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*

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

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

Novel biologics that redirect cytotoxic T lymphocytes (CTLs) to kill tumor cells bearing a tumor associated antigen hold great promise in the clinic. However, the ability to safely and potently target CD3 on CTL toward tumor associated antigens (TAA) expressed on tumor cells remains a challenge of both technology and biology. Herein we describe the use of a Half DVD-Ig format that can redirect CTL to kill tumor cells. Notably, Half DVD-Ig molecules that are monovalent for each specificity demonstrated reduced non-specific CTL activation and conditional CTL activation upon binding to TAA compared to intact tetravalent DVD-Ig molecules that are bivalent for each specificity, while maintaining good drug like properties and appropriate PK properties.
Animals ; Antibodies, Bispecific ; immunology ; Antibodies, Monoclonal ; immunology ; pharmacokinetics ; CD3 Complex ; metabolism ; Cell Line, Tumor ; Cytotoxicity, Immunologic ; ErbB Receptors ; metabolism ; Female ; Humans ; Lymphocyte Activation ; immunology ; Mice, SCID ; Neoplasms ; immunology ; pathology ; Rats, Sprague-Dawley ; T-Lymphocytes, Cytotoxic ; immunology

Chimeric antigen receptor (CAR) T cell therapy is a promising cancer treatment that has recently been undergoing rapid development. However, there are still some major challenges, including precise tumor targeting to avoid off-target or "on-target/off-tumor" toxicity, adequate T cell infiltration and migration to solid tumors and T cell proliferation and persistence across the physical and biochemical barriers of solid tumors. In this review, we focus on the primary challenges and strategies to design safe and effective CAR T cells, including using novel cutting-edge technologies for CAR and vector designs to increase both the safety and efficacy, further T cell modification to overcome the tumor-associated immune suppression, and using gene editing technologies to generate universal CAR T cells. All these efforts promote the development and evolution of CAR T cell therapy and move toward our ultimate goal-curing cancer with high safety, high efficacy, and low cost.
Cell Movement ; immunology ; Cell Proliferation ; Gene Expression ; Genetic Vectors ; chemistry ; metabolism ; Humans ; Immunotherapy, Adoptive ; methods ; Lymphocyte Activation ; Lymphocytes, Tumor-Infiltrating ; cytology ; immunology ; transplantation ; Neoplasms ; genetics ; immunology ; pathology ; therapy ; Patient Safety ; Receptors, Antigen, T-Cell ; chemistry ; genetics ; immunology ; Recombinant Fusion Proteins ; chemistry ; genetics ; immunology ; Signal Transduction ; Single-Chain Antibodies ; chemistry ; genetics ; T-Lymphocytes ; cytology ; immunology ; transplantation ; Treatment Outcome

To explore the association between T-cell receptor beta variable (TCR BV) complementarity determining region 3 (CDR3) spectratyping and CMV activation in the recipients of allogeneic hematopoietic stem cell transplantation (HSCT).Fluorescence quantitative PCR melting curve analysis was used to sequence 24 TCR BV families in 7 HSCT recipients and 3 healthy controls. CMV-pp65 antigenemia was measured by immunohistochemical staining. Plasma IgM specific for CMV was identified using ELISA. Relationship between TCR BV families and CMV activation was statistically analyzed.Twenty-four TCR BV families were expressed in 3 healthy controls, while TCR BV CDR3 sequencing results in 7 recipients turned out to be BV9, BV11, BV17, BV20 and so on. Amino acid sequence features were as follows:TCR BV9 contained "QVRGGTDTQ", TCR BV11 contained "VATDEQ" and "LGDEQ", TCR BV17 contained "IGQGNTEA", and TCR BV20 contained "VGLAANEQ". Five recipients suffered from pp65 antigenemia in 3 month after transplantation, and pp65-positive cells ranged from 2 to 15 per 5×10white blood cells. Three recipients were CMV-IgM positive. No significant differences were found in TCR BV families between pp65-positive recipients and pp65-negative recipients (all>0.05). But there was statistically significant difference in frequency of TCR BV11 between CMV-IgM negative recipients and CMV-IgM positive recipients (<0.05).T cell immune response was characterized by special TCR BV CDR3 spectratyping in HSCT recipients, and TCR BV11 expression may be associated with CMV activation.
Amino Acid Sequence ; Complementarity Determining Regions ; genetics ; immunology ; Cytomegalovirus ; genetics ; immunology ; Cytomegalovirus Infections ; genetics ; Genotype ; Hematopoietic Stem Cell Transplantation ; adverse effects ; Humans ; Lymphocyte Activation ; genetics ; Phosphoproteins ; Polymerase Chain Reaction ; Polymorphism, Genetic ; immunology ; Receptors, Antigen, T-Cell, alpha-beta ; genetics ; immunology ; Spleen ; T-Lymphocytes ; immunology ; virology ; Viral Matrix Proteins

