scholarly journals PARP-1/PARP-2 double deficiency in mouse T cells results in faulty immune responses and T lymphomas

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Judith Navarro ◽  
Beatriz Gozalbo-López ◽  
Andrea C. Méndez ◽  
Françoise Dantzer ◽  
Valérie Schreiber ◽  
...  
Keyword(s):  
T Cells ◽  
Immune Responses ◽  
T Lymphomas ◽  
Parp 1

Aryloxy Triester Phosphonamidates of Phosphoantigens Exhibit Favorable Stability and Potent Activation of Vγ9/Vδ2 T‐Cells

2018 ◽  
Author(s):  
Hachemi Kadri ◽  
Taher E. Taher ◽  
Qin Xu ◽  
Richard T. Bryan ◽  
Benjamin E. Willcox ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Immune Responses ◽  
Serum Stability ◽  
T Cell Immune Responses ◽  
Further Development

We previously reported the application of the aryloxy triester phosphoramidate prodrug technology to the phosphoantigen (E)-4-hydroxybut-2-enyl phosphate (HMBP). Although these prodrugs exhibited potent activation of Vγ9/Vδ2 T‐cell immune responses, their stability was low due to the rapid cleavage of the -O-P- bond. To address this, we herein report the application of the same prodrug strategy to two HMBP phosphonates, which have stable -CH2-P- or -CF2-P- bonds. These HMBP phosphonate prodrugs, phosphonamidates, exhibited excellent serum stability and potent activation of Vgama9/Vdelta2 T‐cells making them attractive compounds for further development as potential immunotherapeutics.

Aryloxy Triester Phosphonamidates of Phosphoantigens Exhibit Favorable Stability and Potent Activation of Vγ9/Vδ2 T‐Cells

2018 ◽  
Author(s):  
Hachemi Kadri ◽  
Taher E. Taher ◽  
Qin Xu ◽  
Richard T. Bryan ◽  
Benjamin E. Willcox ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Immune Responses ◽  
Serum Stability ◽  
T Cell Immune Responses ◽  
Further Development

We previously reported the application of the aryloxy triester phosphoramidate prodrug technology to the phosphoantigen (E)-4-hydroxybut-2-enyl phosphate (HMBP). Although these prodrugs exhibited potent activation of Vγ9/Vδ2 T‐cell immune responses, their stability was low due to the rapid cleavage of the -O-P- bond. To address this, we herein report the application of the same prodrug strategy to two HMBP phosphonates, which have stable -CH2-P- or -CF2-P- bonds. These HMBP phosphonate prodrugs, phosphonamidates, exhibited excellent serum stability and potent activation of Vgama9/Vdelta2 T‐cells making them attractive compounds for further development as potential immunotherapeutics.

scholarly journals The immune response of T cells and therapeutic targets related to regulating the levels of T helper cells after ischaemic stroke

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Tian-Yu Lei ◽  
Ying-Ze Ye ◽  
Xi-Qun Zhu ◽  
Daniel Smerin ◽  
Li-Juan Gu ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cells ◽  
Immune System ◽  
Immune Responses ◽  
Ischaemic Stroke ◽  
Immune Cells ◽  
Tissue Injury ◽  
Recovery Period ◽  
Vital Functions ◽  
Anti Inflammatory

AbstractThrough considerable effort in research and clinical studies, the immune system has been identified as a participant in the onset and progression of brain injury after ischaemic stroke. Due to the involvement of all types of immune cells, the roles of the immune system in stroke pathology and associated effects are complicated. Past research concentrated on the functions of monocytes and neutrophils in the pathogenesis of ischaemic stroke and tried to demonstrate the mechanisms of tissue injury and protection involving these immune cells. Within the past several years, an increasing number of studies have elucidated the vital functions of T cells in the innate and adaptive immune responses in both the acute and chronic phases of ischaemic stroke. Recently, the phenotypes of T cells with proinflammatory or anti-inflammatory function have been demonstrated in detail. T cells with distinctive phenotypes can also influence cerebral inflammation through various pathways, such as regulating the immune response, interacting with brain-resident immune cells and modulating neurogenesis and angiogenesis during different phases following stroke. In view of the limited treatment options available following stroke other than tissue plasminogen activator therapy, understanding the function of immune responses, especially T cell responses, in the post-stroke recovery period can provide a new therapeutic direction. Here, we discuss the different functions and temporal evolution of T cells with different phenotypes during the acute and chronic phases of ischaemic stroke. We suggest that modulating the balance between the proinflammatory and anti-inflammatory functions of T cells with distinct phenotypes may become a potential therapeutic approach that reduces the mortality and improves the functional outcomes and prognosis of patients suffering from ischaemic stroke.

