Search

Photoimmunotherapy is a promising cancer treatment modality. While potent 1‐e− oxidative species are known to induce immunogenic cell death (ICD), they are also associated with unspecific oxidation and collateral tissue damage. This difficulty may be addressed by post‐generation radical reinforcement. Namely, non‐oxidative radicals are first generated and subsequently activated into powerful oxidative radicals to induce ICD. Here, we developed a photo‐triggered molecular donor (NPCD565) of nitrosoperoxycarbonate (ONOOCO2−), the first of its class to our knowledge, and further evaluated its feasibility for immunotherapy. Upon irradiation of NPCD565 by light within a broad spectral region from ultraviolet to red, ONOOCO2− is released along with a bright rhodamine dye (RD565), whose fluorescence is a reliable and convenient build‐in reporter for the localization, kinetics, and dose of ONOOCO2− generation. Upon photolysis of NPCD565 in 4T1 cells, damage‐associated molecular patterns (DAMPs) indicative of ICD were observed and confirmed to exhibit immunogenicity by induced maturation of dendritic cells. In vivo studies with a bilateral tumor‐bearing mouse model showcased the potent tumor‐killing capability of NPCD565 of the primary tumors and growth suppression of the distant tumors. This work unveils the potent immunogenicity of ONOOCO2−, and its donor (NPCD565) has broad potential for photo‐immunotherapy of cancer. [ABSTRACT FROM AUTHOR]

Photoimmunotherapy is a promising cancer treatment modality. While potent 1‐e− oxidative species are known to induce immunogenic cell death (ICD), they are also associated with unspecific oxidation and collateral tissue damage. This difficulty may be addressed by post‐generation radical reinforcement. Namely, non‐oxidative radicals are first generated and subsequently activated into powerful oxidative radicals to induce ICD. Here, we developed a photo‐triggered molecular donor (NPCD565) of nitrosoperoxycarbonate (ONOOCO2−), the first of its class to our knowledge, and further evaluated its feasibility for immunotherapy. Upon irradiation of NPCD565 by light within a broad spectral region from ultraviolet to red, ONOOCO2− is released along with a bright rhodamine dye (RD565), whose fluorescence is a reliable and convenient build‐in reporter for the localization, kinetics, and dose of ONOOCO2− generation. Upon photolysis of NPCD565 in 4T1 cells, damage‐associated molecular patterns (DAMPs) indicative of ICD were observed and confirmed to exhibit immunogenicity by induced maturation of dendritic cells. In vivo studies with a bilateral tumor‐bearing mouse model showcased the potent tumor‐killing capability of NPCD565 of the primary tumors and growth suppression of the distant tumors. This work unveils the potent immunogenicity of ONOOCO2−, and its donor (NPCD565) has broad potential for photo‐immunotherapy of cancer. [ABSTRACT FROM AUTHOR]

The cancer vaccine is one of the potent cancer immunotherapies based on provoking antigen‐specific adaptive immune responses in patients. Activating host antigen‐presenting cells by delivering antigens and adjuvants is one of the most important requirements to enhance cancer vaccine efficacy. This study proposes an effective cancer vaccine platform based on injectable mesocellular foam (MCF) silica microparticles with a dual role capable of in situ recruitment of host dendritic cells (DCs) and intracellular delivery of antigens to the recruited DCs. Subcutaneously administrated MCF microparticles loaded with chemoattractant to DCs (GM‐CSF), antigenic protein (OVA), and TLR9 agonist (CpG‐ODN) lead to robust DC maturation and high antigen‐specific T cell responses. The cell recruitment, DC activation, and T cell responses of MCF‐based cancer vaccine are significantly higher than injectable mesoporous silica scaffold, of which role is mostly limited to the cell recruiting scaffold. These features of MCF lead to effective inhibition of tumor growth in prophylactic vaccine setting and lung metastatic cancer model, representing MCF enabling cell‐recruiting scaffold formation and intracellular delivery of antigen can be a promising material platform for an enhanced cancer vaccine. [ABSTRACT FROM AUTHOR]

This article discusses a study on a rare and aggressive blood cancer called blastic plasmacytoid dendritic cell neoplasm (BPDCN). The study focuses on a gene called IKZF1, which is important for blood cell development. The researchers identified a novel rearrangement of the IKZF1 gene in a BPDCN patient and investigated its effects on blood stem cells and plasmacytoid dendritic cells. They found that the rearrangement influenced the function and differentiation of these cells. The study provides insights into the underlying mechanisms of BPDCN and potential therapeutic targets. However, further research is needed to fully understand the role of IKZF1 in the disease. [Extracted from the article]

Human immunodeficiency virus type 1 (HIV-1) disease manifestations differ between cisgender women and men, including better control of viral replication during primary infection and less frequent residual HIV-1 replication on antiretroviral therapy (ART) in cisgender women with HIV-1 (WWH). Investigating plasmacytoid dendritic cell (pDC) functions and HIV-1 reservoir sizes in 20 WWH on stable ART, we observed inverse correlations between interferon-α and tumor necrosis factor responses of pDCs to Toll-like receptor 7/8 stimulation and intact/total proviral HIV-1 DNA levels. Additionally, ISG15 mRNA levels in peripheral blood mononuclear cells correlated with cytokine responses of pDCs. These findings demonstrate an association between higher type I interferon responses and lower HIV-1 reservoir sizes in WWH on ART, warranting studies to identify the underlying mechanisms. [ABSTRACT FROM AUTHOR]

In the development of dendritic cell (DC) vaccines, the maturation of DCs is a critical stage. Adjuvants play a pivotal role in the maturation of DCs, with a major concern being to ensure both efficacy and safety. This study introduces an innovative approach that combines high efficacy with safety through the synthesis of micro‐adjuvants grafted with copolymers of 2‐(methacrylamido) glucopyranose (MAG) and methacryloxyethyl trimethyl ammonium chloride (DMC). The utilization of metal‐free surface‐initiated atom transfer radical polymerization enables the production of safe and recyclable adjuvants. These micrometer‐sized adjuvants surpass the optimal size range for cellular endocytosis, enabling the retrieval and reuse of them during the ex vivo maturation process, mitigating potential toxicity concerns associated with the endocytosis of non‐metabolized nanoparticles. Additionally, the adjuvants exhibit a "micro‐ligand‐mediated maturation enhancement" effect for DC maturation. This effect is influenced by the shape of the particle, as evidenced by the distinct promotion effects of rod‐like and spherical micro‐adjuvants with comparable sizes. Furthermore, the porous structure of the adjuvants enables them to function as cargo‐carrying "micro‐shuttles", releasing antigens upon binding to DCs to facilitate efficient antigen delivery. [ABSTRACT FROM AUTHOR]

In the development of dendritic cell (DC) vaccines, the maturation of DCs is a critical stage. Adjuvants play a pivotal role in the maturation of DCs, with a major concern being to ensure both efficacy and safety. This study introduces an innovative approach that combines high efficacy with safety through the synthesis of micro‐adjuvants grafted with copolymers of 2‐(methacrylamido) glucopyranose (MAG) and methacryloxyethyl trimethyl ammonium chloride (DMC). The utilization of metal‐free surface‐initiated atom transfer radical polymerization enables the production of safe and recyclable adjuvants. These micrometer‐sized adjuvants surpass the optimal size range for cellular endocytosis, enabling the retrieval and reuse of them during the ex vivo maturation process, mitigating potential toxicity concerns associated with the endocytosis of non‐metabolized nanoparticles. Additionally, the adjuvants exhibit a "micro‐ligand‐mediated maturation enhancement" effect for DC maturation. This effect is influenced by the shape of the particle, as evidenced by the distinct promotion effects of rod‐like and spherical micro‐adjuvants with comparable sizes. Furthermore, the porous structure of the adjuvants enables them to function as cargo‐carrying "micro‐shuttles", releasing antigens upon binding to DCs to facilitate efficient antigen delivery. [ABSTRACT FROM AUTHOR]

Dendritic cells (DCs) have been intensively studied in correlation to tumor immunology and for the development DC-based cancer vaccines. Here, we present the significance of the temporal aspect of DC maturation for the most essential subsequent timepoint, namely at interaction with responding T cells or after CD40-Ligand restimulation. Mostly, DC maturation is still being achieved by activation processes which lasts 24 h to 48 h. We hypothesized this amount of time is excessive from a biological standpoint and could be the underlying cause for functional exhaustion. Indeed, shorter maturation periods resulted in extensive capacity of monocyte-derived DCs to produce inflammatory cytokines after re-stimulation with CD40-Ligand. This effect was most evident for the primary type 1 polarizing cytokine, IL-12p70. This capacity reached peak at 6 h and dropped sharply with longer exposure to initial maturation stimuli (up to 48 h). The 6 h maturation protocol reflected superiority in subsequent functionality tests. Namely, DCs displayed twice the allostimulatory capacity of 24 h- and 48 h-matured DCs. Similarly, type 1 T cell response measured by IFN-γ production was 3-fold higher when CD4+ T cells had been stimulated with shortly matured DC and over 8-fold greater in case of CD8+ T cells, compared to longer matured DCs. The extent of melanoma-specific CD8+ cytotoxic T cell induction was also greater in case of 6 h DC maturation. The major limitation of the study is that it lacks in vivo evidence, which we aim to examine in the future. Our findings show an unexpectedly significant impact of temporal exposure to activation signals for subsequent DC functionality, which we believe can be readily integrated into existing knowledge on in vitro/ex vivo DC manipulation for various uses. We also believe this has important implications for DC vaccine design for future clinical trials. [ABSTRACT FROM AUTHOR]

