Expression Of Costimulatory Molecules Research Articles

Human chorionic gonadotropin regulates cytokine production by lymphocytes from patients with multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system (CNS) that primarily affects young adults, predominantly females. This was partially attributed to sex differences in immunity, which are influenced by changes in sex hormones occurring during women‘s life, among other factors. Furthermore, MS patients experience significant improvement in their symptoms during pregnancy when levels of female sex-hormones significantly increase. This phenomenon was attributed to immune adaptations occurring during gestation which are regulated by paternal antigens and sex hormones. The human chorionic gonadotropin (hCG) was shown to have strong immunosuppressive abilities. We aimed to analyze here the capacity of the hCG to regulate pro- and anti-inflammatory cytokine production by PBMC from MS patients. PBMC isolated from 17 MS patients receiving IFNβ1a treatment were cultured with or without recombinant or urinary hCG. Cytokine production in the supernatants was assessed using a CBA array and cytokine production by lymphocytes and expression of co-stimulatory molecules in B-lymphocytes were evaluated by flow cytometry. hCG reduced the production of TNF by PBMC from MS patients while lowering the percentages of TNF producing T cells and diminishing the production of TNF by B cells. hCG significantly boosted the production of IL-10 by regulatory T cells and CD19high B cells from MS patients. Furthermore, hCG treatment lowered the percentages of CD80+CD86+ expressing B cells within PBMC from MS patients. Overall, our results described a novel and not yet explored mechanisms of action of hCG in the context of MS.

Assessment of immunomodulatory effects of five commonly used parabens on human THP-1 derived macrophages: Implications for ecological and human health impacts

Parabens are widely used as broad-spectrum anti-microbials and preservatives in food, cosmetics, pharmaceuticals, and personal care products. Studies suggest that the utilization of parabens has substantially increased over the past years, particularly during the global pandemic of coronavirus disease 2019 (COVID-19). Although parabens are generally recognized as safe by the U.S. FDA, some concerns have been raised regarding the potential health effects of parabens associated with immunotoxicity. Herein, we comprehensively investigated several key characteristics of immunotoxicants of five commonly used parabens (methyl-, ethyl-, propyl-, butyl-, and benzyl parabens) in human THP-1 derived macrophages, which are effector cells serving as a first line of host defense against pathogens and tumor immunosurveillance. The results indicate parabens, at concentrations found in humans and biota, significantly dampened macrophage chemotaxis and secretion of major pro-inflammatory cytokines (TNF-α and IL-6) and anti-inflammatory cytokine (IL-10), corroborating the mRNA expression profile. Furthermore, some parabens were found to markedly alter macrophage adhesion and cell surface expression of costimulatory molecules, CD80+ and CD86+, and significantly increase macrophage phagocytosis. Collectively, these findings heighten awareness of potential immunotoxicity posed by paraben exposure at biologically relevant concentrations, providing implications for human health and ecological risks associated with immune dysfunctions.

Expression of CD226 on γδ T cells is lower in advanced chronic lymphocytic leukemia and correlates with IgA, IgG and LDH levels.

Gamma-delta (γδ) T cells comprise an important subset of human T cells, responding to viral and bacterial infections, and are significant for cancer immunosurveillance. Human γδ T cells are divided into 5 major subsets, namely Vδ1-Vδ5, of which the latter 3 have limited available literature. At present, Vδ2 is the most studied subpopulation. In the current paper, we focused on non-Vδ2 cells in chronic lymphocytic leukemia (CLL). We assessed the expression of co-inhibitory checkpoint receptors (CTLA-4, PD-1 and TIGIT) and co-stimulatory (CD226 and NKp30) molecules separately on Vδ1 and Vδ3-Vδ5 cells. We assessed γδ T cells for their expression of both cytotoxicity-related (NKp30, CD226) and co-inhibitory (PD-1, TIGIT) molecules with flow cytometry in CLL patients. Moreover, we evaluated the expression of TIGIT and CD226 ligand (PVR , CD155) in neoplastic B cells in CLL patients with quantitative real-time polymerase chain reaction (qPCR). A significant accumulation of Vδ1 T cells was noted, while no difference was observed in the total percentage of Vδ2 cells. Contrary to our initial hypothesis, the impact of CLL burden on CD226 and TIGIT expression was lower than anticipated. The former tends to be lower in more advanced disease. Finally, a strong upregulation of CD155 (PVR) was noted on CLL-derived B cells when compared to healthy B cells. Chronic lymphocytic leukemia regulates the expression of the CD155-CD226/TIGIT axis. Contrary to expectations, the ligand is significantly more affected than the receptors. Nevertheless, the relatively high expression of CD155 and TIGIT makes CLL an interesting target for anti-TIGIT immunotherapy.

