Immunotherapy for Pulmonary Arterial Hypertension: From the Pathogenesis to Clinical Management.

Pulmonary hypertension (PH) is a progressive cardiovascular disease, which may lead to severe cardiopulmonary dysfunction. As one of the main PH disease groups, pulmonary artery hypertension (PAH) is characterized by pulmonary vascular remodeling and right ventricular dysfunction. Increased pulmonary artery resistance consequently causes right heart failure, which is the major reason for morbidity and mortality in this disease. Although various treatment strategies have been available, the poor clinical prognosis of patients with PAH reminds us that further studies of the pathological mechanism of PAH are still needed. Inflammation has been elucidated as relevant to the initiation and progression of PAH, and plays a crucial and functional role in vascular remodeling. Many immune cells and cytokines have been demonstrated to be involved in the pulmonary vascular lesions in PAH patients, with the activation of downstream signaling pathways related to inflammation. Consistently, this influence has been found to correlate with the progression and clinical outcome of PAH, indicating that immunity and inflammation may have significant potential in PAH therapy. Therefore, we reviewed the pathogenesis of inflammation and immunity in PAH development, focusing on the potential targets and clinical application of anti-inflammatory and immunosuppressive therapy.

Fine-tuning of stable organic free-radical photosensitizers for photodynamic immunotherapy.

Photodynamic immunotherapy (PDI) is an innovative approach to cancer treatment that utilizes photodynamic therapy (PDT) and photosensitizers (PSs) to induce immunogenic cell death (ICD). However, currently most commonly used PSs have restricted capabilities to generate reactive oxygen species (ROS) via a type-II mechanism under hypoxic environments, which limits their effectiveness in PDI. To overcome this, we propose a novel approach for constructing oxygen independent PSs based on stable organic free-radical molecules. By fine-tuning the characteristics of tris(2,4,6-trichlorophenyl)-methyl (TTM) radicals through the incorporation of electron-donating moieties, we successfully found that TTMIndoOMe could produce substantial amounts of ROS even in hypoxic environments. In vitro experiments showed that TTMIndoOMe could effectively produce O2˙-, kill tumor cells and trigger ICD. Moreover, in vivo experiments also demonstrated that TTMIndoOMe could further trigger anti-tumor immune response and exhibit a superior therapeutic effect compared with PDT alone. Our study offers a promising approach towards the development of next-generation PSs functioning efficiently even under hypoxic conditions and also paves the way for the creation of more effective PSs for PDI.

Unravelling Immune-Inflammatory Responses and Lysosomal Adaptation: Insights from Two-Photon Excited Delayed Fluorescence Imaging.

Two-photon excitation (TPE) microscopy with near-infrared (NIR) emission has emerged as a promising technique for deep-tissue optical imaging. Recent developments in fluorescence lifetime imaging with long-lived emission probes have further enhanced the spatial resolution and precision of fluorescence imaging, especially in complex systems with short-lived background signals. In this study, two innovative lysosome-targeting probes, Cz-NA and tCz-NA, are introduced. These probes offer a combination of advantages, including TPE (λex = 880 nm), NIR emission (λem = 650 nm), and thermally activated delayed fluorescence (TADF) with long-lived lifetimes (1.05 and 1.71 µs, respectively). These characteristics significantly improve the resolution and signal-to-noise ratio in deep-tissue imaging. By integrating an acousto-optic modulator (AOM) device with TPE microscopy, the authors successfully applied Cz-NA in two-photon excited delayed fluorescence (TPEDF) imaging to track lysosomal adaptation and immune responses to inflammation in mice. This study sheds light on the relationship between lysosome tubulation, innate immune responses, and inflammation in vivo, providing valuable insights for the development of autofluorescence-free molecular probes in the future.

JAK inhibition ameliorated experimental autoimmune encephalomyelitis by blocking GM-CSF-driven inflammatory signature of monocytes.

