Expression Of CD86 Research Articles

Th22 cells promote the transition from homeostatic to reactive microglia in diabetic encephalopathy.

Diabetic encephalopathy (DE) is one of the most serious complications of diabetes mellitus (DM), and its pathogenesis has not yet been clarified. Th22 cells are a newly discovered class of CD4+ T cells that play important roles in inflammatory, autoimmune and infectious diseases. However, it is unclear whether Th22 cells are involved in the pathogenesis of DE. We established a T2DM mouse model in vivo and cocultured Th22 cells with microglia under high glucose (HG) conditions in vitro. Cognitive dysfunction was evaluated using the Morris water maze (MWM) test; blood‒brain barrier (BBB) integrity was evaluated using the Evans blue (EB) extravasation assay; Th22 cells and IL-22 receptors were detected by immunofluorescence; and IL-1β, TNF-α, iNOS, CD86, Arg-1, and CD206 protein expression was measured by Western Blot (WB) analysis. Th22 cells passed through the BBB into the hippocampus and secreted interleukin-22 (IL-22), and the mice subsequently exhibited decreased learning and memory abilities. In the DE model, IL-22 promoted the transformation of homeostatic microglia into reactive microglia as well as the inflammatory response. Additionally, coculture of Th22 cells with BV2 microglia cultured under HG conditions increased the production of proinflammatory cytokines, and the microglia showed reactive changes. Mechanistically, IL-22Rα1 acted as a ligand, and IL-22 bound to IL-22Rα1 on microglia to drive primary microglia-induced inflammatory responses. Interestingly, interleukin-22 binding protein (IL-22BP) directly binds to IL-22Rα1 on microglia to inhibit the proinflammatory effects of IL-22. Th22 cells secrete IL-22 after passing through the BBB into the hippocampus and promote the transformation of homeostatic microglia into reactive microglia, which induces an inflammatory response, exacerbates learning and memory impairment and cognitive deficits, and contributes to and accelerates the development of DE.

Homocysteine affects macrophage polarization by altering m6A methylation of scavenger receptors CD209 and CD163L1

ABSTRACT Atherosclerosis is a chronic inflammatory disease characterized by fatty plaque deposits on artery walls. Elevated plasma homocysteine (Hcy) levels are an independent risk factor for atherosclerosis. Research on the mechanism by which Hcy promotes atherosclerosis has gradually turned to epigenetic inheritance, but the correlation between Hcy and m6A (N6-methyladenosine) modification has not been reported. In this study, MeRIP-seq was performed on macrophages and Hcy-treated macrophages. GO and KEGG analyses were used to perform functional analysis of differentially methylated genes. qRT-PCR and western blot were taken to determine the expression of CD209, CD163L1, proinflammatory, and anti-inflammatory factors. Flow cytometry was used to detect the proportion of M2 macrophages. The results showed that after Hcy treatment, the overall m6A methylation of macrophages was down-regulated, and 856 differential methylation peaks were annotated to 781 genes. These included CD209 and CD163L1, whose m6A methylation was inhibited after treatment with Hcy. In addition, mRNA and protein expressions of CD209 and CD163L1 were also inhibited after Hcy treatment. Overexpression of CD209 or CD163L1 prevents the Hcy-induced decrease in the proportion of M2 macrophages. This article identified changes in the modification level of m6A in macrophages by Hcy and revealed the possible mechanism by which Hcy induces macrophage polarization.

Human Umbilical Cord Mesenchymal Stem Cell-Derived Exosomes Loaded Mir-29-3p Targets AhR to Improve Juvenile Idiopathic Arthritis via Inhibiting the Expression of IL-22 in CD4+ T Cell.

