Characterization of T-regulatory cells, induced by immature dendritic cells, which inhibit enteroantigen-reactive colitis-inducing T-cell responses in vitro and in vivo

Dendritic cells (DCs) genetically engineered to overexpress CD95 (Fas) ligand (CD95L-DC) were proposed as tools to induce peripheral tolerance to alloantigens. Herein, we observed that CD95L-DC obtained after retroviral gene transfer in bone marrow (BM) precursors derived from CD95-deficient (lpr/lpr) mice elicit much stronger allospecific type 1 helper T-cell and cytotoxic T-cell activities than control DCs upon injection in vivo, although they induce lower T-cell responses in vitro. Indeed, a single injection of CD95L-DC prepared from C57BL/6 mice was sufficient to prime bm13 recipients for acute rejection of C57BL/6 skin allografts that were otherwise tolerated in the context of this single weak major histocompatibility complex (MHC) class I incompatibility. Massive neutrophil infiltrates depending on interleukin (IL)–1 signaling were observed at sites of CD95L-DC injection. Experiments in IL-1 receptor–deficient mice or in animals injected with depleting anti-Gr1 monoclonal antibody (mAb) established that neutrophil recruitment is required for the development of vigorous T-cell responses after injection of CD95L-DC in vivo.

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Plasmacytoid dendritic cells efficiently cross-prime naive T cells in vivo after TLR activation

Blood ◽

10.1182/blood-2008-03-146290 ◽

2008 ◽

Vol 112 (9) ◽

pp. 3713-3722 ◽

Cited By ~ 127

Author(s):

Juliette Mouriès ◽

Gabriel Moron ◽

Géraldine Schlecht ◽

Nicolas Escriou ◽

Gilles Dadaglio ◽

...

Keyword(s):

Dendritic Cells ◽

T Cell ◽

Antigen Processing ◽

Cytotoxic T Lymphocyte ◽

T Cell Responses ◽

Cd8 T Cell ◽

Cross Presentation ◽

Cell Responses

Abstract Cross-presentation is a crucial mechanism in tumoral and microbial immunity because it allows internalized cell associated or exogenous antigens (Ags) to be delivered into the major histocompatibility complex I pathway. This pathway is important for the development of CD8+ T-cell responses and for the induction of tolerance. In mice, cross-presentation is considered to be a unique property of CD8α+ conventional dendritic cells (DCs). Here we show that splenic plasmacytoid DCs (pDCs) efficiently capture exogenous Ags in vivo but are not able to cross-present these Ags at steady state. However, in vitro and in vivo stimulation by Toll-like receptor-7, or -9 or viruses licenses pDCs to cross-present soluble or particulate Ags by a transporter associated with antigen processing-dependent mechanism. Induction of cross-presentation confers to pDCs the ability to generate efficient effector CD8+ T-cell responses against exogenous Ags in vivo, showing that pDCs may play a crucial role in induction of adaptive immune responses against pathogens that do not infect tissues of hemopoietic origin. This study provides the first evidence for an in vivo role of splenic pDCs in Ag cross-presentation and T-cell cross-priming and suggests that pDCs may constitute an attractive target to boost the efficacy of vaccines based on cytotoxic T lymphocyte induction.

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Enhancing the immunostimulatory function of dendritic cells by transfection with mRNA encoding OX40 ligand

Blood ◽

10.1182/blood-2004-10-3944 ◽

2005 ◽

Vol 105 (8) ◽

pp. 3206-3213 ◽

Cited By ~ 77

Author(s):

Jens Dannull ◽

Smita Nair ◽

Zhen Su ◽

David Boczkowski ◽

Christian DeBeck ◽

...