Monocytes are key effectors in autoimmunity-related diseases in the central nervous system (CNS) due to the critical roles of these cells in the production of proinflammatory cytokines, differentiation of T-helper (Th) cells, and antigen presentation. The JAK-STAT signaling is crucial for initiating monocytes induced immune responses by relaying cytokines signaling. However, the role of this pathway in modulating the communication between monocytes and Th cells in the pathogenesis of multiple sclerosis (MS) is unclear. Here, we show that the JAK1/2/3 and STAT1/3/5/6 subtypes involved in the demyelination mediated by the differentiation of pathological Th1 and Th17 and the CNS-infiltrating inflammatory monocytes in experimental autoimmune encephalomyelitis (EAE), a model for MS. JAK inhibition prevented the CNS-infiltrating CCR2-dependent Ly6Chi monocytes and monocyte-derived dendritic cells in EAE mice. In parallel, the proportion of GM-CSF+CD4+ T cells and GM-CSF secretion were decreased in pathological Th17 cells by JAK inhibition, which in turns converted CNS-invading monocytes into antigen-presenting cells to mediate tissue damage. Together, our data highlight the therapeutic potential of JAK inhibition in treating EAE by blocking the GM-CSF-driven inflammatory signature of monocytes.

A synthetic derivative of bioactive constituents from Isatis indigotica ameliorates hypersensitivity and arthritis by inhibiting JAK2-STAT3 pathway in mice.

The JAK-STAT pathway plays a crucial role in the signaling cascade associated with various cytokines that have been implicated in the pathogenesis of inflammatory diseases and myeloproliferative neoplasms (MPN). Among the isoforms of JAKs, the JAK2 subtype is primarily responsible for the function of hematopoietic system cells, making it a significant target in the treatment of MPN. However, the precise regulatory role of JAK2 in inflammatory diseases requires further investigation and confirmation. The current study employed a selective JAK2 inhibitor, ZT55, derived from Isatis indigotica roots, to examine its regulatory effects on inflammatory and immune responses in delayed-type hypersensitivity (DTH) and arthritis in mice. To evaluate the efficacy of ZT55 treatment, DNFB-induced DTH and collagen-induced arthritis (CIA) mouse models were utilized. T cells were cultured and subsequently analyzed for proliferation and activation using flow cytometry and EdU assay. Additionally, the maturation and function of dendritic cells were assessed through flow cytometry and ELISA. Our findings indicate that ZT55 significantly reduced DNFB-induced DTH and attenuated inflammation, cartilage degradation, and bone destruction in CIA mice. Moreover, ZT55 was found to inhibit the proliferation and activation of T cells and the maturation of dendritic cells by regulating the JAK2-STAT3 signaling pathway. These results suggest that selectively targeting the JAK2 isoform could have anti-inflammatory and immunosuppressive effects by regulating the adaptive and innate immune responses via the JAK2-STAT3 signaling pathway. Therefore, ZT55 has the potential to be a promising pharmaceutical candidate for the treatment of inflammatory and autoimmune diseases.

Bone-derived MSCs encapsulated in alginate hydrogel prevent collagen-induced arthritis in mice through the activation of adenosine A2A/2B receptors in tolerogenic dendritic cells.

Tolerogenic dendritic cells (tolDCs) facilitate the suppression of autoimmune responses by differentiating regulatory T cells (Treg). The dysfunction of immunotolerance results in the development of autoimmune diseases, such as rheumatoid arthritis (RA). As multipotent progenitor cells, mesenchymal stem cells (MSCs), can regulate dendritic cells (DCs) to restore their immunosuppressive function and prevent disease development. However, the underlying mechanisms of MSCs in regulating DCs still need to be better defined. Simultaneously, the delivery system for MSCs also influences their function. Herein, MSCs are encapsulated in alginate hydrogel to improve cell survival and retention in situ, maximizing efficacy in vivo. The three-dimensional co-culture of encapsulated MSCs with DCs demonstrates that MSCs can inhibit the maturation of DCs and the secretion of pro-inflammatory cytokines. In the collagen-induced arthritis (CIA) mice model, alginate hydrogel encapsulated MSCs induce a significantly higher expression of CD39+CD73+ on MSCs. These enzymes hydrolyze ATP to adenosine and activate A2A/2B receptors on immature DCs, further promoting the phenotypic transformation of DCs to tolDCs and regulating naïve T cells to Tregs. Therefore, encapsulated MSCs obviously alleviate the inflammatory response and prevent CIA progression. This finding clarifies the mechanism of MSCs-DCs crosstalk in eliciting the immunosuppression effect and provides insights into hydrogel-promoted stem cell therapy for autoimmune diseases.

