Search results for "TAP1"

showing 6 items of 6 documents

Defects in the Human Leukocyte Antigen Class I Antigen Processing Machinery in Head and Neck Squamous Cell Carcinoma: Association with Clinical Outco…

2005

AbstractPurpose: Human leukocyte antigen (HLA) class I antigen defects, which are frequently present in head and neck squamous cell carcinoma (HNSCC) cells may provide the tumor with an escape mechanism from immune surveillance. Scanty information is available about mechanisms underlying HLA class I antigen defects in both lesions and cell lines from HNSCC. In this study, we investigate the role of antigen processing machinery (APM) component abnormalities in the generation of deficient HLA class I surface expression of HNSCC cells.Experimental Design: Using immunohistochemistry, Western blot, and RT-PCR analyses we correlated the expression of the IFN-γ inducible proteasome subunits and of…

AdultMaleProteasome Endopeptidase ComplexCancer ResearchPathologymedicine.medical_specialtyBlotting WesternDown-RegulationHuman leukocyte antigenBiologyCell LineInterferon-gammaATP Binding Cassette Transporter Subfamily B Member 3HLA AntigensMultienzyme ComplexesCell Line TumorTumor Cells Culturedotorhinolaryngologic diseasesmedicineCarcinomaHumansATP Binding Cassette Transporter Subfamily B Member 2AgedReverse Transcriptase Polymerase Chain ReactionAntigen processingHistocompatibility Antigens Class ICancerMiddle Agedmedicine.diseaseImmunohistochemistrySurvival AnalysisHead and neck squamous-cell carcinomaGene Expression Regulation NeoplasticCysteine Endopeptidasesstomatognathic diseasesOncologyHead and Neck NeoplasmsCarcinoma Squamous Cellbiology.proteinImmunohistochemistryTAP2ATP-Binding Cassette TransportersFemaleTAP1Clinical Cancer Research
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Deficient expression of components of the MHC class I antigen processing machinery in human cervical carcinoma.

2001

In cervical carcinomas abnormalities in the MHC class I surface expression are a frequent event, which are often associated with the deficient expression of the peptide transporter subunit TAP1 thereby resulting in impaired T cell response. In order to understand the role of other components of the MHC class I antigen processing machinery (APM) in the immune escape, 16 surgically removed primary cervical carcinoma lesions were analyzed for their mRNA expression of the heterodimeric peptide transporter TAP, the constitutive and interferon (IFN)-gamma inducible proteasome subunits and their activators PA28alpha/beta, various chaperones as well as MHC class I antigens. High expression levels o…

Cancer ResearchAntigen presentationBlotting WesternDown-RegulationGene ExpressionGenes MHC Class IUterine Cervical NeoplasmsHuman leukocyte antigenBiologyInterferon-gammaInterferonMHC class ImedicineBiomarkers TumorTumor Cells CulturedHumansRNA MessengerCells CulturedDNA PrimersAntigen PresentationAntigen processingMHC class I antigenReverse Transcriptase Polymerase Chain ReactionHistocompatibility Antigens Class ITransporter associated with antigen processingNeoplasm ProteinsPhenotypeOncologyImmunologyCancer researchbiology.proteinFemaleTAP1medicine.drugInternational journal of oncology
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High frequency of a non-functional TAP1/LMP2 promoter polymorphism in human tumors

2002

The Tap1 and Tap2 genes encoding for a heterodimeric peptide transporter play a key role in antigen processing and presentation. The TAP complex mediates the transport of peptides generated by the IFN-gamma-inducible proteasome subunits LMP2, 7 and 10 from the cytosol into the endoplasmic reticulum (ER), where they bind to MHC class I molecules. In contrast to the frequent polymorphisms within the rat Tap genes which exert functional differences, polymorphic regions within the human Tap genes have been demonstrated, but not systematically analyzed in terms of their functional significance. Both the Tap1 and Lmp2 genes are transcribed from a bidirectional intergenic promoter which is regulat…

Cancer ResearchTransfectionViral Matrix ProteinsIntergenic regionGene FrequencyGenotypeMHC class ITumor Cells CulturedAnimalsHumansRNA MessengerATP Binding Cassette Transporter Subfamily B Member 2Promoter Regions GeneticCarcinoma Renal CellMelanomaGeneGeneticsPolymorphism GeneticbiologyReverse Transcriptase Polymerase Chain ReactionAntigen processingEndoplasmic reticulumMolecular biologyGene Expression Regulation NeoplasticOncologyCOS Cellsbiology.proteinTAP2ATP-Binding Cassette TransportersTAP1International Journal of Oncology
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Impaired Transporter Associated with Antigen Processing (TAP) Function Attributable to a Single Amino Acid Alteration in the Peptide TAP Subunit TAP1

