| 1. |
- Campbell, Diahnn, et al.
(författare)
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Enhanced anti-tumor immune responses and delay of tumor development in human epidermal growth factor receptor 2 mice immunized with an immunostimulatory peptide in poly(D, L-lactic-co-glycolic) acid nanoparticles nanoparticles
- 2015
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Ingår i: Breast Cancer Research. - : BioMed Central. - 1465-5411 .- 1465-542X. ; 17:48
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Tidskriftsartikel (refereegranskat)abstract
- Introduction Cancer vaccines have the potential to induce curative anti-tumor immune responses and better adjuvants may improve vaccine efficacy. We have previously shown that Hp91, a peptide derived from the B box domain in high-mobility group box protein 1 (HMGB1), acts as potent immune adjuvant. Method In this study, Hp91 was tested as part of a therapeutic vaccine against human epidermal growth factor receptor 2 (HER2) positive breast cancer. Results Free peptide did not significantly augment immune responses but, when delivered in poly(D, L-lactic-co-glycolic) acid nanoparticles (PLGA-NPs), robust activation of dendritic cells (DCs) and increased activation of HER2 specific T cells was observed in vitro. Vaccination of HER2NEU transgenic mice, a mouse breast cancer model that closely mimics the immune modulation and tolerance in some breast cancer patients, with Hp91 loaded PLGA-NPs enhanced the activation of HER2 specific cytotoxic T lymphocyte (CTL) responses, delayed tumor development, and prolonged survival. Conclusion Taken together these findings demonstrate that the delivery of the immunostimulatory peptide Hp91 inside PLGA-NPs enhances the potency of the peptide and efficacy of a breast cancer vaccine.
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| 2. |
- Saenz, Rebecca, et al.
(författare)
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TLR4-dependent activation of dendritic cells by an HMGB1-derived peptide adjuvant
- 2014
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Ingår i: Journal of Translational Medicine. - : BioMed Central. - 1479-5876. ; 12:211
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Tidskriftsartikel (refereegranskat)abstract
- High mobility group box protein 1 (HMGB1) acts as an endogenous danger molecule that is released from necrotic cells and activated macrophages. We have previously shown that peptide Hp91, whose sequence corresponds to an area within the B-Box domain of HMGB1, activates dendritic cells (DCs) and acts as an adjuvant in vivo. Here we investigated the underlying mechanisms of Hp91-mediated DC activation. Hp91-induced secretion of IL-6 was dependent on clathrin-and dynamin-driven endocytosis of Hp91 and mediated through a MyD88- and TLR4-dependent pathway involving p38 MAPK and NF kappa B. Endosomal TLR4 has been shown to activate the MyD88-independent interferon pathway. Hp91-induced activation of pIRF3 and IL-6 secretion was reduced in IFN alpha beta R knockout DCs, suggesting an amplification loop via the IFN alpha beta R. These findings elucidate the mechanisms by which Hp91 acts as immunostimulatory peptide and may serve as a guide for the future development of synthetic Th1-type peptide adjuvants for vaccines.
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| 3. |
- Che, Karlhans Fru, et al.