Xueliankoufuye Suppresses Microglial Activation with Inflammatory Pain by Blocking NF-κB Signaling Pathway.

Xuelian, as a traditional Chinese ethnodrug, plays an important role in anti-inflammation, immunoregulation, promoting blood circulation, and other physiological functions. It has been prepared into different traditional Chinese medicine preparations for clinical use, with xuelian koufuye (XL) being widely used to treat rheumatoid arthritis. However, whether XL can relieve inflammatory pain and its analgesic molecular mechanism are still unknown. The present study explored the palliative effect of XL on inflammatory pain and its analgesic molecular mechanism. In complete Freund's adjuvant (CFA)-induced inflammatory joint pain, oral XL dose-dependently improved the mechanical withdrawal threshold of inflammatory pain from an average value of 17.8 g to 26.6 g (P < 0.05) and high doses of XL significantly reduced inflammation-induced ankle swelling from an average value of 3.1 cm to 2.3 cm compared to the model group (P < 0.05). In addition, in carrageenan-induced inflammatory muscle pain rat models, oral XL dose-dependently improved the mechanical withdrawal threshold of inflammatory pain from an average value of 34.3 g to 40.8 g (P < 0.05). The phosphorylated p65 was inhibited in LPS-induced BV-2 microglia and spinal cord of mice in CFA-induced inflammatory joint pain within a value of 75% (P < 0.001) and 52% reduction (P < 0.05) on average, respectively. In addition, the results showed that XL could effectively inhibit the expression and secretion of IL-6 from an average value of 2.5 ng/ml to 0.5 ng/ml (P < 0.001) and TNF-α from 3.6 mg/ml to 1.8 ng/ml with IC50 value of 20.15 µg/mL and 112 µg/mL respectively, by activating the NF-κB signaling pathway in BV-2 microglia (P < 0.001). The above-given results provide a clear understanding of the analgesic activity and mechanism of action not found in XL. Considering the significant effects of XL, it can be evaluated as a novel drug candidate for inflammatory pain, which establishes a new experimental basis for expanding the indications of XL in clinical treatment and suggests a feasible strategy to develop natural analgesic drugs.

Celastrol Targets Cullin-Associated and Neddylation-Dissociated 1 to Prevent Fibroblast-Myofibroblast Transformation against Pulmonary Fibrosis.

Celastrol (CEL), a pentacyclic triterpene compound, has been proven to have a definite antipulmonary fibrosis effect. However, its direct targets for antipulmonary fibrosis remain unknown. In this study, we designed and synthesized a series of celastrol-based probes to identify the direct targets in human pulmonary fibroblasts using an activity-based protein profiling strategy. Among many fished targets, we identified a key protein, cullin-associated and neddylation-dissociated 1 (CAND1), which was involved in fibroblast-myofibroblast transformation (FMT). More importantly, we found that the inhibitory effect of celastrol on FMT is dependent on CAND1, through improving the interactions between CAND1 and Cullin1 to promote the activity of Skp1/Cullin1/F-box ubiquitin ligases. In silico studies and cysteine mutation experiments further demonstrated that Cys264 of CAND1 is the site for conjugation of celastrol. This reveals a new mechanism of celastrol against pulmonary fibrosis and may provide a novel therapeutic option for antipulmonary fibrosis.

