1. |
- Eltahir, mohmo394, et al.
(author)
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Profiling of donor-specific immune effector signatures in response to rituximab in a human whole blood loop assay using blood from CLL patients
- 2021
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In: International Immunopharmacology. - : Elsevier. - 1567-5769 .- 1878-1705. ; 90
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Journal article (peer-reviewed)abstract
- Rituximab is widely used in the treatment of haematological malignancies, including chronic lymphocytic leukaemia (CLL), the most common leukaemia in adults. However, some patients, especially those with high tumour burden, develop cytokine release syndrome (CRS). It is likely that more patients will develop therapy linked CRS in the future due to the implementation of other immunotherapies, such as CAR T-cell, for many malignancies. Current methods for CRS risk assessment are limited, hence there is a need to develop new methods. To better recapitulate an in vivo setting, we implemented a unique human whole blood "loop" system to study patient-specific immune responses to rituximab in blood derived from CLL patients. Upon rituximab infusion, both complement-dependent cytotoxicity (CDC) and antibody-dependent cellular cytotoxicity (ADCC) profiles were evident in CLL patient blood, coincident with CLL cell depletion. Whereas B cell depletion is induced in healthy persons in the blood loop, only patients display B cell depletion coupled with CRS. With the exception of one donor who lacked NK cells, all other five patients displayed variable B cell depletion along with CRS profile. Additionally, inhibition of CDC or ADCC via either inhibitors or antibody Fc modification resulted in skewing of the immune killing mechanism consistent with published literature. Herein we have shown that the human whole blood loop model can be applied using blood from a specific indication to build a disease-specific CRS and immune activation profiling ex vivo system. Other therapeutic antibodies used for other indications may benefit from antibody characterization in a similar setting.
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2. |
- van Montfoort, Nadine, et al.
(author)
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Circulating specific antibodies enhance systemic cross-priming by delivery of complexed antigen to dendritic cells in vivo
- 2012
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In: European Journal of Immunology. - : Wiley. - 0014-2980 .- 1521-4141. ; 42:3, s. 598-606
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Journal article (peer-reviewed)abstract
- Increasing evidence suggests that antibodies can have stimulatory effects on T-cell immunity. However, the contribution of circulating antigen-specific antibodies on MHC class I cross-priming in vivo has not been conclusively established. Here, we defined the role of circulating antibodies in cross-presentation of antigen to CD8+ T cells. Mice with hapten-specific circulating antibodies, but naϊve for the T-cell antigen, were infused with haptenated antigen and CD8+ T-cell induction was measured. Mice with circulating hapten-specific antibodies showed significantly enhanced cross-presentation of the injected antigen compared with mice that lacked these antibodies. The enhanced cross-presentation in mice with circulating antigen-specific antibodies was associated with improved antigen capture by APCs. Importantly, CD11c+ APCs were responsible for the enhanced and sustained cross-presentation, although CD11c− APCs had initially captured a significant amount of the injected antigen. Thus, in vivo formation of antigen-antibody immune complexes improves MHC class I cross-presentation, and CD8+ T-cell activation, demonstrating that humoral immunity can aid the initiation of systemic cellular immunity. These findings have important implications for the understanding of the action of therapeutic antibodies against tumor-associated antigens intensively used in the clinic nowadays.
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3. |
- van Montfoort, Nadine, et al.
(author)
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Fcγ receptor IIb strongly regulates Fcγ receptor-facilitated T cell activation by dendritic cells
- 2012
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In: Journal of Immunology. - : The American Association of Immunologists. - 0022-1767 .- 1550-6606. ; 189:1, s. 92-101
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Journal article (peer-reviewed)abstract
- FcγR ligation by Ag-Ab immune complexes (IC) not only mediates effective Ag uptake, but also strongly initiates dendritic cell (DC) maturation, a requirement for effective T cell activation. Besides the activating FcγRI, FcγRIII, and FcγRIV, the inhibitory FcγRIIb is expressed on DCs. It is unclear how the ratio between signals from the activating FcγR and the inhibitory FcγRIIb determines the outcome of FcγR ligation on DCs. By microarray analysis, we compared the transcriptomes of steady state and IC-activated bone marrow-derived wild-type (WT) DCs expressing all FcγR or DCs expressing only activating FcγR (FcγRIIb knockout [KO]) or only the inhibitory FcγRIIb (FcR γ-chain KO). In WT DCs, we observed a gene expression profile associated with effective T cell activation, which was absent in FcR γ-chain KO, but strikingly more pronounced in FcγRIIb KO bone marrow-derived DCs. These microarray results, confirmed at the protein level for many cytokines and other immunological relevant genes, demonstrate that the transcriptome of IC-activated DCs is dependent on the presence of the activating FcγR and that the modulation of the expression of the majority of the genes was strongly regulated by FcγRIIb. Our data suggest that FcγRIIb-deficient DCs have an improved capacity to activate naive T lymphocytes. This was confirmed by their enhanced FcγR-dependent Ag presentation and in vivo induction of CD8(+) T cell expansion compared with WT DCs. Our findings underscore the potency of FcγR ligation on DCs for the effective induction of T cell immunity by ICs and the strong regulatory role of FcγRIIb.
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4. |
- Sharp, Phoebe E H, et al.
(author)
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FcγRIIb on Myeloid Cells and Intrinsic Renal Cells Rather than B Cells Protects from Nephrotoxic Nephritis
- 2013
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In: Journal of Immunology. - : The American Association of Immunologists. - 0022-1767 .- 1550-6606. ; 190:1, s. 340-348
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Journal article (peer-reviewed)abstract
- FcγRIIb is the sole inhibitory FcR for IgG in humans and mice, where it is involved in the negative regulation of Ab production and cellular activation. FcγRIIb-deficient mice show exacerbated disease following the induction of nephrotoxic nephritis (NTN). In this study, we determined the cellular origin of the FcγRIIb-knockout phenotype by inducing NTN in mice with a deficiency of FcγRIIb on either B cells alone (FcγRIIBfl/fl/CD19Cre+) or myeloid cells (FcγRIIBfl/fl/CEBPαCre+). Deletion of FcγRIIb from B cells did not increase susceptibility to NTN, compared with wild-type (WT) mice, despite higher Ab titers in the FcγRIIBfl/fl/CD19Cre+ mice compared with the WT littermate controls. In contrast, mice lacking FcγRIIb on myeloid cells had exacerbated disease as measured by increased glomerular thrombosis, glomerular crescents, albuminuria, serum urea, and glomerular neutrophil infiltration when compared with WT littermate controls. The role for FcγRIIb expression on radioresistant intrinsic renal cells in the protection from NTN was then investigated using bone marrow chimeric mice. FcγRIIb−/− mice transplanted with FcγRIIb−/− bone marrow were more susceptible to NTN than WT mice transplanted with FcγRIIb−/− bone marrow, indicating that the presence of WT intrinsic renal cells protects from NTN. These results demonstrate that FcγRIIb on myeloid cells plays a major role in protection from NTN, and therefore, augmentation of FcγRIIb on these cells could be a therapeutic target in human Ab-mediated glomerulonephritis. Where there was a lack of FcγRIIb on circulating myeloid cells, expression of FcγRIIb on intrinsic renal cells provided an additional level of protection from Ab-mediated glomerulonephritis.
