Immunopharmacology and Immunotoxicology最新文献

Objectives: Chitosan is widely used in medicine to regulate immune responses in T cells and dendritic cells. However, research on the regulation of mast cells (MCs) is scarce. Mas-related G-protein-coupled receptor X2 (MRGPRX2) is a key receptor that mediates MC activation. However, the inhibitory effects of chitosan on MRGPRX2 activation have not yet been reported. The aim of this study was to determine whether chitosan inhibits MRGPRX2-mediated MC activation and the molecular weight of chitosan with the best inhibitory effect.

Methods: Cytotoxic and activating effects of chitosan on LAD2 cells were evaluated in vitro. An in vitro MC degranulation reaction model and in vivo C48/80-induced local passive anaphylaxis mouse model were used to evaluate the inhibitory effect of chitosan on MRGPRX2 activation.

Key findings: Chitosan inhibited MC degranulation mediated by MRGPRX2 in vitro and reduced histamine, β-hexosaminidase, and cytokine release. Chitosan inhibited local pseudo-allergy and inflammatory mediator release by inhibiting MRGPRX2-mediated MC activation. Moreover, low-molecular-weight chitosan exhibited superior inhibitory activity against MRGPRX2.

Conclusions: Chitosan inhibited MRGPRX2-mediated MC degranulation in vivo and in vitro. Low molecular weight chitosan has the potential to be developed as a functional drug or food to assist in the treatment of MRGPRX2-regulated diseases.

Background: The incidence of hepatic immune-related adverse events has increased with the wide use of immune checkpoint inhibitors (ICIs), some immune-mediated hepatotoxicity (IMH) cases are severe and lack of clinical recommendations.

Objective: This study aimed to evaluate the efficacy of artificial liver support systems (ALSSs) in the treatment of IMH.

Methods: This retrospective case series included six patients with grade 4 hepatotoxicity with high bilirubin induced by ICIs treated between 1 January 2019 and 31 December 2021. All patients received ALSS treatment.

Results: After treatment and recovery, four of the six patients experienced improvement in hepatotoxicity, with total bilirubin (TBIL) levels reduced to ≤ grade 2, and two patients achieved complete recovery (TBIL grade = 0).

Conclusion: ALSS serve as a therapeutic option for severe IMH.

Objective: C-Phycocyanin (C-PC) is a photosynthetic pigment with interesting therapeutic properties. However, its effectiveness in modulating the immune system cell populations has not been elucidated. We analyzed the action of C-PC on the modulation of mice immune system.

Methods: The animals were treated subcutaneously with C-PC for 3 consecutive days. On the fourth day, the animals were euthanized and cells from different organs were analyzed by flow cytometry. Cytotoxicity was analyzed using biochemical parameters.

Results: The results showed that C-PC increased the total cellularity in percentage and absolute number in the inguinal lymph node as well as the absolute number of B cells, CD4+ and CD8+ T cells and myeloid cells. The percentage of B cells was also increased in the lymph node. In the bone marrow, there was a reduction in immature and mature B cells. In contrast, C-PC increased the percentage and absolute number of myeloid cells in the bone marrow. C-PC administration also promoted an increase of CD4+ and CD8+ T cells in the thymus, and a reduction in these populations in the spleen.

Conclusion: The data show for the first time the positive immunomodulatory role of C-PC by recruiting distinct populations of immune system cells to the treatment-draining lymphoid organ.

Objectives: Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease in children. Nonsteroidal anti-inflammatory drugs (NSAIDs) and intra-articular corticosteroid injections are first-line therapy for oligoarticular JIA. NSAIDs Adverse events (AEs) include gastrointestinal ulcers/bleeding and impaired renal function. The most prescribed NSAIDs for oligoarticular JIA are ibuprofen and naproxen. However, direct comparison between these drugs is lacking. We aimed to compare the efficacy and safety of ibuprofen versus naproxen for oligoarticular JIA.

Methods: This is a bi-national retrospective study of oligoarticular JIA patients treated with either ibuprofen or naproxen as first-line therapy. Efficacy was defined as patients that achieved complete response (no evidence for arthritis). Safety was assessed by the occurrence of adverse events during follow-up.

Results: Of 164 patients, 103 were treated in the Israeli group and 61 in the US group. The study population had a mean age of 4.49 ± 3.55 years, with F:M ratio of ∼2.5:1. No significant difference was found in drug efficacy [Complete response was observed in 15% of the ibuprofen group vs. 17.3% in naproxen group (p = 0.7)]. Treatment duration > 28 days was associated with significantly higher odds for complete response (p = 0.021). For safety, 12 AEs were associated with naproxen, whereas no AEs were associated with ibuprofen (p = 0.004). Treatment was discontinued in all AEs cases.

