scholarly journals Protection from anti-TCR/CD3-induced apoptosis in immature thymocytes by a signal through thymic shared antigen-1/stem cell antigen-2.

1996 ◽  
Vol 183 (5) ◽  
pp. 2355-2360 ◽  
Author(s):  
S Noda ◽  
A Kosugi ◽  
S Saitoh ◽  
S Narumiya ◽  
T Hamaoka
Keyword(s):  
T Cells ◽  
Stem Cell ◽  
T Cell ◽  
Activated T Cells ◽  
Cell Surface Molecule ◽  
Newborn Mice ◽  
Cell Antigen ◽  
Peripheral T Cells ◽  
Induced Apoptosis

During T cell development in the thymus, the expression of thymic shared antigen-1 (TSA-1)/stem cell antigen-2 (Sca-2), a glycosylphosphatidylinositol (GPI)-anchored differentiation antigen, is developmentally regulated. The expression level of TSA-1 is the highest in most immature CD4- CD8- thymocytes, high in CD4+ CD8+ thymocytes, but barely detectable in mature CD4+ CD8- or CD4- CD8- thymocytes and peripheral T cells. We have previously shown that surface TSA-1 expression in peripheral T cells is induced upon activation and that anti-TSA-1 mAb inhibits the T cell receptor (TCR) signaling pathway in activated T cells. In the present study, we have analyzed a role of TSA-1 in thymic selection events, especially in TCR-mediated apoptosis. In in vitro experiments, anti-TSA-1 blocked anti-CD3-induced cell death of T cell hybridomas. When anti-TSA-1 was injected into newborn mice in vivo together with anti-CD3 epsilon or anti-TCR-beta, TCR/CD3-mediated apoptosis of thymocytes was almost completely blocked. The blockade of apoptosis was defined by the inhibition of, first, the decrease in total number of thymocytes; second, the decrease in percentages of CD4+ CD8+ thymocytes; and third, the induction of DNA fragmentation. However, anti-TSA-1 did not block either steroid- or radiation-induced apoptosis, indicating that a signal via TSA-1 does not inhibit a common pathway of thymocyte apoptosis. Since TCR-mediated apoptosis is pivotal in thymic ontogeny, these results suggest that TSA-1/Sca-2 is an important cell surface molecule regulating the fate of a developing T cell.

Activated T Cell-Mediated Immunotherapy with a Chimeric Receptor Against CD38 in B-Cell Malignancies.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 2356-2356
Author(s):  
Keichiro Mihara ◽  
Kazuyoshi Yanagihara ◽  
Misato Takigahira ◽  
Takahiro Ochiya ◽  
Chihaya Imai ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cell ◽  
Jurkat Cells ◽  
Steady Increase ◽  
Dependent Manner ◽  
Chimeric Receptor ◽  
Activated T Cells ◽  
Peripheral T Cells

Abstract CD38 is expected to be one of the most useful molecular targets on the surface of malignant B-cells. T cell-mediated immunotherapy with a chimeric receptor could provide a powerful tool for treating cancer. However, since CD38 is also expressed on effector cells such as activated T cells, NK cells, and monocytes, these cells with the chimeric receptor could be eliminated by autologous cytotoxicity through the interaction with the antigen. In this study, we developed a novel methodology for enhancing the survival and clonal expansion of T lymphocytes expressing an anti-CD38 chimeric receptor. Hut78 T cells, which express very little CD38, retrovirally transduced with the anti-CD38 chimeric receptor showed powerful cytotoxic activity against B cell lines expressing CD38, such as HT (lymphoma), RPMI8226 (myeloma), 380 (ALL-Ph1−) and OP-1 (ALL-Ph1+) cells (mean specific cytotoxicity was 97.94% ± 0.31% after four days of culture in vitro). However, in activated human T cells and Jurkat cells constitutively expressing CD38, the recovery rate of cells transduced with the chimeric receptor was extremely low, because the cells eradicated each other and/or themselves by inducing apoptosis. To block the interaction of the anti-CD38 chimeric receptor with CD38 antigen, we incubated activated T cells and Jurkat cells in medium supplemented with an anti-CD38 antibody before the transduction. The number of viable cells harvested after the transduction was dramatically increased by the antibody in a dose-dependent manner. Using this method, we prepared human peripheral T cells bearing the chimeric receptor and injected them into NOD/SCID mice, which were transplanted with HT cells labeled with luciferase. Lucuferase activity was not detectable in 13 days in five of six mice with T cells transduced with the chimeric receptor. In contrast, the activity had a rapid and steady increase in all of the mice injected with vector-transduced T cells. These results clearly showed that even though human peripheral T cells express any molecule on their surface, an antibody could protect T cells transduced with a chimeric receptor-containing vector from cytolysis, and apoptosis. These findings may provide us with a powerful tool for improving T cell-mediated targeting therapy.