Juvenile idiopathic arthritis (JIA) is one of the most common chronic inflammatory rheumatic diseases in children. Human umbilical cord mesenchymal stem cells (HUCMSCs)-derived exosomes (HUCMSCs-Exos) are involved in autoimmune diseases. This study investigates the mechanism of HUCMSC-Exos in improving JIA by targeting AhR through delivery of miR-29-3p to inhibit IL-22 expression in CD4+ T cells. Collagen induced arthritis (CIA) mouse model was established, and mice were treated with HUCMSCs-Exos and miR-29-3p antagomir, respectively. CD4+ T cells from JIA patients were used for cell experiments. The mechanism was elucidated by histopathological staining, transmission electron microscopy (TEM), immunohistochemistry, CCK-8 assay, flow cytometry, Western blotting, real-time PCR, and enzyme-linked immunosorbent assay (ELISA), laser confocal microscopy, and luciferase assay. JIA-CD4+ T cells showed higher expression of IL-22 and lower the levels of miR-29-3p, while HUCMSCs-Exos significantly inhibited the expression of IL-22 and increased the levels of miR-29a-3p, miR-29b-3p, and miR-29c-3p in CD4+ T cells from JIA patients. The expression of miR-29a-3p, miR-29b-3p, miR-29c-3p, AhR, and IL-22 in CD4+ T cells was significantly reversed when co-cultured with HUCMSCs transfected with miR-29-3p mimic or miR-29-3p inhibitor. In vivo experiment, HUCMSCs-Exos ameliorated CIA mice by delivering miR-29-3p to inhibit AhR, IL-22, IL-22R1, MMP3, and MMP13 expression. Furthermore, HUCMSCs-Exos also deliver miR-29-3p targeting AhR expression to inhibit IL-22 in JIA-CD4 + T cells through alleviating arthritic synovial fibroblast activation. HUCMSCs-Exos loaded miR-29-3p targets AhR to improve JIA via inhibiting the expression of IL-22 in CD4+ T cell, which provides a scientific basis for the treatment of JIA.

Cholesterol promotes IFNG mRNA expression in CD4+ effector/memory cells by SGK1 activation.

IFNγ-secreting T cells are central for the maintenance of immune surveillance within the central nervous system (CNS). It was previously reported in healthy donors that the T-cell environment in the CNS induces distinct signatures related to cytotoxic capacity, CNS trafficking, tissue adaptation, and lipid homeostasis. These findings suggested that the CNS milieu consisting predominantly of lipids mediated the metabolic conditions leading to IFNγ-secreting brain CD4 T cells. Here, we demonstrate that the supplementation of CD4+CD45RO+CXCR3+ cells with cholesterol modulates their function and increases IFNG expression. The heightened IFNG expression was mediated by the activation of the serum/glucocorticoid-regulated kinase (SGK1). Inhibition of SGK1 by a specific enzymatic inhibitor significantly reduces the expression of IFNG Our results confirm the crucial role of lipids in maintaining T-cell homeostasis and demonstrate a putative role of environmental factors to induce effector responses in CD4+ effector/memory cells. These findings offer potential avenues for further research targeting lipid pathways to modulate inflammatory conditions.

Autoreactive B cells remain active despite clinical disease control in rheumatoid arthritis

BackgroundAutoimmune diseases (AIDs) are frequently hallmarked by the presence of autoreactive B cell responses which are involved in disease pathogenesis. However, the dynamics of such responses and their relation to clinical disease activity in humans is poorly understood. Rheumatoid arthritis (RA), a prototypic chronic AID, is hallmarked by B cell responses directed against citrullinated proteins. ObjectiveTo determine the relation between the activity of the anti-citrullinated protein antibody (ACPA) B cell response and clinical disease activity in ACPA+ patients with RA. MethodsExpression of B cell activation markers by ACPA+, tetanus toxoid (TT)+ and ACPA− memory B cells (MBCs) from peripheral blood of ACPA+ RA patients receiving different treatments was analyzed by flow cytometry. Results were correlated to clinical disease activity. ResultsCompared to TT+ and ACPA− MBCs, ACPA+ MBCs displayed a highly activated phenotype as evidenced by increased expression of Ki-67, CD86, CD80, CD19 and CD20 and reduced expression of CD32. The activated phenotype of ACPA+ MBCs did not associate with clinical disease activity in a cross-sectional analysis of RA patients treated with various therapeutic agents. Also, in a longitudinal analysis of patients treated with Janus kinase (JAK) inhibitors, ACPA+ MBCs retained their activated phenotype despite effective control of inflammation and clinical disease. ConclusionACPA+ MBCs remain active despite clinical disease control in patients with RA across a range of interventions. This persistent activity indicates the absence of immunological remission and might explain why ACPA+ patients rarely reach sustained drug-free remission and frequently flare upon drug tapering.

