OBJECTIVE: To investigate the expression of co-inhibitory molecules TIGIT/CD155 and PD-1 on CD4⁺T cells and Treg cells in peripheral blood of patients with chronic lymphocytic leukemia (CLL) and analyze their clinical significance. METHODS: The expression of PD-1 and TIGIT on CD4⁺T cells and Treg cells was detected by flow cytometry in 40 CLL patients and 20 healthy controls. Additionally, the expression of CD155 on peripheral blood B cells and DC cells of the enrolled subjects was detected. RESULTS: The proportions of PD-1⁺TIGIT⁺CD4⁺T cells, PD-1⁺TIGIT⁺Treg cells and CD155⁺DC cells in peripheral blood of CLL patients were significantly higher than those of healthy controls ( P < 0.05). The proportions of PD-1⁺TIGIT⁺CD4⁺T cells and PD-1⁺TIGIT⁺Treg cells in CLL patients were significantly higher than those of PD-1⁺TIGIT^-CD4⁺T cells and PD-1⁺TIGIT^-Treg cells, respectively ( P < 0.05). Both PD-1⁺TIGIT⁺CD4⁺T cells and PD-1⁺TIGIT⁺Treg cells were positively correlated with the level of CD155⁺DC cells (r =0.742, r =0.766). With the progression of Binet stage, the proportions of PD-1⁺TIGIT⁺CD4⁺T cells, PD-1⁺TIGIT⁺Treg cells, and CD155⁺DC cells gradually increased ( P < 0.05), and the aforementioned three types cells were all increased in patients with CD38≥30%, IGVH unmutated, or poor prognosis due to chromosomal abnormalities ( P < 0.05). CONCLUSION Co-inhibitory molecules PD-1 and TIGIT may be involved in immunodepletion in patients with advanced CLL, which has clinical prognostic value. Dual inhibitor molecular targeted therapy provides a new direction for the individualized treatment of CLL.
Humans ; Leukemia, Lymphocytic, Chronic, B-Cell/immunology* ; Receptors, Immunologic/metabolism* ; Programmed Cell Death 1 Receptor/metabolism* ; T-Lymphocytes, Regulatory/metabolism* ; Receptors, Virus/metabolism* ; CD4-Positive T-Lymphocytes/metabolism* ; Male ; Female ; Middle Aged ; Flow Cytometry ; Clinical Relevance

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

Multiple sclerosis (MS) is a neuroinflammatory demyelinating disease, mediated by pathogenic T helper 17 (Th17) cells. However, the therapeutic effect is accompanied by the fluctuation of the proportion and function of Th17 cells, which prompted us to find the key regulator of Th17 differentiation in MS. Here, we demonstrated that the triggering receptor expressed on myeloid cells 2 (TREM-2), a modulator of pattern recognition receptors on innate immune cells, was highly expressed on pathogenic CD4-positive T lymphocyte (CD4⁺ T) cells in both patients with MS and experimental autoimmune encephalomyelitis (EAE) mouse models. Conditional knockout of Trem-2 in CD4⁺ T cells significantly alleviated the disease activity and reduced Th17 cell infiltration, activation, differentiation, and inflammatory cytokine production and secretion in EAE mice. Furthermore, with Trem-2 knockout in vivo experiments and in vitro inhibitor assays, the TREM-2/zeta-chain associated protein kinase 70 (ZAP70)/signal transducer and activator of transcription 3 (STAT3) signal axis was essential for Th17 activation and differentiation in EAE progression. In conclusion, TREM-2 is a key regulator of pathogenic Th17 in EAE mice, and this sheds new light on the potential of this therapeutic target for MS.
Animals ; Humans ; Mice ; CD4-Positive T-Lymphocytes/pathology* ; Cell Differentiation ; Encephalomyelitis, Autoimmune, Experimental/metabolism* ; Mice, Inbred C57BL ; Multiple Sclerosis ; Th1 Cells/pathology*