scholarly journals Venetoclax enhances T cell-mediated anti-leukemic activity by increasing ROS production

Blood ◽  
2021 ◽  
Author(s):  
JongBok Lee ◽  
Dilshad H. Khan ◽  
Rose Hurren ◽  
Mingjing Xu ◽  
Yoosu Na ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Mechanism Of Action ◽  
Adoptive Cell Therapy ◽  
Complete Response ◽  
Ros Generation ◽  
Activated T Cells ◽  
Treatment Naïve

Venetoclax, a Bcl-2 inhibitor, in combination with the hypomethylating agent, Azacytidine, achieves complete response with or without count recovery in approximately 70% of treatment-naïve elderly patients unfit for conventional intensive chemotherapy. However, the mechanism of action of this drug combination is not fully understood. We discovered that Venetoclax directly activated T cells to increase their cytotoxicity against AML in vitro and in vivo. Venetoclax enhanced T cell effector function by increasing ROS generation through inhibition of respiratory chain supercomplexes formation. In addition, Azacytidine induced a viral-mimicry response in AML cells by activating the STING/cGAS pathway, thereby rendering the AML cells more susceptible to T-cell mediated cytotoxicity. Similar findings were seen in patients treated with Venetoclax as this treatment increased ROS generation and activated T cells. Collectively, this study demonstrates a new immune mediated mechanism of action for Venetoclax and Azacytidine in the treatment of AML and highlights a potential combination of Venetoclax and adoptive cell therapy for patients with AML.

scholarly journals The Activated Type 1–Polarized Cd8+ T Cell Population Isolated from an Effector Site Contains Cells with Flexible Cytokine Profiles

1999 ◽  
Vol 190 (8) ◽  
pp. 1081-1092 ◽  
Author(s):  
Anthony G. Doyle ◽  
Kathy Buttigieg ◽  
Penny Groves ◽  
Barbara J. Johnson ◽  
Anne Kelso
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Population ◽  
Expression Profiles ◽  
Lung Parenchyma ◽  
Activated T Cells ◽  
Cytokine Genes ◽  
Effector Site

The capacity of activated T cells to alter their cytokine expression profiles after migration into an effector site has not previously been defined. We addressed this issue by paired daughter analysis of a type 1–polarized CD8+ effector T cell population freshly isolated from lung parenchyma of influenza virus–infected mice. Single T cells were activated to divide in vitro; individual daughter cells were then micromanipulated into secondary cultures with and without added IL-4 to assess their potential to express type 2 cytokine genes. The resultant subclones were analyzed for type 1 and 2 cytokine mRNAs at day 6–7. When the most activated (CD44highCD11ahigh) CD8+ subpopulation from infected lung was compared with naive or resting (CD44lowCD11alow) CD8+ cells from infected lung and from normal lymph nodes (LNs), both clonogenicity and plasticity of the cytokine response were highest in the LN population and lowest in the activated lung population, correlating inversely with effector function. Multipotential cells were nevertheless detected among clonogenic CD44highCD11ahigh lung cells at 30–50% of the frequency in normal LNs. The data indicate that activated CD8+ T cells can retain the ability to proliferate and express new cytokine genes in response to local stimuli after recruitment to an effector site.

