Inflammatory Immune Microenvironment Research Articles

A Microenvironment-Responsive, Controlled Release Hydrogel Delivering Embelin to Promote Bone Repair of Periodontitis via Anti-Infection and Osteo-Immune Modulation.

Periodontitis, a prevalent chronic inflammatory disease, poses significant challenges for effective treatment due to its complex etiology involving specific bacteria and the inflammatory immune microenvironment. Here, this study presents a novel approach for the targeted treatment of periodontitis utilizing the immunomodulatory and antibacterial properties of Embelin, a plant-derived compound, within an injectable hydrogel system. The developed Carboxymethyl Chitosan-Oxidized Dextran (CMCS-OD) hydrogel formed via dynamic chemical bonds exhibited self-healing capabilities and pH-responsive behavior, thereby facilitating the controlled release of Embelin and enhancing its efficacy in a dynamic oral periodontitis microenvironment. This study demonstrates that this hydrogel system effectively prevents bacterial invasion and mitigates excessive immune response activation. Moreover, it precisely modulates macrophage M1/M2 phenotypes and suppresses inflammatory cytokine expression, thereby fostering a conducive environment for bone regeneration and addressing periodontitis-induced bone loss. These findings highlight the potential of the approach as a promising strategy for the clinical management of periodontitis-induced bone destruction.

Pyroptosis mediates osteoporosis via the inflammation immune microenvironment.

Osteoporosis represents a systemic imbalance in bone metabolism, augmenting the susceptibility to fractures among patients and emerging as a notable mortality determinant in the elderly population. It has evolved into a worldwide concern impacting the physical well-being of the elderly, imposing a substantial burden on both human society and the economy. Presently, the precise pathogenesis of osteoporosis remains inadequately characterized and necessitates further exploration. The advancement of osteoporosis is typically linked to the initiation of an inflammatory response. Cells in an inflammatory environment can cause inflammatory death including pyroptosis. Pyroptosis is a recently identified form of programmed cell death with inflammatory properties, mediated by the caspase and gasdermin families. It is regarded as the most inflammatory form of cell death in contemporary medical research. Under the influence of diverse cytokines, macrophages, and other immune cells may undergo pyroptosis, releasing inflammatory factors, such as IL-1β and IL-18. Numerous lines of evidence highlight the pivotal role of pyroptosis in the pathogenesis of inflammatory diseases, including cancer, intestinal disorders, hepatic conditions, and cutaneous ailments. Osteoporosis progression is frequently associated with inflammation; hence, pyroptosis may also play a role in the pathogenesis of osteoporosis to a certain extent, making it a potential target for treatment. This paper has provided a comprehensive summary of pertinent research concerning pyroptosis and its impact on osteoporosis. The notion proposing that pyroptosis mediates osteoporosis via the inflammatory immune microenvironment is advanced, and we subsequently investigate potential targets for treating osteoporosis through the modulation of pyroptosis.

Alleviating lung injury and pulmonary fibrosis in radiotherapy-immunotherapy combination: The role of low-dose radiation therapy.

e14632 Background: Lung cancer continues to be the primary cause of cancer-related mortality on a global scale. The integration of radiotherapy and immunotherapy has yielded significant advancements in the treatment of locally advanced non-small cell lung cancer. However, the occurrence of treatment-associated pneumonia remains the predominant adverse event necessitating treatment cessation and permanent medication discontinuation. The immune-modulating effects of radiation therapy on the body contribute to a complex interplay between radiation and inflammation. Low-dose radiotherapy (LD-RT) has historically been utilized for the management of benign inflammatory conditions. Recently, LD-RT was found to be effective in treating severe pneumonia in patients with severe COVID-19 as well as acute respiratory distress syndrome (ARDS). This investigation seeks to examine the impact of LD-RT on lung tissue morphology and the inflammatory immune microenvironment in preclinical models of lung injury induced by high-dose radiotherapy combined with programmed death-1(PD-1) inhibitor therapy. Methods: 6-8 week old C57BL/6 mice were treated with a single high-dose thoracic radiotherapy (15Gy) and the PD-1 inhibitor (once a week), with or without the low-dose radiotherapy (1.0/1.5Gy) four weeks later. Lung tissue was collected one and a half months and three months respectively after the initial high-dose radiotherapy for evaluation using HE and Masson staining, Image J software for analysis of collagen volume fraction (CVF), and immunohistochemical staining for CD3+ and CD8+ T lymphocytes. Cytokine transforming growth factor (TGF)-β1、interleukin (IL)-6 and tumor necrosis factor (TNF)-α level in lung tissue was detected by ELISA. Statistical analysis was performed using GraphPad Prism 9.5.0 software. Results: The radiotherapy-immunotherapy combination (iRT) group exhibits notable lung injury characterized by the proliferation of alveolar type II epithelial cells, thickening of alveolar septa, interstitial edema, pulmonary congestion and bleeding, increased infiltration of inflammatory cells, and significant deposition of interstitial collagen fibers. In contrast, the iRT+ LD-RT group demonstrates a significant decrease in lung tissue damage, interstitial fibrosis, collagen volume fraction (CVF), levels of IL-6 and TGF-β, as well as the infiltration of CD3+ and CD8+T cells compared to the iRT group. Conclusions: Low-dose radiation has the potential to ameliorate lung injury induced by the combination of radiotherapy and PD-1 inhibitors by modulating the inflammatory milieu, thereby potentially mitigating the development of pulmonary fibrosis.

