| the receptor for mouse hepatitis virus in the resistant mouse strain sjl is functional: implications for the requirement of a second factor for viral infection. | the sjl mouse strain is resistant to infection by some strains of the murine coronavirus mouse hepatitis virus (mhv), such as jhm and a59. the block to virus infection has been variously attributed to defects in virus receptors or virus spread. since the cellular receptors for mhv, mmcgm1 and mmcgm2, have recently been identified as members of the carcinoembryonic antigen family, we reexamined the possible defectiveness of the mhv receptors in sjl mouse strain. cloning and sequencing of the cdna ... | 1992 | 1279194 |
| coronavirus species specificity: murine coronavirus binds to a mouse-specific epitope on its carcinoembryonic antigen-related receptor glycoprotein. | like most coronaviruses, the coronavirus mouse hepatitis virus (mhv) exhibits strong species specificity, causing natural infection only in mice. mhv-a59 virions use as a receptor a 110- to 120-kda glycoprotein (mhvr) in the carcinoembryonic antigen (cea) family of glycoproteins (g. s. dveksler, m. n. pensiero, c. b. cardellichio, r. k. williams, g. s. jiang, k. v. holmes, and c. w. dieffenbach, j. virol. 65:6881-6891, 1991; and r. k. williams, g. s. jiang, and k. v. holmes, proc. natl. acad. sc ... | 1992 | 1279203 |
| sequence analysis of the spike protein gene of murine coronavirus variants: study of genetic sites affecting neuropathogenicity. | mouse hepatitis virus (mhv), a coronavirus, causes encephalitis and demyelination in susceptible rodents. previous investigations have shown that the mhv spike (s) protein is a critical determinant of viral tropism and pathogenicity in mice and rats. to understand the molecular basis of mhv neuropathogenesis, we studied the spike protein gene sequences of several neutralization-resistant variants of the jhm strain of mhv, which were selected with monoclonal antibodies (mabs) specific for the s p ... | 1992 | 1310195 |
| acute and late disease induced by murine coronavirus, strain jhm, in a series of recombinant inbred strains between balb/chea and sts/a mice. | to examine the genetic control of acute and late disease induced by a murine coronavirus, strain jhm (jhmv), balb/chea, sts/a, f1 hybrids and 13 recombinant inbred (ri) strains between balb/chea and sts/a mouse strains were inoculated intracerebrally with 100 pfu of jhmv. all the balb/chea mice died within 2 weeks from acute encephalitis. in contrast, sts/a mice were shown to be partially resistant, with a mortality rate of 30%, longer survival times and lower rates of viral production. the mort ... | 1992 | 1316530 |
| molecular cloning and expression of a spike protein of neurovirulent murine coronavirus jhmv variant cl-2. | a cdna encoding the spike (s) protein of the neurovirulent murine coronavirus jhmv variant cl-2 was isolated and sequenced. analysis of the cdna revealed that the s protein consists of 1376 amino acids, as does the s protein of mouse hepatitis virus 4. we inserted the cdna into the genome of vaccinia virus to obtain a recombinant vaccinia virus (rvv). the s protein expressed in rk13 cells infected by the rvv was shown to be electrophoretically and immunologically indistinguishable from the s pro ... | 1992 | 1316938 |
| sequential infection of glial cells by the murine hepatitis virus jhm strain (mhv-4) leads to a characteristic distribution of demyelination. | an antigenic variant of the neurotropic murine coronavirus jhmv, designated 2.2-v-1, causes marked demyelination in the relative absence of encephalitis. it is thus useful for the study of the pathogenesis of demyelinating lesions. to better understand the sequential events leading to demyelination, we have examined murine brain and spinal cord tissue at daily intervals after intracerebral inoculation, evaluating them for the distribution of viral antigen, leukocyte infiltration, and demyelinati ... | 1992 | 1318460 |
| responses of mice to murine coronavirus immunization. | oral and/or intranasal inoculation of susceptible mouse genotypes with the jhm strain of mouse hepatitis virus (mhv-jhm) consistently results in t cell dysfunction as reflected by in vitro proliferative responses to mitogens or allogeneic cells. one approach to examining the mechanism responsible for the observed functional t cell suppression is to determine whether virus replication is required for its induction. to this end, mice were inoculated oronasally with mhv-jhm that was inactivated wit ... | 1992 | 1322658 |
