OBJECTIVE: To explore the effect of human bone marrow mesenchymal stem cells (MSCs) with ectopic high OCT4 expression on T-cell proliferation, activation and secretion in vitro. METHODS: Peripheral blood mononuclear cells were isolated from healthy children. Anti-CD3 and anti-CD28 monoclonal antibodies were used to activate T lymphocytes, which were stimulated by interleukin (IL)-2 for one week in vitro. Then MSCs with ectopic high OCT4 expression (MSC-OCT4) were co-cultured with activated T lymphocytes. After one week of co-culture, the supernatant was collected and the levels of Th1/Th2 cytokines [IL-2, IL-4, IL-6, IL-10, tumor necrosis factor (TNF)-α and interferon (IFN)-γ] were determined by flow cytometry. The lymphocytes after one week of co-culture were collected and counted by Countstar software. After the proportions of activated/inactivated T cell subsets were determined by flow cytometry, the absolute lymphocyte counts were calculated and expressed as mean ± standard deviation. RESULTS: Compared with control T cell alone culture group, the proliferation of CD3⁺ T cells, CD3⁺CD4⁺ T cells, and CD3⁺CD8⁺ T cells were significantly inhibited in MSC group and MSC-OCT4 group. Compared with MSC, MSC-OCT4 could inhibit CD3⁺CD8⁺ T cell proliferation better (P =0.049), and mainly inhibited early T cell activation. Compared with control T cell alone culture group, the levels of IL-2 and INF-γ were significantly down-regulated both in MSC group and MSC-OCT4 group.After co-culture with T cells for one week, the level of IL-6 significantly increased in MSC group and MSC-OCT4 group compared with that before co-culture. Compared with control MSC group, MSC-OCT4 group had higher viable cell numbers after 1 week of co-culture (P =0.019), and could resist the inhibition of proliferation by higher concentration of mitomycin C. CONCLUSION Both MSC and MSC-OCT4 can inhibit the proliferation and activation of IL-2-stimulated T cells in vitro. After overexpression of OCT4, MSC has better proliferation ability in vitro and can inhibit the proliferation of CD3⁺CD8⁺ T cells more effectively, which may have a better and more lasting immunosuppressive ability to regulate the balance of Th1/Th2.
Child ; Humans ; Bone Marrow Cells ; CD8-Positive T-Lymphocytes/metabolism* ; Cell Proliferation ; Cells, Cultured ; Interleukin-2 ; Interleukin-6/metabolism* ; Leukocytes, Mononuclear/metabolism* ; Lymphocyte Activation ; Mesenchymal Stem Cells ; Tumor Necrosis Factor-alpha/metabolism*

OBJECTIVE: To investigate the effect of miR-125b on T cell activation in patients with aplastic anemia (AA) and its molecular mechanism. METHODS: A total of 30 AA patients were enrolled in department of hematology, Binzhou Medical University Hospital from January 2018 to October 2021, as well as 15 healthy individuals as healthy control (HC) group. Peripheral blood mononuclear cells (PBMCs) were isolated, in which the levels of miR-125b and B7-H4 mRNA were detected by RT-qPCR. Immunomagnetic beads were used to separate naive T cells and non-naive T cells from AA patients and healthy people to detect the levels of miR-125b and B7-H4 mRNA. Lentivirus LV-NC inhibitor and LV-miR-125b inhibitor were transfected into cells, and T cell activation was detected by flow cytometry. The dual-luciferase reporter gene assay was used to detect the targetting relationship between miR-125b and B7-H4. RT-qPCR and Western blot were used to detect the levels of miR-125b, CD40L, ICOS, IL-10 mRNA and B7-H4 protein. RESULTS: Compared with HC group, the expression of miR-125b was up-regulated but B7-H4 mRNA was down-regulated in PBMCs of AA patients (P <0.05), and the proportions of CD4⁺CD69⁺ T cells and CD8⁺CD69⁺ T cells in PBMCs of AA patients were higher (P <0.05). The expression of miR-125b was significantly up-regulated but B7-H4 mRNA was down-regulated in both naive T cells and non-naive T cells of AA patients (P <0.05), and non-naive T cells was more significant than naive T cells (P <0.05). Compared with NC inhibitor group, the expression of miR-125b was significantly decreased, the expression level of CD69 on CD4⁺ and CD8⁺ T cells in PBMCs was also significantly decreased, while the luciferase activity was significantly increased after co-transfection of miR-125b inhibitor and B7-H4-3'UTR-WT in the miR-125b inhibitor group (P <0.05). Compared with NC inhibitor group, the mRNA and protein levels of B7-H4 were significantly increased in the miR-125b inhibitor group (P <0.05). Compared with miR-125b inhibitor+shRNA group, the expression levels of CD69 on CD4⁺ and CD8⁺ T cells were significantly increased, and the levels of CD40L, ICOS and IL-10 mRNA were also significantly increased in the miR-125b inhibitor+sh-B7-H4 group (P <0.05). CONCLUSION MiR-125b may promote T cell activation by targetting B7-H4 in AA patients.
Humans ; Anemia, Aplastic/genetics* ; CD40 Ligand/metabolism* ; Interleukin-10 ; Leukocytes, Mononuclear/metabolism* ; Luciferases ; MicroRNAs/genetics* ; RNA, Messenger/metabolism* ; Lymphocyte Activation ; T-Lymphocytes/metabolism*