Licochalcone A loaded multifunctional chitosan hyaluronic acid hydrogel with antibacterial and inflammatory regulating effects to promote wound healing

The wound healing process is characterized by persistent infection and long-term inflammation. The licochalcone A (LicA) has the potential for skin wound healing and needs a good drug-loading platform to apply its antibacterial and anti-inflammatory effects. In this study, the LicA@chitosan (CS) -hyaluronic acid (HA) hydrogel with antibacterial and anti-inflammatory was developed for wound healing in mice. The SEM displayed that the hydrogel had an obvious porous structure and was very suitable to be used as a delivery carrier for LicA. The FTIR results suggested that the LicA can be effectively loaded in the CS-HA hydrogel. Variable strain scanning, frequency scanning and temperature scanning indicated that the LicA@CS-HA hydrogel can maintain the gel state. The LicA@CS-HA hydrogel had good biological safety, can inhibit the activity of Escherichia coli and Staphylococcus aureus, and can release LicA stably. The LicA@CS-HA hydrogel also has good adhesion and hemostatic properties. Finally, the LicA@CS-HA hydrogel significantly accelerated wound healing in mice skin injury model, and reduced inflammation and orderly collagen deposition were observed by HE and Masson staining. The immunohistochemistry indicated that the LicA@CS-HA hydrogel induced the positive expression of CD31, VEGF, and HIF-1α promoted neovascularization. The LicA@CS-HA hydrogel also down-regulated the expression of M1 macrophage markers CD86, IL-6, and TNF-α, and increased the expression of M2 macrophage markers CD206, IL-4, and IL-10 proteins. The molecular docking demonstrated that the target proteins had better binding activity to LicA. Collectively, the LicA@CS-HA hydrogel has broad application prospects in promoting wound healing.

Bicalutamide Reveals Immunomodulatory Effects in Prostate Cancer by Regulating Immunogenic Dendritic Cell Maturation

Prostate cancer poses a significant global health challenge, ranking as the second most prevalent and fifth most lethal malignancy among males. The intricate interplay between androgen signaling and the immune microenvironment underscores the complexity of prostate cancer progression. Notably, androgen receptor (AR) signaling has been shown to affect immune response mediated by tumor antigen-presenting dendritic cells (DCs). Therefore, this study aimed to explore the potential of Bicalutamide, a nonsteroidal anti-androgen, in modulating DCs-mediated immune responses. Peripheral blood mononuclear cells (PBMCs) were isolated, and monocytes were extracted, followed by their differentiation into immature dendritic cells (iDCs) using GM-CSF and IL-4. Harvested tumor cell lysates from human prostate cancer cells were then utilized to induce the transformation of iDCs into mature dendritic cells (mDCs). Then, mDCs were treated with non-toxic concentration of Bicalutamide determined by annexin V/PI assay. The morphological characteristics of mDCs were investigated using an inverted light microscope. Flow cytometry was used to determine the cell surface expression of molecular markers of DC maturation, and qRT-PCR was employed to evaluate expression levels of proinflammatory genes involved in DC maturation. The obtained results indicated that Bicalutamide treatment of monocyte-derived mDCs induces an immunogenic and matured phenotype, marked by increased expression of CD86 and HLA-DR. Besides, qRT-PCR results evidenced that Bicalutamide decreased the expression of anti-inflammatory genes, including Interleukin-10 (IL-10) and TGF-beta, as an indication of immunogenic DCs. These findings suggest that beyond its established anti-androgen role, Bicalutamide may exert anti-tumor effects through the modulation of DCs-mediated immune responses. This novel immunomodulatory feature holds promise for the development of novel therapies, including combination therapies, in prostate cancer treatment.

Adjuvant rituximab and elevated intratumoural CD8 expression are associated with sustained disease control after radiotherapy in a randomised trial of systemic therapy in early-stage follicular lymphoma

