Expression Of CCL21 Research Articles

Epicatechin suppresses the expression of C-C motif chemokine ligand 19 and ameliorates periodontitis

Periodontitis is a prevalent chronic inflammatory disease requiring the development of drug-based therapies. Epicatechin is a major polyphenol in cocoa extract and possesses numerous pharmacological properties. This study aimed to investigate the suppressive effect of epicatechin on C-C motif chemokine ligand 19 (CCL19)-mediated periodontitis using a mouse model. CCL19 expression was high in mouse gingiva with ligature-induced periodontitis. CCL19 expression was increased by lipopolysaccharide stimulation in murine gingival fibroblasts ESK-1 cells, and CCL19 induced the production of tumor necrosis factor alpha and interleukin-1 beta in mouse macrophage-like RAW264.7 cells. Importantly, lipopolysaccharide-enhanced CCL19 expression in ESK-1 cells was significantly suppressed by pretreatment with epicatechin. In addition, epicatechin administration significantly reduced alveolar bone resorption, and expression of Ccl19 and proinflammatory cytokines in the inflamed gingiva in high-fat diet-fed mice. These results demonstrate that epicatechin protects against periodontitis by reducing CCL19 levels, which may be a promising countermeasure for periodontitis in clinical practice.

Dominant immune tolerance in the intestinal tract imposed by RelB-dependent migratory dendritic cells regulates protective type 2 immunity

Dendritic cells (DCs) are crucial for initiating protective immune responses and have also been implicated in the generation and regulation of Foxp3+ regulatory T cells (Treg cells). Here, we show that in the lamina propria of the small intestine, the alternative NF-κB family member RelB is necessary for the differentiation of cryptopatch and isolated lymphoid follicle-associated DCs (CIA-DCs). Moreover, single-cell RNA sequencing reveals a RelB-dependent signature in migratory DCs in mesenteric lymph nodes favoring DC-Treg cell interaction including elevated expression and release of the chemokine CCL22 from RelB-deficient conventional DCs (cDCs). In line with the key role of CCL22 to facilitate DC-Treg cell interaction, RelB-deficient DCs have a selective advantage to interact with Treg cells in an antigen-specific manner. In addition, DC-specific RelB knockout animals show increased total Foxp3+ Treg cell numbers irrespective of inflammatory status. Consequently, DC-specific RelB knockout animals fail to mount protective Th2-dominated immune responses in the intestine after infection with Heligmosomoides polygyrus bakeri. Thus, RelB expression in cDCs acts as a rheostat to establish a tolerogenic set point that is maintained even during strong type 2 immune conditions and thereby is a key regulator of intestinal homeostasis.

Identification of novel hub genes and immune infiltration in atopic dermatitis using integrated bioinformatics analysis

The aim of this study was to identify key genes and investigate the immunological mechanisms of atopic dermatitis (AD) at the molecular level via bioinformatics analysis. Gene expression profiles (GSE32924, GSE107361, GSE121212, and GSE230200) were obtained for screening common differentially expressed genes (co-DEGs) from the gene expression omnibus database. Functional enrichment analysis, protein–protein interaction network and module construction, and identification of common hub genes were performed. Hub genes were validated using receiver operating characteristic curve analysis based on GSE130588 and GSE16161. NetworkAnalyst was used to detect microRNAs (miRNAs) and transcription factors (TFs) associated with the hub genes. The immune cell infiltration was analyzed using the CIBERSORT algorithm to further analyze the correlation between hub genes and immune cells. A total of 146 co-DEGs were obtained, showing significant enrichment in cytokine–cytokine receptor interaction and JAK-STAT signaling pathway. Seven hub genes were identified by Cytoscape and validated with external datasets. Subsequent prediction of miRNAs and TFs targeting these hub genes revealed their regulatory roles. Analysis of immune cell infiltration and correlation revealed a significant positive correlation between CCL22 expression and the number of dendritic cells activated. The identified hub genes represent potential diagnostic and therapeutic targets in the immunological pathogenesis of AD.

Assessment of baseline CCL19+ dendritic cell infiltration for predicting responses to immunotherapy in lung adenocarcinoma patients