B cell receptor (BCR) is a key molecule involved in B cell specific recognition and the binding of antigens to produce adaptive humoral immune response. Gene rearrangement and high frequency mutation during B cell differentiation are the main mechanisms of BCR diversification. The enormous diversity and unique molecular structure of BCR determine the diversity and specificity of antigen recognition, shaping complex B cell repertoire with extensive collections of antigen specificities. Therefore, BCR antigen-specific information is vital to understanding the adaptive immune characteristics of different diseases. Our ability to connect BCR repertoire and antigen specificity has been enhanced with the development of B cell related research technologies, such as single cell sorting techniques, high-throughput sequencing (HTS), linking B cell receptor to antigen specificity through sequencing (LIBRA-seq). It could help researchers to better understand humoral immune responses, identify disease pathogenesis, monitor disease progression, design vaccines, and develop therapeutic antibodies and drugs. We summarizes recent studies on antigen-specific BCR of infections, vaccinations, autoimmune diseases and cancer. By analyzing autoantibody sequences of SLE as a case, the identification of autoantigens has become potentially possible due to this characterization.
Receptors, Antigen, B-Cell/metabolism* ; B-Lymphocytes/metabolism* ; Lymphocyte Activation ; High-Throughput Nucleotide Sequencing/methods*

OBJECTIVE: To analyze the changes in the gene expression profile of T cells in CML patients after TCRζ up-regulation expression, and to explore the molecular mechanism of T cell reactivation after transgenic up-regulation of TCRζ. METHODS: The peripheral blood mononuclear cells(PBMCs) from 3 newly untreated chronic-stage CML patients were collected, and the CD3 RESULTS: A total of 2248 differentially-expressed genes were obtained, including 553 up-regulated genes and 1695 down-regulated genes in experimental group as compared with those in control group (P<0.05) . The GO and KEGG enrichment analyses showed that differentially expressed genes involved in the biological processes related to T cell immune function, such as TCR signaling pathway, T cell proliferation and activation. Some of core genes involved in promoting the TCR signaling pathway, T cell proliferation, activation and apoptosis pathways were significantly up-regulated, while some core genes involved in inhibiting T cell activation were significantly down-regulated. CONCLUSION The molecular mechanism of the significantly improved T cell activation and proliferation ability in CML patients after TCRζ up-regulation may be related to the differential transcripts mediated signaling pathways of T cell activation, proliferation and apoptosis.
Humans ; Leukocytes, Mononuclear ; Lymphocyte Activation ; Receptors, Antigen, T-Cell/genetics* ; T-Lymphocytes ; Up-Regulation

BACKGROUND: Asbestos fibers possess tumorigenicity and are thought to cause mesothelioma. We have previously reported that exposure to asbestos fibers causes a reduction in antitumor immunity. Asbestos exposure in the mixed lymphocyte reaction (MLR) showed suppressed induction of cytotoxic T lymphocytes (CTLs), accompanied by a decrease in proliferation of CD8 METHODS: For MLR, human peripheral blood mononuclear cells (PBMCs) were cultured with irradiated allogenic PBMCs upon exposure to chrysotile B asbestos at 5 μg/ml for 7 days. After 2 days of culture, IL-15 was added at 1 ng/ml. After 7 days of MLR, PBMCs were collected and analyzed for phenotypic and functional markers of CD8 RESULTS: IL-15 addition partially reversed the decrease in CD3 CONCLUSION These findings indicate that CTLs induced upon exposure to asbestos possess dysfunctional machinery that can be partly compensated by IL-15 supplementation, and that IL-15 is more effective in the recovery of proliferation and granzyme B levels from asbestos-induced suppression of CTL induction compared with IL-2.
Asbestos/adverse effects* ; CD8-Positive T-Lymphocytes/metabolism* ; Humans ; Interleukin-15/pharmacology* ; Lymphocyte Activation/immunology* ; T-Lymphocytes, Cytotoxic/metabolism*