A Thermosensitive Hydrogel with Efficient NIR Photothermal Conversion as Injectable Wound Dressing for Accelerating Skin Wound Healing

AbstractBacterial infection at wound sites can easily induce robust inflammation. M1 macrophages at wound sites can cause cascade inflammatory reactions to mediate a vicious inflammation cycle. Meanwhile, the hypoxia situation further aggravates the destruction and contraction of blood vessels in the wound microenvironment, therefore, hindering the infected wound healing process. Here, a thermosensitive hydrogel is reported to solve the above challenges by eliminating bacteria based on the photothermal effect, regulating the inflammatory immune microenvironment, and providing oxygen (O2). In vitro and in vivo experiments confirmed that the hydrogel has great O2‐producing properties. Based on the excellent photothermal properties of AIEgens, the hydrogel has a good bactericidal effect against S. aureus (100%) and E. coli (98.85%). The RNA‐sequencing revealed that Cur@AIE@MnO2/gel can interfere with the metabolic process and genetic material repair process to impact bacteria proliferation and biofilm dispersal, thus achieving excellent anti‐bacterial efficacy. Moreover, Cur@AIE@MnO2/gel can also up‐regulate anti‐inflammatory genes, down‐regulate pro‐inflammatory genes in macrophages, and facilitate the promotion of macrophage polarization from M1 to M2 to relieve inflammation. The therapeutic experiments show that this hydrogel accelerated the wound‐healing process. Therefore, this work may open new avenues for the development of novel dressings for bacterial‐infected wounds.

Gasdermins: a dual role in pyroptosis and tumor immunity.

The gasdermin (GSDM) protein family plays a pivotal role in pyroptosis, a process critical to the body's immune response, particularly in combatting bacterial infections, impeding tumor invasion, and contributing to the pathogenesis of various inflammatory diseases. These proteins are adept at activating inflammasome signaling pathways, recruiting immune effector cells, creating an inflammatory immune microenvironment, and initiating pyroptosis. This article serves as an introduction to the GSDM protein-mediated pyroptosis signaling pathways, providing an overview of GSDMs' involvement in tumor immunity. Additionally, we explore the potential applications of GSDMs in both innovative and established antitumor strategies.

An Engineered Bionic Nanoparticle Sponge as a Cytokine Trap and Reactive Oxygen Species Scavenger to Relieve Disc Degeneration and Discogenic Pain.

The progressive worsening of disc degeneration and related nonspecific back pain are prominent clinical issues that cause a tremendous economic burden. Activation of reactive oxygen species (ROS) related inflammation is a primary pathophysiologic change in degenerative disc lesions. This pathological state is associated with M1 macrophages, apoptosis of nucleus pulposus cells (NPC), and the ingrowth of pain-related sensory nerves. To address the pathological issues of disc degeneration and discogenic pain, we developed MnO2@TMNP, a nanomaterial that encapsulated MnO2 nanoparticles with a TrkA-overexpressed macrophage cell membrane (TMNP). Consequently, this engineered nanomaterial showed high efficiency in binding various inflammatory factors and nerve growth factors, which inhibited inflammation-induced NPC apoptosis, matrix degradation, and nerve ingrowth. Furthermore, the macrophage cell membrane provided specific targeting to macrophages for the delivery of MnO2 nanoparticles. MnO2 nanoparticles in macrophages effectively scavenged intracellular ROS and prevented M1 polarization. Supportively, we found that MnO2@TMNP prevented disc inflammation and promoted matrix regeneration, leading to downregulated disc degenerative grades in the rat injured disc model. Both mechanical and thermal hyperalgesia were alleviated by MnO2@TMNP, which was attributed to the reduced calcitonin gene-related peptide (CGRP) and substance P expression in the dorsal root ganglion and the downregulated Glial Fibrillary Acidic Protein (GFAP) and Fos Proto-Oncogene (c-FOS) signaling in the spinal cord. We confirmed that the MnO2@TMNP nanomaterial alleviated the inflammatory immune microenvironment of intervertebral discs and the progression of disc degeneration, resulting in relieved discogenic pain.

