Dendritic cell subsets

FcγRI plays a pro-inflammatory role in the immune response to Chlamydia respiratory infection by upregulating dendritic cell-related genes

BACKGROUND

FcγRI, a pivotal cell surface receptor, is implicated in diverse immune responses and is ubiquitously expressed on numerous immune cells. However, its role in intracellular bacterial infections remains understudied.

METHODS

Wild-type (WT) and FcγRI knockout (FcγRI-KO) mice were inoculated intranasally with a specific dose of C. muridarum. Lung tissues were harvested for transcriptome sequencing, and flow cytometry was employed to validate bioinformatics immune infiltration analysis. Differentially expressed DC-associated genes were subjected to Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses to elucidate their functions during infection. A PPI network was constructed to pinpoint crucial genes, and qPCR was utilized to confirm their expression changes. Additionally, we compared body weight, lung Chlamydia load, and pathological alterations between WT and FcγRI-KO mice post-infection to assess the effect of FcγRI on inflammation via gene regulation. Lastly, an mRNA-miRNA-lncRNA network was formulated to further probe the molecular mechanisms of FcγRI in C. muridarum infection.

RESULTS

Post-C. muridarum infection, FcγRI-KO mice exhibited a notable decrease in DC infiltration and maturation, along with downregulated co-stimulatory molecules (CD40, CD80, CD86) in lung tissues. Differential gene analysis identified 26 differentially expressed DC-related genes implicated in DC proliferation, migration, and inflammatory responses. KEGG analysis revealed their close association with key immune pathways. The PPI network delineated two modules, with the top six genes in the pivotal cluster 1 (Ccl4, Il6, Ccl3, Ptgs2, Il 1α, Il7) being significantly downregulated in FcγRI-KO mice. A ceRNA network encompassing 12 miRNAs and 37 lncRNAs regulating four key genes (Ptgs2, Il1α, Il6, Il7) was also constructed.

CONCLUSIONS

In C. muridarum respiratory infections, FcγRI facilitates DC infiltration and maturation, upregulates six pro-inflammatory genes (Ccl4, Il6, Ccl3, Ptgs2, Il1α, Il7), and exhibits a pro-inflammatory role. A key ceRNA network was formulated to unravel the underlying molecular mechanisms.

A small-molecule enhancer of STAT1 affects herpes simplex keratitis prognosis by mediating plasmacytoid dendritic cells migration through CXCR3/CXCL10

Herpes simplex keratitis (HSK) is a prevalent infectious corneal disorder. This study aims to explore the role of plasmacytoid dendritic cells (pDCs) in HSK, an area that remains underexplored. The investigation centers on the effects of a STAT1 transcription enhancer, 2-NP, on pDCs and its underlying mechanisms. Our findings revealed that 2-NP treatment significantly reduced corneal opacity and neovascularization in a mouse HSK model. This intervention increased CXCR3 expression on the cell membrane, promoting pDC migration to the cornea via the CXCR3/CXCL10 axis. Additionally, it triggered STAT1 phosphorylation, enhancing IFN-α production, which in turn activated the JAK1/STAT1 signaling pathway. These results uncover a novel molecular mechanism by which the STAT1 transcriptional enhancer drives pDC migration to inflamed corneas, presenting a new therapeutic strategy for HSK.

Tissue-resident immune cells: from defining characteristics to roles in diseases

Tissue-resident immune cells (TRICs) are a highly heterogeneous and plastic subpopulation of immune cells that reside in lymphoid or peripheral tissues without recirculation. These cells are endowed with notably distinct capabilities, setting them apart from their circulating leukocyte counterparts. Many studies demonstrate their complex roles in both health and disease, involving the regulation of homeostasis, protection, and destruction. The advancement of tissue-resolution technologies, such as single-cell sequencing and spatiotemporal omics, provides deeper insights into the cell morphology, characteristic markers, and dynamic transcriptional profiles of TRICs. Currently, the reported TRIC population includes tissue-resident T cells, tissue-resident memory B (BRM) cells, tissue-resident innate lymphocytes, tissue-resident macrophages, tissue-resident neutrophils (TRNs), and tissue-resident mast cells, but unignorably the existence of TRNs is controversial. Previous studies focus on one of them in specific tissues or diseases, however, the origins, developmental trajectories, and intercellular cross-talks of every TRIC type are not fully summarized. In addition, a systemic overview of TRICs in disease progression and the development of parallel therapeutic strategies is lacking. Here, we describe the development and function characteristics of all TRIC types and their major roles in health and diseases. We shed light on how to harness TRICs to offer new therapeutic targets and present burning questions in this field.

The neuroimmune mechanism of pain induced depression in psoriatic arthritis and future directions

Patients suffering from psoriatic arthritis (PsA) often experience depression due to chronic joint pain, which significantly hinders their recovery process. However, the relationship between these two conditions is not well understood. Through a review of existing studies, we revealed that certain neuroendocrine hormones and neurotransmitters are involved in the neuroimmune interactions related to both PsA and depression. These include adrenocorticotropin-releasing hormone (CRH), adrenocorticotropin (ACTH), cortisol, monoamine neurotransmitters, and brain-derived neurotrophic factor (BDNF). Notably, the signalling pathway involving CRH, MCs, and Th17 cells plays a crucial role in linking PsA with depression; thus, this pathway may help clarify their connection. In this review, we outline the inflammatory immune changes associated with PsA and depression. Additionally, we explore how neuroendocrine hormones and neurotransmitters influence inflammatory responses in these two conditions. Finally, our focus will be on potential treatment strategies for patients with PsA and depression through the targeting of the CRH-MC-Th17 pathway. This review aims to provide a theoretical framework as well as new therapeutic targets for managing PsA alongside depression.

Resveratrol promotes cholesterol efflux from dendritic cells and controls costimulation and T-cell activation in high-fat and lipopolysaccharide-driven atherosclerotic mice

Cholesterol aggregation in dendritic cells (DCs) triggers an inflammatory response and accelerates the development of atherosclerosis (AS). Resveratrol (RES), a natural compound with anti-inflammatory and cholesterol metabolism regulatory properties, has been shown to influence the maturation and inflammatory functions of DCs. However, its relationship with cholesterol metabolism remains unclear. This study aimed to explore the roles of RES in cholesterol metabolism and inflammatory behaviors of DCs in the context of AS. We analyzed the effect of RES on cholesterol efflux from ApoE-/- bone marrow-derived dendritic cells (BMDCs) using qRT-PCR, Western blot, and cholesterol efflux assays; identified the inflammatory status of RES-treated BMDCs and co-cultured T cells using flow cytometry and ELISA; confirmed the effect of RES on blood lipids, atherosclerotic lesions, cholesterol metabolism, and inflammatory response in high-fat diet and lipopolysaccharide-treated ApoE-/- mice; and explored the potential targets of RES in regulating inflammatory behavior via molecular docking. The results revealed that RES promotes cholesterol efflux, increases the expression of efflux transporter ABCA1, and decreases liver X receptor alpha (LXRα) expression in response to a decrease in intracellular cholesterol in ApoE-/- BMDCs. RES also reduced MHC-II+ cells and downregulated costimulatory molecule CD80 in BMDCs with decreased IL-6 and increased IL-2 production, and suppressed T-cell activation and modulates IL-22 and IL-10 secretion via BMDCs. Furthermore, we confirmed that RES relieves arterial lesions and regulates blood lipids in ApoE-/- mice. RES demonstrated ABCA1 upregulation and LXRα downregulation effects in the aorta and regulated costimulation molecules and Th17/Treg cytokines in the spleen. Furthermore, RES showed multiple hydrogen bonding and low binding energy with ABCA1, suggesting that ABCA1 is a potential target of RES to modulate the inflammatory properties of BMDCs. Our study demonstrated that RES regulates cholesterol efflux and inflammatory behavior in BMDCs, contributing to the control of AS progression and offering new insights for managing inflammatory diseases.

Inference and analysis of cell-cell communication of non-myeloid circulating cells in late sepsis based on single-cell RNA-seq

Sepsis is a severe systemic inflammatory syndrome triggered by infection and is a leading cause of morbidity and mortality in intensive care units (ICUs). Immune dysfunction is a hallmark of sepsis. In this study, the authors investigated cell-cell communication among lymphoid-derived leucocytes using single-cell RNA sequencing (scRNA-seq) to gain a deeper understanding of the underlying mechanisms in late-stage sepsis. The authors' findings revealed that both the number and strength of cellular interactions were elevated in septic patients compared to healthy individuals, with several pathways showing significant alterations, particularly in conventional dendritic cells (cDCs) and plasmacytoid dendritic cells (pDCs). Notably, pathways such as CD6-ALCAM were more activated in sepsis, potentially due to T cell suppression. This study offers new insights into the mechanisms of immunosuppression and provides potential avenues for clinical intervention in sepsis.

