay and dual-luciferase reporter assay was used to identify the region of CXCL10 mRNA that confers mRNA stability control. In vivo anti-tumor efficacy and tumor T cell infiltration studies were done in B6129F mice bearing KP1 tumors. And the T cell infiltration was measured by immune profiling. In vitro, olaparib+RT significantly increased CXCL10 mRNA in all four SCLC subtype cell-lines in comparison to vehicle control. Consistently, the increase of CXCL10 protein levels (3-fold) was observed in SBC5 cells. By RNA-Seq, a top-ranking translational repressor was EIF4E2 (4EHP) mRNA. The downregulation of EIF4E2 protein by olaparib+RT was validated in four SCLC subtypes by western blot. EIF4E2 KO in HEK293 and SBC5 cells increased CXCL10 mRNA and protein level. By mRNA decay assay and western blot, the absence of EIF4E2 stabilized CXCL10 mRNA and increased CXCL10 protein levels. The dual-luciferase assay demonstrated EIF4E2 destabilizes CXCL10 mRNA via the 3'UTR of CXCL10. In vivo, immune profiling showed olaparib+RT significantly increased the total T cell and CD8+ T cell infiltration. Finally, anti-PD-L1 inhibition potentiated olaparib + IR to improve tumor control in KP1 allograft. Our study demonstrated olaparib + RT increases CXCL10 protein levels through downregulating EIF4E2 to subsequently increase T cell infiltration. Olaparib + RT enhanced anti-PD-L1 immunotherapy efficacy and has therapeutic potential as an immunogenic radiosensitizer.

Evaluation of salivary Chemerin in oral leukoplakia, oral squamous cell carcinoma and healthy controls

Introduction: Chemerin is a multifunctional chemoattractant cytokine, encoded by RARRES2 gene. Its role in oral carcinogenesis is largely unexplored. Study was undertaken to evaluate the role of salivary chemerin as a potential biomarker in the early diagnosis of oral cancer and to elucidate the clinicopathologic and prognostic significance of chemerin in different grades of Oral Squamous Cell Carcinoma (OSCC) and oral leukoplakia. Materials and Methods: The study comprised 96 subjects, divided into 3 groups, each consisting of 32 subjects. These groups were clinically and histopathologically diagnosed with OSCC, oral leukoplakia, and healthy controls, respectively. The whole unstimulated saliva (1.5 mL) was collected from the subjects using passive drool technique and immediately centrifuged at 3000 rpm for 10 minutes. The salivary chemerin level was estimated using the competitive sandwich enzyme-linked immunosorbent assay method. The statistical analysis was performed using R software EZR version 1.32. Independent t-tests, analysis of variance tests, and Scheffe Multiple Comparisons were carried out to compare quantitative parameters. A receiver operating characteristic (ROC) curve was plotted to assess diagnostic accuracy of salivary chemerin. Results: Significantly higher levels of salivary chemerin were observed in OSCC and oral leukoplakia patients compared to healthy controls (P &lt; 0.05). The study further established an increase in salivary chemerin concentration in different histological grades of OSCC and oral leukoplakia. ROC curve analysis suggested that salivary chemerin is a highly sensitive and specific indicator for early screening and detection of oral leukoplakia and OSCC. Conclusion: Salivary chemerin can be considered as a reliable and specific indicator for the early screening and detection of oral leukoplakia and OSCC and a highly sensitive biomarker which may aid in detection of malignant transformation of oral leukoplakia.

