scholarly journals Cell-intrinsic activation of Orai1 regulates human T cell motility

2017 ◽  
Author(s):  
Tobias X. Dong ◽  
Milton L. Greenberg ◽  
Sabrina Leverrier ◽  
Ying Yu ◽  
Ian Parker ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Lymph Nodes ◽  
Cell Motility ◽  
Cell Function ◽  
Immune Surveillance ◽  
Dominant Negative ◽  
Human T Cell ◽  
A Cell

AbstractCa2+ signaling through the store-operated Ca2+ channel, Orai1, is crucial for T cell function, but a role in regulating T cell motility in lymph nodes has not been previously reported. Tracking human T cells in immunodeficient mouse lymph nodes and in microfabricated PDMS channels, we show that inhibition of Orai1 channel activity with a dominant-negative Orai1-E106A construct increases average T cell velocities by reducing the frequency of pauses in motile T cells. Orai1-dependent motility arrest occurs spontaneously during confined motility in vitro, even in the absence of extrinsic cell contacts or antigen recognition. Utilizing a novel ratiometric genetically encoded cytosolic Ca2+ indicator, Salsa6f, we show these spontaneous pauses during T cell motility in vitro coincide with episodes of spontaneous cytosolic Ca2+ signaling. Our results demonstrate that Orai1, activated in a cell-intrinsic manner, regulates T cell motility patterns that accompany immune surveillance.

scholarly journals Intermittent Ca2+ signals mediated by Orai1 regulate basal T cell motility

2017 ◽  
Author(s):  
Tobias X. Dong ◽  
Shivashankar Othy ◽  
Milton L. Greenberg ◽  
Amit Jairaman ◽  
Chijioke Akunwafo ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Motility ◽  
Immune Surveillance ◽  
Cellular Motility ◽  
Average Cell ◽  
Cell Functions ◽  
Human T Cells

AbstractCa2+ influx through Orai1 channels is crucial for several T cell functions, but a role in regulating basal cellular motility has not been described. Here we show that inhibition of Orai1 channel activity increases average cell velocities by reducing the frequency of pauses in human T cells migrating through confined spaces, even in the absence of extrinsic cell contacts or antigen recognition. Utilizing a novel ratiometric genetically encoded cytosolic Ca2+ indicator, Salsa6f, which permits real-time monitoring of cytosolic Ca2+ along with cell motility, we show that spontaneous pauses during T cell motility in vitro and in vivo coincide with episodes of cytosolic Ca2+ signaling. Furthermore, lymph node T cells exhibited two types of spontaneous Ca2+ transients: short-duration “sparkles” and longer duration global signals. Our results demonstrate that spontaneous and self-peptide MHC-dependent activation of Orai1 ensures random walk behavior in T cells to optimize immune surveillance.

scholarly journals A multivariate, quantitative assay that disentangles key kinetic parameters of primary human T cell function in vitro

PLoS ONE ◽  
2020 ◽  
Vol 15 (11) ◽  
pp. e0241421
Author(s):  
Grace L. Huang ◽  
Daniel P. Nampe ◽  
Jason Yi ◽  
Grant B. Gabrelow ◽  
Kathleen R. Negri ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Function ◽  
Limiting Factor ◽  
Preclinical Development ◽  
Effector Cells ◽  
Recent Success ◽  
Natural Ligand ◽  
Human T Cell

Cell therapy is poised to play a larger role in medicine, most notably for immuno-oncology. Despite the recent success of CAR-T therapeutics in the treatment of blood tumors and the rapid progress toward improved versions of both CAR- and TCR-Ts, important analytical aspects of preclinical development and manufacturing of engineered T cells remain immature. One limiting factor is the absence of robust multivariate assays to disentangle key parameters related to function of engineered effector cells, especially in the peptide-MHC (pMHC) target realm, the natural ligand for TCRs. Here we describe an imaging-based primary T cell assay that addresses several of these limitations. To our knowledge, this assay is the first quantitative, high-content assay that separates the key functional parameters of time- and antigen-dependent T cell proliferation from cytotoxicity. We show that the assay sheds light on relevant biology of CAR- and TCR-T cells, including response kinetics and the influence of effector:target ratio.

scholarly journals Intermittent Ca2+ signals mediated by Orai1 regulate basal T cell motility

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Tobias X Dong ◽  
Shivashankar Othy ◽  
Milton L Greenberg ◽  
Amit Jairaman ◽  
Chijioke Akunwafo ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Motility ◽  
Immune Surveillance ◽  
Cellular Motility ◽  
Average Cell ◽  
Cell Functions ◽  
Human T Cells