A highly selective JAK3 inhibitor is developed for treating rheumatoid arthritis by suppressing γc cytokine-related JAK-STAT signal.

Janus kinases (JAKs) play a critical role in immune responses by relaying signals from more than 50 cytokines, making them attractive therapeutic targets for autoimmune diseases. Although approved JAK inhibitors have demonstrated clinical efficacy, they target a broad spectrum of cytokines, which results in side effects. Therefore, next-generation inhibitors maintain efficacy, while sparing adverse events need to be developed. Among members of the JAK family, JAK3 only regulates a narrow spectrum of γc cytokines and becomes a potentially ideal target. Here, a highly JAK3-selective inhibitor Z583 is developed, which showed a potent inhibition of JAK3 with an IC50 of 0.1 nM and exhibited a 4500-fold selectivity for JAK3 than other JAK subtypes. Furthermore, Z583 completely inhibited the γc cytokine signaling and sufficiently blocked the development of inflammatory response in RA model, while sparing hematopoiesis. Collectively, the highly selective JAK3 inhibitor Z583 is a promising candidate with significant therapeutic potential for autoimmune diseases.

Quercetin Impedes Th17 Cell Differentiation to Mitigate Arthritis Involving PPARγ-Driven Transactivation of SOCS3 and Redistribution Corepressor SMRT from PPARγ to STAT3.

SCOPE: Quercetin (QU) is one of the most abundant flavonoids in plants and has attracted the attention of researchers because of its remarkable antirheumatoid arthritis (RA) effects and extremely low adverse reactions. However, the underlying mechanism needs further study. METHODS AND RESULTS: Flow cytometry, immunofluorescence, enzyme linked immunosorbent assay （ELISA）, and quantitative real-time polymerase chain reaction （qRT-PCR） reveal the obvious inhibitory effects of QU on Th17 cell differentiation in arthritic mice. More importantly, QU markedly limits the development of Th17 cell polarization, which is virtually compromised by the treatment with peroxisome proliferator activated receptor γ (PPARγ) inhibitor GW9662 and knockdown of PPARγ. Additionally, molecular dynamics simulation and immunofluorescence exhibit QU directly binds to PPARγ and increases PPARγ nuclear translocation. Besides, QU confers its moderation effect on suppressor of cytokine signaling protein (SOCS3)/signal transducer and activator of transcription 3 (STAT3) axis partially depending on PPARγ. Furthermore, coimmunoprecipitation shows QU redistributes the corepressor silencing mediator for retinoid and thyroid-hormone receptors (SMRT) from PPARγ to STAT3. Finally, the inhibition of Th17 response and the antiarthritic effect of QU are nullified by GW9662 treatment in arthritic mice. CONCLUSION: QU targets PPARγ and consequently inhibits Th17 cell differentiation by dual inhibitory activity of STAT3 to exert antiarthritic effect. The findings facilitate its development and put forth a stage for uncovering the mechanism of other naturally occurring compounds with chemical structures similar to QU.

Nintedanib exerts anti-pulmonary fibrosis activity via inhibiting TANK-binding kinase 1 (TBK1) phosphorylation.

Since triple angiokinase inhibitor could not fully explain the anti-pulmonary fibrosis activity of nintedanib (NDNB), the chemoproteomic strategy was performed to identify TANK-binding kinase 1 (TBK1) as the key target of NDNB in human pulmonary fibroblasts (HPFs). Functionally, NDNB exerts anti-fibrosis activity through impairing the p-TBK1-mediated Yes-associated protein (YAP)/transcriptional cofactor with PDZ-binding motif (TAZ) nuclear translocation.

JAK3 inhibitors for the treatment of inflammatory and autoimmune diseases: a patent review (2016-present).

