1.High mobility group protein B1(HMGB1) promotes myeloid dendritic cell maturation and increases Th17 cell/Treg cell ratio in patients with immune primary thrombocytopenia.
Qinzhi LI ; Dongsheng DUAN ; Xiujuan WANG ; Mingling SUN ; Ying LIU ; Xinyou WANG ; Lei WANG ; Wenxia FAN ; Mengting SONG ; Xinhong GUO
Chinese Journal of Cellular and Molecular Immunology 2025;41(1):45-50
Objective This study investigated the regulatory effect of high mobility group protein B1 (HMGB1) in the peripheral blood of patients with primary immune thrombocytopenia (ITP) on myeloid dendritic cells (mDC) and Th17/regulatory T cells (Treg) balance. Methods The study enrolled 30 newly diagnosed ITP patients and 30 healthy controls.Flow cytometry was used to measure the proportion of mDC, Th17, and Treg cells in the peripheral blood of ITP patients and healthy controls. ELISA was conducted to quantify the serum levels of HMGB1, interleukin 6 (IL-6), IL-23, IL-17, and transforming growth factor β(TGF-β). The mRNA levels of retinoic acid-related orphan receptor γt(RORγt) and forehead box P3(FOXP3) were detected by real-time PCR. The correlation between the abovementioned cells, cytokines, and platelet count was assessed using Pearson linear correlation analysis. Results The proportion of Th17 cells and the expression levels of HMGB1, IL-6, IL-23, IL-17 and the level of RORγt mRNA in the peripheral blood of ITP patients were higher than those in healthy controls. However, the Treg cell proportion and TGF-β level were lower in ITP patients than those in healthy controls. In patients with ITP, the proportion of mDC and the level of FOXP3 mRNA did not show significant changes. The proportion of mDC cells was significantly correlated with the expression of IL-6 and IL-23. Moreover, the expression of HMGB1 showed a significant correlation with the expression of mDC, IL-6, IL-23, RORγt mRNA, and IL-17. Notably, both the proportion of mDC cells and the expression of HMGB1 were negatively correlated with platelet count. Conclusion The high expression of HMGB1 in peripheral blood of ITP patients may induce Th17/Treg imbalance by promoting the maturation of mDC and affecting the secretion of cytokines, thereby potentially playing a role in the immunological mechanism of ITP.
Humans
;
Th17 Cells/cytology*
;
HMGB1 Protein/genetics*
;
T-Lymphocytes, Regulatory/cytology*
;
Female
;
Male
;
Dendritic Cells/metabolism*
;
Adult
;
Middle Aged
;
Purpura, Thrombocytopenic, Idiopathic/genetics*
;
Nuclear Receptor Subfamily 1, Group F, Member 3/genetics*
;
Young Adult
;
Interleukin-23/blood*
;
Interleukin-17/blood*
;
Interleukin-6/blood*
;
Forkhead Transcription Factors/genetics*
;
Myeloid Cells/cytology*
;
Aged
2.Zfp335 regulates the proportion of effector Treg and tumor immunity.
