Human T Cell Activation by Costimulatory Signal-Deficient Allogeneic Cells Induces Inducible Costimulator-Expressing Anergic T Cells with Regulatory Cell Activity

AbstractThe factors and signals driving T cell activation and polarisation during immune responses have been studied mainly at the level of cells and chemical mediators. Here we describe a physical driver of these processes in the form of physiological-strength electric fields (EFs). EFs are generated at sites where epithelium is disrupted (e.g. wounded skin/bronchial epithelia) and where T cells frequently are present. Using live-cell imaging, we show human primary T cells migrate directionally to the cathode in low strength (50/150 mV/mm) EFs. Strikingly, we show for the first time that EFs significantly downregulate T cell activation following stimulation with antigen-activated APCs or anti-CD3/CD28 antibodies, as demonstrated by decreased IL-2 secretion and proliferation. These EF-induced functional changes were accompanied by a significant dampening of CD4+ T cell polarisation. Expression of critical markers of the Th17 lineage, RORγt and IL-17, and the Th17 polarisation mediator phospho-STAT3 were reduced significantly, while STAT1, ERK and c-Jun phosphorylation were comparatively unaffected suggesting STAT3 modulation by EFs as one mechanism driving effects. Overall, we identify electrical signals as important contributors to the co-ordination and regulation of human T cell functions, paving the way for a new research area into effects of naturally occurring and clinically-applied EFs in conditions where control of T cell activity is paramount.

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P07.02 Regulation of CD19 CAR T- cell activation based on engineered Nuclear factor of activated T cells artificial transcription factors

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2021-itoc8.43 ◽

2021 ◽

Vol 9 (Suppl 1) ◽

pp. A23-A23

Author(s):

D Lainš&ccaron;ek ◽

V Mikoli&ccaron; ◽

Š Malenšek ◽

A Verbi&ccaron; ◽

R Jerala

Keyword(s):

T Cells ◽

T Cell ◽

T Cell Activation ◽

Cell Activation ◽

Cell Activity ◽

External Control ◽

Car T Cells ◽

Car T Cell ◽

Artificial Transcription Factors ◽

Car T

BackgroundCD19 CAR T- cells (Chimeric antigen receptor T cells that recognize CD19) present a therapeutic option for various malignant diseases based on their ability to specifically recognize the selected tumour surface markers, triggering immune cell activation and cytokine production that results in killing cancerous cell expressing specific surface markers recognized by the CAR. The main therapeutic effect of CAR is a specific T cell activation of adequate cell number with sequential destruction of tumorous cells in a safe therapeutic manner. In order to increase T cell activation, different activation domains were introduced into CAR. CAR T-cells are highly efficient in tumour cell destruction, but may cause serious side effects that can also result in patient death so their activity needs to be carefully controlled.1 Several attempts were made to influence the CAR T cell proliferation and their activation by adding T cell growth factors, such as IL-2, into patients, however this approach of increasing the number of activating T cells with no external control over their number can again lead to non-optimal therapeutic effects. Different improvements were made by designing synthetic receptors or small molecule-inducible systems etc., which influence regulated expansion and survival of CAR T cells.2Material and MethodsIn order to regulate CD19 CAR-T cell activity, different NFAT2 based artificial transcription factors were prepared. The full length NFAT2, one of the main players in T cell IL2 production, a key cytokine for T cell activation and proliferation was truncated by deletion of its own activation domain. Next, we joined via Gibson assembly tNFAT21-593 coding sequence with domains of different heterodimerization systems that interact upon adding the inductor of heterodimerization. The interaction counterparts were fused to a strong tripartite transcriptional activator domain VPR and/or strong repressor domain KRAB resulting in formation of an engineered NFAT artificial transcription (NFAT-TF) factors with external control. To determine the activity of NFAT-TF HEK293, Jurkat or human T cells were used.ResultsBased on luciferase assay, carried out on NFAT-TF transfected HEK293 cells we first established that upon adding the external inductor of heterodimerization, efficient gene regulation occurs, according to VPR or KRAB domain appropriate functions. Findings were then transferred to Jurkat cells that were electroporated with appropriate DNA constructs, coding for NFAT-TF and CD19 CAR. After Raji:Jurkat co-culture ELISA measurements revealed that IL2 production and therefore CD19 CAR-T cell activity can be controlled by the action of NFAT-TF. The same regulation over the activity and subsequent proliferation status was also observed in retrovirally transduced human T-cells.ConclusionWe developed a regulatory system for therapeutic effect of CD19 CAR-T cells, a unique mechanism to control T cell activation and proliferation based on the engineered NFAT2 artificial transcription factor.ReferencesBonifant CL, et al. Toxicity and management in CAR T-cell therapy. Mol Ther Oncolytics 2016;3:16011.Wu C-Y, et al. Remote control of therapeutic T cells through a small molecule-gated chimeric receptor. Science 2015;80:350.Disclosure InformationD. Lainš&ccaron;ek: None. V. Mikoli&ccaron;: None. Š. Malenšek: None. A. Verbi&ccaron;: None. R. Jerala: None.