To explore the correlation of baseline CCL19+ dendritic cell (CCL19+ DC) infiltration in lung adenocarcinoma microenvironment with immunotherapy efficacy and CD8+ T cell infiltration. We retrospectively analyzed the data of patients with lung adenocarcinoma hospitalized at First Affiliated Hospital of Henan University of Science and Technology from January, 2020 to December, 2023, and collected tissue samples from 96 patients undergoing immunotherapy for assessing CCL19+ DC and CD8+ T cell infiltration using immunofluorescence assay. We evaluated the predictive value of baseline CCL19+ DCs for patient responses to immunotherapy using receiver-operating characteristics (ROC) curves and analyzed the correlations of baseline CCL19+ DC expression with immunotherapy efficacy and CD8+ T cell and cytotoxic T lymphocyte (CTL) infiltrations. In co-culture systems of lung adenocarcinoma PC9 cells, CD8+ T cells and DCs (overexpressing CCL19 with or without anti PD-1 antibody treatment), the expressions of granzyme B, perforin, IFN-γ, and Ki-67 in T cells were analyzed using flow cytometry. The patients with partial or complete remission following immunotherapy had a significantly higher baseline CCL19+ DC infiltration level in lung adenocarcinoma tissues than those with poor responses. CCL19+ DC infiltration had an area under ROC curve of 0.785, a sensitivity of 75.6%, and a specificity of 62.8% for predicting immunotherapy efficacy. The expression of CD8+ T cell surface molecules Granzyme B (P<0.01), Perforin (P<0.01), IFN-γ (P<0.01) and Ki-67 (P<0.001) in patients with high expression of CCL19+ DC were higher than those in patients with low expression of CCL19+ DC. The baseline CCL19+ DC infiltration level was positively correlated with immunotherapy efficacy (P=0.003), CTL infiltration of (r=0.6657, P<0.001) and CD8+ T cell infiltration (P=0.007). In the co-cultured cells, CCL19 overexpression combined with anti-PD1 treatment of the DCs more strongly enhanced cytotoxicity and proliferation of CD8+ T lymphocytes than either of the single treatments (P<0.01 or 0.001). The baseline CCL19+ DC infiltration level in lung adenocarcinoma microenvironment is positively correlated with immunotherapy efficacy and CTL infiltration and can thus predict the response to immunotherapy.

Evaluation of the CCL17/CCL22-CCR4 axis in pediatrics with B-cell acute lymphoblastic leukemia before and after a chemotherapy course

AimsAcute lymphoblastic leukemia (ALL) is the most common type of pediatrics cancer. Chemokines exert different roles in leukemia process through leukocyte recruitment and regulation of disease severity. Due to the prominent roles of chemokine/receptor axes, this study aimed to measure the blood expression levels of CCR4 and their ligands in pediatrics with B-cell ALL (B-ALL). We also evaluated the impact of cytotoxic chemotherapy on this axis. Material and MethodThirty children suffering from B-ALL were included in the study and followed up for 30 days after completion of a chemotherapy course. The blood sampling was performed before and after chemotherapy. 30 healthy donors have also entered the study as control subjects. The mRNA expression of CCL17, CCL22 and CCR4 genes was determined by quantitative real-time PCR. The frequency of the peripheral blood mononuclear cells expressing CCR4 (CCR4 + PBMCs) was also evaluated by the flow cytometry method. Moreover, we evaluated the association of the CCL17/CCL22-CCR4 axis with some diagnostic, prognostic and predictive biomarkers in ALL patients. ResultsThere was overexpression of the CCL17/CCL22-CCR4 axis along with lactate dehydrogenase (LDH) in pediatrics with B-ALL compared to healthy controls. After induction of chemotherapy, the blood expression levels of the CCL17/CCL22-CCR4 axis have reached the levels of healthy controls. The findings for the blood expression levels of CCR4 were also confirmed using flow cytometry. ConclusionThe CCL17/CCL22-CCR4 axis can be used as a novel predictive and prognostic biomarker in B-ALL.

Muscle cell-derived Ccl8 is a negative regulator of skeletal muscle regeneration.

Skeletal muscles undergo robust regeneration upon injury, and infiltrating immune cells play a major role in not only clearing damaged tissues but also regulating the myogenic process through secreted cytokines. Chemokine C-C motif ligand 8 (Ccl8), along with Ccl2 and Ccl7, has been reported to mediate inflammatory responses to suppress muscle regeneration. Ccl8 is also expressed by muscle cells, but a role of the muscle cell-derived Ccl8 in myogenesis has not been reported. In this study, we found that knockdown of Ccl8, but not Ccl2 or Ccl7, led to increased differentiation of C2C12 myoblasts. Analysis of existing single-cell transcriptomic datasets revealed that both immune cells and muscle stem cells (MuSCs) in regenerating muscles express Ccl8, with the expression by MuSCs at a much lower level, and that the temporal patterns of Ccl8 expression were different in MuSCs and macrophages. To probe a function of muscle cell-derived Ccl8 invivo, we utilized a mouse system in which Cas9 was expressed in Pax7+ myogenic progenitor cells (MPCs) and Ccl8 gene editing was induced by AAV9-delivered sgRNA. Depletion of Ccl8 in Pax7+ MPCs resulted in accelerated muscle regeneration after barium chloride-induced injury in both young and middle-aged mice, and intramuscular administration of a recombinant Ccl8 reversed the phenotype. Accelerated regeneration was also observed when Ccl8 was depleted in Myf5+ or MyoD+ MPCs by similar approaches. Our results suggest that muscle cell-derived Ccl8 plays a unique role in regulating the initiation of myogenic differentiation during injury-induced muscle regeneration.

