Immunotherapy strategies aim to mobilize immune defenses against tumor cells by targeting mainly T cells. Co‐inhibitory receptors or immune checkpoints (ICPs) (such as PD-1 and CTLA4) can limit T cell receptor (TCR) signal propagation in... more
Immunotherapy strategies aim to mobilize immune defenses against tumor cells by targeting mainly T cells. Co‐inhibitory receptors or immune checkpoints (ICPs) (such as PD-1 and CTLA4) can limit T cell receptor (TCR) signal propagation in T cells. Antibody-based blocking of immune checkpoints (immune checkpoint inhibitors, ICIs) enable escape from ICP inhibition of TCR signaling. ICI therapies have significantly impacted the prognosis and survival of patients with cancer. However, many patients remain refractory to these treatments. Thus, alternative approaches for cancer immunotherapy are needed. In addition to membrane‐associated inhibitory molecules, a growing number of intracellular molecules may also serve to downregulate signaling cascades triggered by TCR engagement. These molecules are known as intracellular immune checkpoints (iICPs). Blocking the expression or the activity of these intracellular negative signaling molecules is a novel field of action to boost T cell-mediate...
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TNFRF-14/HVEM is the ligand for BTLA and CD160 negative immune co-signaling molecules as well as viral proteins. Its expression is dysregulated with an overexpression in tumors and a connection with tumors of adverse prognosis. We... more
TNFRF-14/HVEM is the ligand for BTLA and CD160 negative immune co-signaling molecules as well as viral proteins. Its expression is dysregulated with an overexpression in tumors and a connection with tumors of adverse prognosis. We developed C57BL/6 mouse models co-expressing human huBTLA and huHVEM as well as antagonistic monoclonal antibodies (mAbs) that completely prevent the interactions of HVEM with its ligands. Here, we show that the anti-HVEM18-10 mAb increases primary human αβ-T cells activity alone (CIS-activity) or in the presence of HVEM-expressing lung or colorectal cancer cells in vitro (TRANS-activity). Anti-HVEM18-10 synergizes with anti-PD-L1 mAb to activate T cells in the presence of PDL-1 positive tumors, but is sufficient to trigger T cell activation in the presence of PD-L1 negative cells. In order to better understand HVEM18-10 effect in vivo and especially disentangle its CIS and TRANS effects, we developed a knock-in (KI) mouse model expressing human BTLA (huBTLA+/+) and a KI mouse model expressing both human BTLA and human HVEM (huBTLA+/+/huHVEM+/+ (DKI)). In vivo pre-clinical experiments performed in both mouse models showed that HVEM18-10 treatment was efficient to decrease human HVEM+ tumor growth. In the DKI model, anti-HVEM 18-10 treatment induces a decrease of exhausted CD8+ T cells and regulatory T cells and an increase of Effector memory CD4+ T cells within the tumor. Interestingly, mice which completely rejected tumors (± 20%) did not develop tumors upon re-challenge in both settings, therefore showing a marked T cell-memory phenotype effect. Altogether, our preclinical models validate anti-HVEM18-10 as a promising therapeutic antibody to use in clinics as a monotherapy or in combination with existing immunotherapies (anti-PD1/anti-PDL-1/anti-CTLA-4). Citation Format: Laurent GORVEL, Clemence Demerle, Marielle Mello, Sonia Pastor, Clara Degos, Ana Zarubica, Fabien Angelis, Frederic Fiore, Jacques Nunes, Bernard Malissen, Laurent Greillier, Geoffrey Guittard, Herve Luche, Fabrice Barlesi, Daniel Olive. Anti-HVEM mAb therapy improves antitumoral immunity both in vitro and in vivo, in a novel transgenic mouse model expressing human HVEM and BTLA molecules challenged with HVEM expressing tumors. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5184.
