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Cancers Jun 2024Among professional antigen-presenting cells, dendritic cells (DCs) orchestrate innate and adaptive immunity and play a pivotal role in anti-tumor immunity. DCs are a... (Review)
Review
Among professional antigen-presenting cells, dendritic cells (DCs) orchestrate innate and adaptive immunity and play a pivotal role in anti-tumor immunity. DCs are a heterogeneous population with varying functions in the tumor microenvironment (TME). Tumor-associated DCs differentiate developmentally and functionally into three main subsets: conventional DCs (cDCs), plasmacytoid DCs (pDCs), and monocyte-derived DCs (MoDCs). There are two major subsets of cDCs in TME, cDC1 and cDC2. cDC1 is critical for cross-presenting tumor antigens to activate cytotoxic CD8 T cells and is also required for priming earlier CD4 T cells in certain solid tumors. cDC2 is vital for priming anti-tumor CD4 T cells in multiple tumor models. pDC is a unique subset of DCs and produces type I IFN through TLR7 and TLR9. Studies have shown that pDCs are related to immunosuppression in the TME through the secretion of immunosuppressive cytokines and by promoting regulatory T cells. MoDCs differentiate separately from monocytes in response to inflammatory cues and infection. Also, MoDCs can cross-prime CD8 T cells. In this review, we summarize the subsets and functions of DCs. We also discuss the role of different DC subsets in shaping T cell immunity in TME and targeting DCs for potential immunotherapeutic benefits against cancer.
PubMed: 38927916
DOI: 10.3390/cancers16122211 -
Biomedicines Jun 2024Dendritic cells (DCs) are a heterogeneous group of antigen-presenting cells crucial for fostering allograft tolerance while simultaneously supporting host defense... (Review)
Review
Dendritic cells (DCs) are a heterogeneous group of antigen-presenting cells crucial for fostering allograft tolerance while simultaneously supporting host defense against infections and cancer. Within the tumor microenvironment, DCs can either mount an immune response against cancer cells or foster immunotolerance, presenting a dual role. In immunocompromised individuals, posttransplant malignancies pose a significant health concern, with DCs serving as vital players in immune responses against cancer cells. Both recipient- and donor-derived DCs play a critical role in the rejection process, infiltrating the transplanted organ and sustaining T-cell responses. The use of immunosuppressive drugs represents the predominant approach to control this immunological barrier in transplanted organs. Evidence has shed light on the immunopharmacology of these drugs and novel strategies for manipulating DCs to promote allograft survival. Therefore, comprehending the mechanisms underlying this intricate microenvironment and the effects of immunosuppressive therapy on DCs is crucial for developing targeted therapies to reduce graft failure rates. This review will delve into the fundamental immunobiology of DCs and provide a detailed exploration of their clinical significance concerning alloimmune responses and posttransplant malignancies.
PubMed: 38927447
DOI: 10.3390/biomedicines12061240 -
Biomolecules Jun 2024Plasmacytoid dendritic cells (pDCs) are vital players in antiviral immune responses because of their high levels of IFN-α secretion. However, this attribute has also...
Plasmacytoid dendritic cells (pDCs) are vital players in antiviral immune responses because of their high levels of IFN-α secretion. However, this attribute has also implicated them as critical factors behind the immunopathogenesis of inflammatory diseases, and no currently available therapy can efficiently inhibit pDCs' aberrant activation. Mesenchymal stromal cells (MSCs) possess stromal immunomodulatory functionality, regulating immune cell activation through several mechanisms, including the adenosinergic (CD39/CD73/adenosine) pathway. The IFN-γ preconditioning of bone marrow MSCs improves their inhibitory properties for therapy applications; however, isolating human gingival tissue-derived MSCs (hGMSCs) is more accessible. These cells have shown better immunomodulatory effects, yet the outcome of IFN-γ preconditioning and its impact on the adenosinergic pathway has not been evaluated. This study first validated the immunoregulatory properties of primary-cultured hGMSCs, and the results showed that IFN-γ preconditioning strengthens CD39/CD73 coexpression, adenosine production, and the regulatory properties of hGMSC, which were confirmed by describing for the first time their ability to reduce pDC activation and their IFN-α secretion and to increase the frequency of CD73+ pDC. In addition, when CD73's enzymatic activity was neutralized in hGMSCs, adenosine production and the IFN-γ preconditioning effect were restrained. This evidence might be applied to design hGMSCs- and adenosine-based immunotherapeutic strategies for treating inflammatory disorders that are associated with pDC overactivation.