CCL17 and CCL19 are markers of disease progression in alveolar echinococcosis

ObjectivesAlveolar echinococcosis (AE) represents one of the deadliest helminthic infections, characterized by an insidious onset and high lethality. MethodsThis study utilized the Gene Expression Omnibus (GEO) database, applied Weighted Correlation Network Analysis (WGCNA) and Differential Expression Analysis (DEA), and employed the Matthews Correlation Coefficient (MCC) to identify CCL17 and CCL19 as key genes in AE. Immunohistochemistry and immunofluorescence co-localization techniques were used to examine the expression of CCL17 and CCL19 in liver tissue lesions of AE patients. Additionally, a mouse model of multilocular echinococcus larvae infection was developed to study the temporal expression patterns of these genes, along with liver fibrosis and inflammatory responses. ResultsThe in vitro model simulating echinococcal larva infection mirrored the hepatic microenvironment post-infection with multilocular echinococcal tapeworms. Quantitative RT-PCR analysis showed that liver fibrosis occurred in AE patients, with proximal activation and increased expression of CCL17 and CCL19 over time post-infection. Notably, expression peaked during the late stages of infection. Similarly, F4/80, a macrophage marker, exhibited corresponding trends in expression. Upon stimulation of normal hepatocytes by vesicular larvae in cellular experiments, there was a significant increase in CCL17 and CCL19 expression at 12 h post-infection, mirroring the upregulation observed with F4/80. ConclusionCCL17 and CCL19 facilitate macrophage aggregation via the chemokine pathway and their increased expression correlates with the progression of infection, suggesting their potential as biomarkers for AE progression.

CCL22 Induces the Polarization of Immature Dendritic Cells into Tolerogenic Dendritic Cells in Radiation-Induced Lung Injury through the CCR4-Dectin2-PLC-γ2-NFATC2-Nr4a2-PD-L1 Signaling Pathway.

Recruitment of immune cells to the injury site plays a pivotal role in the pathology of radiation-associated diseases. In this study, we investigated the impact of the chemokine CCL22 released from alveolar type II epithelial (AT2) cells after irradiation on the recruitment and functional changes of dendritic cells (DCs) in the development of radiation-induced lung injury (RILI). By examining changes in CCL22 protein levels in lung tissue of C57BL/6N mice with RILI, we discovered that ionizing radiation increased CCL22 expression in irradiated alveolar AT2 cells, as did MLE-12 cells after irradiation. A transwell migration assay revealed that CCL22 promoted the migration of CCR4-positive DCs to the injury site, which explained the migration of pulmonary CCR4-positive DCs in RILI mice invivo. Coculture experiments demonstrated that, consistent with the response of regulatory T cells in the lung tissue of RILI mice, exogenous CCL22-induced DCs promoted regulatory T cell proliferation. Mechanistically, we demonstrated that Dectin2 and Nr4a2 are key targets in the CCL22 signaling pathway, which was confirmed in pulmonary DCs of RILI mice. As a result, CCL22 upregulated the expression of PD-L1, IL-6, and IL-10 in DCs. Consequently, we identified a mechanism in which CCL22 induced DC tolerance through the CCR4-Dectin2-PLC-γ2-NFATC2-Nr4a2-PD-L1 pathway. Collectively, these findings demonstrated that ionizing radiation stimulates the expression of CCL22 in AT2 cells to recruit DCs to the injury site and further polarizes them into a tolerant subgroup of CCL22 DCs to regulate lung immunity, ultimately providing potential therapeutic targets for DC-mediated RILI.

LINC00472 suppresses non-small cell lung cancer progression via regulating miR-23a-3p/CCL22 axis.

Long non-coding RNA (lncRNA) LINC00472 has a close connection with the development of tumors. The aim was to explore the role of LINC00472 on NSCLC cell biological function in vivo and its potential mechanisms. The mRNA levels of LncRNA 00472 and microRNA-23a-3p, were determined by RT-qPCR. Cell Counting Kit-8, cell scratches and western blot assays were used to analyze the proliferation, migration and level of apoptosis-associated proteins. Luciferase reporter assay validates the binding between LINC00472/CCL22 and miR-23a-3p. LINC00472 and CCL22 were lowly expressed in NSCLC tissues and cells, while miR-23a-3p expression was upregulated. LINC00472 overexpression significantly depressed NSCLC cell cellular behavior, whereas promoting cell death. MiR-23a-3p could reverse these above-mentioned biological behavior changes caused by LINC00472 overexpression. Additionally, LINC00472 increased CCL22 expression through sponging miR-23a-3p. Knocking down CCL22 antagonized the inhibitory effect of LINC00472 on NSCLC cell survival. LINC00472 may reduce the cellular growth, and accelerate death of NSCLC through increasing CCL22 expression by targeting miR-23a-3p.