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5. |
- Sharp, Phoebe E H, et al.
(author)
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Increased incidence of anti-GBM disease in Fcgamma receptor 2b deficient mice, but not mice with conditional deletion of Fcgr2b on either B cells or myeloid cells alone
- 2012
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In: Molecular Immunology. - : Elsevier BV. - 0161-5890 .- 1872-9142. ; 50:1-2, s. 49-56
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Journal article (peer-reviewed)abstract
- Fcgamma receptor 2b (Fcgr2b) is the only inhibitory Fcgamma receptor in both humans and mice, and is implicated in both antibody production and effector responses to antibody complexes. Reduced function of Fcgr2b has previously been associated with anti-glomerular basement membrane antibody (anti-GBM) disease in mice. However, the mice used had 129 genetic elements flanking the deleted Fcgr2b gene, which are known to increase susceptibility to autoimmunity. In order to confirm a role for Fcgr2b in protection from anti-GBM disease, wild type (WT) mice, mice lacking Fcgr2b on a pure C57BL/6 background, or mice lacking Fcgr2b on a C57BL/6 background with 129 flanking sequences, were immunized with the recombinant NC1 domain of alpha 3 Type IV collagen. Twenty two weeks after immunization, there was a higher incidence of crescentic glomerulonephritis, macrophage infiltration and renal dysfunction in both groups of Fcgr2b-/- mice, indicating an important role of Fcgr2b in regulating the development of anti-GBM disease, on both genetic backgrounds. In order to determine the cellular origin of the Fcgr2b-associated effect, disease was induced in mice with deficiency of Fcgr2b on either B cells alone (CD19Cre), or a subset of myeloid cells (LysozymeMCre). Neither B cell nor myeloid specific knockout mice developed crescentic glomeruonephritis with higher incidence than WT mice indicating that Fcgr2b deficiency on either B cells or a subset of myeloid cells alone is not sufficient to increase susceptibility to anti-GBM disease, but that a combination of cell types, or deficiency of Fcgr2b in a different cell type, is also required.
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6. |
- Basmo Ellingsen, Espen, et al.
(author)
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Telomerase as a Target for Therapeutic Cancer Vaccines and Considerations for Optimizing Their Clinical Potential
- 2021
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In: Frontiers in Immunology. - : Frontiers Media S.A.. - 1664-3224. ; 12
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Research review (peer-reviewed)abstract
- Telomerase-based therapeutic cancer vaccines (TCVs) have been under clinical investigation for the past two decades. Despite past failures, TCVs have gained renewed enthusiasm for their potential to improve the efficacy of checkpoint inhibition. Telomerase stands as an attractive target for TCVs due to its almost universal presence in cancer and its essential function promoting tumor growth. Herein, we review tumor telomerase biology that may affect the efficacy of therapeutic vaccination and provide insights on optimal vaccine design and treatment combinations. Tumor types possessing mechanisms of increased telomerase expression combined with an immune permissive tumor microenvironment are expected to increase the therapeutic potential of telomerase-targeting cancer vaccines. Regardless, rational treatment combinations, such as checkpoint inhibitors, are likely necessary to bring out the true clinical potential of TCVs.
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7. |
- Burman, Joachim, et al.
(author)
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T-cell responses after haematopoietic stem cell transplantation for aggressive relapsing-remitting multiple sclerosis
- 2013
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In: Immunology. - : Wiley. - 0019-2805 .- 1365-2567. ; 140:2, s. 211-219
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Journal article (peer-reviewed)abstract
- Autologous haematopoietic stem cell transplantation (HSCT) for relapsing-remitting multiple sclerosis is a potentially curative treatment, which can give rise to long-term disease remission. However, the mode of action is not yet fully understood. The aim of the study was to evaluate similarities and differences of the CD4(+) T-cell populations between HSCT-treated patients (n = 12) and healthy controls (n = 9). Phenotyping of memory T cells, regulatory T (Treg) cells and T helper type 1 (Th1) and type 17 (Th17) cells was performed. Further, T-cell reactivity to a tentative antigen, myelin oligodendrocyte glycoprotein, was investigated in these patient populations. Patients treated with natalizumab (n = 15) were included as a comparative group. White blood cells were analysed with flow cytometry and T-cell culture supernatants were analysed with magnetic bead panel immunoassays. HSCT-treated patients had similar levels of Treg cells and of Th1 and Th17 cells as healthy subjects, whereas natalizumab-treated patients had lower frequencies of Treg cells, and higher frequencies of Th1 and Th17 cells. Cells from HSCT-treated patients cultured with overlapping peptides from myelin oligodendrocyte glycoprotein produced more transforming growth factor-beta(1) than natalizumab-treated patients, which suggests a suppressive response. Conversely, T cells from natalizumab-treated patients cultured with those peptides produced more interleukin-17 (IL-17), IL-1 and IL-10, indicating a Th17 response. In conclusion, we demonstrate circumstantial evidence for the removal of autoreactive T-cell clones as well as development of tolerance after HSCT. These results parallel the long-term disease remission seen after HSCT.
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8. |
- Burman, Joachim, et al.
(author)
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The cerebrospinal fluid cytokine signature of multiple sclerosis : A homogenous response that does not conform to the Th1/Th2/Th17 convention
- 2014
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In: Journal of Neuroimmunology. - : Elsevier BV. - 0165-5728 .- 1872-8421. ; 277:1-2, s. 153-159
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Journal article (peer-reviewed)abstract
- In this cross-sectional study, we wanted to identify key cytokines characteristic of different stages of multiple sclerosis (MS). To this end, cerebrospinal fluid from patients with MS was investigated with a multiplexed fluorescent bead-based immunoassay. In total 43 cytokines were assessed and related to clinical and imaging data. Increased levels of CCL22, CXCL10 and sCD40L characterized relapsing-remitting MS patients with the presence of gadolinium-enhancing lesions; decreased CCL2 and increased CXCL1 and CCL5 were typical of relapsing-remitting MS patients irrespectively of the presence of gadolinium-enhancing lesions. These homogenous patterns of cytokine activation do not conform to conventional Th1/Th2/Th17 responses. (C) 2014 Elsevier B.V. All rights reserved.