The role and molecular mechanism of Trametes Robiniophila Murr(Huaier) in tumor therapy

ETHNOPHARMACOLOGICAL RELEVANCE

Trametes Robiniophila Murr, commonly known as Huaier, has been extensively documented in ethnopharmacology research in China. Huaier has a long history of clinical usage spanning over 1000 years in China. Traditional clinical application records demonstrate the wide utilization of Huaier for treating various cancers and enhancing the autoimmunity of tumor patients.

AIM OF THE REVIEW

The present study provides a comprehensive review of the traditional uses, phytochemical constituents, pharmacological activities, anti-tumor mechanism, and potential applications of Huaier, thereby offering valuable insights for the further development and utilization of this natural product.

MATERIALS AND METHODS

This study employed the keywords "Trametes Robiniophila Murr" and "Huaier" to retrieve relevant information on Huaier from various databases, including PubMed, Web of Science, Springer, Science Direct, ACS, Wiley, CNKI, Baidu Scholar, Google Scholar, and ancient materia medica.

RESULTS

Trametes Robiniophila Murr (Huaier), a traditional Chinese medicine, has demonstrated significant efficacy in the clinical treatment of various tumors. The primary bioactive constituents of Huaier consist of fungal-derived compounds, including polysaccharides, proteins, ketones, alkaloids, and minerals. The research findings demonstrate that Huaier serves as a reliable adjunctive therapeutic agent by effectively inhibiting cancer cell proliferation, inducing apoptosis in cancer cells, suppressing tumor metastasis, regulating tumor stem cells and immune function. Therefore, it exerts a potent anti-tumor effect when used in conjunction with conventional anti-cancer therapies.

CONCLUSIONS

The analysis of traditional uses, phytochemical composition, and pharmacological activity reveals that Huaier exhibits significant potential as a medicinal plant with diverse pharmacological effects. Owing to its numerous advantages, Huaier holds immense promise for application in the domains of tumor prevention and treatment, enhancing both survival time and quality of life among cancer patients.

Immunometabolism: signaling pathways, homeostasis, and therapeutic targets

Immunometabolism plays a central role in sustaining immune system functionality and preserving physiological homeostasis within the organism. During the differentiation and activation, immune cells undergo metabolic reprogramming mediated by complex signaling pathways. Immune cells maintain homeostasis and are influenced by metabolic microenvironmental cues. A series of immunometabolic enzymes modulate immune cell function by metabolizing nutrients and accumulating metabolic products. These enzymes reverse immune cells' differentiation, disrupt intracellular signaling pathways, and regulate immune responses, thereby influencing disease progression. The huge population of immune metabolic enzymes, the ubiquity, and the complexity of metabolic regulation have kept the immune metabolic mechanisms related to many diseases from being discovered, and what has been revealed so far is only the tip of the iceberg. This review comprehensively summarized the immune metabolic enzymes' role in multiple immune cells such as T cells, macrophages, natural killer cells, and dendritic cells. By classifying and dissecting the immunometabolism mechanisms and the implications in diseases, summarizing and analyzing advancements in research and clinical applications of the inhibitors targeting these enzymes, this review is intended to provide a new perspective concerning immune metabolic enzymes for understanding the immune system, and offer novel insight into future therapeutic interventions.

The role of DC subgroups in the pathogenesis of asthma

Dendritic cells (DCs), specialized antigen-presenting cells of the immune system, act as immunomodulators in diseases of the immune system, including asthma. The understanding of DC biology has evolved over the years to include multiple subsets of DCs with distinct functions in the initiation and maintenance of asthma. Moreover, most strategies for treating asthma with relevant therapeutic agents that target DCs have been initiated from the study of DC function. We discussed the pathogenesis of asthma (including T2-high and T2-low), the roles played by different DC subpopulations in the pathogenesis of asthma, and the therapeutic strategies centered around DCs. This study will provide a scientific theoretical basis for current asthma treatment, provide theoretical guidance and research ideas for developing and studying therapeutic drugs targeting DC, and provide more therapeutic options for the patient population with poorly controlled asthma symptoms.

Engineering dendritic cell biomimetic membrane as a delivery system for tumor targeted therapy

Targeted immunotherapies make substantial strides in clinical cancer care due to their ability to counteract the tumor's capacity to suppress immune responses. Advances in biomimetic technology with minimally immunogenic and highly targeted, are addressing issues of targeted drug delivery and disrupting the tumor's immunosuppressive environment to trigger immune activation. Specifically, the use of dendritic cell (DC) membranes to coat nanoparticles ensures targeted delivery due to DC's unique ability to activate naive T cells, spotlighting their role in immunotherapy aimed at disrupting the tumor microenvironment. The potential of DC's biomimetic membrane to mediate immune activation and target tumors is gaining momentum, enhancing the effectiveness of cancer treatments in conjunction with other immune responses. This review delves into the methodologies behind crafting DC membranes and the fusion of dendritic and tumor cell membranes for encapsulating therapeutic nanoparticles. It explores their applications and recent advancements in combating cancer, offering an all-encompassing perspective on DC biomimetic nanosystems, immunotherapy driven by antigen presentation, and the collaborative efforts of drug delivery in chemotherapy and photodynamic therapies. Current evidence shows promise in augmenting combined therapeutic approaches for cancer treatment and holds translational potential for various cancer treatments in a clinical setting.

Maresin2 negatively regulates DC's maturation via the MAPK/NF-κB pathway in DCs

OBJECTIVE

To observe the effects and mechanisms of Maresin2 on the function of DCs(Dendritic cells).

METHOD

The levels of IL-6, IL-12, TNF-α and IL-1β secreted by BMDCs (Bone marrow-derived Dendritic cells) after Maresin2 treatment were detected by ELISA. At the same time, the expressions of costimulatory molecules CD40 and CD86 on the surface, the ability of phagocytosis of ovalbumin(OVA) antigen, and antigen presentation function in BMDCs were analyzed by flow cytometry. Finally, MAPK and NF-κB pathway signaling phosphorylation in Maresin2-treated BMDCs were detected by western blot.

RESULTS

The secretion levels of IL-6, IL-12, TNF-α and IL-1β were significantly decreased in the Maresin2 treatment group after LPS treatment (P < 0.05). The expression levels of CD86 and CD40 were significantly decreased after Maresin2 treatment (P < 0.05). Maresin2 enhanced the phagocytosis ability of ovalbumin(OVA) (P < 0.05), but the ability of antigen presentation of BMDCs with the treatment of Maresin2 changed slightly (P > 0.05). Phosphorylation of p38, JNK, p65, ikka/β and ERK peaked at 15 min in the LPS group, while phosphorylation of p-p38 and p-ERK weakened 30 min and 60 min after treatment with Maresin2.

CONCLUSIONS

Maresin2 inhibits inflammatory cytokine secretion but enhances phagocytosis via the MAPK/NF-κB pathway in BMDCs, which may contribute to negatively regulating inflammation.

Potential immunologic and prognostic roles of CHRNA6 in SCLC and pan-cancer

Background

Small cell lung cancer (SCLC) is considered the most malignant subtype of lung cancer, and it has a restricted range of therapeutic choices. The emergence of immunotherapy has offered new possibilities for patients with SCLC. However, the scarcity of clinical specimens has hampered the progress of clinical studies and we still face a shortage of dependable indicators to forecast the effectiveness of immunotherapy for SCLC.

Methods

In our study, we assessed the ImmuneScore and StromalScore of 81 SCLC samples obtained from the cBioPortal database. By comparing gene expression differences between the high and low immune scores groups, we identified 24 differentially expressed genes. Subsequently, an intersection was performed with genes that exhibited differential expression between normal and SCLC tissues, leading us to isolate the gene CHRNA6. To gain a deeper insight into the possible significance of CHRNA6 in SCLC, we singled out 50 genes that showed the most pronounced positive and negative associations with its expression. We then pinpointed hub genes for subsequent functional enrichment analyses by establishing a protein-protein interactions network. We additionally assessed the link between CHRNA6 expression in SCLC and characteristics of the immune microenvironment, along with the efficacy of immunotherapy, using the CIBERSORT, immunophenoscores (IPS), and tumor immune dysfunction and exclusion (TIDE) algorithms. Furthermore, we confirmed the prognostic impact of CHRNA6 expression in SCLC patients undergoing immunotherapy within a clinical cohort. Lastly, we obtained data from The Cancer Genome Atlas (TCGA) to investigate CHRNA6 expression in various tumors and its associations with genetic alterations, DNA methylation, copy number variation, clinicopathological characteristics, biological processes, immune microenvironment, prognosis, and drug sensitivity.

