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)

The major histocompatibility class I antigens, expressed in most somatic cells, have carbohydrate moieties. We constructed mutant mouse MHC class I genes in which codons for the N-linked glycosylation sites were replaced by those of other amino acids. L cell transformants expressing the nonglycosylated class I antigens allowed us to investigate biological roles of carbohydrates with the highest specificity possible. The nonglycosylated antigen was unchanged in its overall serological specificities, and was recognized by alloreactive cytotoxic T cells. Further, the antigen was capable of mediating cytotoxic activity of vesicular stomatitis virus-specific T cells. These studies indicate that carbohydrates are not essential for immunological function of the MHC class I antigens. Cell surface expression of the nonglycosylated antigen was markedly reduced as compared with the native antigen, which was not attributable to accelerated degradation or rapid shedding. We conclude that the primary role of carbohydrates of the class I antigens is to facilitate the intracellular transport of the nascent proteins to the plasma membrane. The possible involvement of carbohydrate-receptor interactions in this process is discussed.
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PMID:Expression and function of a nonglycosylated major histocompatibility class I antigen. 241 73

It has generally been assumed that most if not all CTL specific for vesicular stomatitis virus (VSV)-infected cells recognize the viral glycoprotein (G), an integral membrane protein abundantly expressed on infected cell surfaces. Using recombinant vaccinia viruses containing copies of cloned VSV genes to examine CTL recognition of VSV, we have confirmed that G is recognized by VSV-specific CTL. More interestingly, however, we have also found that nucleocapsid protein (N), an internal virion protein, can be detected on infected cell surfaces using mAb, and serves as a major target antigen for VSV-specific CTL. In contrast to the highly serotype-specific recognition of G, N is recognized by a major population of CTL able to lyse cells infected with either the Indiana or New Jersey VSV serotypes. Using target cells expressing a cloned MHC class I gene, we could directly show that CTL recognition of N occurs in the context of the MHC Ld molecule.
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PMID:Recognition of cloned vesicular stomatitis virus internal and external gene products by cytotoxic T lymphocytes. 301 49

To investigate the role of a cytokine in host defense against the vesicular stomatitis virus (VSV) infection of the central nervous system (CNS), IL-12 was injected i.p. into groups of 10 BALB/c mice on days -1, 0, 1, 2, and 3 postinfection. Four days postinfection, mice were examined. IL-12 strongly enhanced immunity to VSV infection in the CNS as demonstrated by 1) decreased VSV titers in brain homogenate of IL-12-injected mice compared with those of controls; 2) increased expression of inducible nitric oxide synthase in the CNS; 3) enhanced expression of both MHC class I and class II Ags in the CNS; 4) increased T cell infiltration in the CNS, especially in the olfactory bulb; and 5) diminished VSV-induced apoptosis in olfactory bulb. No detrimental effect was observed even with the 200 ng/mouse dose of IL-12. Protective effects of IL-12 were dose dependent. Collectively, these results demonstrate that exogenously added IL-12, even when injected peripherally, significantly enhances recovery from VSV infection of the CNS.
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PMID:IL-12 promotes enhanced recovery from vesicular stomatitis virus infection of the central nervous system. 749 54

Previously, we reported that expression of the murine beta 2-microglobulinb (beta 2mb) antigenic epitopes defined by the mAb S19.8 and 23 (SJL [beta 2ma] anti-B10.S beta 2mb]) was dependent upon association of beta 2m with MHC class I heavy chains. We have further explored the antigenic properties of beta 2m under circumstances requiring the induction of MHC class I surface expression with heavy chain-specific peptide-ligand. For the RMA-S cell line, which is class I surface null due to a defect in the TAP-2 peptide transporter, treatment with the H-2Kb-specific vesicular stomatitis virus-derived N p52-59 peptide resulted in the cell surface expression of the epitopes defined by the anti-H-2Kb mAb Y-3, as well as equally strong expression of the epitopes defined by the anti-beta 2mb mAb S19.8 and 23. Similarly, the FLU-NP p366-374 peptide induced H-2Db on the surface of RMA-S cells as determined by cytofluorometry with the mAb MKQ8; however, expression of the epitope defined by S19.8 was only partially recovered and no reactivity was observed for mAb 23. That the H-2Db heavy chain was assembled with beta 2mb on the cell surface was established from immunoprecipitation experiments with 125I-surface-radiolabeled RMA-S cells treated with FLU-NP p366-374; MKQ8 immunoprecipitated prominent heavy chain and beta 2m bands, whereas S19.8 and 23 isolated a weak beta 2m band (12-15% of that co-immunoprecipitated with MKQ8). These results are consistent with the observation that human beta 2m-deficient cells (designated FO-1) transfected with the B2mb allele were induced, in combination with the endogenous HLA class I heavy chains, to express the epitope defined by S19.8, but not mAb 23, whereas both were expressed when contransfection was performed with the H-2Kb gene. That the determinants recognized by S19.8 and 23 were formed by a discontinuous cluster of amino acids within beta 2m was established from experiments demonstrating that H-2Kb heavy chain assembled with a chimeric beta 2m molecule (comprising human beta 2m from 1-69 and mouse beta 2m from amino acid 70-99, including the polymorphic residue Ala 85) did not lead to expression of the S19.8 and 23 epitopes. The results of this study provide evidence that heavy chain polymorphism can affect the antigenic properties of beta 2m and offer insight into the basis by which CTL may react against beta 2mb when assembled with the H-2Kb molecule.
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PMID:MHC class I heavy chain-dependent expression of discontinuous antigenic epitopes on beta 2-microglobulinb is inducible with peptide-ligand. 753 Aug 67