T cell-T cell activation in multiple sclerosis

1997 ◽  
Vol 3 (4) ◽  
pp. 238-242 ◽  
Author(s):  
JW Lindsey ◽  
RH Kerman ◽  
JS Wolinsky
Keyword(s):  
Multiple Sclerosis ◽  
T Cells ◽  
T Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Viral Infections ◽  
Activated T Cells ◽  
In Vitro Proliferation

Activated T cells are able to stimulate proliferation in resting T cells through an antigen non-specific mechanism. The in vivo usefulness of this T cell-T cell activation is unclear, but it may serve to amplify immune responses. T cell-T cell activation could be involved in the well-documented occurrence of multiple sclerosis (MS) exacerbations following viral infections. Excessive activation via this pathway could also be a factor in the etiology of MS. We tested the hypothesis that excessive T cell-T cell activation occurs in MS patients using in vitro proliferation assays comparing T cells from MS patients to T cells from controls. When tested as responder cells, T cells from MS patients proliferated slightly less after stimulation with previously activated cells than T cells from controls. When tested as stimulator cells, activated cells from MS patients stimulated slightly more non-specific proliferation than activated cells from controls. Neither of these differences were statistically significant We conclude that T cell proliferation in response to activated T cells is similar in MS and controls.

scholarly journals TCR+CD4−CD8− (double negative) T cells protect from cisplatin-induced renal epithelial cell apoptosis and acute kidney injury

2020 ◽  
Vol 318 (6) ◽  
pp. F1500-F1512
Author(s):  
Jing Gong ◽  
Sanjeev Noel ◽  
Joshua Hsu ◽  
Errol L. Bush ◽  
Lois J. Arend ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Epithelial Cells ◽  
Kidney Injury ◽  
Double Negative ◽  
Tubular Epithelial Cells ◽  
Proximal Tubular Epithelial Cells ◽  
Proximal Tubular ◽  
Induced Apoptosis

Acute kidney injury (AKI) due to cisplatin is a significant problem that limits its use as an effective chemotherapeutic agent. T cell receptor+CD4−CD8− double negative (DN) T cells constitute the major T cell population in the human and mouse kidney, express programmed cell death protein (PD)-1, and protect from ischemic AKI. However, the pathophysiological roles of DN T cells in cisplatin-induced AKI is unknown. In this study, wild-type mice were treated with cisplatin (30 mg/kg) or vehicle, and the effects on kidney DN T cell numbers and function were measured. In vitro experiments evaluated effects of kidney DN T cells on cisplatin-induced apoptosis and PD ligand 1 (PD-L1) in renal epithelial cells. Adoptive transfer experiments assessed the therapeutic potential of DN T cells during cisplatin-induced AKI. Our results show that kidney DN T cell population increased at 24 h and declined by 72 h after cisplatin treatment. Cisplatin treatment increased kidney DN T cell proliferation, apoptosis, CD69, and IL-10 expression, whereas CD62L, CD44, IL-17A, interferon-γ, and TNF-α were downregulated. Cisplatin treatment decreased both PD-1 and natural killer 1.1 subsets of kidney DN T cells with a pronounced effect on the PD-1 subset. In vitro kidney DN T cell coculture decreased cisplatin-induced apoptosis in kidney proximal tubular epithelial cells, increased Bcl-2, and decreased cleaved caspase 3 expression. Cisplatin-induced expression of PD ligand 1 was reduced in proximal tubular epithelial cells cocultured with DN T cells. Adoptive transfer of DN T cells attenuated kidney dysfunction and structural damage from cisplatin-induced AKI. These results demonstrate that kidney DN T cells respond rapidly and play a protective role during cisplatin-induced AKI.

scholarly journals Production and characterization of a bispecific IgG capable of inducing T-cell-mediated lysis of malignant B cells

Blood ◽  
1993 ◽  
Vol 81 (12) ◽  
pp. 3343-3349 ◽  
Author(s):  
BK Link ◽  
GJ Weiner
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
B Cell ◽  
Hybridoma Cells ◽  
Activated T Cells ◽  
Human B Cells ◽  
B Cell Malignancy ◽  
Cell Malignancy