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9. |
- Ellmark, Peter, et al.
(author)
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Kick-starting the cancer-immunity cycle by targeting CD40
- 2015
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In: Oncoimmunology. - 2162-4011 .- 2162-402X. ; 4:7
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Journal article (other academic/artistic)abstract
- Stimulation of CD40 on dendritic cells to expand and activate tumor-specific T cells and generate anticancer immunity is an attractive therapeutic approach. Since CD40 agonists exert their effects upstream of checkpoint inhibitors, including PD-1 or PD-L1 antagonists, they are ideal candidates for combination regimens.
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10. |
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11. |
- Ellmark, Peter, et al.
(author)
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Tumor-directed immunotherapy can generate tumor-specific T cell responses through localized co-stimulation
- 2017
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In: Cancer Immunology and Immunotherapy. - : Springer Science and Business Media LLC. - 0340-7004 .- 1432-0851. ; 66:1, s. 1-7
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Journal article (peer-reviewed)abstract
- The most important goals for the field of immuno-oncology are to improve the response rate and increase the number of tumor indications that respond to immunotherapy, without increasing adverse side effects. One approach to achieve these goals is to use tumor-directed immunotherapy, i.e., to focus the immune activation to the most relevant part of the immune system. This may improve anti-tumor efficacy as well as reduce immune-related adverse events. Tumor-directed immune activation can be achieved by local injections of immune modulators in the tumor area or by directing the immune modulator to the tumor using bispecific antibodies. In this review, we focus on therapies targeting checkpoint inhibitors and co-stimulatory receptors that can generate tumor-specific T cell responses through localized immune activation.
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12. |
- Eriksson, Camilla, et al.
(author)
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Epitopes displayed in a cyclic peptide scaffold bind SARS-CoV-2 antibodies
- 2023
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In: ChemBioChem. - : Wiley-VCH Verlagsgesellschaft. - 1439-4227 .- 1439-7633. ; 24:15
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Journal article (peer-reviewed)abstract
- The SARS-CoV-2 virus that causes COVID-19 is a global health issue. The spread of the virus has resulted in seven million deaths to date. The emergence of new viral strains highlights the importance of continuous surveillance of the SARS-CoV-2 virus by using timely and accurate diagnostic tools. Here, we used a stable cyclic peptide scaffolds to present antigenic sequences derived from the spike protein that are reactive to SARS-CoV-2 antibodies. Using peptide sequences from different domains of SARS-CoV-2 spike proteins, we grafted epitopes on the peptide scaffold sunflower trypsin inhibitor 1 (SFTI-1). These scaffold peptides were then used to develop an ELISA to detect SARS-CoV-2 antibodies in serum. We show that displaying epitopes on the scaffold improves reactivity overall. One of the scaffold peptides (S2_1146-1161_c) has reactivity equal to that of commercial assays, and shows diagnostic potential.
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13. |
- Eriksson, Emma, et al.
(author)
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Activation of myeloid and endothelial cells by CD40L gene therapy supports T-cell expansion and migration into the tumor microenvironment
- 2017
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In: Gene Therapy. - : Springer Science and Business Media LLC. - 0969-7128 .- 1476-5462. ; 24:2, s. 92-103
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Journal article (peer-reviewed)abstract
- CD40 is an interesting target in cancer immunotherapy due to its ability to stimulate T-helper 1 immunity via maturation of dendritic cells and to drive M2 to M1 macrophage differentiation. Pancreatic cancer has a high M2 content that has shown responsive to anti-CD40 agonist therapy and CD40 may thus be a suitable target for immune activation in these patients. In this study, a novel oncolytic adenovirus armed with a trimerized membrane-bound extracellular CD40L (TMZ-CD40L) was evaluated as a treatment of pancreatic cancer. Further, the CD40L mechanisms of action were elucidated in cancer models. The results demonstrated that the virus transferring TMZ-CD40L had oncolytic capacity in pancreatic cancer cells and could control tumor progression. TMZ-CD40L was a potent stimulator of human myeloid cells and T-cell responses. Further, CD40L-mediated stimulation increased tumor-infiltrating T cells in vivo, which may be due to a direct activation of endothelial cells to upregulate receptors for lymphocyte attachment and transmigration. In conclusion, CD40L-mediated gene therapy is an interesting concept for the treatment of tumors with high levels of M2 macrophages, such as pancreatic cancer, and an oncolytic virus as carrier of CD40L may further boost tumor killing and immune activation.
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14. |
- Eriksson, Fredrik, et al.
(author)
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Tumor-Specific Bacteriophages Induce Tumor Destruction through Activation of Tumor-Associated Macrophages
- 2009
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In: Journal of Immunology. - : The American Association of Immunologists. - 0022-1767 .- 1550-6606. ; 182:5, s. 3105-3111
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Journal article (peer-reviewed)abstract
- We recently reported that administration of tumor-specific bacteriophages initiates infiltration of neutrophilic granulocytes with subsequent regression of established B16 tumors. The aim of the current study was to investigate the mechanism of action of bacteriophage-induced tumor regression and to examine possible stimulatory effects of bacteriophages on macrophages. We observed that the mechanism of phage-induced tumor regression is TLR dependent as no signs of tumor destruction or neutrophil infiltration were observed in tumors in MyD88(-/-) mice in which TLR signaling is abolished. The microenvironment of bacteriophage-treated tumors was further analyzed by gene profiling through applying a low-density array preferentially designed to detect genes expressed by activated APCs, which demonstrated that the M2-polarized tumor microenvironment switched to a more M1-polarized milieu following phage treatment. Bacteriophage stimulation induced secretion of proinflammatory cytokines in both normal mouse macrophages and tumor-associated macrophages (TAMs) and increased expression of molecules involved in Ag presentation and costimulation. Furthermore, mouse neutrophils selectively migrated toward mediators secreted by bacteriophage-stimulated TAMs. Under these conditions, the neutrophils also exhibited increased cytotoxicity toward 1316 mouse melanoma target cells. These results describe a close interplay of the innate immune system in which bacteriophages, located to the tumor microenvironment due to their specificity, stimulate TAMs to secrete factors that promote recruitment of neutrophils and potentiate neutrophil-mediated tumor destruction.
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15. |
- Fletcher, Erika, et al.