HLA-DRB5 promotes immune thrombocytopenia via activating CD8+ T cells.

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by a low platelet (PLT) count and a high risk of bleeding, the clinical treatment for which still needs to be upgraded. Based on the critical role of human leukocyte antigen class II heterodimer β5 (HLA-DRB5) in immune system, we herein investigated its effect on ITP. ITP murine models were established by the injection of guinea pig anti-mouse platelet serum (GP-APS), and the PLT of mouse peripheral blood was counted during the modeling. Quantitative real-time reverse transcription polymerase chain reaction, western blot and immunofluorescence assay was performed to quantify expressions of HLA-DRB5, major histocompatibility complex II (MHC-II) and co-stimulatory molecules (CD80, CD86). Flow cytometry was conducted to analyze the percentage of CD8+ T cells. As a result, the PLT count was decreased in mouse peripheral blood. Expressions of HLA-DRB5, MHC-II and co-stimulatory molecules, as well as the percentage of CD8+ T cells were elevated in peripheral blood of ITP mice. HLA-DRB5 knockdown mitigated ITP by increasing peripheral PLT level, downregulating expressions of MHC-II and co-stimulatory molecules and inactivating CD8+ T cells. Collectively, the downregulation of HLA-DRB5 restores the peripheral PLT count in ITP mice by reducing MHC-II-mediated antigen presentation of macrophages to inhibit the activation of CD8+ T cells.

Immunological insights into hypertension: unraveling triggers and potential therapeutic avenues.

Hypertension remains the leading cause of morbidity and mortality worldwide. Despite its prevalence, the development of novel antihypertensive therapies has only recently accelerated, with novel agents not yet commercialized, leaving a substantial proportion of individuals resistant to existing treatments. The intricate pathophysiology of hypertension is now understood to involve chronic low-grade inflammation, which places the immune system in the spotlight as a potential target for new therapeutics. This review explores the factors that initiate and sustain an immune response in hypertension, offering insights into potential targets for new treatments. Several factors contribute to immune activation in hypertension, including diet and damage-associated molecular pattern (DAMP) generation. Diets rich in fat or sodium can promote inflammation by inducing intestinal barrier dysfunction and triggering salt-sensitive receptors in T cells and dendritic cells. DAMPs, such as extracellular adenosine triphosphate and heat-shock protein 70, are released during episodes of increased blood pressure, contributing to immune cell activation and inflammation. Unconventional innate-like γδ T cells contribute to initiating and maintaining an immune response through their potential involvement in antigen presentation and regulating cytokine-mediated responses. Immunologic memory, sustained through the formation of effector memory T cells after exposure to hypertensive insults, likely contributes to maintaining an immune response in hypertension. When exposed to hypertensive insults, these memory cells are rapidly activated and contribute to elevated blood pressure and end-organ damage. Evidence from human hypertension, although limited, supports the relevance of distinct immune pathways in hypertension, and highlights the potential of targeted immune interventions in human hypertension. Diet and acute bouts of high blood pressure result in the release of dietary triggers, neoantigens, and damage-associated molecular patterns (DAMPs), which promote immune system activation. Elements such as lipopolysaccharides (LPS), sodium, heat-shock protein (HSP)70, extracellular adenosine triphosphate (eATP), and growth arrest-specific 6 (GAS6) promote activation of innate immune cells such as dendritic cells (DCs) and monocytes (Mo) through their respective receptors (toll-like receptor [TLR]4, amiloride-sensitive epithelial sodium channel [ENaC], TLR2/4, P2X7 receptor [P2RX7], and Axl) leading to costimulatory molecule expression and interleukin (IL)-1β and IL-23 production. The neoantigens HSP70 and isolevuglandins (IsoLGs) are presented to T cells by DCs and possibly γδ T cells, triggering T cell activation, IL-17 and interferon (IFN)-γ production, and the formation of T effector memory (TEM) cells in the kidney, perivascular adipose tissue, bone marrow, and spleen. Exposure of TEM cells to their cognate antigen or previous activating stimuli causes these cells rapid expansion and activation. Cumulatively, this inflammatory state contributes to hypertension and end-organ damage. The figure was created using images from smart.servier.com and is licensed under a Creative Commons Attribution 4.0 license (CC BY 4.0).