(författare)
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Cross Talk between P38MAPK and STAT3 Regulates Expression of Negative Costimulatory Molecules and Transcriptional Repressors in HIV-1 Primed T cells
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- HIV-1 infection enhances the expression of negative costimulatory molecules on T cellsleading to T cell impairment. The signaling pathway underlying the regulation ofinhibitory molecules and the subsequent onset of T cell impairment remains to beinvestigated. Herein, we showed that the T cells activated by HIV-pulsed dendritic cells(DCs) upregulated CTLA-4, TRAIL, LAG-3, TIM-3, and CD160 and suppressionassociated transcription factors BLIMP-1, DTX1, and FOXP3, leading to T cellsuppression. The induction of suppressor T cells was regulated by the signal transducerand activator of transcription 3 (STAT3) molecules as blockade of this pathwaysignificantly down regulates the expression of inhibitory molecules. The cytokines IL-6and IL-10 were not responsible for STAT3 activation as their neutralization could neitherrecover T cell proliferation nor decrease the expression of negative costimulatorymolecules. Contrarily, we demonstrated that the intracytoplasmic cross-talk of P38Mitogen-Activated Protein Kinase (MAPK) with STAT3 was responsible as blockade ofthe P38MAPK significantly impaired negative costimulatory molecular expression andthe subsequent recovery of T cell proliferation. Notably, the blockade of viral access toDC cytosol, via CD4 binding and fusion, significantly reduced the negative effects DCsimposed on the primed T cells. In conclusion, viral access to cytosol modulated theDCs- T cell priming to induce T cells with upreguled expression of negativecostimulatory molecules in a P38MAPK/STAT3 pathway dependent fashion
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| 4. |
- Che, Karlhans Fru, et al.
(författare)
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p38 Mitogen-Activated Protein Kinase/Signal Transducer and Activator of Transcription-3 Pathway Signaling Regulates Expression of Inhibitory Molecules in T Cells Activated by HIV-1-Exposed Dendritic Cells
- 2012
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Ingår i: Molecular Medicine. - : Feinstein Institute for Medical Research. - 1076-1551 .- 1528-3658. ; 18:8, s. 1169-1182
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Tidskriftsartikel (refereegranskat)abstract
- Human immunodeficiency virus type 1 (HIV-1) infection enhances the expression of inhibitory molecules on T cells, leading to T-cell impairment. The signaling pathways underlying the regulation of inhibitory molecules and subsequent onset of T-cell impairment remain elusive. We showed that both autologous and allogeneic T cells exposed to HIV-pulsed dendritic cells (DCs) upregulated cytotoxic T-lymphocyte antigen (CTLA-4), tumor-necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), lymphocyte-activation gene-3 (LAG3). T-cell immunoglobulin mucin-3 (TIM-3), CD160 and certain suppression-associated transcription factors, such as B-lymphocyte induced maturation protein-1 (BLIMP-1), deltex homolog 1 protein (DTX1) and forkhead box P3 (FOXP3), leading to T-cell suppression. This induction was regulated by p38 mitogen-activated protein kinase/signal transducer and activator of transcription-3 (P38MAPK/STAT3) pathways, because their blockade significantly abrogated expression of all the inhibitory molecules studied and a subsequent recovery in T-cell proliferation. Neither interleukin-6 (IL-6) nor IL-10 nor growth factors known to activate STAT3 signaling events were responsible for STAT3 activation. Involvement of the P38MAPK/STAT3 pathways was evident because these proteins had a higher level of phosphorylation in the HIV-1-primed cells. Furthermore, blockade of viral CD4 binding and fusion significantly reduced the negative effects DCs imposed on primed T cells. In conclusion, HIV-1 interaction with DCs modulated their functionality, causing them to trigger the activation of the P38MAPK/STAT3 pathway in T cells, which was responsible for the upregulation of inhibitory molecules. Online address: http://www.molmed.org doi: 10.2119/molmed.2012.00103
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| 5. |
- Clawson, Corbin, et al.
(författare)
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Delivery of a peptide via poly(D,L-lactic-co-glycolic) acid nanoparticles enhances its dendritic cell-stimulatory capacity
- 2010
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Ingår i: NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE. - : Future Medicine. - 1549-9634. ; 6:5, s. 651-661
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Tidskriftsartikel (refereegranskat)abstract
- Nanoparticles (NPs) are attractive carriers for vaccines. We have previously shown that a short peptide (Hp91) activates dendritic cells (DCs), which are critical for initiation of immune responses. In an effort to develop Hp91 as a vaccine adjuvant with NP carriers, we evaluated its activity when encapsulated in or conjugated to the surface of poly(D, L-lactic-co-glycolic) acid (PLGA) NPs. We found that Hp91, when encapsulated in or conjugated to the surface of PLGA-NPs, not only activates both human and mouse DCs, but is in fact more potent than free Hp91. Hp91 packaged within NPs was about fivefold more potent than the free peptide, and Hp91 conjugated to the surface of NPs was similar to 20-fold more potent than free Hp91. Because of their capacity to activate DCs, such NP-Hp91 systems are promising as delivery vehicles for subunit vaccines against infectious disease or cancer.