Objective To clarify the mechanism that HIV infection mediates mitochondrial damage of CD4⁺ T lymphocytes (CD4⁺ T cells) through mitogen-activated protein kinase (MAPK) pathway. Methods From October 1st, 2022 to March 31st, 2023, 47 HIV-infected people who received antiretroviral therapy (ART) for 4 years were recruited, including 22 immune non-responders (INR) and 25 responders (IR); and 26 sex and age-matched control participants (HC) who were negative for HCV, HBV, and HIV infections. The immune parameters were analyzed by flow cytometry. Finally, peripheral blood mononuclear cells (PBMCs) from HC or HIV patients were treated with MAPK pathway inhibitor SB203580, and the changes of mitochondrial function of CD4⁺ T cells were observed. Results Compared with HC group, the proportion of CD4⁺ T cells in PBMCs in INR group and IR group was significantly lower, and the proportion of CD4⁺ T cells in PBMCs in INR group was significantly lower than that in IR group. In addition, the proportion of naive (CD45RA⁺CD27⁺)T cells in PBMCs in INR group was significantly lower than that in HC group and IR group. Compared with HC group and IR group, the proportions of CD4⁺PD-1⁺, CD4⁺Av⁺ and CD4⁺MO⁺ in PBMCs in INR group and the proportions of CD45RA⁺CD27⁺PD-1⁺, CD45RA⁺CD27⁺Av⁺, CD45RA⁺CD27⁺MO⁺ in CD4⁺ T cell subsets increased significant. Compared with HC-con group, the basal respiration, maximal respiration and adenosine triphosphate(ATP) production of CD4⁺ T cells in HIV-con group decreased significantly, and JC-1 (green/red) in CD4⁺ T cells increased significantly. Compared with HIV-con group, the basal respiration, maximal respiration, ATP production and respiratory potential of CD4⁺ T cells in HIV-SB203580 group increased significantly, and the JC-1 (green/red) in CD4⁺ T cells decreased significantly. Conclusion Abnormal activation of the MAPK signaling pathway is observed in HIV patients receiving ART treatment, especially in CD4⁺ T cells of INR patients, which may lead to impaired mitochondrial function and abnormal CD4⁺ T cell homeostasis.
Humans ; HIV Infections/immunology* ; Male ; Mitochondria/drug effects* ; Female ; CD4-Positive T-Lymphocytes/metabolism* ; Adult ; Middle Aged ; MAP Kinase Signaling System/drug effects* ; Pyridines/pharmacology* ; Imidazoles/pharmacology* ; Leukocytes, Mononuclear/immunology*

OBJECTIVES: To explore the prophylactic and therapeutic effects of Alhagi maurorum ethanolic extract (AME) in concanavalin A (Con A)-induced hepatitis (CIH) as well as possible underlying mechanisms. METHODS: Polyphenols in AME were characterized using high performance liquid chromatography (HPLC). Swiss albino mice were divided into 4 groups. Normal group received intravenous phosphate-buffered saline (PBS); Con A group received 40 mg/kg intravenous Con A. Prophylaxis group administered 300 mg/(kg·d) AME orally for 5 days before Con A intervention. Treatment group received intravenous Con A then administered 300 mg/kg AME at 30 min and 3 h after Con A intervention. After 24 h of Con A injection, hepatic injury, oxidative stress, and inflammatory mediators were assessed. Histopathological examination and markers of apoptosis, inflammation, and CD4⁺ cell infiltration were also investigated. RESULTS: HPLC analysis revealed that AME contains abundant polyphenols with pharmacological constituents, such as ellagic acid, gallic acid, ferulic acid, methylgallate, and naringenin. AME alleviated Con A-induced hepatic injury, as manifested by a significant reduction in alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase (P<0.01). Additionally, the antioxidant effect of AME was revealed by a significant reduction in oxidative stress markers (nitric oxide and malondialdehyde) and restored glutathione (P<0.01). The levels of proinflammatory cytokines (tumor necrosis factor-α, interferon-γ, and interleukin-6) and c-Jun N-terminal kinase (JNK) activity were reduced (P<0.01). Histopathological examination of liver tissue showed that AME significantly ameliorated necrotic and inflammatory lesions induced by Con A (P<0.01). Moreover, AME reduced the expression of nuclear factor kappa B, pro-apoptotic protein (Bax), caspase-3, and CD4⁺ T cell hepatic infiltration (P<0.01). The expression of anti-apoptotic protein Bcl-2 was increased (P<0.01). CONCLUSION AME has hepatoprotective and ameliorative effects in CIH mice. These beneficial effects are likely due to the anti-inflammatory, antioxidant, and anti-apoptotic effects of the clinically important polyphenolic content. AME could be a novel and promising hepatoprotective agent for managing immune-mediated hepatitis.
Animals ; Concanavalin A ; Mice ; Polyphenols/pharmacology* ; Liver/drug effects* ; Plant Extracts/therapeutic use* ; Camelus ; Oxidative Stress/drug effects* ; Male ; Protective Agents/pharmacology* ; Chemical and Drug Induced Liver Injury/prevention & control* ; Apoptosis/drug effects* ; Hepatitis/pathology* ; Antioxidants/pharmacology* ; CD4-Positive T-Lymphocytes/drug effects* ; Inflammation Mediators/metabolism*

