Immunopharmacology and Immunotoxicology最新文献

Background: Autoimmune hepatitis (AIH) is a chronic autoimmune liver disease whose pathogenesis is closely related to the imbalance between regulatory T (Treg) and T helper 17 (Th17) cells. Rebuilding the Treg/Th17 balance provides a potential therapeutic approach for AIH patients. All-trans retinoic acid (atRA) sustains Treg cell function while inhibiting pathogenic Th17 cell differentiation. This study explored the potential of atRA for treating experimental AIH (EAH).

Methods: S100-induced EAH was established in mice, which were intraperitoneally injected with 25 mg/kg atRA every other day. Biochemical and histomorphological parameters were measured and liver histopathological changes were assessed. Hepatic CD4⁺ T cells were detected using immunofluorescence staining, and the ratios of splenic Tregs and Th17 cells were evaluated using flow cytometry. The expression levels of Rorγt and Foxp3 in the liver were assessed using real-time quantitative polymerase chain reaction (RT-qPCR) and immunoblotting. Changes in IL-6/STAT3 signaling were detected via enzyme-linked immunosorbent assay (ELISA), RT-qPCR, and immunoblotting.

Results: atRA attenuated liver inflammation in S100-induced EAH mice. Additionally, atRA decreased the infiltration of CD4⁺ T cells in the liver, increased the proportion of splenic Tregs, decreased the proportion of splenic Th17 cells, and restored the Treg/Th17 ratio. atRA also significantly reduced serum IL-6 levels and inhibited the activation of STAT3.

Conclusions: Our findings suggest that atRA ameliorated S100-induced EAH likely by suppressing the IL-6/STAT3 signaling pathway to restore the Treg/Th17 balance. Therefore, atRA may be a promising therapeutic drug for treating AIH.

Background: Microglia are brain resident cells that control neural network maintenance, damage healing, and brain development. Microglia undergo apoptosis, cytokine production, and reactive free radicals of oxygen (ROS) in response to lipopolysaccharide (LPS) stimulation. TRPM2 is activated by LPS-induced oxidative stress, but it is inhibited by carvacrol (CARV) and N-(p-amylcinnamoyl)anthranilic acid (ACA). Morphine (MRP), an opioid ligand, has the potential to be both an anesthetic and an antioxidant.

Objective: We investigated how MRP changed the TRPM2 signaling pathways to protect murine BV-2 microglia cells from LPS-induced ROS, cytokine production, and death.

Materials and methods: We generated five primary groups in the cultured BV-2 cells: Control, MRP (50 μM for 24h), LPS (1 μg/ml for 24h), LPS + MRP, and LPS + TRPM2 blockers (ACA or CARV).

Results: The incubation of LPS increased the amounts of apoptosis, cell death (propidium iodide positive cell number), oxidants (ROS and lipid peroxidation), mitochondrial dysfunction, apoptotic markers (caspase -3, -8, and -9), cytokines (TNF-α, IL-1β, and IL-6), death cell waste (debris), cytosolic free Ca²⁺, Zn²⁺, and ADP-ribose-induced TRPM2 current densities, while the treatments of MRP and TRPM2 blockers reduced their amounts. The LPS-induced reductions in BV-2 viability percentage, BV-2 number, glutathione peroxidase activity, and glutathione levels were increased by the treatments.

Conclusions: MRP reduced the levels of LPS-induced oxidative stress, inflammatory cytokines, and apoptosis via inhibiting TRPM2 in the BV-2 cells. One possible treatment option for oxidative microglia damage and neurological disorders induced by LPS could be the MRP.

Background: Combination therapy for cancer using oncolytic viruses and anticancer drugs/agents has better therapeutic effects through direct destructive effects on cancer defence. Direct destructive effects of both factors and triggering an enhanced immune response can augment the anticancer effect in a synergistic manner. e. This study aimed to evaluate the efficacy of ammonium metavanadate (NH4VO3) as an anticancer agent combined with oncolytic reovirus serotype 3, Dearing strain (ReoT3D), in the induction of cytotoxic effect in a murine colorectal cancer cell line (CT26 cells).

Methods: The impact of NH4VO3, ReoT3D, and their synergistic effect on the viability of CT26 cells was assessed using the MTT assay. The rate of apoptosis induction and cell cycle arrest by NH4VO3 and ReoT3D was evaluated by flow cytometry and real-time PCR.