Ca2+ influx through Orai1 channels is crucial for several T cell functions, but a role in regulating basal cellular motility has not been described. Here, we show that inhibition of Orai1 channel activity increases average cell velocities by reducing the frequency of pauses in human T cells migrating through confined spaces, even in the absence of extrinsic cell contacts or antigen recognition. Utilizing a novel ratiometric genetically encoded cytosolic Ca2+ indicator, Salsa6f, which permits real-time monitoring of cytosolic Ca2+ along with cell motility, we show that spontaneous pauses during T cell motility in vitro and in vivo coincide with episodes of cytosolic Ca2+ signaling. Furthermore, lymph node T cells exhibited two types of spontaneous Ca2+ transients: short-duration ‘sparkles’ and longer duration global signals. Our results demonstrate that spontaneous and self-peptide MHC-dependent activation of Orai1 ensures random walk behavior in T cells to optimize immune surveillance.

scholarly journals Differential T Cell Function and Fate in Lymph Node and Nonlymphoid Tissues

2002 ◽  
Vol 195 (3) ◽  
pp. 317-326 ◽  
Author(s):  
Nicola L. Harris ◽  
Victoria Watt ◽  
Franca Ronchese ◽  
Graham Le Gros
Keyword(s):  
T Cells ◽  
Lymph Node ◽  
T Cell ◽  
Lymph Nodes ◽  
Cell Function ◽  
Activated T Cells ◽  
Peripheral Tissues ◽  
Cell Immunity ◽  
Effector Cytokines

The functions and fate of antigen-experienced T cells isolated from lymph node or nonlymphoid tissues were analyzed in a system involving adoptive transfer of in vitro–activated T cells into mice. Activated T cells present in the lymph nodes could be stimulated by antigen to divide, produce effector cytokines, and migrate to peripheral tissues. By contrast, activated T cells that had migrated into nonlymphoid tissues (lung and airway) produced substantial effector cytokines upon antigen challenge, but were completely unable to divide or migrate back to the lymph nodes. Therefore, activated T cells can undergo clonal expansion in the lymph node, but are recruited and retained as nondividing cells in nonlymphoid tissues. These distinct regulatory events in lymph node and nonlymphoid tissues reveal simple key mechanisms for both inducing and limiting T cell immunity.

scholarly journals DL4-μbeads induce T cell lineage differentiation from stem cells in a stromal cell-free system

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Ashton C. Trotman-Grant ◽  
Mahmood Mohtashami ◽  
Joshua De Sousa Casal ◽  
Elisa C. Martinez ◽  
Dylan Lee ◽  
...  
Keyword(s):  
Stem Cells ◽  
T Cells ◽  
T Cell ◽  
Stromal Cell ◽  
Hematopoietic Stem ◽  
Free System ◽  
Cell Therapies ◽  
Immunodeficient Mice ◽  
Human T Cell

AbstractT cells are pivotal effectors of the immune system and can be harnessed as therapeutics for regenerative medicine and cancer immunotherapy. An unmet challenge in the field is the development of a clinically relevant system that is readily scalable to generate large numbers of T-lineage cells from hematopoietic stem/progenitor cells (HSPCs). Here, we report a stromal cell-free, microbead-based approach that supports the efficient in vitro development of both human progenitor T (proT) cells and T-lineage cells from CD34+cells sourced from cord blood, GCSF-mobilized peripheral blood, and pluripotent stem cells (PSCs). DL4-μbeads, along with lymphopoietic cytokines, induce an ordered sequence of differentiation from CD34+ cells to CD34+CD7+CD5+ proT cells to CD3+αβ T cells. Single-cell RNA sequencing of human PSC-derived proT cells reveals a transcriptional profile similar to the earliest thymocytes found in the embryonic and fetal thymus. Furthermore, the adoptive transfer of CD34+CD7+ proT cells into immunodeficient mice demonstrates efficient thymic engraftment and functional maturation of peripheral T cells. DL4-μbeads provide a simple and robust platform to both study human T cell development and facilitate the development of engineered T cell therapies from renewable sources.