Role and mechanism of macrophage-mediated osteoimmune in osteonecrosis of the femoral head

To summarize the research progress on the role of macrophage-mediated osteoimmune in osteonecrosis of the femoral head (ONFH) and its mechanisms. Recent studies on the role and mechanism of macrophage-mediated osteoimmune in ONFH at home and abroad were extensively reviewed. The classification and function of macrophages were summarized, the osteoimmune regulation of macrophages on chronic inflammation in ONFH was summarized, and the pathophysiological mechanism of osteonecrosis was expounded from the perspective of osteoimmune, which provided new ideas for the treatment of ONFH. Macrophages are important immune cells involved in inflammatory response, which can differentiate into classically activated type (M1) and alternatively activated type (M2), and play specific functions to participate in and regulate the physiological and pathological processes of the body. Studies have shown that bone immune imbalance mediated by macrophages can cause local chronic inflammation and lead to the occurrence and development of ONFH. Therefore, regulating macrophage polarization is a potential ONFH treatment strategy. In chronic inflammatory microenvironment, inhibiting macrophage polarization to M1 can promote local inflammatory dissipation and effectively delay the progression of ONFH; regulating macrophage polarization to M2 can build a local osteoimmune microenvironment conducive to bone repair, which is helpful to necrotic tissue regeneration and repair to a certain extent. At present, it has been confirmed that macrophage-mediated chronic inflammatory immune microenvironment is an important mechanism for the occurrence and development of ONFH. It is necessary to study the subtypes of immune cells in ONFH, the interaction between immune cells and macrophages, and the interaction between various immune cells and macrophages, which is beneficial to the development of potential therapeutic methods for ONFH.

Remodeling periodontal osteoimmune microenvironment through MAPK/NFκB phosphorylation pathway of macrophage via intelligent ROS scavenging.

Periodontitis is an inflammatory disorder which leads to the defect of tooth-supporting tissue, especially in alveolar bone. During this process, the polarization behavior of macrophages affects immune inflammation and bone regeneration in which reactive oxygen species (ROS) play an essential role. ROS level should be regulated to the physiological level to protect stem cells from the inflammatory immune microenvironment. Our previous study constructed a ROS-responsive nanoplatform (Pssl-NAC), which possessed ROS-responsive antioxidative effect and could be potentially applied in periodontitis. However, the connection among bone regeneration, inflammation and oxidative stress remained in osteoimmune regulation is not clear. To further investigate the mechanism of the way how Pssl-NAC works in the treatment of periodontitis would be meaningful. Here, we investigated the effect of PssL-NAC in the regulation of the osteoimmune microenvironment through macrophage polarization. Results show PssL-NAC regulated the macrophage polarization direction in an inflammatory environment by maintaining an appropriate level of intracellular ROS, in which the MAPK/NFκB phosphorylation pathway is particularly important. In the macrophage-human periodontal ligament stem cells (hPDLSCs) co-culture system, PssL-NAC treatment significantly enhanced the osteogenic differentiation of hPDLSCs. In vivo experiment further confirmed the M2-like macrophages increased in the periodontal tissue of rats, and the expression of iNOS and p65 decreased after PssL-NAC treatment. In conclusion, PssL-NAC regulates the osteoimmune microenvironment and protects stem cells from oxidative stress injury for bone regeneration, which provides a strategy for the treatment of periodontitis.

2-DG Regulates Immune Imbalance on the Titanium Surface after Debridement.