Results

In SCLC, we found that CHRNA6 function was associated with immune activation pathways such as antigen presentation processing and positive regulation of adaptive immune response, and that CHRNA6 demonstrated a strong correlation with immune cells infiltration. In addition, analysis of the clinical cohort revealed that patients with SCLC who exhibited elevated expression of CHRNA6 experienced better responses to immunotherapy. Our pan-cancer analysis disclosed that the expression of CHRNA6 is dysregulated in a multitude of cancers, potentially due to genetic mutations, copy number gains, and DNA demethylation. The gene set enrichment analysis (GSEA) outcomes indicated that CHRNA6 participates in immune responses and may play a positive immune regulatory role in most cancers. Furthermore, CHRNA6 has been observed to have a notable relationship with immune checkpoints, immunomodulators, immune cell infiltration, patient outcomes, and drug sensitivity across various cancers.

Conclusions

Our findings indicate that the CHRNA6 may act as a predictive indicator for SCLC patients receiving immunotherapy. The study also uncovers the aberrant expression of CHRNA6 in a range of human cancers and its potential roles in immunology and prognosis, offering novel perspectives for tailored cancer therapies.

Metabolic regulation of the immune system in health and diseases: mechanisms and interventions

Metabolism, including glycolysis, oxidative phosphorylation, fatty acid oxidation, and other metabolic pathways, impacts the phenotypes and functions of immune cells. The metabolic regulation of the immune system is important in the pathogenesis and progression of numerous diseases, such as cancers, autoimmune diseases and metabolic diseases. The concept of immunometabolism was introduced over a decade ago to elucidate the intricate interplay between metabolism and immunity. The definition of immunometabolism has expanded from chronic low-grade inflammation in metabolic diseases to metabolic reprogramming of immune cells in various diseases. With immunometabolism being proposed and developed, the metabolic regulation of the immune system can be gradually summarized and becomes more and more clearer. In the context of many diseases including cancer, autoimmune diseases, metabolic diseases, and many other disease, metabolic reprogramming occurs in immune cells inducing proinflammatory or anti-inflammatory effects. The phenotypic and functional changes of immune cells caused by metabolic regulation further affect and development of diseases. Based on experimental results, targeting cellular metabolism of immune cells becomes a promising therapy. In this review, we focus on immune cells to introduce their metabolic pathways and metabolic reprogramming, and summarize how these metabolic pathways affect immune effects in the context of diseases. We thoroughly explore targets and treatments based on immunometabolism in existing studies. The challenges of translating experimental results into clinical applications in the field of immunometabolism are also summarized. We believe that a better understanding of immune regulation in health and diseases will improve the management of most diseases.

Novel insights into immune cells modulation of tumor resistance

Tumor resistance poses a significant challenge to effective cancer treatment, making it imperative to explore new therapeutic strategies. Recent studies have highlighted the profound involvement of immune cells in the development of tumor resistance. Within the tumor microenvironment, macrophages undergo polarization into the M2 phenotype, thus promoting the emergence of drug-resistant tumors. Neutrophils contribute to tumor resistance by forming extracellular traps. While T cells and natural killer (NK) cells exert their impact through direct cytotoxicity against tumor cells. Additionally, dendritic cells (DCs) have been implicated in preventing tumor drug resistance by stimulating T cell activation. In this review, we provide a comprehensive summary of the current knowledge regarding immune cell-mediated modulation of tumor resistance at the molecular level, with a particular focus on macrophages, neutrophils, DCs, T cells, and NK cells. The targeting of immune cell modulation exhibits considerable potential for addressing drug resistance, and an in-depth understanding of the molecular interactions between immune cells and tumor cells holds promise for the development of innovative therapies. Furthermore, we explore the clinical implications of these immune cells in the treatment of drug-resistant tumors. This review emphasizes the exploration of novel approaches that harness the functional capabilities of immune cells to effectively overcome drug-resistant tumors.

Traditional Chinese herbal medicine: harnessing dendritic cells for anti-tumor benefits

Chinese Herbal Medicine (CHM) is being more and more used in cancer treatment because of its ability to regulate the immune system. Chinese Herbal Medicine has several advantages over other treatment options, including being multi-component, multi-target, and having fewer side effects. Dendritic cells (DCs) are specialized antigen presenting cells that play a vital part in connecting the innate and adaptive immune systems. They are also important in immunotherapy. Recent evidence suggests that Chinese Herbal Medicine and its components can positively impact the immune response by targeting key functions of dendritic cells. In this review, we have summarized the influences of Chinese Herbal Medicine on the immunobiological feature of dendritic cells, emphasized an anti-tumor effect of CHM-treated DCs, and also pointed out deficiencies in the regulation of DC function by Chinese Herbal Medicine and outlined future research directions.

Reciprocal regulation of T follicular helper cells and dendritic cells drives colitis development

The immunological mechanisms underlying chronic colitis are poorly understood. T follicular helper (TFH) cells are critical in helping B cells during germinal center reactions. In a T cell transfer colitis model, a lymphoid structure composed of mature dendritic cells (DCs) and TFH cells was found within T cell zones of colonic lymphoid follicles. TFH cells were required for mature DC accumulation, the formation of DC-T cell clusters and colitis development. Moreover, DCs promoted TFH cell differentiation, contributing to colitis development. A lineage-tracing analysis showed that, following migration to the lamina propria, TFH cells transdifferentiated into long-lived pathogenic TH1 cells, promoting colitis development. Our findings have therefore demonstrated the reciprocal regulation of TFH cells and DCs in colonic lymphoid follicles, which is critical in chronic colitis pathogenesis.

NETosis of psoriasis: a critical step in amplifying the inflammatory response

NETosis, a regulated form of neutrophil death, is crucial for host defense against pathogens. However, the release of neutrophil extracellular traps (NETs) during NETosis can have detrimental effects on surrounding tissues and contribute to the pro-inflammatory response, in addition to their role in controlling microbes. Although it is well-established that the IL-23-Th17 axis plays a key role in the pathogenesis of psoriasis, emerging evidence suggests that psoriasis, as an autoinflammatory disease, is also associated with NETosis. The purpose of this review is to provide a comprehensive understanding of the mechanisms underlying NETosis in psoriasis. It will cover topics such as the formation of NETs, immune cells involved in NETosis, and potential biomarkers as prognostic/predicting factors in psoriasis. By analyzing the intricate relationship between NETosis and psoriasis, this review also aims to identify novel possibilities targeting NETosis for the treatment of psoriasis.

Mediated Mendelian randomization analysis to determine the role of immune cells in regulating the effects of plasma metabolites on childhood asthma

Childhood asthma is a chronic inflammatory disease of the airways, the pathogenesis of which involves multiple factors including genetic predisposition, environmental exposure, and immune system regulation. To date, the causal relationships between immune cells, plasma metabolites, and childhood asthma remain undetermined. Therefore, we aim to utilize the Mendelian randomization approach to assess the causal relationships among immune cells, plasma metabolites, and childhood asthma. This study employed the Mendelian randomization approach to investigate how immune cells influenced the risk of childhood asthma by modulating the levels of plasma metabolites. Five Mendelian randomization methods-inverse variance weighted, weighted median, Mendelian randomization-Egger, simple mode, and weighted mode-were utilized to explore the causal relationships among 731 types of immune cells, 1400 plasma metabolites, and childhood asthma. The instrumental variables for the 731 immune cells and 1400 plasma metabolites were derived from a genome-wide association study meta-analysis. Additionally, sensitivity analyses were conducted to examine the robustness of the results, potential heterogeneity, and pleiotropy. The inverse variance weighted results indicated that HLA DR on dendritic cells (DC) is a risk factor for childhood asthma (OR: 1.08, 95% CI: 1.02-1.14). In contrast, HLA DR on DC acts as a protective factor against elevated catechol glucuronide levels (OR: 0.94, 95% CI: 0.91-0.98), while catechol glucuronide levels themselves serve as a protective factor for childhood asthma (OR: 0.73, 95% CI: 0.60-0.89). Thus, HLA DR on DC can exert a detrimental effect on childhood asthma through the negative regulation of catechol glucuronide levels. The mediating effect was 0.018, accounting for a mediation effect proportion of 23.4%. This study found that HLA DR on DC can exert a risk effect on childhood asthma through the negative regulation of catechol glucuronide levels, providing new strategies for the prevention and treatment of childhood asthma and guiding future research and clinical practice.