Orally administered yeast-derived β-glucan alleviates mast cell-dependent airway hyperresponsiveness and inflammation in a murine model of asthma.

Particulate β-glucans (WGP) are natural compounds with regulatory roles in various biological processes, including tumorigenesis and inflammatory diseases such as allergic asthma. However, their impact on mast cells (MCs), contributors to airway hyperresponsiveness (AHR) and inflammation in asthma mice, remains unknown. C57BL/6 mice underwent repeated OVA sensitization without alum, followed by Ovalbumin (OVA) challenge. Mice received daily oral administration of WGP (OAW) at doses of 50 or 150 mg/kg before sensitization and challenge. We assessed airway function, lung histopathology, and pulmonary inflammatory cell composition in the airways, as well as proinflammatory cytokines and chemokines in the bronchoalveolar lavage fluid (BALF). The 150 mg/kg OAW treatment mitigated OVA-induced AHR and airway inflammation, evidenced by reduced airway reactivity to aerosolized methacholine (Mch), diminished inflammatory cell infiltration, and goblet cell hyperplasia in lung tissues. Additionally, OAW hindered the recruitment of inflammatory cells, including MCs and eosinophils, in lung tissues and BALF. OAW treatment attenuated proinflammatory tumor necrosis factor (TNF)-α and IL-6 levels in BALF. Notably, OAW significantly downregulated the expression of chemokines CCL3, CCL5, CCL20, CCL22, CXCL9, and CXCL10 in BALF. These results highlight OAW's robust anti-inflammatory properties, suggesting potential benefits in treating MC-dependent AHR and allergic inflammation by influencing inflammatory cell infiltration and regulating proinflammatory cytokines and chemokines in the airways.

Role of estrogen signaling in fibroblastic reticular cellsfor innate and adaptive immune responses in antigen-induced arthritis.

Women are more prone to develop rheumatoid arthritis, with peak incidence occurring around menopause. Estrogen has major effects on the immune system and is protective against arthritis. We have previously shown that treatment with estrogen inhibits inflammation and joint destruction in murine models of arthritis, although the mechanisms involved remain unclear. Fibroblastic reticular cells (FRCs) are specialized stromal cells that generate the three-dimensional structure of lymph nodes (LNs). FRCs are vital for coordinating immune responses from within LNs and are characterized by the expression of the chemokine CCL19, which attracts immune cells. The aim of this study was to determine whether the influence of estrogen on innate and adaptive immune cells in arthritis is mediated by estrogen signaling in FRCs. Conditional knockout mice lacking estrogen receptor α (ERα) in CCL19-expressing cells (Ccl19-CreERαfl/fl) were generated and tested. Ccl19-CreERαfl/fl mice and littermate controls were ovariectomized, treated with vehicle or estradiol and subjected to the 28-day-long antigen-induced arthritis model to enable analyses of differentiated T- and B-cell populations and innate cells in LNs by flow cytometry. The results reveal that while the response to estradiol treatment in numbers of FRCs per LN is significantly reduced in mice lacking ERα in FRCs, estrogen does not inhibit joint inflammation or markedly affect immune responses in this arthritis model. Thus, this study validates the Ccl19-CreERαfl/fl strain for studying estrogen signaling in FRCs within inflammatory diseases, although the chosen arthritis model is deemed unsuitable for addressing this question.

Chemokine CCL19 and Its Receptors CCR7 and CCRL1 in Chronic Rhinosinusitis.

CCL19 has been shown to predict disease severity in COVID-19 and treatment response in rheumatoid arthritis. CCL19 can exert both pro- and anti-inflammatory effects and is elevated in chronic rhinosinusitis (CRS). However, its role in CRS remains unknown. This study sought to determine the transcriptional changes in CCL19, its receptors, and associated cytokines and their association with disease severity in CRS. A clinical database of control subjects and patients with CRS was examined. Lund-Kennedy, Lund-Mackay, Sinonasal Outcomes Test 22 (SNOT-22), and rhinosinusitis disability index (RSDI) scores were collected at enrollment. mRNA was extracted from sinonasal tissues and subjected to multiplex gene expression analysis. Gene transcript differences between patients with CRS and controls were compared and correlated with disease severity metrics. Immunohistochemical analyses of CCL19, CCR7, and CCRL1 were conducted to compare differences in protein expression between cohorts. A subgroup analysis was performed to compare transcriptional and protein expression difference between patients with (CRSwNP) and without (CRSsNP) nasal polyps and controls. Thirty-eight subjects (control group, n=7; CRS group, n=31) were included in this study. CCRL1 (p=0.0093) and CCR7 (p=0.017) levels were significantly elevated in CRS compared to those in controls. CCL19 (p=0.038) and CCR7 (p=0.0097) levels were elevated in CRSwNP and CCRL1 was elevated in CRSsNP (p=0.0004). CCR7 expression was significantly elevated in sinonasal epithelial cells in CRSwNP (p=0.04). CCL19 expression was positively correlated with TNFA expression (p<0.0002). CCL19 and CCR7 expression was positively correlated with SNOT-22 and RSDI scores (p<0.05). CCL19 and CCR7 may modulate TNF-α-driven pro-inflammatory signaling and contribute to increased disease severity in CRS. Mechanistic studies are required to further elucidate the role of CCRL1 in CRS.