Rhabdomyosarcoma (RMS) with TFCP2 rearrangement has been identified recently. This entity has a distinctive clinicopathologic features: a rapidly aggressive clinical course, a preference for the craniofacial bones, a spindle and epithelioid histomorphology, and positive immunohistochemistry for epithelial markers, ALK, and myogenic markers. RMS with TFCP2 rearrangement is rare and may be misdiagnosed as other spindle cell tumors. Here, we report a case of this entity arising in the mandible, which was initially diagnosed as ossifying fibroma in primary tumor in another hospital. A 26-year-old man presented with a recurred mass in the mandible for 1 month after the operation of mandibular tumor. The first excisional specimen was initially diagnosed as ossifying fibroma in another hospital. Histopathologic examination revealed the tumor with a hybrid spindle cell and epithelioid cytomorphology, spindle cells and spindle-to-epithelioid cells with eosinophilic and rich cytoplasm, with high-grade features, prominent nucleoli and some atypical mitosis. Immunohistochemical analysis revealed positivity for desmin, MYOD1, pan-keratin, ALK (5A4), ALK (D5F3). Based on the morphology and immunophenotype, molecular studies were performed, which revealed a FUS::TFCP2 fusion transcript, confirming the diagnosis of Rhabdomyosarcoma with FUS::TFCP2 fusion. Making a correct diagnosis is primarily dependent on awareness by the pathologist of this rare subtype of RMS and careful histopathological evaluation, supported by immunohistochemical and molecular analysis, to avoid potential diagnostic pitfalls. [ABSTRACT FROM AUTHOR]

There are no medical therapies to stop progression of pulmonary emphysema. In chronic obstructive pulmonary disease (COPD), lung NK cell cytotoxicity towards lung parenchymal cells is increased, lung dendritic cells are activated, and lung regulatory T cell (Treg) numbers are decreased. We propose that re-establishing the balance between these three cell types might be a crucial component to arresting emphysema progression. Developing Treg-based therapies for COPD may require strategies to ensure the stability of Treg phenotypes. An increased understanding of the presumed dysregulated immune interactions between dendritic cells (DCs), natural killer cells (NK), and regulatory T cells (Tregs) in COPD might lead to novel and potentially disease-modifying COPD therapies that target specific cell types. Chronic obstructive pulmonary disease (COPD) is characterized by infiltration of the airways and lung parenchyma by inflammatory cells. Lung pathology results from the cumulative effect of complex and aberrant interactions between multiple cell types. However, three cell types, natural killer cells (NK), dendritic cells (DCs), and regulatory T cells (Tregs), are understudied and underappreciated. We propose that their mutual interactions significantly contribute to the development of COPD. Here, we highlight recent advances in NK, DC, and Treg biology with relevance to COPD, discuss their pairwise bidirectional interactions, and identify knowledge gaps that must be bridged to develop novel therapies. Understanding their interactions will be crucial for therapeutic use of autologous Treg, an approach proving effective in other diseases with immune components. [ABSTRACT FROM AUTHOR]

Ethyl pyruvate (EP) is a redox-active compound that has been previously shown to be effective in restraining immune hyperactivity in animal models of various autoimmune and chronic inflammatory diseases. Importantly, EP has also been proven to have a potent tolerogenic effect on dendritic cells (DCs). Here, the influence of EP on the signaling pathways in DCs relevant for their tolerogenicity, including anti-inflammatory NRF2 and pro-inflammatory NF-κB, was explored. Specifically, the effects of EP on DCs obtained by GM-CSF-directed differentiation of murine bone marrow precursor cells and matured under the influence of lipopolysaccharide (LPS) were examined via immunocytochemistry and RT-PCR. EP counteracted LPS-imposed morphological changes and down-regulated the LPS-induced expression of pro-inflammatory mediators in DCs. While it reduced the activation of NF-κB, EP potentiated NRF2 and downstream antioxidative molecules, thus implying the regulation of NRF2 signaling pathways as the major reason for the tolerizing effects of EP on DCs. [ABSTRACT FROM AUTHOR]

The bleomycin-induced scleroderma model is a well-established and dependable method for creating a mouse model of SSc (systemic sclerosis). In the field of skin connective tissue diseases, increasing evidence from clinical and animal experiments suggests that TLRs (Toll-like receptors) play an important role in several diseases. This study aimed to determine the role of TLR7 (Toll-like receptor 7) and TLR9 (Toll-like receptor 9) in the mechanisms of immune abnormalities and fibrosis in SSc. This study used TLR7-KO mice (TLR7-knockout mice with a balb/c background) and TLR9-KO mice (TLR9-knockout mice with a balb/c background) as well as WT mice (wild-type balb/c mice). All three kinds of mice were induced by BLM (bleomycin) in a scleroderma model as the experimental group; meanwhile, WT mice treated with PBS (phosphate-buffered saline) were used as the control group. We analyzed the fibrotic phenotype and the immunological abnormality phenotype of TLR7-deficient and TLR9-deficient mice in the SSc disease model using flow cytometry, RT-PCR (reverse transcription–polymerase chain reaction), a histological examination, and IHC (immunohistochemical staining). In a mouse model of SSc disease, the deletion of TLR7 attenuated skin and lung fibrosis, while the deletion of TLR9 exacerbated skin and lung fibrosis. The deletion of TLR7 resulted in a relative decrease in the infiltration and expression of various pro-inflammatory and fibrotic cells and cytokines in the skin. On the other hand, the deletion of TLR9 resulted in a relative increase in the infiltration and expression of various pro-inflammatory and cytokine-inhibiting cells and cytokines in the skin. Under the influence of pDCs (plasmacytoid dendritic cells), the balances of Beff/Breg (IL-6 + CD19 + B cell/IL-10 + CD19 + B cell), Th17/Treg (IL-17A + CD4 + T cell/Foxp3 + CD25 + CD4 + T cell), M1/M2 (CD86 + macrophage/CD206 + macrophage), and Th1/Th2 (TNFα + CD3 + CD4 + T cell/IL-4 + CD3 + CD4 + T cell) were biased towards the suppression of inflammation and fibrosis as a result of the TLR7 deletion. Comparatively, the balance was biased towards promoting inflammation and fibrosis due to the TLR9 deletion. In the SSc model, TLR7 promoted inflammation and fibrosis progression, while TLR9 played a protective role. These results suggest that TLR7 and TLR9 play opposite roles in triggering SSc to produce immune system abnormalities and skin fibrosis. [ABSTRACT FROM AUTHOR]

We have previously performed preclinical studies with the oxidized mannan-conjugated peptide MOG35–55 (OM-MOG35–55) in vivo (EAE mouse model) and in vitro (human peripheral blood) and demonstrated that OM-MOG35–55 suppresses antigen-specific T cell responses associated with autoimmune demyelination. Based on these results, we developed different types of dendritic cells (DCs) from the peripheral blood monocytes of patients with multiple sclerosis (MS) or healthy controls presenting OM-MOG35–55 or MOG-35–55 to autologous T cells to investigate the tolerogenic potential of OM-MOG35–55 for its possible use in MS therapy. To this end, monocytes were differentiated into different DC types in the presence of IL-4+GM-CSF ± dexamethasone (DEXA) ± vitamin D3 (VITD3). At the end of their differentiation, the DCs were loaded with peptides and co-cultured with T cells +IL-2 for 4 antigen presentation cycles. The phenotypes of the DC and T cell populations were analyzed using flow cytometry and the secreted cytokines using flow cytometry or ELISA. On day 8, the monocytes had converted into DCs expressing the typical markers of mature or immature phenotypes. Co-culture of T cells with all DC types for 4 antigen presentation cycles resulted in an increase in memory CD4+ T cells compared to memory CD8+ T cells and a suppressive shift in secreted cytokines, mainly due to increased TGF-β1 levels. The best tolerogenic effect was obtained when patient CD4+ T cells were co-cultured with VITD3-DCs presenting OM-MOG35–55, resulting in the highest levels of CD4+PD-1+ T cells and CD4+CD25+Foxp3+ Τ cells. In conclusion, the tolerance induction protocols presented in this work demonstrate that OM-MOG35–55 could form the basis for the development of personalized therapeutic vaccines or immunomodulatory treatments for MS. [ABSTRACT FROM AUTHOR]