Merkel Cell Carcinoma: Integrating Epidemiology, Immunology, and Therapeutic Updates

Merkel cell carcinoma (MCC) is a rare skin cancer characterized by neuroendocrine differentiation. Its carcinogenesis is based either on the integration of the Merkel cell polyomavirus or on ultraviolet (UV) mutagenesis, both of which lead to high immunogenicity either through the expression of viral proteins or neoantigens. Despite this immunogenicity resulting from viral or UV-associated carcinogenesis, it exhibits highly aggressive behavior. However, owing to the rarity of MCC and the lack of epidemiologic registries with detailed clinical data, there is some uncertainty regarding the spontaneous course of the disease. Historically, advanced MCC patients were treated with conventional cytotoxic chemotherapy yielding a median response duration of only 3 months. Starting in 2017, four programmed cell death protein 1 (PD-1)/programmed cell death-ligand 1 (PD-L1) immune checkpoint inhibitors-avelumab, pembrolizumab, nivolumab (utilized in both neoadjuvant and adjuvant settings), and retifanlimab-have demonstrated efficacy in treating patients with disseminated MCC on the basis of prospective clinical trials. However, generating clinical evidence for rare cancers, such as MCC, is challenging owing to difficulties in conducting large-scale trials, resulting in small sample sizes and therefore lacking statistical power. Thus, to comprehensively understand the available clinical evidence on various immunotherapy approaches for MCC, we also delve into the epidemiology and immune biology of this cancer. Nevertheless, while randomized studies directly comparing immune checkpoint inhibitors and chemotherapy in MCC are lacking, immunotherapy shows response rates comparable to those previously reported with chemotherapy but with more enduring responses. Notably, adjuvant nivolumab has proven superiority to the standard-of-care therapy (observation) in the adjuvant setting.

TIMP-1 is an activator of MHC-I expression in myeloid dendritic cells with implications for tumor immunogenicity

Immune checkpoint therapies (ICT) for advanced solid tumors mark a new milestone in cancer therapy. Yet their efficacy is often limited by poor immunogenicity, attributed to inadequate priming and generation of antitumor T cells by dendritic cells (DCs). Identifying biomarkers to enhance DC functions in such tumors is thus crucial. Tissue Inhibitor of Metalloproteinases-1 (TIMP-1), recognized for its influence on immune cells, has an underexplored relationship with DCs. Our research reveals a correlation between high TIMP1 levels in metastatic melanoma and increased CD8 + T cell infiltration and survival. Network studies indicate a functional connection with HLA genes. Spatial transcriptomic analysis of a national melanoma cohort revealed that TIMP1 expression in immune compartments associates with an HLA-A/MHC-I peptide loading signature in lymph nodes. Primary human and bone-marrow-derived DCs secrete TIMP-1, which notably increases MHC-I expression in classical type 1 dendritic cells (cDC1), especially under melanoma antigen exposure. TIMP-1 affects the immunoproteasome/TAP complex, as seen by upregulated PSMB8 and TAP-1 levels of myeloid DCs. This study uncovers the role of TIMP-1 in DC-mediated immunogenicity with insights into CD8 + T cell activation, providing a foundation for mechanistic exploration and highlighting its potential as a new target for combinatorial immunotherapy to enhance ICT effectiveness.

Dysregulated dendritic cells in sepsis: functional impairment and regulated cell death

Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Studies have indicated that immune dysfunction plays a central role in the pathogenesis of sepsis. Dendritic cells (DCs) play a crucial role in the emergence of immune dysfunction in sepsis. The major manifestations of DCs in the septic state are abnormal functions and depletion in numbers, which are linked to higher mortality and vulnerability to secondary infections in sepsis. Apoptosis is the most widely studied pathway of number reduction in DCs. In the past few years, there has been a surge in studies focusing on regulated cell death (RCD). This emerging field encompasses various forms of cell death, such as necroptosis, pyroptosis, ferroptosis, and autophagy-dependent cell death (ADCD). Regulation of DC's RCD can serve as a possible therapeutic focus for the treatment of sepsis. Throughout time, numerous tactics have been devised and effectively implemented to improve abnormal immune response during sepsis progression, including modifying the functions of DCs and inhibiting DC cell death. In this review, we provide an overview of the functional impairment and RCD of DCs in septic states. Also, we highlight recent advances in targeting DCs to regulate host immune response following septic challenge.

The protective role of prebiotics and probiotics on diarrhea and gut damage in the rotavirus-infected piglets

Rotavirus is one of the pathogenic causes that induce diarrhea in young animals, especially piglets, worldwide. However, nowadays, there is no specific drug available to treat the disease, and the related vaccines have no obvious efficiency in some countries. Via analyzing the pathogenesis of rotavirus, it inducing diarrhea is mainly due to disturb enteric nervous system, destroy gut mucosal integrity, induce intracellular electrolyte imbalance, and impair gut microbiota and immunity. Many studies have already proved that prebiotics and probiotics can mitigate the damage and diarrhea induced by rotavirus infection in hosts. Based on these, the current review summarizes and discusses the effects and mechanisms of prebiotics and probiotics on rotavirus-induced diarrhea in piglets. This information will highlight the basis for the swine production utilization of prebiotics and probiotics in the prevention or treatment of rotavirus infection in the future.

Ex Vivo-Generated Tolerogenic Dendritic Cells: Hope for a Definitive Therapy of Autoimmune Diseases

Current therapies for autoimmune diseases are immunosuppressant agents, which have many debilitating side effects. However, dendritic cells (DCs) can induce antigen-specific tolerance. Tolerance restoration mediated by ex vivo-generated DCs can be a therapeutic approach. Therefore, in this review, we summarize the conceptual framework for developing ex vivo-generated DC strategies for autoimmune diseases. First, we will discuss the role of DCs in developing immune tolerance as a foundation for developing dendritic cell-based immunotherapy for autoimmune diseases. Then, we also discuss relevant findings from pre-clinical and clinical studies of ex vivo-generated DCs for therapy of autoimmune diseases. Finally, we discuss problems and challenges in dendritic cell therapy in autoimmune diseases. Throughout the article, we discuss autoimmune diseases, emphasizing SLE.

Enhancement of SARS-CoV-2 mRNA Vaccine Efficacy through the Application of TMSB10 UTR for Superior Antigen Presentation and Immune Activation

The development of effective vaccines against SARS-CoV-2 remains a critical challenge amidst the ongoing global pandemic. This study introduces a novel approach to enhancing mRNA vaccine efficacy by leveraging the untranslated region (UTR) of TMSB10, a gene identified for its significant mRNA abundance in antigen-presenting cells. Utilizing the GEO database, we identified TMSB10 among nine genes, with the highest mRNA abundance in dendritic cell subtypes. Subsequent experiments revealed that TMSB10's UTR significantly enhances the expression of a reporter gene in both antigen-presenting and 293T cells, surpassing other candidates and a previously optimized natural UTR. A comparative analysis demonstrated that TMSB10 UTR not only facilitated a higher reporter gene expression in vitro but also showed marked superiority in vivo, leading to enhanced specific humoral and cellular immune responses against the SARS-CoV-2 Delta variant RBD antigen. Specifically, vaccines incorporating TMSB10 UTR induced significantly higher levels of specific IgG antibodies and promoted a robust T-cell immune response, characterized by the increased secretion of IFN-γ and IL-4 and the proliferation of CD4+ and CD8+ T cells. These findings underscore the potential of TMSB10 UTR as a strategic component in mRNA vaccine design, offering a promising avenue to bolster vaccine-induced immunity against SARS-CoV-2 and, potentially, other pathogens.