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BackgroundTNFRF-14/HVEM is the ligand for BTLA and CD160 negative immune co-signaling molecules as well as viral proteins. Its expression is dysregulated with an overexpression in tumors and a connection with tumors of adverse... more
BackgroundTNFRF-14/HVEM is the ligand for BTLA and CD160 negative immune co-signaling molecules as well as viral proteins. Its expression is dysregulated with an overexpression in tumors and a connection with tumors of adverse prognosis.MethodsWe developed C57BL/6 mouse models co-expressing human huBTLA and huHVEM as well as antagonistic monoclonal antibodies (mAbs) that completely prevent the interactions of HVEM with its ligands.ResultsHere, we show that the anti-HVEM18-10 mAb increases primary human αß-T cells activity alone (CIS-activity) or in the presence of HVEM-expressing lung or colorectal cancer cellsin vitro(TRANS-activity). Anti-HVEM18-10 synergizes with anti-PD-L1 mAb to activate T cells in the presence of PDL-1 positive tumors, but is sufficient to trigger T cell activation in the presence of PD-L1 negative cells. In order to better understand HVEM18-10 effectin vivoand especially disentangle its CIS and TRANS effects, we developed a knock-in (KI) mouse model expressin...
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ABSTRACTTargeting intracellular inhibiting proteins is a promising strategy to improve CD8+ T cell anti-tumor efficacy. DOK1 and DOK2 are CD8+ T cell inhibitory proteins that are targeted in this study in order to improve the activation... more
ABSTRACTTargeting intracellular inhibiting proteins is a promising strategy to improve CD8+ T cell anti-tumor efficacy. DOK1 and DOK2 are CD8+ T cell inhibitory proteins that are targeted in this study in order to improve the activation and cytotoxic capacities of these cells. To evaluate the role of DOK-1 and DOK-2 depletion in physiology and effector function of T CD8+ lymphocyte and in cancer progression, a transgenic T cell receptor mouse model specific to melanoma antigen hgp100 (pmel-1 TCR Tg) was established.Depletion of both Dok1 and Dok2 did not affect the development, proliferation, mortality, activation and cytotoxic function of naive CD8+ T cells. However, after an in vitro pre-stimulation Dok1/Dok2 DKO CD8+ T cells had higher percentage of effector memory T cells and showed an increase in levels of pAKT and pERK upon TCR stimulation. Despite this improved TCR signaling, pre-stimulated Dok1/Dok2 DKO CD8+ T cells did not show any increase in their activation or cytotoxici...
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ABSTRACTNatural killer (NK) cells are major anti-leukemic immune effectors. Leukemic blasts have a negative impact on NK cell function and promote the emergence of phenotypically and functionally impaired NK cells. In the present work, we... more
ABSTRACTNatural killer (NK) cells are major anti-leukemic immune effectors. Leukemic blasts have a negative impact on NK cell function and promote the emergence of phenotypically and functionally impaired NK cells. In the present work, we highlight an accumulation of CD56-CD16+unconventional NK cells in acute myeloid leukemia (AML), an aberrant subset initially described as being elevated in patients chronically infected with HIV-1. Deep phenotyping of NK cells was performed using peripheral blood from patients with newly-diagnosed AML (N=48, HEMATOBIO cohort,NCT02320656) and healthy subjects (N=18) by mass cytometry. We evidenced a moderate to drastic accumulation of CD56-CD16+unconventional NK cells in 27% of patients. These NK cells displayed decreased expression of NKG2A as well as the triggering receptors NKp30, and NKp46, in line with previous observations in HIV-infected patients. High-dimensional characterization of these NK cells highlighted a decreased expression of three ...
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The regulation of early and late events of T cell activation via the CD28 molecule has been investigated, using as an indicator system the differentiated leukemic T cell line Jurkat. Both CD3 and CD28 mAbs induced an increase in (Ca2+)i... more
The regulation of early and late events of T cell activation via the CD28 molecule has been investigated, using as an indicator system the differentiated leukemic T cell line Jurkat. Both CD3 and CD28 mAbs induced an increase in (Ca2+)i in Jurkat cells, although with different kinetics, the latter being slower than the former. CD28-mediated (Ca2+)i mobilization was highly sensitive to cholera toxin (ID50 25 ng/ml, vs 300 ng/ml for CD3 stimulation). The inhibitory action of cholera toxin was neither merely due to the increase in intracellular cAMP concentrations, nor to decrease in cell surface expression of the CD28 molecule. To evaluate the effects of cholera toxin on late events of Jurkat cell activation induced by CD28 and CD3 mAbs, the action of cholera toxin and cAMP and CD3- and CD28-mediated IL-2 secretion was analyzed. CD3-induced IL-2 secretion was highly sensitive to cholera toxin (ID less than 5 ng/ml); on the other hand, CD28-induced IL-2 secretion was poorly sensitive to cholera toxin, in sharp contrast to (Ca2+)i mobilization. On the basis of these data, it is hypothesized that the CD28 pathway could be associated with at least two distinct transduction mechanisms, one responsible for the (Ca2+)i rise in Jurkat cells and highly sensitive to cholera toxin, and the other, whose second messenger is unknown, resistant to cholera toxin and responsible for IL-2 secretion.