Peri-implantitis requires clinical treatments comprised of mechanical and chemical debridement to remove bacterial biofilms. Bone regeneration on the titanium surface after debridement has been a topical issue of peri-implantitis treatments. Increasing evidence has revealed that the immune microenvironment plays a key role in regulating the bone regeneration process. However, it remains unclear what kind of immune microenvironment the titanium surface induces after debridement. In the study, model titanium surface after debridement was prepared via biofilm induction and mechanical and chemical debridement in vitro. Then, the macrophages and naïve CD4+ T lymphocytes were cultured on the titanium surface after debridement for immune microenvironment evaluation, with the original titanium surface as the control. Next, to regulate the immune microenvironment, 2-DG, a glycolysis inhibitor, was further incorporated to regulate macrophages and CD4+ T lymphocytes at the same time. Surface characterization results showed that the bacterial biofilms were completely removed, while the micro-morphology of titanium surface altered after debridement, and the element composition did not change. Compared with the original titanium disc, titanium surface after debridement can lead to the inflammatory differentiation of macrophages and CD4+ T lymphocytes. The percentage of M1 and Th17 inflammatory cells and the expression of their inflammatory factor genes are upregulated. However, 0.3 mmol of 2-DG can significantly reduce the inflammatory differentiation of both macrophages and CD4+ T lymphocytes and inhibit their expression of inflammatory genes. In conclusion, although bacterial biofilms were removed from titanium surface after debridement, the surface topography changes could still induce immune imbalance and form an inflammatory immune microenvironment. However, this inflammatory immune microenvironment can be effectively reversed by 2-DG in vitro, thus creating an immune microenvironment conducive to osteogenesis, which might provide a new perspective for future therapy of peri-implantitis.

An immune and epithelial-mesenchymal transition-related risk model and immunotherapy strategy for grade II and III gliomas.

Grade II and III gliomas are heterogeneous and aggressive diseases. More efficient prognosis models and treatment methods are needed. This study aims to construct a new risk model and propose a new strategy for grade II and III gliomas. The data were downloaded from The Cancer Genome Atlas (TCGA), the Gene Expression Omnibus (GEO), gene set enrichment analysis (GSEA), and the EMTome website for analysis. The Human Cell Landscape website and the Genomics of Drug Sensitivity in Cancer website were used for single-cell analysis and drug susceptibility analysis. Gene set enrichment analysis, gene function enrichment analysis, univariate and multivariate Cox regression analyses, Pearson's correlation analysis, log-rank test, Kaplan-Meier survival analysis, and ROC analysis were performed. We constructed an immune-related prognostic model associated with the isocitrate dehydrogenase 1 (IDH1) mutation status. By analyzing the immune microenvironment of patients with different risk scores, we found that high-risk patients were more likely to have an inflammatory immune microenvironment and a higher programmed death ligand-1 (PD-L1) expression level. Epithelial-mesenchymal transition (EMT)-related gene sets were significantly enriched in the high-risk group, and the epithelial-mesenchymal transition phenotype was associated with a decrease in CD8+ T cells and an increase in M2 macrophages. Transforming growth factor-β (TGF-β) signaling was the most important signaling in inducing epithelial-mesenchymal transition, and TGFB1/TGFBR1 was correlated with an increase in CD8+ T cytopenia and M2 macrophages. Survival analysis showed that simultaneous low expression of TGFBR1 and PD-L1 had better survival results. Through single-cell analysis, we found that TGFB1 is closely related to microglia and macrophages, especially M2 macrophages. Finally, we discussed the sensitivity of TGFB1 inhibitors in gliomas using cell line susceptibility data. These results demonstrated a potential immunotherapy strategy in combination with the TGFB1/TGFBR1 inhibitor and PD-1/PD-L1 inhibitor for grade II and III gliomas.

Low-intensity pulsed ultrasound promotes skeletal muscle regeneration via modulating the inflammatory immune microenvironment.