Results: The results showed that cell viability decreased with increasing NH4VO3 dosage, viral titer, and treatment time. Regarding the induction of apoptosis by oncolytic reovirus and NH4VO3, apoptosis was increased because of the synergism of NH4VO3 and ReoT3D, and the cell cycle was arrested with the combined treatment. Caspase 3, 8, and p53 gene expression increased and bcl-2 gene expression decreased.

Conclusion: Combination therapy using oncolytic ReoT3D and NH4VO3 increases apoptosis in cancer cells and can be used as a promising platform for scientific studies and research in cancer treatment.

Objective: Immune checkpoint inhibitors (ICIs) made a big change in the treatment of hepatocellular carcinoma (HCC), thereby bringing fresh hope in terms of treatment to patients with few options until that time.

Methods: However, ICIs still encounter resistance mechanisms in a substantial number of patients, either in primary or secondary forms. This phenomenon of resistance occurs due to various reasons that comprise but are not restricted to epigenetic alterations, immunosuppressive tumor microenvironments, and activation of TGF-β and VEGF signaling pathways.

Results: In this study, we will discuss the mechanisms of ICI resistance in HCC and these emerging avenues of therapy as an approach to circumvent the resistance. The rationale and current status of ongoing trials to combine ICIs with anti-angiogenic agents, epigenetic modulating agents, and local therapies will be discussed.

Discussion: In a nutshell, we indicate an immediate need for reliable predictive biomarkers and personalized treatment approaches to improve clinical outcomes. Therefore, by managing challenges and knowledge gaps, this review presents a futurist outlook while charting a course for subsequent clinical trials designed to optimize immunotherapeutic results in HCC.

Objective: Atopic dermatitis (AD) is a chronic skin disease marked by immune dysregulation such as upregulated T helper (Th) 2 responses. While Th2-targeted therapies for AD are under development, their application is limited by side effects such as hypereosinophilia and arthritis. Amygdalin is a glucoside known for its anti-inflammatory and antioxidant effects. It is an essential component of bitter apricot kernel, traditionally utilized to alleviate inflammatory skin diseases such as boils and acne. This study focused on investigating the therapeutic effects of amygdalin on AD.

Materials and methods: Its effectiveness was evaluated both in vivo, using the AD mouse model induced by 2,4-dinitrochlorobenzene (DNCB) and Dermatophagoides farinae extract (DFE), and in vitro, using activated leukemia T lymphoblasts and keratinocytes.

Results: Amygdalin was shown to reduce the infiltration of immune cells in lesions and both total and DFE-specific immunoglobulin E (IgE) levels in mouse serum. Of note, it explicitly suppressed the expression of Th2 cytokines including interleukin (IL)-4, IL-5, and IL-13, as well as tumor necrosis factor (TNF)-α in ear tissues with AD induced by DNCB/DFE. These phenomena were corroborated by observations in CCRF-CEM cells, where amygdalin notably reduced the levels of IL-4 and TNF-α by inhibiting nuclear translocation of nuclear factor of activated T cells 1 and nuclear factor-κB.

Conclusion: These findings suggest that amygdalin effectively alleviates allergic skin inflammation by suppressing the Th2 and inflammatory responses, making it a promising candidate for AD treatment.

Objective: Glucocorticoids (GC) play a critical role in managing inflammatory conditions and have gained attention in cancer immunotherapy due to their immunosuppressive properties. This review explores the relationship between GC and immune checkpoint inhibitors (ICI) in cancer progression and therapy, and most importantly, synthesizes updated evidence linking GC-induced upregulation of inhibitory checkpoint molecules leading to ICI therapy failure in some cases.

Methods: This review examines the role of co-inhibitory molecules (CIMs) like programmed cell death protein-1 (PD-1), cytotoxic T-lymphocyte antigen 4 (CTLA-4), and lymphocyte activation gene-3 (LAG-3) in modulating immune responses and enabling tumor evasion. It also considers immune-related adverse events (irAEs) associated with ICI therapy, which are often mitigated using GCs. While GCs manage irAEs effectively, their influence on therapeutic outcomes remains controversial. Preclinical and clinical evidence shows that GCs may activate CIMs, potentially undermining the efficacy of immunotherapy.

Results: Preclinical studies indicate that both synthetic and endogenous GC upregulate CIMs like PD-1 and LAG-3 on immune cells, impairing immune activation and anti-tumor responses. Pharmacologic inhibition of GCs signaling, such as 11β-HSD1 inhibitors, has shown promise in enhancing ICI efficacy. GCs timing and dosage are critical; early GC use often correlates with poorer treatment responses, while later use may improve clinical outcomes.

