ovalbumin and Cell-Transformation--Viral

Topics: Animals; Avidin; Bacteria; Biotin; Cell Transformation, Viral; Chickens; Enzyme Inhibitors; Female; Inflammation; Macrophages; Male; Ovalbumin; Oviducts; Protein Conformation

Topics: Animals; Antigen Presentation; Antigens; Cell Differentiation; Cell Line; Cell Transformation, Viral; Dendritic Cells; Histocompatibility Antigens Class II; In Vitro Techniques; Interferon Type I; Interferon-gamma; Lymphocyte Activation; Lymphocyte Culture Test, Mixed; Mice; Mice, Knockout; Ovalbumin; Receptors, Interferon; T-Lymphocytes

Small peptides, derived from endogenous proteins bind within the antigen binding groove created by the beta-pleated sheets and alpha helices of the alpha 1 and alpha 2 domains of the class I molecule of the major histocompatibility complex (MHC). However, the precise role of peptide in class I MHC conformation remains unclear. Here, we have shown that, in at least some instances, changes induced in the MHC molecule by the binding of distinct peptides can be identified as specific alterations in serological epitopes expressed on the class I protein. The nature of specific peptides expressed by class I-bearing cells may, therefore, have a dramatic influence on T cell development, self-tolerance, and alloreactivity.

Topics: Amino Acid Sequence; Animals; Antibodies, Monoclonal; Binding Sites; Cell Transformation, Viral; Histocompatibility Antigens Class I; Humans; Lymphoma; Major Histocompatibility Complex; Molecular Sequence Data; Mutagenesis, Site-Directed; Ovalbumin; Peptides; Protein Conformation; Rauscher Virus; Tumor Cells, Cultured

Friend-virus transformed erythroblasts (HFL cells) were incubated in solutions containing up to 3 different proteinaceous compounds at pH 7.2 or 5.5 at 5 degrees C. The specificity of interaction of each compound with the cell surface was determined by comparing the amounts of each compound adsorbed and bound in the presence of 2 or 3 different compounds or after prior binding of another compound to the amounts when the individual compounds alone interacted with the cells. At pH 7.2, ovalbumin and gelatin apparently interacted with cell surface components common to both proteins, as indicated by a decrease (up to 80%) in the amount of each compound adsorbed and bound in the presence, or after the binding, of the other compound. The relative amounts of each compound that interacted were different at pH 5.5 and pH 7.2. Gelatin and poly-L-lysine interacted mainly with different components at pH 7.2, whereas common components appeared to be involved at pH 5.5. Concanavalin A interacted preferentially with components that it shared with lysozyme at both pH values. In addition to variations in interactions with changes in pH and type of compound, variations occurred with changes in concentration of the compounds and with their sequence of addition to the cells. Comparative studies with horse red blood cells showed that the interactions differed markedly with cell type.

Topics: Adsorption; Animals; Cell Line; Cell Transformation, Viral; Concanavalin A; Erythroblasts; Erythrocyte Membrane; Erythrocytes; Friend murine leukemia virus; Gelatin; Horses; Hydrogen-Ion Concentration; Mice; Muramidase; Ovalbumin; Peptides; Polylysine; Sarcosine

Synthesis and secretion of avidin was studied in cultured chicken embryo fibroblasts infected with transforming retroviruses (Rous sarcoma virus, its mutants temperature-sensitive for transformation, OK-10 virus) or a nontransforming retrovirus (RAV-1). Avidin was detectable in both transformed and untransformed cultures, and was identical to chicken egg white avidin by several criteria: biotin-binding, heat-induced biotin exchange, subunit size (mol. wt. 15 600), immunoprecipitation of metabolically labeled proteins and immunoblotting. Transformation increased the production of avidin up to 50-fold, but several experiments suggested that the induction was not a direct consequence of virus-induced cell transformation. The production of avidin seemed to relate to cellular damage both in cultures of virus-transformed and of normal fibroblasts. It may represent a response to cellular damage and viral transformation may activate the process.

