Cytotoxic CD4⁺ T cells (CD4⁺ CTLs) represent a novel subset of T cells with cytotoxic effects. They recognize target cells in an antigen-specific manner, relying on class II major histocompatibility complex (MHC-II) interactions. CD4⁺ CTLs exert cytotoxic effects on target cells by secreting cytotoxic molecules such as granzymes, perforin, and granulysin. Recent studies have revealed their significant roles in various autoimmune diseases. This review focuses on the differentiation, phenotypic characteristics, and roles of CD4⁺ CTLs in different types of autoimmune disorders, aiming to provide new insights for the prevention and treatment of these diseases.
Humans ; Autoimmune Diseases/immunology* ; CD4-Positive T-Lymphocytes/immunology* ; Animals ; T-Lymphocytes, Cytotoxic/immunology* ; Perforin/immunology* ; Granzymes/immunology*

Hepatocellular carcinoma (HCC) is one of the fastest growing cancers in the world, ranking fourth among the causes of cancer-induced death in the world. At present, the field of HCC treatment is developing rapidly, and immunotherapy has been recognized as a promising treatment method, in which T cells play a key role in HCC immunotherapy. However, in the case of virus infection or in tumor microenvironment (TME), T cells will be continuously stimulated by antigens and then fall into the state of T cell exhaustion (Tex). This state will not only reduce the immunity of patients but also lead to poor efficacy of immunotherapy. Therefore, to deeply analyze the mechanism of Tex and to explore effective strategies to reverse Tex is the key point in the immunotherapy for HCC. This review aims to summarize the mechanism of Tex in HCC patients, and the current situation and shortcomings of drug research and development to reverse Tex at this stage, in order to provide theoretical basis for the optimization of immunotherapy regimen for HCC patients.
Humans ; Carcinoma, Hepatocellular/therapy* ; Liver Neoplasms/therapy* ; Immunotherapy/methods* ; T-Lymphocytes/immunology* ; Tumor Microenvironment/immunology* ; Animals ; T-Cell Exhaustion

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 (Zfp335^fl/fl FOXP3^creERT2), 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 Zfp335^CKO 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 Zfp335^CKO 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 Zfp335^CKO 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 Zfp335^CKO group than that in the WT group. In contrast, the proportion of Treg and inducible T cell co-stimulator (ICOS)⁺ Treg in the Zfp335^CKO group was significantly lower than that in the WT group. Finally, the expression level of Mitotracker Deep Red in eTreg from the Zfp335^CKO 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 Zfp335^CKO 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

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

Objective This study aimed to analyze the characteristics and clinical significance of peripheral lymphocytic subsets and cytokine levels, including interleukin 1β(IL-1β), IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12P70, IL-17A, tumor necrosis factor α(TNF-α), interferon γ(IFN-γ) and IFN-α, in patients with primary biliary cholangitis (PBC), to provide some novel insights into the pathogenesis of PBC. Methods We retrospectively collected clinical features and laboratory data from hospitalized patients who were primarily diagnosed with PBC and from healthy physical examinees at the Third People's Hospital of Changzhou between January 1, 2023, and June 30, 2024. Results A total of 152 PBC patients and 96 healthy controls who met the inclusion and exclusion criteria were enrolled. Significant differences were observed in baseline characteristics and laboratory data between the two groups. After the propensity score matching (PSM) analysis, 61 PBC patients and 61 healthy controls were successfully matched, ensuring that the general characteristics (age and gender) of the two groups were balanced and comparable. Compared to the control group, the proportion of peripheral lymphocytes was significantly higher in the PBC group (31.9% vs. 17.8%), primarily due to an increase in CD4⁺ T cells (46.77% vs. 41.19%), while CD8⁺T cells were significantly decreased (19.73% vs. 22.07%). Notably, the proportions of CD4⁺ programmed cell death 1 (PD-1)⁺ T and CD8⁺PD-1⁺ T cells were elevated, with CD8⁺PD-1⁺ T cells showing a significant positive correlation with the severity of liver inflammation (r=0.41). Furthermore, the mitochondrial mass (MM) of CD4⁺ T cells was significantly increased in PBC patients, whereas no significant changes were observed in the MM of CD8⁺ T cells or the mitochondrial membrane potential (MMP) of CD3⁺ T cells. Additionally, the plasma levels of cytokines, such as IL-4, IL-8, IL-10 and IFN-α, were abnormally elevated. The plasma levels of IL-5 and IL-1β were negatively correlated with the stage of liver fibrosis in patients with PBC (r=-0.52). Conclusion The overactivation and proliferation of CD4⁺ T cells, along with the suppression of CD8⁺ T cell function and increased PD-1 expression leads to T cell exhaustion, indicating significant immunological alterations in PBC patients. These changes are closely associated with the disease progression. Additionally, cytokines are likely involved in the immune regulation process of PBC and may influence the pathogenic mechanisms of the disease. Regular monitoring of lymphocyte subsets and cytokine levels can help assess the immune status and disease activity in patients with PBC, thereby guiding the individualized treatment strategies.
Humans ; Male ; Female ; Middle Aged ; Liver Cirrhosis, Biliary/blood* ; Retrospective Studies ; T-Lymphocyte Subsets/immunology* ; Aged ; Cytokines/blood* ; Adult ; CD8-Positive T-Lymphocytes/immunology*