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| 6. |
- Futalan, Diahnn, et al.
(författare)
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Effect of Oxygen Levels on the Physiology of Dendritic Cells: Implications for Adoptive Cell Therapy
- 2011
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Ingår i: Molecular Medicine. - : Feinstein Institute for Medical Research. - 1076-1551 .- 1528-3658. ; 17:9-10, s. 910-916
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Tidskriftsartikel (refereegranskat)abstract
- Dendritic cell (DC)-based adoptive tumor immunotherapy approaches have shown promising results, but the incidence of tumor regression is low and there is an evident call for identifying culture conditions that produce DCs with a more potent Th1 potential. Routinely, DCs are differentiated in CO(2) incubators under atmospheric oxygen conditions (21% O(2)), which differ from physiological oxygen levels of only 3-5% in tissue, where most DCs reside. We investigated whether differentiation and maturation of DCs under physiological oxygen levels could produce more potent T-cell stimulatory DCs for use in adoptive immunotherapy. We found that immature DCs differentiated under physiological oxygen levels showed a small but significant reduction in their endocytic capacity. The different oxygen levels did not influence their stimuli-induced upregulation of cluster of differentiation 54 (CD54), CD40, CD83, CD86, C-C chemokine receptor type 7 (CCR7), C-X-C chemokine receptor type 4 (CXCR4) and human leukocyte antigen (HLA)-DR or the secretion of interleukin (IL)-6, tumor necrosis factor (TNF)-alpha and IL-10 in response to lipopolysaccharide (LPS) or a cytokine cocktail. However. DCs differentiated under physiological oxygen level secreted higher levels of IL-12(p70) after exposure to LPS or CD40 ligand. Immature DCs differentiated at physiological oxygen levels caused increased T-cell proliferation, but no differences were observed for mature DCs with regard to T-cell activation. In conclusion, we show that although DCs generated under atmospheric or physiological oxygen conditions are mostly similar in function and phenotype, DCs differentiated under physiological oxygen secrete larger amounts of IL-12(p70). This result could have implications for the use of ex vivo-generated DCs for clinical studies, since DCs differentiated at physiological oxygen could induce increased Th1 responses in vivo.
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| 7. |
- Tjomsland, Vegard, et al.
(författare)
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IL-1α Expression in Pancreatic Ductal Adenocarcinoma Affects the Tumor Cell Migration and Is Regulated by the p38MAPK Signaling Pathway
- 2013
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Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 8:8
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Tidskriftsartikel (refereegranskat)abstract
- The interplay between the tumor cells and the surrounding stroma creates inflammation, which promotes tumor growth and spread. The inflammation is a hallmark for pancreatic adenocarcinoma (PDAC) and is to high extent driven by IL-1α. IL-1α is expressed and secreted by the tumor cells and exerting its effect on the stroma, i.e. cancer associated fibroblasts (CAF), which in turn produce massive amount of inflammatory and immune regulatory factors. IL-1 induces activation of transcription factors such as nuclear factor-κβ (NF-κβ), but also activator protein 1 (AP-1) via the small G-protein Ras. Dysregulation of Ras pathways are common in cancer as this oncogene is the most frequently mutated in many cancers. In contrast, the signaling events leading up to the expression of IL-1α by tumor cells are not well elucidated. Our aim was to examine the signaling cascade involved in the induction of IL-1α expression in PDAC. We found p38MAPK, activated by the K-Ras signaling pathway, to be involved in the expression of IL-1α by PDAC as blocking this pathway decreased both the gene and protein expression of IL-1α. Blockage of the P38MAPK signaling in PDAC also dampened the ability of the tumor cell to induce inflammation in CAFs. In addition, the IL-1α autocrine signaling regulated the migratory capacity of PDAC cells. Taken together, the blockage of signaling pathways leading to IL-1α expression and/or neutralization of IL-1α in the PDAC microenvironment should be taken into consideration as possible treatment or complement to existing treatment of this cancer.