(author)
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Formation of Immune Complexes with a Tetanus-Derived B Cell Epitope Boosts Human T Cell Responses to Covalently Linked Peptides in an Ex Vivo Blood Loop System
- 2018
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In: Journal of Immunology. - : AMER ASSOC IMMUNOLOGISTS. - 0022-1767 .- 1550-6606. ; 201:1, s. 87-97
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Journal article (peer-reviewed)abstract
- Enhancing T cell responses against both viral and tumor Ags requires efficient costimulation and directed delivery of peptide Ags into APCs. Long peptide vaccines are considered favorable vaccine moieties from a clinical perspective, as they can harbor more than one immunogenic epitope enabling treatment of a broader target population. In addition, longer peptides are not extracellularly loaded on MHC class I; rather, they require intracellular processing and will thereby be presented to T cells mainly by professional APCs, thereby avoiding the risk of tolerance induction. The drawback of peptide vaccines regardless of peptide length is that naked peptides are not actively targeted to and taken up by APCs, and the standard nonconjugated adjuvant-peptide mixtures do not ensure cotargeting of the two to the same APC. We have identified a tetanus toxin-derived B cell epitope that can mediate the formation of immune complexes in the presence of circulating Abs. In this study, we show that these immune complexes improve both Ag uptake by APCs (blood monocytes and CD1c(+) dendritic cells) and consequently improve CD8(+) T cell recall responses in a human ex vivo blood loop system. The uptake of the peptide conjugate by blood monocytes is dependent on Abs and the complement component C1q. We envision that this strategy can be used to facilitate active uptake of Ags into APCs to improve T cell responses against pathogens or cancer.
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16. |
- Ibrahim, Eman I. K., et al.
(author)
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Bridging responses to a human telomerase reverse transcriptase-based peptide cancer vaccine candidate in a mechanism-based model
- 2024
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In: International Immunopharmacology. - : Elsevier. - 1567-5769 .- 1878-1705. ; 126
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Journal article (peer-reviewed)abstract
- Therapeutic cancer vaccines are novel immuno-therapeutics, aiming to improve clinical outcomes with other immunotherapies. However, obstacles to their successful clinical development remain, which model-informed drug development approaches may address. UV1 is a telomerase based therapeutic cancer vaccine candidate being investigated in phase I clinical trials for multiple indications. We developed a mechanism-based model structure, using a nonlinear mixed‐effects modeling techniques, based on longitudinal tumor sizes (sum of the longest diameters, SLD), UV1-specific immunological assessment (stimulation index, SI) and overall survival (OS) data obtained from a UV1 phase I trial including non-small cell lung cancer (NSCLC) patients and a phase I/IIa trial including malignant melanoma (MM) patients. The final structure comprised a mechanistic tumor growth dynamics (TGD) model, a model describing the probability of observing a UV1-specific immune response (SI ≥ 3) and a time-to-event model for OS. The mechanistic TGD model accounted for the interplay between the vaccine peptides, immune system and tumor. The model-predicted UV1-specific effector CD4+ T cells induced tumor shrinkage with half-lives of 103 and 154 days in NSCLC and MM patients, respectively. The probability of observing a UV1-specific immune response was mainly driven by the model-predicted UV1-specific effector and memory CD4+ T cells. A high baseline SLD and a high relative increase from nadir were identified as main predictors for a reduced OS in NSCLC and MM patients, respectively. Our model predictions highlighted that additional maintenance doses, i.e. UV1 administration for longer periods, may result in more sustained tumor size shrinkage.
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17. |
- Irenaeus, Sandra, et al.
(author)
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Local irradiation does not enhance the effect of immunostimulatory AdCD40L gene therapy combined with low dose cyclophosphamide in melanoma patients
- 2017
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In: Oncotarget. - : Impact Journals, LLC. - 1949-2553. ; 8:45, s. 78573-78587
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Journal article (peer-reviewed)abstract
- Background: AdCD40L is an immunostimulatory gene therapy under evaluation for advanced melanoma, including ocular melanoma. Herein, we present the final data of a Phase I/IIa trial using AdCD40L alone or in combination with low dose cyclophosphamide +/- radiation therapy.Methods: AdCD40L is a replication-deficient adenovirus carrying the gene for CD40 ligand (CD40L). Twenty-four patients with advanced melanoma were enrolled and treated with AdCD40L monotherapy, or combined with cyclophosphamide +/- single fraction radiotherapy. The patients were monitored for 10 weeks using immunological and radiological evaluations and thereafter for survival.Results: AdCD40L treatment was safe and well tolerated both alone and in combination with cyclophosphamide as well as local radiotherapy. Four out of twenty-four patients had >1 year survival. Addition of cyclophosphamide was beneficial but adding radiotherapy did not further extend survival. High initial plasma levels of IL12 and MIP3b correlated to overall survival, whereas IL8 responses post-treatment correlated negatively with survival. Interestingly, antibody reactions to the virus correlated negatively with post IL6 and pre IL1b levels in blood.Conclusions: AdCD40L was safely administered to patients and effect was improved by cyclophosphamide but not by radiotherapy. Immune activation profile at baseline may predict responders better than shortly after treatment.
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18. |
- Kerzeli, Iliana K., et al.
(author)
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MALT1 inhibition suppresses antigen-specific T cell responses
- 2024
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In: Cellular Immunology. - : Elsevier. - 0008-8749 .- 1090-2163. ; 397
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Journal article (peer-reviewed)abstract
- The aim of this study was to assess the potential use of a selective small molecule MALT1 inhibitor in solid tumor treatment as an immunotherapy targeting regulatory T-cells (Tregs). In vitro, MALT1 inhibition suppressed the proteolytic cleavage of the MALT1-substrate HOIL1 and blocked IL-2 secretion in Jurkat cells. It selectively suppressed the proliferation of PBMC-derived Tregs, with no effect on conventional CD4+ T-cells. In vivo, however, no evident anti-tumor effect was achieved by MALT1 inhibition monotherapy or in combination with anti-CTLA4 in the MB49 cancer model. Despite decreased Treg-frequencies in lymph nodes of tumor-bearing animals, intratumoral Treg depletion was not observed. We also showed that MALT1-inhibition caused a reduction of antigen-specific CD8+ T-cells in an adoptive T-cell transfer model. Thus, selective targeting of Tregs would be required to improve the immunotherapeutic effect of MALT1-inhibition. Also, various dosing schedules and combination therapy strategies should be carefully designed and evaluated further.
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19. |
- Kerzeli, Iliana Kyriaki, et al.