Effect of Mixed Probiotics on Ovalbumin-Induced Atopic Dermatitis in Juvenile Mice

Atopic dermatitis is one of the most common dermatologic problems, especially in children. Given the ability of symbiotic microorganisms in modulating the immune system, probiotics administration has been studied in previous research in the management of atopic dermatitis. However, there are conflicting results between studies. In this study, we aimed to assess the effectiveness of mixed probiotics as a treatment option for atopic dermatitis induced by ovalbumin. BALB/c juvenile mice were classified and divided into the ovalbumin group, mixed probiotic group (ovalbumin + LK), and control group. Except for the control group, all mice were sensitized with ovalbumin to establish a model of atopic dermatitis. The mixed probiotics were given by gavage for 14 days. Mice body weight, skin lesions, skin inflammation, ovalbumin-specific Ig, the number of Treg and CD103+DC, and the expression level of PD-1/PD-L1 were examined. The results showed that mixed probiotics can improve body weight and alleviate skin symptoms. Mixed probiotics reduced serum Th2 inflammatory factors, eosinophils, mast cell degranulation, mast cell count, and the expression of ovalbumin-specific immunoglobulin E/G1 and increased the anti-inflammatory cytokine interleukin-10, Treg cells, CD103+DC cells, and the expression level of PD-1/PD-L1. These findings suggest that mixed probiotics could be a viable treatment option for atopic dermatitis and provide insight into the underlying mechanisms involved.

Microbiota substances modulate dendritic cells activity: A critical view

Contemporary research in the field of microbiota shows that commensal bacteria influence physiological activity of different organs and systems of a human organism, such as brain, lungs, immune and metabolic systems. This influence is realized by various processes. One of them is trough modulation of immune mechanisms. Interactions between microbiota and the human immune system are known to be complex and ambiguous. Dendritic cells (DCs) are unique cells, which initiate the development and polarization of adaptive immune response. These cells also interconnect native and specific immune reactivity. A large set of biochemical signals from microbiota in the form of different microbiota associated molecular patterns (MAMPs) and bacterial metabolites that act locally and distantly in the human organism. As a result, commensal bacteria influence the maturity and activity of dendritic cells and affect the overall immune reactivity of the human organism. It then determines the response to pathogenic microorganisms, inflammation, associated with different pathological conditions and even affects the effectiveness of vaccination.

Role of autoreactive Tc17 cells in the pathogenesis of experimental autoimmune encephalomyelitis

Background

The pathogenesis of multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE—an animal model of MS) is primarily mediated by T cells. However, recent studies have only focused on interleukin (IL)‐17‐secreting CD4+ T‐helper cells, also known as Th17 cells. This study aimed to compare Th17 cells and IL‐17‐secreting CD8+ T‐cytotoxic cells (Tc17) in the context of MS/EAE.

Methods

Female C57BL/6 mice were immunized with myelin oligodendrocyte glycoprotein peptides 35–55 (MOG35–55), pertussis toxin, and complete Freund's adjuvant to establish the EAE animal model. T cells were isolated from the spleen (12–14 days postimmunization). CD4+ and CD8+ T cells were purified using isolation kit and then differentiated into Th17 and Tc17, respectively, using MOG35–55 and IL‐23. The secretion levels of interferon‐γ (IFN‐γ) and IL‐17 were measured via enzyme‐linked immunosorbent assay using cultured CD4+ and CD8+ T cell supernatants. The pathogenicity of Tc17 and Th17 cells was assessed through adoptive transfer (tEAE), with the clinical course assessed using an EAE score (0–5). Hematoxylin and eosin as well as Luxol fast blue staining were used to examine the spinal cord. Purified CD8+ CD3+ and CD4+ CD3+ cells differentiated into Tc17 and Th17 cells, respectively, were stimulated with MOG35–55 peptide for proliferation assays.

Results

The results showed that Tc17 cells (15,951 ± 1985 vs. 55,709 ± 4196 cpm; p < 0.050) exhibited a weaker response to highest dose (20 μg/mL) MOG35–55 than Th17 cells. However, this response was not dependent on Th17 cells. After the 48 h stimulation, at the highest dose (20 μg/mL) of MOG35–55. Tc17 cells secreted lower levels of IFN‐γ (280.00 ± 15.00 vs. 556.67 ± 15.28 pg/mL, p < 0.050) and IL‐17 (102.67 ± 5.86 pg/mL vs. 288.33 ± 12.58 pg/mL; p < 0.050) than Th17 cells. Similar patterns were observed for IFN‐γ secretion at 96 and 144 h. Furthermore, Tc17 cell‐induced tEAE mice exhibited similar EAE scores to Th17 cell‐induced tEAE mice and also showed similar inflammation and demyelination.

Conclusion

The degree of pathogenicity of Tc17 cells in EAE is lower than that of Th17 cells. Future investigation on different immune cells and EAE models is warranted to determine the mechanisms underlying MS.

A Simple and Rapid Protocol for the Isolation of Murine Bone Marrow Suitable for the Differentiation of Dendritic Cells

The generation of bone-marrow-derived dendritic cells is a widely used approach in immunological research to study antigen processing and presentation, as well as T-cell activation responses. However, the initial step of isolating the bone marrow can be time-consuming, especially when larger numbers of precursor cells are required. Here, we assessed whether an accelerated bone marrow isolation method using centrifugation is suitable for the differentiation of FMS-like tyrosine kinase 3 ligand-driven dendritic cells. Compared to the conventional flushing method, the centrifugation-based isolation method resulted in a similar bone marrow cell yield on Day 0, increased cell numbers by Day 8, similar proportions of dendritic cell subsets, and consequently a higher number of type 1 conventional dendritic cells (cDC1) from the culture. Although the primary purpose of this method of optimization was to improve experimental efficiency and increase the output of cDC1s, the protocol is also compatible with the differentiation of other dendritic cell subsets such as cDC2 and plasmacytoid dendritic cells, with an improved output cell count and a consistent phenotype.

Role of immune cells in the pathogenesis of myocarditis

Myocarditis is an inflammatory heart disease that mostly affects young people. Myocarditis involves a complex immune network; however, its detailed pathogenesis is currently unclear. The diversity and plasticity of immune cells, either in the peripheral blood or in the heart, have been partially revealed in a number of previous studies involving patients and several kinds of animal models with myocarditis. It is the complexity of immune cells, rather than one cell type that is the culprit. Thus, recognizing the individual intricacies within immune cells in the context of myocarditis pathogenesis and finding the key intersection of the immune network may help in the diagnosis and treatment of this condition. With the vast amount of cell data gained on myocarditis and the recent application of single-cell sequencing, we summarize the multiple functions of currently recognized key immune cells in the pathogenesis of myocarditis to provide an immune background for subsequent investigations.

A narrative review on inflammaging and late-onset hypogonadism

The increasing life expectancy observed in recent years has resulted in a higher prevalence of late-onset hypogonadism (LOH) in older men. LOH is characterized by the decline in testosterone levels and can have significant impacts on physical and mental health. While the underlying causes of LOH are not fully understood, there is a growing interest in exploring the role of inflammaging in its development. Inflammaging is a concept that describes the chronic, low-grade, systemic inflammation that occurs as a result of aging. This inflammatory state has been implicated in the development of various age-related diseases. Several cellular and molecular mechanisms have been identified as contributors to inflammaging, including immune senescence, cellular senescence, autophagy defects, and mitochondrial dysfunction. Despite the extensive research on inflammaging, its relationship with LOH has not yet been thoroughly reviewed in the literature. To address this gap, we aim to review the latest findings related to inflammaging and its impact on the development of LOH. Additionally, we will explore interventions that target inflammaging as potential treatments for LOH.

Topical drug delivery strategies for enhancing drug effectiveness by skin barriers, drug delivery systems and individualized dosing

Topical drug delivery is widely used in various diseases because of the advantages of not passing through the gastrointestinal tract, avoiding gastrointestinal irritation and hepatic first-pass effect, and reaching the lesion directly to reduce unnecessary adverse reactions. The skin helps the organism to defend itself against a huge majority of external aggressions and is one of the most important lines of defense of the body. However, the skin's strong barrier ability is also a huge obstacle to the effectiveness of topical medications. Allowing the bioactive, composition in a drug to pass through the stratum corneum barrier as needed to reach the target site is the most essential need for the bioactive, composition to exert its therapeutic effect. The state of the skin barrier, the choice of delivery system for the bioactive, composition, and individualized disease detection and dosing planning influence the effectiveness of topical medications. Nowadays, enhancing transdermal absorption of topically applied drugs is the hottest research area. However, enhancing transdermal absorption of drugs is not the first choice to improve the effectiveness of all drugs. Excessive transdermal absorption enhances topical drug accumulation at non-target sites and the occurrence of adverse reactions. This paper introduces topical drug delivery strategies to improve drug effectiveness from three perspectives: skin barrier, drug delivery system and individualized drug delivery, describes the current status and shortcomings of topical drug research, and provides new directions and ideas for topical drug research.

