scholarly journals Selective tumor antigen vaccine delivery to human CD169+antigen-presenting cells using ganglioside-liposomes

2020 ◽  
Vol 117 (44) ◽  
pp. 27528-27539
Author(s):  
Alsya J. Affandi ◽  
Joanna Grabowska ◽  
Katarzyna Olesek ◽  
Miguel Lopez Venegas ◽  
Arnaud Barbaria ◽  
...  
Keyword(s):  
T Cells ◽  
Tumor Antigen ◽  
Tumor Antigens ◽  
Ex Vivo ◽  
Antigen Presenting Cells ◽  
Dependent Manner ◽  
Cross Presentation ◽  
Vaccine Carrier ◽  
Antigen Presenting

Priming of CD8+T cells by dendritic cells (DCs) is crucial for the generation of effective antitumor immune responses. Here, we describe a liposomal vaccine carrier that delivers tumor antigens to human CD169/Siglec-1+antigen-presenting cells using gangliosides as targeting ligands. Ganglioside-liposomes specifically bound to CD169 and were internalized by in vitro-generated monocyte-derived DCs (moDCs) and macrophages and by ex vivo-isolated splenic macrophages in a CD169-dependent manner. In blood, high-dimensional reduction analysis revealed that ganglioside-liposomes specifically targeted CD14+CD169+monocytes and Axl+CD169+DCs. Liposomal codelivery of tumor antigen and Toll-like receptor ligand to CD169+moDCs and Axl+CD169+DCs led to cytokine production and robust cross-presentation and activation of tumor antigen-specific CD8+T cells. Finally, Axl+CD169+DCs were present in cancer patients and efficiently captured ganglioside-liposomes. Our findings demonstrate a nanovaccine platform targeting CD169+DCs to drive antitumor T cell responses.

scholarly journals IMMU-41. RNA-MODIFIED T CELLS AS PROFESSIONAL ANTIGEN PRESENTING CELLS

2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi127-vi128
Author(s):  
Fernanda Pohl-Guimarães ◽  
Duane Mitchell
Keyword(s):  
T Cells ◽  
Tumor Antigen ◽  
Messenger Rna ◽  
Cellular Proliferation ◽  
Tumor Antigens ◽  
Genetically Modified ◽  
Antigen Presenting Cells ◽  
Activated T Cells ◽  
Antigen Presenting

Abstract INTRODUCTION With the lack of antigen presenting cells (APCs) in the central nervous system (CNS), anti-tumor immune responses from intracranial tumors are believed to be initiated in the peripheral lymph nodes. Recently, studies have shown that intratumoral dendritic cells (DCs), a well-known professional APC, play a crucial role at inducing anti-tumor immunity. Although DCs have been tested in cancer immunotherapy clinical trials for two decades, DC delivery strategies have limited access to the CNS, mainly due to the blood brain barrier (BBB). To bypass the limitations of the lack of intracranial APCs, we investigate the HYPOTHESIS that RNA-modified T cells can express and cross-present single tumor antigens locally within the CNS tumor microenvironment. Since activated T cells have an inherent ability to cross the BBB and can be genetically modified, this strategy makes them an attractive professional antigen presenting cells for cancer cell therapy. METHODS Using electroporation to deliver messenger RNA (mRNA) encoding a model tumor antigen to T cells, we evaluated the expression and cross-presentation capability of RNA-modified T cells. RESULTS We demonstrated that activated T cells can be genetically modified to express tumor antigens in vitro while retaining their inherent effector functions. Compared to unmodified T cells, T cells modified with tumor antigen encoding RNA showed high expression of inflammatory cytokines, including IFN gamma and TNF alpha and enhanced cellular proliferation and IL-2 secretion. Tumor antigen RNA-modified T cells demonstrated potent antigen presentation in vitro and importantly were significantly superior to RNA-loaded DCs in antigen presenting capacity. CONCLUSIONS This study strongly supports the implementation of a non-invasive and efficacious strategy to deliver “APC-like” T cell locally to brain tumors, thereby bypassing the lack of APCs within CNS malignancies.

scholarly journals 751 Neo-X-Prime bispecific antibodies targeting CD40 and tumor antigens promote cross-presentation of tumor exosome-derived neoantigen and induce superior anti-tumor responses compared to CD40 mAb

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A785-A785
Author(s):  
Karin Hagerbrand ◽  
Mattias Levin ◽  
Laura Von Schantz ◽  
Laura Varas ◽  
Anna Säll ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Tumor Antigens ◽  
Antigen Presenting Cells ◽  
Immunological Memory ◽  
Cell Repertoire ◽  
Cross Presentation ◽  
Antigen Presenting