Conclusions: Ibuprofen and naproxen showed similar albeit low efficacy which emphasizes their role as bridging therapy until IACI is achieved. However, ibuprofen showed better safety profile naproxen and therefore should be considered as first-line therapy.

Objectives: Periodontal disease is a chronic inflammatory disease caused by periodontopathogenic bacteria, and its progression leads to periodontal tissue destruction and tooth loss. Zerumbone is a bioactive substance found in ginger (Zingiber zerumbet) and is known to have bioactive effects such as anticancer effects, but there have been no attempts to use it for periodontitis treatment. In addition, there have been no reports examining its effects on periodontal tissue component cells. In this experiment, we aimed to determine whether zerumbone affects the production of inflammatory mediators induced by tumor necrosis factor (TNF)-α in human periodontal ligament cells (HPDLCs), including its effects on signaling pathways.

Methods: HPDLCs were stimulated by TNF-α (10 ng/ml) with or without zerumbone (6.25, 12.5, or 25 µM). Cytokine production in supernatant was determined using ELISA. Activation of signal transduction pathways and intracellular protein expression were investigated using the western blot analysis.

Results: Zerumbone significantly suppressed TNF-α-induced production of CC chemokine ligand 2 (CCL2), CCL20, CXC chemokine ligand 10 (CXCL10), and interleukin-6 (IL-6) in HPDLCs. In addition, zerumbone decreased intercellular adhesion molecule-1 (ICAM-1) and cyclooxygenase-2 (COX-2) expression in TNF-α-stimulated HPDLCs. Furthermore, zerumbone suppressed activation of nuclear factor (NF)-κB and signal transducer and activator of transcription 3 (STAT3) pathways in TNF-α-treated HPDLCs. Finally, zerumbone enhanced the production of heme oxygenase-1 (HO-1), an antioxidant enzyme, in HPDLCs.

Conclusion: These results suggest that zerumbone suppressed the production of several inflammatory mediators by inhibiting the NF-κB and STAT3 pathways in HPDLCs.

Objective: Multiple sclerosis (MS) is a prevalent autoimmune disorder characterized by neuroinflammation and demyelination in the central nervous system (CNS), leading to neurological dysfunction. Despite advances in treatment, there remains an unmet need for safe and effective therapies. Crocin, a bioactive constituent of saffron, has demonstrated anti-inflammatory and immunoregulatory properties in various disease models. This study investigates the therapeutic potential of Crocin in a murine model of MS, experimental autoimmune encephalomyelitis (EAE).

Methods and results: Female C57BL/6 mice were induced with EAE and treated with different doses of Crocin. Clinical severity, CNS pathology, T cell proliferation, cytokine production, and transcription factor expression were assessed. Crocin-treated mice showed reduced clinical severity, inflammation, and demyelination in the CNS compared to controls. Moreover, Crocin attenuated T cell proliferation and modulated cytokine production, promoting an anti-inflammatory cytokine profile while suppressing pro-inflammatory cytokines. Additionally, Crocin altered the expression of transcription factors associated with T cell differentiation, favoring regulatory T cell responses.

Discussion: These findings suggest that Crocin exerts therapeutic effects in EAE by modulating neuroinflammation and immune responses. Further studies are warranted to elucidate the mechanisms underlying Crocin's immunomodulatory properties and its potential as a treatment for MS.

Background: One of the common findings in systemic sclerosis (SSc) patients has been long-term exposure to environmental toxins such as pesticides. However, the data available shows an equivocal association between pesticide exposure and autoimmunity in SSc.

Methods: We investigated the levels of organochlorine pesticides (OCPs) in blood of 20 SSc patients and 17 healthy controls, and also studied their effect in-vitro on T lymphocytes and their functional responses.

Results: We found higher levels of hexachlorocyclohexane (HCH- α-, β-, and γ) and o,p'-dichlorodiphenyltrichloroethane (DDT) metabolite (p,p΄-DDE) in blood of SSc patients. In vitro treatment of SSc patient PBMCs with either of HCH (100 mM) or DDT (50 µM) caused a significant increase merely in CD8⁺ memory (CD8⁺CD45RO⁺) T lymphocytes. We also observed reduced FoxP3 expression in CD4⁺CD25⁺ (regulatory T cells) of SSc patients. Neither HCH nor DDT exposure of SSc PBMCs altered significantly the secretion of IL-2, IL-10, or IFN-γ, but both of these pesticides elevated their IL-4 (a pro-fibrotic cytokine) secretion.

Conclusion: Taken together, our findings indicate that persistent exposure to these OCPs results in decreased lymphoproliferative activity which promotes disease activity by producing pro-fibrotic cytokine(s). Thus, SSc patients are less able to initiate or augment an immune response to foreign antigens, when there is substantial suppression of lymphocyte function, which increases their susceptibility to infection. Strategies to prevent and control pesticide exposure may play an important role in reducing the morbidity and mortality associated with this disease.