Cancer immunotherapy using antigen-pulsed dendritic cells can induce strong cellular immune responses by priming cytotoxic T lymphocytes. In this study, we pulsed tumor cell lysates with VP-R8, a cell-penetrating D-octaarginine-linked co-polymer of N-vinylacetamide and acrylic acid (PNVA-co-AA), into the DC2.4 murine dendritic cell line to improve antigen uptake and then determined the anti-tumor effect in tumor-bearing mice. DC2.4 cells were pulsed with the cell lysate of EL4, a murine lymphoma cell line, and VP-R8 to generate the DC2.4 vaccine. For the in vivo study, DC2.4 cells pulsed with EL4 lysate and VP-R8 were subcutaneously injected into the inguinal lymph node to investigate the anti-tumor effect against EL4 and EL4-specific T cell immune responses. VP-R8 significantly improved antigen uptake into DC2.4 compared to conventional keyhole limpet hemocyanin (p < 0.05). The expression of MHC class I, MHC class II, and CD86 in DC2.4 cells significantly increased after pulsing tumor lysates with VP-R8 compared to other treatments (p < 0.05). The intra-lymph node injection of DC2.4 pulsed with both VP-R8 and EL4 lysate significantly decreased tumor growth compared to DC2.4 pulsed with KLH and lysates (p < 0.05) and induced tumor-infiltrating CD8T cells. The DC2.4 vaccine also remarkably increased the population of IFN-gamma-producing T cells and CTL activity against EL4 cells. In conclusion, we demonstrated that VP-R8 markedly enhances the efficiency of dendritic cell-based vaccines in priming robust anti-tumor immunity, suggesting its potential as a beneficial additive for dendritic cell-based immunotherapy. [ABSTRACT FROM AUTHOR]

Simple Summary: Glioblastoma is one of the most dangerous tumors of the central nervous system, and still cannot be fully overcome. We still mainly rely on standard treatments combining chemotherapy, radiotherapy, and surgery in various combinations. However, advances in technology, particularly biotechnology, are allowing the introduction of new, more precise therapies. These are more personalized, targeting a specific stage of tumor development or a particular cell population. The treatment of glioma is one of the areas in which we see more and more personalized medicine. In this article, we have tried to describe the current state of knowledge regarding the use of modern therapies in treating glioblastoma and the primary concerns. Glioblastoma is the most common malignant primary brain tumor in the adult population, with an average survival of 12.1 to 14.6 months. The standard treatment, combining surgery, radiotherapy, and chemotherapy, is not as efficient as we would like. However, the current possibilities are no longer limited to the standard therapies due to rapid advancements in biotechnology. New methods enable a more precise approach by targeting individual cells and antigens to overcome cancer. For the treatment of glioblastoma, these are gamma knife therapy, proton beam therapy, tumor-treating fields, EGFR and VEGF inhibitors, multiple RTKs inhibitors, and PI3K pathway inhibitors. In addition, the increasing understanding of the role of the immune system in tumorigenesis and the ability to identify tumor-specific antigens helped to develop immunotherapies targeting GBM and immune cells, including CAR-T, CAR-NK cells, dendritic cells, and immune checkpoint inhibitors. Each of the described methods has its advantages and disadvantages and faces problems, such as the inefficient crossing of the blood–brain barrier, various neurological and systemic side effects, and the escape mechanism of the tumor. This work aims to present the current modern treatments of glioblastoma. [ABSTRACT FROM AUTHOR]

Epithelial barrier damage plays a central role in the development and maintenance of allergic inflammation. Rises in the epithelial barrier permeability of airways alter tissue homeostasis and allow the penetration of allergens and other external agents. Different factors contribute to barrier impairment, such as eosinophilic infiltration and allergen protease action—eosinophilic cationic proteins' effects and allergens' proteolytic activity both contribute significantly to epithelial damage. In the airways, allergen proteases degrade the epithelial junctional proteins, allowing allergen penetration and its uptake by dendritic cells. This increase in allergen–immune system interaction induces the release of alarmins and the activation of type 2 inflammatory pathways, causing or worsening the main symptoms at the skin, bowel, and respiratory levels. We aim to highlight the molecular mechanisms underlying allergenic protease-induced epithelial barrier damage and the role of immune response in allergic asthma onset, maintenance, and progression. Moreover, we will explore potential clinical and radiological biomarkers of airway remodeling in allergic asthma patients. [ABSTRACT FROM AUTHOR]

Alopecia areata (AA) is an autoimmune-mediated disorder in which the proximal hair follicle (HF) attack results in non-scarring partial to total scalp or body hair loss. Despite the growing knowledge about AA, its exact cause still needs to be understood. However, immunity and genetic factors are affirmed to be critical in AA development. While the genome-wide association studies proved the innate and acquired immunity involvement, AA mouse models implicated the IFN-γ- and cytotoxic CD8+ T-cell-mediated immune response as the main drivers of disease pathogenesis. The AA hair loss is caused by T-cell-mediated inflammation in the HF area, disturbing its function and disrupting the hair growth cycle without destroying the follicle. Thus, the loss of HF immune privilege, autoimmune HF destruction mediated by cytotoxic mechanisms, and the upregulation of inflammatory pathways play a crucial role. AA is associated with concurrent systemic and autoimmune disorders such as atopic dermatitis, vitiligo, psoriasis, and thyroiditis. Likewise, the patient's quality of life (QoL) is significantly impaired by morphologic disfigurement caused by the illness. The patients experience a negative impact on psychological well-being and self-esteem and may be more likely to suffer from psychiatric comorbidities. This manuscript aims to present the latest knowledge on the pathogenesis of AA, which involves genetic, epigenetic, immunological, and environmental factors, with a particular emphasis on immunopathogenesis. [ABSTRACT FROM AUTHOR]

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive myeloid malignancy associated with a poor prognosis. Although allogeneic hematopoietic stem cell transplantation (allo-HSCT) has emerged as a potential treatment strategy for BPDCN, standardized conditioning regimens remain lacking. In this manuscript, we present two cases of BPDCN that were treated with a thiotepa-busulfan-fludarabine (TBF)-based conditioning regimen prior to allo-HSCT. Both cases demonstrated complete remission post-transplantation, sustained donor chimerism, and remission maintenance, suggesting the potential efficacy of the TBF conditioning regimen for BPDCN transplantation. Given the small sample size in our study, we emphasize caution and advocate for larger studies to confirm the efficacy of TBF in the treatment of BPDCN. [ABSTRACT FROM AUTHOR]

Studying cellular mechanoresponses during cancer metastasis is limited by sample variation or complex protocols that current techniques require. Metastasis is governed by mechanotransduction, whereby cells translate external stimuli, such as circulatory fluid shear stress (FSS), into biochemical cues. We present high-throughput, semi-automated methods to expose cells to FSS using the VIAFLO96 multichannel pipetting device custom-fitted with 22 G needles, increasing the maximum FSS 94-fold from the unmodified tips. Specifically, we develop protocols to semi-automatically stain live samples and to fix, permeabilize, and intracellularly process cells for flow cytometry analysis. Our first model system confirmed that the pro-apoptotic effects of TRAIL therapeutics in prostate cancer cells can be enhanced via FSS-induced Piezo1 activation. Our second system implements this multiplex methodology to show that FSS exposure (290 dyn cm−2) increases activation of murine bone marrow-derived dendritic cells. These methodologies greatly improve the mechanobiology workflow, offering a high-throughput, multiplex approach. The authors present a multiplex, high-throughput method based on a commercially available multipipettor device to study mechanotransduction in cancer cells and immune cells in response to physiological fluid shear stress. [ABSTRACT FROM AUTHOR]

Nodal T‐follicular helper cell lymphoma (TFHL) is a subset of T‐cell lymphoma and frequently co‐occurs with Epstein–Barr virus (EBV)‐positive B‐cell lymphoma but not with T/NK‐cell lymphoma. Recently, a new entity with a worse prognosis, called EBV‐positive nodal T/NK‐cell lymphoma (NTNKL) has been established. Here, we report an autopsy case of synchronous multiple lymphomas, including TFHL and NTNKL. The patient was a 78‐year‐old female admitted with pneumonia. Although pneumonic symptoms were improved, fever, pancytopenia, and disseminated intravascular coagulation emerged, implicating lymphoma. She died on the 21st hospital day without a definitive diagnosis. The autopsy revealed the enlargement of multiple lymph nodes throughout her body. Histological analysis revealed three distinct regions in the left inguinal lymph node. The first region consists of small‐sized lymphocytes with T‐follicular helper phenotype and extended follicular dendritic cell meshwork, indicating TFHL. The second region included EBV‐positive large B cells. The third region comprised EBV‐positive large cells with cytotoxic T/NK cell phenotype, indicating NTNKL. Clonality analysis of the first and the third regions showed different patterns. Since various hematopoietic malignancies progress from common clonal hematopoiesis according to existing literature, this case may help to understand TFHL and NTNKL. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a type of autoimmune disease that results in immune disorder and excessive inflammatory response due to a reduction of self-tolerance. Invariant natural killer T (iNKT) cells can effectively alleviate clinical symptoms and hyper-inflammation in RA, but their mechanism of action is not well-defined. This study aims to investigate the mechanism of iNKT cell therapy for RA. We established a DBA/1 mouse model for RA and treated it with specific iNKT cells. A cytometric bead array was used to measure the amounts of cytokines in the serum. Flow cytometry was then employed to identify different subsets of helper T cells (Th), the frequency of conventional dendritic cells (cDC), the expression of CD80, CD86, programmed cell death ligand 1 (PD-L1), and PD-L2 on cDC surfaces, and associated pathway proteins. iNKT cell treatment reduced Th1/Th2 and Th17/ regulatory T (Treg) cell ratios while increasing interleukin-4 (IL-4) and IL-10. It enhanced the generation of immature cDCs, and it upregulated the level of PD-L2 by stimulating the signal transducer and activator of transcription 3 (STAT3) signaling pathway. Meanwhile, it activated the extracellular signal-regulated kinase 1/2 (ERK1/2) pathway and inhibited the nuclear factor kappa B (NF-κB) pathway. According to our findings, iNKT cell treatment increased the expression of phosphates STAT3 in lymph node cDC, causing them to upregulate PD-L2 molecules. While activating the ERK1/2 pathway and inhibiting the NF-κB pathway, tolerogenic cDC was produced, restoring immune homeostasis and correcting excessive inflammation. These results deliver new insights into the treatment of RA by iNKT cells. [ABSTRACT FROM AUTHOR]