The research status and prospects of MUC1 in immunology

In immune processes, molecular - molecular interactions are complex. As MUC1 often appears to be an important molecule in inflammation and tumor immunity, it is necessary to summarize the leading countries, authors, journals, and the cooperation among these entities and, most importantly, to determine the main research directions related to MUC1 in this field and the associated research frontiers. A total of 3,397 related studies published from 2012-2021 were retrieved from the Web of Science core database. The search strategy is TS= (MUC1 OR Mucin-1) refined by WEB OF SCIENCE CATEGORY (IMMUNOLOGY) AND [excluding] PUBLICATION YEARS: (2022) AND DOCUMENT TYPES: (ARTICLE OR REVIEW) AND LANGUAGES: (ENGLISH) AND WEB OF SCIENCE INDEX: (Web of Science Core Collection. SCI), with a timespan of 2012 to 2021. Documented bibliometric visual analysis was performed by CiteSpace and VOSviewer. The number of studies has increased every year. There are 1,982 articles and 1,415 reviews from 89 countries and regions, 3,722 organizations, 1,042 journals, and 17,948 authors. The United States, China, and Germany are the major countries producing publications on this issue. The most published author is Finn OJ and the most influential author is June CH. The key words "chimeric antigen receptor" and "T-cell" highlight the current hot spots and future trends in this field. Research on MUC1 in the field of immunology is still evolving. Through the bibliometric analysis of the existing publications, the current research hotspots and future development trends in this field can be obtained.

Efficient Colon Cancer Immunogene Therapy Through Co-Delivery of IL-22BP mRNA and Tumor Cell Lysate by CLSV Nanoparticles

Background

Messenger ribonucleic acid (mRNA)-based gene therapy has great potential in cancer treatment. However, the application of mRNA-based cancer treatment could be further developed. Elevated delivery ability and enhanced immune response are advantages for expanding the application of mRNA-based cancer therapy. It is crucial that the prepared carrier can cause an immune reaction based on the efficient delivery of mRNA.

Methods

We reported DMP nanoparticle previously, which was obtained by the self-assembly of 1,2-dioleoyl-3-trimethylammonium propane (DOTAP) and (ethylene glycol)-b-poly (ε-caprolactone) (mPEG-PCL). Research demonstrated that DMP can deliver mRNA, siRNA, and plasmid. And it is applied to various tumor types. In our work, the tumor cell lysate was introduced to the internal DMP chain, fusing cell-penetrating peptides (CPPs) modification on the surface forming the CLSV system. And then mixed encoded IL-22BP (interleukin-22 binding protein) mRNA and CLSV to form CLSV/IL-22BP complex.

Results

The size of the CLSV system was 213.2 nm, and the potential was 45.7 mV. The transfection efficiency of the CLSV system is up to 76.45% in C26 cells via the micropinocytosis pathway. The CLSV system also could induce an immune response and significantly elevate the expression of CD80, CD86, and MHC-II in vivo. Then, by binding with IL-22BP (Interleukin-22 binding protein) mRNA, the CLSV/IL-22BP complex inhibited tumor cell growth, with an inhibition rate of up to 82.3% in vitro. The CLSV/IL-22BP complex also inhibited tumor growth in vivo, the tumor cell growth inhibition up to 75.0% in the subcutaneous tumor model, and 84.9% in the abdominal cavity metastasis tumor model.

Conclusion

Our work demonstrates that the CLSV system represents a potent potential for mRNA delivery.

Distinct Immunophenotypic Features in Patients Affected by 22q11.2 Deletion Syndrome with Immune Dysregulation and Infectious Phenotype

The clinical expression of 22q11.2 deletion syndrome (22q11.2 DS) is extremely variable, as patients can present with recurrent or severe infections, immune dysregulation, atopic diseases, or extra-immunological manifestations. The immunological background underlying the different disease manifestations is not completely elucidated. The aim of this study was to identify the immunophenotypic peculiarities of 22q11.2 DS patients presenting with different disease expressions. This study included 34 patients with 22q11.2 DS, divided into three groups according to the clinical phenotype: isolated extra-immunological manifestations (G1), infectious phenotype with increased/severe infections (G2), and immune dysregulation (G3). The patients underwent extended immunophenotyping of the T and B lymphocytes and analysis of the circulating dendritic cells (DCs). In patients with an infectious phenotype, a significant reduction in CD3+ and CD4+ cells and an expansion of CD8 naïve cells was evidenced. On the other hand, the immunophenotype of the patients with immune dysregulation showed a skewing toward memory T cell populations, and reduced levels of recent thymic emigrants (RTEs), while the highest levels of RTEs were detected in the patients with isolated extra-immunological manifestations. This study integrates the current literature, contributing to elucidating the variability in the immune status of patients with 22q11.2DS with different phenotypic expressions, particularly in those with infectious phenotype and immune dysregulation.

Straight to the point: targeted mRNA-delivery to immune cells for improved vaccine design

With the deepening of our understanding of adaptive immunity at the cellular and molecular level, targeting antigens directly to immune cells has proven to be a successful strategy to develop innovative and potent vaccines. Indeed, it offers the potential to increase vaccine potency and/or modulate immune response quality while reducing off-target effects. With mRNA-vaccines establishing themselves as a versatile technology for future applications, in the last years several approaches have been explored to target nanoparticles-enabled mRNA-delivery systems to immune cells, with a focus on dendritic cells. Dendritic cells (DCs) are the most potent antigen presenting cells and key mediators of B- and T-cell immunity, and therefore considered as an ideal target for cell-specific antigen delivery. Indeed, improved potency of DC-targeted vaccines has been proved in vitro and in vivo. This review discusses the potential specific targets for immune system-directed mRNA delivery, as well as the different targeting ligand classes and delivery systems used for this purpose.

Unlocking Dendritic Cell-Based Vaccine Efficacy through Genetic Modulation-How Soon Is Now?

The dendritic cell (DC) vaccine anti-cancer strategy involves tumour-associated antigen loading and maturation of autologous ex vivo cultured DCs, followed by infusion into the cancer patient. This strategy stemmed from the idea that to induce a robust anti-tumour immune response, it was necessary to bypass the fundamental immunosuppressive mechanisms of the tumour microenvironment that dampen down endogenous innate immune cell activation and enable tumours to evade immune attack. Even though the feasibility and safety of DC vaccines have long been confirmed, clinical response rates remain disappointing. Hence, the full potential of DC vaccines has yet to be reached. Whether this cellular-based vaccination approach will fully realise its position in the immunotherapy arsenal is yet to be determined. Attempts to increase DC vaccine immunogenicity will depend on increasing our understanding of DC biology and the signalling pathways involved in antigen uptake, maturation, migration, and T lymphocyte priming to identify amenable molecular targets to improve DC vaccine performance. This review evaluates various genetic engineering strategies that have been employed to optimise and boost the efficacy of DC vaccines.

Guidelines for mouse and human DC generation

This article is part of the Dendritic Cell Guidelines article series, which provides a collection of state-of-the-art protocols for the preparation, phenotype analysis by flow cytometry, generation, fluorescence microscopy, and functional characterization of mouse and human dendritic cells (DC) from lymphoid organs and various non-lymphoid tissues. This article provides protocols with top ticks and pitfalls for preparation and successful generation of mouse and human DC from different cellular sources, such as murine BM and HoxB8 cells, as well as human CD34+ cells from cord blood, BM, and peripheral blood or peripheral blood monocytes. We describe murine cDC1, cDC2, and pDC generation with Flt3L and the generation of BM-derived DC with GM-CSF. Protocols for human DC generation focus on CD34+ cell culture on OP9 cell layers for cDC1, cDC2, cDC3, and pDC subset generation and DC generation from peripheral blood monocytes (MoDC). Additional protocols include enrichment of murine DC subsets, CRISPR/Cas9 editing, and clinical grade human DC generation. While all protocols were written by experienced scientists who routinely use them in their work, this article was also peer-reviewed by leading experts and approved by all co-authors, making it an essential resource for basic and clinical DC immunologists.

Targeting the dendritic cell-T cell axis to develop effective immunotherapies for glioblastoma

Glioblastoma is an aggressive primary brain tumor that has seen few advances in treatments for over 20 years. In response to this desperate clinical need, multiple immunotherapy strategies are under development, including CAR-T cells, immune checkpoint inhibitors, oncolytic viruses and dendritic cell vaccines, although these approaches are yet to yield significant clinical benefit. Potential reasons for the lack of success so far include the immunosuppressive tumor microenvironment, the blood-brain barrier, and systemic changes to the immune system driven by both the tumor and its treatment. Furthermore, while T cells are essential effector cells for tumor control, dendritic cells play an equally important role in T cell activation, and emerging evidence suggests the dendritic cell compartment may be deeply compromised in glioblastoma patients. In this review, we describe the immunotherapy approaches currently under development for glioblastoma and the challenges faced, with a particular emphasis on the critical role of the dendritic cell-T cell axis. We suggest a number of strategies that could be used to boost dendritic cell number and function and propose that the use of these in combination with T cell-targeting strategies could lead to successful tumor control.