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Strategies are being explored to increase the efficiency of immune checkpoint inhibitors (ICIs) targeting PD1/PDL1 in triple-negative breast cancer (TNBC), including combination with therapies inhibiting intracellular immune checkpoints... more
Strategies are being explored to increase the efficiency of immune checkpoint inhibitors (ICIs) targeting PD1/PDL1 in triple-negative breast cancer (TNBC), including combination with therapies inhibiting intracellular immune checkpoints such as CISH (Cytokine-induced SH2 protein). Correlation between CISH expression and TNBC features is unknown. We retrospectively analyzed CISH expression in 1936 clinical TNBC samples and searched for correlations with clinical variables, including metastasis-free interval (MFI). Among TNBCs, 44% were identified as “CISH-up” and 56% “CISH-down”. High expression was associated with pathological axillary lymph node involvement, more adjuvant chemotherapy, and Lehmann’s immunomodulatory and luminal AR subtypes. The “CISH-up” class showed longer 5-year MFI (72%) than the “CISH-down” class (60%; p = 2.8 × 10−2). CISH upregulation was associated with activation of IFNα and IFNγ pathways, antitumor cytotoxic immune response, and signatures predictive for I...
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3Address correspondence and reprint requests to Dr. Jacques A. Nunès, Centre de Recherche en Cancérologie de
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Cytokine inducible SH2-containing protein (CISH) is a natural killer (NK) cell negative regulator of cytokine signaling pathway. To further understand CISH functions in NK cells, we developed a conditional Cish-deficient mouse model in NK... more
Cytokine inducible SH2-containing protein (CISH) is a natural killer (NK) cell negative regulator of cytokine signaling pathway. To further understand CISH functions in NK cells, we developed a conditional Cish-deficient mouse model in NK cells (Cishfl/flNcr1Ki/+). We detected no developmental or homeostatic difference in NK cells.However, global gene expression of Cishfl/flNcr1Ki/+ NK cells compared to Cish+/+Ncr1Ki/+ NK cells revealed upregulation of pathways and genes associated with NK cell cycling and activation. We show that CISH does not only regulate interleukin-15 (IL-15) signaling pathways but also natural cytotoxicity receptors (NCR) pathways. Indeed, CISH protein expression level increases upon NCR triggering. Primed Cishfl/flNcr1Ki/+ NK cells display increased activation upon NCR stimulation. Cishfl/flNcr1Ki/+ NK cells display lower activation thresholds and Cishfl/flNcr1Ki/+ mice are more resistant to tumor metastasis. Remarkably, we found that Cishfl/flNcr1Ki/+ mice w...
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Signaling through the αβT cell receptor (TCR) is a crucial determinant of T-cell fate and can induce two opposite outcomes during thymocyte development: cell death or survival and differentiation. To date, the role played by T cell... more
Signaling through the αβT cell receptor (TCR) is a crucial determinant of T-cell fate and can induce two opposite outcomes during thymocyte development: cell death or survival and differentiation. To date, the role played by T cell receptor in the oncogenic transformation of developing T-cells remains unclear. Here we show that human primary T-cell acute lymphoblastic leukemias expressing a αβT cell receptor are frequently deficient for phosphatase and tensin homolog protein (PTEN), and fail to strongly respond to T cell receptor activation. Using Pten-deficient T-cell acute lymphoblastic leukemia mouse models, we confirm that T cell receptor signaling is involved in leukemogenesis. We show that abrogation of T cell receptor expression accelerated tumor onset, while enforced expression of a fit transgenic T cell receptor led to the development of T cell receptor-negative lymphoma and delayed tumorigenesis. We further demonstrate that pre-tumoral Pten-deficient thymocytes harboring f...