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| 8. |
- Tjomsland, Vegard, et al.
(författare)
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IL-1α Sustains the Inflammation in Human Pancreatic Cancer Microenvironment by Targeting Cancer Associated Fibroblasts
- 2010
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The tumor microenvironment in pancreatic ductal adenocarcinoma (PDAC) is dynamic with an extensive interaction between the stroma and tumor cells. Our aim for this study was to delineate the cross-talk between PDAC and cancer-associated fibroblasts (CAFs) with focus on the mechanism creating the chronic inflammatory tumor milieu. We assessed the effect cross talk between primary PDAC and CAF cell lines propagated from tumors had on the creation and sustenance of an inflammatory environment and what factors that were involved in establishing the inflammation. The coculture of PDAC and CAF cell lines, propagated from tumor tissues, enhanced the levels of inflammatory factors including IL-1α, IL-6, CXCL8, VEGFA, CCL20, and COX-2. The production of these factors correlated with the expression detected in vivo in PDAC tissues. The key producers of nearly all inflammatory factors were the CAFs and not the tumor cells. IL-1α was produced by the tumor cell lines, whereas almost all IL-1RI was expressed by CAFs thus corresponding to their in vivo expression profile in PDAC tissues, indicating a role for the IL-1 signaling cascade in a tumor favorable microenvironment. Neutralization of the IL-1α pathway efficiently diminished the cross talk induced production of inflammatory factors, both in stroma and tumor cells. These data suggest that the cross-talk between PDAC cells and the main stroma cell type, i.e. CAFs, is one contributing factor in the formation of the inflammatory tumor environment and we propose that the neutralization of IL-1α pathway might be a potential therapy for this cancer.
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| 9. |
- Tjomsland, Vegard, 1978-, et al.
(författare)
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Interleukin 1α sustains the expression of inflammatory factors in human pancreatic cancer microenvironment by targeting cancer-associated fibroblasts
- 2011
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Ingår i: Neoplasia. - : Neoplasia Press. - 1522-8002 .- 1476-5586. ; 13:8, s. 664-675
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Tidskriftsartikel (refereegranskat)abstract
- The tumor microenvironment in pancreatic ductal adenocarcinoma (PDAC) is dynamic with an extensive interaction between the stroma and tumor cells. The aim for this study was to delineate the cross-talk between PDAC and cancer-associated fibroblasts (CAFs) with focus on the mechanism creating the chronic inflammatory tumor milieu. We assessed the effects of the cross-talk between primary PDAC and CAF cell lines on the creation and sustenance of the inflammatory tumor microenvironment in pancreatic cancer. The coculture of primary PDAC and CAF cell lines enhanced the levels of inflammatory factors including IL-1á, IL-6, CXCL8, VEGFA, CCL20, and COX-2. CAFs were superior to tumor cells regarding the production of most inflammatory factors and tumor cell associated IL-1á was established as the initiator of the enhanced production of inflammatory factors through the binding of IL-1á to the active IL-1 receptor (IL-1R1) expressed predominantly by CAFs. Furthermore, we found a positive correlation between IL-1á and CXCL8 expression levels in PDAC tissues and correlation between IL-1á expression and the clinical outcome of the patients. This confirmed an important role for the IL-1 signaling cascade in the creation and sustenance of a tumor favorable microenvironment. Neutralization of the IL-1á signaling efficiently diminished the cross-talk induced production of inflammatory factors. These data suggest that the cross-talk between PDAC cells and the main stroma cell type, i.e. CAFs, is one essential factor in the formation of the inflammatory tumor environment and we propose that neutralization of the IL-1á signaling might be a potential therapy for this cancer.