Nucleolar complex associated 4 homolog (NOC4L) is a key factor in ribosome biogenesis, and this study aims to investigate its roles in activated T cells from the perspective of translation regulation. Firstly, flow cytometry was employed to determine the expression levels of NOC4L in the CD4⁺ T cells under different conditions in the transgenic reporter mice expressing Noc4l^mCherry. Subsequently, the expression of NOC4L along with cell proliferation was examined under Th1 and Th17 polarization conditions. Finally, in vitro experiments were conducted to identify the proteins interacting with NOC4L during the activation of Th1 and Th17 cells, on the basis of which the potential mechanisms of NOC4L were explored. The results showed that the expression level of NOC4L increased in activated CD4⁺ T cells, and the expression of NOC4L was closely associated with the proliferation and division of activated T cells. The in vitro experiments revealed interactions between NOC4L and proteins involved in ribosome assembly and cell proliferation during T cell activation. These findings lay a foundation for probing into the post-transcriptional regulation in helper T cells and hold profound significance for understanding the activation and regulatory mechanisms of T cells.
Animals ; Mice ; Lymphocyte Activation ; Cell Proliferation ; Mice, Transgenic ; Nuclear Proteins/genetics* ; Th1 Cells/immunology* ; Th17 Cells/metabolism* ; CD4-Positive T-Lymphocytes/immunology* ; Ribosomes/metabolism*

BACKGROUND: Previous studies have examined the bulk transcriptome of peripheral blood immune cells in acquired immunodeficiency syndrome patients experiencing immunological non-responsiveness. This study aimed to investigate the characteristics of specific immune cell subtypes in acquired immunodeficiency syndrome patients who exhibit immunological non-responsiveness. METHODS: A single-cell transcriptome sequencing of peripheral blood mononuclear cells obtained from both immunological responders (IRs) (CD4 + T-cell count >500) and immunological non-responders (INRs) (CD4 + T-cell count <300) was conducted. The transcriptomic profiles were used to identify distinct cell subpopulations, marker genes, and differentially expressed genes aiming to uncover potential genetic factors associated with immunological non-responsiveness. RESULTS: Among the cellular subpopulations analyzed, the ratios of monocytes, CD16 + monocytes, and exhausted B cells demonstrated the most substantial differences between INRs and IRs, with fold changes of 39.79, 11.08, and 2.71, respectively. In contrast, the CD4 + T cell ratio was significantly decreased (0.39-fold change) in INRs compared with that in IRs. Similarly, the ratios of natural killer cells and terminal effector CD8 + T cells were also lower (0.37-fold and 0.27-fold, respectively) in the INRs group. In addition to several well-characterized immune cell-specific markers, we identified a set of 181 marker genes that were enriched in biological pathways associated with human immunodeficiency virus (HIV) replication. Notably, ISG15 , IFITM3 , PLSCR1 , HLA-DQB1 , CCL3L1 , and DDX5 , which have been demonstrated to influence HIV replication through their interaction with viral proteins, emerged as significant monocyte marker genes. Furthermore, the differentially expressed genes in natural killer cells were also enriched in biological pathways associated with HIV replication. CONCLUSIONS We generated an atlas of immune cell transcriptomes in HIV-infected IRs and INRs. Host genes associated with HIV replication were identified as markers of, and were found to be differentially expressed in, different types of immune cells.
Humans ; Acquired Immunodeficiency Syndrome ; Transcriptome/genetics* ; HIV ; HIV Infections/genetics* ; Leukocytes, Mononuclear/metabolism* ; CD4-Positive T-Lymphocytes/metabolism* ; Virus Replication ; Membrane Proteins/metabolism* ; RNA-Binding Proteins/metabolism*