Keyword(s):

Dendritic Cells ◽

T Cell ◽

T Cell Responses ◽

Human Monocyte ◽

Interleukin 12 ◽

T Helper ◽

Cell Responses ◽

Mrna Transfection

Abstract The objective of this study was to investigate whether the immunostimulatory properties of human monocyte-derived dendritic cells (DCs) could be enhanced by triggering OX40/OX40L signaling. Since monocyte-derived DCs possess only low-cell surface levels of OX40L in the absence of CD40 signaling, OX40L was expressed by transfection of DCs with the corresponding mRNA. We show that OX40L mRNA transfection effectively enhanced the immunostimulatory function of DCs at multiple levels: OX40L mRNA transfection augmented allogeneic and HLA class II epitope-specific CD4+ T-cell responses, improved the stimulation of antigen-specific cytotoxic T lymphocytes (CTLs) in vitro without interfering with the prostaglandin E2 (PGE2)–mediated migratory function of the DCs, and facilitated interleukin 12 p70 (IL-12p70)–independent T helper type 1 (Th1) polarization of naive CD4+ T-helper cells. Furthermore, vaccination of tumor-bearing mice using OX40L mRNA–cotransfected DCs resulted in significant enhancement of therapeutic antitumor immunity due to in vivo priming of Th1-type T-cell responses. Our data suggest that transfection of DCs with OX40L mRNA may represent a promising strategy that could be applied in clinical immunotherapy protocols, while circumventing the current unavailability of reagents facilitating OX40 ligation.

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Immature dendritic cells induce alternative CD4+ T-cell responses in vivo

Transplantation Proceedings ◽

10.1016/s0041-1345(00)01993-x ◽

2001 ◽

Vol 33 (1-2) ◽

pp. 240 ◽

Cited By ~ 1

Author(s):

R.M. Suri ◽

N. Kukutsch ◽

S. Fowler ◽

F. Powrie ◽

J. Austyn

Keyword(s):

Dendritic Cells ◽

T Cell ◽

T Cell Responses ◽

Cd4 T Cell ◽

Cell Responses ◽

Immature Dendritic Cells

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Functional analysis of peripheral and intratumoral neoantigen-specific TCRs identified in a patient with melanoma

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2021-002754 ◽

2021 ◽

Vol 9 (9) ◽

pp. e002754

Author(s):

Eva Bräunlein ◽

Gaia Lupoli ◽

Franziska Füchsl ◽

Esam T Abualrous ◽

Niklas de Andrade Krätzig ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Immune Responses ◽

Immune Checkpoint ◽

T Cell Responses ◽

Functional Avidity ◽

Cell Responses

BackgroundNeoantigens derived from somatic mutations correlate with therapeutic responses mediated by treatment with immune checkpoint inhibitors. Neoantigens are therefore highly attractive targets for the development of therapeutic approaches in personalized medicine, although many aspects of their quality and associated immune responses are not yet well understood. In a case study of metastatic malignant melanoma, we aimed to perform an in-depth characterization of neoantigens and respective T-cell responses in the context of immune checkpoint modulation.MethodsThree neoantigens, which we identified either by immunopeptidomics or in silico prediction, were investigated using binding affinity analyses and structural simulations. We isolated seven T-cell receptors (TCRs) from the patient’s immune repertoire recognizing these antigens. TCRs were compared in vitro by multiparametric analyses including functional avidity, multicytokine secretion, and cross-reactivity screenings. A xenograft mouse model served to study in vivo functionality of selected TCRs. We investigated the patient’s TCR repertoire in blood and different tumor-related tissues over 3 years using TCR beta deep sequencing.ResultsSelected mutated peptide ligands with proven immunogenicity showed similar binding affinities to the human leukocyte antigen complex and comparable disparity to their wild-type counterparts in molecular dynamic simulations. Nevertheless, isolated TCRs recognizing these antigens demonstrated distinct patterns in functionality and frequency. TCRs with lower functional avidity showed at least equal antitumor immune responses in vivo. Moreover, they occurred at high frequencies and particularly demonstrated long-term persistence within tumor tissues, lymph nodes and various blood samples associated with a reduced activation pattern on primary in vitro stimulation.ConclusionsWe performed a so far unique fine characterization of neoantigen-specific T-cell responses revealing defined reactivity patterns of neoantigen-specific TCRs. Our data highlight qualitative differences of these TCRs associated with function and longevity of respective T cells. Such features need to be considered for further optimization of neoantigen targeting including adoptive T-cell therapies using TCR-transgenic T cells.