2003

Abstract The heterodimeric peptide transporter TAP belongs to the ABC transporter family. Sequence comparisons with the P-glycoprotein and cystic fibrosis transmembrane conductance regulator and the functional properties of selective amino acids in these ABC transporters postulated that the glutamic acid at position 263 and the phenylalanine at position 265 of the TAP1 subunit could affect peptide transporter function. To define the role of both amino acids, TAP1 mutants containing a deletion or a substitution to alanine at position 263 or 265 were generated and stably expressed in murine and human TAP1−/− cells. The different TAP1 mutants were characterized in terms of expression and funct…

Cytotoxicity ImmunologicMacromolecular SubstancesPhenylalanineImmunologyAntigen presentationGlutamic AcidATP-binding cassette transporterEndoplasmic ReticulumTransfectionCell LineMiceAdenosine TriphosphateATP Binding Cassette Transporter Subfamily B Member 3MHC class IAnimalsHumansImmunology and AllergyATP Binding Cassette Transporter Subfamily B Member 2Sequence DeletionAlaninechemistry.chemical_classificationAntigen PresentationbiologyHistocompatibility Antigens Class I3T3 CellsIntracellular MembranesTransporter associated with antigen processingMolecular biologyPeptide FragmentsCystic fibrosis transmembrane conductance regulatorAmino acidMice Inbred C57BLProtein SubunitsAmino Acid SubstitutionBiochemistrychemistryMutagenesis Site-Directedbiology.proteinATP-Binding Cassette TransportersTAP1Sequence AlignmentProtein BindingT-Lymphocytes CytotoxicThe Journal of Immunology
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TAP-polymorphisms in juvenile onset psoriasis and psoriatic arthritis.

1996

Abstract Juvenile onset psoriasis is strongly associated with the HLA-class I genes Cw6 and B57 whereas patients with psoriatic arthritis show an increased frequency of HLA-B27. It is unclear whether additional major histocompatibility genes also increase disease susceptibility. The TAP genes (transporter associated with antigen processing) encode two membrane-spanning proteins that translocate antigenic peptides from the cytoplasm into the endoplasmic reticulum. Comparison of 60 patients with juvenile onset psoriasis, 63 psoriatic arthritis patients, and 101 caucasoid controls revealed an increase of the TAP1 ∗ 0101 allele in the psoriasis group, that could not be explained by linkage to o…

ImmunologyLinkage DisequilibriumMajor Histocompatibility ComplexPsoriatic arthritisATP Binding Cassette Transporter Subfamily B Member 3PsoriasismedicineImmunology and AllergyHumansPsoriasisAlleleATP Binding Cassette Transporter Subfamily B Member 2GenePolymorphism Geneticbiologybusiness.industryEndoplasmic reticulumArthritis PsoriaticHistocompatibility Antigens Class IGeneral MedicineTransporter associated with antigen processingHLA-DR Antigensmedicine.diseaseImmunologybiology.proteinTAP2ATP-Binding Cassette TransportersTAP1businessHuman immunology
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Functional cysteine-less subunits of the transporter associated with antigen processing (TAP1 and TAP2) by de novo gene assembly

2002

AbstractWithin the adaptive immune system the transporter associated with antigen processing (TAP) plays a pivotal role in loading of peptides onto major histocompatibility (MHC) class I molecules. As a central tool to investigate the structure and function of the TAP complex, we created cysteine-less human TAP subunits by de novo gene synthesis, replacing all 19 cysteines in TAP1 and TAP2. After expression in TAP-deficient human fibroblasts, cysteine-less TAP1 and TAP2 are functional with respect to adenosine triphosphate (ATP)-dependent peptide transport and inhibition by ICP47 from herpes simplex virus. Cysteine-less TAP1 and TAP2 restore maturation and intracellular trafficking of MHC c…

Models MolecularBiophysicsBiological Transport ActiveBiologyMajor histocompatibility complexTransfectionBiochemistryCell Linechemistry.chemical_compoundAdenosine TriphosphateStructural BiologyATP Binding Cassette Transporter Subfamily B Member 3Cysteine-scanning mutagenesisMHC class IGeneticsHumansCysteineATP Binding Cassette Transporter Subfamily B Member 2Molecular BiologyAntigen PresentationAntigen processingHistocompatibility Antigens Class ICell BiologyTransporter associated with antigen processingMolecular biologyRecombinant ProteinsCell biologyProtein SubunitschemistryAmino Acid SubstitutionAntigen processingPeptide transportMembrane proteinbiology.proteinAdenosine triphosphate-binding cassette transporterTAP2ATP-Binding Cassette TransportersTAP1Adenosine triphosphateFEBS Letters
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