Chemokine Heteromers and Their Impact on Cellular Function—A Conceptual Framework

Chemoattractant cytokines or chemokines are proteins involved in numerous biological activities. Their essential role consists of the formation of gradient and (immune) cell recruitment. Chemokine biology and its related signaling system is more complex than simple ligand–receptor interactions. Beside interactions with their cognate and/or atypical chemokine receptors, and glycosaminoglycans (GAGs), chemokines form complexes with themselves as homo-oligomers, heteromers and also with other soluble effector proteins, including the atypical chemokine MIF, carbohydrate-binding proteins (galectins), damage-associated molecular patterns (DAMPs) or with chemokine-binding proteins such as evasins. Likewise, nucleic acids have been described as binding targets for the tetrameric form of CXCL4. The dynamic balance between monomeric and dimeric structures, as well as interactions with GAGs, modulate the concentrations of free chemokines available along with the nature of the gradient. Dimerization of chemokines changes the canonical monomeric fold into two main dimeric structures, namely CC- and CXC-type dimers. Recent studies highlighted that chemokine dimer formation is a frequent event that could occur under pathophysiological conditions. The structural changes dictated by chemokine dimerization confer additional biological activities, e.g., biased signaling. The present review will provide a short overview of the known functionality of chemokines together with the consequences of the interactions engaged by the chemokines with other proteins. Finally, we will present potential therapeutic tools targeting the chemokine multimeric structures that could modulate their biological functions.

A Novel C-C Chemoattractant Cytokine (Chemokine) Receptor 6 (CCR6) Antagonist (PF-07054894) Distinguishes between Homologous Chemokine Receptors, Increases Basal Circulating CCR6+ T Cells, and Ameliorates Interleukin-23-Induced Skin Inflammation.

Blocking chemokine receptor C-C chemoattractant cytokine (chemokine) receptor (CCR) 6-dependent T cell migration has therapeutic promise in inflammatory diseases. PF-07054894 is a novel CCR6 antagonist that blocked only CCR6, CCR7, and C-X-C chemoattractant cytokine (chemokine) receptor (CXCR) 2 in a β-arrestin assay panel of 168 G protein-coupled receptors. Inhibition of CCR6-mediated human T cell chemotaxis by (R)-4-((2-(((1,4-Dimethyl-1H-pyrazol-3-yl)(1-methylcyclopentyl)methyl)amino)-3,4-dioxocyclobut-1-en-1-yl)amino)-3-hydroxy-N,N-dimethylpicolinamide (PF-07054894) was insurmountable by CCR6 ligand, C-C motif ligand (CCL) 20. In contrast, blockade of CCR7-dependent chemotaxis in human T cells and CXCR2-dependent chemotaxis in human neutrophils by PF-07054894 were surmountable by CCL19 and C-X-C motif ligand 1, respectively. [3H]-PF-07054894 showed a slower dissociation rate for CCR6 than for CCR7 and CXCR2 suggesting that differences in chemotaxis patterns of inhibition could be attributable to offset kinetics. Consistent with this notion, an analog of PF-07054894 with fast dissociation rate showed surmountable inhibition of CCL20/CCR6 chemotaxis. Furthermore, pre-equilibration of T cells with PF-07054894 increased its inhibitory potency in CCL20/CCR6 chemotaxis by 10-fold. The functional selectivity of PF-07054894 for inhibition of CCR6 relative to CCR7 and CXCR2 is estimated to be at least 50- and 150-fold, respectively. When administered orally to naïve cynomolgus monkeys, PF-07054894 increased the frequency of CCR6+ peripheral blood T cells, suggesting that blockade of CCR6 inhibited homeostatic migration of T cells from blood to tissues. PF-07054894 inhibited interleukin-23-induced mouse skin ear swelling to a similar extent as genetic ablation of CCR6. PF-07054894 caused an increase in cell surface CCR6 in mouse and monkey B cells, which was recapitulated in mouse splenocytes in vitro. In conclusion, PF-07054894 is a potent and functionally selective CCR6 antagonist that blocks CCR6-mediated chemotaxis in vitro and in vivo. SIGNIFICANCE STATEMENT: The chemokine receptor, C-C chemoattractant cytokine (chemokine) receptor 6 (CCR6) plays a key role in the migration of pathogenic lymphocytes and dendritic cells into sites of inflammation. (R)-4-((2-(((1,4-Dimethyl-1H-pyrazol-3-yl)(1-methylcyclopentyl)methyl)amino)-3,4-dioxocyclobut-1-en-1-yl)amino)-3-hydroxy-N,N-dimethylpicolinamide (PF-07054894) is a novel CCR6 small molecule antagonist that illustrates the importance of binding kinetics in achieving pharmacological potency and selectivity. Orally administered PF-07054894 blocks homeostatic and pathogenic functions of CCR6, suggesting that it is a promising therapeutic agent for the treatment of a variety of autoimmune and inflammatory diseases.