Targeting the NS4b Antigen of West Nile Virus to the Endocytic Receptor DEC-205 to Stimulate Protective T Cell Responses to West Nile Virus Encephalitis

Abstract West Nile Virus (WNV), the primary cause of mosquito-borne neuroinvasive disease in the US, poses a significant public health threat without an approved human vaccine. DCs are pivotal in orchestrating immune responses, dictating antigen-specific effector T cell activation or tolerance based on their maturity. The endocytic receptor DEC-205, expressed by specific DC subsets, facilitates antigen uptake, processing, and cross-presentation, initiating an effective T cell response. Studies highlight DEC-205+ DCs within the CNS in reactivating antiviral effector T cell responses, restricting WNV replication, and mitigating immunopathology. We propose targeting antigens to these DCs to enhance antiviral immunity against WNV within the CNS, fusing antigens to DEC-205-specific monoclonal antibodies (mAbs). A DEC-205-targeted hybrid antibody will be developed, conjugating the WNV NS4b immunodominant peptide to a DEC-205 mAb. Subsequent purification will precede testing therapeutic efficacy in a murine WNV encephalitis model. Delivering the aDEC-205 hybrid mAb with DC maturation stimulus (poly I:C), we will assess co-stimulatory molecule expression (CD40, CD80, and CD86) on DCs and evaluate T cell activation through activation marker expression and cytokine production. This research introduces a vaccination approach against West Nile Virus encephalitis, leveraging targeted antigen delivery to DEC-205+ DCs, offering insights into potential therapeutic and preventive strategies.

Group 2 innate lymphoid cells are key in lipid transfer protein allergy pathogenesis.

Immunopathology in food allergy is characterized by an uncontrolled type 2 immune response and specific-IgE production. Recent studies have determined that group 2 innate lymphoid cells (ILC2) participate in the food allergy pathogenic mechanism and their severity. Our objective was to investigate the role of ILC2 in peach-allergic patients due to non-specific lipid transfer protein (Pru p 3) sensitization. The immune response in peripheral blood mononuclear cells was characterized in lipid transfer protein-allergic patients and healthy controls. We have analyzed the Pru p 3 uptake on ILC2, the expression of costimulatory molecules, and their involvement on the T-cell proliferative response and cytokine production under different experimental conditions: cytokines involved in group 2 innate lymphoid cell activation (IL-33 and IL-25), Pru p 3 as main food allergen, and the combination of both components (IL-33/IL-25+Pru p 3) using cell sorting, EliSpot, flow cytometry, and confocal microscopy. Our results show that Pru p 3 allergen is taken up by group 2 innate lymphoid cells, regulating their costimulatory molecule expression (CD83 and HLA-DR) depending on the presence of Pru p 3 and its combination with IL-33/IL-25. The Pru p 3-stimulated ILC2 induced specific GATA3+Th2 proliferation and cytokine (IL-4, IL-5, and IL-13) production in lipid transfer protein-allergic patients in a cell contact-dependent manner with no changes in Tbet+Th1- and FOXP3+Treg cell differentiation. The results indicate that in lipid transfer protein-allergic patients, the responsible allergen, Pru p 3, interacts with group 2 innate lymphoid cells, promoting a Th2 cell response. Our results might be of interest in vivo, as they show a role of group 2 innate lymphoid cells as antigen-presenting cells, contributing to the development of food allergy. Consequently, group 2 innate lymphoid cells may be considered as potential therapeutic targets.

TLR5 agonist in combination with anti-PD-1 treatment enhances anti-tumor effect through M1/M2 macrophage polarization shift and CD8+ T cell priming

Immune checkpoint inhibitors have revolutionized anti-tumor therapy, notably improving treatment responses in various tumors. However, many patients remain non-responsive and do not experience benefits. Given that Toll-like receptors (TLRs) can counteract tumor immune tolerance by stimulating both innate and adaptive immune responses, TLR agonists are being explored as potential immune adjuvants for cancer treatment. In this study, we assessed the potential of enhancing the efficacy of immune checkpoint inhibitors by activating innate immunity with a TLR5 agonist. In a mouse tumor model, combination therapy with TLR5 agonist and anti-PD-1 significantly inhibited tumor growth. The TLR5 agonist shifted the balance from M2-like to M1-like macrophages and upregulated the expression of co-stimulatory molecules in macrophages. Furthermore, TLR5 agonist promoted the activation and tumor infiltration of CD8+ T cells. As a result, the TLR5 agonist augmented the anti-tumor efficacy of anti-PD-1, suggesting its potential in modulating the tumor microenvironment to enhance the anti-tumor response. Our findings point toward the possibility of optimizing immune checkpoint inhibitor therapy using TLR5 agonists.