(author)
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MALT1 inhibition suppresses T-cell dependent immune surveillance
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Other publication (other academic/artistic)abstract
- MALT1 supports the development of natural regulatory T cells (Tregs), while protease-dead MALT1 (MALT1-PD) mice develop autoimmunity and an intrinsic capacity to reject syngeneic tumor transplantation. Herein, a small molecule inhibitor targeting MALT1 was developed and evaluated for potential use in Treg inhibition as part of a cancer immunotherapy strategy.In vitro, MALT1 inhibitor treatment inhibited the proteolytic cleavage of the MALT1 substrate HOIL1 in Jurkat cells and blocked IL-2 secretion by immune cells. Moreover, orally administrated MV088428 inhibited anti-CD3 induced IL-2 release in vivo. In vitro MALT1 inhibition selectively suppressed the proliferation of PBMC derived CD25+ FoxP3+ CD4+ T cells, while no direct effect was noted on the proliferation and viability of CD25- CD4+ T cells. In vivo, no evident anti-tumor effect as a monotherapy in the MB49 bladder cancer model was achieved and despite selective decrease of Treg frequencies in lymph nodes of tumor bearing animals, intratumoral Treg depletion was not observed. No synergistic anti-tumor effects were noted when MALT1 inhibitor was combined with anti-PD1 therapy, and concomitant treatment with MALT1 inhibitor abrogated the efficacy of anti-CTLA4 therapy. MALT1 inhibition had no impact on the frequencies of viable NK, lymphocyte and myeloid cells or on proliferation of conventional CD4 and CD8 T cells. However, there was a significant decrease of antigen-specific T cells in vivo upon adoptive T cell transfer and peptide vaccination. Thus, while MALT1 inhibition substantially reduced Treg populations in lymph nodes, but less so in tumors, off-target effects on antigen-experienced T cells along with the lack of impact on tumor Tregs likely abolish the compound’s efficacy. The off-target effect on antigen-experienced T cells could present implications for the use of MALT1 inhibitors for cancer indications where tumor control is likely to be mediated via T cell driven immune surveillance. Thus, dosing length and combination therapy strategies should be carefully designed and evaluated further.
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20. |
- Kerzeli, Iliana Kyriaki, et al.
(author)
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Proximity Extension Assay reveals MMP12 in plasma as a predictor of outcome in urothelial bladder cancer
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Other publication (other academic/artistic)abstract
- Background Urothelial bladder cancer (UBC) is most-frequently diagnosed at the non-muscle-invasive stage (NMIBC). However, recurrences and interventions for intermediate and high-risk NMIBC patients impact quality of life. Biomarkers for patient stratification can help to avoid unnecessary interventions whilst indicating aggressive measures when required.Methods Proximity Extension Assay (PEA) was utilised to analyse plasma (n=90) and urine (n=40) samples from 90 newly-diagnosed and treatment-naïve UBC patients with an immuno-oncology protein panel. Public single-cell and bulk RNA sequencing data from patient tumour tissues and a murine OH-BBN induced UBC model were also explored. Results Plasma samples from muscle-invasive UBC patients displayed higher levels of MMP7 and CCL23 compared to NMIBC patients, whereas urine samples displayed higher levels of CD27 and CD40 in the NMIBC group. Increased MMP12 plasma levels were identified as an independent marker of poor survival outcome and this finding was further validated in an independent cohort. Moreover, scRNA-seq data analysis indicated tumour infiltrating macrophages as a putative source of MMP12. Conclusion The local production, but systemic diffusion of MMP12, suggests that MMP12 could be an important biomarker to complement histopathology-based risk stratification. Additionally, it may represent a pharmacological target in bladder cancer.
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21. |
- Kerzeli, Iliana Kyriaki, et al.
(author)
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The immunological landscape in bladder cancer: a single cell RNA seq analysis of tumor bearing mouse bladders with a focus on sex differences
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Other publication (other academic/artistic)abstract
- In urothelial bladder cancer differences in clinical outcomes and responses to immunotherapy associate with tumor stage and sex. However, the tumor microenvironment landscape in urothelial cancer and its contexture in different stages and sexes is not fully deciphered. We utilized an autochthonous urothelial cancer model sampled at the non-muscle and muscle invasive stage from both sexes. Single cell RNA sequencing was applied to analyze intercellular interactions and sex differences in the two stages with focus on immune cell subsets. We discerned the Cd6-Alcam interaction to occur between lymphoid, tumor and myeloid cells and that female tumor bearing bladders were enriched in cells of lymphoid lineage compared to males, although male lymphoid cells were metabolically more active. Furthermore, we identified two subsets of Macrophages, Ccl8+ and Spp1+ that were characteristic for NMIBC and MIBC respectively, however both were found to be more active in immune cell recruitment, activation and cytokine signaling in females than males. Analysis of intercellular interactions of immune cells subsets revealed the role of Lyc6c2+ and Ace+ Monocytes as antigen presenting cells equipped with co-stimulatory receptors, and the Anxa1-Fpr2 immune suppressive axis to be active among tumor cells and subsets of granulocytes, macrophages and monocytes. Collectively our results demonstrate the complexity and sex specific differences of the tumor microenvironment in urothelial cancer using a clinically relevant murine model of progressive disease, and distinguish the Cd6-Alcam and Anxa1-Fpr2 interaction pathways of lymphoid, myeloid and tumor cells as potential targets of immune modulation for cancer therapy.
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22. |
- Liljenfeldt, Lina, et al.
(author)
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CD40L gene therapy tilts the myeloid cell profile and promotes infiltration of activated T lymphocytes
- 2014
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In: Cancer Gene Therapy. - : Springer Science and Business Media LLC. - 0929-1903 .- 1476-5500. ; 21:3, s. 95-102
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Journal article (peer-reviewed)abstract
- CD40 ligand (CD40L) is a potent stimulator of tumor immunity via its activation of dendritic cells, which in turn initiate T-cell activation. However, T cells are inhibited by suppressive myeloid cells, which constitute an important part of immune evasion. We hypothesized that CD40L may revert the function of suppressive myeloid cells to generate a T-cell stimulatory environment, and this was investigated in the murine bladder cancer model MB49/C57BL/6. Upon intratumoral adenoviral CD40L (AdCD40L) gene therapy, the infiltration of CD11b(+)Gr-1(+) cells was significantly reduced, whereas activated T cells were increased. In vitro, CD40L-expressing MB49 cells tilted the myeloid subpopulations in favor of granulocytic CD11b(+)Gr-1(high) myeloid cells instead of monocytic CD11b(+)Gr-1(int/low) myeloid cells. Further, the level of macrophages in splenocyte co-cultures with MB49 cells was evaluated. In cultures with MB49 cells expressing CD40L, the overall level of macrophages was reduced and the remaining cells were differentiated into M1-like cells. Hence, these data support that CD40L tilts myeloid immune cell populations in favor of anti-tumor immunity (M1) instead of immunosuppression (CD11b(+)Gr-1(int/low) and M2), and this was accompanied by an increased level of activated T cells in the tumor tissue.
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23. |
- Lindqvist, Camilla A, et al.