Abstract 4057: T cells co-expressing a highly potent NY-ESO-1-specific TCR and a chimeric PD1-41BB co-stimulatory switch receptor show a favorable polyfunctional profile for the treatment of solid tumors

Abstract T cell receptor (TCR)-based immunotherapies have shown great potential for the safe and efficacious treatment of patients suffering from various solid malignancies. However, novel strategies are needed to overcome the immunosuppressive tumor microenvironment (TME) and to enhance the efficacy of TCR-T cell (TCR-T) therapies in solid tumors. NY-ESO-1 is a cancer/testis antigen that is highly expressed in various solid tumor indications while its expression in healthy tissues is restricted to male germ cells. Our HLA-A2-restricted, NY-ESO-1-specific TCR used here was selected from a non-tolerized T cell repertoire of a healthy donor using Medigene’s proprietary Allo-HLA TCR priming technology and high-throughput TCR isolation and characterization processes. To prevent inhibition of TCR-T cell function via the PD1-PDL1 axis within the TME, the NY-ESO-1-TCR was co-expressed with a chimeric PD1-41BB co-stimulatory switch receptor, consisting of the extracellular domain of PD1 and the intracellular domain of the 41BB co-stimulatory receptor. Thereby, an inhibitory signal from the PD1-PD-L1 axis is turned into a co-stimulatory one, which results in a dual mechanistic benefit, and superior TCR-T cells with respect to tumor cell killing, cell proliferation and poly-cytokine secretion. Co-expression of PD1-41BB on NY-ESO-1 TCR-T cells led to a 3-fold increase in IFN-γ release and a higher proliferation index (~1.5 fold) (after antigen encounter. Under conditions of repeated antigen exposure in vitro using HLA-A2/NY-ESO-1/PDL1-positive tumor spheroids, TCR-T cells co-expressing PD1-41BB showed enhanced functional activities compared to TCR-T cells carrying the TCR alone. In vitro single-cell secretome analyses demonstrated up to a 5-fold increase in polyfunctional T cells and a higher polyfunctional strength index (PSI) for NY-ESO-1 TCR-T cells expressing PD1-41BB compared to “naked” NY-ESO-1 TCR-T cells lacking PD1-41BB. Typical Th1 cytokines/proteins like IFN-γ, TNF-α and Granzyme B mainly contributed to the superior PSI of NY-ESO-1-TCR-T cells co-expressing PD1-41BB. Importantly, our data indicate that transgenic PD1-41BB has the capacity to provide a co-stimulatory signal despite the presence of endogenous PD1 which is upregulated in stimulated “naked“ NY-ESO-1 TCR-T cells. In summary, we find that co-expression of a chimeric PD1-41BB co-stimulatory switch receptor significantly enhances in vitro NY-ESO-1 TCR-T cell proliferation, functionality and anti-tumor activity. Analyses of single-cell T cell cytokine polyfunctionality helped us to unravel the mode of action of NY-ESO-1 TCR-T cells co-expressing PD1-41BB and point to their complex display of effector, stimulatory and chemoattractant cytokines as a potential driver for superior recognition of tumor cells. Citation Format: Andrea Coluccio, Stefanie Tippmer, Petra Prinz, Maja Buerdek, Kathrin Mutze, Barbara Loesch, Kathrin Davari, Giulia Longinotti, Dolores J. Schendel. T cells co-expressing a highly potent NY-ESO-1-specific TCR and a chimeric PD1-41BB co-stimulatory switch receptor show a favorable polyfunctional profile for the treatment of solid tumors. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4057.

