Search results for "Histocompatibility"
showing 10 items of 473 documents
Biochemical analysis of class II antigens. Identification of a two- and a three-polypeptide chain complex of I-A locus equivalent molecules in the ra…
1983
The polypeptide chain composition of class II antigens from LEW rat spleen cells was studied utilizing cross-reactive mouse alloantiserum A. TH anti-A.TL (specificity anti-Iak) and the monoclonal antibodies MRC-OX6 and MRC-OX3 for immunoprecipitation. Two-dimensional gel mapping of A. TH anti-A. TL immunoprecipitates revealed that, as in the mouse, two groups of class II antigens exist corresponding to I-A and I-E locus equivalent structures. In the absence of reducing agents three monomeric chains α, 36 kDa (p36); γ, 33 kDa (p33); and β, 23 kDa (p23), were detected for I-A equivalent antigens, whereas I-E equivalent molecules separated into five monomeric chains: α, 37 kDa (p37); γ, 33 kDa…
Immune evasion proteins of murine cytomegalovirus preferentially affect cell surface display of recently generated peptide presentation complexes.
2009
CD8 T cells recognize infected cells by interaction of their T-cell receptor (TCR) with a cell surface presentation complex composed of a cognate antigenic peptide bound to a presenting allelic form of a major histocompatibility complex class I (MHC-I) glycoprotein (77, 85, 97, 98). The number of such “peptide receptors” per cell has been estimated to be on the order of 105 to 106 for each MHC-I allomorph (for a review, see reference 82). Viral antigenic peptides are generated within infected cells by proteolytic processing of viral proteins, usually in the proteasome, and associate with nascent MHC-I proteins in the endoplasmic reticulum (ER) before the peptide-MHC (pMHC) complexes travel …
Genome-wide association study of follicular lymphoma identifies a risk locus at 6p21.32
2010
To identify susceptibility loci for non-Hodgkin lymphoma subtypes, we conducted a three-stage genome-wide association study. We identified two variants associated with follicular lymphoma at 6p21.32 (rs10484561, combined P = 1.12 × 10-29 and rs7755224, combined P = 2.00 × 10-19; r2 = 1.0), supporting the idea that major histocompatibility complex genetic variation influences follicular lymphoma susceptibility. We also found confirmatory evidence of a previously reported association between chronic lymphocytic leukemia/small lymphocytic lymphoma and rs735665 (combined P = 4.24 × 10-9). © 2010 Nature America, Inc. All rights reserved.
Presentation of an Immunodominant Immediate-Early CD8+ T Cell Epitope Resists Human Cytomegalovirus Immunoevasion.
2013
Control of human cytomegalovirus (HCMV) depends on CD8+ T cell responses that are shaped by an individual's repertoire of MHC molecules. MHC class I presentation is modulated by a set of HCMV-encoded proteins. Here we show that HCMV immunoevasins differentially impair T cell recognition of epitopes from the same viral antigen, immediate-early 1 (IE-1), that are presented by different MHC class I allotypes. In the presence of immunoevasins, HLA-A- and HLA-B-restricted T cell clones were ineffective, but HLA-C*0702-restricted T cell clones recognized and killed infected cells. Resistance of HLA-C*0702 to viral immunoevasins US2 and US11 was mediated by the alpha3 domain and C-terminal region …
The DNA-binding subunit p140 of replication factor C is upregulated in cycling cells and associates with G 1 phase cell cycle regulatory proteins
1999
The DNA-binding subunit of replication factor C (RFCp140) plays an important role in both DNA replication and DNA repair. The mechanisms regulating activation of RFCp140 thereby controlling replication and cellular proliferation are largely unknown. We analyzed protein expression of RFCp140 during cell cycle progression and investigated the association of RFCp140 with cell cycle regulatory proteins in cell lines of various tissue origin and in primary hematopoietic cells. Western and Northern blot analyses of RFCp140 from synchronized cells showed downregulation of RFCp140 when cells enter a G0-like quiescent state and upregulation of RFCp140 in cycling cells. Translocation from the cytopla…
Detailed characterization of human Mycobacterium tuberculosis specific HLA-E restricted CD8+TÂ cells
2018
HLA-E presented antigens are interesting targets for vaccination given HLA-Esâ essentially monomorphic nature. We have shown previously that Mycobacterium tuberculosis (Mtb) peptides are presented by HLA-E to CD8+effector TÂ cells, but the precise phenotype and functional capacity of these cells remains poorly characterized. We have developed and utilized in this study a new protocol combining HLA-E tetramer with intracellular staining for cytokines, transcription factors and cytotoxic molecules to characterize these cells in depth. We confirm in this study the significantly increased ex vivo frequency of Mtb-peptide/HLA-E-TM+CD8+TÂ cells in the circulation of patients with active tubercu…
Immunosurveillance of lung melanoma metastasis in EBI-3-deficient mice mediated by CD8+ T cells.