Humans ; CD4-Positive T-Lymphocytes/metabolism* ; CD8-Positive T-Lymphocytes/metabolism* ; HIV Infections/drug therapy* ; HIV-1

This study aims to investigate the effect of anti-PD-1 antibody expressed in mouse mammary gland on the surface antigen protein of spleen T cells, cytokine expression, spleen CD4⁺ T cell proliferation and proliferation related pathways of transgenic mice at the cellular level. Transgenic mice expressing anti-human PD-1 antibody at 8 weeks of age without pregnancy and 18 weeks of age with lactation were divided into two groups, with transgenic negative mice in each group as the control. Spleen lymphocytes were extracted and the changes of spleen lymphocytes were detected. Compared with transgenic negative mice, the proportion of effector T cells of spleen T cells in the immune system of transgenic mice with anti-PD-1 antibody expressed in breast increased, the proportion of Treg cells decreased, and the IFN-γ, IL-17 and IL-2 expressed in CD4⁺ T cells increased in varying degrees. Moreover, IL-4, IL-10 and TGF-β in CD4⁺ T cells did not change, nor did some cell surface protein molecules related to T cell stimulate. There was no significant difference in T cell proliferation between transgenic positive and transgenic negative mice. In transgenic positive mice, the expression of phosphorylated proteins in PI3K/Akt/mTOR and RAS/MEK/ERK pathways were partially up-regulated, but the whole pathway was not completely up-regulated. Therefore, it is feasible to use transgenic mice as host to express monoclonal antibodies related to immune system such as anti-PD-1 antibody.
Mice ; Animals ; Female ; Mice, Transgenic ; Spleen/metabolism* ; CD4-Positive T-Lymphocytes/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Cytokines/metabolism*

This study aims to develop a method to detect bovine multi-cytokines based on flow cytometry. Previously we have prepared and screened monoclonal antibodies against bovine cytokines IFN-γ, IL-2, TNF-α, IP-10 and MCP-1. These bovine cytokine monoclonal antibodies were fluorescently labeled, and the combination of antibody and cell surface molecules were used to develop the method for detecting bovine multi-cytokines. Subsequently, the developed method was used to determine the cytokine expression profile of Mycobacterium bovis BCG infected bovine peripheral blood mononuclear cells in vitro, and evaluate the cytokine expression level of peripheral blood CD4⁺ T cells of tuberculosis-positive cattle. The bovine multi-cytokine flow cytometry detection method can effectively determine the cytokine expression of BCG-infected bovine peripheral blood T lymphocytes. Among them, the expression levels of IFN-γ, IL-2, and TNF-α continue to increase after 40 hours of infection, while the expression levels of IP-10 and MCP-1 decreased. The combined detection of IFN-γ, IL-2, and TNF-α on CD4⁺ T lymphocytes in peripheral blood of cattle can effectively distinguish tuberculosis-positive and tuberculosis-negative samples. This method may facilitate evaluating the level of cellular immune response after bovine pathogen infection and vaccine injection.
Cattle ; Animals ; Cytokines ; BCG Vaccine/metabolism* ; Tumor Necrosis Factor-alpha/metabolism* ; Interleukin-2 ; Flow Cytometry/methods* ; Chemokine CXCL10/metabolism* ; Leukocytes, Mononuclear ; CD4-Positive T-Lymphocytes/metabolism* ; Tuberculosis ; Antibodies, Monoclonal/metabolism*