| the fitness of defective interfering murine coronavirus di-a and its derivatives is decreased by nonsense and frameshift mutations. | the genome of the defective interfering (di) mouse hepatitis virus di-a carries a large open reading frame (orf) consisting of orf1a, orf1b, and nucleocapsid sequences. to test whether this fusion orf is important for di virus replication, we constructed derivatives of the di-a genome in which the reading frame was truncated by a nonsense codon or a frameshift mutation. in vitro-transcribed di rnas were transfected into mouse hepatitis virus-infected cells followed by undiluted passage of the re ... | 1992 | 1326650 |
| mouse hepatitis virus utilizes two carcinoembryonic antigens as alternative receptors. | the cellular receptor for the murine coronavirus mouse hepatitis virus (mhv) has been identified as a member of the murine carcinoembryonic antigen (cea) family (r. k. williams, g. s. jiang, and k. v. holmes, proc. natl. acad. sci. usa 88:5533-5536, 1991). however, the receptor protein was not detected in some of the susceptible mouse tissues. we therefore examined whether other types of mhv receptor might exist. by polymerase chain reaction with the conserved sequences of murine cea gene family ... | 1992 | 1326665 |
| immune response to a murine coronavirus: identification of a homing receptor-negative cd4+ t cell subset that responds to viral glycoproteins. | the lymphocyte proliferative response to mouse hepatitis virus, strain jhm (mhv-jhm), a well-described cause of chronic and acute neurological infections, has been studied using vaccinia virus recombinants expressing individual mhv proteins. the surface (s) and transmembrane (m) glycoproteins were the most active proteins in causing proliferation of lymphocytes isolated from immunized adult mice, whereas lymphocytes from persistently infected mice proliferated only in response to the s protein. ... | 1992 | 1347668 |
| cell receptor-independent infection by a neurotropic murine coronavirus. | the cellular receptors for a coronavirus, mouse hepatitis virus (mhv), have been recently identified as one or more members of the carcinoembryonic antigen (cea) family. the neurotropic jhm strain of mhv (mhv-jhm) possesses a highly fusogenic surface (s) glycoprotein. this protein is now shown to promote the spread of mhv into cells lacking the specific cea-related mhv receptor. resistant cells are recruited into mhv-induced syncytium with consequent production of progeny virus. cell-to-cell spr ... | 1992 | 1413526 |
| localization of major neutralizing epitopes on the s1 polypeptide of the murine coronavirus peplomer glycoprotein. | a recombinant baculovirus system has been used to express the amino terminal half of the murine coronavirus (jhmv) peplomer glycoprotein in insect cells. the expressed polypeptide is glycosylated and is recognized by a set of monoclonal antibodies (mabs) specific for jhmv s protein. three of these mabs have a very high neutralizing activity for jhmv but not for other mhv strains. these results indicate that jhmv-specific, major neutralizing epitopes reside in the amino terminal s1 subunit of the ... | 1991 | 1645909 |
| high level transient expression of the murine coronavirus haemagglutinin-esterase. | we have expressed the murine coronavirus haemagglutinin-esterase protein in a vaccinia virus/t7 rna polymerase system. the levels of expression observed are significantly higher than those found in virus-infected cells. the expressed protein has both receptor-destroying (esterase) and receptor-binding (haemadsorption) activities. the use of this system will greatly facilitate analysis of the structure-function relationships of this protein. | 1991 | 1646274 |
| receptor for mouse hepatitis virus is a member of the carcinoembryonic antigen family of glycoproteins. | the receptor for mouse hepatitis virus (mhv), a murine coronavirus, is a 110- to 120-kda glycoprotein on intestinal brush border membranes and hepatocyte membranes. the n-terminal 25-amino acid sequence of immunoaffinity-purified mhv receptor was identical to the predicted mature n termini of two mouse genes related to human carcinoembryonic antigen (cea) and was strongly homologous to the n termini of members of the cea family in humans and rats. polyclonal antibodies to human cea recognized th ... | 1991 | 1648219 |