Esophageal squamous cell carcinoma (ESCC) is characterized by molecular heterogeneity with various immune cell infiltration patterns, which have been associated with therapeutic sensitivity and resistance. In particular, dendritic cells (DCs) are recently discovered to be associated with prognosis and survival in cancer. However, how DCs differ among ESCC patients has not been fully comprehended. Recently, the advance of single-cell RNA sequencing (scRNA-seq) enables us to profile the cell types, states, and lineages in the heterogeneous ESCC tissues. Here, we dissect the ESCC tumor microenvironment at high resolution by integrating 192,078 single cells from 60 patients, including 4379 DCs. We then used Scissor, a method that identifies cell subpopulations from single-cell data that are associated bulk samples with genomic and clinical information, to stratify DCs into Scissorhi and Scissorlow subtypes. We applied the Scissorhi gene signature to stratify ESCC scRNAseq patient, and we found that PD-L1, TIGIT, PVR and IL6 ligand-receptor-mediated cell interactions existed mainly in Scissorhi patients. Finally, based on the Scissor results, we successfully developed a validated prognostic risk model for ESCC and further validated the reliability of the risk prediction model by recruiting 40 ESCC clinical patients. This information highlights the importance of these genes in assessing patient prognosis and may help in the development of targeted or personalized therapies for ESCC. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a progressive autoimmune disease and drug therapy has been restricted due to poor therapeutic efficacy and adverse effects. In RA synovium, dendritic cells present self-antigens to activate cascade immune pathway. Furthermore, downstream macrophages secrete high levels of pro-inflammatory cytokines; Hyperplasia of activated synovial fibroblasts (FLS) is responsible for hypoxic synovium microenvironment, secretion of cytokines/chemokines and erosion of bone/cartilage tissues. Positive feedback loop of inflammation between macrophages and FLS independent of antigen-presentation is constructed. Herein, an injectable pH-sensitive peptide hydrogel encapsulating siRNA/Methotrexate-polyethyleneimine (siMP, including sip65MP, sip38MP, siCD86MP) and Bismuthene nanosheet/Methotrexate-polyethyleneimine (BiMP) is successfully developed. Among them, siCD86MP reduces protein level of co-stimulatory molecule CD86 while sip65MP and sip38MP separately inhibit NF-κB and MAPK-p38 pathways of macrophages and FLS to suppress secretion of cytokines and MMPs. Meanwhile, reduction in anti-apoptotic property of FLS induced by inhibition of NF-κB pathway has a synergistic effect with photodynamic therapy (PDT) and photothermal therapy (PTT) mediated by BiMP for FLS elimination, effectively ameliorating hypoxic synovium microenvironment. After being injected into synovium, hydrogel responds to acidic microenvironment and serves as a reservoir for sustained drug release and inherent retention capacity of which enables cationic nanoparticles to bypass tissue barrier for precise synovium targeting. This brand-new drug delivery system combines modulating cascade immune pathway from beginning to end by RNAi and eliminating FLS for improving synovium microenvironment by phototherapy together, providing a robust strategy for clinical RA treatment. In RA synovium, dendritic cells present self-antigens to activate the whole inflammatory pathway. Inhibiting antigen-presentation could effectively block the initiation of entire pathway. However, the downstream macrophages secrete high levels of pro-inflammatory cytokines, while excessively proliferated synovial fibroblasts (FLS) are responsible for hypoxia microenvironment, cytokine/chemokine release, bone/cartilage erosion, thus constructing an immune cycle independent of antigen-presentation together with macrophages. In this timely research, we successfully developed an implantable and pH-sensitive peptide hydrogel loading siRNA/methotrexate-polyethyleneimine (siMP: siCD86MP, sip65MP, sip38MP) and bismuthene nanosheet/methotrexate-polyethyleneimine (BiMP). siCD86MP can reduce the protein level of co-stimulatory molecule CD86 to block the initiation of inflammatory pathway. sip65MP and sip38MP can inhibit NF-κB and MAPK-p38 pathways in macrophages and FLS to ameliorate secretion of cytokines and MMPs, fundamentally blocking inflammatory circulation. Meanwhile, reduction in anti-apoptosis property of FLS induced by siMP had the synergistic effect with PDT and PTT of BiMP for FLS elimination, effectively ameliorating synovium microenvironment. After injection into synovium, the hydrogel responded to the acidic microenvironment and served as a drug reservoir for sustained drug release, while reducing systematic toxicity of cationic nanoparticles. The inherent retention capacity of hydrogel enabled nanoparticles to bypass the tissue barrier and achieve precise targeting. This brand-new drug delivery system combines modulating inflammation pathways from beginning to end by RNAi and eliminating FLS by phototherapy for improving synovium microenvironment together, providing a robust strategy for RA treatment. [Display omitted] • siRNA modulated cascade immune activation through inhibiting upstream antigen-presentation and downstream inflammatory circulation. • Bismuthene nanosheets exerted efficient PDT&PTT therapy to eliminate FLS for alleviating hypoxic synovium microenvironment. • Modulation of cascade immune activation and alleviating hypoxia microenvironment can synergistically treat RA. • Nap Hydrogel possessed excellent biocompatibility, injectability, self-healing, pH responsiveness, synovium targeting and retention. [ABSTRACT FROM AUTHOR]

Activation of the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway is an effective way to initiate an immune response against tumors, and the research on agonists targeting STING has become a new hotspot in the development of antitumor drugs. However, as a novel STING agonist, the limited bioavailability and activation routes of manganese ions (Mn2+) significantly hinder its antitumor effects. To address these challenges, we have designed a metal-coordinated nucleoside metabolic inhibitor (gemcitabine, Gem)-induced metal nanotheranostic (MGP) with PEGylation. This formulation synergistically enhanced the immune response against cancer cells by sensitizing the cGAS-STING pathway and promoting immunogenic cell death (ICD). Modified with PEG derivatives, MGP was efficiently delivered to the tumor site and was internalized by cancer cells. Upon internalization, the release of Mn2+ triggered the activation of the cGAS-STING pathway, while the release of Gem induced DNA damage. On the one hand, the damaged DNA caused by Gem leaked into the cytoplasm, synergistically amplified Mn2+-induced activation of the cGAS-STING pathway, and induced the production of the tumor cytotoxic factor IFN-β. On the other hand, Mn2+-mediated chemodynamic therapy (CDT) exhibited an ICD effect, which further synergized with the activation of the cGAS-STING pathway to promote dendritic cells (DCs) maturation and antigen-specific T cells infiltration. Both in vitro and in vivo studies have demonstrated that MGP nanotheranostics could elicit a robust antitumor effect, especially when combined with anti-PD-1. This study provided a new paradigm for intensifying immune activation by constructing metal coordination nanotheranostics. [Display omitted] • Metal coordination nanotheranostics for tumor immunotherapy. • Mn2+ induces chemodynamic therapy and activates the STING pathway. • Chemotherapy-elicited damaged DNA sensitizes the STING pathway activation. [ABSTRACT FROM AUTHOR]