A C164Y somatic mutation in the H-2Kb class I molecule causes a disruption of the alpha 2 domain disulfide bond and results in a loss of H-2Kb cell surface expression by the 69.9.15 cell line. In vitro culture of the somatic cell variant at 30 degrees C induced weak, but reproducible, expression of the H-2Kb mutant molecule on the cell surface, which suggests that a temperature-sensitive mutation was contributing to the H-2Kb null phenotype. Based on the inherent structural instability of the mutant H-2Kb molecules synthesized by 69.9.15 cells, we sought to determine the ability of high affinity peptide-ligand to counteract the null expression of H-2Kb. Treatment of 69.9.15 cells was performed with acid-eluted cell-derived peptides, as well as synthetic H-2Kb-restricted peptides, ovalbumin (OVA) p257-264 (YSIINFEKL), and vesicular stomatitis virus-nuclear protein p52-59 (RGYVYQGL). Whereas the endogenous and vesicular stomatitis virus peptides were ineffective at inducing H-2Kb expression at either 37 degrees C or 30 degrees C, treatment with the OVA peptide at 30 degrees C gave rise to dose-dependent enhancement in H-2Kb expression, an effect that was independent of exogenous sources of bovine beta 2-microglobulin at the time of peptide treatment. By comparison, expression of H-2Kb remained unaltered when cells were treated with the OVA peptide at 37 degrees C, consistent with the temperature-sensitive expression of the mutant molecules. Decay of H-2Kb from the cell surface was similar for both 69.9.15 and RMA-S cells, an indication that binding of OVA p257-264 provided the same level of stability for class I molecules with either a cis-(69.9.15) or trans-acting (RMA-S) defect in heavy chain transport. These data provide novel evidence that transport-defective MHC class I molecules, similar in nature to those encoded by class I genes isolated from human genomic libraries, i.e., the 12.4 pseudogene with a polymorphism at amino acid position 164 (C-->F), are subject to high affinity peptide-induced stabilization which reverses the class I null phenotype.
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PMID:Failure in expression of structurally altered (CYS164-->TYR) H-2Kb molecules is mitigated with high affinity peptide-ligand. 776 72

As an approach to determine the structural basis of interactions between T cell receptors (TCRs) and MHC class I/peptide complexes, the fine specificities of a panel of vesicular stomatitis virus (VSV)-specific CTL clones recognizing the antigenic peptide (nucleoprotein 52-59) and the class I (Kb) molecule were correlated with the TCR primary structure. Each TCR showed a distinct interaction pattern with N52-59 and the Kb molecule. The large majority of the TCRs expressed by the panel of CTL clones used V beta 13 gene segments that had randomly recombined with D beta and J beta gene segments. The alpha chains were from randomly assorted V alpha and J alpha gene segments. Thus, the panel was found to be a highly heterogeneous set of TCRs, each member of which appeared to have an unique surface interface area, the recognition site, that interacted with a complementary surface formed by the single peptide bound in the class I antigenic groove.
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PMID:Diversity of T cell receptors specific for the VSV antigenic peptide (N52-59) bound by the H-2Kb class I molecule. 774 62

In the class II region of the major histocompatibility complex (MHC(, four genes implicated in MHC class I-mediated antigen processing have been described. Two genes (TAP1 and TAP2) code for multimembrane-spanning ATP-binding transporter proteins and two genes (LMP2 and LMP7) code for subunits of the proteasome. While TAP1 and TAP2 have been shown to transport antigenic peptides from the cytosol into the endoplasmic reticulum, where the peptides associate with MHC class I molecules, the role of LMP2/7 in antigen presentation is less clear. Using antigen processing mutant T2 cells that lack TAP1/2 and LMP2/7 genes, it was recently shown that expression of TAP1/2 alone was sufficient for processing and presentation of the influenza matrix protein M1 as well as the minor histocompatibility antigen HA-2 by HLA-A2. To understand if presentation of a broader range of viral antigens occurs in the absence of LMP2/7, we transfected T2 cells with TAP1, TAP2 and either of the H-2Kb, Db or Kd genes and tested their ability to present vesicular stomatitis vires and influenza virus antigens to virus-specific cytotoxic T lymphocytes. We found that T2 cells, expressing TAP1/2 gene products, presented all tested viral antigens restricted through either the H-2Kb, Db or Kd class I molecules. We conclude that the proteasome subunits LMP2/7 as well as other gene products in the MHC class II region, except from TAP1/2, are not generally necessary for presentation of a broader panel of viral antigens to cytotoxic T cells. However, the present results do not exclude that LMP2/7 in a more subtle way may, or in rare cases completely, affect processing of antigen for presentation by MHC class I molecules.
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PMID:Presentation of viral antigens restricted by H-2Kb, Db or Kd in proteasome subunit LMP2- and LMP7-deficient cells. 805 44