Background: Low-intensity pulsed ultrasound (LIPUS, a form of mechanical stimulation) can promote skeletal muscle functional repair, but a lack of mechanistic understanding of its relationship and tissue regeneration limits progress in this field. We investigated the hypothesis that specific energy levels of LIPUS mediates skeletal muscle regeneration by modulating the inflammatory microenvironment. Methods: To address these gaps, LIPUS irritation was applied in vivo for 5 min at two different intensities (30mW/cm2 and 60mW/cm2) in next 7 consecutive days, and the treatment begun at 24h after air drop-induced contusion injury. In vitro experiments, LIPUS irritation was applied at three different intensities (30mW/cm2, 45mW/cm2, and 60mW/cm2) for 2 times 24h after introduction of LPS in RAW264.7. Then, we comprehensively assessed the functional and histological parameters of skeletal muscle injury in mice and the phenotype shifting in macrophages through molecular biological methods and immunofluorescence analysis both in vivo and in vitro. Results: We reported that LIPUS therapy at intensity of 60mW/cm2 exhibited the most significant differences in functional recovery of contusion-injured muscle in mice. The comprehensive functional tests and histological analysis in vivo indirectly and directly proved the effectiveness of LIPUS for muscle recovery. Through biological methods and immunofluorescence analysis both in vivo and in vitro, we found that this improvement was attributable in part to the clearance of M1 macrophages populations and the increase in M2 subtypes with the change of macrophage-mediated factors. Depletion of macrophages in vivo eliminated the therapeutic effects of LIPUS, indicating that improvement in muscle function was the result of M2-shifted macrophage polarization. Moreover, the M2-inducing effects of LIPUS were proved partially through the WNT pathway by upregulating FZD5 expression and enhancing β-catenin nuclear translocation in macrophages both in vitro and in vivo. The inhibition and augment of WNT pathway in vitro further verified our results. Conclusion: LIPUS at intensity of 60mW/cm2 could significantly promoted skeletal muscle regeneration through shifting macrophage phenotype from M1 to M2. The ability of LIPUS to direct macrophage polarization may be a beneficial target in the clinical treatment of many injuries and inflammatory diseases.

Identification of the immune subtype of ovarian cancer patients by integrated analyses of transcriptome and single-cell sequencing data

Ovarian cancer (OC) is one the most life-threatening cancers affecting women’s health worldwide. Immunotherapy has become a promising treatment for a variety of cancers, but the therapeutic effects in OC remain limited. In this study, we constructed a macrophage risk score (MRS) based on M1 and M2 macrophages and a gene risk score (GRS) based on the prognostic genes associated with MRS. Next, cell–cell communication analysis was performed using single-cell RNA (scRNA) sequencing data. Survival status and immune characteristics were compared between the high- and low-score groups separated by MRS or GRS. Our results suggested that MRS and GRS can identify the immune subtypes of OC patients with better overall survival (OS) and inflammatory immune microenvironment. Moreover, M1 and M2 macrophages may affect the prognosis of OC patients through signal communication with CD8 T cells. Finally, functional differences between the two groups separated by GRS were elucidated. Taken together, this study constructed two useful models for the identification of immune subtypes in OC, which has a better prognosis and may have a sensitive response to immune checkpoint inhibitors (ICIs). The hub genes for the construction of GRS may be potential synergetic targets for immunotherapy in OC patients.

Multi-Omics Integration Reveals the Crucial Role of Fusobacterium in the Inflammatory Immune Microenvironment in Head and Neck Squamous Cell Carcinoma.

ABSTRACTThe tumor microbiome is believed to have a profound impact on tumor progression owing to its local colonization in the tumor microenvironment (TME). Using the Cancer Microbiome Atlas (TCMA), a database of curated, decontaminated microbial profiles for 3,689 oropharyngeal, esophageal, gastrointestinal, and colorectal tissue samples from 1,772 patients, we conducted a comprehensive multi-omics analysis to reveal microbial signatures among various cancers and the potential mechanisms involved in tumor progression of head and neck squamous cell carcinoma (HNSC). We found that compared with other cancer types, the tumor-resident microbiome of HNSC accounted for the highest bacterial abundance and strongest association with host TME signatures. Fusobacterium was found to be enriched in HNSC tissues, which was associated with an increased inflammatory effect and inferior prognosis. Moreover, we revealed that the microbiota-associated inflammatory TME was attributed to the competing endogenouse RNA (ceRNA) network and chromatin accessibility.IMPORTANCE Studies on revealing the composition and potential mechanisms of the tumor microbiome are still at an initial stage. We uncovered the potential contribution of the tumor-resident microbiota on the immunosuppressive microenvironment in HNSC, which will provide a new perspective for tumor microbiome research and yield valuable insights into the clinical management of HNSC.

Immune translational control by CPEB4 regulates intestinal inflammation resolution and colorectal cancer development

SummaryUpon tissue injury, cytokine expression reprogramming transiently remodels the inflammatory immune microenvironment to activate repair processes and subsequently return to homeostasis. However, chronic inflammation induces permanent changes in cytokine production which exacerbate tissue damage and may even favor tumor development. Here, we address the contribution of post-transcriptional regulation, by the RNA-binding protein CPEB4, to intestinal immune homeostasis and its role in inflammatory bowel diseases (IBD) and colorectal cancer (CRC) development. We found that intestinal damage induces CPEB4 expression in adaptive and innate immune cells, which is required for the translation of cytokine mRNA(s) such as the one encoding interleukin-22. Accordingly, CPEB4 is required for the development of gut-associated lymphoid tissues and to maintain intestinal immune homeostasis, mediating repair and remodeling after acute inflammatory tissue damage and promoting the resolution of intestinal inflammation. CPEB4 is chronically overexpressed in inflammatory cells in patients with IBD and in CRC, favoring tumor development.