Transcriptomic analysis reveals the critical role of chemokine signaling in the anti-atherosclerosis effect of Xuefu Zhuyu decoction

Ethnopharmacological relevanceThe process of atherosclerosis (AS) is complicated. Transcriptomics technology can assist in discovering the underlying mechanisms and exploring the key targets of Traditional Chinese Medicine (TCM) against atherosclerosis. AimThis study aimed to investigate targets and signaling pathways significantly related to AS and the potential intervention targets of Xuefu Zhuyu decoction by transcriptomics. Materials and methodsAS models were established by subjecting ApoE-/-mice to an 8-week high-fat diet. Structural changes and plaque formation in the aortic root were observed using hematoxylin-eosin staining (HE staining), while Oil Red O staining was employed to visualize lipid deposition within the aortic root plaque. Movat staining and immunohistochemical staining were conducted to examine the components present in the aortic root plaque. Macrophage content within the plaque was observed through immunofluorescence. Additionally, mRNA sequencing was performed on aortic tissues to identify differentially expressed genes. Enrichment analysis was performed using GO and KEGG analysis. Visualization of the protein-protein interaction (PPI) network was achieved using Cytoscape 3.7.1 and STRING. Western blotting (WB) was employed to assess the protein expression of major differentially expressed genes in the aortic tissue. The drug freeze-dried powder of Xuefu Zhuyu decoction was prepared and the RAW264.7 cells were induced by lipopolysaccharide (LPS) to build an in vitro model. Real-time quantitative PCR was employed to measure the mRNA expression of major differential genes. ResultsAfter ApoE-/- mice were fed with an 8-week high-fat diet, observable changes included the thinning of the aortic root wall, the accumulation of foam cells within the plaque, and the formation of cholesterol crystals in the model group. Treatment with Xuefu Zhuyu (XFZY) decoction for 12 weeks significantly reduced the lipid deposition and the number of macrophages (P < 0.05) and significantly increased the collagen content within the plaque (P < 0.01). Enrichment analysis revealed a high enrichment of the Cytokine-cytokine receptor interaction pathway and Chemokine signaling pathway. Noteworthy genes involved in this response included Ccl12, Ccl22, Cx3cr1, Ccr7, Ccr2, Tnfrsf25, and Gdf5. Xuefu Zhuyu decoction significantly downregulated the expression of CX3CL1 and CX3CR1 (P < 0.05) and upregulated the expression of GDF5 (P < 0.01). Compared with control group, in cell models, the mRNA expressions of Ccl12, Ccl22, and Ccr2 were significantly upregulated (P < 0.05 or P < 0.01). Xuefu Zhuyu decoction significantly downregulated the expression of Ccl12, Ccl22, Cx3cr1, Ccr7 and Ccr2 (P < 0.05 or P < 0.01). ConclusionXuefu Zhuyu decoction demonstrates effective regulation of plaque components, retarding plaque progression and preserving plaque stability by modulating lipid metabolism and inflammatory responses. Subsequent transcriptome analysis identified the Cytokine-cytokine receptor interaction and Chemokine signaling pathway as potential key pathways for the therapeutic effects of Xuefu Zhuyu decoction. This insight not only provides crucial avenues for further exploration into the mechanisms underlying Xuefu Zhuyu decoction but also offers valuable perspectives and hypotheses for enhancing disease prevention and treatment strategies.