We report extended follow-up of TROG99.03, a randomised phase III trial in early-stage follicular lymphoma (ESFL) including new information on the role of adjuvant rituximab and translational studies. Patients with ESFL were randomised to involved field radiotherapy (IFRT) or IFRT plus 6-cycles cyclophosphamide/vincristine/prednisolone (IFRT+CVP). From 2006 rituximab was added to IFRT+CVP (IFRT+R-CVP). Clinical and multi-omic parameters were evaluated. Findings were validated in two independent ESFL cohorts (99 and 60 patients respectively). Between 2000 and 2012, 150 (75 per arm) patients were recruited. 48% were positron emission tomography (PET)-staged. By protocol, at median follow-up 11.3-years, progression-free survival (PFS) remained superior for IFRT+(R)CVP vs. IFRT (hazard ratio [HR]=0.60, 95% CI=0.37-0.98, p=0.043; 10-year PFS 62% vs. 43%) respectively. Although no significant difference in overall survival was observed (HR=0.44, 95% CI=0.16-1.18, p=0.11, 10-year OS 95% vs. 84%), patients receiving IFRT+(R)CVP experienced fewer composite (histological transformation and death) events (p=0.045). PFS of IFRT+R-CVP-treated patients compared with all other treatments lacking rituximab (IFRT alone plus IFRT+CVP) was superior (HR=0.36, 95% CI=0.13-0.82, p=0.013). Amongst PET-staged patients, PFS differences between IFRT+R-CVP vs. IFRT were maintained (HR=0.38, 95% CI=0.16-0.89, p=0.027) indicating benefit distinct from stage migration. FL-related mutations and BCL2-translocations were not associated with PFS. However, by multivariate analysis elevated CD8A gene expression in diagnostic biopsy tissue was independently associated with improved PFS (HR=0.45, 95% CI=0.26-0.79, p=0.037), a finding confirmed in both ESFL validation cohorts. CD8A gene expression was raised (p=0.02) and CD8+ T-cell density higher within follicles in ESFL vs. advanced-stage FL (p=0.047). Human leucocyte antigen class I specific neoantigens were detected in 43% of patients, suggesting neoantigen-specific CD8+ T-cells have a role in confining the spread of the disease. Adjuvant R-CVP and elevated intratumoural CD8 expression were independently associated with sustained disease control after radiotherapy in ESFL. Cancer Council Victora; National Health and Medical Research Council; Leukaemia Foundation; Mater Foundation.

Identification of mRNA biomarkers in extremely early hypertensive intracerebral hemorrhage (HICH)

IntroductionHypertensive intracerebral hemorrhage (HICH) stands out as a critical complication of primary hypertension. Consequently, investigating messenger RNA (mRNA) biomarkers becomes imperative, offering potential targets. This study is conducted for elucidating the expression profile of blood mRNA biomarkers in HICH.MethodsTwenty-five HICH patients were constituted the HICH group.Twenty-two healthy volunteers recruited and comprised the control group. Peripheral blood cells were extracted to identify candidate mRNA. The identified differential expressions of genes between the two groups were validated, and the potential associations between these differentially expressed genes and adverse events were analyzed. GO and KEGG enrichment of DEGs, Weighted Gene Co-expression Network and Protein Interaction Network were established. target mRNA was screened.ResultsThe study identified 3163 differentially expressed genes in HICH. 8 candidate mRNA (SPI1, HK3, HCK, SYK, CD14, FCER1G, CYBB, FGR) were pinpointed. Associations with pathways affecting HICH development included HIF-1 signaling, NF-kappa B signaling, and C-type lectin receptor signaling. In the HICH group, higher expressions of HK3, HCK, SYK, CD14, FCER1G, CYBB, and FGR, and lower SPI1 expression compared to the control group. HICH patients experienced high rates of complications: pulmonary infection (84%), epilepsy (16%), enlarged hematoma (20%), gastrointestinal bleeding (48%), malnutrition (84%), and lower limb deep vein thrombosis (DVT) (12%). Factors contributing to pulmonary infection included age and elevated expression of HCK, SYK, CD14, and FGR. SPI1 was associated with epilepsy, while its lower expression correlated with hematoma enlargement. Gastrointestinal bleeding was linked to increased cerebral hemorrhage. Malnutrition was associated with higher age, and expressions of HK3, HCK, SYK, CD14, FCER1G, CYBB, and FGR. Patients with lower limb DVT had elevated expressions of the identified genes.ConclusionIn hypertensive intracerebral hemorrhage, there are elevated expressions of HK3, HCK, SYK, CD14, FCER1G, CYBB, and FGR, along with reduced expression of SPI1. Furthermore, age, along with elevated expressions of HCK, SYK, CD14, and FGR, serves as influencing factors contributing to pulmonary infection in patients.