Abstract 5874: HSF1 downregulation of CCL5 reduces CD8 T cell trafficking in breast cancer

Abstract Breast cancer is the leading cause of cancer related deaths in women. The presence of cytotoxic immune cells, specifically CD8+ T cells, in breast tumors is associated with better patient outcomes. Our goal is to understand mechanisms that regulate the infiltration of CD8+ T cells. This will in turn, improve the treatment and enhance patient overall survival. Utilizing a novel HSF1 activity gene signature, we observed that HSF1 activity was negatively associated with the presence of CD8+ T cells in breast cancer patients. Both CIBERSORT analysis of TCGA data as well as direct assessment of patient primary specimens demonstrated that patient tumors with high HSF1 activity had lower numbers of CD8+ T cells. To functionally test this relationship, HSF1 was knocked down in 4T1 breast cancer cells and grown orthotopically in BALB/c mice. Tumors with HSF1 knockdown showed lower tumor volumes and increased CD8+ T cell infiltration. We subjected the control and knockdown tumors to single- cell RNA sequencing analysis and found increased immune cell presence specifically CD8+ T cell presence in knockdown tumors. We further tested the effect of CD8+ T cells on the growth of HSF1 knockdown tumors by depleting CD8+ T cells in BALB/c mice. HSF1 knockdown tumors were significantly larger with CD8+ T cell depletion suggesting a functional role for HSF1 to inhibit CD8+ T cell infiltration and protect the tumor from immune-mediated killing. To investigate the mechanism by which HSF1 affects CD8+ T cells, we investigated whether HSF1 affects chemotactic cytokines. We found that loss of HSF1 significantly increased secretion of CCL5, a known chemoattractant for CD8+ T cells. Loss of HSF1 also increased mRNA levels of CCL5, suggesting a transcriptional effect on CCL5. To test the importance of CCL5 in the phenotype of HSF1 knockdown, a transwell migration assay was performed wherein T cells from BALB/c mice were placed in the upper chamber of a transwell chamber and the lower chamber contained conditioned medium from 4T1 cells with knockdown of HSF1 with or without knockdown of CCL5. The lower chamber was subjected to flow cytometry for CD3/CD8 to identify CD8+ T cells and we observed that loss of HSF1 increased migration of CD8+ T cells and this was ablated with additional loss of CCL5. These results suggest CCL5 is a significant mediator for the recruitment of CD8+ T cells when HSF1 is lost in cancer cells. We propose the model whereby high HSF1 activity in breast cancer cells suppresses expression and secretion of the chemo-attractant cytokine CCL5 that ultimately leads to a decrease in CD8+ T cells in breast tumors microenvironment. Citation Format: Curteisha LeeAnn Jacobs, Sakhi Shah, Wen-Cheng Lu, Richard Carpenter, Haimanti Ray, Xin Lu, Sha Cao. HSF1 downregulation of CCL5 reduces CD8 T cell trafficking in breast cancer. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5874.

Galectin-1 mediates interactions between polymorphonuclear leukocytes and vascular endothelial cells, and promotes their extravasation during lipopolysaccharide-induced acute lung injury.

The lung airway epithelial surface is heavily covered with sialic acids as the terminal carbohydrate on most cell surface glycoconjugates and can be removed by microbial neuraminidases or endogenous sialidases. By desialylating the lung epithelial surface, neuraminidase acts as an important virulence factor in many mucosal pathogens, such as influenza and S. pneumoniae. Desialylation exposes the subterminal galactosyl moieties - the binding glycotopes for galectins, a family of carbohydrate-recognition proteins playing important roles in various aspects of immune responses. Galectin-1 and galectin-3 have been extensively studied in their roles related to host immune responses, but some questions about their role(s) in leukocyte recruitment during lung bacterial infection remain unanswered. In this study, we found that both galectin-1 and galectin-3 bind to polymorphonuclear leukocytes (PMNs) and enhance the interaction of endothelial intercellular adhesion molecule-1 (ICAM-1) with PMNs, which is further increased by PMN desialylation. In addition, we observed that in vitro galectin-1 mediates the binding of PMNs, particularly desialylated PMNs, onto the endothelial cells. Finally, in a murine model for LPS-mediated acute lung injury, we observed that galectin-1 modulates PMN infiltration to the lung without altering the expression of chemoattractant cytokines. We conclude that galectins, particularly galectin-1, may function as adhesion molecules that mediate PMN-endothelial cell interactions, and modulate PMN infiltration during acute lung injury.