Adoptive cell therapy with tumor-infiltrating T cells (TILs) has generated exciting clinical trial results for the treatment of unresectable solid tumors. However, solid tumors remain difficult targets for adoptively transferred T cells, due in part to poor migration of TILs to the tumor, physical barriers to infiltration, and active suppression of TILs by the tumor. Furthermore, a highly skilled team is required to obtain tumor tissue, isolate and expand the TILs ex vivo, and reinfuse them into the patient, which drives up costs and limits patient access. Here, we describe a cell-free polymer implant designed to recruit, genetically reprogram and expand host T cells at tumor lesions in situ. Importantly, the scaffold can be fabricated on a large scale and is stable to lyophilization. Using a mouse breast cancer model, we show that the implants quickly and efficiently amass cancer-specific host lymphocytes at the tumor site in quantities sufficient to bring about long-term tumor regression. Given that surgical care is the mainstay of cancer treatment for many patients, this technology could be easily implemented in a clinical setting as an add-on to surgery for solid tumors. Furthermore, the approach could be broadened to recruit and genetically reprogram other therapeutically desirable host cells, such as macrophages, natural killer cells or dendritic cells, potentially boosting the antitumor effectiveness of the implant even more. Our group developed an implantable device that (1) recruits T cells in situ, (2) genetically equips them with tumor-specific receptors, and (iii) rapidly expands and disperses them into solid tumor lesions. More specifically, the implant is based on a porous collagen scaffold (inherently supporting rapid T-cell migration), which is functionalized with a potent chemoattractant (CCL21) to recruit host T cells. To efficiently reprogram and expand recruited T cells within the scaffold, vectors encoding a tumor-specific receptor (chimeric antigen receptor in our study) and stimulatory anti- CD3/CD28 antibodies were co-encapsulated. All these components can be manufactured at large-scale and without the need to prepare a cellular product for each individual patient, and the final device can be frozen and stored until use. [Display omitted] • Rationally designed biomaterial scaffolds recruit, reprogram, expand and release human T cells. • Biomaterial scaffolds can efficiently transduce host T cells with tumor-specific CAR transgenes. • Scaffold-mediated in situ programming of CAR T-cells can improve survival of mice with established disease. [ABSTRACT FROM AUTHOR]

Different from the direct delivery of chemodynamic agents into tumor tissue for chemodynamic therapy (CDT), this work reports the fabrication of heterojunction sonosensitizers (CD/TiSe2) for the in situ generation of chemodynamic agents by responding to tumor microenvironment (TME), realizing the in situ CDT‐enhanced sono‐immunotherapy. The in situ redox of TiSe2 in acidic TME leads to the formation of TiOxSe2−x containing Se (0), selenate, and Ti3+/Ti4+ redox couple, which can facilitate in situ CDT through a Ti3+‐mediated Fenton‐like reaction and consume overexpressed glutathione (GSH) via a Ti4+‐mediated GSH depletion. Moreover, Se ions generated through the in situ redox process promote the maturation of dendritic cells, consequently activating the adaptive immune responses. In another aspect, the construction of heterojunctions within carbon dots and TiSe2 improves the reactive oxygen species (ROS) generation efficiency of TiSe2 in a cascaded manner, which enhances the sonodynamic activity and amplifies the chemodynamic performance. More importantly, the ROS produced by in situ CDT and sonodynamic therapy efficiently triggers immunogenic cell death through a synergistic therapy based on the elicitation of antitumor immunity with the aid of an immune checkpoint blockade. This work thus provides a distinct paradigm of transition metal selenide‐originated in situ Fenton‐like agent generation for in situ CDT‐enhanced sono‐immunotherapy. [ABSTRACT FROM AUTHOR]

Simple Summary: There are three main types of neoplastic plasmacytoid dendritic cell (pDC) proliferations: blastic plasmacytoid dendritic cell neoplasm (BPDCN), acute myeloid leukemia with pDC differentiation (pDC-AML), and mature pDC proliferation (MPDCP). In this review, we focus on flow cytometry immunophenotyping analysis, discussing the immunophenotypes of each type of pDC proliferation, their differential diagnoses, and the challenges and pitfalls in evaluating these pDC proliferations. In this review, we aim to provide a summary of the diverse immunophenotypic presentations of distinct entities associated with plasmacytoid dendritic cell (pDC) proliferation. These entities include the following: (1) blastic plasmacytoid dendritic cell neoplasm (BPDCN); (2) mature pDC proliferation (MPDCP), most commonly seen in chronic myelomonocytic leukemia (CMML); and (3) myeloid neoplasms with pDC differentiation, in which pDCs show a spectrum of maturation from early immature pDCs to mature forms, most commonly seen in acute myeloid leukemia (pDC-AML). Our aim is to provide a flow cytometry diagnostic approach to these distinct and sometimes challenging entities and to clarify the immunophenotypic spectrum of neoplastic pDCs in different disease presentations. In this review, we also cover the strategies in the evaluation of residual disease, as well as the challenges and pitfalls we face in the setting of immune and targeted therapy. The differential diagnosis will also be discussed, as blasts in some AML cases can have a pDC-like immunophenotype, mimicking pDCs. [ABSTRACT FROM AUTHOR]

Simple Summary: The United States is suffering from an epidemic associated with infections with the Human Papilloma Virus (HPV) that are responsible for the development of head and neck squamous cell carcinoma (HNSCC). Our study aims to characterize immune profiles, and the oral microbiota in oropharyngeal tumors associated with anti-PD-1 treatment response in a preclinical murine model for HPV+ oropharyngeal cancer. We confirmed 16 immune markers and specific bacteria in the oral cavity that differentiate between treatment responders and non-responders, which may be used as potential biomarkers for PD-1 blockade response. The United States is suffering from an epidemic associated with high-risk strains of the Human Papillomavirus (HPV) predominantly responsible for the development of head and neck squamous cell carcinoma (HNSCC). Treatment with immune checkpoint inhibitors targeting programmed death 1 (PD-1) or its ligand PD-L1 has shown poor efficacy in HNSCC patients, observing only a 20–30% response. Therefore, biological marker identification associated with PD-1 blockade response is important to improve prognosis and define novel therapeutics for HNSCC patients. Therapy response was associated with increased frequencies of activated CD27+T cells, activated CD79a+ B cells, antigen-presenting CD74+ dendritic and B cells, and PD-L1+ and PD-L2+ myeloid-derived suppressor cells (MDSCs). The oral microbiota composition differed significantly in mice bearing tongue tumors and treated with anti-PD-1. A higher abundance of Allobaculum, Blautia, Faecalibacterium, Dorea, or Roseburia was associated with response to the therapy. However, an increase in Enterococcus was attributed to tongue tumor-bearing non-responding mice. Our findings indicate that differences in immune phenotypes, protein expression, and bacterial abundance occur as mice develop tongue tumors and are treated with anti-PD-1. These results may have a clinical impact as specific bacteria and immune phenotype could serve as biomarkers for treatment response in HNSCC. [ABSTRACT FROM AUTHOR]

Dendritic cells (DCs) are essential orchestrators of immune responses and represent potential targets for immunomodulation in autoimmune diseases. Human amniotic fluid secretome is abundant in immunoregulatory factors, with extracellular vesicles (EVs) being a significant component. However, the impact of these EVs on dendritic cells subsets remain unexplored. In this study, we investigated the interaction between highly purified dendritic cell subsets and EVs derived from amniotic fluid stem cell lines (HAFSC‐EVs). Our results suggest that HAFSC‐EVs are preferentially taken up by conventional dendritic cell type 2 (cDC2) through CD29 receptor‐mediated internalization, resulting in a tolerogenic DC phenotype characterized by reduced expression and production of pro‐inflammatory mediators. Furthermore, treatment of cDC2 cells with HAFSC‐EVs in coculture systems resulted in a higher proportion of T cells expressing the regulatory T cell marker Foxp3 compared to vehicle‐treated control cells. Moreover, transfer of HAFSC‐EV‐treated cDC2s into an EAE mouse model resulted in the suppression of autoimmune responses and clinical improvement. These results suggest that HAFSC‐EVs may serve as a promising tool for reprogramming inflammatory cDC2s towards a tolerogenic phenotype and for controlling autoimmune responses in the central nervous system, representing a potential platform for the study of the effects of EVs in DC subsets. [ABSTRACT FROM AUTHOR]

Increasing immunotherapy response rate and durability can lead to significant improvements in cancer care. To address this challenge, a novel multivalent immune checkpoint therapeutic platform is constructed through site‐specific ligation of anti‐PD‐L1 nanobody (Nb) on ferritin (Ftn) nanocage. Nb‐Ftn blocks PD‐1/PD‐L1 interaction and downregulates PD‐L1 levels via endocytosis‐induced degradation. In addition, the cage structure of Ftn allows encapsulation of indocyanine green (ICG), an FDA‐approved dye. Photothermal treatment with Nb‐Ftn@ICG induces immunogenic death of tumor cells, which improves systemic immune response via maturation of dendritic cells and enhanced infiltration of T cells. Moreover, Nb‐Ftn encapsulation significantly enhances cellular uptake, tumor accumulation and retention of ICG. In vivo assays showed that this nanoplatform ablates the primary tumor, suppresses abscopal tumors and inhibits tumor metastasis, leading to a prolonged survival rate. This work presents a novel strategy for improving cancer immunotherapy using multivalent nanobody‐ferritin conjugates as immunological targeting and enhancing carriers. [ABSTRACT FROM AUTHOR]