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Accumulating evidence highlights natural killer (NK) cell parameters as potential prognostic factors in cancer patients, which provides a strong rationale for developing therapeutic strategies aiming at restoring NK cell. However,... more
Accumulating evidence highlights natural killer (NK) cell parameters as potential prognostic factors in cancer patients, which provides a strong rationale for developing therapeutic strategies aiming at restoring NK cell. However, reaching this point warrants better characterization of tumor-induced NK cell alterations. Our group recently reported heterogeneous NK maturation in acute myeloid leukemia (AML) patients. However, the clinical significance of such observations remained to be assessed on a larger cohort of patients. NK maturation based on expression of CD56, CD57, and KIR was assessed by flow cytometry in newly diagnosed AML patients (N = 87 patients from GOELAMS-LAM-IR-2006 multicenter trial). Clinical outcome was evaluated with regard to NK maturation profiles. Unsupervised integrated analysis of NK maturation markers confirmed the existence of three distinct groups of patients [hypomaturation (24.1%), intermediate maturation (66.7%), and hypermaturation (9.2%)]. In univ...
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... 3. LJ Berg, LD Finkelstein, JA Lucas and PL Schwartzberg, Tec family kinases in T lymphocyte development and function, Annu Rev Immunol 23 ... 5. S. Tsukada, DJ Rawlings and ON Witte, Role of Bruton's tyrosine kinase in... more
... 3. LJ Berg, LD Finkelstein, JA Lucas and PL Schwartzberg, Tec family kinases in T lymphocyte development and function, Annu Rev Immunol 23 ... 5. S. Tsukada, DJ Rawlings and ON Witte, Role of Bruton's tyrosine kinase in im-munodeficiency, Curr Opin Immunol 6(4), 623–630 ...
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Crosslinking of regulatory immunoreceptors (RR), such as BDCA-2 (CD303) or ILT7 (CD85g), of plasmacytoid dendritic cells (pDCs) efficiently suppresses production of type-I interferon (IFN)-α/β and other cytokines in response to Toll-like... more
Crosslinking of regulatory immunoreceptors (RR), such as BDCA-2 (CD303) or ILT7 (CD85g), of plasmacytoid dendritic cells (pDCs) efficiently suppresses production of type-I interferon (IFN)-α/β and other cytokines in response to Toll-like receptor (TLR) 7/9 ligands. This cytokine-inhibitory pathway is mediated by spleen tyrosine kinase (Syk) associated with the ITAM-containing adapter of RR. Here we demonstrate by pharmacological targeting of Syk that in addition to the negative regulation of TLR7/9 signaling via RR, Syk also positively regulates the TLR7/9 pathway in human pDCs. Novel highly specific Syk inhibitor AB8779 suppressed IFN-α, TNF-α and IL-6 production induced by TLR7/9 agonists in primary pDCs and in the pDC cell line GEN2.2. Triggering of TLR9 or RR signaling induced a differential kinetics of phosphorylation at Y352 and Y525/526 of Syk and a differential sensitivity to AB8779. Consistent with the different roles of Syk in TLR7/9 and RR signaling, a concentration of AB...