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Single-cell transcriptomics of human T cells reveals tissue and activation signatures in health and disease

Nature Communications ◽

10.1038/s41467-019-12464-3 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 54

Author(s):

Peter A. Szabo ◽

Hanna Mendes Levitin ◽

Michelle Miron ◽

Mark E. Snyder ◽

Takashi Senda ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Single Cell ◽

T Cell Activation ◽

Cell Activation ◽

Interferon Response ◽

Functional Responses ◽

Multiple Tumor ◽

Human T Cell ◽

Human T Cells

Abstract Human T cells coordinate adaptive immunity in diverse anatomic compartments through production of cytokines and effector molecules, but it is unclear how tissue site influences T cell persistence and function. Here, we use single cell RNA-sequencing (scRNA-seq) to define the heterogeneity of human T cells isolated from lungs, lymph nodes, bone marrow and blood, and their functional responses following stimulation. Through analysis of >50,000 resting and activated T cells, we reveal tissue T cell signatures in mucosal and lymphoid sites, and lineage-specific activation states across all sites including distinct effector states for CD8+ T cells and an interferon-response state for CD4+ T cells. Comparing scRNA-seq profiles of tumor-associated T cells to our dataset reveals predominant activated CD8+ compared to CD4+ T cell states within multiple tumor types. Our results therefore establish a high dimensional reference map of human T cell activation in health for analyzing T cells in disease.

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Role of Phosphodiesterase 7 (PDE7) in T Cell Activity. Effects of Selective PDE7 Inhibitors and Dual PDE4/7 Inhibitors on T Cell Functions

International Journal of Molecular Sciences ◽

10.3390/ijms21176118 ◽

2020 ◽

Vol 21 (17) ◽

pp. 6118 ◽

Cited By ~ 1

Author(s):

Marianna Szczypka

Keyword(s):

T Cells ◽

T Cell ◽

T Cell Activation ◽

Cell Activation ◽

Splice Variants ◽

Cell Activity ◽

Cell Functions ◽

Simultaneous Inhibition ◽

And Function

Phosphodiesterase 7 (PDE7), a cAMP-specific PDE family, insensitive to rolipram, is present in many immune cells, including T lymphocytes. Two genes of PDE7 have been identified: PDE7A and PDE7B with three or four splice variants, respectively. Both PDE7A and PDE7B are expressed in T cells, and the predominant splice variant in these cells is PDE7A1. PDE7 is one of several PDE families that terminates biological functions of cAMP—a major regulating intracellular factor. However, the precise role of PDE7 in T cell activation and function is still ambiguous. Some authors reported its crucial role in T cell activation, while according to other studies PDE7 activity was not pivotal to T cells. Several studies showed that inhibition of PDE7 by its selective or dual PDE4/7 inhibitors suppresses T cell activity, and consequently T-mediated immune response. Taken together, it seems quite likely that simultaneous inhibition of PDE4 and PDE7 by dual PDE4/7 inhibitors or a combination of selective PDE4 and PDE7 remains the most interesting therapeutic target for the treatment of some immune-related disorders, such as autoimmune diseases, or selected respiratory diseases. An interesting direction of future studies could also be using a combination of selective PDE7 and PDE3 inhibitors.

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Human T cell activation. IV. T cell activation and proliferation via the early activation antigen EA 1.