R-spondin 1 (RSPO1), which encodes a secretory-activating protein, is a promising therapeutic target for various tumors. The aim of this study was to establish a robust RSPO1-related signature specific to esophageal cancer (ESCA). Our comprehensive study involved meticulous analysis of RSPO1 expression in ESCA tissues and validation across ESCA cell lines and clinical samples using The Cancer Genome Atlas (TCGA) and GTEx databases. Using TCGA-ESCA dataset, we employed single-sample gene set enrichment analysis (ssGSEA) to elucidate the complex interaction between RSPO1 expression and the abundance of 22 specific immune cell types infiltrating ESCA. The biological significance of RSPO1 was further elucidated using KEGG, GO, and GSEA, demonstrating its relevance to pivotal tumor and immune pathways. This study culminated in the construction of prognostic nomograms enriched by calibration curves, facilitating the projection of individual survival probabilities at intervals of one, three, and five years. A substantial decrease in RSPO1 expression was observed within ESCA tissues and cell lines compared to their normal esophageal counterparts, and a significant decrease in the proportion of activated dendritic cells was evident within ESCA, accompanied by an augmented presence of macrophages and naive B cells relative to normal tissue. GSEA and KEGG analyses showed that RSPO1 was associated with tumor and immune pathways. Additionally, an independent prognostic risk score based on the RSPO1-related gene signature was developed and validated for patients with ESCA. Finally, RT-qPCR and western blotting were performed to confirm RSPO1 expression in normal and ESCA cell lines and tissue samples. In summary, our investigation underscores the pivotal role of RSPO1 in orchestrating tumor immunity and proposes RSPO1 as a prospective target for immunotherapeutic interventions in ESCA. Furthermore, the intricate profile of the two RSPO1-related genes has emerged as a promising predictive biomarker with notable potential for application in ESCA. [ABSTRACT FROM AUTHOR]

Background: To elucidate the mechanism of dysfunction of tolerogenic dendritic cells (DCs) is of significance. Telomerase involves the regulation of the cell fate and activities. The objective of this study is to investigate the role of telomerase reverse transcriptase (TERT) in regulating the tolerogenic feature of DCs. Methods: The telomerase was assessed in DCs, which were collected from patients with allergic rhinitis (AR), healthy control (HC) subjects, and mice. RNAs were extracted from DCs, and analyzed by RNA sequencing (RNAseq), real-time quantitative RT-PCR, and Western blotting. Results: The results showed that expression of TERT was higher in peripheral DCs of AR patients. The expression of IL10 in DCs was negatively correlated with the levels of TERT expression. Importantly, the levels of TERT mRNA in DCs were associated with the AR response in patients with AR. Endoplasmic reticulum (ER) stress promoted the expression of Tert in DCs. Sensitization with the ovalbumin-aluminum hydroxide protocol increased the expression of Tert in DCs by exacerbating ER stress. TERT interacting with c-Maf (the transcription factor of IL-10) inducing protein (CMIP) in DCs resulted in CMIP ubiquitination and degradation, and thus, suppressed the production of IL-10. Inhibition of Tert in DCs mitigated experimental AR. Conclusions: Elevated amounts of TERT were detected in DCs of patients with AR. The tolerogenic feature of DCs was impacted by TERT. Inhibited TERT attenuated experimental AR. [ABSTRACT FROM AUTHOR]

CD200 is an anti-inflammatory protein that facilitates signal transduction through its receptor, CD200R, in cells, resulting in immune response suppression. This includes reducing M1-like macrophages, enhancing M2-like macrophages, inhibiting NK cell cytotoxicity, and downregulating CTL responses. Activation of CD200R has been found to modulate dendritic cells, leading to the induction or enhancement of Treg cells expressing Foxp3. However, the precise mechanisms behind this process are still unclear. Our previous study demonstrated that B cells in Peyer's patches can induce Treg cells, so-called Treg-of-B (P) cells, through STAT6 phosphorylation. This study aimed to investigate the role of CD200 in Treg-of-B (P) cell generation. To clarify the mechanisms, we used wild-type, STAT6 deficient, and IL-24 deficient T cells to generate Treg-of-B (P) cells, and antagonist antibodies (anti-CD200 and anti-IL-20RB), an agonist anti-CD200R antibody, CD39 inhibitors (ARL67156 and POM-1), a STAT6 inhibitor (AS1517499), and soluble IL-20RB were also applied. Our findings revealed that Peyer's patch B cells expressed CD200 to activate the CD200R on T cells and initiate the process of Treg-of-B (P) cells generation. CD200 and CD200R interaction triggers the phosphorylation of STAT6, which regulated the expression of CD200R, CD39, and IL-24 in T cells. CD39 regulated the expression of IL-24, which sustained the expression of CD223 and IL-10 and maintained the cell viability. In summary, the generation of Treg-of-B (P) cells by Peyer's patch B cells was through the CD200R-STAT6-CD39-IL-24 axis pathway. [ABSTRACT FROM AUTHOR]

Background: Restoring impaired peripheral immune tolerance is the primary challenge in treating autoimmune diseases. Our previous research demonstrated the effectiveness of small spleen peptides (SSPs), a fraction of low molecular weight proteins, in inhibiting the progression of psoriatic arthritis, even in the presence of high levels of the proinflammatory cytokine TNFα in the bloodstream. When specifically targeting dendritic cells (DCs), SSPs transform them into tolerogenic cells, which efficiently induce the development of regulatory Foxp3+ Treg cells. In this study, we provide further insights into the mechanism of action of SSPs. Results: We found that SSPs stimulate the activation of the mTOR signaling pathway in dendritic cells, albeit in a different manner than the classical immunogenic stimulus LPS. While LPS-induced activation is rapid, strong, and sustained, the activity induced by SSPs is delayed, less intense, yet still significant. These distinct patterns of activation, as measured by phosphorylation of key components of the pathway are also observed in response to other immunogenic and tolerogenic stimuli such as GM-CSF + IL-4 or IL-10 and TGFβ. The disparity in mTOR activation between immunogenic and tolerogenic stimuli is quantitative rather than qualitative. In both cases, mTOR activation primarily occurs through the PI3K/Akt signaling axis and involves ERK and GSK3β kinases, with minimal involvement of AMPK or NF-kB pathways. Furthermore, in the case of SSPs, mTOR activation seems to involve adenosine receptors. Additionally, we observed that DCs treated with SSPs exhibit an energy metabolism with high plasticity, which is typical of tolerogenic cells rather than immunogenic cells. Conclusion: Hence, the decision whether dendritic cells enter an inflammatory or tolerogenic state seems to rely on varying activation thresholds and kinetics of the mTOR signaling pathway. [ABSTRACT FROM AUTHOR]

Objective: Rare disease Background: Langerhans cell histiocytosis (LCH) is a rare and uncontrolled proliferation of dendritic cells of myeloid origin. The incidence of LHC was estimated at 5 cases per million children ages 0-15 years old. The most common places for this tumor are the jaw, vertebra, pelvis, and the extremities. The disease with multisystem involvement can present a mortality rate of 20% and one-third of children have multisystem involvement. We present a case with unusual bone involvement of the anterior cranial base with a challenging diagnosis and a complex surgical approach. Case Report: We report the case of a 6-year-old boy who manifested the disease with daily holocranial headache, worse in the frontal region and refractory to analgesia for 10 days, strabismus homonymous, diplopia, and right palpebral ptosis. The tumor affected the sphenoid sinus, internal carotid artery, and sella turcica, and made contact with the pituitary gland. A joint surgery with Otorhinolaryngology and Neurosurgery was performed by nasal endoscopic access to the skull base by means of the right medial turbinectomy (for the access) and right sphenoid opening, septectomy and opening of the left sphenoid to work with 4 hands and, after resection of lesion, inside the sphenoid. Conclusions: This patient had rare bone involvement from LCH and atypical clinical presentation next to the important and delicate structures of the anterior skull base, but had a satisfactory outcome. [ABSTRACT FROM AUTHOR]

Enhancing immune response activation through the synergy of effective antigen delivery and immune enhancement using natural, biodegradable materials with immune-adjuvant capabilities is challenging. Here, we present NAPSL.p that can activate the Toll-like receptor 4 (TLR4) pathway, an amphiphilic exopolysaccharide, as a potential self-assembly adjuvant delivery platform. Its molecular structure and unique properties exhibited remarkable self-assembly, forming a homogeneous nanovaccine with ovalbumin (OVA) as the model antigen. When used as an adjuvant, NAPSL.p significantly increased OVA uptake by dendritic cells. In vivo imaging revealed prolonged pharmacokinetics of NAPSL. p-delivered OVA compared to OVA alone. Notably, NAPSL.p induced elevated levels of specific serum IgG and isotype titers, enhancing rejection of B16-OVA melanoma xenografts in vaccinated mice. Additionally, NAPSL.p formulation improved therapeutic effects, inhibiting tumor growth, and increasing animal survival rates. The nanovaccine elicited CD4+ and CD8+ T cell-based immune responses, demonstrating the potential for melanoma prevention. Furthermore, NAPSL.p-based vaccination showed stronger protective effects against influenza compared to Al (OH)3 adjuvant. Our findings suggest NAPSL.p as a promising, natural self-adjuvanting delivery platform to enhance vaccine design across applications. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 73-year-old woman transferred to the hospital due to a worsening rash, following rectal pain and abnormal laboratory findings. It discusses her initial evaluation, treatment, and subsequent development of an erosive rash, highlighting the diagnostic and management challenges in such cases.