Comprehensive Analysis of the Immune Microenvironment in Checkpoint Inhibitor Pneumonitis

BackgroundWhile immune checkpoint inhibitors (ICIs) are a beacon of hope for non-small cell lung cancer (NSCLC) patients, they can also cause adverse events, including checkpoint inhibitor pneumonitis (CIP). Research shows that the inflammatory immune microenvironment plays a vital role in the development of CIP. However, the role of the immune microenvironment (IME) in CIP is still unclear.MethodsWe collected a cohort of NSCLC patients treated with ICIs that included eight individuals with CIP (CIP group) and 29 individuals without CIP (Control group). CIBERSORT and the xCell algorithm were used to evaluate the proportion of immune cells. Gene set enrichment analysis (GSEA) and single-sample GSEA (ssGSEA) were used to evaluate pathway activity. The ridge regression algorithm was used to analyze drug sensitivity.ResultsCIBERSORT showed significantly upregulated memory B cells, CD8+ T cells, and M1 Macrophages in the CIP group. The number of memory resting CD4+ T cells and resting NK cells in the CIP group was also significantly lower than in the Control group. The XCell analysis showed a higher proportion of Class-switched memory B-cells and M1 Macrophages in the CIP group. Pathway analysis showed that the CIP group had high activity in their immune and inflammatory response pathways and low activity in their immune exhaustion related pathway.ConclusionsIn this study, we researched CIP patients who after ICIs treatment developed an inflammatory IME, which is characterized by significantly increased activated immune cells and expression of inflammatory molecules, as well as downregulated immunosuppressive lymphocytes and signaling pathways. The goal was to develop theoretical guidance for clinical guidelines for the treatment of CIP in the future.

Targeted therapy of atherosclerosis by zeolitic imidazolate framework-8 nanoparticles loaded with losartan potassium via simultaneous lipid-scavenging and anti-inflammation.

Atherosclerosis (AS) is a condition associated with dysfunctional lipid metabolism and an inflammatory immune microenvironment that remains the leading cause of severe cardiovascular events. Drugs exhibiting both anti-inflammatory and lipid-scavenging activity hold great promise for treating AS. In this study, zeolitic imidazolate framework-8 (ZIF-8) nanoparticles loaded with losartan potassium (LP) were developed as an anti-AS treatment to target both of these therapeutic arms simultaneously. LP@ZIF-8 accumulated within AS target tissues via the enhanced permeability and retention (EPR) effect, as confirmed via in vivo near-infrared fluorescence (NIRF) imaging and wasdisruptedin response tothe low pH. ZIF-8 could activate autophagy, thus regulatinglipid metabolism and restoringcholesterol homeostasis aspreviously reported, while thereleasedLPservedas an anti-inflammatory angiotensin receptor blocker (ARB) inhibitor, which was confirmed via the in vivo treatment studies. As such, our data highlight LP@ZIF-8 as a promising therapeutic agent capable of attenuating the severity of AS.

Harnessing Tissue-derived Extracellular Vesicles for Osteoarthritis Theranostics.

Osteoarthritis (OA) is a prevalent chronic whole-joint disease characterized by low-grade systemic inflammation, degeneration of joint-related tissues such as articular cartilage, and alteration of bone structures that can eventually lead to disability. Emerging evidence has indicated that synovium or articular cartilage-secreted extracellular vesicles (EVs) contribute to OA pathogenesis and physiology, including transporting and enhancing the production of inflammatory mediators and cartilage degrading proteinases. Bioactive components of EVs are known to play a role in OA include microRNA, long non-coding RNA, and proteins. Thus, OA tissues-derived EVs can be used in combination with advanced nanomaterial-based biosensors for the diagnostic assessment of OA progression. Alternatively, mesenchymal stem cell- or platelet-rich plasma-derived EVs (MSC-EVs or PRP-EVs) have high therapeutic value for treating OA, such as suppressing the inflammatory immune microenvironment, which is often enriched by pro-inflammatory immune cells and cytokines that reduce chondrocytes apoptosis. Moreover, those EVs can be modified or incorporated into biomaterials for enhanced targeting and prolonged retention to treat OA effectively. In this review, we explore recently reported OA-related pathological biomarkers from OA joint tissue-derived EVs and discuss the possibility of current biosensors for detecting EVs and EV-related OA biomarkers. We summarize the applications of MSC-EVs and PRP-EVs and discuss their limitations for cartilage regeneration and alleviating OA symptoms. Additionally, we identify advanced therapeutic strategies, including engineered EVs and applying biomaterials to increase the efficacy of EV-based OA therapies. Finally, we provide our perspective on the future of EV-related diagnosis and therapeutic potential for OA treatment.