Lapagyl mitigates UV-induced inflammation and immunosuppression via Foxp3+ Tregs and CCL pathway: A single-cell transcriptomics study

BackgroundAs the largest organ of the body, the skin is constantly subjected to ultraviolet radiation (UVR), leading to inflammations and changes that mirror those seen in chronological aging. Although various small molecule drugs have been explored for treating skin photoaging, they typically suffer from low stability and a high incidence of adverse reactions. Consequently, the continued investigation of photoaging treatments, particularly those utilizing herbal products, remains a critical clinical endeavor. One such herbal product, Lapagyl, is derived from the bark of the lapacho tree and possesses antioxidant efficacies that could be beneficial in combating skin photoaging. PurposeThis research aimed to evaluate the efficacy of the herbal product Lapagyl in combating UVR-induced skin photoaging. Additionally, it sought to unravel the mechanisms by which Lapagyl promotes the regeneration of the skin extracellular matrix. MethodsTo investigate whether Lapagyl can alleviate skin aging and damage, a UVR radiation model was established using SKH-1 hairless mice. The dorsal skins of these mice were evaluated for wrinkle formation, texture, moisture, transepidermal water loss (TEWL), and elasticity. Pathological assessments were conducted to determine Lapagyl's efficacy. Additionally, single-cell sequencing and spectrum analysis were employed to elucidate the working mechanisms and primary components of Lapagyl in addressing UVR-induced skin aging and injury. ResultsLapagyl markedly reduced UVR-induced wrinkles, moisture loss, and elasticity decrease in SKH-1 mice. Single-cell sequencing demonstrated that Lapagyl corrected the imbalance in cell proportions caused by UVR, decreased UVR-induced ROS expression, and protected basal and spinous cells from skin damage. Additionally, Lapagyl effectively prevented the entry of inflammatory cells into the skin by reducing CCL8 expression and curtailed the UVR-induced formation of Foxp3+ regulatory T cells (Tregs) in the skin. Both pathological assessments and ex vivo skin model results demonstrated that Lapagyl effectively reduced UVR-induced damage to collagen and elastin. Spectrum analysis identified Salidroside as the primary compound remaining in the skin following Lapagyl treatment. Taken together, our study elucidated the skin protection mechanism of the herbal product Lapagyl against UVR damage at the cellular level, revealing its immunomodulatory effects, with salidroside identified as the primary active compound for skin. ConclusionOur study provided a thorough evaluation of Lapagyl's protective effects on skin against UVR damage, delving into the mechanisms at the cellular level. We discovered that Lapagyl mitigates skin inflammation and immunosuppression by regulating Foxp3+ Tregs and the CCL pathway. These insights indicate that Lapagyl has potential as a novel therapeutic option for addressing skin photoaging.

Active fractions from Jingfang Baidu Powder alleviate Klebsiella-induced Pneumonia by inhibiting TLR4/Myd88-ERK signaling pathway

Ethnopharmacological relevanceJingfang Baidu Powder (JFBDP) is a classic traditional Chinese medicine prescription. Although Jingfang Baidu powder obtained a general consensus on clinical efficacy in treating pneumonia, there were many Chinese herbal drugs in formula, complex components, and large oral dosage, which brings certain obstacles to clinical application. Aim of the studyTherefore, screening of the active fraction that exerts anti-pneumonia helps improve the pharmaceutical preparation, improve the treatment compliance of patients, and further contribute to the clinical application, and the screening of the new active ingredients with anti-pneumonia. The histopathological observation, real-time quantitative PCR, western blotting, and immunofluorescence were applied to evaluate the anti-pneumonia efficacy of active fractions from JFBDP. ResultsThree fractions from JFBDP inhibit the gene expression of IL-1β, IL-10, CCL3, CCL5, and CCL22 in lung tissue infected by Klebsiella at various degrees, and presented a good dose-response relationship. JF50 showed stronger anti-inflammatory effects among three fractions including JF30, JF50, and JF75. Besides, JF50 significantly reduced the protein expression of TLR4 and Myd88 in lung tissue infected with Klebsiella, and it also significantly inhibited p-ERK and p–NF–κB p65. JF50 significantly inhibits the protein expression of Caspase 3, Caspase 8, and Caspase 9 in lung tissue infected with Klebsiella at the dose of 25 mg/kg and 50 mg/kg. ConclusionJF50 improves lung pathological damage in Klebsiella pneumonia mice by inhibiting the TLR4/Myd88/NF-κB-ERK signaling pathway, and inhibiting apoptosis of lung tissue cells. These findings provide a reference for further exploring the active substance basis of Jingfang Baidu Powder in treating bacterial pneumonia.

Abstract LB263: A first-in-class multimodal immunotherapy for induction of tertiary lymphoid structures as a novel therapeutic strategy for solid tumors