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| 10. |
- Tjomsland, Vegard, et al.
(författare)
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Pancreatic adenocarcinoma exerts systemic effects on the peripheral blood myeloid and plasmacytoid dendritic cells: an indicator of disease severity?
- 2010
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Ingår i: BMC CANCER. - : BioMed Central. - 1471-2407. ; 10:87
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Tidskriftsartikel (refereegranskat)abstract
- Background: Dendritic cells (DCs) isolated from tumor bearing animals or from individuals with solid tumors display functional abnormalities and the DC impairment has emerged as one mechanism for tumor evasion from the control of the immune system. Ductal pancreatic adenocarcinoma (PDAC), the most common pancreatic cancer, is recognized as a very aggressive cancer type with a mortality that almost matches the rate of incidence. Methods: We examined the systemic influence ductal pancreatic adenocarcinoma ( PDAC) exerted on levels of peripheral blood DCs and inflammatory mediators in comparison to the effects exerted by other pancreatic tumors, chronic pancreatitis, and age-matched controls. Results: All groups examined, including PDAC, had decreased levels of myeloid DCs (MDC) and plasmacytoid DCs (PDC) and enhanced apoptosis in these cells as compared to controls. We found elevated levels of PGE2 and CXCL8 in subjects with PDAC, and chronic pancreatitis. Levels of these inflammatory factors were in part restored in PDAC after tumor resection, whereas the levels of DCs were impaired in the majority of these patients similar to 12 weeks after tumor removal. Our results prove that solid pancreatic tumors, including PDAC, systemically affect blood DCs. The impairments do not seem to be tumor-specific, since similar results were obtained in subjects with chronic pancreatitis. Furthermore, we found that PDAC patients with a survival over 2 years had significant higher levels of blood DCs compared to patients with less than one year survival. Conclusions: Our findings points to the involvement of inflammation in the destruction of the blood MDCs and PDCs. Furthermore, the preservation of the blood DCs compartment in PDAC patients seems to benefit their ability to control the disease and survival.
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| 11. |
- Tjomsland, Vegard, et al.
(författare)
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Pancreatic cancer microenvironment has a high degree of inflammation and infiltrating immune cells in its stroma
- 2010
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Tumor microenvironment is composed of tumor cells, fibroblasts, and infiltrating immune cells, and other cellular components, which work together and create an inflammatory environment favoring tumor progression. The present study aimed to characterize the expression and location of immune cells and investigate inflammatory factors that influence pancreatic ductal adenocarcinoma (PDAC). Methods: qPCRs and immunohistological stainings were performed for inflammatory factors and immune cells localized in tumor tissues from patients with PDAC (N=30). Results: All PDAC tissues had significant increased levels of inflammatory and chemotactic factors such as IL-1α, COX-2, CXCL8, CCL2, and CCL20 as compared to controls. The PDAC stroma, i.e. the fibrosis surrounding the tumor, was the main producer of these factors with the exception of IL-1α, which was expressed by tumor cells and some infiltrating immune cells. The gene expression for immune cell specific markers CD163, CD1c, CD303, and CD8, corresponding to macrophages, myeloid dendritic cells (DCs), plasmacytoid DCs, and cytotoxic T lymphocytes (CTL), respectively, were all significantly increased in PDAC tissues. Immunostaining of the tumor tissue confirmed the elevated levels of infiltrating macrophages, DCs, mature DCs, and cytotoxic T lymphocytes (CTL). The different immune cells were in nearly all cases localized in the fibrotic tissue adjacent to tumor nests. Production of CXCL8 mRNA and protein by the stroma was dependent on the tumor expression of IL-1α. Of importance, we found a correlation in expression of the proinflammatory factor IL-1α and the PDAC patients’ survival time. Conclusion: PDAC cells seem to take advantage of IL-1α to create an inflammatory microenvironment with high degree of fibrosis and the ability to both recruit and activate immune cells and the level of inflammation in this environment influenced the clinical outcome for the patients. Therapies targeting the inflammation might be beneficial for the survival of patients with PDAC.