| mouse hepatitis virus s rna sequence reveals that nonstructural proteins ns4 and ns5a are not essential for murine coronavirus replication. | genes 4 and 5 of mouse hepatitis virus (mhv) are known to encode nonstructural proteins ns4, ns5a, and ns5b, whose function is unknown. in this study, we demonstrated that one of the mhv strains, mhv-s, did not synthesize mrna 4 and made a smaller mrna 5. sequence analysis showed that the transcription initiation site for gene 4 of mhv-s was mutated from the consensus ucuaaac to uuuaaac, consistent with the idea that mutations in this region abolish mrna synthesis. furthermore, within gene 5 the ... | 1991 | 1654456 |
| neurovirulence of six different murine coronavirus jhmv variants for rats. | six variant viruses of the jhmv strain of murine coronavirus with large (cl-2, cnsv, dl and ds) or small (sp-4 and jhm-x) s proteins were compared in terms of their relative neurovirulence in weanling lewis rats. inoculation of various doses of the variants revealed that the cl-2 and cnsv were highly virulent and dl and ds were low-virulent, while sp-4 and jhm-x were avirulent. pathological examination of rats infected with variants cl-2, dl and sp-4 showed that the cl-2 and dl induced severe an ... | 1991 | 1656623 |
| antiidiotypic vaccination against murine coronavirus infection. | rabbit polyclonal antiidiotypic antibodies were generated against a neutralizing mab specific for a conformational epitope on the s glycoprotein of murine hepatitis virus, strain a59 (mhv-a59). these anti-id were directed predominantly against an id that was undetectable in rabbit and rat anti-mhv-a59 sera and weakly represented in syngeneic and allogeneic antiviral sera. however, some partial idiotypic sharing was observed between the id-bearing antibody and a mab with a similar antigenic site ... | 1991 | 1661313 |
| hygromycin b therapy of a murine coronaviral hepatitis. | hepatitis caused by mouse hepatitis virus (mhv-a59), a murine coronavirus, is accompanied by direct infection and replication of virus within the liver. we demonstrate here that the aminoglycoside hygromycin b is able to eliminate mhv-a59 infection from mouse peritoneal macrophages and cultured liver cells in vitro and is also able to reduce levels of virus replication and necrotic liver foci in vivo. | 1991 | 1662025 |
| the role of gamma interferon in infection of susceptible mice with murine coronavirus, mhv-jhm. | infection of balb/c mice with mouse hepatitis virus, strain jhm (mhv-jhm), at any of several intervals relative to ovalbumin (ova) administration resulted in elevated ova-specific igg 2 a titers. since gamma interferon (ifn) has been implicated as an up-regulator of igg 2 a production, attempts were made to determine whether levels of this cytokine were modified in sera of infected mice. serum ifn-gamma was not detected, but treatment of mhv-jhm-infected mice with monoclonal anti-ifn-gamma antib ... | 1991 | 1662041 |
| modulation of coronavirus-mediated cell fusion by homeostatic control of cholesterol and fatty acid metabolism. | cellular susceptibility to fusion mediated by murine coronavirus (mouse hepatitis virus, mhv strain a59) was separated into lipid-dependent and lipid-independent mechanisms with the use of subclones and selected mutants of mouse l-2 fibroblasts. fusion-resistant l-2 cell mutants had similar cholesterol and fatty acid composition as did their fusion-susceptible parent subclone, and were presumably deficient in a genetically mutable non-lipid, host cell factor (e.g., fusion protein receptor). on t ... | 1991 | 1662706 |
| the pathogenic role of virus-specific antibody-secreting cells in the central nervous system of rats with different susceptibility to coronavirus-induced demyelinating encephalitis. | the humoral immune response in the central nervous system (cns) of susceptible lewis (le) rats and resistant brown norway (bn) rats was analysed after intracerebral infection with the murine coronavirus jhm (mhv4). the subclinical course of the infection in bn rats was characterized by an early rise of neutralizing antibodies in the cerebrospinal fluid (csf) 7 days post-infection. at this time in le rats, neutralizing antibodies were not detectable in the csf and the animals developed neurologic ... | 1991 | 1663078 |
| hygromycin b inhibits synthesis of murine coronavirus rna. | the aminoglycoside hygromycin b inhibits the infection of mouse hepatitis virus (mhv) a59 both in vitro and in vivo. in probing the mechanism by which hygromycin b exerts its antiviral effect, we describe here studies which point to inhibition of viral rna synthesis as the key step in virus replication which is affected by the drug. cells which are infected with mhv do not take up higher levels of hygromycin b than do uninfected ones. comparative assays of mhv replication and mhv protein synthes ... | 1991 | 1667257 |