Identification of macaque dendritic cell precursors in blood and tissue reveals their dysregulation in early SIV infection

Distinct dendritic cell (DC) subsets play important roles in shaping immune responses. Circulating DC precursors (pre-DCs) are more susceptible to HIV infection invitro, which may explain the inefficiency of immune responses against HIV. However, the interplay between HIV and pre-DC is not defined invivo. We identify human pre-DC equivalents in the cynomolgus macaque and then analyze their dynamics during simian immunodeficiency virus (SIV) infection to illustrate a sharp decrease of blood pre-DCs in early SIV infection and accumulation in lymph nodes (LNs), where they neglect to upregulate CD83/CD86 or MHC-II. Additionally, SIV infection attenuates the capacity of stimulated LN pre-DCs to produce IL-12p40. Analysis of HIV cohorts provides correlation between costimulatory molecule expression on pre-DCs and Tcell activation in spontaneous HIV controllers. These findings pinpoint certain dynamics and functional changes of pre-DCs during SIV infection, providing a deeper understanding of immune dysregulation mechanisms elicited in people living with HIV.

Abstract 6744: Activating anti-MDS immunity with polarized dendritic cell vaccines

Abstract Less than 50% of patients with higher-risk myelodysplastic syndromes (MDS) show clinical response to standard-of-care hypomethylating (HMA) therapy. Significant enthusiasm existed for immunotherapy/HMA combinations for these patients, but studies have failed to deliver on the initial promise. We have demonstrated that patients with MDS have a deficiency in antigen-presenting cells, called CD141Hi dendritic cells (DC). DC-deficient MDS patients have reduced response to HMAs, worse overall survival, and show less response to cancer vaccination. We hypothesized that restoration of this population using a novel DC vaccination approach - alpha-type-1 polarized dendritic cells (αDC1) - might compensate for this deficiency and restore immunity. To generate αDC1s, we collected monocytes from MDS patients and healthy donors (HD) and cultured them for 6 days in vitro in the presence of recombinant human GM-CSF and IL-4 followed by an additional 18-24 hours in the presence of αDC1 maturation factors (poly-I:C/IFNα/IFNγ/TNFα/IL-1β). Overall, we attempted to generate αDC1s from 15 MDS samples; 13/15 exhibited intermediate to very high-risk disease and 10/15 are currently receiving HMA therapy. We successfully cultured cells from 8/15 samples (53%). Of the 8 MDS samples, 5 were collected from patients receiving HMA therapy (62.5%). We were unable to successfully culture αDC1s from the other 5 patients receiving HMA therapy, and thus the effect of HMA therapy on aDC1 generation remains unclear. To test the function of MDS αDC1s, we focused on two signals necessary to activate immune responses: 1) the expression of co-stimulatory molecules and 2) the production of IL-12p70. Flow cytometric analysis on αDC1s and immature DCs from MDS samples revealed intra-patient variation in the fold-change surface expression of CD40/80/83/86 and HLA-DR proteins. Additionally, there was a trend towards decreased up-regulation of CD80 and CD86 in MDS specimens compared to HD. To assess production of IL-12p70, we stimulated immature DCs and αDC1s with CD40L and performed ELISA analysis on the media supernatant. We found that 3 out of 4 samples could produce IL-12p70 (range 27 - 5,480 pg/ml). To date, our results suggest that generation of MDS patient-derived αDC1 cells is feasible and additional work is being performed to fully characterize their ability to activate anti-MDS immune responses. Since αDC1s have an established safety profile in patients with solid tumors, we anticipate that we will be able to rapidly translate our results to the clinic. Citation Format: Daniel Alvarado, Jennifer Peresie, Adam Brinkman, Cheryl Allen, Weijian Jiang, Pawel Kalinski, Tiffany Tanaka, Elizabeth Griffiths, Michael Nemeth. Activating anti-MDS immunity with polarized dendritic cell vaccines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6744.