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| 12. |
- Tjomsland, Vegard, et al.
(författare)
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Semi Mature Blood Dendritic Cells Exist in Patients with Ductal Pancreatic Adenocarcinoma Owing to Inflammatory Factors Released from the Tumor
- 2010
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 5:10
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Tidskriftsartikel (refereegranskat)abstract
- Background: Much evidence exists regarding the fact that blood DCs, both myeloid DCs (MDCs) and plasmacytoid DCs (PDCs), are negatively affected in different types of cancer, with both reduced numbers and impaired functionality. Functional impairment of DCs in patients with pancreatic ductal adenocarcinoma (PDAC), may contribute to the poor clinical outcome. The aim of this study was to examine the effects PDAC had on blood DCs and elucidate the underlying mechanism responsible for the DC impairment. Methodology/Principal Findings: We examined the systemic influence PDAC exerted on blood DCs by ex vivo measuring numerous activation and maturation markers expressed on these cells. Furthermore, the effect patient plasma and the inflammatory factors CXCL8 and PGE(2) had on purified MDCs and PDCs from healthy donors was assessed and compared to the DCs existing in PDAC patients. We found a partial maturation of the blood MDCs and PDCs in PDAC patients with significantly enhanced expression of CD83, CD40, B7H3, PDL-1, CCR6, and CCR7 and decreased expression of ICOSL, and DCIR. These changes lead to impairment in their immunostimulatory function. Furthermore, chronic pancreatitis gave rise to DCs with similar semi-mature phenotype as seen in PDAC. Low expression of ICOSL was associated with poor prognosis. We found that the mechanism underlying this semi-maturation of DCs was inflammatory factors existing in the PDAC patients plasma. Of note, PGE2, which is elevated PDAC patient plasma, was one contributing factor to the changes seen in MDCs and PDCs phenotype. Conclusion/Significance: Our findings point to a role for the systemic inflammation in transforming blood MDCs and PDCs into semi-mature cells in PDAC patients and we show a correlation between maturation status and clinical outcome. Thus, means to preserve a functional blood DC compartment in PDAC patients by diminishing the inflammation could facilitate their ability to control the disease and improve survival.
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| 13. |
- Tjomsland, Vegard, et al.
(författare)
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The Desmoplastic Stroma Plays an Essential Role in the Accumulation and Modulation of Infiltrated Immune Cells in Pancreatic Adenocarcinoma
- 2011
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Ingår i: Clinical & Developmental Immunology. - : Hindawi Publishing Corporation. - 1740-2522 .- 1740-2530. ; 2011:212810
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Tidskriftsartikel (refereegranskat)abstract
- Tumor microenvironment is composed of tumor cells, fibroblasts, and infiltrating immune cells, which all work together and create an inflammatory environment favoring tumor progression. The present study aimed to investigate the role of the desmoplastic stroma in pancreatic ductal adenocarcinoma (PDAC) regarding expression of inflammatory factors and infiltration of immune cells and their impact on the clinical outcome. The PDAC tissues examined expressed significantly increased levels of immunomodulatory and chemotactic factors (IL-6, TGF beta, IDO, COX-2, CCL2, and CCL20) and immune cell-specific markers corresponding to macrophages, myeloid, and plasmacytoid dendritic cells (DCs) as compared to controls. Furthermore, short-time survivors had the lowest levels of DC markers. Immunostainings indicated that the different immune cells and inflammatory factors are mainly localized to the desmoplastic stroma. Therapies modulating the inflammatory tumor microenvironment to promote the attraction of DCs and differentiation of monocytes into functional DCs might improve the survival of PDAC patients.
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