Journal of Experimental Medicine ◽

10.1084/jem.169.3.677 ◽

1989 ◽

Vol 169 (3) ◽

pp. 677-689 ◽

Cited By ~ 43

Author(s):

S Nakamura ◽

S S Sung ◽

J M Bjorndahl ◽

S M Fu

Keyword(s):

T Cells ◽

T Cell ◽

T Cell Activation ◽

Cell Activation ◽

Mrna Levels ◽

Dependent Manner ◽

Early Activation ◽

Human T Cell ◽

Accessory Cells ◽

Activation Antigen

A new mAb G38 was generated against purified EA 1, an early activation antigen. In immunoprecipitation, it was reactive with the same complex precipitated by the initial anti-EA 1 mAb P8. mAb G38 augmented PMA-induced proliferation of PBMC. It was shown to be mitogenic for purified T cells in collaboration with PMA in a dose-dependent manner. This effect was independent of monocytes and other accessory cells. mAb G38 augmented PMA-induced IL-2-R expression. In conjunction with PMA, it induced IL-2 synthesis and secretion. Its effects on IL-2-R and IL-2 expression were documented at both protein and mRNA levels. Both anti-EA 1 mAbs did not induce Ca2+ influx by themselves in PMA-treated T cells. However, the addition of second anti-mouse Ig antibodies induced readily detectable increases in [Ca2+]i. Ca2+-mediated pathways may be utilized as the transduction signal mechanisms. mAb Leu-23 was shown to be reactive with EA 1. mAb Leu-23 was also mitogenic for T cells in the presence of PMA. These findings provide evidence for a functional role for EA 1 in T cell activation and proliferation.

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Both Maturation and Survival of Human Dendritic Cells are Impaired in the Presence of Anergic/Suppressor T Cells

Clinical and Developmental Immunology ◽

10.1080/10446670310001593505 ◽

2003 ◽

Vol 10 (1) ◽

pp. 61-65 ◽

Cited By ~ 1

Author(s):

L. Frasca ◽

C. Scottà ◽

G. Lombardi ◽

E. Piccolella

Keyword(s):

T Cells ◽

Dendritic Cells ◽

T Cell ◽

T Cell Activation ◽

Cell Activation ◽

Costimulatory Molecule ◽

T Cell Suppression ◽

Cell Suppression ◽

Anergic T Cells ◽

Human Dendritic Cells

T cell suppression is a well established phenomenon, but the mechanisms involved are still a matter of debate. Mouse anergic T cells were shown to suppress responder T cell activation by inhibiting the antigen presenting function of DC. In the present work we studied the effects of co-culturing human anergic CD4+T cells with autologous dendritic cells (DC) at different stages of maturation. Either DC maturation or survival, depending on whether immature or mature DC where used as APC, was impaired in the presence of anergic cells. Indeed, MHC and costimulatory molecule up-regulation was inhibited in immature DC, whereas apoptotic phenomena were favored in mature DC and consequently in responder T cells. Defective ligation of CD40 by CD40L (CD154) was responsible for CD95-mediated and spontaneous apoptosis of DC as well as for a failure of their maturation process. These findings indicate that lack of activation of CD40 on DC by CD40L-defective anergic cells might be the primary event involved in T cell suppression and support the role of CD40 signaling in regulating both activation and survival of DC.

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Novel HPV-E7 immune modulators to activate HPV-specific T cells to eliminate cervical cancer.

Journal of Clinical Oncology ◽

10.1200/jco.2020.38.15_suppl.e18027 ◽

2020 ◽

Vol 38 (15_suppl) ◽

pp. e18027-e18027

Author(s):

Lihua Shi ◽

Di Zhang ◽

Susan Tam ◽

Man-Cheong Fung

Keyword(s):