Influence of Chitosan Purification on the Immunomodulator Potential of Chitosan Nanoparticles on Human Monocytes

The deproteinization of chitosan is a necessary purification process for materials with biomedical purposes; however, chitosan sourcing and purification methods can modify its molecular weight, deacetylation degree, and residual proteins. These factors affect the reactive groups that affect the immunomodulatory activities of cells, particularly macrophages and monocytes; considering this activity is key when developing successful and functional biomaterials. Here, two brands of chitosan were purified and used to synthesize nanoparticles to evaluate their immunomodulatory effect on monocyte and macrophage differentiation. Chitosan FT-IR showed bands related to its purification process, with increased OH group intensity. Nanoparticles (CtsNps) synthesized with purified chitosan were of a smaller size compared to those using unpurified chitosan due to the alkaline purification process’s shortening of the polymeric chain. At low concentrations (50 μg/mL), CtsNps showed a lower expression of CD80 and CD14, corroborating the differentiation effect of chitosan. Inducible nitric oxide synthase (iNOS) is related to a pro-inflammatory response and M1 macrophage polarization was detected in monocytes treated with purified and unpurified nanoparticles. Sigma-purified chitosan nanoparticles (CtsNps SigmaP), at 300 μg/mL, showed arginase production related to an anti-inflammatory response and M2 macrophage polarization. The chitosan purification process induces a shift in the polarization of macrophages to an anti-inflammatory M2 profile. This effect is concentration-dependent and should be further studied in each use case to favor the suitable biological response.

MIF promotes Th17 cell differentiation in rheumatoid arthritis through ATF6 signal pathway

Rheumatoid arthritis (RA) is a common autoimmune disease that can lead to irreversible joint damage when it occurs, but its pathogenesis has not yet been elucidated. In this study, we explored the roles of macrophage migration inhibitory factor (MIF), endoplasmic reticulum stress (ER stress), and Th17 cells in the pathogenesis of RA. We have preliminarily confirmed that MIF expression in CD4+T cells and the proportion of Th17 cells are increased in active RA patients. We also found that ER stress is activated, initiating ATF6 pathway in the UPR. Additionally, using in vitro stimulation and co-immunoprecipitation experiments, we have confirmed the interaction between MIF and ATF6, which enhances protein expression in ATF6 pathway. Subsequently, in the chromatin immunoprecipitation assay, we observed the enrichment of ATF6 subunit on the promoter sequences of the Th17 cell differentiation genes STAT3 and RORC. Additionally, the differentiation of Th17 cells was disrupted by Ceapin-A7 (ATF6 inhibitor). In summary, our results indicate that MIF enhances ATF6 pathway signaling, which promotes the differentiation of Th17 cells. This could be a potential mechanism underlying the pathogenesis of RA, offering a new direction for the clinical treatment of RA.

Differential TLR2 and TLR4 mediated inflammatory and apoptotic responses in asymptomatic and symptomatic Leptospira interrogans infections in canine uterine tissue

Leptospirosis is major zoonotic disease with global implications, affecting both domestic animals and humans. It is caused by Leptospira interrogans (L. interrogans), which can damage multiple organs, including the kidneys, liver, testes, and uterus. Despite this, L. interrogans can also persist asymptomatically in tissues, akin to nonpathogenic strains. The mechanisms driving asymptomatic infections remain poorly understood. This study investigated the role of L. interrogans in asymptomatic infection within the uterine tissue of canines, focusing on the differential expression of Toll-like receptors (TLRs)2 and 4 and their roles in inflammatory and apoptotic pathways. We hypothesized that TLR2 and TLR4 coexpression is crucial for eliciting inflammation and apoptosis, whereas TLR4 alone might be insufficient. Our findings revealed that in symptomatic infections, both TLR2 and TLR4 are coexpressed, leading to markedly elevated levels of the proinflammatory cytokines IL-10, IL-1β, TNF-α, and IL-6. This enhanced inflammatory response is further evidenced by increased CD4 expression, indicating robust T helper cell activation. In contrast, asymptomatic infections are characterized by exclusive TLR4 expression, with inflammatory markers remaining at baseline levels. Additionally, we observed that L. interrogans induces apoptosis in symptomatic animals through TLR2 and TLR4 mediated activation of Caspase 8 and Caspase 3. These findings illustrate that L. interrogans drives both inflammation and apoptosis via the combination of TLR2 and TLR4 actions. When only TLR4 is activated, the immune response is insufficient, resulting in an asymptomatic disease course. This study provides novel insights into the differential roles of TLR receptors in leptospirosis, offering potential directions for targeted therapeutic strategies.

Molecular Insights Into Actinic Cheilitis and Lower Lip Squamous Cell Carcinoma: AURKA and AURKB Amplifications and Their Association With Tumor Microenvironment.