(author)
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FoxP3+ T-Cells in Patients with B-Cell Chronic Lymphocytic Leukemia Express Cytolytic Markers and Kill Autologous B-Cells
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Other publication (other academic/artistic)abstract
- Recent reports indicate that infiltration of FoxP3+ cells into the tumor area may be associated with better overall survival of patients with B-cell malignancies, which is in contrast to patients with non-hematopoetic tumors. Here, we demonstrate a possible mechanism to these findings. Since the tumor cell in lymphoma originates from the immune system we hypothesized that FoxP3+ T regulatory cells (Tregs) may have a suppressive role in tumor progression in patients with B-cell malignancies. Peripheral blood was collected from 14 patients with B-cell chronic lymphocytic leukemia (B-CLL) and their Tregs were evaluated for cytolytic markers such as FasL and CD107a. We found that both conventional Tregs (CD4+ FoxP3+CD127low T-cells) and FoxP3+CD127high T-cells were significantly increased in patients with B-CLL compared to healthy controls. Further, both groups of FoxP3+ cells displayed higher expression of the degranulation marker CD107a indicating perforin/granzyme release. A flow cytometry-based cytotoxicity assay demonstrated that purified Tregs from both patients and healthy controls could kill autologous B-cells in vitro. In conclusion, FoxP3+ T-cells in patients with CLL show effector phenotype and may be involved in tumor cell control by their natural capacity to kill B-cells.
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24. |
- Lund, T., et al.
(author)
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Resolvin E1 Reduces Proinflammatory Markers in Human Pancreatic Islets in vitro
- 2010
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In: Experimental and clinical endocrinology & diabetes. - : Georg Thieme Verlag KG. - 0947-7349 .- 1439-3646. ; 118:4, s. 237-244
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Journal article (peer-reviewed)abstract
- In clinical islet transplantation, inflammatory responses initiated by the transplanted islets and by the host immune system cause acute and chronic graft loss. The resolution of acute inflammation is an active process mediated by specific signals and mediators such as resolvin E1 (RvE1). We investigated the effect of RvE1 on i) the inflammatory status of human pancreatic islets, ii) islet viability and apoptosis, and iii) the instant blood-mediated inflammatory reaction (IBMIR) in vitro. Pro-inflammatory cytokines and tissue factor (TF) in isolated human islets were determined by real-time RT-qPCR (mRNA levels), CBA and Gyrolab bioaffy (protein levels) after lipopolysaccaride (LPS) stimulation. Islet viability was measured using insulin secretion in a dynamic model, ADP/ATP ratio and total ATP content. Apoptosis was measured using commercial kits after stimulation with proinflammatory cytokines. To assess effect on IBMIR, human islets were mixed with non-anticoagulated, RvE1 or vehicle pretreated ABO-compatible blood in heparin-coated tubing loops. Treatment of human islets with RvE1 (500nM) for 24 h reduced LPS-induced increase in mRNA and protein levels of selected pro-inflammatory markers (IL-8, MCP-1, and TF). RvE1 lowered the ADP/ATP ratio, but had no effect on insulin secretion. RvE1 reduced the apoptotic effect of proinflammatory cytokines. Additionally, RvE1 reduced platelet consumption and TAT complex formation during the first 5 min after islet-blood contact. RvE1 suppresses proinflammatory markers and lowers the ADP/ATP ratio in human islets in vitro. RvE1 demonstrates antiapoptotic effects in a proinflammatory milieu. Additionally, RvE1 has modest dampening effects on IBMIR. We conclude that RvE1 may have potential in clinical islet transplantation.
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25. |
- Malmström, Per-Uno, et al.
(author)
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AdCD40L immunogene therapy for bladder carcinoma--the first phase I/IIa trial
- 2010
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In: Clinical Cancer Research. - : American Association for Cancer Research. - 1078-0432 .- 1557-3265. ; 16:12, s. 3279-3287
-
Journal article (peer-reviewed)abstract
- PURPOSE: Immunotherapy with Bacillus Calmette-Guerin (BCG) instillation is recommended for high-risk, non-muscle invasive bladder cancer. Bacillus Calmette-Guerin is not effective in advanced tumors, and better alternatives are warranted. Immunostimulating gene therapy with adenoviral vectors expressing CD40 ligand (AdCD40L) has shown efficacy in tumor models. CD40 ligand stimulates systemic immunity and may be effective in local and invasive human disease.EXPERIMENTAL DESIGN: Patients with invasive bladder cancer scheduled for cystectomy or patients with T(a) tumors were enrolled in a phase I/IIa trial. Patients were treated with three cycles of intrabladder Clorpactin WCS-90 prewash, followed by AdCD40L instillation 1 week apart. Safety, gene transfer, immune effects, and antitumor responses were monitored.RESULTS: All eight recruited patients were treated as scheduled, and therapy was well tolerated. The main adverse effect was transient local pain during prewash. Postoperatively, urinary tract infections and one case of late septicemia with elevated potassium were reported. No adverse events were ascribed to vector therapy. Gene transfer was detected in biopsies, and bladders were heavily infiltrated with T cells. The effector marker IFN-gamma increased in biopsies, whereas levels of circulating T regulatory cells were reduced. Histologic evaluation indicated that AdCD40L therapy reduced the load of malignant cells.CONCLUSIONS: To our knowledge, this is the first report on immunogene therapy in bladder cancer and the first using AdCD40L in vivo. Local AdCD40L gene therapy was safe, boosted immune activation, and should be further evaluated as a single or an adjuvant therapy for urothelial malignancies.
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26. |
- Mangsbo, Sara M, 1981-, et al.
(author)
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Complement Activation by CpG in a Human Whole Blood Loop System : Mechanisms and Immunomodulatory Effects
- 2009
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In: Journal of Immunology. - : The American Association of Immunologists, Inc.. - 0022-1767 .- 1550-6606. ; 183:10, s. 6724-6732
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Journal article (peer-reviewed)abstract
- Phosphorothioate oligodeoxynucleotides can activate complement, and experimental murine studies have revealed differential effects upon simultaneous TLR stimulation and complement activation compared with either event alone. We set out to investigate the immune stimulatory effects of CpG 2006 in fresh non-anticoagulated human blood with or without presence of active complement. We also sought to elucidate the mechanism behind complement activation upon stimulation with phosphorothioate CpG 2006. In a human blood loop system, both backbone and sequence-specific effects by CpG were counteracted by selective inhibition of C3. Furthermore, DNA backbone-mediated CD40 and CD83 expression on monocytes and sequence-specific IL-6 and TNF production were reduced by complement inhibition. CpG-induced complement activation occurred via either the classical or the alternative pathway and deposits of both IgM and properdin, two activators of complement, were detected on CpG after incubation with EDTA plasma. Quartz crystal microbalance with dissipation monitoring demonstrated alternative pathway convertase build-up onto CpG as a likely pathway to initiate and sustain complement activation. Specific inhibition of C3 suppressed CpG 2006 uptake into monocytes indicating that C3 fragments are involved in CpG internalization. The interplay between complement and TLR9 signaling demonstrated herein warrants further investigation.