Abstract 6753: Bria-OTS immunotherapy platform: Harnessing gene-modified tumor cells to reinvigorate the cancer immunity cycle for precision anti-tumor responses

Abstract Background: For an immune response to lead to an effective anti-tumor response, a series of stepwise events involving a complex network of iterative cellular and molecular interactions must take place. Cancer, however, often derails this immune cycle, prompting contemporary cancer immunotherapy approaches to seek its reinstatement. Despite significant advances, the inherent disruption of the cancer immunity cycle at multiple junctures, coupled with current therapeutic strategies focusing on isolated stages within this intricate process, has left the attainment of curative therapies as an aspirational goal. We believe that targeting multiple immune processes can restore natural anti-cancer immunity and yield sustained responses. To this end, BriaCell is utilizing gene-modified tumor cells as an immunotherapeutic platform. Our initial version, SV-BR-1-GM, a breast cancer cell line expressing GM-CSF, demonstrates promising clinical outcomes by directly activating CD4+ T-cells in an antigen-specific, HLA-restricted manner. Building on our findings, we hypothesize that tumor cells not only supply antigens but also directly stimulate the immune system. Presenting our second-generation platform, we enhance antigen cross-presentation and direct immune activation through the expression of cytokines, co-stimulatory factors, and HLA alleles. Methods: To achieve this objective, we have developed Bria-OTS cell lines derived from various cancer types with the following genetic modifications: 1) Expression of costimulatory molecules (CD80, CD86, 4-1BBL, CD40) and immunomodulatory cytokines (GM-CSF, IFNα, IL-12 and IL-7). This modification aims to improve the cell's ability to present antigens and activate the host immune system. 2) Expanding HLA alleles to create semi-allogeneic cell lines matching at least one HLA allele across the population aims to enhance the host immune response, enabling recognition of tumor-associated antigens in the context of syngeneic HLA molecules Results: We generated four cell lines for each tumor type, and these cell lines secreted GM-CSF, IFNα, IL12 & IL7, while also expressing CD80, CD86, CD40, and different combinations of both Class I and Class II HLA alleles. In functional assays, our cell lines demonstrated potent antigen presentation, effectively triggering anti-tumor immune responses across diverse immune populations, including T-, NK, and NKT cells. Conclusions: The Bria-OTS cell lines will offer the following key features: 1) multimodal mechanisms of action including thwarting some mechanisms of cancer immune escape. 2) Precision Therapy; Bria-OTS will be precisely matched to individual patients based on their HLA alleles, encompassing over 99% of the U.S. population. 3) rapid, cost-effective treatment as our 'off-the-shelf' cell lines eliminate the need for personalized manufacturing. Citation Format: Miguel A. Lopez-Lago, Vikas Bhardwaj, Pravin Kesarwani, Xiaoyi Zheng, Sagarika Pachhal, Patience Cournoo, Renee Cortez, Charles L. Wiseman, William V. Williams. Bria-OTS immunotherapy platform: Harnessing gene-modified tumor cells to reinvigorate the cancer immunity cycle for precision anti-tumor responses [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6753.

Abstract 1604: Cancer-associated fibroblasts modulate T cell killing activity & phenotype in PDAC

Abstract Background: Pancreatic ductal adenocarcinoma (PDAC) is highly aggressive malignancy characterised by its abundant extracellular matrix and diverse stromal cell components such as cancer associated fibroblasts (CAFs). CAFs play a pivotal role in shaping the tumour microenvironment and influencing the behaviour of immune cells, particularly T cells, through various mechanisms. The impact of CAFs on T cells is multifaceted as they can exert both pro- and anti-tumoral effects, influencing the delicate balance between immunosurveillance and immune evasion. In this study, we examined the phenotype and function of T cells when co-cultured with CAFs and Adjacent-normal fibroblasts (ANF) isolated from primary PDAC tissue following surgical resection. Methods: Tumour and juxta-tumoral tissue from patients underwent digestion into a single cell suspension. Subsequently, the isolated fibroblasts were cultured and stained with a 22-plex antibody panel designed for flow cytometry. Additional functional assays involved co-culture of CAFs and ANFs with unstimulated or anti-CD3/CD28 stimulated allogeneic T cells. Cell proliferation rates were quantified through the CFSE assay, while the T cells were simultaneously stained to distinguish CD4+ and CD8+ T cells subpopulations. Additionally, the expression of key co-stimulatory molecules: CD69, NKG2D and DNAM-1 and the co-inhibitory molecule: PD-1 were assessed, providing a thorough examination of the immune dynamics within the tumour microenvironment. Results: Flow Cytometry analysis revealed a distinct expression profile in CAFs compared to ANFs, with CAFs expressing higher levels of FAP and CD29. The CFSE assay further revealed that CAFs induced T cell proliferation of resting T cells with no significant increase in stimulated T cells. Notably, this co-culture led to a highly differentiated phenotype in both unstimulated and stimulated CD4+ and CD8+ T cells, characterised by elevated expression of activating markers (CD69 and NKG2D) and the inhibitory molecule PD-1. These findings suggest a dynamic interplay between fibroblasts and T cells in the tumour microenvironment, influencing both the proliferation and phenotypic aspects of T cell behaviour. Citation Format: Fouzia Zayou, Hayden Pearce, Samantha Nicol, Sandra Margielewska-Davies, Sarah Powell-Brett, Rachel Brown, Jianmin Zuo, Keith Roberts, Helen M. McGettrick, Paul Moss. Cancer-associated fibroblasts modulate T cell killing activity & phenotype in PDAC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1604.

