Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038362 (stomatitis)
 8,852 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A focus-forming assay for the quantification of defective interfering (DI) particles of vesicular stomatitis virus (VSV) is described. This assay is based on the procedures described for lymphocytic choriomeningitis (LCM) virus by Popescu et al. (1976). Under appropriate conditions this focus-forming assay can quantify fewer than 100 DI particles/ml in a preparation containing a large number of infectious particles.
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PMID:A sensitive method for quantification of vesicular stomatitis virus defective interfering particles: focus forming assay. 624 38

Murine cytomegalovirus (MCMV) does not productively infect OTT6050AF1 BrdU, F9, or PCC4 undifferentiated murine teratocarcinoma cell lines, as shown by immunofluorescence assays for viral antigens and by plaque assays for infectious virus. However, these cells were infected by a variety of other viruses. MCMV does productively infect PYS2 and OTT F12 differentiated murine teratocarcinoma cell lines. The replication of MCMV in the pluripotent PCC4 cell line was examined in detail. Undifferentiated PCC4 cells could be differentiated when propagated in the presence of dimethylacetamide, as judged by changes in the expression of H-2 antigens on the cell surface. Several viruses, including lymphocytic choriomeningitis virus, herpes simplex virus type 1, and vesicular stomatitis virus, replicated to a similar extent in differentiated and undifferentiated PCC4 cells. MCMV did productively infect differentiated PCC4 cells. In contrast, MCMV did not produce infectious virus, viral antigens, or substantial viral RNA in undifferentiated PCC4 cells. The molecular block of MCMV replication occurred at the level of MCMV RNA transcription. Undifferentiated PCC4 cells have receptors for MCMV and bind similar amounts of radiolabeled virus as differentiated PCC4 cells. After MCMV binds to its receptors on undifferentiated cells, MCMV penetrates the plasma membrane and is transported to the cells' nuclei. MCMV DNA was present in the cytoplasm, and small amounts of MCMV RNA (less than 17 percent of that found in MCMV-infected differentiated PCC4 cells) were found in the nucleus. However, MCMV RNA was not detected in the cytoplasm of undifferentiated cells. A latent infection was established by infecting undifferentiated PCC4 cells with MCMV, inactivating residual infectivity with antibodies to MCMV, and propagating cells under conditions that maintained the undifferentiated state. These MCMV-infected undifferentiated cells did not produce infectious virus, viral antigens, or viral RNA but did contain viral DNA detectable by DNA-DNA hybridization kinetics. Latency was terminated and infectious virus was made when such undifferentiated cells were induced to differentiate.
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PMID:Cytomegalovirus causes a latent infection in undifferentiated cells and is activated by induction of cell differentiation. 627 94

Murine F9 and PCC4 teratoma cells do not express H-2 major transplantation antigens according to virus-specific T-lymphocyte cytotoxic or serological assays. However, such cells can be infected with and readily replicate many types of viruses (coxsackie B 3, mouse hepatitis, Sindbis, Semliki Forest [SFV], lymphocytic choriomeningitis, Pichinde, vesicular stomatitis, herpes simplex type 1) to the same extent as do murine F12 teratoma cells and mouse embryo fibroblasts, all of which express the H-2 determinants. In contrast, F9 and PCC4 cells are not productively infected with murine cytomegalovirus, whereas F12 and mouse embryo fibroblast cells are. In addition to replicating in H-2-negative murine teratoma cells, SFV replicates in H-2-negative murine lymphoblastoid cells. The ability of SFV to infect cells without H-2 antigens and then to effect viral antigenic expression in the cells' cytoplasm and on their surface with similar kinetics and in equivalent amounts as cells with H-2 antigens indicates that the H-2 receptor is not needed for SFV infection. Daudi cells, which lack HLA antigens, block the replication of SFV. This occurs at some point after receptor binding, as demonstrated by diminished viral mRNA. In addition, a possible membrane defect precludes viral exit in Daudi cells transfected with SFV infectious RNA. These results indicate that a cell's possession of H-2 antigens is not a requirement for SFV infection and that major histocompatibility complex antigens are not specific receptors for this virus.
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PMID:Does the major histocompatibility complex serve as a specific receptor for Semliki Forest virus? 737 8

