Search results for "epitope(s)"
showing 10 items of 254 documents
Sodium Solute Symporter and Cadherin Proteins Act as Bacillus thuringiensis Cry3Ba Toxin Functional Receptors in Tribolium castaneum*
2013
Understanding how Bacillus thuringiensis (Bt) toxins interact with proteins in the midgut of susceptible coleopteran insects is crucial to fully explain the molecular bases of Bt specificity and insecticidal action. In this work, aminopeptidase N (TcAPN-I), E-cadherin (TcCad1), and sodium solute symporter (TcSSS) have been identified by ligand blot as putative Cry3Ba toxin-binding proteins in Tribolium castaneum (Tc) larvae. RNA interference knockdown of TcCad1 or TcSSS proteins resulted in decreased susceptibility to Cry3Ba toxin, demonstrating the Cry toxin receptor functionality for these proteins. In contrast, TcAPN-I silencing had no effect on Cry3Ba larval toxicity, suggesting that th…
Recombinant virus-like particles as a carrier of B- and T-cell epitopes of hepatitis C virus (HCV)
2005
The major aim of the project was the development of virus-like particles (VLP) displaying B- and T-cell epitopes of hepatitis C virus (HCV) proteins. To this end, hepatitis B virus core (HBc) particles were used as a carrier of HCV epitopes. Fragments of HCV genes encoding core (aa 98) and NS3 (aa 155) proteins were fused to the 3' terminus of the truncated HBV core gene. All recombinant plasmids led to relatively high levels of expression of chimeric proteins in E. coli, which resulted in the formation of complete "mature" VLP. Chimeric HBc/HCV VLPs were purified by combination of gel filtration and sucrose gradient centrifugation, and used for immunogenicity studies in mice. All variants …
SARS-CoV-2 in patients with cancer: possible role of mimicry of human molecules by viral proteins and the resulting anti-cancer immunity
2021
AbstractA few reports suggest that molecular mimicry can have a role in determining the more severe and deadly forms of COVID-19, inducing endothelial damage, disseminated intravascular coagulation, and multiorgan failure. Heat shock proteins/molecular chaperones can be involved in these molecular mimicry phenomena. However, tumor cells can display on their surface heat shock proteins/molecular chaperones that are mimicked by SARS-CoV-2 molecules (including the Spike protein), similarly to what happens in other bacterial or viral infections. Since molecular mimicry between SARS-CoV-2 and tumoral proteins can elicit an immune reaction in which antibodies or cytotoxic cells produced against t…
Translocation of the nuclear autoantigen La to cell surface: assembly and disassembly with the extracellular matrix.
1991
La (SS-B) protein is known as one major antigenic target for autoantibodies from patients with certain autoimmune diseases such as Sjogren's syndrome or Lupus Erythematosus. La protein belongs to the so called "extractable nuclear antigens". Here we report that La antigen is not restricted to the nucleus as one might deduce from the exclusive nuclear staining pattern of patient anti-La antibodies but after stimulation of serum-starved cells with 10% fetal calf serum (FCS) appears and stays for at least 45 min at the outer surface of CV-1 cells being available for binding of anti-La antibodies. In addition we found that a minor part of La antigen associates with the extracellular fibronectin…
Recognition of human renal cell carcinoma and melanoma by HLA-A2-restricted cytotoxic T lymphocytes is mediated by shared peptide epitopes and up-reg…
1996
Cytotoxic T lymphocytes (CTL) have previously been isolated from peripheral blood of patients with renal cell carcinoma (RCC). The CD8-positive CTL line MZ1257-CTL-5 (CTL-5) has been shown to lyse autologous cultured RCC cells in an HLA-A2 restricted fashion. Allogeneic, HLA-A2-matched RCC and melanoma cell lines were also lysed by CTL-5, suggesting that melanoma and renal cancer share antigenic determinants. The aim of the study was to determine whether RCC and melanoma share peptide epitopes that are recognized by CTL-5 in the context of HLA-A2 molecules. Peptides were acideulated from various cell lines, separated by reversed phase high performance liquid chromatography (RP-HPLC), and as…
Interleukin 4 suppresses primary interferon gamma response by T cells immunized in vivo and cultured in vitro with interleukin 2.
1996
This paper describes a novel primary in vivo/in vitro culture system which allows analysis of the effect of IL-4 added to culture 1 day after immunization on the production of IFN-gamma. Mice are immunized epicutaneously with picryl chloride (TNP) and draining lymph node cells were harvested 1 day later. These cells (1 day lymph node cells), when cultured in vitro for 3 days in the presence of IL-2, either continuously or as a pulse, give an IFN-gamma response on reexposure to antigen 3 days later. This production of IFN-gamma is both antigen-specific and genetically (MHC)-restricted and is due to both CD8+ and CD4+ T cells. However, if 1 day lymph node cells are cultured with both IL-2 and…
Molecular mimicry may explain multi-organ damage in COVID-19
2020
International audience
Identification of an endothelial cell binding site on kininogen domain D3
1995
High and low molecular mass kininogen, two multidomain plasma proteins, bind to endothelial cells, platelets, and neutrophils in the intravascular compartment. The specific cell attachment site on their common heavy chain is mediated by domain-3, a cystatin-like structure with inhibitory capacity for papain-like proteinases (Jiang, Y., Müller-Esterl, W., and Schmaier, A. H. (1992) J. Biol. Chem. 267, 3712-3717). In this report, the domain-3 cell binding site is determined by an antibody-directed strategy. The epitope of monoclonal antibody HKH15, which binds to domain-3 and blocks the binding of kininogens to platelets and endothelial cells, was mapped using seven synthetic peptides, which …
Mapping of the high molecular weight kininogen binding site of prekallikrein. Evidence for a discontinuous epitope formed by distinct segments of the…
1993
Prekallikrein, a glycoprotein involved in contact phase activation, circulates in plasma in the form of a binary complex with high molecular weight kininogen (H-kininogen). The binding to H-kininogen is mediated by the prekallikrein heavy chain consisting of four repetitive domains, A1-A4. To define more precisely the region(s) involved in kininogen binding, we have employed an affinity cross-linking strategy with a synthetic peptide of 31 residues which mimics the prekallikrein binding site of H-kininogen. Cross-linking of the radiolabeled peptide to (pre)kallikrein revealed a binding segment in the NH2-terminal portion of the prekallikrein heavy chain; another binding segment was located …
Inducible lectins with galectin properties and human IL1alpha epitopes opsonize yeast during the inflammatory response of the ascidian Ciona intestin…
2007
Studies on inducible ascidian lectins may shed light on the evolutionary emergence of cytokine functions. Here, we show that the levels of opsonins, with IL1alpha-epitopes, increase in Ciona intestinalis hemolymph as a response to an inflammatory stimulus and, in particular, to intratunic injection of lipopolysaccharide (LPS). The inflammatory agent promptly (within 4 h) enhances Ca(2+)-independent serum hemagglutinating and opsonizing activities, which are both inhibited by D-galactose and D-galactosides (alpha-lactose, N-acetyl-D-lactosamine, thio-digalactoside), suggesting that anti-rabbit erythrocyte lectins with galectin properties are involved as opsonins. Inducible galectin molecules…