Curcumin and chemokines: mechanism of action and therapeutic potential in inflammatory diseases.

Chemokines belong to the family of cytokines with chemoattractant properties that regulate chemotaxis and leukocyte migration, as well as the induction of angiogenesis and maintenance of hemostasis. Curcumin, the major component of the Curcuma longa rhizome, has various pharmacological actions, including anti-inflammatory, immune-regulatory, anti-oxidative, and lipid-modifying properties. Chemokines and chemokine receptors are influenced/modulated by curcumin. Thus, the current review focuses on the molecular mechanisms associated with curcumin's effects on chemoattractant cytokines, as well as putting into context the many studies that have reported curcumin-mediated regulatory effects on inflammatory conditions in the organs/systems of the body (e.g., the central nervous system, liver, and cardiovascular system). Curcumin's effects on viral and bacterial infections, cancer, and adverse pregnancy outcomes are also reviewed.

Revisiting the Role of the CXCL13/CXCR5-Associated Immune Axis in Melanoma: Potential Implications for Anti-PD-1-Related Biomarker Research.

CXCL13 is a potent chemoattractant cytokine that promotes the migration of cells expressing its cognate receptor, CXCR5. Accordingly, T follicular helper cells and B cells migrate towards B cell follicles in lymph nodes, where the resulting spatial proximity promotes B cell/T cell interaction and antibody formation. Moreover, effector cells of the CXCL13/CXCR5-associated immune axis express PD-1, with corresponding circulating cells occurring in the blood. The formation of so-called ectopic or tertiary lymphoid structures, recently detected in different cancer types, represents an integral part of this axis, particularly in the context of its emerging role in anti-tumor defense. These aspects of the CXCL13/CXCR5-associated immune axis are highlighted in this review, which focuses on cutaneous malignant melanoma. Specifically, we elaborate on the role of this important immune axis as a possible ancillary target of immune checkpoint inhibition with anti-PD-1 antibodies in different therapeutic settings and as a potential source of predictive biomarkers regarding treatment efficacy.

Evaluation of the Immunomodulatory Effects of a Probiotics and Natural Extract-Based Formulation in Bacterial-Induced Prostatitis.

Among the many factors inducing prostate inflammation, bacterial contribution is potentially underrated according to the scientific community. Bacterial prostatitis is characterized by modifications of the prostatic microenvironment, mainly driven by the immune system. Macrophages play a major role in bacterial prostatitis, secreting a plethora of proinflammatory and chemoattractive cytokines and proteolytic enzymes able to degrade the ECM, so facilitating the invasion of other immune cells. Consequently, macrophages represent a link between bacterial infection and prostate inflammation, as well as being the main target of prostate anti-inflammatory drugs and dietary supplements. This study aims to investigate the effect of a formulation composed of active principles and a probiotic strain with a particular focus on the anti-inflammatory effect in an in vitro bacterial prostatitis model. The results obtained showed that the formulation reduces the inflammatory response of prostatic epithelium induced by bacterial infection. This effect is mediated by the modulation of activated macrophages. Analysis of the cytokines released highlights that the tested formulation is able to reduce the expression of key proinflammatory cytokines involved in the pathogenesis of prostate diseases, in particular prostate cancer, and represents a valuable tool to prevent bacterial prostatitis and ensure favorable prostate health.