Xiaonan SHEN ; Wenhua LI ; Xiaoxuan JIA ; Biao YANG ; Xin WANG ; Haiyan LIU ; Anjun JIAO ; Lei LEI ; Xiaofeng YANG ; Baojun ZHANG
Chinese Journal of Cellular and Molecular Immunology 2025;41(5):385-390
Objective Zinc finger protein 335 (Zfp335) plays a crucial role in the early development of thymic T cells and the differentiation of peripheral T cell subpopulations. The objective of this study is to investigate the role and underlying mechanisms of Zfp335 in the regulation of regulatory T cell (Treg) within tumor immunity. Methods The Zfp335 gene was specifically knocked out in Treg using tamoxifen (Zfp335fl/fl FOXP3creERT2), and the MC38 tumor model was established. On the 7th day after tumor inoculation, tumor size was observed and measured. Tumor size was monitored and recorded daily starting from day 7 post-inoculation. On day 12, tumors were harvested, and the proportions of CD4+ T cells, CD8+ T cells, and Treg were analyzed by flow cytometry. Additionally, the mitochondrial function of effector regulatory T cell (eTreg) was assessed. Results From day 10 post-tumor inoculation, tumor volume in the Zfp335CKO group was significantly reduced compared to that of the wild-type (WT) group. Furthermore, the infiltration of CD4+ and CD8+ T cells, along with their respective effector cells, was significantly higher in the Zfp335CKO group than in the WT group. The proportions of CD4+ and CD8+ T cells producing interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α) were also significantly increased in the Zfp335CKO group compared to that of the WT group. In addition, the percentage of CD8+ T cells secreting granzyme B (GzmB) was significantly higher in the Zfp335CKO group than that in the WT group. In contrast, the proportion of Treg and inducible T cell co-stimulator (ICOS)+ Treg in the Zfp335CKO group was significantly lower than that in the WT group. Finally, the expression level of Mitotracker Deep Red in eTreg from the Zfp335CKO group was significantly reduced compared to that in the WT group. Conclusion During tumorigenesis, the specific deletion of Zfp335 impairs Treg activation, which is related to decreased mitochondrial function in eTreg. In Zfp335CKO mice. Tumors exhibit increased infiltration of effector T cells, accompanied by elevated levels of cytotoxic cytokines, ultimately enhancing resistance to tumor progression.
Animals
;
T-Lymphocytes, Regulatory/metabolism*
;
Mice
;
CD8-Positive T-Lymphocytes/immunology*
;
Neoplasms/genetics*
;
Cell Line, Tumor
;
Mice, Inbred C57BL
;
Mice, Knockout
;
DNA-Binding Proteins/genetics*
;
Female
3.The effects of resveratrol on osteosarcoma cells: Regulation of the interaction between JAK2/STAT3 signaling pathway and tumor immune microenvironment.
Xiaoli WANG ; Guoliang MA ; Ruidong LIU ; Ruixia QI ; Jiudei QI ; Yuguo REN
Chinese Journal of Cellular and Molecular Immunology 2025;41(5):420-427
Objective To investigate the effect of resveratrol on the tumor microenvironment in osteosarcoma. Methods A C57BL/6 xenograft mouse model was established and treated with resveratrol. Single-cell sequencing was performed to analyze changes in the tumor microenvironment. Immunohistochemistry was used to assess immune cell infiltration, while Western blotting was conducted to examine alterations in cellular signaling pathways. Results Resveratrol significantly inhibited the proliferation of LM8 osteosarcoma cells in C57BL/6 mice compared to the control group. Additionally, CD8+ T cell recruitment was enhanced. The Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) signaling pathway was notably downregulated in LM8 osteosarcoma cells following resveratrol treatment. Conclusion Resveratrol promotes CD8+ T cell infiltration by inhibiting the JAK2/STAT3 signaling pathway, suggesting its potential as a therapeutic agent in osteosarcoma treatment.
Osteosarcoma/genetics*
;
STAT3 Transcription Factor/genetics*
;
Resveratrol/pharmacology*
;
Animals
;
Janus Kinase 2/genetics*
;
Signal Transduction/drug effects*
;
Tumor Microenvironment/immunology*
;
Cell Line, Tumor
;
Mice, Inbred C57BL
;
Mice
;
Humans
;
Cell Proliferation/drug effects*
;
Bone Neoplasms/metabolism*
;
CD8-Positive T-Lymphocytes/drug effects*
;
Xenograft Model Antitumor Assays
4.Phospholipase Cβ1 (PLCB1) promotes gastric adenocarcinoma metastasis by inducing epithelial mesenchymal transition and inhibiting tumour immune infiltration and is associated with poor patient prognosis.