Shared and distinct genetics of pure type 1 diabetes and type 1 diabetes with celiac disease, homology in their auto-antigens and immune dysregulation states: a study from North India.

This study was undertaken to explicate the shared and distinctive genetic susceptibility and immune dysfunction in patients with T1D alone and T1D with CD (T1D + CD). A total of 100 T1D, 50 T1D + CD and 150 healthy controls were recruited. HLA-DRB1/DQB1 alleles were determined by PCR-sequence-specific primer method, SNP genotyping for CTLA-4 and PTPN22 was done by simple probe-based SNP-array and genotyping for INS-23 Hph1 A/T was done by RFLP. Autoantibodies and cytokine estimation was done by ELISA. Immune-regulation was analysed by flow-cytometry. Clustering of autoantigen epitopes was done by epitope cluster analytical tool. Both T1D alone and T1D + CD had a shared association of DRB1*03:01, DRB1*04, DRB3*01:07/15 and DQB1*02. DRB3*01:07/15 confers the highest risk for T1D with relative risk of 11.32 (5.74-22.31). Non-HLA gene polymorphisms PTPN22 and INS could discriminate between T1D and T1D + CD. T1D + CD have significantly higher titers of autoantibodies, expression of costimulatory molecules on CD4 and CD8 cells, and cytokine IL-17A and TGF-β1 levels compared to T1D patients. Epitopes from immunodominant regions of autoantigens of T1D and CD clustered together with 40% homology. Same HLA genes provide susceptibility for both T1D and CD. Non-HLA genes CTLA4, PTPN22 and INS provide further susceptibility while different polymorphisms in PTPN22 and INS can discriminate between T1D and T1D + CD. Epitope homology between autoantigens of two diseases further encourages the two diseases to occur together. The T1D + CD being more common in females along with co-existence of thyroid autoimmunity, and have more immune dysregulated state than T1D alone.

Long-chain acyl-CoA synthetase 4-mediated mitochondrial fatty acid metabolism and dendritic cell antigen presentation.

This study aims to investigate the role of Acyl-CoA synthetase 4 (ACSL4) in mediating mitochondrial fatty acid metabolism and dendritic cell (DC) antigen presentation in the immune response associated with asthma. RNA sequencing was employed to identify key genes associated with mitochondrial function and fatty acid metabolism in DCs. ELISA was employed to assess the levels of fatty acid metabolism in DCs. Mitochondrial morphology was evaluated using laser confocal microscopy, structured illumination microscopy, and transmission electron microscopy. Flow cytometry and immunofluorescence were utilized to detect changes in mitochondrial superoxide generation in DCs, followed by immunofluorescence co-localization analysis of ACSL4 and the mitochondrial marker protein COXIV. Subsequently, pathological changes and immune responses in mouse lung tissue were observed. ELISA was conducted to measure the levels of fatty acid metabolism in lung tissue DCs. qRT-PCR and western blotting were employed to respectively assess the expression levels of mitochondrial-associated genes (ATP5F1A, VDAC1, COXIV, TFAM, iNOS) and proteins (ATP5F1A, VDAC1, COXIV, TOMM20, iNOS) in lung tissue DCs. Flow cytometry was utilized to analyze changes in the expression of surface antigens presented by DCs in lung tissue, specifically the MHCII molecule and the co-stimulatory molecules CD80/86. The sequencing results reveal that ACSL4 is a crucial gene regulating mitochondrial function and fatty acid metabolism in DCs. Inhibiting ACSL4 reduces the levels of fatty acid oxidases in DCs, increases arachidonic acid levels, and decreases A-CoA synthesis. Simultaneously, ACSL4 inhibition leads to an increase in mitochondrial superoxide production (MitoSOX) in DCs, causing mitochondrial rupture, vacuolization, and sparse mitochondrial cristae. In mice, ACSL4 inhibition exacerbates pulmonary pathological changes and immune responses, reducing the fatty acid metabolism levels within lung tissue DCs and the expression of mitochondria-associated genes and proteins. This inhibition induces an increase in the expression of MHCII antigen presentation molecules and co-stimulatory molecules CD80/86 in DCs. The research findings indicate that ACSL4-mediated mitochondrial fatty acid metabolism and dendritic cell antigen presentation play a crucial regulatory role in the immune response of asthma. This discovery holds promise for enhancing our understanding of the mechanisms underlying asthma pathogenesis and potentially identifying novel targets for its prevention and treatment.