BackgroundAlligator's Neo-X-Prime platform aims to enable antigen presenting cells to efficiently enhance priming of tumor neoantigen-specific T cells with the goal of overcoming PD-1 resistance in certain tumor types. We hypothesize that binding of a CD40 x TAA bispecific antibody (bsAb) to CD40 on dendritic cells (DCs) and a tumor-associated antigen (TAA) on tumor exosomes or tumor debris leads to (i) activation of the DC, (ii) uptake of the tumor material, (iii) cross-presentation of tumor-derived neoantigen (present in exosomes or debris) and, iv) priming of tumor neoantigen-specific T cells, resulting in an increased quantity and/or quality of the tumor-targeting T cell pool.MethodsFunctionality was evaluated in vitro using CD40 reporter cells and monocyte-derived DCs, co-cultured with cells expressing TAA. Further, co-localization of TAA-expressing cellular debris with a CD40-expressing human B cell line in the presence of bsAbs was assessed using live cell imaging. In vivo, anti-tumor efficacy and immunological memory were assessed in human CD40 transgenic (hCD40tg) mice bearing MB49 bladder carcinoma tumors transfected with human TAA or controls. T cells isolated from OVA-specific TCR-transgenic mice were used to evaluate the effect of Neo-X-Prime bsAbs on antigen-specific T cell expansion in the presence of hCD40tg DCs and exosomes from MB49 tumors transfected with both human TAA and OVA using flow cytometry.ResultsUsing CEA as a highly expressed TAA, we have developed lead Neo-X-Prime CD40-CEA bsAbs engineered to achieve an optimal profile. Further, using Neo-X-Prime concept molecules targeting EpCAM, we have demonstrated the ability to mediate co-localization of tumor debris and CD40 expressing antigen presenting cells that is dependent on the receptor density of the TAA. We have further shown that addition of Neo-X-Prime bsAbs to a co-culture of murine DCs, T cells and tumor-derived exosomes induces increased expansion of model neoantigen-specific T cells. In vivo, Neo-X-Prime bsAbs display a potent, TAA-dependent anti-tumor effect that is superior to CD40 mAbs. Cured mice develop a broad immunological memory that is not dependent on expression of the TAA. The tumor-localizing property of Neo-X-Prime bsAbs also shows potential for improved safety compared to CD40 monospecific antibodies.ConclusionsNeo-X-Prime bsAbs have the potential to tumor-selectively target CD40-expressing antigen-presenting cells to mediate an expansion of the tumor-specific T cell repertoire, resulting in increased T cell infiltration and potent anti-tumor effects.Ethics ApprovalAll experiments were performed after approval from the Malmö/Lund Animal Ethics Committee.

Treatment of intracranial gliomas with bone marrow—derived dendritic cells pulsed with tumor antigens

1999 ◽  
Vol 90 (6) ◽  
pp. 1115-1124 ◽  
Author(s):  
Linda M. Liau ◽  
Keith L. Black ◽  
Robert M. Prins ◽  
Steven N. Sykes ◽  
Pier-Luigi DiPatre ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Dendritic Cells ◽  
Tumor Antigen ◽  
Tumor Antigens ◽  
Antigen Presenting Cells ◽  
Content Type ◽  
Cytotoxicity Assays ◽  
Antigen Presenting ◽  
Fine Print

Object. An approach toward the treatment of intracranial gliomas was developed in a rat experimental model. The authors investigated the ability of “professional” antigen-presenting cells (dendritic cells) to enhance host antitumor immune responses when injected as a vaccine into tumor-bearing animals.Methods. Dendritic cells, the most potent antigen-presenting cells in the body, were isolated from rat bone marrow precursors stimulated in vitro with granulocyte—macrophage colony-stimulating factor (GM-CSF) and interleukin-4. Cultured cell populations were confirmed to be functional antigen-presenting cells on the basis of expressed major histocompatibility molecules, as analyzed by fluorescence-activated cell sorter cytofluorography. These dendritic cells were then pulsed (cocultured) ex vivo with acid-eluted tumor antigens from 9L glioma cells. Thirty-eight adult female Fischer 344 rats harboring 7-day-old intracranial 9L tumors were treated with three weekly subcutaneous injections of either control media (10 animals), unpulsed dendritic cells (six animals), dendritic cells pulsed with peptides extracted from normal rat astrocytes (10 animals), or 9L tumor antigen—pulsed dendritic cells (12 animals). The animals were followed for survival. At necropsy, the rat brains were removed and examined histologically, and spleens were harvested for cell-mediated cytotoxicity assays.The results indicate that tumor peptide-pulsed dendritic cell therapy led to prolonged survival in rats with established intracranial 9L tumors implanted 7 days prior to the initiation of vaccine therapy in vivo. Immunohistochemical analyses were used to document a significantly increased perilesional and intratumoral infiltration of CD8+ and CD4+ T cells in the groups treated with tumor antigen—pulsed dendritic cells compared with the control groups. In addition, the results of in vitro cytotoxicity assays suggest that vaccination with these peptide-pulsed dendritic cells can induce specific cytotoxic T lymphocytes against 9L tumor cells.Conclusions. Based on these results, dendritic antigen-presenting cells pulsed with acid-eluted peptides derived from autologous tumors represent a promising approach to the immunotherapy of established intracranial gliomas, which may serve as a basis for designing clinical trials in patients with brain tumors.