Abstract Bispecific monoclonal antibodies (bsabs) recognizing both CD3 and a tumor antigen can redirect T-cell-mediated cytotoxicity toward cells bearing that antigen. Such bsabs have been shown to be more effective than monospecific monoclonal antibodies (MoAbs) at preventing tumor growth in animal models of B-cell malignancy. The current studies describe the production and preliminary evaluation of a bsab designed to induce the lysis of malignant human B cells by human T cells. The bsab was obtained from a hybrid-hybridoma cell line produced by fusing OKT3-secreting hybridoma cells with hybridoma cells that secrete 1D10. 1D10 is an MoAb that recognizes an antigen found on a majority of malignant human B cells that has not been detected to a significant degree on normal resting or activated lymphocytes. High performance liquid chromatography (HPLC) was used to separate bsab from monospecific antibodies that were also present in the hybrid-hybridoma antibody product. The bsab was then evaluated in vitro for its ability to induce lysis of malignant B cells by activated T cells. The bsab consistently induced extensive lysis in vitro of 1D10 (+) cells, including both cell lines and cells obtained from patients with a variety of B-cell malignancies. No such effect was seen with activated T cells alone or activated T cells with monospecific antibody. No increased lysis was seen with 1D10 (-) cell lines. The bsab also mediated lysis of malignant B cells by autologous T cells. We conclude bsab containing an OKT3 arm and a 1D10 arm can induce T-cell-mediated lysis in a manner that is both potent and specific. This supports further evaluation of this bsab as a potential immunotherapy of B-cell malignancy.

scholarly journals SBF-1 inhibits contact hypersensitivity in mice through down-regulation of T-cell-mediated responses

2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Wei Chen ◽  
Xianying Fang ◽  
Yuan Gao ◽  
Ke Shi ◽  
Lijun Sun ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Lymphocytes ◽  
Contact Hypersensitivity ◽  
Immunosuppressive Activity ◽  
Con A ◽  
Activated T Cells ◽  
Picryl Chloride

Abstract Background T lymphocytes play an important role in contact hypersensitivity. This study aims to explore the immunosuppressive activity of SBF-1, an analog of saponin OSW-1, against T lymphocytes in vitro and in vivo. Methods Proliferation of T lymphocytes from lymph nodes of mice was determined by MTT assay. Flow cytometry analysis was performed to assess T cell activation and apoptosis. Levels of cytokines were determined by PCR and ELISA. BALB/c mice were sensitized and challenged with picryl chloride and thickness of left and right ears were measured. Results SBF-1 effectively inhibited T lymphocytes proliferation induced by concanavalin A (Con A) or anti-CD3 plus anti-CD28 at a very low dose (10 nM) but exhibited little toxicity in non-activated T lymphocytes at concentrations up to 10 μM. In addition, SBF-1 inhibited the expression of CD25 and CD69, as well as he phosphorylation of AKT in Con A-activated T cells. SBF-1 also induced apoptosis of activated T cells. In addition, SBF-1 also downregulated the induction of the T cell cytokines, IL-2 and IFN-γ in a dose-dependent manner. Furthermore, SBF-1 significantly suppressed ear swelling and inflammation in a mouse model of picryl chloride-induced contact hypersensitivity. Conclusions Our findings suggest that SBF-1 has an unique immunosuppressive activity both in vitro and in vivo mainly through inhibiting T cell proliferation and activation. Its mechanism appears to be related to the blockage of AKT signaling pathway.

scholarly journals Clinical and in vitro resistance to bexarotene in adult T-cell leukemia: loss of RXR-α receptor

Blood ◽  
2008 ◽  
Vol 112 (6) ◽  
pp. 2484-2488 ◽  
Author(s):  
Julie H. Lin ◽  
Ellen J. Kim ◽  
Anand Bansal ◽  
John Seykora ◽  
Stephen K. Richardson ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Peripheral Blood ◽  
T Cell Leukemia ◽  
Cell Leukemia ◽  
Adult T Cell Leukemia ◽  
First Case ◽  
Induced Apoptosis ◽  
Resistant Cells