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27. |
- Mangsbo, Sara M, 1981-, et al.
(author)
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CpG Therapy is Superior to BCG in an Orthotopic Bladder Cancer Model and Generates CD4+ T-cell Immunity
- 2008
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In: Journal of immunotherapy (1997). - 1524-9557 .- 1537-4513. ; 31:1, s. 34-42
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Journal article (peer-reviewed)abstract
- Bacillus Calmette Guérin (BCG) immunotherapy has been successful in extending tumor remission in bladder cancer, the fifth most common cancer in men. However, relapses are frequent and some patients develop resistance to BCG. CpGs were previously demonstrated to be effective in the murine MB49 model. In this paper, we modeled a more aggressive orthotopic bladder cancer than previously studied. Moreover, we compared standard BCG immunotherapy side-by-side with the Toll-like receptor-9 agonist CpG. MB49 tumor-bearing mice were treated with BCG or CpG and survival as well as tumor progression were observed over time. Urine, blood, and tumors were collected and analyzed. Mice were rechallenged and evaluated for tumor-specific immunity. In this study, CpGs induced a complete response of large aggressive orthotopic MB49 bladder tumors, resulting in tumor-specific systemic immunity. Further, data indicated that this potent antitumor effect required T cells. A comparison of CpGs and BCG in both a highly and less aggressive orthotopic tumor model, and in a subcutaneous tumor model, demonstrated that CpGs were superior to BCG. In the orthotopic model, BCG induced a local cytokine storm during treatment initiation whereas CpG affected a more refined cytokine pattern over time. Increased levels of cytokines in serum correlated with enhanced survival in the subcutaneous model. Further, immune cell depletion studies demonstrated that CpG-induced protective immunity was CD4 T-cell dependent. Taken together, our data suggest that CpGs are superior to BCG for bladder cancer immunotherapy. Thus, this potent new drug may be an attractive therapeutic alternative and should be evaluated in bladder cancer patients.
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28. |
- Mangsbo, Sara M, et al.
(author)
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The human agonistic CD40 antibody ADC-1013 eradicates bladder tumors and generates T cell dependent tumor immunity.
- 2015
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In: Clinical Cancer Research. - 1078-0432 .- 1557-3265. ; 21:5, s. 1115-1126
-
Journal article (peer-reviewed)abstract
- Purpose: Local administration of immune-activating antibodies may increase the efficacy and reduce the immune-related adverse events associated with systemic immunotherapy of cancer. Here we report the development and affinity maturation of a fully human agonistic CD40 antibody (IgG1), ADC-1013. Experimental Design: We have used molecular engineering to generate an agonistic antibody with high affinity for CD40. The functional activity of ADC-1013 has been investigated in human and murine in vitro models. The in vivo effect has been investigated in two separate bladder cancer models, both using human xenograft tumors in immune deficient NSG mice and using a syngeneic bladder cancer model in a novel human CD40 transgenic mouse. Results: Activation of dendritic cells (DCs) by ADC-1013 results in up-regulation of the co-stimulatory molecules CD80 and CD86, and secretion of IL-12. ADC-1013 also activates dendritic cells from human CD40 transgenic mice, and peptide-pulsed and ADC-1013-stimulated dendritic cells induce antigen-specific T cell proliferation in vitro. In vivo, treatment with ADC-1013 in a syngeneic bladder cancer model, negative for hCD40, induces significant anti-tumor effects and long-term tumor-specific immunity. Further, ADC-1013 demonstrates significant anti-tumor effects in a human bladder cancer transplanted into immunodeficient NSG mice. Conclusions: Our data demonstrate that ADC-1013 induces long-lasting anti-tumor responses and immunological memory mediated by CD40 stimulation. To the best of our knowledge, ADC-1013 represents the first immunomodulatory antibody developed for local immunotherapy of cancer.
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29. |
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30. |
- Sandin, Linda C., et al.
(author)
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Local CTLA4 blockade effectively restrains experimental pancreatic adenocarcinoma growth in vivo
- 2014
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In: Oncoimmunology. - : Informa UK Limited. - 2162-4011 .- 2162-402X. ; 3:1, s. e2761-
-
Journal article (peer-reviewed)abstract
- Antibody-mediated blockade of CTLA4 has been shown to be effective in treating a select group of patients with late-stage melanoma. The precise mechanism underlying the clinical activity of CTLA4 immunotherapy is poorly understood, although recent experimental findings indicate that antibody-mediated depletion of regulatory T cells (Tregs) in the tumor microenvironment plays a key role in efficacious antitumor responses. In the current study, we used an experimental model of pancreatic adenocarcinoma to compare the antitumor efficacy of peritumoral low-dose anti-CTLA4 monoclonal antibody (mAb) administration to that of a commonly utilized systemic high-dose anti-CTLA4 regimen. We selected pancreatic adenocarcinoma as it presents a particular challenge to clinicians due to its aggressive behavior, metastatic spread and limited treatment options. Furthermore, Fc gamma receptor (Fc gamma R)-dense myeloid cells commonly infiltrate pancreatic tumors, such that these tumor types exhibit increased susceptibility to CTLA4 antibody-targeted Treg depletion via antibody-dependent cell-mediated cytotoxicity (ADCC). Locally administered anti-CTLA4 mAb effectively reduced tumor growth at a low dose and no additional anti-tumor effects were apparent when increasing the dose or number of injections. No significant difference in overall survival was seen when comparing locally administered low-dose with standard systemic high-dose CTLA4 blockade therapy, and both delivery routes led to increased tumor-infiltrating effector T cells and reduced Treg cells. As opposed to low-dose peritumoral treatment, high-dose systemic therapy stimulated the accumulation of Tregs in secondary lymphoid organs, an effect that could potentially counteract the antitumor immunotherapeutic benefit of CTLA4 blockade. Our study confirms previous findings that local administration of low-dose anti-CTLA4 antibody generates sustained antitumor effects and provides rationale to devise ultrasound-guided intratumoral anti-CTLA4 antibody injection regimens to treat patients with pancreatic adenocarcinoma and other types of solid tumors. In support, clinical relevancy could include reduced immune-related adverse events by limiting systemic antibody spread to immune cell-dense organs.
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31. |
- Sandin, Linda C., et al.