Site-specific regulation of Th2 differentiation within lymph node microenvironments.

T helper 2 (Th2) responses protect against pathogens while also driving allergic inflammation, yet how large-scale Th2 responses are generated in tissue context remains unclear. Here, we used quantitative imaging to investigate early Th2 differentiation within lymph nodes (LNs) following cutaneous allergen administration. Contrary to current models, we observed extensive activation and "macro-clustering" of early Th2 cells with migratory type-2 dendritic cells (cDC2s), generating specialized Th2-promoting microenvironments. Macro-clustering was integrin-mediated and promoted localized cytokine exchange among T cells to reinforce differentiation, which contrasted the behavior during Th1 responses. Unexpectedly, formation of Th2 macro-clusters was dependent on the site of skin sensitization. Differences between sites were driven by divergent activation states of migratory cDC2 from different dermal tissues, with enhanced costimulatory molecule expression by cDC2 in Th2-generating LNs promoting prolonged T cell activation, macro-clustering, and cytokine sensing. Thus, the generation of dedicated Th2 priming microenvironments through enhanced costimulatory molecule signaling initiates Th2 responses in vivo and occurs in a skin site-specific manner.

Modulation of Dendritic Cell Function via Nanoparticle-Induced Cytosolic Calcium Changes.

Calcium nanoparticles have been investigated for applications, such as drug and gene delivery. Additionally, Ca2+ serves as a crucial second messenger in the activation of immune cells. However, few studies have systematically studied the effects of calcium nanoparticles on the calcium levels and functions within immune cells. In this study, we explore the potential of calcium nanoparticles as a vehicle to deliver calcium into the cytosol of dendritic cells (DCs) and influence their functions. We synthesized calcium hydroxide nanoparticles, coated them with a layer of silica to prevent rapid degradation, and further conjugated them with anti-CD205 antibodies to achieve targeted delivery to DCs. Our results indicate that these nanoparticles can efficiently enter DCs and release calcium ions in a controlled manner. This elevation in cytosolic calcium activates both the NFAT and NF-κB pathways, in turn promoting the expression of costimulatory molecules, antigen-presenting molecules, and pro-inflammatory cytokines. In mouse tumor models, the calcium nanoparticles enhanced the antitumor immune response and augmented the efficacy of both radiotherapy and chemotherapy without introducing additional toxicity. Our study introduces a safe nanoparticle immunomodulator with potential widespread applications in cancer therapy.

Tissue-plasminogen activator effects on the phenotype of splenic myeloid cells in acute inflammation

Tissue-plasminogen activator (tPA) is a serine protease well known for its fibrinolytic function. Recent studies indicate that tPA could also modulate inflammation via plasmin generation and/or by receptor mediated signalling in vitro. However, the contribution of tPA in inflammatory processes in vivo has not been fully addressed. Therefore, using tPA-deficient mice, we have analysed the effect of lipopolysaccharide (LPS) challenge on the phenotype of myeloid cells including neutrophils, macrophages and dendritic cells (DCs) in spleen. We found that LPS treatment upregulated the frequency of major histocompatibility class two (MHCII+) macrophages but also, paradoxically, induced a deep downregulation of MHCII molecule level on macrophages and on conventional dendritic cells 2 (cDC2). Expression level of the CD11b integrin, known as a tPA receptor, was upregulated by LPS on MHCII+ macrophages and cDC2, suggesting that tPA effects could be amplified during inflammation. In tPA−/− mice under inflammatory conditions, expression of costimulatory CD86 molecules on MHCII+ macrophages was decreased compared to WT mice, while in steady state the expression of MHCII molecules was higher on macrophages. Finally, we reported that tPA deficiency slightly modified the phenotype of DCs and T cells in acute inflammatory conditions. Overall, our findings indicate that in vivo, LPS injection had an unexpectedly bimodal effect on MHCII expression on macrophages and DCs that consequently might affect adaptive immunity. tPA could also participate in the regulation of the T cell response by modulating the levels of CD86 and MHCII molecules on macrophages.