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Presentation of proteins encapsulated in sterically stabilized liposomes by dendritic cells initiates CD8+ T-cell responses in vivo

Blood ◽

10.1182/blood.v96.10.3505.h8003505_3505_3513 ◽

2000 ◽

Vol 96 (10) ◽

pp. 3505-3513 ◽

Cited By ~ 3

Author(s):

Ralf Ignatius ◽

Karsten Mahnke ◽

Miguel Rivera ◽

Keelung Hong ◽

Frank Isdell ◽

...

Keyword(s):

Dendritic Cells ◽

T Cell ◽

Soluble Protein ◽

T Cell Responses ◽

Cd8 T Cell ◽

Cd4 T Cell ◽

Cell Responses ◽

Sterically Stabilized Liposomes

Liposomes have been proposed as a vehicle to deliver proteins to antigen-presenting cells (APC), such as dendritic cells (DC), to stimulate strong T cell–mediated immune responses. Unfortunately, because of their instability in vivo and their rapid uptake by cells of the mononuclear phagocyte system on intravenous administration, most types of conventional liposomes lack clinical applicability. In contrast, sterically stabilized liposomes (SL) have increased in vivo stability. It is shown that both immature and mature DC take up SL into neutral or mildly acidic compartments distinct from endocytic vacuoles. These DC presented SL-encapsulated protein to both CD4+ and CD8+ T cells in vitro. Although CD4+ T-cell responses were comparable to those induced by soluble protein, CD8+ T-cell proliferation was up to 300-fold stronger when DC had been pulsed with SL-encapsulated ovalbumin. DC processed SL-encapsulated antigen through a TAP-dependent mechanism. Immunization of mice with SL-encapsulated ovalbumin led to antigen presentation by DC in vivo and stimulated greater CD8+ T-cell responses than immunization with soluble protein or with conventional or positively charged liposomes carrying ovalbumin. Therefore, the application of SL-encapsulated antigens offers a novel effective, safe vaccine approach if a combination of CD8+and CD4+ T-cell responses is desired (ie, in anti-viral or anti-tumor immunity).

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Correction: Peptide-Loaded Langerhans Cells, Despite Increased IL15 Secretion and T-Cell Activation In Vitro, Elicit Antitumor T-Cell Responses Comparable to Peptide-Loaded Monocyte-Derived Dendritic Cells In Vivo

Clinical Cancer Research ◽

10.1158/1078-0432.ccr-11-0931 ◽

2011 ◽

Vol 17 (11) ◽

pp. 3851-3851 ◽

Cited By ~ 1

Keyword(s):

Dendritic Cells ◽

T Cell ◽

T Cell Activation ◽

Langerhans Cells ◽

Cell Activation ◽

T Cell Responses ◽

Cell Responses

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Spatial and temporal plasticity of neoantigen-specific T-cell responses bases on characteristics associated to antigen and TCR

10.1101/2021.02.02.428777 ◽

2021 ◽

Author(s):

Eva Bräunlein ◽

Gaia Lupoli ◽

Esam T. Abualrous ◽

Niklas de Andrade Krätzig ◽

Dario Gosmann ◽

...

Keyword(s):

