We have performed whole genome expression arrays covering over 47000 transcripts comparing the transcriptional profile of NKp80+ to NKp80- CD8+ CCR7- alpha beta T cells. A highly similar global gene expression profile was observed between both memory phenotype T cell subsets. Interestingly, the majority of differentially expressed genes are immune-associated. NKp80+ cells contained markedly increased levels of transcripts encoding for MHC class I and II molecules and for numerous members of the KIR family. Also other NK-related transcripts were more abundantly expressed in the NKp80+ subset. With regards to cytokines, chemokines and their receptors, transcripts important for homeostasis and proliferation are expressed differently. Also transcripts encoding for adhesion molecules are present at different levels in both T cell subsets. Further cytotoxic effector molecules are expressed differently.
NKp80 defines and stimulates a reactive subset of CD8 T cells.
Sex, Specimen part
View SamplesThe TAP transporter is responsible for transferring cytosolic peptides into the ER where they can be loaded onto MHC molecules. Deletion of TAP results in a drastic reduction of MHC surface expression and alters the presented peptide pattern. Using the TAP deficient cell line LCL721.174 and its TAP expressing progenitor cell line LCL721.45, we have identified and quantified more than 160 HLA ligands, 50 out of which were presented TAP independently. Peptides which were predominantly presented on the TAP deficient LCL721.174 cell line had a decreased MHC binding affinity according to their SYFPEITHI and BIMAS score. About half of the identified TAP independently presented peptides were not derived from signal sequences and may partly be generated by the proteasome. Furthermore, we have excluded that different HLA presentation ratios were due to varying expression of the respective protein or due to changes in the antigen loading complex. Features of TAP-independently presented peptides as well as proteasomal contribution to their generation provides an insight into basic immunological mechanisms.
Features of TAP-independent MHC class I ligands revealed by quantitative mass spectrometry.
No sample metadata fields
View SamplesThe vascular endothelial growth factor A (VEGF) is involved in various physiological processes such as angiogenesis or wound healing but is also crucial in pathological events such as tumor growth. Thus, clinical anti-VEGF treatments have been developed which could already prove to have enormous beneficial effects for cancer patients. In this article we describe the first VEGF-derived CD8+ T-cell epitope. The natural HLA ligand SRFGGAVVR was identified by differential mass spectrometry in two primary renal cell carcinomas (RCC) and was significantly over-presented on both tumor tissues. SRFGGAVVR is derived from a cryptic translated region of VEGF presumably by initiation of translation at the non-classical start codon CUG499. SRFGGAVVR specific T-cells were generated in vitro using peptide loaded dendritic cells or artificial antigen presenting cells. They were identified by HLA tetramer analysis after in vitro stimulation. SRFGGAVVR specific CD8+ T-cells were fully functional T-effector cells, which were able to secrete IFN-gamma upon stimulation and killed tumor cells in vitro. Additionally, we have quantitatively analyzed VEGF mRNA and protein levels in RCC tumor and normal tissue samples by gene chip analysis, qRT-PCR, in situ hybridization, and bead based immuno assay. In the future, T-cells directed against VEGF as a tumor associated antigen may represent a possible way of combining peptide-based anti-VEGF immunotherapy with already existent anti-VEGF cancer therapies.
A cryptic vascular endothelial growth factor T-cell epitope: identification and characterization by mass spectrometry and T-cell assays.
No sample metadata fields
View SamplesIn recent years, several approaches have been taken in the peptide-based immunotherapy of metastatic renal cell carcinoma (RCC), although little is known about HLA presentation on metastases compared to primary tumor and normal tissue of RCC. In this study we compared primary tumor, normal tissue and metastases with the aim of identifying similarities and differences between these tissues. We performed this comparison for two RCC patients on the level of the HLA ligandome using mass spectrometry and for three patients on the level of the transcriptome using oligonucleotide microarrays. The quantitative results show that primary tumor is more similar to metastasis than to normal tissue, both on the level of HLA ligand presentation and mRNA. We were able to characterize a total of 142 peptides in the qualitative analysis of HLA-presented peptides. Six of them were significantly overpresented on metastasis, among them a peptide derived from CD151; fourteen were overpresented on both primary tumor and metastasis compared to normal tissue, among them an HLA ligand derived from tumor protein p53. Thus, we could demonstrate that peptide-based immunotherapy might affect tumor as well as metastasis of RCC, but not healthy kidney tissue. Furthermore we were able to identify several peptides derived from tumor-associated antigens that are suitable for vaccination of metastatic RCC.
HLA ligand profiles of primary renal cell carcinoma maintained in metastases.
Sex
View SamplesThe synergistic regimen CT-VT-RT triggers proinflammatory antiviral signalling with activation of apoptotic cascades resulting in tumor cell death. Overall design: The experiment was designed to elicit individual treatment effects using monotherapies to understand the combinatorial sequential effect of dual and triple regimen using appropriate controls.
Measles Virus-Based Treatments Trigger a Pro-inflammatory Cascade and a Distinctive Immunopeptidome in Glioblastoma.
Specimen part, Cell line, Treatment, Subject, Time
View SamplesAssessment of mRNA expression changes in the B-lymphoblastoid cell line Awells after 6 h and 24 h of starvation-induced autophagy
Autophagy promotes MHC class II presentation of peptides from intracellular source proteins.
No sample metadata fields
View SamplesChronic lymphocytic leukemia (CLL) is a disorder of mature B cells. Most patients are characterized by indolent disease and an anergic phenotype of their leukemia cells which refers to a state of unresponsiveness to B cell receptor stimulation. Using the E-TCL1 mouse model, we show that B cell-specific ablation of NFAT2 leads to the loss of the anergic phenotype culminating in a significantly compromised life expectancy and histological transformation to aggressive disease. We further define a gene expression signature of anergic CLL cells consisting of several NFAT2-dependant genes employing microarray technology.