Abstract Immune checkpoint inhibitors (ICI) have transformed cancer treatment. However, long term disease control is often not achieved and resistance frequently occurs. Formation of organized intratumoral aggregates of lymphocytes (tertiary lymphoid structures, TLS) has been associated with response to ICI suggesting therapeutics able to induce intratumoral TLS could enhance the response to ICI treatment. TLS formation requires antigen presentation, stromal activation and immune stimulation - diverse events difficult to obtain with a single therapeutic. The enLIGHTEN™ Discovery Platform aims to create multimodal therapeutics by leveraging human biology and advanced analytics to select multigene payloads delivered by herpes simplex virus (HSV) vectors to the tumor microenvironment. Optimal payload combinations are predicted based on in silico experiments and then tested in proprietary multiplex assays used to evaluate the contribution of payload components and model the therapeutic biological effect of predicted payload combinations. Alpha-201, a replication-defective oncolytic virus, was selected from a suite of modified HSV vectors as the biological chassis due to its ability to release tumor antigens and activate pathways associated with response to ICI (e.g., MYC targets, E2F targets, G2M checkpoint; normalized enrichment scores of 2.4, 3.0, and 3.2, respectively, p&amp;lt;0.001). A library of single gene encoding Alpha-201 vectors was constructed, each expressing one in silico predicted payload component (e.g., IL-7, CXCL13, LTB or CCL19). The top two scoring combinations of these viral gene constructs (termed Multiplex A and Multiplex B) were next tested for their effects on TLS induction and anti-tumor efficacy in complementary in vivo models. First, the ability of HSV gene construct combinations to induce TLS was tested in murine salivary glands, a tissue highly permissive to TLS formation. As predicted, delivery of both multiplexes increased the number, size, organization and maturity of virally induced TLS. Of note, TLS were characterized by the presence of mature fibroblastic reticular cells and CCL21 expression, effects not observed with biological chassis administration alone. Second, anti-tumor efficacy was tested in EMT6 tumor-bearing mice. Both multiplexes induced tumor growth inhibition compared to vehicle control mice (Multiplex A: 39.8±10.5%, p=0.004, Multiplex B: 38.6%±12.1, p=0.011, n=8 per group). In combination with anti-PD-1 antibody therapy, multiplex treatment also increased the number of long-term survivors (&amp;gt;40 days) as compared to control (2/11 vs. 0/8). Characterization of intratumoral TLS induction is ongoing. In conclusion, we have demonstrated the ability of enLIGHTEN™ to design multimodal specific therapeutics, resulting in the development of a first-in-class immunotherapeutic for TLS induction in solid tumors. Citation Format: Anne R. Diers, Qiuchen Guo, John D. Christie, David Krisky, Fabrina M. Gaspal, Erin Richardson, Charlotte G. Smith, David R. Withers, Adam P. Croft, Paul P. Tak, Francesca Barone. A first-in-class multimodal immunotherapy for induction of tertiary lymphoid structures as a novel therapeutic strategy for solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB263.

Gut Microbiome and Transcriptomic Changes in Cigarette Smoke-Exposed Mice Compared to COPD and CD Patient Datasets.

Chronic obstructive pulmonary disease (COPD) patients and smokers have a higher incidence of intestinal disorders. The aim of this study was to gain insight into the transcriptomic changes in the lungs and intestines, and the fecal microbial composition after cigarette smoke exposure. Mice were exposed to cigarette smoke and their lung and ileum tissues were analyzed by RNA sequencing. The top 15 differentially expressed genes were investigated in publicly available gene expression datasets of COPD and Crohn's disease (CD) patients. The murine microbiota composition was determined by 16S rRNA sequencing. Increased expression of MMP12, GPNMB, CTSK, CD68, SPP1, CCL22, and ITGAX was found in the lungs of cigarette smoke-exposed mice and COPD patients. Changes in the intestinal expression of CD79B, PAX5, and FCRLA were observed in the ileum of cigarette smoke-exposed mice and CD patients. Furthermore, inflammatory cytokine profiles and adhesion molecules in both the lungs and intestines of cigarette smoke-exposed mice were profoundly changed. An altered intestinal microbiota composition and a reduction in bacterial diversity was observed in cigarette smoke-exposed mice. Altered gene expression in the murine lung was detected after cigarette smoke exposure, which might simulate COPD-like alterations. The transcriptomic changes in the intestine of cigarette smoke-exposed mice had some similarities with those of CD patients and were associated with changes in the intestinal microbiome. Future research could benefit from investigating the specific mechanisms underlying the observed gene expression changes due to cigarette smoke exposure, focusing on identifying potential therapeutic targets for COPD and CD.

Aflatoxin B1 and Epstein–Barr virus-induced CCL22 expression stimulates B cell infection