MARCH-I: A negative regulator of dendritic cell maturation

The expression of costimulatory molecules such as MHC-II, CD86 and CD83 on dendritic cells (DCs) are strongly regulated during cellular activation. Ubiquitination of some of these markers by the E3 ubiquitin ligase MARCH-I affects the maturation state of DCs and subsequently modulates immune responses. The effects of MARCH-I gene overexpression on the functional activity of human DCs is not well understood.Here, we investigate how MARCH-I, regulates maturation of DCs. We now provide evidence that MARCH-I transduced DCs secrete high levels of IL10 despite low secretion of IL 6 and IL 12 in response to LPS stimulation. They are weak stimulators of T lymphocyte cells but skewed T cell polarization toward T regulatory subset.These results exhibit that reduced expression of surface costimulatory molecules suppresses DC activation. It can be concluded that overexpression of MARCH-I gene in DCs leads to the production of tolerogenic DC.

The Expression and Prognostic Value of Co-stimulatory Molecules in Clear Cell Renal Cell Carcinoma (CcRcc).

Renal cell carcinoma (RCC) was one of the most common malignant cancers in the urinary system. Clear cell carcinoma (ccRCC) is the most common pathological type, accounting for approximately 80% of RCC. The lack of accurate and effective prognosis prediction methods has been a weak link in ccRCC treatment. Co-stimulatory molecules played the main role in increasing anti-tumor immune response, which determined the prognosis of patients. Therefore, the main objective of the present study was to explore the prognostic value of co-stimulatory molecules genes in ccRCC patients. The TCGA database was used to get gene expression and clinical characteristics of patients with ccRCC. A total of 60 co-stimulatory molecule genes were also obtained from TCGAccRCC, including 13 genes of the B7/ CD28 co-stimulatory molecules family and 47 genes of the TNF family. In the TCGA cohort, the least absolute shrinkage and selection operator (LASSO) Cox regression model was used to generate a multigene signature. R and Perl programming languages were used for data processing and drawing. Real-time PCR was used to verify the expression of differentially expressed genes. The study's initial dataset included 539 ccRCC samples and 72 normal samples. The 13 samples have been eliminated. According to FDR<0.05, there were differences in the expression of 55 co-stimulatory molecule genes in ccRCC and normal tissues. LASSO Cox regression analysis results indicated that 13 risk genes were optimally used to construct a prognostic model of ccRCC. The patients were divided into a high-risk group and a low-risk group. Those in the high-risk group had significantly lower OS (Overall Survival rate) than patients in the low-risk group. Receiver operating characteristic (ROC) curve analysis confirmed the predictive value of the prognosis model of ccRCC (AUC>0.7). There are substantial differences in immune cell infiltration between high and low-risk groups. Functional analysis revealed that immune-related pathways were enriched, and immune status was different between the two risk groups. Real-time PCR results for genes were consistent with TCGA DEGs. By stratifying patients with all independent risk factors, the prognostic score model developed in this study may improve the accuracy of prognosis prediction for patients with ccRCC.

GSK3α/β Restrain IFN-γ-Inducible Costimulatory Molecule Expression in Alveolar Macrophages, Limiting CD4+ T Cell Activation.

Macrophages play a crucial role in eliminating respiratory pathogens. Both pulmonary resident alveolar macrophages (AMs) and recruited macrophages contribute to detecting, responding to, and resolving infections in the lungs. Despite their distinct functions, it remains unclear how these macrophage subsets regulate their responses to infection, including how activation by the cytokine IFN-γ is regulated. This shortcoming prevents the development of therapeutics that effectively target distinct lung macrophage populations without exacerbating inflammation. We aimed to better understand the transcriptional regulation of resting and IFN-γ-activated cells using a new ex vivo model of AMs from mice, fetal liver-derived alveolar-like macrophages (FLAMs), and immortalized bone marrow-derived macrophages. Our findings reveal that IFN-γ robustly activates both macrophage types; however, the profile of activated IFN-γ-stimulated genes varies greatly between these cell types. Notably, FLAMs show limited expression of costimulatory markers essential for T cell activation upon stimulation with only IFN-γ. To understand cell type-specific differences, we examined how the inhibition of the regulatory kinases GSK3α/β alters the IFN-γ response. GSK3α/β controlled distinct IFN-γ responses, and in AM-like cells, we found that GSK3α/β restrained the induction of type I IFN and TNF, thus preventing the robust expression of costimulatory molecules and limiting CD4+ T cell activation. Together, these data suggest that the capacity of AMs to respond to IFN-γ is restricted in a GSK3α/β-dependent manner and that IFN-γ responses differ across distinct macrophage populations. These findings lay the groundwork to identify new therapeutic targets that activate protective pulmonary responses without driving deleterious inflammation.