Lingping YUE ; Junfeng CHEN ; Qianqian GAO
Chinese Journal of Cellular and Molecular Immunology 2025;41(5):444-449
Objective To investigate whether PLCB1 expression leads to gastric adenocarcinoma metastasis and poor prognosis, and to preliminarily analyze its mechanism. Methods 122 gastric adenocarcinoma patients and their adjacent non-cancerous tissues were selected, and tissue microarray technology was used to detect the expression levels of PLCB1, epithelial cadherin(E-cadherin), vimentin and CD8+ T cells by immunohistochemistry, and scored by two pathologists. According to the immunohistochemical score of PLCB1, the patients were divided into PLCB1 high expression group (IHC>90) and PLCB1 low expression group (IHC≤90). The clinical pathological characteristics, epithelial mesenchymal transition(EMT)-related proteins and CD8+ T cells expression differences between the two groups were compared. The overall survival of the patients was collected, and COX regression analysis and Kaplan-Meier curve were used to evaluate the relationship between PLCB1 expression level and prognosis. Results PLCB1 was highly expressed in 55 cases of gastric adenocarcinoma tissues, while only 12 cases in adjacent non-cancerous tissues. The tumor invasion depth, lymph node metastasis degree and TNM stage of the PLCB1 high expression group were higher than those of the PLCB1 low expression group. Chi-square test showed that PLCB1 expression level was negatively correlated with E-cadherin (r=-0.339), positively correlated with vimentin (r=0.211), and negatively correlated with CD8+ T cells (r=-0.343). Kaplan-Meier curve analysis showed that the overall survival and disease-free survival of gastric adenocarcinoma patients with high PLCB1 expression were significantly reduced. Multivariate COX regression analysis showed that except for lymph node metastasis, tumor invasion depth, TNM stage, E-cadherin and vimentin were also independent prognostic factors for gastric adenocarcinoma patients. Conclusion PLCB1 is highly expressed in gastric adenocarcinoma, and is closely related to tumor aggressiveness and prognosis. PLCB1 may induce EMT and inhibit CD8+ T cell infiltration to affect gastric adenocarcinoma metastasis and immune response.
Humans
;
Stomach Neoplasms/genetics*
;
Epithelial-Mesenchymal Transition
;
Male
;
Female
;
Middle Aged
;
Prognosis
;
Adenocarcinoma/genetics*
;
Cadherins/metabolism*
;
Aged
;
Adult
;
CD8-Positive T-Lymphocytes/immunology*
;
Vimentin/metabolism*
;
Lymphatic Metastasis
;
Neoplasm Metastasis
5.Research on the inhibitory effects of evodiamine on activated T cell proliferation.
Jianan TANG ; Xingyan LUO ; Jingjing HE ; Xiaoxin ZENG ; Yang LIU ; Yi LAI
Chinese Journal of Cellular and Molecular Immunology 2025;41(6):524-530
Objective To explore the characteristics of the inhibitory effect of Evodiamine on the proliferation of activated T cells. Methods Mononuclear cells from peripheral blood (PBMCs) were obtained from healthy donors through density gradient centrifugation, and T cells were subsequently purified by using immunomagnetic bead separation. T cell activation was induced by employing anti-human CD3 and anti-human CD28 antibodies. T cells were treated with different concentrations of EVO (0.37, 1.11, 3.33, and 10)μmol/L. Flow cytometry was applied to evaluate the proliferation index, apoptosis rate, viability, CD25 expression levels, and cell cycle distribution of T cells. The expression levels of cytokines IL-2, IL-17A, IL-4, and IL-10 were quantified by using ELISA. Results 1.11, 3.33 and 10 μmol/L EVO effectively inhibited the proliferation of activated T cells, with an IC50 of (1.5±0.3)μmol/L. EVO did not induce apoptosis in activated T cells and affect the survival rate of resting T cells. EVO did not affect the expression of CD25 and the secretion of IL-2 in activated T cells. EVO arrested the T cell cycle at the G2/M phase, resulting in an increase in G2/M phase cells, and exhibited a concentration-dependent effect. EVO did not affect the secretion of IL-4, IL-10 by activated T cells, but significantly inhibited the secretion of IL-17A. Conclusion EVO did not significantly affect the activation process of T cells but inhibited T cell proliferation by arresting the cell cycle at the G2/M phase and significantly suppressed the secretion of the pro-inflammatory cytokine IL-17A, which suggests that EVO has the potential to serve as a lead compound for the development of low-toxicity and high-efficiency immunosuppressants and elucidates the mechanisms underlying the anti-inflammatory and immunomodulatory effects of the traditional Chinese medicine Evodia rutaecarpa.