Epstein-Barr Virus (EBV) infects more than 90% of the adult population worldwide. EBV infection is associated with Burkitt lymphoma (BL) though alone is not sufficient to induce carcinogenesis implying the involvement of co-factors. BL is endemic in African regions faced with mycotoxins exposure. Exposure to mycotoxins and oncogenic viruses has been shown to increase cancer risks partly through the deregulation of the immune response. A recent transcriptome profiling of B cells exposed to aflatoxin B1 (AFB1) revealed an upregulation of the Chemokine ligand 22 (CCL22) expression although the underlying mechanisms were not investigated. Here, we tested whether mycotoxins and EBV exposure may together contribute to endemic BL (eBL) carcinogenesis via immunomodulatory mechanisms involving CCL22. Our results revealed that B cells exposure to AFB1 and EBV synergistically stimulated CCL22 secretion via the activation of Nuclear Factor-kappa B pathway. By expressing EBV latent genes in B cells, we revealed that elevated levels of CCL22 result not only from the expression of the latent membrane protein LMP1 as previously reported but also from the expression of other viral latent genes. Importantly, CCL22 overexpression resulting from AFB1-exposure in vitro increased EBV infection through the activation of phosphoinositide-3-kinase pathway. Moreover, inhibiting CCL22 in vitro and in humanized mice in vivo limited EBV infection and decreased viral genes expression, supporting the notion that CCL22 overexpression plays an important role in B cell infection. These findings unravel new mechanisms that may underpin eBL development and identify novel pathways that can be targeted in drug development.

Single-cell RNA sequencing reveals recruitment of the M2-like CCL8high macrophages in Lewis lung carcinoma-bearing mice following hypofractionated radiotherapy

BackgroundTumor-associated macrophages (TAMs) play a pivotal role in reshaping the tumor microenvironment following radiotherapy. The mechanisms underlying this reprogramming process remain to be elucidated.MethodsSubcutaneous Lewis lung carcinoma (LLC) murine model was treated with hypofrationated radiotherapy (8 Gy × 3F). Single-cell RNA sequencing was utilized to identify subclusters and functions of TAMs. Multiplex assay and enzyme-linked immunosorbent assay (ELISA) were employed to measure serum chemokine levels. Bindarit was used to inhibit CCL8, CCL7, and CCL2. The infiltration of TAMs after combination treatment with hypofractionated radiotherapy and Bindarit was quantified with flow cytometry, while the influx of CD206 and CCL8 was assessed by immunostaining.ResultsTranscriptome analysis identified a distinct subset of M2-like macrophages characterized by elevated Ccl8 expression level following hypofractionated radiotherapy in LLC-bearing mice. Remarkbly, hypofractionated radiotherapy not only promoted CCL8high macrophages infiltration but also reprogrammed them by upregulating immunosuppressive genes, thereby fostering an immunosuppressive tumor microenvironment. Additioinally, hypofractionated radiotherapy enhanced the CCL signaling pathway, augmenting the pro-tumorigenic functions of CCL8high macrophages and boosting TAMs recruitment. The adjunctive treatment combining hypofractionated radiotherapy with Bindarit effectively reduced M2 macrophages infiltration and prolonged the duration of local tumor control.ConclusionsHypofractionated radiotherapy enhances the infiltration of CCL8high macrophages and amplifies their roles in macrophage recruitment through the CCL signaling pathway, leading to an immunosuppressive tumor microenvironment. These findings highlight the potential of targeting TAMs and introduces a novel combination to improve the efficacy of hypofractionated radiotherapy.

Prior Exposure to Experimental Preeclampsia Increases Atherosclerotic Plaque Inflammation in Atherogenic Mice-Brief Report.

Women with a history of preeclampsia have evidence of premature atherosclerosis and increased risk of myocardial infarction and stroke compared with women who had a normotensive pregnancy. Whether this is due to common risk factors or a direct impact of prior preeclampsia exposure has never been tested in a mouse atherosclerosis model. Pregnant LDLR-KO (low-density lipoprotein receptor knockout; n=35) female mice were randomized in midgestation to sFlt1 (soluble fms-like tyrosine kinase 1)-expressing adenovirus or identical control adenovirus. Postpartum, mice were fed high-fat diet for 8 weeks to induce atherogenesis. Comparison between the control and preeclampsia models was made for metabolic parameters, atherosclerosis burden and composition by histology, plaque inflammation by flow cytometry, and aortic cytokines and inflammatory markers using a cytokine array. In pregnant LDLR-KO mice, sFlt1 adenovirus significantly induced serum sFlt1, blood pressure, renal endotheliosis, and decreased pup viability. After 8 weeks of postpartum high fat feeding, body weight, fasting glucose, plasma cholesterol, HDL (high-density lipoprotein), and LDL (low-density lipoprotein) were not significantly different between groups with no change in aortic root plaque size, lipid content, or necrotic core area. Flow cytometry demonstrated significantly increased CD45+ aortic arch leukocytes and CD3+T cells and aortic lysate contained more CCL (CC motif chemokine ligand) 22 and fetuin A and decreased expression of IGFBP6 (insulin-like growth factor-binding protein 6) and CCL21 in preeclampsia-exposed mice compared with controls. In atherogenic LDLR-KO mice, exposure to sFlt1-induced preeclampsia during pregnancy increases future atherosclerotic plaque inflammation, supporting the concept that preeclampsia directly exacerbates atherosclerotic inflammation independent of preexisting risk factors. This mechanism may contribute to ischemic vascular disease in women after preeclampsia pregnancy.