Extracellular Vesicle-Associated TWEAK Contributes to Vascular Inflammation and Remodeling During Acute Cellular Rejection

Acute cellular rejection (ACR) is a leading cause of graft loss and death after heart transplantation despite effective immunosuppressive therapies. The identification of factors that impair graft vascular barrier function or promote immune cell recruitment during ACR could provide new therapeutic opportunities for the treatment of patients who receive transplants. In 2 ACR cohorts, we found theextracellular vesicle-associated cytokine TWEAK to be elevated during ACR. Vesicular TWEAK promoted expression of proinflammatory genes and the release of chemoattractant cytokines from human cardiac endothelial cells. We conclude that vesicular TWEAK is a novel target with potential therapeutic implications in ACR.

Interaction networks and pathway analysis of genetic resistance to gastrointestinal nematodes in sheep.

Gastrointestinal nematode (GINs) infections are one of the causative agents of health and economic issues in sheep production systems worldwide. Considerable genetic variations in resistance or susceptibility in different sheep breeds are documented, but published results are conflicting. Recent advances obtained by high-throughput technologies such as commercial SNP chips, whole-genome sequencing, or whole transcriptome profiling provide new insights into breeding for host resistance or nematode control at the genetic levels. This study aimed to identify potential biomarkers associated with the resistance to ovine GINs through a network analysis approach. Comprehensive gene and protein interaction networks were reconstructed for candidate genes involved in the most related immune pathways associated with resistance to ovine GINs using data mining from literature. Generally, 30 genes including CD53, CHIA, RELN, HRH1, EPS15, LRP8, ATP2B1, IL4, IL5, IL13, IL2RA, IL23R, TNFα, IFNγ, TBX21, SH3RF1, HERC2, PTPN1, BIN1, HERC5, C3AR1, NOS2, STAT5B, STAT4, CCL1, CCL8, VIL1, CXCR1, CXCR2, and CXCR4 located on chromosomes 1, 2, 3, 4, 5, 6, 11, 13, 19, and 20 have been found as containing effective regions with the most related pathways to nematode infections. The results obtained by network analysis showed two functional modules, belonging to the interleukins family (IL4, IL5, IL13, IL23R, and IL2RA) and chemokine receptors or ligands family (CXCR1, CXCR2, CXCR4, CCL1, and CCL8). Interleukins are a group of cytokines that are expressed by white blood cells with a major role in the immune system. Chemokines are also a family of chemoattractant cytokines which play a vital role in cell migration that influence the immune system by a process known as chemotaxis. The results provide useful information for the functional annotation of candidate genes related to parasite resistance and add new information towards a consensus on quantitative trait loci (QTLs) related to the incidence of nematode infections.

Investigating the role of tau loss‐of‐function in Alzheimer’s Disease pathogenesis

AbstractBackgroundOne hallmark of Alzheimer’s Disease (AD) pathology is hyperphosphorylation of tau protein, which leads to loss of its normal function and promotes aggregation into neurotoxic fibrillary tangles. While tau gain‐of‐toxic function is well‐documented, the exact role of tau loss‐of‐function in AD pathogenesis remains uncharacterized. We hypothesize that tau loss‐of‐function contributes to AD pathogenesis by activating the cellular stress response in neurons and astrocytes, characterized by cytoplasmic double‐stranded RNA (dsRNA) release, stress granule formation, and inflammation.MethodWe generated human induced pluripotent stem cell (hiPSC)‐derived mixed cortical cultures and primary human fetal astrocyte cultures, allowing us to model the earliest stages of AD pathogenesis in a uniquely human system. In these cultures, we depleted tau through lentiviral transduction and CRISPR‐Cas9 to model acute and chronic loss‐of‐function, respectively. We utilized quantitative real‐time polymerase chain reactions, enzyme‐linked immunosorbent assays, and immunocytochemistry to investigate the expression of genes and proteins implicated in stress and inflammation.ResultPreliminary results indicate upregulation of genes and proteins associated with inflammation and stress granule formation in tau‐depleted neurons and astrocytes. Tau‐depleted cortical cultures exhibit increased secretion of chemoattractant cytokines, and tau‐depleted astrocytes demonstrate increased glial fibrillary acidic protein expression suggestive of non‐cell autonomous pro‐inflammatory cytokine induction. Further, tau‐depleted neurons show increased levels of stress chaperones and cytoplasmic dsRNA known to induce stress granules.ConclusionTau loss‐of‐function may contribute to AD pathogenesis through promoting the release of double‐stranded RNA into the cytoplasm, stress granule formation, and inflammation.