In allogeneic transplantation, including the B6 anti-BALB.B settings, H60 and H4 are two representative dominant minor histocompatibility antigens that induce strong CD8 T-cell responses. With different distribution patterns, H60 expression is restricted to hematopoietic cells, whereas H4 is ubiquitously expressed. H60-specific CD8 T-cell response has been known to be dominant in most cases of B6 anti-BALB.B allo-responses, except in the case of skin transplantation. To understand the mechanism underlying the subdominance of H60 during allogeneic skin transplantation, we investigated the dynamics of the H60-specific CD8 T cells in B6 mice transplanted with allogeneic BALB.B tail skin. Unexpectedly, longitudinal bioluminescence imaging and flow cytometric analyses revealed that H60-specific CD8 T cells were not always subdominant to H4-specific cells but instead showed a brief dominance before the H4 response became predominant. H60-specific CD8 T cells could expand in the draining lymph node and migrate to the BALB.B allografts, indicating their active participation in the anti-BALB.B allo-response. Enhancing the frequencies of H60-reactive CD8 T cells prior to skin transplantation reversed the immune hierarchy between H60 and H4. Additionally, H60 became predominant when antigen presentation was limited to the direct pathway. However, when antigen presentation was restricted to the indirect pathway, the expansion of H60-specific CD8 T cells was limited, whereas H4-specific CD8 T cells expanded significantly, suggesting that the temporary immunodominance and eventual subdominance of H60 could be due to their reliance on the direct antigen presentation pathway. These results enhance our understanding of the immunodominance phenomenon following allogeneic tissue transplantation.
Animals ; Antigen Presentation ; Antigen-Presenting Cells/immunology/metabolism ; CD8-Positive T-Lymphocytes/*immunology ; Epitopes, T-Lymphocyte/*immunology ; Female ; Graft Rejection/*immunology ; Interferon-gamma ; Lymphocyte Activation/immunology ; Lymphocyte Count ; Mice ; Minor Histocompatibility Antigens/*immunology/metabolism ; *Skin Transplantation ; Transplantation, Homologous

Cancer cells and the immune system are closely related and thus influence each other. Although immune cells can suppress cancer cell growth, cancer cells can evade immune cell attack via immune escape mechanisms. Natural killer (NK) cells kill cancer cells by secreting perforins and granzymes. Upon contact with cancer cells, NK cells form immune synapses to deliver the lethal hit. Mature NK cells are differentiated from hematopoietic stem cells in the bone marrow. They move to lymph nodes, where they are activated through interactions with dendritic cells. Interleukin-15 (IL-15) is a key molecule that activates mature NK cells. The adoptive transfer of NK cells to treat incurable cancer is an attractive approach. A certain number of activated NK cells are required for adoptive NK cell therapy. To prepare these NK cells, mature NK cells can be amplified to obtain sufficient numbers of NK cells. Alternatively, NK cells can be differentiated and amplified from hematopoietic stem cells. In addition, the selection of donors is important to achieve maximal efficacy. In this review, we discuss the overall procedures and strategies of NK cell therapy against cancer.
Cell Differentiation ; *Cell- and Tissue-Based Therapy ; Gene Expression Regulation ; Hematopoietic Stem Cells/cytology/metabolism ; Humans ; *Immunotherapy, Adoptive ; Killer Cells, Natural/cytology/*immunology/*metabolism ; Lymphocyte Activation/immunology ; Signal Transduction

The defectiveness of bone marrow mesenchymal stem cells (BM-MSCs) in acquired aplastic anemia (AA) has been a frequent research topic in recent years. This review summarizes the defectiveness of BM-MSCs which is responsible for the mechanism of acquired AA and the prospective application of BM-MSCs in the treatment of acquired AA. An increasingly number of laboratory statistics has demonstrated that the defectiveness of BM-MSCs is more likely to play an important role in the pathogenesis of AA, namely, the apparently different biological characteristics and gene expression profiles, the decreased ability of supporting hematopoiesis as well as self-renewal and differentiation, and the exhaustion of regulating immune response of hematopoietic environment. Those abnormalities continuously prompt AA to become irreversible bone marrow failure along with the imbalanced immunity. With deepening research on MSCs, infusion of MSCs for the primary purpose of recovering hematopoietic microenvironment may become a new approach for the treatment of AA.
Anemia, Aplastic ; etiology ; immunology ; therapy ; Bone Marrow ; Cell Differentiation ; Cell Proliferation ; Cytokines ; analysis ; Humans ; Lymphocyte Activation ; Mesenchymal Stem Cell Transplantation ; Mesenchymal Stromal Cells ; physiology ; T-Lymphocytes, Regulatory ; immunology

OBJECTIVETo study the roles of PKCα on the proliferation, apoptosis, differentiation, cytokine production and inducible regulatory T cell (iTreg) induction of T cells.

METHODST cells from WT (PKCα⁺/⁺) or PKCα knockout (PKCα⁻/⁻) mice were isolated and cultured in vitro. T cell proliferation and apoptosis were determined using ³H thymidine incorporation and CSFE/Annexin V staining. Cytokines production (IL-2, IL-4, IFN-γ and IL-17) was detected using ELISA. CD4⁺T cells were isolated and cultured in vitro via Th17 or iTreg biased condition. Flow cytometry was used to detect the cell differentiation.

RESULTSThe production of IL-2 upon TCR stimulation increased, while the contents of IL-4 and IL-17 decreased in the PKCα⁻/⁻ group compared with the PKCα⁺/⁺ group. The differentiation rate of Th17 cells decreased, while the iTreg production increased in the PKCα⁻/⁻ group compared with the PKCα⁺/⁺ group.

CONCLUSIONSPKC-α is proinflammatory.

Animals ; Cell Differentiation ; Cytokines ; biosynthesis ; Lymphocyte Activation ; Mice ; Protein Kinase C-alpha ; physiology ; Receptors, Antigen, T-Cell ; physiology ; T-Lymphocytes ; physiology ; Th17 Cells ; immunology