| cloning of the mouse hepatitis virus (mhv) receptor: expression in human and hamster cell lines confers susceptibility to mhv. | the cellular receptor for murine coronavirus mouse hepatitis virus (mhv)-a59 is a member of the carcinoembryonic antigen (cea) family of glycoproteins in the immunoglobulin superfamily. we isolated a cdna clone (mhvr1) encoding the mhv receptor. the sequence of this clone predicts a 424-amino-acid glycoprotein with four immunoglobulinlike domains, a transmembrane domain, and a short intracytoplasmic tail, mhvr1 is closely related to the murine cea-related clone mmcgm1 (mus musculus carcinoembryo ... | 1991 | 1719235 |
| the complete sequence (22 kilobases) of murine coronavirus gene 1 encoding the putative proteases and rna polymerase. | the 5'-most gene, gene 1, of the genome of murine coronavirus, mouse hepatitis virus (mhv), is presumed to encode the viral rna-dependent rna polymerase. we have determined the complete sequence of this gene of the jhm strain by cdna cloning and sequencing. the total length of this gene is 21,798 nucleotides long, which includes two overlapping, large open reading frames. the first open reading frame, orf 1a, is 4488 amino acids long. the second open reading frame, orf 1b, overlaps orf 1a for 75 ... | 1991 | 1846489 |
| monoclonal antibody to the receptor for murine coronavirus mhv-a59 inhibits viral replication in vivo. | because many strains of mouse hepatitis virus (mhv) infect laboratory mice, no effective vaccine has yet been developed. an alternative approach to control mhv disease is the use of a host cell receptor-targeted ligand. to address the potential usefulness of this approach, a monoclonal antibody directed against the host cell receptor for the coronavirus mhv-a59 was administered to infant mice that were then challenged oronasally with 10(4) intracerebral infant mouse median lethal doses of mhv-a5 ... | 1991 | 1849166 |
| localization of extensive deletions in the structural genes of two neurotropic variants of murine coronavirus jhm. | the intracellular rna of two neurotropic variants of the jhm strain of mouse hepatitis virus (mhv) independently isolated from the brain and spinal cord of an infected wistar furth rat were compared with that of the parental virus. the mrnas corresponding to the genes encoding the peplomer (s) and the hemagglutinin-esterase (he) proteins of the variant viruses were found to be smaller in size. the possible sequence changes were studied by oligonucleotide fingerprinting and direct rna sequencing. ... | 1991 | 1850936 |
| ocular tropisms of murine coronavirus (strain jhm) after inoculation by various routes. | the coronavirus mouse hepatitis virus (mhv, strain jhm) infects tissues in the anterior and posterior segments when injected intravitreally into adult mouse eyes. infection causes progressive damage to the photoreceptors and retinal pigment epithelium (rpe), resulting in a disease the authors have termed jhm retinopathy. to determine whether this virus is retinotropic independent of route of inoculation, the authors injected mice with virus by several different routes: into the anterior chamber ... | 1991 | 1851734 |
| expression of the spike protein of murine coronavirus jhm using a baculovirus vector. | the spike (s) protein of murine coronavirus jhm strain (jhmv) has been expressed in insect cells using a recombinant baculovirus vector. the expressed s protein was shown to be glycosylated and expressed on the cell surface, and to be similar in size and antigenic properties to the s protein produced in mouse cells infected by jhmv. however, no proteolytic cleavage was detected in insect cells. the sera from rats immunised with s protein derived from insect cells reacted in immunoprecipitation a ... | 1990 | 1966405 |
| murine coronavirus gene 1 polyprotein contains an autoproteolytic activity. | the 5' most gene of the murine coronavirus genome, gene 1, is presumed to encode the viral rna-dependent rna polymerase. cdna clones representing this gene encompass more than 22 kilobases, suggesting that this region may encode multifunctional polyprotein(s). it has previously been shown that the n-terminal portion of this gene product is cleaved into a protein of 28 kilodaltons (p28). to identify possible functional domains of gene 1 and further understand the mechanism of synthesis of the p28 ... | 1990 | 1966414 |