Humans
;
Cell Proliferation/drug effects*
;
Quinazolines/pharmacology*
;
T-Lymphocytes/metabolism*
;
Lymphocyte Activation/drug effects*
;
Apoptosis/drug effects*
;
Interleukin-4/metabolism*
;
Interleukin-10/metabolism*
;
Interleukin-2 Receptor alpha Subunit/metabolism*
;
Interleukin-17/metabolism*
;
Interleukin-2/metabolism*
;
Cell Cycle/drug effects*
;
Cells, Cultured
6.The regulatory function of elevated interleukin 36γ to CD8+ T cell function in secondary fungal pneumonia patients with chronic obstructive pulmonary diseases.
Xiaoshan CUI ; Yinglan LI ; Tongxiu ZHAO
Chinese Journal of Cellular and Molecular Immunology 2025;41(7):637-643
Objectives To investigate interleukin 36γ (IL-36γ) expression, and analyze the influence of IL-36γ to CD8+ T cell activity in chronic obstructive pulmonary diseases (COPD) patients with secondary fungal pneumonia. Methods Peripheral blood was collected from 47 COPD patients, 39 COPD patients with secondary fungal pneumonia, and 20 controls. Bronchial alveolar lavage fluid (BALF) was isolated from 27 COPD patients with secondary fungal pneumonia. CD8+ T cells were purified. The levels of four IL-36 isoforms in plasma and BALF were measured by enzyme linked immunosorbent assay (ELISA). CD8+ T cells were stimulated with recombinant human IL-36γ. The levels of interferon γ(IFN-γ), tumor necrosis factor α(TNF-α), perforin and granzyme B in the cultured supernatants were measured by ELISA. Recombinant human IL-36γ-stimulated CD8+ T cells were co-cultured with NCI-H1882 cells in either direct cell-to-cell contact or TranswellTM manner. The levels of IFN-γ, TNF-α, and lactate dehydrogenase in the cultured supernatants were assessed. The percentage of target cell death was calculated. Results Plasma IL-36α, IL-36β, and IL-36γ levels were significantly elevated in both COPD group and COPD with secondary fungal pneumonia group compared with those in control group. However, only plasma IL-36γ level was higher in COPD with secondary fungal pneumonia group than that in COPD group [(200.11±99.95)pg/mL vs (53.03±87.18)pg/mL, P=0.023]. There was no remarkable difference in plasma IL-36 receptor antagonist level among three groups. IL-36γ level in BALF from infectious site was higher than that from non-infectious site in COPD with secondary fungal pneumonia group [(305.82±59.60)pg/mL vs (251.93±76.01)pg/mL, P=0.011]. IL-36γ stimulation enhanced IFN-γ, TNF-α, perforin and granzyme B secreted by CD8+ T cells. When IL-36γ-stimulated CD8+ T cells were directly mixed with NCI-H1882 cells for co-culture, the percentage of cell death was increased [(16.06±3.67)% vs (11.47±2.36)%, P=0.002]. When using TranswellTM plate for non-contact co-culture, IL-36γ-stimulated CD8+ T cell-mediated death of NCI-H1882 cells showed no significant difference compared to that without stimulation [(4.77±0.78)% vs (4.99±0.92)%, P=0.554]. Conclusion IL-36γ level in plasma and infectious site is elevated in COPD patients with secondary fungal pneumonia, which enhances the cytotoxicity of CD8+ T cells in peripheral blood and infectious microenviroment.