Lip exposure to carcinogens lead to several disorders, such as actinic cheilitis (AC) and lower lip squamous cell carcinoma (LLSCC). Although several studies have described important pathways in lip carcinogenesis, the comprehension of association of target genes in this process and their association with tumor microenvironment still need to be better understood. Tissue samples of 30 AC and 17 LLSCC cases were included for histopathological analysis, immunohistochemical expression of CD4, CD8, and PD-L1, and fluorescence insitu hybridization for AURKA, AURKB, TP53, PTEN, CCND1, and MYC. Non-parametrical tests were done and p < 0.05 was considered significant. LLSCC patients presented higher amplifications of AURKA and AURKB, deletion of TP53, and PTEN and rearrangements of MYC than AC. AURKA, AURKB, TP53, PTEN, and CCND1 changes were correlated with PD-L1 expression. AURKA and AURKB amplifications and other gene changes are pointed by their association of lip disorders.

Tumor expression of CD83 reduces glioma progression and is associated with reduced immunosuppression.

Malignant glioma, the most lethal form of brain cancer, presents with an immunosuppressive microenvironment that obstructs tumor cell clearance and hampers immunotherapeutic interventions. Despite advancements in characterizing cellular and extracellular profiles in cancer, the immunosuppressive mechanisms specific to glioma remain poorly understood. We conducted single-cell RNA sequencing of glioma samples, which revealed a select subset of human and mouse glioma cells that express CD83, a marker associated with mature antigen-presenting cells (APCs). To investigate the impact of tumor cell CD83 expression of glioma outcomes, we employed an immunocompetent mouse model of glioma, bioinformatics analyses of human samples and in vitro assays. Our findings revealed that CD83+ tumor cells contribute to tumor growth suppression and are associated with enhanced cytotoxic T cell profiles and activated CD8+ T cells. Increased proinflammatory cytokines were identified in CD83-overexpressing tumor conditions, which were also correlated with long-term CD8+ antitumor responses. Importantly, tumor-derived CD83 could mediate communication with T cells, altering the immune microenvironment to potentially enhance immune related tumor clearance. Collectively, our data suggest that tumor cell expression of CD83 supports the endogenous anti-tumor T cell constituency in malignant glioma. Future research endeavors may aim to further investigate whether CD83 expression can enhance immunotherapeutic approaches and improve patient outcomes.

Paraoxonase-1 Is a Pivotal Regulator Responsible for Suppressing Allergic Airway Inflammation Through Adipose Stem Cell-Derived Extracellular Vesicles

Although adipose stem cell (ASC)-derived extracellular vesicles (EVs) are as effective as ASCs in the suppression of Th2 cell-mediated eosinophilic inflammation, the role of identified pulmonary genes has not been well documented. Thus, we assessed the immunomodulatory effects of paraoxonase-1 (PON1) on allergic airway inflammation in a mouse model of asthma. Five-week-old female C57BL/6 mice were sensitized to ovalbumin (OVA) by intraperitoneal injection and challenged intranasally with OVA. To evaluate the effect of PON1 on allergic airway inflammation, the intranasal and intraperitoneal injections of recombinant mouse serum PON1 (5 μg/50 μL) were performed before the OVA challenge. We evaluated airway hyperresponsiveness (AHR), total inflammatory cells, and eosinophils in the bronchoalveolar lavage fluid (BALF), lung histology, serum immunoglobulin (Ig), cytokine profiles of BALF and lung draining lymph nodes (LLNs), the expression of interleukin (IL)-25 and transforming growth factor (TGF)-β in mouse lung epithelial cell (MLE-12 cell), and dendritic cell (DC) differentiation. The intraperitoneal and intranasal administration of PON1 significantly decreased AHR, total inflammatory cells and eosinophils in BALF, eosinophilic airway inflammation, serum total, and OVA-specific IgE. PON1 treatment, which marked reduced IL-4, IL-5, and IL-13 in the BALF and LLN but significantly increased interferon-γ and TGF-β. Furthermore, PON1 treatment significantly decreased the expression of IL-25 and increased TGF-β in MLE-12 cells. The expressions of CD40, CD80, and CD86 in immature DCs were significantly increased by PON1 treatment. The administration of PON1 ameliorated allergic airway inflammation and improved AHR through the downregulation of IL-4, IL-5, and IL-13 and upregulation of TGF-β in asthmatic mice. Furthermore, PON1 treatment decreased Th2-mediated inflammation induced by Aspergillus protease antigen by decreasing IL-25 and increasing TGF-β.