Efficient Binding, but Moderate Modulation, of Human Dendritic Cell Functions by Milatuzumab, a Humanized Anti-CD74 Monoclonal Antibody

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 2649-2649 ◽  
Author(s):  
Xiaochuan Chen ◽  
Chien-Hsing Chang ◽  
David Goldenberg
Keyword(s):  
Monoclonal Antibody ◽  
T Cells ◽  
Cell Viability ◽  
Antigen Presenting Cells ◽  
Lymphocytic Leukemia ◽  
Dependent Manner ◽  
Immune Functions ◽  
Cell Functions ◽  
Antigen Presenting

Abstract Milatuzumab (hLL1, Immunomedics, Inc.), a humanized anti-CD74 immunoglobulin-G monoclonal antibody (MAb), has been shown to have therapeutic activity against CD74-expressing B-cell malignancies in vitro and in xenografts models, and is in clinical evaluation as a therapeutic MAb for non-Hodgkin lymphoma, chronic lymphocytic leukemia, and multiple myeloma. Since it is unclear whether this MAb has any effects on human antigen-presenting cells that express CD74, we investigated the binding efficiency, viability, and functional modulation of human dendritic cells (DC), the professional and most potent antigen-presenting cells, exposed to milatuzumab. We found that milatuzumab bound efficiently with B cells, monocytes, and different subsets of blood DCs including myeloid DC1 (BDCA-1+), myeloid DC2 (BDCA-3+) and plasmacytoid DC (BDCA-2+) in human PBMC, as well as with monocyte-derived immature DCs, but not LPS-matured DCs. The side-by-side comparative cytotoxicity assay showed that milatuzumab, in the presence of a second antibody for cross-linking (GAH, the F(ab′)2 of goat anti-human IgG Fcgamma-specific), dramatically reduced the cell viability of Daudi B-lymphoma cells, but did not influence the cell viability or induce apoptosis in monocyte-derived DCs, even at high concentations up to 50 μg/ml. At the concentrations ranging from 0.05 to 5 μg/ml, milatuzumab upregulated the expression of the antigen-presenting molecule, HLA-DR, and costimulatory molecules, CD54 and CD86, in human monocyte-derived DCs in a moderate, but dose-dependent manner, suggesting that milatuzumab could enhance DC constitutive maturation. Although this effect was not reflected by an enhanced T-cell expansion, as shown by unaltered CFSE-low, -medium, and –high peaks in total and CD4+ and CD4− T cells, milatuzumab-treated DCs could moderately promote the differentiation of CD4+ naïve T cells toward more Th1 effector cells, suggesting that milatuzumab can modulate DC functions, inducing the polarization and differentiation of functional Th cells. These data highlight the prospects of milatuzumab as a novel immunotherapeutic agent that possesses not only direct anti-proliferative effects against CD74+ hematological malignancies, but also some regulatory effects on DC-mediated immune functions, and no cytotoxic effect on DCs.

scholarly journals Complete responses of relapsed lymphoma following genetic modification of tumor-antigen presenting cells and T-lymphocyte transfer

Blood ◽  
2007 ◽  
Vol 110 (8) ◽  
pp. 2838-2845 ◽  
Author(s):  
Catherine M. Bollard ◽  
Stephen Gottschalk ◽  
Ann M. Leen ◽  
Heidi Weiss ◽  
Karin C. Straathof ◽  
...  
Keyword(s):  
T Cells ◽  
Genetic Modification ◽  
Tumor Antigens ◽  
Ex Vivo ◽  
Antigen Presenting Cells ◽  
Bulky Disease ◽  
Barr Virus ◽  
Relapsed Disease ◽  
Antigen Presenting

AbstractEpstein-Barr virus (EBV)–associated tumors developing in immunocompetent individuals present a challenge to immunotherapy, since they lack expression of immunodominant viral antigens. However, the tumors consistently express viral proteins including LMP2, which are immunologically “weak” but may nonetheless be targets for immune T cells. We previously showed that a majority of cytotoxic T lymphocytes (CTLs) reactivated using EBV-transformed B-lymphoblastoid cells lines (LCLs) contained minor populations of LMP2-specific T cells and homed to tumor sites. However, they did not produce remissions in patients with bulky disease. We have now used gene transfer into antigen-presenting cells (APCs) to augment the expression and immunogenicity of LMP2. These modified APCs increased the frequency of LMP2-specific CTLs by up to 100-fold compared with unmodified LCL-APCs. The LMP2-specific population expanded and persisted in vivo without adverse effects. Nine of 10 patients treated in remission of high-risk disease remain in remission, and 5 of 6 patients with active relapsed disease had a tumor response, which was complete in 4 and sustained for more than 9 months. It is therefore possible to generate immune responses to weak tumor antigens by ex vivo genetic modification of APCs and the CTLs so produced can have substantial antitumor activity. This study is registered at http://www.cancer.gov/clinicaltrials (protocol IDs: BCM-H-9936, NCT00062868, NCT00070226).