T Cell ◽

Immune Responses ◽

T Cell Receptors ◽

T Cell Responses ◽

Tumor Rejection ◽

Cell Receptors ◽

Cell Responses

AbstractNeoantigens derived from somatic mutations have been demonstrated to correlate with therapeutic responses mediated by treatment with immune checkpoint inhibitors. Neoantigens are therefore highly attractive targets for the development of personalized medicine approaches although their quality and associated immune responses is not yet well understood. In a case study of metastatic malignant melanoma, we performed an in-depth characterization of neoantigens and respective T-cell responses in the context of immunotherapy with Ipilimumab. Three neoantigens identified either by immunopeptidomics or in silico prediction were investigated using binding affinity analyses and structural simulations. We isolated seven T-cell receptors (TCRs) from the patient immune repertoire recognizing these antigens. TCRs were compared in-vitro and in-vivo with multi-parametric analyses. Identified immunogenic peptides showed similar binding affinities to the human leukocyte antigen (HLA) complex and comparable differences to their wildtype counterparts in molecular dynamic simulations. Nevertheless, isolated TCRs differed substantially in functionality and frequency. In fact, TCRs with comparably lower functional avidity and higher potential for cross-reactivity provided at least equal anti-tumor immune responses in vivo. Of note, these TCRs showed a reduced activation pattern upon primary in vitro stimulation. Exploration of the TCR-β repertoire in blood and in different tumor-related tissues over three years, offered insights on the high frequency and particular long-term persistence of low-avidity TCRs. These data indicate that qualitative differences of neoantigen-specific TCRs and their impact on function and longevity need to be considered for neoantigen targeting by adoptive T-cell therapy using TCR-transgenic T cells.Statement of translational relevanceImmunotherapy has demonstrated high efficacy in diverse malignancies. Neoantigens derived from mutations provide promising targets for safe and highly tumor-specific therapeutic approaches. Yet, single determinants of an effective and enduring T-cell mediated tumor rejection are still not well understood. We analyzed in detail seven neoantigen-specific T-cell receptors (TCRs) derived from a melanoma patient targeting three different altered peptide ligands identified by mass spectrometry and prediction analyses. Functional characterization of these TCRs revealed potent anti-tumor reactivity of all TCRs. Of special interest, TCRs with comparably lower affinity demonstrated effective in vivo activity as well as dominant spatial and temporal distribution in blood and tissue. Functional differences of TCR may require further T-cell and/or TCR engineering and should be considered for future clinical trial designs.

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Presentation of proteins encapsulated in sterically stabilized liposomes by dendritic cells initiates CD8+ T-cell responses in vivo

Blood ◽

10.1182/blood.v96.10.3505 ◽

2000 ◽

Vol 96 (10) ◽

pp. 3505-3513 ◽

Cited By ~ 48

Author(s):

Ralf Ignatius ◽

Karsten Mahnke ◽

Miguel Rivera ◽

Keelung Hong ◽

Frank Isdell ◽

...

Keyword(s):

Dendritic Cells ◽

T Cell ◽

Soluble Protein ◽

T Cell Responses ◽

Cd8 T Cell ◽

Cd4 T Cell ◽

Cell Responses ◽

Sterically Stabilized Liposomes

Abstract Liposomes have been proposed as a vehicle to deliver proteins to antigen-presenting cells (APC), such as dendritic cells (DC), to stimulate strong T cell–mediated immune responses. Unfortunately, because of their instability in vivo and their rapid uptake by cells of the mononuclear phagocyte system on intravenous administration, most types of conventional liposomes lack clinical applicability. In contrast, sterically stabilized liposomes (SL) have increased in vivo stability. It is shown that both immature and mature DC take up SL into neutral or mildly acidic compartments distinct from endocytic vacuoles. These DC presented SL-encapsulated protein to both CD4+ and CD8+ T cells in vitro. Although CD4+ T-cell responses were comparable to those induced by soluble protein, CD8+ T-cell proliferation was up to 300-fold stronger when DC had been pulsed with SL-encapsulated ovalbumin. DC processed SL-encapsulated antigen through a TAP-dependent mechanism. Immunization of mice with SL-encapsulated ovalbumin led to antigen presentation by DC in vivo and stimulated greater CD8+ T-cell responses than immunization with soluble protein or with conventional or positively charged liposomes carrying ovalbumin. Therefore, the application of SL-encapsulated antigens offers a novel effective, safe vaccine approach if a combination of CD8+and CD4+ T-cell responses is desired (ie, in anti-viral or anti-tumor immunity).

Download Full-text