We examined T cell development and T cell repertoire in transgenic mice expressing a single T cell receptor (TCR) alpha chain derived from the H-2Db-lymphocytic choriomeningitis virus (LCMV)-specific cytolytic T lymphocyte (CTL) clone P14. To generate these alpha P14 mice, mice transgenic for the P14 TCR alpha chain were backcrossed to TCR alpha-deficient mice. Thymi from alpha P14 mice exhibited a marked decrease of mature CD4+8- and CD8+4- single-positive thymocytes comparable to thymi from TCR alpha-deficient mice. Correspondingly, the number of peripheral T cells was reduced in the CD4 (tenfold) and in the CD8 (twofold) subsets when compared to normal mice. T cells from alpha P14 mice generated a primary anti-LCMV CTL response when stimulated in vitro with LCMV in contrast to normal mice which require priming in vivo; elimination of LCMV in vivo was, however, not improved. Flow cytometric analysis of T cells with V beta-specific antibodies showed a diverse endogenous TCR V beta repertoire. Functional analysis of the T cell repertoire, however, revealed a strongly reduced (30-fold) allogeneic and the absence of a vesicular stomatitis virus-specific CTL response and an impaired ability to provide T cell help for antibody isotype switching. Thus, T cell selection in the thymus was impaired and the T cell repertoire was limited in mice expressing only one type of TCR alpha chain.
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PMID:T cell development and repertoire of mice expressing a single T cell receptor alpha chain. 758 40

Antiviral immune responses of mice lacking interleukin-2 (IL-2) or IL-4 or both IL-2 and IL-4 (IL-2/4) were compared by using different viruses. Primary cytotoxic T-lymphocyte (CTL) responses against lymphocytic choriomeningitis virus (LCMV) were only moderately reduced in mice lacking IL-2 and were normal in mice lacking IL-4. Mice deficient in both interleukins exhibited variable and more strongly reduced but nevertheless in vivo protective LCMV-specific CTL responses. Similar results were obtained with vaccinia virus. Upon virus-specific restimulation in vitro, spleen cells from IL-2- and IL-2/4-deficient mice failed to generate CTL responses against virus-infected target cells, whereas the response of mice deficient in only IL-4 was comparable to that of control mice. The addition of IL-2 during in vitro restimulation completely restored the responses of both IL-2 and IL-2/4-deficient mice. T-helper-cell-independent immunoglobulin M and T-helper-cell-dependent immunoglobulin G antibody responses against vesicular stomatitis virus glycoprotein were within normal ranges for the various mutant mice. After LCMV infection, specific antibody responses against LCMV nucleoprotein were reduced four- to eightfold. These results show that mice lacking IL-2/4 have an overall tendency to exhibit more severely reduced CTL responses than IL-2- or IL-4-deficient mice. Nevertheless, and surprisingly, in vivo protective immune responses were mounted in the absence of IL-2/4, suggesting that besides a minor contribution from IL-4, other interleukins compensate in vivo for the lack of IL-2 in IL-2-deficient mice.
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PMID:Antiviral immune responses in mice deficient for both interleukin-2 and interleukin-4. 760 51

Presentation of peptides derived from endogenous proteins on class I molecules needs functional TAP peptide transporters. To reveal whether class I-associated presentation of exogenous proteins also required the presence of TAP transporters, we assessed in vitro the ability of spleen cells and macrophages from TAP1-deficient mice (TAP1-/-) to present peptides derived from exogenous recombinant viral proteins on their class I molecules. We found that recombinant glyco- and nucleoprotein from lymphocytic choriomeningitis virus and nucleoprotein of vesicular stomatitis virus were presented as efficiently by TAP1-/- cells as by control cells. Peptide regurgitation was not involved. Since particulate, non-replicating antigens can efficiently prime anti-viral cytotoxic T cells in vivo, this new, TAP-independent pathway of class I-associated antigen presentation may be applicable for vaccine strategies.
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PMID:TAP1-independent loading of class I molecules by exogenous viral proteins. 761 1

T cell receptor stimulation without costimulation is insufficient for the induction of an optimal immune response. It is thought that engagement of the CD28 molecule with its ligand B7 provides an essential costimulatory signal without which full activation of T cells cannot occur. A mouse strain with a defective CD28 gene was established. Development of T and B cells in the CD28-deficient mice appeared normal. However, T lymphocytes derived from CD28-/- mutant mice had impaired responses to lectins. Lectin stimulation did not trigger interleukin-2 (IL-2) production, IL-2 receptor alpha expression was significantly decreased, and exogenous IL-2 only partially rescued the CD28 defect. Basal immunoglobulin (Ig) concentrations in CD28-deficient mice were about one-fifth of those found in wild-type controls, with low titers of IgG1 and IgG2b but an increase in IgG2a. In addition, activity of T helper cells in CD28-/- mice was reduced and immunoglobulin class switching was diminished after infection with vesicular stomatitis virus. However, cytotoxic T cells could still be induced and the mice showed delayed-type hypersensitivity after infection with lymphocytic choriomeningitis virus. Thus, CD28 is not required for all T cell responses in vivo, suggesting that alternative costimulatory pathways may exist.
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PMID:Differential T cell costimulatory requirements in CD28-deficient mice. 768 39