The Impact of NOTCH Pathway Alteration on Tumor Microenvironment and Clinical Survival of Immune Checkpoint Inhibitors in NSCLC.

The treatment of non-small cell lung cancer (NSCLC) with immune checkpoint inhibitors (ICIs) has been proven to induce lasting tumor remission. Screening suitable populations for immunotherapy through predictive markers is an important approach to improving the clinical benefits of patients. Evidence has shown that there may be a close connection between NOTCH signaling and the tumor microenvironment (TME). Hence, we explored the impact of the mutation status of NOTCH signaling on the prognosis of NSCLC patients treated with immunotherapy with the aim to apply NSCLC immunotherapy to the greatest extent possible. We examined two clinical cohorts of NSCLC patients receiving ICIs (MSKCC and NG cohorts). The mutation and prognostic data of the ICI-treated cohort were used to evaluate the association between the mutation status of NOTCH signaling and prognosis following immunotherapy. The expression and mutation data of The Cancer Genome Atlas (TCGA)-NSCLC cohort were used to analyze the differences in the immune microenvironment under different NOTCH signaling mutation states. In the ICI-treated cohorts, the univariate and multivariate Cox regression analyses indicated that high-mutated NOTCH signaling could serve as an independent predictor of NSCLC patients receiving ICIs. Patients with high-mutated NOTCH signaling had significantly improved progression-free survival (PFS) (P = 0.03, HR = 0.69; MSKCC cohort) and prolonged overall survival (OS) (P = 0.004, HR = 0.34; NG cohort). Additionally, high-mutated NOTCH signaling was related to the inflammatory immune microenvironment, inflammatory expression profile, and enhanced immunogenicity. According to this study, high-mutated NOTCH signaling may serve as a biomarker for the prediction of the prognosis of NSCLC patients treated with ICIs. A series of prospective clinical studies and molecular mechanism explorations are still needed in the future.

Dendritic Cells Subsets Profiles in Classical Hodgkin Lymphoma at Diagnosis and upon Treatment Completion: Analysis on 54 Patients