High LYRM4-AS1 predicts poor prognosis in patients with glioma and correlates with immune infiltration

Background

Many researches proved that non-coding RNAs are important in glioma development. We screened the differentially expressed genes through The Cancer Genome Atlas (TCGA) database and identified the molecule LYRM4-AS1 associated with prognosis. As a lncRNA, the expression level and role of LYRM4-AS1 in glioma are inconclusive. Therefore, we attempted to assess the clinical significance, expression and related mechanisms of LYRM4-AS1 in glioma by employing cell experiments and an integrative in silico methodology.

Methods

RNA-seq data were obtained from UCSC XENA and TCGA datasets. The Gene Expression Omnibus (GEO) database was used to download glioma-related expression profile data. The LYRM4-AS1 expression level was evaluated. Survival curves were constructed by the Kaplan-Meier method. Cox regression analysis was used to analyze independent variables. Patients were divided into high and low expression group base on the median LYRM4-AS1 expression value in glioma tissues. The DESeq2 R package was used to identify differentially expressed genes (DEGs) between two different expression LYRM4-AS1 groups. Gene set enrichment analysis (GSEA) was conducted. Next, the single-sample Gene Set Enrichment Analysis (ssGSEA) was done to quantify the immune infiltration of immune cells in glioma tissues. Gene expression profiles for glioma tumor tissues were used to quantify the relative enrichment score for each immune cell. Spearman correlation analysis was used to analyze the correlation between LYRM4-AS1 and biomarkers of immune cells as well as immune checkpoints in glioma. Finally, assays for cell apoptosis, cell viability and wound healing were conducted to evaluate the function on U87 MG and U251 cells after knocking down LYRM4-AS1.

Results

We found that LYRM4-AS1 was upregulated and related to the grade and malignancy of glioma. Survival analyses showed that high expression LYRM4-AS1 patients had poor clinical outcomes (P < 0.01). Cox regression analyses demonstrated that LYRM4-AS1 was an independent risk factor for overall survival (OS) in glioma (HR: 274 1.836; CI [1.278-2.639]; P = 0.001). Enrichment and immune infiltration analysis showed interferon signaling and cytokine-cytokine receptor interaction enriched in the LYRM4-AS1 high-expression phenotype, and LYRM4-AS1 showed significantly positively related to immune infiltration as well as immune checkpoints (P < 0.01). The knockdown of LYRM4-AS1 in U87 MG and U251 cells can inhibit migration and proliferation of cells (P < 0.05).

Conclusions

These findings indicated that the increased LYRM4-AS1 may be useful for the diagnosis and prognosis of glioma and might participate in the immune infiltration.

DC vaccine enhances CAR-T cell antitumor activity by overcoming T cell exhaustion and promoting T cell infiltration in solid tumors

OBJECTIVE

Great success has been achieved in CAR-T cell immunotherapy in the treatment of hematological tumors. However, it is particularly difficult in solid tumors, because CAR-T is difficult to enter interior and exert long-term stable immune effects. Dendritic cells (DCs) can not only present tumor antigens but also promote the infiltration of T cells. Therefore, CAR-T cells with the help of DC vaccines are a reliable approach to treat solid tumors.

METHODS

To test whether DC vaccine could promote CAR-T cell therapy in solid tumors, DC vaccine was co-cultured with MSLN CAR-T cells. The in vitro effects of DC vaccine on CAR-T were assessed by measuring cell proliferation, cell differentiation, and cytokine secretion. Effects of DC vaccine on CAR-T were evaluated using mice with subcutaneous tumors in vivo. The infiltration of CAR-T was analyzed using immunofluorescence. The persistence of CAR-T in mouse blood was analyzed using real-time quantitative PCR.

RESULTS

The results showed that DC vaccine significantly enhanced the proliferation potential of MSLN CAR-T cells in vitro. DC vaccines not only promoted the infiltration of CAR-T cells, but also significantly improved the persistence of CAR-T in solid tumors in vivo.

CONCLUSION

In conclusion, this study has demonstrated that DC vaccine can promote CAR-T therapy in solid tumors, which provides the possibility of widespread clinical application of CAR-T cells in the future.

Cannabinoid receptor 2 alleviates sepsis-associated acute lung injury by modulating maturation of dendritic cells

BACKGROUND

Dendritic cells (DCs) play a key role in a variety of inflammatory lung diseases, but their role in sepsis-associated acute lung injury (SA-ALI) is currently not been illuminated. Cannabinoid receptor 2 (CNR2) has been reported to regulate the DCs maturation. However, whether the CNR2 in DCs contributes to therapeutic therapy for SA-ALI remain unclear. In current study, the role of CNR2 on DCs maturation and inflammatory during SA-ALI is to explored.

METHODS

First, the CNR2 level was analyzed in isolated Peripheral Blood Mononuclear Cells (PBMCs) and Bronchoalveolar Lavage Fluid (BALF) from patient with SA-ALI by qRT-PCR and flow cytometry. Subsequently, HU308, a specific agonist of CNR2, and SR144528, a specific antagonist of CNR2, were introduced to explore the function of CNR2 on DCs maturation and inflammatory during SA-ALI. Finally, CNR2 conditional knockout mice were generated to further confirm the function of DCs maturation and Inflammation during SA-ALI.

RESULTS

First, we found that the expression of CNR2 on DCs was decreased in patient with SA-ALI. Besides, the result showed HU308 could decrease the maturation of DCs and the level of inflammatory cytokines, simultaneously reduce pulmonary pathological injury after LPS-induced sepsis in mice. In contrast of HU308, SR144528 exhibits opposite function of DCs maturate, inflammatory cytokines and lung pathological injury. Furthermore, comparing with SR144528 treatment, similar results were obtained in DCs specific CNR2 knockout mice after LPS treatment.

CONCLUSION

CNR2 could alleviate SA-ALI by modulating maturation of DCs and inflammatory factors levels. Targeting CNR2 signaling specifically in DCs has therapeutic potential for the treatment of SA-ALI.

Significant improvement of systemic lupus erythematosus manifestation in children after autologous dendritic cell transfer: a case report and review of literature

Dendritic cells (DC) are postulated to play a role in autoimmune diseases such as Systemic Lupus Erythematosus (SLE). We reported a 13-year-old female SLE patient who presents with chronic arthritis accompanied by persistent fever, dyspnea, sleep disturbance, headache, stomatitis, rash, and muscle weakness. The supporting examinations showed abnormal blood cell counts, positive antinuclear antibody profile, serositis, and neuropathy. Immunosuppressants failed to improve the condition. DC-based vaccine derived from autologous peripheral blood which was introduced with SARS-CoV-2 protein was given to this patient. There was a significant improvement in clinical and laboratory findings. Thus, DC immunotherapy appears to be a potential novel therapy for SLE that needs to be studied.

Current perspective on biological properties of plasmacytoid dendritic cells and dysfunction in gut

Plasmacytoid dendritic cells (pDCs), a subtype of DC, possess unique developmental, morphological, and functional traits that have sparked much debate over the years whether they should be categorized as DCs. The digestive system has the greatest mucosal tissue overall, and the pDC therein is responsible for shaping the adaptive and innate immunity of the gastrointestinal tract, resisting pathogen invasion through generating type I interferons, presenting antigens, and participating in immunological responses. Therefore, its alleged importance in the gut has received a lot of attention in recent years, and a fresh functional overview is still required. Here, we summarize the current understanding of mouse and human pDCs, ranging from their formation and different qualities compared with related cell types to their functional characteristics in intestinal disorders, including colon cancer, infections, autoimmune diseases, and intestinal graft-versus-host disease. The purpose of this review is to convey our insights, demonstrate the limits of existing research, and lay a theoretical foundation for the rational development and use of pDCs in future clinical practice.