scholarly journals Human fetal liver MSCs are more effective than adult bone marrow MSCs for their immunosuppressive, immunomodulatory, and Foxp3+ T reg induction capacity

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yi Yu ◽  
Alejandra Vargas Valderrama ◽  
Zhongchao Han ◽  
Georges Uzan ◽  
Sina Naserian ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
Immune Responses ◽  
Molecular Mechanisms ◽  
Fetal Liver ◽  
Cytotoxic T Cells ◽  
Cell Contact ◽  
Adult Bone Marrow ◽  
Adult Bone

Abstract Background Mesenchymal stem cells (MSCs) exhibit active abilities to suppress or modulate deleterious immune responses by various molecular mechanisms. These cells are the subject of major translational efforts as cellular therapies for immune-related diseases and transplantations. Plenty of preclinical studies and clinical trials employing MSCs have shown promising safety and efficacy outcomes and also shed light on the modifications in the frequency and function of regulatory T cells (T regs). Nevertheless, the mechanisms underlying these observations are not well known. Direct cell contact, soluble factor production, and turning antigen-presenting cells into tolerogenic phenotypes, have been proposed to be among possible mechanisms by which MSCs produce an immunomodulatory environment for T reg expansion and activity. We and others demonstrated that adult bone marrow (BM)-MSCs suppress adaptive immune responses directly by inhibiting the proliferation of CD4+ helper and CD8+ cytotoxic T cells but also indirectly through the induction of T regs. In parallel, we demonstrated that fetal liver (FL)-MSCs demonstrates much longer-lasting immunomodulatory properties compared to BM-MSCs, by inhibiting directly the proliferation and activation of CD4+ and CD8+ T cells. Therefore, we investigated if FL-MSCs exert their strong immunosuppressive effect also indirectly through induction of T regs. Methods MSCs were obtained from FL and adult BM and characterized according to their surface antigen expression, their multilineage differentiation, and their proliferation potential. Using different in vitro combinations, we performed co-cultures of FL- or BM-MSCs and murine CD3+CD25−T cells to investigate immunosuppressive effects of MSCs on T cells and to quantify their capacity to induce functional T regs. Results We demonstrated that although both types of MSC display similar cell surface phenotypic profile and differentiation capacity, FL-MSCs have significantly higher proliferative capacity and ability to suppress both CD4+ and CD8+ murine T cell proliferation and to modulate them towards less active phenotypes than adult BM-MSCs. Moreover, their substantial suppressive effect was associated with an outstanding increase of functional CD4+CD25+Foxp3+ T regs compared to BM-MSCs. Conclusions These results highlight the immunosuppressive activity of FL-MSCs on T cells and show for the first time that one of the main immunoregulatory mechanisms of FL-MSCs passes through active and functional T reg induction.

scholarly journals Immunomodulating nano-adaptors potentiate antibody-based cancer immunotherapy

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Cheng-Tao Jiang ◽  
Kai-Ge Chen ◽  
An Liu ◽  
Hua Huang ◽  
Ya-Nan Fan ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Immune Responses ◽  
Cancer Immunotherapy ◽  
Tumor Cells ◽  
Noncovalent Interactions ◽  
Killer Cell ◽  
Antibody Immobilization ◽  
Effector Cells ◽  
Nanoparticle Surface

AbstractModulating effector immune cells via monoclonal antibodies (mAbs) and facilitating the co-engagement of T cells and tumor cells via chimeric antigen receptor- T cells or bispecific T cell-engaging antibodies are two typical cancer immunotherapy approaches. We speculated that immobilizing two types of mAbs against effector cells and tumor cells on a single nanoparticle could integrate the functions of these two approaches, as the engineered formulation (immunomodulating nano-adaptor, imNA) could potentially associate with both cells and bridge them together like an ‘adaptor’ while maintaining the immunomodulatory properties of the parental mAbs. However, existing mAbs-immobilization strategies mainly rely on a chemical reaction, a process that is rough and difficult to control. Here, we build up a versatile antibody immobilization platform by conjugating anti-IgG (Fc specific) antibody (αFc) onto the nanoparticle surface (αFc-NP), and confirm that αFc-NP could conveniently and efficiently immobilize two types of mAbs through Fc-specific noncovalent interactions to form imNAs. Finally, we validate the superiority of imNAs over the mixture of parental mAbs in T cell-, natural killer cell- and macrophage-mediated antitumor immune responses in multiple murine tumor models.