Background: In Hodgkin Lymphoma (cHL) tissues a few neoplastic cells are embedded in an overwhelming mixture of inflammatory and immune cells. These latter contribute to tumor expansion by providing pro-survival signals and favoring immune escape. Current staging system categorizes patients in early and advanced stages reflecting tumor burden and dissemination. Overall, up to one-third of patients may recur after induction treatment and no robust biomarkers have been yet validated to identify progressors. Despite the prominence of the inflammatory immune microenvironment, the play of some key immunomodulators such as myeloid type-1 (mDC1), type-2 (mDC2) and plasmacytoid (pDC) dendritic cells (DCs) in the cellular cross-talk underlying cHL is largely unexplored.Methods: We assessed blood DCs levels in 54 newly diagnosed patients and 29 age-matched healthy controls through multi-parametric flow cytometry. The Blood Dendritic Cell Enumeration Kit from Miltenyi Biotec (Bergisch-Gladbach, Germany) was used, with 0.27 (r,0.09-0.42), 0.02 (r,0-0.04), 0.19 (r,0.09-0.37) as reference median rates for mDC1, mDC2 and pDC, respectively. Mann-Whitney, Wilcoxon sum rank, and log-rank two-sided tests were used as appropriate with p<0.05 regarded as significant.Results: The median age was 34 years (r,19-72); 23 patients (43%) had early stage [i.e. I, IIA/B, IIA extranodal (E) or bulky (X)], 31 (57%) advanced stage (i.e. IIB E or X, III and IV). B-symptoms affected 25 patients (46%) while bulky was present in 24 (44 %). Among the 23 patients with early stage, 48% had 3 or more nodal sites according to GHSG criteria while 45% of those with advanced stage had International Prognostic Score (IPS) 3 to 7. Fifty-two patients received ABVD regimen; Overall, 49 achieved a negative fluorodeoxyglucose positron emission tomography scan after the first two cycles (PET2). At a median f.u. of 33.5 mo.s, one primary progression and three relapses (<12 months: N=1; >12 months: N=2) occurred. All DCs subsets had lower frequencies in cHL patients than in healthy controls (p<0.001) (Figure 1; upper panel). In detail, in the control group, the relative median counts (25th; 75th) were 0.160 (0.06;0.3) for mDC1, 0.020 (0.01;0.02) for mDC2, 0.230 (0.16;0.32) for pDC. In the 54 cHL patients, the relative median counts (25th; 75th) were 0.050 (0.02;0.09) for mDC1, 0.006 (0.003; 0.009) for mDC2, 0.056 (0.028; 0.092) for pDC. The median rates were significantly lower for the advanced vs early stage, for both mDC1 (0.032 vs 0.070; p=0.008) and mDC2 (0.005 vs 0.009; p=0.001) subsets. Also, the median mDC2 counts were reduced in the case of bulky (0.004 vs 0.008; p=0.001) and extranodal (0.005 vs 0.006; p=0.019) disease. Patients with B symptoms had lower levels for mDC1s (p=0.029), mDC2s (p=0.005) and pDCs (p=0.020). At the end of treatment (EOT) 27 patients were reassessed: median (25th;75th) fractions of mDC1, mDC2 and pDC subsets raised from 0.036 to 0.167 (0.086; 0.250)(p< 0.001), from 0.005 to 0.012 (0.007; 0.020)(p< 0.001), from 0.042 to 0.190 (0.110; 0.300)(p< 0.001), respectively (Figure 1, lower panel). Such increases (4.6 fold for mDC1, 2.4 for mDC2, 4.5 for pDC) fully aligned circulating DCs subsets levels with those of interquartile ranges of healthy controls. EOT recovery of DCs was independent from any of the usual negative prognosticators/predictors, including IPS 3-7 and positive PET2. At a median f.u. of 35 months, PFS for the 31 patients with advanced stage showed a trend in favor of those with mDC2 levels above the median (100 vs 73%; p=0.06).Conclusions: Patients with cHL display a constitutive abatement of circulating DCs that correlated with tumor burden and dissemination (mDC1 and mDC2 subsets) and/or disease activity (pDC subset). Notably, treatment completion and response achievement were associated with a statistically significant reconstitution of circulating DCs pool into line with interquartile ranges of healthy controls. Recovery was unaffected by the presence of negative prognosticators. While patients with more compromised mDC2 levels showed a wider anatomical extent of disease and a trend towards a worse survival, analysis of larger cohorts is warranted to ascertain the prognostic impact of this finding conclusively. Results suggest that DCs may contribute to the disturbed immunological interplay cells typical of cHL and prompt a further evaluation of their value as a potential new biomarker. [Display omitted] DisclosuresPinto:Roche: Honoraria; Merck Sharp Dome: Honoraria; Celgene: Honoraria; Bristol Myers Squibb: Honoraria; Gilead: Honoraria; Millenium Takeda: Research Funding; Helssin: Honoraria; Mundipharma EDO: Speakers Bureau.

Comprehensive Analysis of the Immune Infiltrates and Aberrant Pathways Activation in Atherosclerotic Plaque

Atherosclerosis is the pathological basis of many cardiovascular and cerebrovascular diseases. The development of gene chip and high-throughput sequencing technologies revealed that the immune microenvironment of coronary artery disease (CAD) in high-risk populations played an important role in the formation and development of atherosclerotic plaques. Three gene expression datasets related to CAD were assessed using high-throughput profiling. CIBERSORT analysis revealed significant differences in five types of immune cells: activated dendritic cells (DCs), T follicular helper cells (Tfhs), resting CD4+ T cells, regulatory T cells (Tregs), and γδ T cells. Immune transcriptome analysis indicated higher levels of inflammatory markers (cytolytic activity, antigen presentation, chemokines, and cytokines) in the cases than in the controls. The level of activated DCs and the lipid clearance signaling score were negatively correlated. We observed a positive correlation between the fraction of Tfhs and lipid biosynthesis. Resting CD4+ T cells and the activity of pathways related to ossification in bone remodeling and glutathione synthesis showed a negative correlation. Gamma delta T cells negatively correlated with IL-23 signaling activity. GSEA revealed a close association with the inflammatory immune microenvironment. The present study revealed that CAD patients may have an inflammatory immune microenvironment and provides a timely update on anti-inflammatory therapies under current investigation.