The secretory (tumor necrosis factor, TNF-alpha; nitrite) and cellular response (mitochondrial respiration, TNF-alpha-independent tumoricidal activity) of a pure, lymphocyte-free population of resting, unprimed rat bone marrow-derived mononuclear phagocytes (BMM phi) to direct interaction with viruses, protozoa, and fungi was assessed and compared with that triggered by bacterial agents and interferon-gamma (IFN-gamma). Viruses (herpes simplex, vaccinia, poliomyelitis, vesicular stomatitis, lymphocytic choriomeningitis, Sendai), protozoa (Trypanosoma brucei, Giardia lamblia), and fungi (Penicillium, Trichosporon, Fusarium, Rhizopus, Aspergillus, Geotrichum species) affected primarily the secretion of TNF-alpha and mitochondrial respiration of BMM phi; their effects on the secretion of nitrite and on tumoricidal activity were at best marginal. Collectively, the macrophage response to viruses, protozoa, and fungi was less varied and less marked than that to bacterial agents (intact organisms, peptidoglycan, lipoteichoic acid, lipopolysaccharide) and IFN-gamma.
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PMID:Macrophage response to viruses, protozoa, and fungi: secretory and cellular activities induced in resting unprimed bone marrow-derived mononuclear phagocytes. 799 64

CD8 is a cell surface glycoprotein on major histocompatibility complex class I-restricted T cells. Thymocytes and most peripheral T cells express CD8 as heterodimers of CD8 alpha and CD8 beta. The intestinal intraepithelial lymphocytes (IEL), which have been suggested to be generated extrathymically, express CD8 predominantly as homodimers of CD8 alpha. We have generated CD8 beta gene-targeted mice. CD8 alpha+ T cell population in the thymus and in most peripheral lymphoid organs was reduced to 20-30% of that in wild-type littermates. CD8 alpha expression on thymocytes and peripheral T cells also decreased to 44 and 53% of the normal levels, respectively. In contrast, neither the population size nor the CD8 alpha expression level of CD8 alpha+ IEL was reduced. This finding indicates that CD8 beta is important only for thymic-derived CD8+ T cells. The lack of CD8 beta reduces but does not completely abolish thymic maturation of CD8+ T cells. Our result also reveals the role of CD8 beta in regulating CD8 alpha expression on thymic derived T cells. Peripheral T cells in these mice were efficient in cytotoxic activity against lymphocytic choriomeningitis virus and vesicular stomatitis virus, suggesting that CD8 beta is not essential for the effector function of CD8+ T cells.
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PMID:Reduced thymic maturation but normal effector function of CD8+ T cells in CD8 beta gene-targeted mice. 806 43

Induction of CD8+, class I-restricted T cells by non-infectious, exogenous antigens has been documented for model protein antigens such as ovalbumin and for major histocompatibility complex restricted short peptides in viral and tumor systems. However, the protective capacity of cytotoxic T cells induced by conventional proteins has not been tested in vivo so far. We, therefore, evaluated the induction of protective cytotoxic T cells against three different full-length recombinant viral proteins derived from a baculovirus expression system, i.e. the glycoprotein and nucleoprotein of lymphocytic choriomeningitis virus (LCMV) and the nucleoprotein of vesicular stomatitis virus (VSV). These viral proteins induced cytotoxic T cells in a T helper cell-independent fashion which lysed infected target cells in vitro and protected mice from viral replication, immunopathological disease and growth of a tumor expressing the same antigen as a tumor antigen. These results are surprising, since it had been shown earlier for completely inactivated nonreplicating viral vaccines and again here for beta-propiolactone-inactivated VSV or UV-light inactivated LCMV that nonreplicating viral vaccines were incapable of inducing protective cytotoxic T cells. Our data show that immunization of mice with as little as 10 micrograms of non-infectious viral proteins triggered long-lasting CD8+ T cell-mediated antiviral immunity. It was found that the protein alone was only weakly able to induce cytotoxic T cells, and that association with cellular debris functioned as an adjuvant. These findings may be relevant for our understanding of the phenomenon of cross-priming and have obvious implications for vaccine strategies.
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PMID:Induction of protective cytotoxic T cells with viral proteins. 808 38


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