INTRODUCTION: Up to now, a total of eight Janus kinase (JAK) inhibitors have been approved for the treatment of autoimmune and myeloproliferative disease. The JAK family belongs to the non-receptor tyrosine kinase family, consisting of JAK1, JAK2, JAK3, and Tyk2. Among these four subtypes, only JAK3 is mainly expressed in hematopoietic tissue cells and is exclusively associated with the cytokines shared in the common gamma-chain receptor subunit. Due to its specific tissue distribution and functional characteristics that distinguish it from the other JAKs family subtypes, JAK3 is a promising target for the treatment of autoimmune disease. AREAS COVERED: This study aimed to provide a comprehensive review of the available patent literature on JAK-family inhibitors published from 2016 to the present. In addition, an overview of the clinical activities of selective JAK3 inhibitors in recent years was provided. EXPERT OPINION: To date, no selective JAK3 inhibitors have been approved for use in clinics. Over the last 5 years, an increasing number of studies on JAK3 inhibitors, particularly ritlecitinib by Pfizer, have demonstrated their promising therapeutic potential. In this review, recent studies reported that selective JAK3 inhibitors may offer valid, interesting, and promising therapeutic potential in inflammatory and autoimmune diseases.

An efficient approach to probe the bioactive transdermal components of traditional Chinese herbal patches by UHPLC-MS: Gutong patch as a case.

BACKGROUND: Traditional Chinese herbal patches (TCHPs) characterized by good patient adherence and few side effects have been widely used in the clinic. However, their bioactive transdermal components, which are key to the quality and efficacy, have rarely been investigated. PURPOSE: Establishing an approach to probe the bioactive transdermal components of TCHPs, using Gutong patch (GTP) as a case study. STUDY DESIGN AND METHODS: GTP constituents were identified using ultrahigh-pressure liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS). The identified GTP constituents were transferred to an ultrahigh-pressure liquid chromatography coupled with triple quadrupole mass spectrometry (UHPLC-QqQ-MS/MS) method in a dynamic multiple reaction monitoring (dMRM) mode for sensitively targeted analysis of transdermal components present at low concentrations. The ex vivo transdermal components were rapidly probed using a percutaneous permeation model and the release kinetics of marker components was assessed to evaluate the release behavior of GTP. The in vivo transdermal components were then studied in a rat model of arthritis and the changes in concentration of 15 representative bioactive transdermal components with time were well revealed. RESULTS: A total of 120 phytochemical constituents have been identified in GTP extracts and 61 ex vivo transdermal components were targetedly detected. The release kinetics of GTP were evaluated by eight marker components and fitted to a zero-order kinetic model. In vivo, 62 and 40 transdermal components were observed in the skin and subcutaneous tissues of arthritic rats, respectively. The concentration-time changes of 15 representative transdermal components with documented bioactivities have been successfully exhibited after GTP administration. CONCLUSION: We established a feasible approach to probe the bioactive transdermal components of TCHPs efficiently. The integration of mass spectrometry profiling and targeted detection in dMRM mode enabled a comprehensive investigation of phytochemical constituents and their transdermal delivery, thus addressing the challenge of direct probing of diverse transdermal components present at low concentrations. This approach could be used to rapidly probe the bioactive components and understand the mechanism of TCHPs.

Denudatine-type diterpenoid alkaloids from an aqueous extract of the lateral root of Aconitum carmichaelii.

Five new denudatine-type diterpenoid alkaloids (1-5), along with the known analogue aconicarmine (6), were isolated from an aqueous decoction of the lateral roots of Aconitum carmichaelii (fu-zi). Their structures were determined by spectroscopic data analysis and electronic circular dichroism (ECD) calculations. Compound 5 is the first denudatine-type diterpenoid alcohol iminium alkaloid, which could be partially transformed into the aza acetal form in pyridine-d5. Compound 5 inhibited mice writhing in an acetic acid-induced writhing assay.

Divanillyl sulfone suppresses NLRP3 inflammasome activation via inducing mitophagy to ameliorate chronic neuropathic pain in mice.