NFAT2 is a critical regulator of the anergic phenotype in chronic lymphocytic leukaemia.
Age, Specimen part
View SamplesCytotoxic T-lymphocyte associated antigen-4 (CTLA-4) and Programmed death-1 (PD-1) are immunoregulatory receptors expressed on T cells that play important roles in suppressing immune responses to cancer. Although monoclonal antibodies that target CTLA-4 or PD-1 stimulate therapeutic anti-tumour T cell responses, the tumour antigens recognized by checkpoint blockade immunotherapy remain undefined. Herein, we use genomics and bioinformatics approaches to identify tumour-specific mutant proteins as a major class of T cell rejection antigens following aPD-1 and/or aCTLA-4 treatment of mice bearing progressively growing sarcomas. We validate this conclusion by showing that (a) the predicted mutant epitopes associate with MHC class I molecules of the tumour; (b) T cells specific for these mutant epitopes infiltrate tumours; and (c) therapeutic vaccines incorporating these mutant epitopes induce tumour rejection comparably to checkpoint blockade immunotherapy. Whereas, T cells with the same antigen specificity are present in progressively growing tumours in control mice, tumour-specific T cells in aPD-1- and/or aCTLA-4-treated mice express some overlapping but mostly treatment-specific transcriptional profiles that render them capable of tumour rejection. Thus, tumour-specific mutant antigens are not only important targets of checkpoint blockade therapy but also can be used to identify tumour antigen-specific T cells that function as biomarkers of successful anti-tumour responses. Overall design: For sorting of mLama4-specific cells, tumour-infiltrating cells were enriched for CD45+ cells using CD45 cell purification magnetic beads (Miltenyi Biotec). CD45 enriched cells were then sorted gating for PI- CD3e+ CD8a+ mLama4-tetramer-PE+ or PI- CD3e+ CD8a+ mLama4-tetramer-PE- cells. Sorting was performed on a BD FACSAria II (BD Biosciences). Sorted cells were pelleted and processed for RNA analysis. All flow cytometry was performed on the FACSCalibur (BD Biosciences) or LSR Fortessa (BD Biosciences) and analysed using FlowJo software (TreeStar).
Checkpoint blockade cancer immunotherapy targets tumour-specific mutant antigens.
No sample metadata fields
View SamplesObjective: Dyslipidemia is one of the key factors behind coronary heart disease. Blood and lymphatic vessels play pivotal roles in both lipoprotein metabolism and development of atherosclerotic plaques. Recent studies have linked members of Vascular Endothelial Growth Factor (VEGF) family to lipid metabolism but the function of VEGF-D has remained unexplored. Here we investigated how the deletion of VEGF-D affects lipid and lipoprotein metabolism in atherogenic LDLR-/-ApoB100/100 mice. Approach and Results: Deletion of VEGF-D (Vegfd-/-LDLR-/-ApoB100/100) led to markedly elevated plasma cholesterol and triglyceride levels without an increase in atherogenesis. Size distribution and hepatic lipid uptake studies confirmed a delayed clearance of large chylomicron remnant particles that cannot easily penetrate through the vascular endothelium. Mechanistically, the inhibition of VEGF-D signaling significantly decreased the hepatic expression of syndecan 1 (SDC1), which is one of the main receptors for chylomicron remnant uptake when LDLR is absent. Immunohistochemical staining confirmed reduced expression of SDC1 in the sinusoidal surface of hepatocytes in VEGF-D deficient mice. Furthermore, hepatic RNA sequencing revealed that VEGF-D is also an important regulator of genes related to lipid metabolism and inflammation. The lack of VEGF-D signaling via VEGF receptor 3 led to lowered expression of genes regulating triglyceride and cholesterol production as well as downregulation of peroxisomal ß-oxidation pathway. Conclusions: These results demonstrate that VEGF-D, a powerful lymphangiogenic and angiogenic growth factor, is also a major regulator of chylomicron metabolism in mice. Overall design: Gene expression profiling of mouse liver tissue from control and VEGF-D knock-out mice. Control and VEGF-D KO mice were both in C57Bl/6 and atherosclerotic background, i.e., deficient of LDLR and expressing only apolipoprotein B100.
Deletion of Lymphangiogenic and Angiogenic Growth Factor VEGF-D Leads to Severe Hyperlipidemia and Delayed Clearance of Chylomicron Remnants.
Specimen part, Cell line, Subject
View SamplesThe transcription factor STAT1 is essential for interferon- (IFN) mediated protective immunity in humans and mice. Two splice isoforms of STAT1, STAT1 and STAT1, differ with regard to a C-terminal transactivation domain, which is absent in STAT1. Dimers of STAT1 are therefore considered transcriptionally inactive and potential competitive inhibitors of STAT1. Contrasting this view, generation and analysis of mice deficient for either STAT1 or STAT1 demonstrated transcriptional activity of the STAT1 isoform and its enhancement of innate immunity. Gene expression profiling in primary cells revealed overlapping, but also non-redundant and gene-specific activities of STAT1 and STAT1 in response to IFN. Consistently, both isoforms mediated protective, IFN-dependent immunity against the bacterium Listeria monocytogenes, although with remarkably different efficiency. In contrast, STAT1 and STAT1 were largely redundant for transcriptional responses to IFN/ and for IFN/-dependent antiviral activity. Collectively, our data shed new light on how STAT1 isoforms contribute to antimicrobial immunity.
STAT1β is not dominant negative and is capable of contributing to gamma interferon-dependent innate immunity.
Specimen part
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