Humans
;
Pulmonary Disease, Chronic Obstructive/complications*
;
CD8-Positive T-Lymphocytes/metabolism*
;
Male
;
Female
;
Aged
;
Middle Aged
;
Interferon-gamma/metabolism*
;
Interleukin-1/metabolism*
;
Tumor Necrosis Factor-alpha/metabolism*
;
Lung Diseases, Fungal/complications*
;
Bronchoalveolar Lavage Fluid/chemistry*
;
Perforin/metabolism*
;
Pneumonia/immunology*
;
Granzymes/metabolism*
7.Effect of type 2 innate lymphocytes on Treg and CD8+ T cell function through IL-9 in chronic lymphocytic leukemia.
Ruixue YANG ; Xuejiao ZENG ; Jianhua QU
Chinese Journal of Cellular and Molecular Immunology 2025;41(8):673-679
Objective To investigate the differences of type 2 innate lymphocytes (ILC2) and interlukin 9 (IL-9) between chronic lymphocytic leukemia (CLL) patients and healthy controls, and to understand the effects of ILC2 on the function of regulatory T cells (Tregs), CD8+ T cells and CLL cells through IL-9. Methods Flow cytometry was used to detect the levels of ILC2 and Tregs in the peripheral blood of 45 newly diagnosed CLL patients and 24 healthy controls, and the expressions of granzyme B and perforin in CD8+ T cells in the peripheral blood of 28 patients and 15 healthy controls; ELISA was used to detect the level of IL-9 in the serum. ILC2 of patients and healthy controls was sorted by immunomagnetic beads and cultured separately, and the level of IL-9 in the culture supernatant was measured by ELISA. ILC2 sorted from CLL patients and healthy control-derived peripheral blood mononuclear cells(PBMCs) were co-cultured with the B cell leukemia MEC-1 cells, one group was supplemented with IL-9 antibody and the other group was not. After 72 hours of culture, the ratio of Tregs, programmed death 1 (PD-1), T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT), cytotoxic T lymphocyte antigen 4 (CTLA-4) on Tregs, granzyme B and perforin in CD8+ T cells were measured by flow cytometry, IL-9 level of the culture supernatant was measured by ELISA, the apoptosis of MEC-1 cells was measured by Annexin V-PI. Results Compared with the healthy control group, the levels of ILC2, Tregs and IL-9 in the CLL group increased significantly. The levels of granzyme B and perforin in CD8+ T cells were positively correlated in the peripheral blood of CLL patients. Compared with the healthy control group, IL-9 levels in the supernatant of sorted ILC2 from CLL patients increased. In the anti-IL9 antibody group, the level of PD-1 and TIGIT on Tregs decreased, and the level of granzyme B in CD8+ T cells increased significantly. The level of IL-9 in the anti-IL9 antibody group decreased statistically. And MEC-1 cells showed increased early apoptotic rate in the anti-IL9 antibody group statistically. Conclusion In CLL, ILC2 affects CD8+ T cells and Tregs through IL-9, which weakens the anti-tumor effect of CD8+ T cells, enhances the immunosuppressive effect of Tregs, and plays a role in the occurrence and development of CLL disease.
Humans
;
Leukemia, Lymphocytic, Chronic, B-Cell/immunology*
;
CD8-Positive T-Lymphocytes/immunology*
;
T-Lymphocytes, Regulatory/immunology*
;
Middle Aged
;
Male
;
Female
;
Interleukin-9/blood*
;
Aged
;
Granzymes/metabolism*
;
Perforin/metabolism*
;
Immunity, Innate
;
Adult
;
Lymphocytes/immunology*
8.Pirfenidone inhibits bladder cancer xenograft growth in mice by regulating regulatory T cells.
Hongbo ZHANG ; Mengyu YAN ; Jiandong ZHANG ; Peiwang SUN ; Rui WANG ; Yuanyuan GUO
Journal of Southern Medical University 2025;45(7):1513-1518
OBJECTIVES:
To investigate the inhibitory effect of pirfenidone (PFD) on growth of bladder cancer xenograft and its regulatory effect on Treg cells in tumor-bearing mice.
