Myeloid dendritic cell precursors generated from bone marrow suppress T cell responses via cell contact and nitric oxide productionin vitro

ObjectiveSolid tumours respond poorly to immune checkpoint inhibitor (ICI) therapies. One major therapeutic obstacle is the immunosuppressive tumour microenvironment (TME). Cancer-associated fibroblasts (CAFs) are a key component of the TME and negatively regulate antitumour T-cell response. Here, we aimed to uncover the mechanism underlying CAFs-mediated tumour immune evasion and to develop novel therapeutic strategies targeting CAFs for enhancing ICI efficacy in oesophageal squamous cell carcinoma (OSCC) and colorectal cancer (CRC).DesignAnti-WNT2 monoclonal antibody (mAb) was used to treat immunocompetent C57BL/6 mice bearing subcutaneously grafted mEC25 or CMT93 alone or combined with anti-programmed cell death protein 1 (PD-1), and the antitumour efficiency and immune response were assessed. CAFs-induced suppression of dendritic cell (DC)-differentiation and DC-mediated antitumour immunity were analysed by interfering with CAFs-derived WNT2, either by anti-WNT2 mAb or with short hairpin RNA-mediated knockdown. The molecular mechanism underlying CAFs-induced DC suppression was further explored by RNA-sequencing and western blot analyses.ResultsA negative correlation between WNT2+ CAFs and active CD8+ T cells was detected in primary OSCC tumours. Anti-WNT2 mAb significantly restored antitumour T-cell responses within tumours and enhanced the efficacy of anti-PD-1 by increasing active DC in both mouse OSCC and CRC syngeneic tumour models. Directly interfering with CAFs-derived WNT2 restored DC differentiation and DC-mediated antitumour T-cell responses. Mechanistic analyses further demonstrated that CAFs-secreted WNT2 suppresses the DC-mediated antitumour T-cell response via the SOCS3/p-JAK2/p-STAT3 signalling cascades.ConclusionsCAFs could suppress antitumour immunity through WNT2 secretion. Targeting WNT2 might enhance the ICI efficacy and represent a new anticancer immunotherapy.

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Dendritic cell subsets generated from CD34+ hematopoietic progenitors can be transfected with mRNA and induce antigen-specific cytotoxic T cell responses

Journal of Immunological Methods ◽

10.1016/j.jim.2003.11.012 ◽

2004 ◽

Vol 285 (2) ◽

pp. 171-180 ◽

Cited By ~ 22

Author(s):

Hideki Ueno ◽

Irina Tcherepanova ◽

Olivier Reygrobellet ◽

Erik Laughner ◽

Claire Ventura ◽

...

Keyword(s):

T Cell ◽

Dendritic Cell ◽

T Cell Responses ◽

Cytotoxic T Cell ◽

Hematopoietic Progenitors ◽

Cell Responses ◽

Dendritic Cell Subsets ◽

Cytotoxic T Cell Responses

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Dendritic Cell Targeting Effectively Boosts T Cell Responses Elicited by an HIV Multiepitope DNA Vaccine

Frontiers in Immunology ◽

10.3389/fimmu.2017.00101 ◽

2017 ◽

Vol 8 ◽

Cited By ~ 12

Author(s):

Juliana de Souza Apostólico ◽

Victória Alves Santos Lunardelli ◽

Marcio Massao Yamamoto ◽

Higo Fernando Santos Souza ◽

Edecio Cunha-Neto ◽

...

Keyword(s):

T Cell ◽

Dendritic Cell ◽

Dna Vaccine ◽

T Cell Responses ◽

Cell Targeting ◽

Cell Responses

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TriMix and tumor antigen mRNA electroporated dendritic cell vaccination plus ipilimumab: link between T-cell activation and clinical responses in advanced melanoma

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2019-000329 ◽

2020 ◽

Vol 8 (1) ◽

pp. e000329 ◽

Cited By ~ 3

Author(s):

Brenda De Keersmaecker ◽

Sofie Claerhout ◽

Javier Carrasco ◽

Isabelle Bar ◽

Jurgen Corthals ◽

...