scholarly journals 413 GEN-009, a personalized neoantigen vaccine, elicits robust immune responses in individuals with advanced or metastatic solid tumors

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A438-A438
Author(s):  
Mara Shainheit ◽  
Devin Champagne ◽  
Gabriella Santone ◽  
Syukri Shukor ◽  
Ece Bicak ◽  
...  
Keyword(s):  
Clinical Trial ◽  
T Cells ◽  
T Cell ◽  
Immune Responses ◽  
Solid Tumors ◽  
Ex Vivo ◽  
T Cell Responses ◽  
Checkpoint Blockade ◽  
T Cell Subsets ◽  
Cell Responses

BackgroundATLASTM is a cell-based bioassay that utilizes a cancer patient‘s own monocyte-derived dendritic cells and CD4+ and CD8+ T cells to screen their mutanome and identify neoantigens that elicit robust anti-tumor T cell responses, as well as, deleterious InhibigensTM.1 GEN-009, a personalized vaccine comprised of 4–20 ATLAS-identified neoantigens combined with Hiltonol®, harnesses the power of neoantigen-specific T cells to treat individuals with solid tumors. The safety and efficacy of GEN-009 is being assessed in a phase 1/2a clinical trial (NCT03633110).MethodsA cohort of 15 adults with solid tumors were enrolled in the study. During the screening period, patients received standard of care PD-1-based immunotherapies appropriate for their tumor type. Subsequently, patients were immunized with GEN-009 with additional doses administered at 3, 6, 12, and 24 weeks. Peripheral blood mononuclear cells (PBMCs) were collected at baseline, pre-vaccination (D1), as well as 29, 50, 92, and 176 days post first dose. Vaccine-induced immunogenicity and persistence were assessed by quantifying neoantigen-specific T cell responses in ex vivo and in vitro stimulation dual-analyte fluorospot assays. Polyfunctionality of neoantigen-specific T cells was evaluated by intracellular cytokine staining. Additionally, potential correlations between the ATLAS-identified profile and vaccine-induced immunogenicity were assessed.ResultsGEN-009 augmented T cell responses in 100% of evaluated patients, attributable to vaccine and not checkpoint blockade. Furthermore, neoantigen-induced secretion of IFNγ and/or TNFα by PBMCs, CD4+, and CD8+ T cells was observed in all patients. Responses were primarily from polyfunctional TEM cells and detectable in both CD4+ and CD8+ T cell subsets. Some patients had evidence of epitope spreading. Unique response patterns were observed for each patient with no apparent relationship between tumor types and time to emergence, magnitude or persistence of response. Ex vivo vaccine-induced immune responses were observed as early as 1 month, and in some cases, persisted for 176 days. Clinical efficacy possibly attributable to GEN-009 was observed in several patients, but no correlation has yet been identified with neoantigen number or magnitude of immune response.ConclusionsATLAS empirically identifies stimulatory neoantigens using the patient‘s own immune cells. GEN-009, which is comprised of personalized, ATLAS-identified neoantigens, elicits early, long-lasting and polyfunctional neoantigen-specific CD4+ and CD8+ T cell responses in individuals with advanced cancer. Several patients achieved clinical responses that were possibly attributable to vaccine; efforts are underway to explore T cell correlates of protection. These data support that GEN-009, in combination with checkpoint blockade, represents a unique approach to treat solid tumors.AcknowledgementsWe are grateful to the patients and their families who consented to participate in the GEN-009-101 clinical trial.Trial RegistrationNCT03633110Ethics ApprovalThis study was approved by Western Institutional Review Board, approval number 1-1078861-1. All subjects contributing samples provided signed individual informed consent.ReferenceDeVault V, Starobinets H, Adhikari S, Singh S, Rinaldi S, Classon B, Flechtner J, Lam H. Inhibigens, personal neoantigens that drive suppressive T cell responses, abrogate protection of therapeutic anti-tumor vaccines. J. Immunol 2020; 204(1 Supplement):91.15.

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