BACKGROUND: Chronic neuropathic pain is a frequent sequel to peripheral nerve injury and maladaptive nervous system function. Divanillyl sulfone (DS), a novel structural derivative of 4,4'-dihydroxydibenzyl sulfoxide from a traditional Chinese medicine Gastrodia elata with anti-nociceptive effects, significantly alleviated neuropathic pain following intrathecal injection. Here, we aimed to investigate the underlying mechanisms of DS against neuropathic pain. METHODS: A chronic constrictive injury (CCI) mouse model of neuropathic pain induced by sciatic nerve ligation was performed to evaluate the effect of DS by measuring the limb withdrawal using Von Frey filament test. Immunofluorescence staining was used to assess the cell localizations and expressions of Iba-1, ASC, NLRP3, and ROS, the formation of autolysosome. The levels of NLRP3-related proteins (caspase-1, NLRP3, and IL-1ß), mitophagy-related proteins (LC3, Beclin-1, and p62), and apoptosis-related proteins (Bcl-XL and Bax) were detected by Western blotting. The apoptosis of BV-2 cell and caspase activity were evaluated by flow cytometry. RESULTS: DS significantly alleviated the neuropathic pain by increasing the mechanical withdrawal threshold and inhibiting the activation of NLRP3 in CCI-induced model mice. Our findings indicated that DS promoted the mitophagy by increasing the LC3II and Beclin 1 and decreasing the levels of p62 protein in BV-2 cell. This is accompanied by the inhibition of NLRP3 activation, which was shown as inhibited the expression of NLRP3 in lysates as well as the secretion of mature caspase-1 p10 and IL-1ß p17 in supernatants in cultured BV-2 microglia. In addition, DS could promote mitophagy-induced improvement of dysfunctional mitochondria by clearing intracellular ROS and restoring mitochondrial membrane potential. CONCLUSION: Together, our findings demonstrated that DS ameliorate chronic neuropathic pain in mice by suppressing NLRP3 inflammasome activation induced by mitophagy in microglia. DS may be a promising therapeutic agent for chronic neuropathic pain.

Therapeutic potential of the target on NLRP3 inflammasome in multiple sclerosis.

Inflammasomes are multi-protein macromolecular complexes that typically comprise of three units, a sensor, an adaptor and procaspase-1. The assembly of each inflammasome is dictated by a unique pattern recognition receptors (PRRs) in response to pathogen-associated molecular patterns (PAMPs) or other endogenous danger-associated molecular patterns (DAMPs) in the cytosol of the host cells, and promote the maturation and secretion of IL-1ß and IL-18 during the inflammatory process. Specific inflammasomes are involved in the host defense response against different pathogens, and the latter have evolved multiple corresponding mechanisms to inhibit inflammasome activation. The nucleotide-binding oligomerization domain leucine-rich repeat and pyrin domain-containing 3 (NLRP3) inflammasome is the best understood in terms of molecular mechanisms, and is a promising therapeutic target in immune-related disorders. Multiple sclerosis (MS) is an autoimmune disease characterized by inflammatory demyelination of white matter in the central nervous system, increased levels of IL-1ß in the cerebrospinal fluid (CSF) of relapsed patients, and deposition of caspase-1 in the spinal cord. The direct involvement of the NLRP3 inflammasome in the occurrence and development of MS was ascertained in the experimental autoimmune encephalomyelitis (EAE) animal model. In this review, we have focused on the mechanisms underlying activation of the NLRP3 inflammasome in MS or EAE, as well as inhibitors that specifically target the complex and alleviate disease progression, in order to unearth new therapeutic strategies against MS.

Emerging small-molecule inhibitors of the Bruton's tyrosine kinase (BTK): Current development.