Wogonin preferentially kills malignant lymphocytes and suppresses T-cell tumor growth by inducing PLCγ1- and Ca2+-dependent apoptosis

Blood ◽  
2008 ◽  
Vol 111 (4) ◽  
pp. 2354-2363 ◽  
Author(s):  
Sven Baumann ◽  
Stefanie C. Fas ◽  
Marco Giaisi ◽  
Wolfgang W. Müller ◽  
Anette Merling ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Chinese Medicine ◽  
Traditional Chinese Medicine ◽  
Therapeutic Potential ◽  
Human T Cell ◽  
Voltage Dependent ◽  
Ca2 Channels ◽  
Malignant T Cells

Herbs have successfully been used in traditional Chinese medicine for centuries. However, their curative mechanisms remain largely unknown. In this study, we show that Wogonin, derived from the traditional Chinese medicine Huang-Qin (Scutellaria baicalensis Georgi), induces apoptosis in malignant T cells in vitro and suppresses growth of human T-cell leukemia xenografts in vivo. Importantly, Wogonin shows almost no toxicity on T lymphocytes from healthy donors. Wogonin induces prolonged activation of PLCγ1 via H2O2 signaling in malignant T cells, which leads to sustained elevation of cytosolic Ca2+ in malignant but not normal T cells. Subsequently, a Ca2+ overload leads to disruption of the mitochondrial membrane. The selective effect of Wogonin is due to its differential regulation of the redox status of malignant versus normal T cells. In addition, we show that the L-type voltage-dependent Ca2+ channels are involved in the intracellular Ca2+ mobilization in T cells. Furthermore, we show that malignant T cells possess elevated amounts of voltage-dependent Ca2+ channels compared with normal T cells, which further enhance the cytotoxicity of Wogonin for malignant T cells. Taken together, our data show a therapeutic potential of Wogonin for the treatment of hematologic malignancies.

109 Dominant-negative TGFβ receptor 2 enhances GPC3-targeting CAR-T cell efficacy against hepatocellular carcinoma

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A121-A121
Author(s):  
Nina Chu ◽  
Michael Overstreet ◽  
Ryan Gilbreth ◽  
Lori Clarke ◽  
Christina Gesse ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Flow Cytometry ◽  
T Cells ◽  
T Cell ◽  
Dominant Negative ◽  
Car T Cells ◽  
Car T Cell ◽  
Car T

BackgroundChimeric antigen receptors (CARs) are engineered synthetic receptors that reprogram T cell specificity and function against a given antigen. Autologous CAR-T cell therapy has demonstrated potent efficacy against various hematological malignancies, but has yielded limited success against solid cancers. MEDI7028 is a CAR that targets oncofetal antigen glypican-3 (GPC3), which is expressed in 70–90% of hepatocellular carcinoma (HCC), but not in normal liver tissue. Transforming growth factor β (TGFβ) secretion is increased in advanced HCC, which creates an immunosuppressive milieu and facilitates cancer progression and poor prognosis. We tested whether the anti-tumor efficacy of a GPC3 CAR-T can be enhanced with the co-expression of dominant-negative TGFβRII (TGFβRIIDN).MethodsPrimary human T cells were lentivirally transduced to express GPC3 CAR both with and without TGFβRIIDN. Western blot and flow cytometry were performed on purified CAR-T cells to assess modulation of pathways and immune phenotypes driven by TGFβ in vitro. A xenograft model of human HCC cell line overexpressing TGFβ in immunodeficient mice was used to investigate the in vivo efficacy of TGFβRIIDN armored and unarmored CAR-T. Tumor infiltrating lymphocyte populations were analyzed by flow cytometry while serum cytokine levels were quantified with ELISA.ResultsArmoring GPC3 CAR-T with TGFβRIIDN nearly abolished phospho-SMAD2/3 expression upon exposure to recombinant human TGFβ in vitro, indicating that the TGFβ signaling axis was successfully blocked by expression of the dominant-negative receptor. Additionally, expression of TGFβRIIDN suppressed TGFβ-driven CD103 upregulation, further demonstrating attenuation of the pathway by this armoring strategy. In vivo, the TGFβRIIDN armored CAR-T achieved superior tumor regression and delayed tumor regrowth compared to the unarmored CAR-T. The armored CAR-T cells infiltrated HCC tumors more abundantly than their unarmored counterparts, and were phenotypically less exhausted and less differentiated. In line with these observations, we detected significantly more interferon gamma (IFNγ) at peak response and decreased alpha-fetoprotein in the serum of mice treated with armored cells compared to mice receiving unarmored CAR-T, demonstrating in vivo functional superiority of TGFβRIIDN armored CAR-T therapy.ConclusionsArmoring GPC3 CAR-T with TGFβRIIDN abrogates the signaling of TGFβ in vitro and enhances the anti-tumor efficacy of GPC3 CAR-T against TGFβ-expressing HCC tumors in vivo, proving TGFβRIIDN to be an effective armoring strategy against TGFβ-expressing solid malignancies in preclinical models.Ethics ApprovalThe study was approved by AstraZeneca’s Ethics Board and Institutional Animal Care and Use Committee (IACUC).