Beneficial effects of CCL8 inhibition at lipopolysaccharide-induced lung injury.

CCL8 (MCP-2) is a chemoattractive cytokine associated with various immune-related pathologies. Recent studies show that CCL8 is significantly stimulated during acute respiratory distress syndrome in severely ill patients with COVID-19, making the inhibition of CCL8 activity a promising treatment. Lipopolysaccharide (LPS)-induced lung injury was evaluated in mice using a neutralizing antibody (1G3E5) against human CCL8. Pharmacokinetic studies indicated that following IP administration, 1G3E5 was sustained at higher levels and for a longer period compared to IV administration. CCL8 expression in the lungs was not enhanced by LPS, but CCR2 and CCR5 receptors were significantly stimulated. 1G3E5-mediated inhibition of CCL8 was associated with the reduction of pulmonary inflammation and suppression of various pro-inflammatory cytokines. These results point to a previously unrecognized, permissive role for CCL8 in mediating cytokine induction and ultimately sustaining inflammation. Disruption of CCL8 activity may provide a strategy for mitigating pulmonary inflammation during lung injury when related to abnormal cytokine induction.

Immediate and Sustained Effects of Cobalt and Zinc-Containing Pigments on Macrophages.

Pigments are among the oldest nanoparticulate products known to mankind, and their use in tattoos is also very old. Nowadays, 25% of American people aged 18 to 50 are tattooed, which poses the question of the delayed effects of tattoos. In this article, we investigated three cobalt [Pigment Violet 14 (purple color)] or cobalt alloy pigments [Pigment Blue 28 (blue color), Pigment Green 14 (green color)], and one zinc pigment [Pigment White 4 (white color)] which constitute a wide range of colors found in tattoos. These pigments contain microparticles and a significant proportion of submicroparticles or nanoparticles (in either aggregate or free form). Because of the key role of macrophages in the scavenging of particulate materials, we tested the effects of cobalt- and zinc-based pigments on the J774A.1 macrophage cell line. In order to detect delayed effects, we compared two exposure schemes: acute exposure for 24 hours and an exposure for 24 hours followed by a 3-day post-exposure recovery period. The conjunction of these two schemes allowed for the investigation of the delayed or sustained effects of pigments. All pigments induced functional effects on macrophages, most of which were pigment-dependent. For example, Pigment Green 19, Pigment Blue 28, and Pigment White 4 showed a delayed alteration of the phagocytic capacity of cells. Moreover, all the pigments tested induced a slight but significant increase in tumor necrosis factor secretion. This effect, however, was transitory. Conversely, only Pigment Blue 28 induced both a short and sustained increase in interleukin 6 secretion. Results showed that in response to bacterial stimuli (LPS), the secretion of tumor necrosis factor and interleukin 6 declined after exposure to pigments followed by a recovery period. For chemoattractant cytokines (MCP-1 or MIP-1α), delayed effects were observed with a secretion decreased in presence of Pigment Blue 28 and Pigment violet 14, both with or without LPS stimuli. The pigments also induced persisting changes in some important macrophage membrane markers such as CD11b, an integrin contributing to cell adhesion and immunological tolerance. In conclusion, the pigments induced functional disorders in macrophages, which, in some cases, persist long after exposure, even at non-toxic doses.