OBJECTIVES: To explore the characteristics of immune function of healthy full-term infants at the age of 3 months, and to analyze the relationship of immune function with feeding pattern and sex. METHODS: A total of 84 healthy full-term infants born in four hospitals in Beijing and Hohhot, China were prospectively recruited. Their feeding patterns remained unchanged within 4 months after birth. They were divided into a breast-feeding group and a milk powder feeding group according to their feeding patterns. At the age of 3 months after birth, peripheral venous blood samples of the two groups were collected to evaluate cellular immunity and humoral immunity and perform routine blood test. The laboratory indices were compared between infants with different feeding patterns and sexes. RESULTS: Compared with the milk powder feeding group, the breast-feeding group had significantly lower proportion of T cell second signal receptor CD28, immunoglobulin M, and proportion and absolute count of neutrophils ( CONCLUSIONS Sex has no significant effect on the proportion of lymphocyte subsets in 3-month-old full-term infants, but feeding patterns are associated with the proportion of CD28
Breast Feeding ; CD8-Positive T-Lymphocytes ; Female ; HLA-DR Antigens ; Humans ; Infant ; Lymphocyte Activation ; Male ; Prospective Studies

Cytokine-activated T cells (CATs) can be easily expanded and are widely applied to cancer immunotherapy. However, the good efficacy of CATs is rarely reported in clinical applications because CATs have no or very low antigen specificity. The low-efficacy problem can be resolved using T cell antigen receptor-engineered CAT (TCR-CAT). Herein, we demonstrate that NY-ESO-1 HLA-A*02:01-specific high-affinity TCR (HAT)-transduced CATs can specifically kill cancer cells with good efficacy. With low micromolar range dissociation equilibrium constants, HAT-transduced CATs showed good specificity with no off-target killing. Furthermore, the high-affinity TCR-CATs delivered significantly better activation and cytotoxicity than the equivalent TCR-engineered T cells (TCR-Ts) in terms of interferon-γ and granzyme B production and in vitro cancer cell killing ability. TCR-CAT may be a very good alternative to the expensive TCR-T, which is considered an effective personalized cyto-immunotherapy.
Cell Line, Tumor ; Cytokines ; metabolism ; Cytotoxicity, Immunologic ; Genetic Engineering ; HLA-A2 Antigen ; metabolism ; Humans ; Immunotherapy, Adoptive ; methods ; Lymphocyte Activation ; Receptors, Antigen, T-Cell ; genetics ; immunology ; T-Lymphocytes ; immunology

OBJECTIVE: To investigate the effect of sputum ubiquitin ligase (Cbl-b) gene known-down on the cytotoxicity of H9 T lymphocytes against human laryngeal squamous cancer Hep-2 cells and explore the underlying mechanism. METHODS: CD4 T lymphocytes isolated from 12 patients with laryngeal squamous carcinoma and 12 healthy individuals were examined for Cbl-b mRNA expressions using RT-PCR. H9 T lymphocytes cultured in 96-well plates were transfected with Cbl-b siRNA via liposomes followed by treatment with an anti-IL-2 monoclonal antibody, with H9 T lymphocytes transfected with a scrambled sequence as the negative control. The expressions of Cbl-b mRNA and protein in the cells were detected using real-time fluorescent quantitative PCR and Western blotting, respectively. The killing effect of the treated T lymphocytes against Hep-2 cells was assessed using the cell counting kit (CCK-8). The positive expression rates of CD69 and CD25 on the surface of H9 T lymphocytes were determined using flow cytometry, and the levels of interleukin-2 (IL-2) and interferon-gamma (INF-γ) in the culture supernatants of H9 T lymphocytes were detected with ELISA. RESULTS: The CD4 T lymphocytes from patients with laryngeal squamous carcinoma showed significantly increased Cbl-b mRNA level compared with those from healthy individuals ( < 0.05). Transfection of H9 T lymphocytes with Cbl-b siRNA significantly reduced the expression levels of Cbl-b mRNA and protein ( < 0.05), which were not significantly affected by subsequent treatment of the cells with the anti-IL-2 antibody (>0.05). At different target-effector ratios, the Cbl-b siRNA-transfected cells showed significantly higher Hep-2 cell killing rates and higher positivity rates of CD69 and CD25 expressions than the blank and negative control cells and the cells with both Cbl-b siRNA transfection and anti-IL-2 treatment ( < 0.05). Cbl-b silencing in H9 T lymphocytes resulted in significantly increased levels of IL-2 and INF-γ in the supernatant as compared with those in the blank and negative control groups ( < 0.05). CONCLUSIONS Cbl-b gene silencing effectively enhances the killing effect of H9 T lymphocytes against Hep-2 cells probably as the result of enhanced IL-2 secretion and T lymphocyte activation.
Carcinoma, Squamous Cell ; genetics ; therapy ; Gene Silencing ; Humans ; Laryngeal Neoplasms ; genetics ; therapy ; Lymphocyte Activation ; RNA, Small Interfering ; T-Lymphocytes