| identification of polypeptides encoded in open reading frame 1b of the putative polymerase gene of the murine coronavirus mouse hepatitis virus a59. | the polypeptides encoded in open reading frame (orf) 1b of the mouse hepatitis virus a59 putative polymerase gene of rna 1 were identified in the products of in vitro translation of genome rna. two antisera directed against fusion proteins containing sequences encoded in portions of the 3'-terminal 2.0 kb of orf 1b were used to immunoprecipitate p90, p74, p53, p44, and p32 polypeptides. these polypeptides were clearly different in electrophoretic mobility, antiserum reactivity, and partial prote ... | 1991 | 2033667 |
| identification of the spinal cord as a major site of persistence during chronic infection with a murine coronavirus. | after intranasal inoculation, mouse hepatitis virus (mhv) gains entry into the central nervous system (cns) via the olfactory and trigeminal nerves. under the appropriate conditions, some mice develop clinically apparent demyelinating encephalomyelitis several weeks later, with virus always present in the spinal cord. to determine the pathway by which virus reaches the cord, brains and spinal cords of infected, asymptomatic mice were analyzed by in situ hybridization. viral rna was always detect ... | 1990 | 2158180 |
| murine coronavirus induces an acute and long-lasting disease of the retina. | the ability of the coronavirus mouse hepatitis virus, strain jhm, to grow in the retinas of balb/c mice was examined. inoculation into the vitreous chamber produced significant changes. immunoperoxidase staining of frozen sections with either monoclonal or polyclonal antiserum revealed coronaviral antigens in the iris, ciliary body, and a few ganglion cells on day 1. the retinal pigment epithelial cells began expressing viral antigen on day 2 and large amounts of antigen were present in these ce ... | 1990 | 2159082 |
| the primary structure and expression of the second open reading frame of the polymerase gene of the coronavirus mhv-a59; a highly conserved polymerase is expressed by an efficient ribosomal frameshifting mechanism. | sequence analysis of a substantial part of the polymerase gene of the murine coronavirus mhv-a59 revealed the 3' end of an open reading frame (orf1a) overlapping with a large orf (orf1b; 2733 amino acids) which covers the 3' half of the polymerase gene. the expression of orf1b occurs by a ribosomal frameshifting mechanism since the orf1a/orf1b overlapping nucleotide sequence is capable of inducing ribosomal frameshifting in vitro as well as in vivo. a stem-loop structure and a pseudoknot are pre ... | 1990 | 2159623 |
| establishing a genetic recombination map for murine coronavirus strain a59 complementation groups. | mhv-a59 temperature-sensitive mutants, representing one rna+ and five rna- complementation groups, were isolated and characterized by genetic recombination techniques. maximum recombination frequencies occurred under multiplicities of infection greater than 10 each in which 99.99% of the cells were co-infected. recombination frequencies between different ts mutants increased steadily during infection and peaked late in the virus growth cycle. these data suggest that recombination is a late event ... | 1990 | 2164728 |
| murine coronavirus nonstructural protein ns2 is not essential for virus replication in transformed cells. | two isolates of the murine hepatitis virus (mhv) strain jhm, which differed in their ability to express the nonstructural gene product ns2, were characterized. the mhv wb3 isolate encodes a 30,000-molecular-weight ns2 protein that can be readily detected in infected cells by using a specific monoclonal antibody, mab 2a. the mhv wb1 isolate is a deletion mutant that lacks a functional ns2 gene and the transcriptional signals required for the synthesis of an ns2 mrna. however, there are no obvious ... | 1990 | 2168966 |
| analysis of efficiently packaged defective interfering rnas of murine coronavirus: localization of a possible rna-packaging signal. | we have previously shown that most of the defective interfering (di) rna of mouse hepatitis virus (mhv) are not packaged into virions. we have now identified, after 21 serial undiluted passages of mhv, a small di rna, dissf, which is efficiently packaged into virions. the dissf rna replicated at a high efficiency on its transfection into the helper virus-infected cells. the virus released from the transfected cells interfered strongly with mrna synthesis and growth of helper virus. cdna cloning ... | 1990 | 2243386 |