METHODS:
Thirty-two C57BL/6 mice bearing ectopic bladder tumors were randomized into control and PFD groups (n=16). In PFD group, PFD was administered orally at the daily dose of 500 mg/kg, and tumor growth and survival of the mice were monitored. After treatment for 21 days, the tumors and vital organs were harvested for analysis. Immunohistochemistry was used to assess CD3, CD4, CD8, and FOXP3 expressions in the tumors. Flow cytometry and RT-qPCR were used to analyze the percentage of CD4⁺CD25⁺FOXP3⁺ Treg cells and IL-2, IL-10, and IL-35 expressions in the tumors and spleens; organ damage of the mice was examined with HE staining.
RESULTS:
Compared with the control group, the PFD-treated mice exhibited significantly lower tumor growth rate with smaller tumor volumes at day 21, along with improved survival at day 28. Immunohistochemistry revealed no significant differences in the infiltration of CD3⁺ and CD8⁺ cells between the two groups, but the percentages of CD4⁺ and FOXP3⁺ cells were significantly lower in the tumors of PFD-treated mice. Flow cytometric analysis confirmed a decrease in CD4⁺CD25⁺FOXP3⁺ Treg cells in the tumors from PFD-treated mice, which also had reduced expression levels of IL-2, IL-10 and IL-35 mRNAs in the tumors. No significant differences were found in Treg cell populations or cytokine expressions in the spleen tissues between the two groups. HE staining showed obvious organ damage in neither of the groups.
CONCLUSIONS
PFD inhibits bladder cancer growth and enhances survival of tumor-bearing mice possibly by suppressing Treg cells in the tumor microenvironment.
Animals
;
Urinary Bladder Neoplasms/drug therapy*
;
Mice
;
T-Lymphocytes, Regulatory/metabolism*
;
Mice, Inbred C57BL
;
Interleukins/metabolism*
;
Interleukin-10/metabolism*
;
Cell Line, Tumor
;
Interleukin-2/metabolism*
;
Xenograft Model Antitumor Assays
;
Female
9.Oligodendrocyte Precursor Cell-Specific HMGB1 Knockout Reduces Immune Cell Infiltration and Demyelination in Experimental Autoimmune Encephalomyelitis Models.
Gyuree KIM ; JiHye SEO ; Bokyung KIM ; Young-Ho PARK ; Hong Jun LEE ; Fuzheng GUO ; Dong-Seok LEE
Neuroscience Bulletin 2025;41(7):1145-1160
Infiltration and activation of peripheral immune cells are critical in the progression of multiple sclerosis and its experimental animal model, experimental autoimmune encephalomyelitis (EAE). This study investigates the role of high mobility group box 1 (HMGB1) in oligodendrocyte precursor cells (OPCs) in modulating pathogenic T cells infiltrating the central nervous system through the blood-brain barrier (BBB) by using OPC-specific HMGB1 knockout (KO) mice. We found that HMGB1 released from OPCs promotes BBB disruption, subsequently allowing increased immune cell infiltration. The migration of CD4+ T cells isolated from EAE-induced mice was enhanced when co-cultured with OPCs compared to oligodendrocytes (OLs). OPC-specific HMGB1 KO mice exhibited lower BBB permeability and reduced immune cell infiltration into the CNS, leading to less damage to the myelin sheath and mitigated EAE progression. CD4+ T cell migration was also reduced when co-cultured with HMGB1 knock-out OPCs. Our findings reveal that HMGB1 secretion from OPCs is crucial for regulating immune cell infiltration and provides insights into the immunomodulatory function of OPCs in autoimmune diseases.