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

Hepatitis B virus (HBV)-specific CD8⁺ T cells play a central role in controlling HBV infection; however, their function is impaired during chronic HBV infection, manifesting as a state of dysfunction. Recent studies have revealed that CD8⁺ T cell dysfunction in chronic HBV infection differs from the classical exhaustion observed in other viral infections or tumors. In 2024, several pivotal studies further elucidated novel mechanisms underlying CD8⁺ T cell dysfunction in chronic HBV infection and identified new therapeutic targets, including 4-1BB and transforming growth factor-beta (TGF-β). This review, while elucidating the dysfunction of CD8⁺ T cells in chronic HBV infection and its underlying mechanisms, focuses on summarizing the key findings from these latest studies and explores their translational value and clinical significance.
Humans ; Hepatitis B, Chronic/virology* ; CD8-Positive T-Lymphocytes/immunology* ; Hepatitis B virus/physiology* ; Animals ; Transforming Growth Factor beta/immunology*

Chimeric antigen receptor T (CAR-T) lymphocytes are at the forefront of adoptive immunotherapy research, and this technology has significantly advanced the prospects of tumor immunotherapy. CAR-T therapy has demonstrated remarkable efficacy in haematological tumours of lymphoid origin and provided therapeutic possibility for solid tumours. Currently, CAR-T cell preparation predominantly involves transfection of T cells with viral vectors. However, the production of viral vectors is time-consuming, expensive, and the vectors have low loading capacity, along with insertion instability. Consequently, there is a pressing need to develop more convenient and precise non-viral gene delivery methods. This paper reviews the most promising non-viral gene delivery technologies, including CRISPR/Cas9 gene editing, transposon systems such as Sleeping Beauty (SB) and PiggyBac (PB), and mRNA, and anticipates the future development of non-viral vector-based CAR-T therapies.
Humans ; Immunotherapy, Adoptive/methods* ; Receptors, Chimeric Antigen/immunology* ; Animals ; Gene Transfer Techniques ; Genetic Vectors/genetics* ; Gene Editing ; CRISPR-Cas Systems/genetics* ; DNA Transposable Elements/genetics* ; T-Lymphocytes/immunology* ; Neoplasms/immunology*

Chronic anemia patients (such as thalassemia) often rely on long-term red blood cell transfusion to sustain life. However, alloimmune reactions against blood group antigens can pose serious risks to the patients' clinical treatment and survival. The regulatory mechanisms of transfusion-related alloimmunity are not yet well understood. For example, some patients, despite long-term transfusions, do not develop alloimmune reactions, while others produce alloantibodies against multiple blood group antigens, making transfusion therapy increasingly difficult. Red blood cell blood group alloimmunity involves various immune cells, including antigen-presenting cells and different T cells. Many studies are exploring the regulatory roles and even potential interventions. This article reviews the correlation between cellular immunity and red blood cell blood group antigens in alloimmune responses, and explores the interaction between the two, as well as their impact on immune responses.
Humans ; Immunity, Cellular/immunology* ; Erythrocytes/immunology* ; Blood Group Antigens/immunology* ; Animals ; Isoantibodies/immunology* ; T-Lymphocytes/immunology*

Objective To investigate the therapeutic effects of interleukin 23p19(IL-23p19) monoclonal antibody in the MRL/lpr lupus-like mouse model. Methods A total of 36 female MRL/lpr mice aged 8 weeks were randomly divided into 6 groups: PBS group (blank control), IgG group (isotype IgG), dexamethasone (DEX) group (positive control), and three IL-23p19 monoclonal antibody treatment groups with different dose gradients: low dose (LD, 1 mg/kg), medium dose (MD, 3 mg/kg), and high dose (HD, 10 mg/kg). Drug intervention began at 12 weeks of age via tail vein injection. Urine protein levels were measured using urine protein test strips; serum anti-dsDNA antibody levels were detected by ELISA; serum creatinine and blood urea nitrogen levels were measured using an automatic biochemical analyzer; renal histopathological changes were analyzed by H&E and PAS staining; immunofluorescence was used to assess IgG and C3 immune complex deposition in kidney tissues; flow cytometry was employed to examine the expression of T helper 1(Th1), Th2, Th17, T follicular helper (Tfh), and regulatory T cells(Treg) cell subsets in the spleen; and RT-qPCR was used to detect the expression of related transcription factors in the spleen. Results IL-23p19 monoclonal antibody reduced urine protein levels, alleviated splenomegaly, improved renal function, and decreased anti-dsDNA antibody levels in MRL/lpr mice. It also mitigated glomerulonephritis and reduced renal immune complex deposition. Furthermore, IL-23p19 monoclonal antibody significantly suppressed the proportion of Th1 and Th17 cells while upregulating Treg cell proportion in the spleen. Additionally, it downregulated T-bet and retinoic acid receptor-related orphan receptor γt (RORγt) mRNA levels and upregulated forkhead box P3(FOXP3) mRNA levels in the spleen. Conclusions IL-23p19 monoclonal antibody demonstrates significant therapeutic effects in MRL/lpr mice, likely through modulation of the Th17/Treg cell balance.
Animals ; Female ; Mice, Inbred MRL lpr ; T-Lymphocytes, Regulatory/drug effects* ; Th17 Cells/drug effects* ; Antibodies, Monoclonal/therapeutic use* ; Interleukin-23 Subunit p19/immunology* ; Mice ; Lupus Nephritis/drug therapy* ; Kidney/drug effects* ; Antibodies, Antinuclear/blood*