The COVID-19 pandemic has made assessing vaccine efficacy more challenging. Besides neutralizing antibody assays, systems vaccinology studies use omics technology to reveal immune response mechanisms and identify gene signatures in human peripheral blood mononuclear cells (PBMCs). However, due to their low proportion in PBMCs, profiling the immune response signatures of dendritic cells (DCs) is difficult. Here, we develop a predictive model for evaluating early immune responses in dendritic cells. We establish a THP-1-derived dendritic cell (TDDC) model and stimulate their maturation in vitro with an optimal dose of attenuated yellow fever 17D (YF-17D). Transcriptomic analysis reveals that type I interferon (IFN-I)-induced immunity plays a key role in dendritic cells. IFN-I regulatory biomarkers (IRF7, SIGLEC1) and IFN-I-inducible biomarkers (IFI27, IFI44, IFIT1, IFIT3, ISG15, MX1, OAS2, OAS3) are identified and validated in vitro and in vivo. Furthermore, we apply this TDDC approach to various types of vaccines, providing novel insights into their early immune response signatures and their heterogeneity in vaccine recipients. Our findings suggest that a standardizable TDDC model is a promising predictive approach to assessing early immunity in DCs. Further research into vaccine efficacy assessment approaches on various types of immune cells could lead to a systemic regimen for vaccine development in the future. [ABSTRACT FROM AUTHOR]

Critical illness and sepsis may cause organ failure and are recognized as mortality drivers in hospitalized patients. Neuropilin-1 (NRP-1) is a multifaceted transmembrane protein involved in the primary immune response and is expressed in immune cells such as T and dendritic cells. The soluble form of NRP-1 (sNRP-1) acts as an antagonist to NRP-1 by scavenging its ligands. The aim of this study was to determine the value of sNRP-1 as a biomarker in critical illness and sepsis. We enrolled 180 critically ill patients admitted to a medical intensive care unit and measured serum sNRP-1 concentrations at admission, comparing them to 48 healthy individuals. Critically ill and septic patients showed higher levels of sNRP-1 compared to healthy controls (median of 2.47 vs. 1.70 nmol/L, p < 0.001). Moreover, sNRP-1 was also elevated in patients with sepsis compared to other critical illness (2.60 vs. 2.13 nmol/L, p = 0.01), irrespective of disease severity or organ failure. In critically ill patients, sNRP-1 is positively correlated with markers of kidney and hepatic dysfunction. Most notably, critically ill patients not surviving in the long term (one year after admission) showed higher concentrations of sNRP-1 at the time of ICU admission (p = 0.036), with this association being dependent on the presence of organ failure. Critically ill and septic patients exhibit higher serum concentrations of circulating sNRP-1, which correlates to organ failure, particularly hepatic and kidney dysfunction. [ABSTRACT FROM AUTHOR]

Glioblastomas (GBM) are the most common primary malignant brain tumors, comprising 2% of all cancers in adults. Their location and cellular and molecular heterogeneity, along with their highly infiltrative nature, make their treatment challenging. Recently, our research group reported promising results from a prospective phase II clinical trial involving allogeneic vaccination with dendritic cells (DCs). To date, six out of the thirty-seven reported cases remain alive without tumor recurrence. In this study, we focused on the characterization of infiltrating immune cells observed at the time of surgical resection. An analytical model employing a neural network-based predictive algorithm was used to ascertain the potential prognostic implications of immunological variables on patients' overall survival. Counterintuitively, immune phenotyping of tumor-associated macrophages (TAMs) has revealed the extracellular marker PD-L1 to be a positive predictor of overall survival. In contrast, the elevated expression of CD86 within this cellular subset emerged as a negative prognostic indicator. Fundamentally, the neural network algorithm outlined here allows a prediction of the responsiveness of patients undergoing dendritic cell vaccination in terms of overall survival based on clinical parameters and the profile of infiltrated TAMs observed at the time of tumor excision. [ABSTRACT FROM AUTHOR]

Background: Chronic obstructive pulmonary disease (COPD) is characterized, at least in part, by autoimmunity through amplified T helper 1 and 17 (Th1 and Th17) immune responses. The loss of immune tolerance controlled by programmed death-ligand 1 (PD-L1) may contribute to this. Objectives: We studied the tolerogenic role of PD-L1+ dendritic cells (DCs) and their subtypes in relation to specific T cell immunity and the clinical phenotypes of COPD. Methods: We used flow cytometry to analyze PD-L1 expression by the DCs and their subtypes in the peripheral blood mononuclear cells (PBMCs) from normal participants and those with COPD. T cell proliferation and the signature cytokines of T cell subtypes stimulated with elastin as autoantigens were measured using flow cytometry and enzyme-linked immunosorbent assays (ELISA), respectively. Measurement and main results: A total of 83 participants were enrolled (normal, n = 29; COPD, n = 54). A reduced PD-L1+ conventional dendritic cell 1 (cDC1) ratio in the PBMCs of the patients with COPD was shown (13.7 ± 13.7%, p = 0.03). The decrease in the PD-L1+ cDC1 ratio was associated with a rapid decline in COPD (p = 0.02) and correlated with the CD4+ T cells (r = −0.33, p = 0.02). This is supported by the NCBI GEO database accession number GSE56766, the researchers of which found that the gene expressions of PD-L1 and CD4, but not CD8 were negatively correlated from PBMC in COPD patients (r = −0.43, p = 0.002). Functionally, the PD-L1 blockade enhanced CD4+ T cell proliferation stimulated by CD3/elastin (31.2 ± 22.3%, p = 0.04) and interleukin (IL)-17A production stimulated by both CD3 (156.3 ± 54.7, p = 0.03) and CD3/elastin (148 ± 64.9, p = 0.03) from the normal PBMCs. The PD-L1 blockade failed to increase IL-17A production in the cDC1-depleted PBMCs. By contrast, there was no significant change in interferon (IFN)-γ, IL-4, or IL-10 after the PD-L1 blockade. Again, these findings were supported by the NCBI GEO database accession number GSE56766, the researchers of which found that only the expression of RORC, a master transcription factor driving the Th17 cells, was significantly negatively correlated to PD-L1 (r = −0.33, p = 0.02). Conclusions: Circulating PD-L1+ cDC1 was reduced in the patients with COPD, and the tolerogenic role was suppressed with susceptibility to self-antigens and linked to rapid decline caused by Th17-skewed chronic inflammation. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 interferes with antigen presentation by downregulating major histocompatibility complex (MHC) II on antigen-presenting cells, but the mechanism mediating this process is unelucidated. Herein, analysis of protein and gene expression in human antigen-presenting cells reveals that MHC II is downregulated by the SARS-CoV-2 main protease, NSP5. This suppression of MHC II expression occurs via decreased expression of the MHC II regulatory protein CIITA. CIITA downregulation is independent of the proteolytic activity of NSP5, and rather, NSP5 delivers HDAC2 to the transcription factor IRF3 at an IRF-binding site within the CIITA promoter. Here, HDAC2 deacetylates and inactivates the CIITA promoter. This loss of CIITA expression prevents further expression of MHC II, with this suppression alleviated by ectopic expression of CIITA or knockdown of HDAC2. These results identify a mechanism by which SARS-CoV-2 limits MHC II expression, thereby delaying or weakening the subsequent adaptive immune response. [ABSTRACT FROM AUTHOR]

Simple Summary: Melanoma, the deadliest skin cancer, is a focus of research worldwide. This malignancy has been demonstrated to evade the immune system through several escape mechanisms. Among these, melanoma-related Dendritic Cells (DCs) alterations, particularly within the Sentinel Lymph Node (SLN), seem to play a key role. In SLNs, melanoma-related factors create a tumor microenvironment capable of impairing the immune response, inducing tolerance to tumor antigens and thus favoring SLN early metastases. The present literature review describes the interactions between Langerhans Cell (LC), a particular DC subset, and melanoma, suggesting a new potential therapeutic target. Background. Langerhans cells (LCs) are professional Dendritic Cells (DCs) involved in immunoregulatory functions. At the skin level, LCs are immature. In response to tissue injuries, they migrate to regional Lymph Nodes (LNs), reaching a full maturation state. Then, they become effective antigen-presenting cells (APCs) that induce anti-cancer responses. Notably, melanoma patients present several DC alterations in the Sentinel Lymph Node (SLN), where primary antitumoral immunity is generated. LCs are the most represented DCs subset in melanoma SLNs and are expected to play a key role in the anti-melanoma response. With this paper, we aim to review the current knowledge and future perspectives regarding LCs and melanoma. Methods. A systematic review was carried out according to the PRISMA statement using the PubMed (MEDLINE) library from January 2004 to January 2024, searching for original studies discussing LC in melanoma. Results. The final synthesis included 15 articles. Several papers revealed significant LCs–melanoma interactions. Conclusions. Melanoma immune escape mechanisms include SLN LC alterations, favoring LN metastasis arrival/homing and melanoma proliferation. The SLN LCs of melanoma patients are defective but not irreversibly, and their function may be restored by appropriate stimuli. Thus, LCs represent a promising target for future immunotherapeutic strategies and cancer vaccines. [ABSTRACT FROM AUTHOR]