2008
Abstract EBV-induced gene 3 (EBI-3) codes for a soluble type I receptor homologous to the p40 subunit of IL-12 that is expressed by APCs following activation. In this study, we assessed the role of EBI-3 in a model of lung melanoma metastasis. Intravenous injection of the B16-F10 cell line resulted in a significant reduction of lung tumor metastasis in EBI-3−/− recipient mice compared with wild-type mice. The immunological finding accompanying this effect was the expansion of a newly described cell subset called IFN-γ producing killer dendritic cells associated with CD8+ T cell responses in the lung of EBI-3−/− mice including IFN-γ release and TNF-α-induced programmed tumor cell death. Depl…
Generation of tumor-reactive CTL against the tumor-associated antigen HER2 using retrovirally transduced dendritic cells derived from CD34+ hemopoiet…
2000
Abstract Ag-specific CD8+ CTL are crucial for effective tumor rejection. Attempts to treat human malignancies by adoptive transfer of tumor-reactive CTL have been limited due to the difficulty of generating and expanding autologous CTL with defined Ag specificity. The current study examined whether human CTL can be generated against the tumor-associated Ag HER2 using autologous dendritic cells (DC) that had been genetically engineered to express HER2. DC progenitors were expanded by culturing CD34+ hemopoietic progenitor cells in the presence of the designer cytokine HyperIL-6. Proliferating precursor cells were infected by a retroviral vector encoding the HER2 Ag and further differentiated…
Consequences of antigen self-presentation by tumor-specific cytotoxic T cells.
2000
Abstract CDS-positive cytotoxic T cells (CTL) recognize antigenic peptides in combination with major histocompatibility complex (MHC) class I molecules on the surface of syngeneic antigen presenting cells (APC). In the present paper we show that cells from tumor antigen-specific CTL clones present their cognate antigenic peptide to other CTL from the same clone. Inter-CTL peptide presentation resulted in activation of the cells of one CTL clone to MHC-unrestricted lysis of bystander cells. In contrast to the behaviour of this clone, another CTL clone did not lyse bystander cells after incubation with the cognate peptide, but was activated to self-destruction. The human herpes virus Epstein-…
FOXP3 Inhibitory Peptide P60 Increases Efficacy of Cytokine-induced Killer Cells Against Renal and Pancreatic Cancer Cells
2019
Background/aim Cytokine-induced killer (CIK) cells are ex vivo expanded major histocompatibility complex (MHC)-unrestricted cytotoxic cells with promising effects against a variety of cancer types. Regulatory T-cells (T-reg) have been shown to reduce the effectiveness of CIK cells against tumor cells. Peptide P60 has been shown to inhibit the immunosuppressive functions of T-regs. This study aimed at examining the effect of p60 on CIK cells efficacy against renal and pancreatic cancer cells. Materials and methods The effect of P60 on CIK cytotoxicity was examined using flow cytometry, WST-8-based cell viability assay and interferon γ (IFNγ) ELISA. Results P60 treatment resulted in a signifi…