scholarly journals Development of Stable Chimeric IL-15 for Trans-Presentation by the Antigen Presenting Cells

2021 ◽  
Vol 12 ◽  
Author(s):  
Manoj Patidar ◽  
Naveen Yadav ◽  
Sarat K. Dalai
Keyword(s):  
T Cells ◽  
T Cell ◽  
Half Life ◽  
Therapeutic Potential ◽  
Chimeric Protein ◽  
Antigen Presenting Cells ◽  
T Cell Response ◽  
Antigen Presenting

IL-15 is one of the important biologics considered for vaccine adjuvant and treatment of cancer. However, a short half-life and poor bioavailability limit its therapeutic potential. Herein, we have structured IL-15 into a chimeric protein to improve its half-life enabling greater bioavailability for longer periods. We have covalently linked IL-15 with IgG2 base to make the IL-15 a stable chimeric protein, which also increased its serum half-life by 40 fold. The dimeric structure of this kind of IgG based biologics has greater stability, resistance to proteolytic cleavage, and less frequent dosing schedule with minimum dosage for achieving the desired response compared to that of their monomeric forms. The structured chimeric IL-15 naturally forms a dimer, and retains its affinity for binding to its receptor, IL-15Rβ. Moreover, with the focused action of the structured chimeric IL-15, antigen-presenting cells (APC) would transpresent chimeric IL-15 along with antigen to the T cell, that will help the generation of quantitatively and qualitatively better antigen-specific memory T cells. In vitro and in vivo studies demonstrate the biological activity of chimeric IL-15 with respect to its ability to induce IL-15 signaling and modulating CD8+ T cell response in favor of memory generation. Thus, a longer half-life, dimeric nature, and anticipated focused transpresentation by APCs to the T cells will make chimeric IL-15 a super-agonist for memory CD8+ T cell responses.

scholarly journals Scaffolds that mimic antigen-presenting cells enable ex vivo expansion of primary T cells

2018 ◽  
Vol 36 (2) ◽  
pp. 160-169 ◽  
Author(s):  
Alexander S Cheung ◽  
David K Y Zhang ◽  
Sandeep T Koshy ◽  
David J Mooney
Keyword(s):  
T Cells ◽  
Ex Vivo ◽  
Antigen Presenting Cells ◽  
Ex Vivo Expansion ◽  
Antigen Presenting

scholarly journals Inhibition of two-pore channels in antigen-presenting cells promotes the expansion of TNFR2-expressing CD4+Foxp3+ regulatory T cells

2020 ◽  
Vol 6 (40) ◽  
pp. eaba6584
Author(s):  
Tianzhen He ◽  
De Yang ◽  
Xiao-Qing Li ◽  
Mengmeng Jiang ◽  
Md Sahidul Islam ◽  
...  
Keyword(s):  
T Cells ◽  
Regulatory T Cells ◽  
Inflammatory Responses ◽  
Therapeutic Potential ◽  
Inflammatory Diseases ◽  
Antigen Presenting Cells ◽  
Surface Expression ◽  
Pore Channel ◽  
Dependent Manner ◽  
Antigen Presenting

CD4+Foxp3+ regulatory T cells (Tregs) are pivotal for the inhibition of autoimmune inflammatory responses. One way to therapeutically harness the immunosuppressive actions of Tregs is to stimulate the proliferative expansion of TNFR2-expressing CD4+Foxp3+ Tregs via transmembrane TNF (tmTNF). Here, we report that two-pore channel (TPC) inhibitors markedly enhance tmTNF expression on antigen-presenting cells. Furthermore, injection of TPC inhibitors including tetrandrine, or TPC-specific siRNAs in mice, increases the number of Tregs in a tmTNF/TNFR2-dependent manner. In a mouse colitis model, inhibition of TPCs by tetrandrine markedly attenuates colon inflammation by expansion of Tregs. Mechanistically, we show that TPC inhibitors enhance tmTNF levels by disrupting surface expression of TNF-α–converting enzyme by regulating vesicle trafficking. These results suggest that the therapeutic potential of TPC inhibitors is mediated by expansion of TNFR2-expressing Tregs and elucidate the basis of clinical use in the treatment of autoimmune and other inflammatory diseases.

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