T Cells ◽

T Cell ◽

Tumor Growth ◽

Tumor Cells ◽

T Cell Activation ◽

Cd8 T Cells ◽

Cell Activation ◽

Cell Activity ◽

Epitope Peptide ◽

Hpv E7

e18027 Background: Human papilloma virus (HPV) infection can lead to several types of cancers in both men and women. HPV+ tumor cells constitutively express the HPV-E7 antigen which can act as an oncogene to promote tumor growth and malignant transformation. Here, we report the application of novel Tavo Immune Modulator (TIM) biologics molecules which are consisted of a pMHC complex with an epitope peptide derived from HPV-E7 and co-stimulatory modulators of T cell activity. The HPV-E7 TIM molecules can specifically recognize and activate HPV-E7-specific T cells for the elimination of HPV affected cells. Methods: HPV-E7 TIM molecules were engineered as fusion molecules with HLA-A*02:01 MHC complexed with an HPV-E7 (11-20) epitope peptide at the N-termini, and various T cell costimulatory modulators at the C-termini of IgG heavy and light chains. TIM molecules were expressed in Expi293 cells and purified by Protein A affinity chromatography. Specific binding of TIM with HPV-E7 specific T cells was confirmed by immunostaining and flow cytometry. The activation and expansion of antigen specific CD8+ T cells were elucidated in T cell activation and recall assays. Results: HPV-E7 TIM molecules with various T cell co-stimulator molecules were engineered to specifically recognize HPV-specific T cells. Activation of T cells was antigen-specific and depended on the presence of an engineered T cell modulatory component on the TIM framework. The effects of various costimulatory molecules in different combinations on T cell activation were explored and an optimal combination was identified which facilitated high potency antigen-specific T cell activation. Such molecular combinations could facilitate T cell expansion and activation in T cell recall assays. Efficacy of HPV-E7 TIM molecules by inhibiting tumor growth in a syngeneic tumor model is ongoing. Conclusions: This study demonstrates that HPV-E7 TIM molecules selectively recognize and activate HPV-specific CD8+ T cells in the presence of a combination of two T cell costimulatory factors. Such novel biologics provide distinctive approaches in the treatment of HPV-related cancers and warrant further investigation. Additional in vitro and in vivo studies are ongoing to demonstrate the utility in eliminating HPV-infected tumor cells. Full data will be presented at the meeting.

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PAG-Associated FynT Regulates Calcium Signaling and Promotes Anergy in T Lymphocytes

Molecular and Cellular Biology ◽

10.1128/mcb.01983-06 ◽

2007 ◽

Vol 27 (5) ◽

pp. 1960-1973 ◽

Cited By ~ 50

Author(s):

Dominique Davidson ◽

Burkhart Schraven ◽

André Veillette

Keyword(s):

T Cells ◽

T Cell ◽

Tyrosine Phosphorylation ◽

T Cell Activation ◽

Protein Tyrosine Kinase ◽

Cell Activation ◽

T Cell Anergy ◽

Cell Anergy ◽

Anergic T Cells ◽

Selective Enhancement

ABSTRACT Phosphoprotein associated with glycolipid-enriched membranes (PAG), also named Csk-binding protein (Cbp), is a transmembrane adaptor associated with lipid rafts. It is phosphorylated on multiple tyrosines located in the cytoplasmic domain. One tyrosine, tyrosine 314 (Y314) in the mouse, interacts with Csk, a protein tyrosine kinase that negatively regulates Src kinases. This interaction enables PAG to inhibit T-cell antigen receptor (TCR)-mediated T-cell activation. PAG also associates with the Src-related kinase FynT. Genetic studies indicated that FynT was required for PAG tyrosine phosphorylation and binding of PAG to Csk in T cells. Herein, we investigated the function and regulation of PAG-associated FynT. Our data showed that PAG was constitutively associated with FynT in unstimulated T cells and that this association was rapidly lost in response to TCR stimulation. Dissociation of the PAG-FynT complex preceded PAG dephosphorylation and PAG-Csk dissociation after TCR engagement. Interestingly, in anergic T cells, the association of PAG with FynT, but not Csk, was increased. Analyses of PAG mutants provided evidence that PAG interacted with FynT by way of tyrosines other than Y314. Enforced expression of a PAG variant interacting with FynT, but not Csk, caused a selective enhancement of TCR-triggered calcium fluxes in normal T cells. Furthermore, it promoted T-cell anergy. Both effects were absent in mice lacking FynT, implying that the effects were mediated by PAG-associated FynT. Hence, besides enabling PAG tyrosine phosphorylation and the PAG-Csk interaction, PAG-associated FynT can stimulate calcium signals and favor T-cell anergy. These data improve our comprehension of the function of PAG in T cells. They also further implicate FynT in T-cell anergy.