Immuno-oncologic profiling by stage-dependent transcriptome and proteome analyses of spontaneously regressing canine cutaneous histiocytoma.

Canine cutaneous histiocytoma (CCH) is a tumor that originates from dermal Langerhans cells and affects particularly young dogs. The common spontaneous regression of CCH makes it an interesting model in comparative oncology research. Previous studies have indicated that anti-tumor immune responses may be involved, but details remain speculative to date. Here, we asked which specific immuno-oncological dynamics underlie spontaneous regression of CCH on mRNA and protein levels. QuantSeq 3' mRNA sequencing with functional over-representation analysis and an nCounter RNA hybridization assay were employed on 21 formalin-fixed, paraffin-embedded CCH samples representing three different tumor stages (dataset information: GSE261387-Immuno-Oncologic Profiling by Stage-Dependent Transcriptome and Proteome Analyses of Spontaneously Regressing Canine Cutaneous Histiocytoma-OmicsDI). Nine additional samples were subjected to matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). Surprisingly, only minor stage-specific differences were found. When we investigated expression of B7 family ligands and CD28 family receptors holding co-stimulatory and -inhibitory functions, respectively, we found a higher abundance of CD80, CD86, CTLA4 and CD28, which may trigger a balanced activation of lymphocyte-mediated immune responses. CD80 and CD86 expressing cells were further quantified by in situ hybridization and compared with data from three cases of canine histiocytic sarcoma (HS), a malignant tumor variant originating from antigen-presenting interstitial dendritic cells. A stage-specific increase of CD80 expressing cells was recorded in CCH from the tumor bottom to the top, while CD86 was continuously and homogenously expressed at high levels. Overall expression of CD80 in CCH was similar to that in HS (73.3 ± 37.4% vs 62.1 ± 46.4%), while significantly more CD86 expressing tumor cells were found in CCH (94.7 ± 10.3%) when compared to HS (57.6 ± 11.0%). Our data suggest that major immuno-oncological pathways are not regulated during regression of CCH on the mRNA or protein levels as detectable by the methods used. Instead, our data provide further evidence supporting previous hypotheses towards a role of immune stimulatory B7 family ligands and CD28 family receptors in the regression of CCH.

Harnessing Regulatory T Cells for Immune Modulation in Transplantation Tolerance

Regulatory T cells (Tregs) are pivotal in maintaining immune tolerance and preventing allograft rejection in transplantation. This review explores the mechanisms by which Tregs mediate immune modulation and their potential therapeutic applications in promoting transplantation tolerance. Tregs are characterized by the expression of CD4, CD25, and the transcription factor FOXP3, and they play a critical role in suppressing effector T cell responses and promoting an anti-inflammatory environment. Various strategies for harnessing Tregs for transplantation include the expansion of Tregs ex vivo, the induction of Tregs in vivo through various approaches, and the transfer of Tregs into transplant recipients. Furthermore, we discuss the impact of the transplant environment on Treg function, the role of dendritic cells and cytokines in Treg activation, and the significance of gut-derived Tregs in fostering tolerance. Additionally, we address the challenges of using Tregs in clinical settings, including potential risks such as opportunistic infections and malignancies. Ultimately, harnessing Tregs represents a promising avenue for achieving transplantation tolerance and improving long-term graft survival, and ongoing research is crucial for developing effective and safe strategies for clinical application. Keywords: Regulatory T cells, Transplantation tolerance, Immune modulation, Allograft rejection, Treg therapy

Metformin alleviates colitis-associated colorectal cancer via inhibition of the TLR4/MyD88/NFκB/MAPK pathway and macrophage M2 polarization