(author)
-
Local immunotherapy based on agonistic CD40 antibodies effectively inhibits experimental bladder cancer
- 2014
-
In: Oncoimmunology. - : Informa UK Limited. - 2162-4011 .- 2162-402X. ; 3:2
-
Journal article (other academic/artistic)abstract
- Local immunotherapy resurfaces in the field of cancer as a potential way to cure localized and metastatic disease with limited toxic effects. We have recently demonstrated that local administration of agonistic CD40 antibodies can cure localized as well as disseminated bladder neoplasms. This approach reduces the circulating concentrations of antibodies that would result from systemic delivery, hence resulting in limited toxicity.
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32. |
- van Hooren, Luuk, et al.
(author)
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Agonistic CD40 therapy induces tertiary lymphoid structures but impairs responses to checkpoint blockade in glioma.
- 2021
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In: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 12:1
-
Journal article (peer-reviewed)abstract
- Gliomas are brain tumors characterized by an immunosuppressive microenvironment. Immunostimulatory agonistic CD40 antibodies (αCD40) are in clinical development for solid tumors, but are yet to be evaluated for glioma. Here, we demonstrate that systemic delivery of αCD40 in preclinical glioma models induces the formation of tertiary lymphoid structures (TLS) in proximity of meningeal tissue. In treatment-naïve glioma patients, the presence of TLS correlates with increased T cell infiltration. However, systemic delivery of αCD40 induces hypofunctional T cells and impairs the response to immune checkpoint inhibitors in pre-clinical glioma models. This is associated with a systemic induction of suppressive CD11b+ B cells post-αCD40 treatment, which accumulate in the tumor microenvironment. Our work unveils the pleiotropic effects of αCD40 therapy in glioma and reveals that immunotherapies can modulate TLS formation in the brain, opening up for future opportunities to regulate the immune response.
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33. |
- van Hooren, Luuk, et al.
(author)
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Sunitinib enhances the antitumor responses of agonistic CD40-antibody by reducing MDSCs and synergistically improving endothelial activation and T-cell recruitment
- 2016
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In: Oncotarget. - : Impact Journals, LLC. - 1949-2553. ; 7:31, s. 50277-50289
-
Journal article (peer-reviewed)abstract
- CD40-activating immunotherapy has potent antitumor effects due to its ability to activate dendritic cells and induce cytotoxic T-cell responses. However, its efficacy is limited by immunosuppressive cells in the tumor and by endothelial anergy inhibiting recruitment of T-cells. Here, we show that combining agonistic CD40 monoclonal antibody (mAb) therapy with vascular targeting using the tyrosine kinase inhibitor sunitinib decreased tumor growth and improved survival in B16.F10 melanoma and T241 fibrosarcoma. Treatment of tumor-bearing mice with anti-CD40 mAb led to increased activation of CD11c(+) dendritic cells in the tumor draining lymph node, while sunitinib treatment reduced vessel density and decreased accumulation of CD11b(+)Gr1(+) myeloid derived suppressor cells. The expression of ICAM-1 and VCAM-1 adhesion molecules was up-regulated on tumor endothelial cells only when anti-CD40 mAb treatment was combined with sunitinib. This was associated with enhanced intratumoral infiltration of CD8(+) cytotoxic T-cells. Our results show that combining CD40-stimulating immunotherapy with sunitinib treatment exerts potent complementary antitumor effects mediated by dendritic cell activation, a reduction in myeloid derived suppressor cells and increased endothelial activation, resulting in enhanced recruitment of cytotoxic T-cells.
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34. |
- Vogel, Stephanie, et al.
(author)
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Antibody induced CD4 down-modulation of T cells is site-specifically mediated by CD64(+) cells
- 2015
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In: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 5
-
Journal article (peer-reviewed)abstract
- Treatment of PBMC with the CD4-specific mAb BT-061 induces CD4 down-modulation of T cells. Here we report that addition of BT-061 to purified T cells did not confer this effect, whereas incubation of T cells in BT-061 coated wells restored CD4 down-modulation. These results implied that Fc gamma receptor mediated cell-cell interactions played a role. In consistence with this hypothesis PBMC depleted of CD64(+) monocytes did not confer CD4 down-modulation of BT-061 decorated T cells. Strikingly, CD4 down-modulation was observed in BT-061 treated synovial fluid punctuated from patients' inflamed joints that comprised enhanced numbers of CD64(+) cells. In contrast, in a circulating whole blood system injection of BT-061 did not induce CD4 down-modulation, due to CD64 saturation by serum IgG. Similarly, tonsil derived mononuclear cells devoid of CD64(+) cells did not show CD4 down-modulation, whereas addition of blood derived monocytes restored the effect. Thus, the interaction of BT-061 decorated T cells with CD64(+) cells is needed for CD4 down-modulation, implying that in patients BT-061 would primarily induce CD4 down-modulation at inflammatory sites. These results highlight the need not only to examine the interaction of a given mAb with single Fc gamma R, but also the immunological environment that is appropriate to support such interactions.
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35. |
- Yilmaz-Elis, A Seda, et al.
(author)
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FcγRIIb on myeloid cells rather than on B cells protects from collagen-induced arthritis
- 2014
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In: Journal of Immunology. - : The American Association of Immunologists. - 0022-1767 .- 1550-6606. ; 192:12, s. 5540-5547
-
Journal article (peer-reviewed)abstract
- Extensive analysis of a variety of arthritis models in germline KO mice has revealed that all four receptors for the Fc part of IgG (FcγR) play a role in the disease process. However, their precise cell type-specific contribution is still unclear. In this study, we analyzed the specific role of the inhibiting FcγRIIb on B lymphocytes (using CD19Cre mice) and in the myeloid cell compartment (using C/EBPαCre mice) in the development of arthritis induced by immunization with either bovine or chicken collagen type II. Despite their comparable anti-mouse collagen autoantibody titers, full FcγRIIb knockout (KO), but not B cell-specific FcγRIIb KO, mice showed a significantly increased incidence and severity of disease compared with wild-type control mice when immunized with bovine collagen. When immunized with chicken collagen, disease incidence was significantly increased in pan-myeloid and full FcγRIIb KO mice, but not in B cell-specific KO mice, whereas disease severity was only significantly increased in full FcγRIIb KO mice compared with incidence and severity in wild-type control mice. We conclude that, although anti-mouse collagen autoantibodies are a prerequisite for the development of collagen-induced arthritis, their presence is insufficient for disease development. FcγRIIb on myeloid effector cells, as a modulator of the threshold for downstream Ab effector pathways, plays a dominant role in the susceptibility to collagen-induced arthritis, whereas FcγRIIb on B cells, as a regulator of Ab production, has a minor effect on disease susceptibility.
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