Conclusions: This review highlights the dual role of GCs as potential immunomodulators of immune responses in cancer immunotherapy. A deeper understanding of GC-ICI interactions is vital to optimize treatment strategies. Future studies are needed to refine therapeutic approaches and individualized patient outcomes.

Objective: The study aims to develop a novel recombinant anti-LGR5 immunotoxin candidate based on a truncated form of Pseudomonas exotoxin A (ETA).

Methods: To develop this LGR5-specific recombinant immunotoxin, a corresponding single chain antibody fragment (αLGR5(scFv)) fused to ETA, was expressed under osmotic stress in the presence of compatible solutes in Escherichia coli BL21 DE3 cells. Expression was monitored by Western blot analysis facilitated by an N-terminal 10x-His tag. Purification was done using immobilized metal affinity chromatography (IMAC) and size exclusion chromatography (SEC). The recombinant immunotoxin (rIT) was assessed for cell surface binding on cervical cancer cell lines using confocal microscopy and flow cytometry. The rIT was then used in an XTT cell viability assay to assess targeted cell killing.

Results and discussion: Upon confirmation of full-length protein by Western blot, purified protein was used to confirm binding on LGR5-positive cervical cancer cell lines via confocal microscopy and flow cytometry using anti-His PE antibody as a secondary antibody. Selective cell-killing of this novel recombinant immunotoxin was illustrated by the dose-dependent reduction in cell viability at IC50 values in nanomolar concentrations on antigen-positive but not antigen-negative cell lines.

Conclusions: In conclusion, the rIT described is a promising candidate to treat cervical cancer, which however, would finally need to be confirmed by preclinical in vivo studies.

Background: Dichapetalin-type triterpenoids (DTs) derived from Dichapetalum longipetalum (Turcz.) Engl. have attracted extensive attention due to their novel structure, as well as potent anti-tumor and anti-inflammatory activities. In this study, the immunosuppressive effect of Dichapetalin-type triterpenoids on mouse peritoneal macrophages (MPMs) was studied.

Methods: MPMs were stimulated with HSV-1 or LPS for the inflammation model. The cytokines and inflammatory mediators were detected by RT-PCR. Western blotting was carried out to determine the phosphorylation of TBK1 and IRF3.

Results: Our results showed that DTs inhibited the expression of IFN-β in MPMs infected with HSV-1, and also inhibited the expression of Il-1β and Il-6 in LPS-stimulated MPMs. In addition, compound 1 (dichapetalin A) down regulated the phosphorylation of Tbk1 and Irf3 in HSV-1-infected MPMs.

Conclusion: Taken together, this study suggests that DTs isolated from the Dichapetalum longipetalum (Turcz.) Engl. inhibits macrophage activation through the cGas-STING pathway in MPMs, which would be potential for the treatment of autoimmune diseases.

Objectives: Immune checkpoint inhibitors (ICIs) are shown to improve cancer treatment effectiveness by boosting the immune system of the patient. Nevertheless, the unique and highly suppressive TME poses a significant challenge, causing heterogeneity of response or resistance in a considerable number of patients. This review aims to explore the challenges posed by the immunosuppressive tumor microenvironment (TME) in response to immune checkpoint inhibitors (ICIs) and discusses potential strategies to overcome resistance.

Material & methods: A comprehensive review of existing literature was conducted to analyze the immunosuppressive features of the TME, including the role of immunosuppressive cells, cytokine and chemokine signaling, metabolic alterations, and overexpression of immune checkpoint molecules (PD-1, CTLA-4, LAG-3, TIM-3, TIGIT, BTLA). Additionally, strategies to overcome resistance-such as targeting immunosuppressive cells, normalizing tumor vasculature, dual or triple checkpoint blockade, and combining ICIs with vaccines, oncolytic viruses, and metabolic inhibitors-are elaborated. The need for predictive biomarkers to stratify patients and assess treatment response was also discussed.

Results: The review highlights that the immunosuppressive TME contributes significantly to resistance against ICIs, mediated through various mechanisms. Potential strategies to overcome resistance include modulating the TME by targeting immunosuppressive components, combination therapies, and the identification of predictive biomarkers. Further research and innovative approaches are required to fully understand TME-ICI interactions and change the face of cancer treatment.