Keyword(s):

T Cell ◽

Dendritic Cell ◽

Clinical Response ◽

T Cell Activation ◽

Peripheral Blood ◽

T Cell Responses ◽

Cd8 T Cell ◽

Advanced Melanoma ◽

Dendritic Cell Vaccination ◽

Cell Responses

BackgroundWe previously reported that dendritic cell-based mRNA vaccination plus ipilimumab (TriMixDC-MEL IPI) results in an encouraging rate of tumor responses in patients with pretreated advanced melanoma. Here, we report the TriMixDC-MEL IPI-induced T-cell responses detected in the peripheral blood.MethodsMonocyte-derived dendritic cells electroporated with mRNA encoding CD70, CD40 ligand, and constitutively active TLR4 (TriMix) as well as the tumor-associated antigens tyrosinase, gp100, MAGE-A3, or MAGE-C2 were administered together with IPI for four cycles. For 18/39 patients, an additional vaccine was administered before the first IPI administration. We evaluated tumor-associated antigen specific T-cell responses in previously collected peripheral blood mononuclear cells, available from 15 patients.ResultsVaccine-induced enzyme-linked immunospot assay responses detected after in vitro T-cell stimulation were shown in 12/15 patients. Immune responses detected in patients with a complete or partial response were significantly stronger and broader, and exhibited a higher degree of multifunctionality compared with responses in patients with stable or progressive disease. CD8+ T-cell responses from patients with an ongoing clinical response, either elicited by TriMixDC-MEL IPI or on subsequent pembrolizumab treatment, exhibited the highest degree of multifunctionality.ConclusionsTriMixDC-MEL IPI treatment results in robust CD8+ T-cell responses in a meaningful portion of stage III or IV melanoma patients, and obviously in patients with a clinical response. The levels of polyfunctional and multiantigen T-cell responses measured in patients with a complete response, particularly in patients evidently cured after 5+ years of follow-up, may provide a benchmark for the level of immune stimulation needed to achieve a durable clinical remission.Trial registration numberNCT01302496.

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Nitric oxide-producing CD11b+Ly-6G(Gr-1)+CD31(ER-MP12)+cells in the spleen of cyclophosphamide–treated mice: implications for T-cell responses in immunosuppressed mice

Blood ◽

10.1182/blood.v95.1.212 ◽

2000 ◽

Vol 95 (1) ◽

pp. 212-220 ◽

Cited By ~ 119

Author(s):

Iñigo Angulo ◽

Federico Gómez de las Heras ◽

José F. Garcı́a-Bustos ◽

Domingo Gargallo ◽

M. Angeles Muñoz-Fernández ◽

...

Keyword(s):

Nitric Oxide ◽

Cell Proliferation ◽

T Cell ◽

T Cell Responses ◽

T Cell Proliferation ◽

Intensive Chemotherapy ◽

Suppressive Activity ◽

Cell Responses ◽

Nos Inhibitors ◽

Ifn Γ

Abstract During recovery from intensive chemotherapy with cyclophosphamide (CTX), mice suffer a severe but transitory impairment in spleen cell proliferation to T-cell mitogens (Con A or anti-CD3 plus IL-2). Although CTX treatment reduced spleen T-cell cellularity, this cannot fully account for T-cell unresponsiveness. The results showed that CTX induces the colonization of spleen by an immature myeloid CD11b+Ly-6G+CD31+ population. Its presence closely correlated with the maximum inhibition of T-cell proliferation. Moreover, this suppressive activity was dependent on nitric oxide (NO) production in cultures since (1) higher amounts of nitric oxide and inducible nitric oxide synthase (iNOS) mRNA were produced in CTX spleen cells (CTX-SC) than in control splenocyte cultures and (2) NOS inhibitors greatly improved the proliferation of T lymphocytes. Nitric oxide production and suppressive activity were also dependent on endogenous interferon-γ (IFN-γ) production since anti–IFN-γ abrogated both effects. Finally, iNOS protein expression was restricted to a heterogeneous population of CD31+cells in which CD11b+Ly-6G+ cells were required to suppress T-cell proliferation. These results indicated that CTX might also cause immunosuppression by a mechanism involving the presence of immature myeloid cells with suppressor activity. This may have implications in clinical praxis since inappropriate immunotherapies in patients treated with intensive chemotherapy could lead to deleterious T-cell responses. (Blood. 2000;95:212-220)

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