Topics: Humans; Mesenchymal Stem Cells; Dendritic Cells; Adenosine; Interferon-gamma; Gingiva; 5'-Nucleotidase; Cells, Cultured; Apyrase; GPI-Linked Proteins
PubMed: 38927060
DOI: 10.3390/biom14060658 -
Biomolecules May 2024Acute pancreatitis (AP) is a complex inflammatory condition that can lead to systemic inflammatory responses and multiple organ dysfunction. This study investigates the...
Acute pancreatitis (AP) is a complex inflammatory condition that can lead to systemic inflammatory responses and multiple organ dysfunction. This study investigates the role of Galectin-3 (Gal-3), a β-galactoside-binding lectin, in modulating acquired immune responses in AP. Acute pancreatitis was induced by ligation of the bile-pancreatic duct in wild-type and Galectin-3-deficient C57BL/6 mice. We determined the phenotypic and molecular features of inflammatory cells, serum concentrations of amylase, pancreatic trypsin activity, and pancreatic and lung pathology. Galectin-3 deficiency decreased the total number of CD3CD49 T cells and CD4 T helper cells, downregulated the production of inflammatory cytokine and IFN-γ, and increased the accumulation of IL-10-producing Foxp3 T regulatory cells and regulatory CD4 T cells in the pancreata of diseased animals. The deletion of Galectin-3 ameliorates acute pancreatitis characterized by lowering serum amylase concentration and pancreatic trypsin activity, and attenuating of the histopathology of the lung. These findings shed light on the role of Galectin-3 in acquired immune response in acute pancreatitis and identify Galectin-3 as an attractive target for investigation of the immunopathogenesis of disease and for consideration as a potential therapeutic target for patients with acute inflammatory disease of the pancreas.
Topics: Animals; Pancreatitis; Galectin 3; Mice; T-Lymphocytes, Regulatory; Mice, Inbred C57BL; Mice, Knockout; Acute Disease; Male; Amylases
PubMed: 38927046
DOI: 10.3390/biom14060642 -
Nature Communications Jun 2024Diet composition impacts metabolic health and is now recognized to shape the immune system, especially in the intestinal tract. Nutritional imbalance and increased...
Diet composition impacts metabolic health and is now recognized to shape the immune system, especially in the intestinal tract. Nutritional imbalance and increased caloric intake are induced by high-fat diet (HFD) in which lipids are enriched at the expense of dietary fibers. Such nutritional challenge alters glucose homeostasis as well as intestinal immunity. Here, we observed that short-term HFD induced dysbiosis, glucose intolerance and decreased intestinal RORγt CD4 T cells, including peripherally-induced Tregs and IL17-producing (Th17) T cells. However, supplementation of HFD-fed male mice with the fermentable dietary fiber fructooligosaccharides (FOS) was sufficient to maintain RORγt CD4 T cell subsets and microbial species known to induce them, alongside having a beneficial impact on glucose tolerance. FOS-mediated normalization of Th17 cells and amelioration of glucose handling required the cDC2 dendritic cell subset in HFD-fed animals, while IL-17 neutralization limited FOS impact on glucose tolerance. Overall, we uncover a pivotal role of cDC2 in the control of the immune and metabolic effects of FOS in the context of HFD feeding.
Topics: Animals; Oligosaccharides; Diet, High-Fat; Dendritic Cells; Male; Mice; Homeostasis; Mice, Inbred C57BL; Th17 Cells; Glucose; Interleukin-17; Dietary Fiber; Glucose Intolerance; Nuclear Receptor Subfamily 1, Group F, Member 3; Dysbiosis; Gastrointestinal Microbiome
PubMed: 38926424
DOI: 10.1038/s41467-024-49820-x -
Cell Death Discovery Jun 2024Lymph node metastasis (LNM) facilitates distant tumor colonization and leads to the high mortality in patients with intrahepatic cholangiocarcinoma (ICC). However, it...
Lymph node metastasis (LNM) facilitates distant tumor colonization and leads to the high mortality in patients with intrahepatic cholangiocarcinoma (ICC). However, it remains elusive how ICC cells subvert immune surveillance within the primary tumor immune microenvironment (TIME) and subsequently metastasize to lymph nodes (LNs). In this study, scRNA-seq and bulk RNA-seq analyses identified decreased infiltration of dendritic cells (DCs) into primary tumor sites of ICC with LNM, which was further validated via dual-color immunofluorescence staining of 219 surgically resected ICC samples. Tumor-infiltrating DCs correlated with increased CD8 T cell infiltration and better prognoses in ICC patients. Mechanistically, β-catenin-mediated CXCL12 suppression accounted for the impaired DC recruitment in ICC with LNM. Two mouse ICC cell lines MuCCA1 and mIC-23 cells were established from AKT/NICD or AKT/YAP-induced murine ICCs respectively and were utilized to construct the footpad tumor LNM model. We found that expansion and activation of conventional DCs (cDCs) by combined Flt3L and poly(I:C) (FL-pIC) therapy markedly suppressed the metastasis of mIC-23 cells to popliteal LNs. Moreover, β-catenin inhibition restored the defective DC infiltration into primary tumor sites and reduced the incidence of LNM in ICC. Collectively, our findings identify tumor cell intrinsic β-catenin activation as a key mechanism for subverting DC-mediated anti-tumor immunity in ICC with LNM. FL-pIC therapy or β-catenin inhibitor could merit exploration as a potential regimen for mitigating ICC cell metastasis to LNs and achieving effective tumor immune control.