Topics: Alpharetrovirus; Animals; Avian Sarcoma Viruses; Avidin; Cell Transformation, Viral; Chick Embryo; Fibroblasts; Hot Temperature; Kinetics; Molecular Weight; Mutation; Ovalbumin

Antigen-specific immune T lymphocytes of male C57BL/6 mice were enriched in vitro on monolayers of antigen-pulsed syngeneic macrophages. The cells were treated in vitro with RadLV and inoculated intrathymically into irradiated female C56BL/6 animals. Thymomas arising in the inoculated recipients were characterized as donor- (male) type according to their karyotype. In vivo and in vitro cell lines were established from the primary lymphomas, two of which (designated ROT/6.1 and ROT/6.2) were capable of providing antigen- (carrier) specific help in normal or preimmunized mice. None of the lymphomas could induce antigen-specific DTH reaction. Five months after their establishment, ROT/6.2 alone retained its carrier specificity. ROT/6.2 consisted mainly of Lyt-1+ cells, whereas the ROT/6.1 population was more heterogeneous and contained Lyt-1+, Lyt-2+, and Lyt-3+ cells. The carrier specificity of the latter may have been lost due to selection against the specific helper cells during prolonged passages.

Topics: Animals; Antigens, Ly; Cell Line; Cell Transformation, Viral; Dinitrobenzenes; Epitopes; Female; Genetic Carrier Screening; Hypersensitivity, Delayed; Leukemia Virus, Murine; Leukemia, Experimental; Leukemia, Radiation-Induced; Male; Mice; Mice, Inbred C57BL; Ovalbumin; T-Lymphocytes; Thymoma

Topics: Animals; Cell Aggregation; Cell Transformation, Neoplastic; Cell Transformation, Viral; Concanavalin A; Erythroblasts; Erythrocyte Membrane; Erythrocytes; Friend murine leukemia virus; Gelatin; Mice; Microscopy, Electron, Scanning; Microvilli; Muramidase; Ovalbumin; Peptides; Polylysine; Proteins; Sarcosine; Surface Properties

In synchronized translation experiments in the wheat germ and reticulocyte lysate systems, ovalbumin (385 amino acids) was glycosylated by and segregated in dog pancreatic microsomes only if microsomes were added before the nascent ovalbumin polypeptide contained less than 150 amino acids. This would place the "signal" sequence of ovalbumin prior to residue 150, in contrast to a previous report.

Topics: Amino Acid Sequence; Animals; Cell Line; Cell Transformation, Viral; Cricetinae; Dogs; Kidney; Microsomes; Ovalbumin; Pancreas; Plants; Protein Biosynthesis; Reticulocytes; RNA, Messenger; Triticum; Vesicular stomatitis Indiana virus

Equilibrium adsorption and binding isotherms at different pH values and temperatures were used to study the mechanism of interaction of 6 proteinaceous compounds with erythroblasts transformed by Friend virus (HFL cells). The molecular weight of the adsorbate appeared to influence the amounts absorbed: fewer moles interacted with increasing molecular weight. The pI value affected binding of adsorbates of low molecular weight in an almost linear way: more moles bound with increasing pI value. Polylysine and polysarcosine absorbed to labile components on the cell surface. Gelatin, lysozyme, ovalbumin, and polysarcosine interacted with pronase-susceptible, Concanavalin A and polylysine with non-susceptible components.

Topics: Adsorption; Animals; Cell Line; Cell Transformation, Viral; Erythroblasts; Erythrocytes; Friend murine leukemia virus; Gelatin; Hydrogen-Ion Concentration; Mice; Molecular Weight; Muramidase; Ovalbumin; Peptides; Proteins; Temperature

Topics: Alpharetrovirus; Cell Division; Cell Line; Cell Transformation, Neoplastic; Cell Transformation, Viral; Genes; Genes, Viral; Globins; Ovalbumin; RNA, Messenger; Transcription, Genetic