Abstract The oral rexinoid bexarotene (Targretin) is widely used for treatment of cutaneous T-cell lymphomas (CTCL). We recently reported the first case of adult T-cell leukemia/lymphoma (ATLL) that responded rapidly to combination therapy of bexarotene and interferon (IFN)-α2b with complete clinical response. We demonstrated that bexarotene induced apoptosis of the patient's malignant peripheral blood T-cells in vitro. However, our patient developed skin and nodal relapse 180 days after starting treatment. We now demonstrate that his peripheral blood malignant T cells became resistant to bexarotene-induced apoptosis. We investigated potential mechanisms that may cause aberrations in the retinoid X receptor (RXR) subunits, RXR-α and RXR-β, to account for these findings. Sequence analysis did not reveal acquisition of mutations in the genes encoding RXR-α and RXR-β by resistant cells. We assessed RXR-α and RXR-β expression by Western blot analysis and found that resistant cells had significantly decreased RXR-α expression compared with pretherapy bexarotene-sensitive cells. Our findings indicate that reduced expression of the RXR-α receptor subunit may represent a mechanism for resistance to bexarotene in T-cell malignancies.

scholarly journals A subclass of dendritic cells kills CD4 T cells via Fas/Fas-ligand-induced apoptosis.

1996 ◽  
Vol 183 (4) ◽  
pp. 1789-1796 ◽  
Author(s):  
G Süss ◽  
K Shortman
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
Cd4 T Cells ◽  
Fas Ligand ◽  
Activated T Cells ◽  
T Cell Apoptosis ◽  
Peripheral T Cells ◽  
Surface Staining ◽  
Induced Apoptosis ◽  
Antigen Presenting

Dendritic cells (DC), the most efficient antigen-presenting cells, are well equipped for activation of naive CD4+ T cells by their expression of high levels of major histocompatibility complex and costimulator molecules. We now demonstrate that some DC are equally well equipped for killing these same T cells. Murine splenic DC consist of both conventional CD8alpha- DC and a major population of CD8alpha+ DC. Whereas CD8- DC induce a vigorous proliferative response in CD4 T cells, CD8+ DC induce a lesser response that is associated with marked T cell apoptosis. By using various mixtures of T cells and DC from Fas-mutant lpr/lpr mice and Fas-ligand (FasL) mutant gld/gld mice, we show this death is due to interaction of Fas on activated T cells with FasL on CD8+ DC. Furthermore, we show by direct surface staining that CD8+ DC, but not CD8- DC, express FasL at high levels. These findings indicate that FasL+ CD8+ DC are a specialized subgroup of DC with a role in the regulation of the response of primary peripheral T cells.

Adoptive Transfer of Adenovirus Specific T-Cells in Children with Systemic Adenovirus Infection after Allogeneic Stem Cell Transplantation.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 80-80
Author(s):  
Tobias F. Feuchtinger ◽  
Susanne Matthes-Martin ◽  
Celine Richard ◽  
Thomas Lion ◽  
Klaus Hamprecht ◽  
...  
Keyword(s):  
T Cells ◽  
Stem Cell ◽  
T Cell ◽  
Stem Cell Transplantation ◽  
Adoptive Transfer ◽  
Cell Transfer ◽  
New Treatment ◽  
T Cell Transfer

Abstract Allogeneic stem cell transplantation (SCT) has become an increasing treatment option for a variety of malignant and non-malignant disease. During immune reconstitution the host is at significant risk for viral infections. Human adenovirus (HAdV) infection is especially in children an important and serious complication. Virus-specific T-cells are essential for the clearance of HAdV, since antiviral chemotherapy has been insufficient to date. We present a new treatment option using virus-specific donor T-cells for adoptive transfer of immunity to patients with systemic HAdV-infection. We isolated in 6 patients with systemic HAdV-infection after SCT virus-specific T-cells of the donor, according to INF-γ secretion after short in vitro stimulation with viral antigen, resulting in a combination of CD4+ and CD8+ T-cells. Between 5-50x103/kg T-cells were infused for adoptive transfer. For follow-up, the infection and the in-vivo expansion of infused T-cells were evaluated. Isolated cells showed high specificity and markedly reduced but residual alloreactivity in-vitro. In three of four evaluable patients the infused T-cells underwent an in-vivo expansion and in these three patients the viral load decreased in peripheral blood after adoptive T-cell transfer. In-vivo expansion of specific T-cells was dose-independent. T-cell infusion was well tolerated. One patient experienced GvHD°II of the skin after T-cell transfer. In conclusion specific T-cell immunotherapy as a new treatment approach for children was performed in 6 cases of systemic HAdV-infection after allogeneic SCT. Induction of a specific T-cell response through adoptive transfer has been shown feasible and effective to protect from HAdV-related complications.

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