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Research Interests: Genetics, Immunology, Biology, T cell receptor, Immunity, and 4 moreT Cell, CD, Spectrum, and T cell activation
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Research Interests: Biology, Leukemia, Cell Signaling, Cancer Research, Humans, and 15 moreFemale, Animals, Male, Gene, Haploinsufficiency, Clinical Sciences, Aged, Adult, Dok, Chronic Myeloprolifrative Neoplasms, DNA binding proteins, Chronic Myelomonocytic Leukemia, Bone Marrow Cells, Cohort Studies, and DNA mutational analysis
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Research Interests: Biology, Gene Therapy, Gene expression, Genetic Engineering, Biological Sciences, and 15 moreHematopoietic Stem Cells, Cell therapy, Cell line, Humans, Genetic Enhancement, Cord Blood, Animals, Bone marrow, Green Fluorescent Protein, Btk, B Lymphocytes, Gene Transfer, Agammaglobulinemia, Genetic Therapy, and B cell
The signaling function of the T cell antigen receptor (TCR) is mediated via CD3 polypeptides, the cytoplasmic sequences of which bear conserved immunoreceptor tyrosine-based activation motifs (ITAM). ITAM are defined by two YxxL/I... more
The signaling function of the T cell antigen receptor (TCR) is mediated via CD3 polypeptides, the cytoplasmic sequences of which bear conserved immunoreceptor tyrosine-based activation motifs (ITAM). ITAM are defined by two YxxL/I sequences separated by a six-eight amino acid long spacer. Upon antigen recognition, ITAM become phosphorylated on both tyrosine residues, creating a high affinity binding site for the tandem SH2 domains found in the protein tyrosine kinase ZAP-70. Using surface plasmon resonance, we further dissected the sequences required for the binding of ZAP-70 to each TCR-associated ITAM. First, we generated protein tyrosine phosphatase-resistant ITAM peptide analogs, in which difluorophosphonomethyl phenylalanyl (F2p) replaced both phosphotyrosines, and showed that those protein tyrosine phosphatase-resistant analogs bind ZAP-70 with high affinity, establishing a rational strategy for the design of novel pharmacological tools capable of interfering with TCR signaling function. Second, we substituted the five amino acids separating the two YxxL/I sequences of the CD3 zeta 1 ITAM with a non-peptidic linker made up of gamma-amino butyric acid units and demonstrated that the length of this intervening sequence rather than its chemical composition is essential for high affinity binding of phosphorylated ITAM to the ZAP-70 SH2 domains.
Research Interests: Biochemistry, Immunology, Biology, T Cell biology, Medicine, and 14 moreMacromolecular X-Ray Crystallography, Humans, Surface plasmon resonance, Peptides, Protein tyrosine phosphatase, Phosphotyrosine, European, Biacore, Amino Acid Sequence, Protein Binding, Biosensing Techniques, Tyrosine, Molecular Sequence Data, and Protein tyrosine kinases
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Immunotherapies targeting the “don’t eat me” myeloid checkpoint constituted by CD47 SIRPα interaction have promising clinical potential but are limited by toxicities associated with the destruction of non-tumor cells. These dose-limiting... more
Immunotherapies targeting the “don’t eat me” myeloid checkpoint constituted by CD47 SIRPα interaction have promising clinical potential but are limited by toxicities associated with the destruction of non-tumor cells. These dose-limiting toxicities demonstrate the need to highlight the mechanisms of anti-CD47-SIRPα therapy effects on non-tumor CD47-bearing cells. Given the increased incidence of lymphopenia in patients receiving anti-CD47 antibodies, and the strong ADCC effector function of Poly Morpho Nuclear Cells (PMNs), we investigated the behavior of primary PMNs cocultured with primary T cells in the presence of anti-CD47 mAbs. PMNs killed T cells in a CD47-mAb-dependent manner and at a remarkably potent PMN to T cell ratio of 1:1. The observed cytotoxicity was produced by a novel combination of both trogocytosis and a strong respiratory burst induced by classical ADCC and CD47-SIRPα checkpoint blockade. The complex effect of the CD47 blocking mAb could be recapitulated by com...
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Simple Summary Vδ2+ γδ T cells have potent antitumor properties both in vitro and in murine preclinical models of breast cancers. However, in the context of human breast cancer, there is a lack of information for potential phenotypic... more
Simple Summary Vδ2+ γδ T cells have potent antitumor properties both in vitro and in murine preclinical models of breast cancers. However, in the context of human breast cancer, there is a lack of information for potential phenotypic alterations of this crucial immune cell subset. This is partly due to Vδ2+ γδ T cells scarcity in surgical specimens. To break this deadlock, we assessed Vδ2+ γδ T cell phenotypes using untreated breast cancer patients’ peripheral blood, so-called minimally invasive “liquid biopsy”. We show that circulating Vδ2+ γδ T cell phenotypic alterations are already established at diagnosis and related to tumor progression. Notably, terminally differentiated Vδ2+ γδ T cells expressing canonical markers of replicative senescence and exhaustion were significantly associated with tumor-draining lymph node invasion. Our results shed light on the interest of using liquid biopsy to monitor rare events and support Vδ2+ γδ T cell involvement in breast cancer pathogenesis...