Endoplasmic Reticulum Stress in Systemic Lupus Erythematosus and Lupus Nephritis: Potential Therapeutic Target

Systemic lupus erythematosus (SLE) is a complex autoimmune disease. Approximately one-third to two-thirds of the patients with SLE progress to lupus nephritis (LN). The pathogenesis of SLE and LN has not yet been fully elucidated, and effective treatment for both conditions is lacking. The endoplasmic reticulum (ER) is the largest intracellular organelle and is a site of protein synthesis, lipid metabolism, and calcium storage. Under stress, the function of ER is disrupted, and the accumulation of unfolded or misfolded proteins occurs in ER, resulting in an ER stress (ERS) response. ERS is involved in the dysfunction of B cells, macrophages, T cells, dendritic cells, neutrophils, and other immune cells, causing immune system disorders, such as SLE. In addition, ERS is also involved in renal resident cell injury and contributes to the progression of LN. The molecular chaperones, autophagy, and proteasome degradation pathways inhibit ERS and restore ER homeostasis to improve the dysfunction of immune cells and renal resident cell injury. This may be a therapeutic strategy for SLE and LN. In this review, we summarize advances in this field.

Cell-targeted vaccines: implications for adaptive immunity

Recent advancements in immunology and chemistry have facilitated advancements in targeted vaccine technology. Targeting specific cell types, tissue locations, or receptors can allow for modulation of the adaptive immune response to vaccines. This review provides an overview of cellular targets of vaccines, suggests methods of targeting and downstream effects on immune responses, and summarizes general trends in the literature. Understanding the relationships between vaccine targets and subsequent adaptive immune responses is critical for effective vaccine design. This knowledge could facilitate design of more effective, disease-specialized vaccines.

Saponin-based adjuvants enhance antigen cross-presentation in human CD11c+ CD1c+ CD5- CD163+ conventional type 2 dendritic cells

BACKGROUND

Adjuvants are key for effective vaccination against cancer and chronic infectious diseases. Saponin-based adjuvants (SBAs) are unique among adjuvants in their ability to induce robust cell-mediated immune responses in addition to antibody responses. Recent preclinical studies revealed that SBAs induced cross-presentation and lipid bodies in otherwise poorly cross-presenting CD11b+ murine dendritic cells (DCs).

METHOD

Here, we investigated the response of human DC subsets to SBAs with RNA sequencing and pathway analyses, lipid body induction visualized by laser scanning microscopy, antigen translocation to the cytosol, and antigen cross-presentation to CD8+ T cells.

RESULTS

RNA sequencing of SBA-treated conventional type 1 DC (cDC1) and type 2 DC (cDC2) subsets uncovered that SBAs upregulated lipid-related pathways in CD11c+ CD1c+ cDC2s, especially in the CD5- CD163+ CD14+ cDC2 subset. Moreover, SBAs induced lipid bodies and enhanced endosomal antigen translocation into the cytosol in this particular cDC2 subset. Finally, SBAs enhanced cross-presentation only in cDC2s, which requires the CD163+ CD14+ cDC2 subset.

CONCLUSIONS

These data thus identify the CD163+ CD14+ cDC2 subset as the main SBA-responsive DC subset in humans and imply new strategies to optimize the application of saponin-based adjuvants in a potent cancer vaccine.

Targeting dendritic cells to advance cross-presentation and vaccination outcomes

Dendritic cells (DCs) are a complex network of specialised antigen-presenting cells that are critical initiators of adaptive immunity. Targeting antigen directly to DCs in situ is a vaccination strategy that selectively delivers antigen to receptors expressed by DC subtypes. This approach exploits specific DC subset functions of antigen uptake and presentation. Here, we review DC-targeted vaccination strategies that are designed to elicit effective cross-presentation for CD8+ T cell immunity. In particular, we focus on approaches that exploit receptors highly expressed by mouse and human cDCs equipped with superior cross-presentation capacity. These receptors include DEC205, Clec9A and XCR1. Targeting DC receptors Clec12A, Clec4A4 and mannose receptor is also reviewed. Outcomes of DC-targeted vaccination in mouse models through to human clinical trials is discussed. This is a promising new vaccination approach capable of directly targeting the cross-presentation pathway for prevention and treatment of tumours and infectious diseases.

Immunoregulatory effects of Huaier (Trametes robiniophila Murr) and relevant clinical applications

Huaier (Trametes robiniophila Murr) is a medicinal fungus of traditional Chinese medicine with more than 1000 years of history of clinical application. Its remarkable anticancer activities has led to its application in treating diverse malignancies. In recent years, the immunomodulatory effects of Huaier have been uncovered and proved to be beneficial in a plethora of immune-related diseases including cancer, nephropathy, asthma, etc. In this review, we comprehensively summarized the active components of Huaier, its regulatory activities on multifaceted aspects of the immune system, its application in various clinical settings as well as toxicologic evidence. Based on currently available literature, Huaier possesses broad-spectrum regulatory activities on various components of the innate and adaptive immune system, including macrophages, dendritic cells, natural killer cells, T and B lymphocytes, etc. Versatile immunologic reactions are under the regulation of Huaier from expression of damage-associated molecular patterns, immune cell activation and maturation to cell proliferation, differentiation, antibody production, expression of cytokines and chemokines and terminal intracellular signal transduction. Moreover, some modulatory activities of Huaier might be context-dependent, typically promoting the restoration toward normal physiological status. With excellent efficacy and minimal side effects, we foresee more extensive application of Huaier for treating immune-related disorders.

Facing the Challenges in the COVID-19 Pandemic Era: From Standard Treatments to the Umbilical Cord-Derived Mesenchymal Stromal Cells as a New Therapeutic Strategy

Coronavirus disease 2019 (COVID-19), the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which counts more than 650 million cases and more than 6.6 million of deaths worldwide, affects the respiratory system with typical symptoms such as fever, cough, sore throat, acute respiratory distress syndrome (ARDS), and fatigue. Other nonpulmonary manifestations are related with abnormal inflammatory response, the "cytokine storm", that could lead to a multiorgan disease and to death. Evolution of effective vaccines against SARS-CoV-2 provided multiple options to prevent the infection, but the treatment of the severe forms remains difficult to manage. The cytokine storm is usually counteracted with standard medical care and anti-inflammatory drugs, but researchers moved forward their studies on new strategies based on cell therapy approaches. The perinatal tissues, such as placental membranes, amniotic fluid, and umbilical cord derivatives, are enriched in mesenchymal stromal cells (MSCs) that exert a well-known anti-inflammatory role, immune response modulation, and tissue repair. In this review, we focused on umbilical-cord-derived MSCs (UC-MSCs) used in in vitro and in vivo studies in order to evaluate the weakening of the severe symptoms, and on recent clinical trials from different databases, supporting the favorable potential of UC-MSCs as therapeutic strategy.

Evaluation of immunogenicity of gene-deleted and subunit vaccines constructed against the emerging pseudorabies virus variants

BACKGROUND

Pseudorabies (PR) (also called Aujeszky's disease, AD) is a serious infectious disease affecting pigs and other animals worldwide. The emergence of variant strains of pseudorabies virus (PRV) since 2011 has led to PR outbreaks in China and a vaccine that antigenically more closely matches these PRV variants could represent an added value to control these infections.

METHODS

The objective of this study was to develop new live attenuated and subunit vaccines against PRV variant strains. Genomic alterations of vaccine strains were based on the highly virulent SD-2017 mutant strain and gene-deleted strains SD-2017ΔgE/gI and SD-2017ΔgE/gI/TK, which constructed using homologous recombination technology. PRV gB-DCpep (Dendritic cells targeting peptide) and PorB (the outer membrane pore proteins of N. meningitidis) proteins containing gp67 protein secretion signal peptide were expressed using the baculovirus system for the preparation of subunit vaccines. We used experimental animal rabbits to test immunogenicity to evaluate the effect of the newly constructed PR vaccines.

RESULTS

Compared with the PRV-gB subunit vaccine and SD-2017ΔgE/gI inactivated vaccines, rabbits (n = 10) that were intramuscularly vaccinated with SD-2017ΔgE/gI/TK live attenuated vaccine and PRV-gB + PorB subunit vaccine showed significantly higher anti-PRV-specific antibodies as well as neutralizing antibodies and IFN-γ levels in serum. In addition, the SD-2017ΔgE/gI/TK live attenuated vaccine and PRV-gB + PorB subunit vaccine protected (90-100%) rabbits against homologous infection by the PRV variant strain. No obvious pathological damage was observed in these vaccinated rabbits.

CONCLUSIONS

The SD-2017ΔgE/gI/TK live attenuated vaccine provided 100% protection against PRV variant challenge. Interestingly, the subunit vaccines with gB protein linked to DCpep and PorB protein as adjuvant may also be a promising and effective PRV variant vaccine candidate.