| characterization of the structural proteins of the murine coronavirus strain a59 using monoclonal antibodies. | monoclonal antibodies reacting with the a59 strain of mouse hepatitis virus (mhv-a59) were characterized and those specific to the e2 major envelope glycoprotein were studied in detail. antibodies were tested for their ability to neutralize viral infectivity (n+ characteristic) and prevent viral-induced cell-to-cell fusion (f+ characteristic). all four possible combinations of activities reflecting e2 functions were found, i.e., n+f+, n-f-, n+f-, and n-f+. in addition, competitive binding studie ... | 1987 | 2437592 |
| comparative analysis of coronavirus jhm-induced demyelinating encephalomyelitis in lewis and brown norway rats. | lewis and brown norway rats were infected at different ages with the neurotropic murine coronavirus strain, jhm and the resultant central nervous system diseases were studied. suckling rats of both strains came down with a fatal, acute encephalomyelitis. weanling lewis rats developed a subacute demyelinating encephalomyelitis which neuropathologically revealed changes of an immunopathologic reaction. in contrast, brown norway rats developed a clinically silent subacute demyelinating encephalomye ... | 1987 | 2444766 |
| growth of a murine coronavirus in a microcarrier cell culture system. | the growth of the murine coronavirus mhv-a59 on murine dbt cells adapted to dextran-made cytodex 1 microcarriers was studied in comparison with cells grown on plastic dishes. with a microcarrier concentration of 5 g/l in spinner flasks, a density of 3 x 10(6) cells/ml was reached in 7 days. under these conditions, cells supported virus growth to the same extent as when they were grown on the plastic substratum. this was shown by a similar development of virus-induced syncytia, the release of an ... | 1989 | 2476458 |
| comparison of six different murine coronavirus jhm variants by monoclonal antibodies against the e2 glycoprotein. | we have examined six different jhmv variants, sp-4 (recloned wt jhmv), cl-2, cnsv, dl, ds, and jhm-x, in terms of the sizes of the mrna3 and e2 glycoprotein as well as their reactivity to a panel of monoclonal antibodies to the e2 glycoprotein. two of these variants, sp-4 and jhm-x, were found to have smaller mrna3 and e2 glycoprotein species compared with those of the other four variants. in addition, sp-4 and jhm-x were distinguished from the other four variants by their inability to bind to m ... | 1989 | 2538034 |
| hemagglutination by murine hepatitis viruses. absence of detectable activity in strains 3, a59, and s grown on dbt cells. | erythrocytes from twelve mammalian and avian sources in ten different buffers at three incubation temperatures could not be hemagglutinated with murine hepatitis virus (mhv) strains 3, a59, or s grown on dbt cells. viral antigen preparation in the absence of fetal calf serum, partial virus purification, or various concentrations of red blood cells still failed to yield detectable hemagglutinating activity. thus, the newly described mhv-dvim remains the only hemagglutinating strain of murine coro ... | 1989 | 2542182 |
| spread of a neurotropic murine coronavirus into the cns via the trigeminal and olfactory nerves. | the route of entry into the central nervous system (cns) of most neurtropic viruses has not been established. the coronavirus, mouse hepatitis virus strain jhm (mhv-jhm), causes acute encephalomyelitis and acute and chronic demyelinating diseases and is an important model system for virus-induced neurological disease. suckling c57bl/6 mice infected intranasally with mhv-jhm develop either the acute encephalomyelitis or a late onset, symptomatic demyelinating encephalomyelitis, depending on wheth ... | 1989 | 2543129 |
| a model for persistent murine coronavirus infection involving maintenance via cytopathically infected cell centres. | the relatively cell impermeable hygromycin b was found to inhibit viral but not cellular protein synthesis when added to cultures of murine hepatitis virus (mhv)-infected or mock-infected mouse l-2 fibroblasts. membrane permeability, as judged by influx of sodium ions, has previously been demonstrated to be an mhv e2 glycoprotein-mediated, cytopathic effect of mhv infection in l-2 cells. it is therefore likely that the selective effect of hygromycin b on viral protein synthesis is a reflection o ... | 1989 | 2543759 |