Antiepileptic drugs (AEDs) can induce severe cutaneous adverse reactions (SCARs) such as Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome. We performed HLA genotyping and lymphocyte activation tests (LATs) for five AED-induced SCAR patients (three males and two females; aged 40–66 years old). Three patients were treated with carbamazepine (CBZ) for pain control, one was treated with phenytoin (PHT) for seizure prevention, and one was treated with valproic acid (VPA) for seizure prevention. One patient was diagnosed with CBZ-induced DRESS syndrome and the remaining patients were diagnosed with SJS. All patients recovered from SCARs after stopping suspicious drugs and supportive care. LATs were conducted to confirm the culprit drug responsible for inducing SCARs; and LAT results were positive for the suspected culprit drugs, in all except in one case. HLA-A,
Alleles ; Anticonvulsants ; Carbamazepine ; Cicatrix ; Drug Hypersensitivity Syndrome ; Female ; HLA-A Antigens ; Humans ; Long-Acting Thyroid Stimulator ; Lymphocyte Activation ; Lymphocytes ; Male ; Methods ; Phenytoin ; Seizures ; Stevens-Johnson Syndrome ; Valproic Acid

The activation mechanism of chimeric antigen receptor (CAR)-engineered T cells may differ substantially from T cells carrying native T cell receptor, but this difference remains poorly understood. We present the first comprehensive portrait of single-cell level transcriptional and cytokine signatures of anti-CD19/4-1BB/CD28/CD3ζ CAR-T cells upon antigen-specific stimulation. Both CD4 helper T (T) cells and CD8 cytotoxic CAR-T cells are equally effective in directly killing target tumor cells and their cytotoxic activity is associated with the elevation of a range of T1 and T2 signature cytokines, e.g., interferon γ, tumor necrotic factor α, interleukin 5 (IL5), and IL13, as confirmed by the expression of master transcription factor genes TBX21 and GATA3. However, rather than conforming to stringent T1 or T2 subtypes, single-cell analysis reveals that the predominant response is a highly mixed T1/T2 function in the same cell. The regulatory T cell activity, although observed in a small fraction of activated cells, emerges from this hybrid T1/T2 population. Granulocyte-macrophage colony stimulating factor (GM-CSF) is produced from the majority of cells regardless of the polarization states, further contrasting CAR-T to classic T cells. Surprisingly, the cytokine response is minimally associated with differentiation status, although all major differentiation subsets such as naïve, central memory, effector memory, and effector are detected. All these suggest that the activation of CAR-engineered T cells is a canonical process that leads to a highly mixed response combining both type 1 and type 2 cytokines together with GM-CSF, supporting the notion that polyfunctional CAR-T cells correlate with objective response of patients in clinical trials. This work provides new insights into the mechanism of CAR activation and implies the necessity for cellular function assays to characterize the quality of CAR-T infusion products and monitor therapeutic responses in patients.
Antigens ; metabolism ; CTLA-4 Antigen ; metabolism ; Cell Differentiation ; drug effects ; Cell Line ; Cytokines ; metabolism ; Cytotoxicity, Immunologic ; drug effects ; Granulocyte-Macrophage Colony-Stimulating Factor ; pharmacology ; Humans ; Lymphocyte Activation ; drug effects ; immunology ; Lymphocyte Subsets ; drug effects ; metabolism ; Phenotype ; Proteomics ; Receptors, Chimeric Antigen ; metabolism ; Single-Cell Analysis ; methods ; T-Lymphocytes, Regulatory ; drug effects ; metabolism ; Th1 Cells ; cytology ; drug effects ; Th2 Cells ; cytology ; drug effects ; Transcription, Genetic ; drug effects ; Up-Regulation ; drug effects