Therapy based on Bruton's tyrosine kinase (BTK) inhibitors one of the major treatment options currently recommended for lymphoma patients. The first generation of BTK inhibitor, Ibrutinib, achieved remarkable progress in the treatment of B-cell malignancies, but still has problems with drug-resistance or off-target induced serious side effects. Therefore, numerous new BTK inhibitors were developed to address this unmet medical need. In parallel, the effect of BTK inhibitors against immune-related diseases has been evaluated in clinical trials. This review summarizes recent progress in the research and development of BTK inhibitors, with a focus on structural characteristics and structure-activity relationships. The structure-refinement process of representative pharmacophores as well as their effects on binding affinity, biological activity and pharmacokinetics profiles were analyzed. The advantages and disadvantages of reversible/irreversible BTK inhibitors and their potential implications were discussed to provide a reference for the rational design and development of novel potent BTK inhibitors.

Exploring a novel triptolide derivative possess anti-colitis effect via regulating T cell differentiation.

Inflammatory bowel disease (IBD) is generally characterized by chronic inflammatory disorders of the gastrointestinal tract that are known as ulcerative colitis (UC) or Crohn's disease (CD). Although the underlying mechanism of action of IBD is unclear and because of the lack of satisfactory treatment, increasing evidence has indicated that pro-inflammatory cytokines that activate JAK-STAT signaling pathway regulate the differentiation of naïve T cells towards T helper (Th)1 and Th17 cell subsets and contribute to the development of IBD. ZT01 is a newly obtained triptolide derivative with strong anti-inflammatory effects and low toxicity. In this study, we evaluated the effects of ZT01 on DSS-induced colitis and investigated the underlying mechanism of action involved. Mice with DSS-induced acute or chronic colitis were used to assess the efficacy of ZT01 treatment, and T cells were cultured to analyze the differentiation of Th1 and Th17 cell by flow cytometry. In addition, intestinal epithelial barrier function, macrophage polarization, activation of the JAK-STAT signaling pathway, and the expression of cytokines and transcription factors were measured to assess the possible mechanisms of ZT01. We found that ZT01 had an obviously beneficial effect on DSS-induced colitis by improving the symptoms of bloody diarrhea, weight loss, and a shortened colon, thereby preserving the epithelial barrier function in the mouse colon. Furthermore, ZT01 significantly inhibited T cell differentiation into Th1 and/or Th17 cell subsets and macrophage polarization towards into an inflammatory phenotype via regulating the JAK-STAT signaling pathway. Thus, our findings suggested that ZT01 might be a potential pharmaceutical candidate that deserves to be further investigated as a treatment for IBD patients.

Methotrexate enhances antigen presentation and maturation of tumour antigen-loaded dendritic cells through NLRP3 inflammasome activation: a strategy for dendritic cell-based cancer vaccine.

BACKGROUND: Dendritic cells (DCs) are antigen-presenting cells that play a pivotal role in adaptive cell-mediated immunity by priming and activating T cells against specific tumour and pathogenic antigens. Methotrexate (MTX), a folate derivative, functions as an immunoregulatory agent. However, the possible effect of MTX on tumour antigen-loaded DCs has not yet been investigated. METHODS: We analysed the effect of MTX on the maturation and function of DCs along with tumour cell lysates (TCLs). Using bone marrow-derived DCs, we investigated the effect of MTX combined TCL-loaded DCs on T cells priming and proliferation. We also tested the anti-tumour immune effect on DCs when treated with MTX and/or TCL in vivo. RESULTS: MTX combined with TCL not only enhanced DC maturation and stimulated cytokine release but also promoted CD8+ T cell activation and proliferation. The latter was associated with increased tumour antigen uptake and cross-presentation to T cells. Mechanistically, DC maturation and antigen presentation were partly modulated by NLRP3 inflammasome activation. Furthermore, immunisation of mice with MTX and TCL-pulsed DCs before a tumour challenge significantly delayed tumour onset and retarded its growth. This protective effect was due to priming of IFN-γ releasing CD8+ T cells and enhanced killing of tumour cells by cytotoxic T lymphocytes isolated from these immunised mice. CONCLUSION: MTX can function as a potent adjuvant in DC vaccines by increasing antigen presentation and T cell priming. Our findings provide a new strategy for the application of DC-based anti-tumour immunotherapy.