PubMed: 38926350
DOI: 10.1038/s41420-024-02079-z -
Anticancer immune reaction and lymph node sinus macrophages: a review from human and animal studies.Journal of Clinical and Experimental... 2024Lymph nodes are secondary lymphoid organs localized throughout the body that typically appear as bean-like nodules. Numerous antigen-presenting cells, including... (Review)
Review
Lymph nodes are secondary lymphoid organs localized throughout the body that typically appear as bean-like nodules. Numerous antigen-presenting cells, including dendritic cells and macrophages, that mediate host defense responses against pathogens, such as bacteria and viruses, reside within lymph nodes. To react to cancer cell-derived antigens in a variety of cancers, antigen-presenting cells induce cytotoxic T lymphocytes (CTLs). In relation to anticancer immune responses, macrophages in the lymph node sinus have been of particular interest because a number of studies involving both human specimens and animal models have reported that lymph node macrophages expressing CD169 play a key role in activating anticancer CTLs. Recent studies have indicated that dysfunction of lymph node macrophages potentially contributes to immune suppression in elderly patients and immunological "cold" tumors. Therefore, in anticancer therapy, the regulation of lymph node macrophages is a potentially promising approach.
Topics: Humans; Lymph Nodes; Animals; Macrophages; Neoplasms; Sialic Acid Binding Ig-like Lectin 1; T-Lymphocytes, Cytotoxic
PubMed: 38925976
DOI: 10.3960/jslrt.24017 -
Journal For Immunotherapy of Cancer Jun 2024Despite continuous improvements in the new target and construction of chimeric antigen receptor (CAR)-T, relapse remains a significant challenge following CAR-T therapy....
BACKGROUND
Despite continuous improvements in the new target and construction of chimeric antigen receptor (CAR)-T, relapse remains a significant challenge following CAR-T therapy. Tumor microenvironment (TME) strongly correlates with the efficacy of CAR-T therapy. V-domain Ig suppressor of T-cell activation (VISTA), which exerts a multifaceted and controversial role in regulating the TME, acts not only as a ligand on antigen-presenting cells but also functions as a receptor on T cells. However, the characteristics and underlying mechanisms governing endogenous T-cell activation by VISTA, which are pivotal for reshaping the TME, remain incompletely elucidated.
METHODS
The immunocompetent B acute lymphoblastic leukemia (B-ALL), lymphoma, and melanoma murine models were employed to investigate the characteristics of endogenous T cells within the TME following CD19 and hCAIX CAR-T cell therapy, respectively. Furthermore, we examined the role of VISTA controlled by interferon (IFN)-γ signaling in regulating endogenous T-cell activation and functionality in B-ALL mice.
RESULTS
We demonstrated that the administration of CD19 CAR-T or hCAIX CAR-T cell therapy elicited augmented immune responses of endogenous T cells within the TME of B-ALL, lymphoma, and melanoma mice, thereby substantiating the efficacy of CAR-T cell efficacy. However, in the TME lacking IFN-γ signaling, VISTA levels remained elevated, resulting in attenuated cytotoxicity of endogenous T cells and reduced B-ALL recipient survival. Mice treated with CD19 CAR-T cells exhibited increased proportions of endogenous memory T cells during prolonged remission, which possessed the tumor-responsive capabilities to protect against B-ALL re-challenge. Compared with wild-type (WT) CAR-T treated mice, the administration of IFN-γ CAR-T to both WT and IFN-γ recipients resulted in a reduction in the numbers of endogenous CD4 and CD8 effectors, while exhibiting increased populations of naïve-like CD4 T and memory CD8 T cells. VISTA expression consistently remained elevated in resting or memory CD4 T cells, with distinct localization from programmed cell death protein-1 (PD-1) expressing T subsets. Blocking the VISTA signal enhanced dendritic cell-induced proliferation and cytokine production by syngeneic T cells.
CONCLUSION
Our findings confirm that endogenous T-cell activation and functionality are regulated by VISTA, which is associated with the therapeutic efficiency of CAR-T and provides a promising therapeutic strategy for relapse cases in CAR-T therapy.