Animals
;
Encephalomyelitis, Autoimmune, Experimental/metabolism*
;
HMGB1 Protein/deficiency*
;
Mice, Knockout
;
Oligodendrocyte Precursor Cells/immunology*
;
Mice, Inbred C57BL
;
CD4-Positive T-Lymphocytes/immunology*
;
Cell Movement
;
Blood-Brain Barrier/immunology*
;
Mice
;
Myelin Sheath/pathology*
;
Disease Models, Animal
;
Coculture Techniques
;
Oligodendroglia/metabolism*
;
Female
;
Cells, Cultured
10.Inhibition of interferon regulatory factor 4 orchestrates T cell dysfunction, extending mouse cardiac allograft survival.
Wenjia YUAN ; Hedong ZHANG ; Longkai PENG ; Chao CHEN ; Chen FENG ; Zhouqi TANG ; Pengcheng CUI ; Yaguang LI ; Tengfang LI ; Xia QIU ; Yan CUI ; Yinqi ZENG ; Jiadi LUO ; Xubiao XIE ; Yong GUO ; Xin JIANG ; Helong DAI
Chinese Medical Journal 2025;138(10):1202-1212
BACKGROUND:
T cell dysfunction, which includes exhaustion, anergy, and senescence, is a distinct T cell differentiation state that occurs after antigen exposure. Although T cell dysfunction has been a cornerstone of cancer immunotherapy, its potential in transplant research, while not yet as extensively explored, is attracting growing interest. Interferon regulatory factor 4 (IRF4) has been shown to play a pivotal role in inducing T cell dysfunction.
METHODS:
A novel ultra-low-dose combination of Trametinib and Rapamycin, targeting IRF4 inhibition, was employed to investigate T cell proliferation, apoptosis, cytokine secretion, expression of T-cell dysfunction-associated molecules, effects of mitogen-activated protein kinase (MAPK) and mammalian target of rapamycin (mTOR) signaling pathways, and allograft survival in both in vitro and BALB/c to C57BL/6 mouse cardiac transplantation models.
RESULTS:
In vitro , blockade of IRF4 in T cells effectively inhibited T cell proliferation, increased apoptosis, and significantly upregulated the expression of programmed cell death protein 1 (PD-1), Helios, CD160, and cytotoxic T lymphocyte-associated antigen (CTLA-4), markers of T cell dysfunction. Furthermore, it suppressed the secretion of pro-inflammatory cytokines interferon (IFN)-γ and interleukin (IL)-17. Combining ultra-low-dose Trametinib (0.1 mg·kg -1 ·day -1 ) and Rapamycin (0.1 mg·kg -1 ·day -1 ) demonstrably extended graft survival, with 4 out of 5 mice exceeding 100 days post-transplantation. Moreover, analysis of grafts at day 7 confirmed sustained IFN regulatory factor 4 (IRF4) inhibition, enhanced PD-1 expression, and suppressed IFN-γ secretion, reinforcing the in vivo efficacy of this IRF4-targeting approach. The combination of Trametinib and Rapamycin synergistically inhibited the MAPK and mTOR signaling network, leading to a more pronounced suppression of IRF4 expression.
CONCLUSIONS
Targeting IRF4, a key regulator of T cell dysfunction, presents a promising avenue for inducing transplant immune tolerance. In this study, we demonstrate that a novel ultra-low-dose combination of Trametinib and Rapamycin synergistically suppresses the MAPK and mTOR signaling network, leading to profound IRF4 inhibition, promoting allograft acceptance, and offering a potential new therapeutic strategy for improved transplant outcomes. However, further research is necessary to elucidate the underlying pharmacological mechanisms and facilitate translation to clinical practice.
Animals
;
Mice
;
Mice, Inbred BALB C
;
Mice, Inbred C57BL
;
Interferon Regulatory Factors/metabolism*
;
Heart Transplantation/methods*
;
T-Lymphocytes/immunology*
;
Sirolimus/therapeutic use*
;
Pyridones/therapeutic use*
;
Graft Survival/drug effects*
;
Pyrimidinones/therapeutic use*
;
Cell Proliferation/drug effects*
;
Apoptosis/drug effects*
;
Male
;
Signal Transduction/drug effects*

Result Analysis
Print
Save
E-mail