scholarly journals TRPM2 Is Not Required for T-Cell Activation and Differentiation

2022 ◽  
Vol 12 ◽  
Author(s):  
Niels C. Lory ◽  
Mikolaj Nawrocki ◽  
Martina Corazza ◽  
Joanna Schmid ◽  
Valéa Schumacher ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Transient Receptor Potential ◽  
Cell Function ◽  
Intestinal Inflammation ◽  
Activation Markers

Antigen recognition by the T-cell receptor induces a cytosolic Ca2+ signal that is crucial for T-cell function. The Ca2+ channel TRPM2 (transient receptor potential cation channel subfamily M member 2) has been shown to facilitate influx of extracellular Ca2+ through the plasma membrane of T cells. Therefore, it was suggested that TRPM2 is involved in T-cell activation and differentiation. However, these results are largely derived from in vitro studies using T-cell lines and non-physiologic means of TRPM2 activation. Thus, the relevance of TRPM2-mediated Ca2+ signaling in T cells remains unclear. Here, we use TRPM2-deficient mice to investigate the function of TRPM2 in T-cell activation and differentiation. In response to TCR stimulation in vitro, Trpm2-/- and WT CD4+ and CD8+ T cells similarly upregulated the early activation markers NUR77, IRF4, and CD69. We also observed regular proliferation of Trpm2-/- CD8+ T cells and unimpaired differentiation of CD4+ T cells into Th1, Th17, and Treg cells under specific polarizing conditions. In vivo, Trpm2-/- and WT CD8+ T cells showed equal specific responses to Listeria monocytogenes after infection of WT and Trpm2-/- mice and after transfer of WT and Trpm2-/- CD8+ T cells into infected recipients. CD4+ T-cell responses were investigated in the model of anti-CD3 mAb-induced intestinal inflammation, which allows analysis of Th1, Th17, Treg, and Tr1-cell differentiation. Here again, we detected similar responses of WT and Trpm2-/- CD4+ T cells. In conclusion, our results argue against a major function of TRPM2 in T-cell activation and differentiation.

scholarly journals Lipid Microbubble–Conjugated Anti-CD3 and Anti-CD28 Antibodies (Microbubble-Based Human T Cell Activator) Offer Superior Long-Term Expansion of Human Naive T Cells In Vitro

2020 ◽  
Vol 4 (8) ◽  
pp. 475-484
Author(s):  
Ana Lustig ◽  
Ty’Keemi Manor ◽  
Guixin Shi ◽  
Jiangyuan Li ◽  
Ying-Ting Wang ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Naive T Cells ◽  
Naïve T Cells ◽  
Human T Cell ◽  
Cell Activator

scholarly journals CD28-independent, TRAF2-dependent Costimulation of Resting T Cells by 4-1BB Ligand

1998 ◽  
Vol 187 (11) ◽  
pp. 1849-1862 ◽  
Author(s):  
Katina Saoulli ◽  
Soo Young Lee ◽  
Jennifer L. Cannons ◽  
Wen Chen Yeh ◽  
Angela Santana ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Expression System ◽  
Baculovirus Expression System ◽  
Dominant Negative ◽  
Soluble Form ◽  
Tnf Receptor

4-1BB ligand (4-1BBL) is a member of the tumor necrosis factor (TNF) family expressed on activated antigen-presenting cells. Its receptor, 4-1BB, is a member of the TNF receptor family expressed on activated CD4 and CD8 T cells. We have produced a soluble form of 4-1BBL using the baculovirus expression system. When coimmobilized on plastic with anti-CD3, soluble 4-1BBL induces interleukin (IL)-2 production by resting CD28+ or CD28− T cells, indicating that 4-1BBL can function independently of other cell surface molecules, including CD28, in costimulation of resting T cell activation. At low concentrations of anti-CD3, 4-1BBL is inferior to anti-CD28 in T cell activation. However, when 4-1BB ligand is provided together with strong TCR signals, then 4-1BBL and anti-CD28 are equally potent in stimulation of IL-2 production by resting T cells. We find that TNF receptor–associated factor (TRAF)1 or TRAF2 associate with a glutathione S-transferase–4-1BB cytoplasmic domain fusion protein in vitro. In T cells, we find that association of TRAF1 and TRAF2 with 4-1BB requires 4-1BB cross-linking. In support of a functional role for TRAF2 in 4-1BB signaling, we find that resting T cells isolated from TRAF2-deficient mice or from mice expressing a dominant negative form of TRAF2 fail to augment IL-2 production in response to soluble 4-1BBL. Thus 4-1BB, via the TRAF2 molecule, can provide CD28-independent costimulatory signals to resting T cells.

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