Topics: Animals; Mice; Interferon-gamma; Immunotherapy, Adoptive; Antigens, CD19; Tumor Microenvironment; T-Lymphocytes; Humans; Cell Line, Tumor; Disease Models, Animal; B7 Antigens; Lymphocyte Activation; Receptors, Chimeric Antigen; Membrane Proteins
PubMed: 38925679
DOI: 10.1136/jitc-2023-008364 -
PLoS Pathogens Jun 2024AXL+ Siglec-6+ dendritic cells (ASDC) are novel myeloid DCs which can be subdivided into CD11c+ and CD123+ expressing subsets. We showed for the first time that these...
AXL+ Siglec-6+ dendritic cells (ASDC) are novel myeloid DCs which can be subdivided into CD11c+ and CD123+ expressing subsets. We showed for the first time that these two ASDC subsets are present in inflamed human anogenital tissues where HIV transmission occurs. Their presence in inflamed tissues was supported by single cell RNA analysis of public databases of such tissues including psoriasis diseased skin and colorectal cancer. Almost all previous studies have examined ASDCs as a combined population. Our data revealed that the two ASDC subsets differ markedly in their functions when compared with each other and to pDCs. Relative to their cell functions, both subsets of blood ASDCs but not pDCs expressed co-stimulatory and maturation markers which were more prevalent on CD11c+ ASDCs, thus inducing more T cell proliferation and activation than their CD123+ counterparts. There was also a significant polarisation of naïve T cells by both ASDC subsets toward Th2, Th9, Th22, Th17 and Treg but less toward a Th1 phenotype. Furthermore, we investigated the expression of chemokine receptors that facilitate ASDCs and pDCs migration from blood to inflamed tissues, their HIV binding receptors, and their interactions with HIV and CD4 T cells. For HIV infection, within 2 hours of HIV exposure, CD11c+ ASDCs showed a trend in more viral transfer to T cells than CD123+ ASDCs and pDCs for first phase transfer. However, for second phase transfer, CD123+ ASDCs showed a trend in transferring more HIV than CD11c+ ASDCs and there was no viral transfer from pDCs. As anogenital inflammation is a prerequisite for HIV transmission, strategies to inhibit ASDC recruitment into inflamed tissues and their ability to transmit HIV to CD4 T cells should be considered.
PubMed: 38924030
DOI: 10.1371/journal.ppat.1012351 -
Immunity, Inflammation and Disease Jun 2024Major histocompatibility complex (MHC) class II molecules expressed on B cells, monocytes and dendritic cells present processed peptides to CD4 T cells as one of the...
BACKGROUND
Major histocompatibility complex (MHC) class II molecules expressed on B cells, monocytes and dendritic cells present processed peptides to CD4 T cells as one of the mechanisms to combat infection and inflammation.
AIM
To study MHC II expression in a variety of nonhuman primate species, including New World (NWM) squirrel monkeys (Saimiri boliviensis boliviensis), owl monkeys (Aotus nancymae), common marmosets (Callithrix spp.), and Old World (OWM) rhesus (Macaca mulatta), baboons (Papio anubis).
METHODS
Two clones of cross-reactive mouse anti-human HLADR monoclonal antibodies (mAb) binding were analyzed by flow cytometry to evaluate MHC II expression on NHP immune cells, including T lymphocytes in whole blood (WB) and peripheral blood mononuclear cells (PBMC).
RESULTS
MHC class II antibody reactivity is seen with CD20 B cells, CD14 monocytes and CD3 T lymphocytes. Specific reactivity with both clones was demonstrated in T lymphocytes: this reactivity was not inhibited by purified CD16 antibody but was completely inhibited when pre-blocked with purified unconjugated MHC II antibody. Freshly prepared PBMC also showed reactivity with T lymphocytes without any stimulation. Interestingly, peripheral blood from rhesus macaques and olive baboons (OWM) showed no such T lymphocyte associated MHCII antibody reactivity.
DISCUSSION & CONCLUSION
Our results from antibody (MHC II) reactivity clearly show the potential existence of constitutively expressed (with no stimulation) MHC II molecules on T lymphocytes in new world monkeys. These results suggest that additional study is warranted to evaluate the functional and evolutionary significance of these finding and to better understand MHC II expression on T lymphocytes in new world monkeys.
Topics: Animals; Histocompatibility Antigens Class II; HLA-DR Antigens; T-Lymphocytes; Humans; Macaca mulatta; Antibodies, Monoclonal; B-Lymphocytes; Saimiri; Callithrix; Flow Cytometry; Papio anubis; Platyrrhini
PubMed: 38923761
DOI: 10.1002/iid3.1318