Induction of immunity to a viral protein that had been transfected into a tumor cell line was studied. The nucleoprotein (NP) of vesicular stomatitis virus (VSV) was used as a model tumor-associated Ag after transfection into EL-4, and H-2b thymoma originating from C57BL/6 mice. The NP-transfected cell line (EL-4NP) was lysed by NP-specific CTL and was found to restimulate NP-specific CTL in vitro as efficiently as did VSV-infected macrophages. Despite both of these in vitro characteristics, C57BL/6 mice inoculated with EL-4NP did not mount a measurable NP-specific CTL response and developed a lethal tumor as rapidly as did mice given control EL-4. This lack of immunogenicity could not be explained by down-regulation of MHC class I molecules or by loss of NP; even EL-4NP cells metastasizing to the spleen kept their high restimulatory capacity and excellent target characteristics. However, once mice were immunized with VSV or with a vaccinia-VSV-NP recombinant virus they were protected against tumor growth of EL-4NP by CD8+ CTL but not by CD4+ T cells. Taken together, the failure of the tumor-associated Ag to induce a protective T cell response in vivo despite its excellent capacity to restimulate CTL in vitro may encourage adjuvant immunotherapy in cancer; even the effects of weakly immunizing tumor vaccines, e.g., recombinant viruses, may be efficiently amplified by tumor cells.
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PMID:Nonimmunogenic tumor cells may efficiently restimulate tumor antigen-specific cytotoxic T cells. 809 55

Immunostimulating complexes (ISCOMs), containing lipids, the saponin Quil A, and proteinaceous antigens, have been proven to vaccinate effectively CD8+ cytolytic T cells in vivo. However, conventional ISCOM technology is restricted to hydrophobic proteins or fatty acid-derivatized proteins or peptides. We therefore analysed whether Quil A-containing liposomes are an effective vehicle to shuttle hydrophilic proteins or peptides into the MHC class I pathway of antigen presentation resulting in the in vivo induction of antigen-specific cytolytic T cells (CTL). Liposomes were formed by a lipid dry-down method followed by resuspension with an aqueous solution containing protein/peptide and Quil A and then an extrusion step. Quil A-containing liposomes are an effective means to elicit a CD8+ CTL response to peptide antigen in vivo. CTL could be raised in C57B1/6 mice against ovalbumin (OVA) peptide 257-264 and vesicular stomatitis virus nucleoprotein 52-59, as well as in Balb/c mice against listeriolysin peptide 91-99 and cytomegalovirus pp89 168-176, demonstrating the versatility of this approach. The elicited response was peptide-specific, peptide dose-dependent and Quil A was necessary. Vaccination with liposomes entrapping the whole ovalbumin molecule or an extended (OVA) peptide 254-276 also yielded a CTL responsive to the immunodominant OVA peptide 256-264, implying cellular internalization and correct processing. Thus Quil A-containing liposomes appear to be a versatile vehicle to vaccinate CD8+ T cells in vivo; in addition, they could rapidly enhance the understanding of subunit vaccines and rules of antigen processing and peptide-MHC class I binding.
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PMID:Vaccination with immunodominant peptides encapsulated in Quil A-containing liposomes induces peptide-specific primary CD8+ cytotoxic T cells. 830 44

CTL recognize oligopeptides bound to MHC class I molecules. Immunization of animals with antigenic peptides has often failed to stimulate CTL responses. We confirm that immunizations with several peptides, including natural and optimally active antigenic sequences, do not prime cytotoxic immunity in mice. However, immunization with peptides together with human beta 2-microglobulin primes Ag-specific CTL. Priming is observed when animals receive injections either i.v. with ex vivo peptide/beta 2-microglobulin-pulsed cells or s.c. with an admixture of peptide and beta 2-microglobulin. beta 2-Microglobulin promotes the priming of CTL immunity if it is added with peptide, but not if it is added after cells are exposed to peptide. Synthetic peptides and mixtures of peptides from enzymatically cleaved Ag are immunogenic. When a tryptic digest of OVA or the synthetic peptide (OVA258-276) are used as immunogens, the CTL that respond recognize the endogenously processed epitope presented by an OVA-transfected target cell. The peptide + beta 2-microglobulin-primed CTL are CD4-CD8+ and are class I MHC restricted. Using the immunization protocol with beta 2-microglobulin, we have primed CTL responses with peptides from OVA, Sendai virus, and vesicular stomatitis virus. These results may explain previous failures to prime CTL with peptides in vivo and provide a novel approach for developing peptide-based vaccines for viral diseases.
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PMID:Peptide-priming of cytolytic T cell immunity in vivo using beta 2-microglobulin as an adjuvant. 838 32


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