Simple Summary: Since TIM-3 on T cells or dendritic cells (DCs) has recently emerged as an attractive target for immunotherapy, we examined its expression on DCs using transcriptomic data from a public database and immunohistochemical evaluations from our cohorts of colorectal cancer. The expression of HAVCR2 (TIM-3) was strongly associated with the infiltration of DCs within the tumor microenvironment, and immunohistochemical staining of clinical tissue samples revealed that tumor-infiltrating DCs expressed TIM-3; however, their number at the tumor-invasive front significantly decreased with stage progression. Among vitro-generated DCs, TIM-3 expression was higher on immature DCs than on mature DCs, while Western blotting showed that STING expression was higher on mature DCs than on immature DCs. TIM-3 was originally identified as a negative regulator of helper T cells and is expressed on dendritic cells (DCs). Since the inhibition of TIM-3 on DCs has been suggested to enhance T cell-mediated anti-tumor immunity, we examined its expression on DCs within the tumor microenvironment (TME) in colorectal cancer (CRC) using transcriptomic data from a public database (n = 592) and immunohistochemical evaluations from our cohorts of CRC (n = 115). The expression of TIM-3 on DCs in vitro was examined by flow cytometry, while the expression of its related molecules, cGAS and STING, on immature and mature DCs was assessed by Western blotting. The expression of HAVCR2 (TIM-3) was strongly associated with the infiltration of DCs within the TME of CRC. Immunohistochemical staining of clinical tissue samples revealed that tumor-infiltrating DCs expressed TIM-3; however, their number at the tumor-invasive front significantly decreased with stage progression. TIM-3 expression was higher on immature DCs than on mature DCs from several different donors (n = 6). Western blot analyses showed that the expression of STING was higher on mature DCs than on immature DCs, which was opposite to that of TIM-3. We demonstrated that TIM-3 was highly expressed on tumor-infiltrating DCs of CRC and that its expression was higher on immature DCs than on mature DCs. [ABSTRACT FROM AUTHOR]

Crosstalk between dendritic cells and T cells plays a crucial role in modulating immune responses in natural and pathological conditions. DC-T cell crosstalk is achieved through contact-dependent (i.e., immunological synapse) and contact-independent mechanisms (i.e., cytokines). Activated DCs upregulate co-stimulatory signals and secrete proinflammatory cytokines to orchestrate T cell activation and differentiation. Conversely, activated T helper cells "license" DCs towards maturation, while regulatory T cells (Tregs) silence DCs to elicit tolerogenic immunity. Strategies to efficiently modulate the DC-T cell crosstalk can be harnessed to promote immune activation for cancer immunotherapy or immune tolerance for the treatment of autoimmune diseases. Here, we review the natural crosstalk mechanisms between DC and T cells. We highlight bioengineering approaches to modulate DC-T cell crosstalk, including conventional vaccines, synthetic vaccines, and DC-mimics, and key seminal studies leveraging these approaches to steer immune response for the treatment of cancer and autoimmune diseases. [ABSTRACT FROM AUTHOR]

Glycans on tumor cell surface have significant impacts in the immune‐killing process. Here an ultra‐galactocation to sialic acid (Sia) strategy is designed to hugely introduce galactose (Gal) to Sia and on tumor cells in vivo by using a penta‐functional dendritic probe (Den@5F), which efficiently enhances the immune‐killing of tumor cells. The Den@5F contains five different kinds of functional groups, including Gal, Cy5, amino, phenylboronic acid (PBA) and 4‐(4‐(hydroxymethyl)‐2‐methoxy‐5‐nitrophenoxy) butanoate (mNB), which can be conveniently prepared through a two‐step reaction. After injecting into the tumor‐bearing mouse, Den@5F can efficiently block Sia through the specific recognition between PBA and Sia on tumor cells and hugely introduce Gal through the subsequent photo‐crosslinking between mNB and amino groups to multiply conjugate excessive Den@5Fs. The comprehensively blocked Sia can prevent the immune escape, and the hugely introduced Gal can promote the immune stimulation of the immune cells, which lead to an efficient enhancement of the immune‐killing. The proposed strategy provides a significant and promising tool to promote the clinical immunotherapy of tumor. [ABSTRACT FROM AUTHOR]

Glycans on tumor cell surface have significant impacts in the immune‐killing process. Here an ultra‐galactocation to sialic acid (Sia) strategy is designed to hugely introduce galactose (Gal) to Sia and on tumor cells in vivo by using a penta‐functional dendritic probe (Den@5F), which efficiently enhances the immune‐killing of tumor cells. The Den@5F contains five different kinds of functional groups, including Gal, Cy5, amino, phenylboronic acid (PBA) and 4‐(4‐(hydroxymethyl)‐2‐methoxy‐5‐nitrophenoxy) butanoate (mNB), which can be conveniently prepared through a two‐step reaction. After injecting into the tumor‐bearing mouse, Den@5F can efficiently block Sia through the specific recognition between PBA and Sia on tumor cells and hugely introduce Gal through the subsequent photo‐crosslinking between mNB and amino groups to multiply conjugate excessive Den@5Fs. The comprehensively blocked Sia can prevent the immune escape, and the hugely introduced Gal can promote the immune stimulation of the immune cells, which lead to an efficient enhancement of the immune‐killing. The proposed strategy provides a significant and promising tool to promote the clinical immunotherapy of tumor. [ABSTRACT FROM AUTHOR]

The lack of broad‐spectrum tumor antigens, limited immunogenicity of antigens, and immunosuppressive microenvironment in tumors have impeded the development of cancer vaccines. To address this issue, a vaccine platform is developed based on Spirulina skeleton fibers loaded with gold (Au) nanoparticles (Au@E‐SP). Upon subcutaneous administration, Au@E‐SP self‐aggregates in situ and forms a 3D vaccine scaffold owing to its elongated and helical architecture. Through the aggregation of Au@E‐SP, Au nanoparticles are concentrated, which significantly enhances the local photothermal effect and releases more tumor‐associated antigens. In addition, the retained E‐SP serves as a natural immune adjuvant that sustainably reverses the immunosuppressive microenvironment in vivo. Combining these advantages, the vaccines induce a potent anti‐tumor immune response, effectively inhibiting tumor recurrence and metastasis. This strategy utilizes microalgae as a self‐adjuvant vaccine, providing a promising avenue for further research in tumor immunotherapy. [ABSTRACT FROM AUTHOR]

Background: Cancer is the leading cause of death among older adults. Although the integration of immunotherapy has revolutionized the therapeutic landscape of cancer, the complex interactions between age and immunotherapy efficacy remain incompletely defined. Here, we aimed to elucidate the relationship between aging and immunotherapy resistance. Methods: Flow cytometry was performed to evaluate the infiltration of immune cells in the tumor microenvironment (TME). In vivo T cell proliferation, cytotoxicity and migration assays were performed to evaluate the antitumor capacity of tumor antigen-specific CD8+ T cells in mice. Real-time quantitative PCR (qPCR) was used to investigate the expression of IFN-γ-associated gene and natural killer (NK)-associated chemokine. Adoptive NK cell transfer was adopted to evaluate the effects of NK cells from young mice in overcoming the immunotherapy resistance of aged mice. Results: We found that elderly patients with advanced non-small cell lung cancer (aNSCLC) aged ≥ 75 years exhibited poorer progression-free survival (PFS), overall survival (OS) and a lower clinical response rate after immunotherapy. Mechanistically, we showed that the infiltration of NK cells was significantly reduced in aged mice compared to younger mice. Furthermore, the aged NK cells could also suppress the activation of tumor antigen-specific CD8+ T cells by inhibiting the recruitment and activation of CD103+ dendritic cells (DCs). Adoptive transfer of NK cells from young mice to aged mice promoted TME remodeling, and reversed immunotherapy resistance. Conclusion: Our findings revealed the decreased sensitivity of elderly patients to immunotherapy, as well as in aged mice. This may be attributed to the reduction of NK cells in aged mice, which inhibits CD103+ DCs recruitment and its CD86 expression and ultimately leads to immunotherapy resistance. [ABSTRACT FROM AUTHOR]

Gene editing of living cells has become a crucial tool in medical research, enabling scientists to address fundamental biological questions and develop novel strategies for disease treatment. This technology has particularly revolutionized adoptive transfer cell therapy products, leading to significant advancements in tumor treatment and offering promising outcomes in managing transplant rejection, autoimmune disorders, and inflammatory diseases. While recent clinical trials have demonstrated the safety of tolerogenic dendritic cell (TolDC) immunotherapy, concerns remain regarding its effectiveness. This review aims to discuss the application of gene editing techniques to enhance the tolerance function of dendritic cells (DCs), with a particular focus on preclinical strategies that are currently being investigated to optimize the tolerogenic phenotype and function of DCs. We explore potential approaches for in vitro generation of TolDCs and provide an overview of emerging strategies for modifying DCs. Additionally, we highlight the primary challenges hindering the clinical adoption of TolDC therapeutics and propose future research directions in this field. [ABSTRACT FROM AUTHOR]