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In Vitro Monitoring of Human T Cell Responses to Skin Sensitizing Chemicals—A Systematic Review

Cells ◽

10.3390/cells11010083 ◽

2021 ◽

Vol 11 (1) ◽

pp. 83

Author(s):

Marina Aparicio-Soto ◽

Caterina Curato ◽

Franziska Riedel ◽

Hermann-Josef Thierse ◽

Andreas Luch ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

T Cell Activation ◽

Cell Activation ◽

Cross Reactivity ◽

T Cell Epitopes ◽

Cell Responses ◽

Human T Cell ◽

The Individual

Background: Chemical allergies are T cell-mediated diseases that often manifest in the skin as allergic contact dermatitis (ACD). To prevent ACD on a public health scale and avoid elicitation reactions at the individual patient level, predictive and diagnostic tests, respectively, are indispensable. Currently, there is no validated in vitro T cell assay available. The main bottlenecks concern the inefficient generation of T cell epitopes and the detection of rare antigen-specific T cells. Methods: Here, we systematically review original experimental research papers describing T cell activation to chemical skin sensitizers. We focus our search on studies published in the PubMed and Scopus databases on non-metallic allergens in the last 20 years. Results: We identified 37 papers, among them 32 (86%) describing antigen-specific human T cell activation to 31 different chemical allergens. The remaining studies measured the general effects of chemical allergens on T cell function (five studies, 14%). Most antigen-specific studies used peripheral blood mononuclear cells (PBMC) as antigen-presenting cells (APC, 75%) and interrogated the blood T cell pool (91%). Depending on the individual chemical properties, T cell epitopes were generated either by direct administration into the culture medium (72%), separate modification of autologous APC (29%) or by use of hapten-modified model proteins (13%). Read-outs were mainly based on proliferation (91%), often combined with cytokine secretion (53%). The analysis of T cell clones offers additional opportunities to elucidate the mechanisms of epitope formation and cross-reactivity (13%). The best researched allergen was p-phenylenediamine (PPD, 12 studies, 38%). For this and some other allergens, stronger immune responses were observed in some allergic patients (15/31 chemicals, 48%), illustrating the in vivo relevance of the identified T cells while detection limits remain challenging in many cases. Interpretation: Our results illustrate current hardships and possible solutions to monitoring T cell responses to individual chemical skin sensitizers. The provided data can guide the further development of T cell assays to unfold their full predictive and diagnostic potential, including cross-reactivity assessments.

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The C-class chemokine, lymphotactin, impairs the induction of Th1-type lymphokines in human CD4+ T cells

Blood ◽

10.1182/blood.v96.2.420 ◽

2000 ◽

Vol 96 (2) ◽

pp. 420-428 ◽

Cited By ~ 25

Author(s):

Chantal Cerdan ◽

Edgar Serfling ◽

Daniel Olive

Keyword(s):

Cell Proliferation ◽

T Cells ◽

T Cell ◽

T Cell Activation ◽

Cell Activation ◽

Cd8 T Cell ◽

Jurkat Cells ◽

Cd4 T Cell ◽

T Cell Proliferation ◽

Human T Cell

Abstract Chemokines are involved in the regulation of leukocyte migration and for some of them, T-cell costimulation. To date, the only direct property of lymphotactin (Lptn), the unique member of the C class of chemokines, consists of T-cell chemoattraction. This report describes a novel function for Lptn in human T-lymphocyte biology, by demonstrating the direct ability of Lptn to both inhibit and costimulate CD4+ and CD8+ T-cell activation, respectively. Lptn but not RANTES inhibited CD4+ T-cell proliferation, through a decreased production of Th1 (interleukin [IL]-2, interferon [IFN]-γ) but not Th2 (IL-4, IL-13) lymphokines, and decreased IL-2R expression. Transfections in Jurkat cells showed a Lptn-mediated transcriptional down-regulation of gene-promoter activities specific for Th1-type lymphokines, as well as of nuclear factor of activated T cells (NF-AT) but not AP-1 or NF-ΚB enhancer activities. This suppressive action of Lptn could be compensated by overexpression of NF-ATc but not NF-ATp. CD4+ T-cell proliferation was completely restored by exogenous IL-2 or reversed by pertussis toxin, wortmannin, and genistein, suggesting the involvement of multiple partners in Lptn signaling. In contrast to CD4+ cells, Lptn exerted a potent costimulatory activity on CD8+ T-cell proliferation and IL-2 secretion. These data provide important insights into the role of Lptn in differential regulation of normal human T-cell activation and its possible implication in immune response disorders.

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