BackgroundColon inflammation plays an essential role in the development and progression of colorectal cancer. Emerging evidence from clinical and animal studies indicates that metformin may reduce the risk of colorectal cancer through its anti-inflammatory effects. AimsTo investigate the efficacy of metformin in reducing the risk of colorectal cancer and the possible pathways and mechanisms. MethodsThe Enterotoxigenic Bacteroides Fragilis (ETBF)/azoxymethane (AOM)/dextran sulfate sodium (DSS) mouse model was established and low-dose metformin (125 mg/kg) or high-dose metformin (250 mg/kg) was administered daily by gavage. Colon tumors were counted, and colon tissue was stained with hematoxylin and eosin (HE) and Periodic Acid-Schiff’s and Alcian Blue (PAS-AB). Colon Ki67, ZO-1 Muc2, Claudin-1, Occludin, MPO, reactive oxygen species (ROS), E-cadherin, CD206 and Arg-1 expression were detected by immunohistochemistry or immunofluorescence staining. NF-κB pathway-related protein expression was assessed by Western blot. Fecal short-chain fatty acid (SCFA) levels were also examined. ResultsOur results showed that low- or high-dose metformin ameliorates colonic mucosal damage, reduces colonic inflammation, and eventually inhibits colorectal tumorigenesis in the ETBF/AOM/DSS mouse model. Our further research found that metformin suppresses the expression of TLR4/MyD88/NFκB/MAPK pathway-related proteins, modulates macrophage M2 polarization and increases SCFA levels in colon contents, which may be the mechanisms by which metformin exerts a protective effect against colon carcinogenesis. ConclusionMetformin inhibited colorectal tumorigenesis by suppressing the TLR4/MyD88/NFκB/MAPK pathway, modulating macrophage M2 polarization and increasing SCFA levels. It holds promise as a potentially effective treatment for colorectal cancer.

The clinical significance of signal regulatory protein alpha expression in the immune environment of gastric cancer.

Signal regulatory protein alpha (SIRPα) inhibits phagocytosis by macrophages by interacting with CD47. Despite its known role in various cancers, the clinical significance of SIRPα in gastric cancer (GC) remains unclear. This study aimed to elucidate the clinical implications of SIRPα in GC, exploring its relevance to immunotherapy efficacy and the tumor microenvironment. Two cohorts were studied: a gastrectomy cohort (137 patients) and an immune checkpoint inhibitor (ICI)-treated cohort (19 patients with unresectable advanced GC who received nivolumab). Immunohistochemistry was used to assess SIRPα, CD80, CD163, CD8, and PD-L1 expressions. Kaplan-Meier curves and Cox models were used to analyze the clinical outcomes. In vitro experiments used peripheral blood mononuclear cells and THP-1 macrophage cell lines to examine SIRPα responses to interferon-γ (IFN-γ). In the gastrectomy cohort, high SIRPα expression correlated with advanced tumor invasion, distant metastasis, and poor recurrence-free and overall survival. SIRPα expression was also significantly associated with macrophage and CD8 + T cells infiltration and PD-L1 expression. In the ICI-treated cohort, high SIRPα expression was associated with better overall survival after nivolumab induced. Moreover, in vitro IFN-γ stimulation upregulated SIRPα expression on monocytes in peripheral blood mononuclear cells and THP-1 cells, suggesting high SIRPα expression may reflect an active immune microenvironment. SIRPα expression is not only a poor prognostic factor for GC, possibly through inhibition of the CD47-SIRP⍺ pathway, but may also be involved in the efficacy of ICI therapy in GC.

Sappanone A Ameliorates Concanavalin A-induced Immune-Mediated Liver Injury by Regulating M1 Macrophage Polarization.

Sappanone A (SAP), a high-isoflavone compound derived from the traditional Chinese medicine Sumu, exhibits various pharmacological activities, including anti-inflammatory and anti-oxidant effects. However, its protective effects on the liver have rarely been reported. The aim of this study was to investigate the effects of SAP on immune-mediated liver injury induced by concanavalin A (Con A) in mice and to explore the underlying molecular mechanisms. Mice were administered SAP intraperitoneally (50mg/kg body weight). Three hours later, Con A (18mg/kg) was injected via the tail vein to induce liver damage. Livers and blood were collected 12h after Con A challenge. Liver cell apoptosis, oxidative stress, and M1 macrophage activation in vivo were investigated. Bone marrow-derived macrophages were used to confirm the effects of SAP on M1 polarization in vitro. The results indicated thatSAP decreased transaminase levels, inhibited apoptosis, and improved oxidative stress in mouse livers. Furthermore, SAP significantly reduced the proportion of macrophages, inhibited the expression of CD86, and downregulated the expression of M1 macrophage-related inflammatory cytokines. Moreover, SAP-treated macrophages alleviated liver damage caused by Con A compared to non-SAP-treated macrophages. Mechanistically, SAP inhibited the phosphorylation of key molecules in the MAPK and NF-κB signaling pathways in macrophages, resulting in an inhibitory effect on M1 macrophage activation. Taken together,SAP alleviates immune-mediated liver injury induced by Con A by suppressing M1 macrophage polarization, which is partially associated with NF-κB and MAPK signaling pathways.