Objective: Triple-Negative Breast Cancer (TNBC), the most challenging subtype of Breast Cancer (BC), currently lacks targeted therapy, presenting a significant therapeutic gap in its management. Tumor Associated Macrophages (TAMs) play a significant role in TNBC progression and could be targeted by repolarizing them from M2 to M1 phenotype. Matairesinol (MAT), a plant lignan, has been shown to exhibit anticancer, anti-inflammatory and immunomodulatory activities. In this study, we explored how MAT-induced repolarization of THP-1-derived M2 macrophages towards the M1 phenotype, which could effectively target the TNBC cell line, MDA-MB-231.

Methods: The differential expression of genes in THP-1-derived macrophages at mRNA levels was evaluated by RNAseq assay. An inverted microscope equipped with a CMOS camera was utilized to capture the morphological variations in THP-1 cells and THP-1-derived macrophages. Relative mRNA expression of M1 and M2 specific marker genes was quantified by qRT-PCR. Cell viability and induction of apoptosis were evaluated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolylcarbocyanine iodide (JC-1 dye) assays, respectively.

Results: MAT reduced the viability of M2a and M2d macrophages and repolarized them to M1 phenotype. Conditioned medium (CM) from MAT-treated M2a and M2d macrophages significantly reduced the viability of TNBC cells by apoptosis.

Conclusion: Targeting M2 macrophages is an important strategy to regulate cancer progression. Our study provides evidence that MAT may be a promising drug candidate for developing novel anti-TNBC therapy. However, further studies are warranted to thoroughly elucidate the molecular mechanism of action of MAT and evaluate its therapeutic potential in TNBC in vitro and in vivo models.

Background: Ulcerative colitis (UC) is a frequent inflammatory bowel disease (IBD) that causes long-lasting inflammation in the innermost lining of the rectum and colon.

Objective: The aim of this study was to evaluate the therapeutic effect of Cannabis sativa (C. sativa) on the amelioration of acetic acid-induced colitis in rats.

Materials and methods: Group 1: normal control group was intrarectally administered saline solution (0.9%); group 2: acetic acid (AA) group was given AA intra-rectally (2 mL of 4% (v/v) in 0.9% NaCl) once.; group 3&4: This group represented the ulcerative colitis-induced rats that were injected with acetic acid intra-rectally, then s.c. injection with C. sativa (20 and 40 mg/kg daily for 8 days).

Results: Colonic architectural abnormality significantly improved after pretreatment with C. sativa. Additionally, it significantly reduced the MDA level and prevented the depletion of GSH content. Moreover, C. sativa administration showed suppressive activities on pro-inflammatory cytokines, including NF-κB, MAPK, ERK, PI3K, AKT, HIF-1α, and TLR4. Moreover, it significantly upregulated the level of SIRT and CB1 in the colon tissue.

Conclusion: This study provided a novel impact for CB1 receptor activation produced by C. sativa against AA-induced UC in rats through inhibiting the TLR-4 MAPK/ERK, PI3K, and NFκB signaling pathways.

Background: Rhino-Orbital-Cerebral Mucormycosis (ROCM) cases increased sharply in India during the second COVID-19 wave. Due to uncontrolled hyperglycemia, prolonged steroid use, and high ferritin levels, the immune system was dysregulated throughout this surge.

Methods: Our study examined post-COVID-19 ROCM patients' T regulatory cell (Treg), T helper 17 cell (Th17) and Myeloid derived suppressor cell (MDSC) levels before and after three months of treatment. T cell activation and MDSC profile were measured in peripheral blood from 20 post-COVID-19 mucormycosis patients and 20 age-matched controls.

Results: Compared to controls, cases had significantly greater Th17 cells (CD4⁺IL-23R⁺) before and after treatment (p < 0.05), with no significant change between pre- and post-treatment. In pretreatment cases, Treg cells (CD4⁺CD25⁺FoxP3⁺) were lower than controls, but dramatically increased (p < 0.05) following treatment. Further, these patients had significantly higher rates of monocytic (m) MDSCs (CD14⁺HLA-DR^low/-) compared to healthy persons (p < 0.05). Interestingly, after three months of treatment, mMDSC levels dropped to levels similar to healthy controls. Similarly, ROCM patients had higher levels of granulocytic (g) MDSCs (HLA-DR^low/-CD33⁺CD11b⁺CD66⁺) than healthy controls, although these levels normalized after three months. Patients had considerably greater expression levels of RORγt, TGF-β, and IL-10 mRNA before therapy compared to healthy controls. FoxP3 and Arg-1 mRNA expression was lower in pretreatment patients than in healthy people. After treatment, these individuals' IL-10, FoxP3, and Arg-1 mRNA expression increased.

Conclusion: MDSCs may play a role in mucormycosis immunological dysregulation, suggesting that restoring balance may improve patient outcomes.