| several rat cell lines share a common defect in their inability to internalize murine coronaviruses efficiently. | infection of rat cells, schwannoma rn2, hepatoma htc or myoblast l6, with the murine coronavirus jhm strain results in a persistent infection characterized by the release of virus over an extended period of time with a limited cytopathology. several stages of the viral replication cycle have been examined in these cells in comparison to those in mouse l2 cells, which are totally permissive to jhm infection. although the rat cells bound as much virus as the mouse cells. their ability to internali ... | 1989 | 2544662 |
| identification of a domain required for autoproteolytic cleavage of murine coronavirus gene a polyprotein. | the 5'-most gene of the murine coronavirus genome, gene a, is presumed to encode viral rna-dependent rna polymerase. it has previously been shown that the n-terminal portion of this gene product is cleaved into a protein of 28 kilodaltons (p28). to further understand the mechanism of synthesis of the p28 protein, cdna clones representing the 5'-most 5.3 kilobases of murine coronavirus mouse hepatitis virus strain jhm were sequenced and subcloned into pt7 vectors from which rnas were transcribed ... | 1989 | 2547993 |
| identification of a new transcriptional initiation site and the corresponding functional gene 2b in the murine coronavirus rna genome. | we have previously shown that some strains of the murine coronavirus mouse hepatitis virus (mhv) synthesize an additional mrna species (mrna 2b, previously called mrna 2a) with a size intermediate between that of mrnas 2 and 3, suggesting the presence of an optional transcriptional initiation site. this transcriptional start is dependent on the leader sequence of the virus strains. to study the mechanism of coronavirus transcriptional regulation, we have cloned and sequenced the region of the vi ... | 1989 | 2547994 |
| inhibition of murine coronavirus rna synthesis by hydroxyguanidine derivatives. | a series of hydroxyguanidine derivatives, which are substituted salicylaldehyde schiff-bases of 1-amino-3- hydroxyguanidine tosylate, were tested for the inhibition of rna synthesis of mouse hepatitis virus (mhv). it was shown that these compounds could selectively inhibit virus-specific rna synthesis. every aspect of viral rna synthesis, including synthesis of negative-stranded rna, subgenomic mrna transcription and genomic rna replication, was inhibited to roughly the same extent. these compou ... | 1989 | 2554614 |
| expression of the peplomer glycoprotein of murine coronavirus jhm using a baculovirus vector. | the gene encoding the e2 peplomer glycoprotein of coronavirus mouse hepatitis virus jhm strain (jhmv) has been inserted into the genome of autographa californica nuclear polyhedrosis baculovirus (acnpv) in lieu of the coding region of the acnpv polyhedrin gene. this recombinant virus produced e2 protein in insect cells under the control of the baculovirus polyhedrin promotor. the expressed e2 protein was shown in size and antigenic properties to be similar to the e2 protein produced in mouse cel ... | 1989 | 2556844 |
| biosynthesis, structure, and biological activities of envelope protein gp65 of murine coronavirus. | we have previously shown that gp65 (e3) is a virion structural protein which varies widely in quantity among different strains of mouse hepatitis virus (mhv). in this study, the biosynthetic pathway and possible biological activities of this protein were examined. the glycosylation of gp65 in virus-infected cells was inhibited by tunicamycin but not by monensin, suggesting that it contains an n-glycosidic linkage. glycosylation is cotranslational and appears to be complete before the glycoprotei ... | 1989 | 2556847 |
| sequence and translation of the murine coronavirus 5'-end genomic rna reveals the n-terminal structure of the putative rna polymerase. | a 28-kilodalton protein has been suggested to be the amino-terminal protein cleavage product of the putative coronavirus rna polymerase (gene a) (m.r. denison and s. perlman, virology 157:565-568, 1987). to elucidate the structure and mechanism of synthesis of this protein, the nucleotide sequence of the 5' 2.0 kilobases of the coronavirus mouse hepatitis virus strain jhm genome was determined. this sequence contains a single, long open reading frame and predicts a highly basic amino-terminal re ... | 1987 | 2824826 |
| limbic encephalitis after inhalation of a murine coronavirus. | the spread of a neurotropic coronavirus, mouse hepatitis virus strain a59, in the mouse central nervous system was studied after intranasal inoculation. mouse hepatitis virus strain a59 spread during the 3- to 5-day postinoculation period, through the olfactory pathway into the limbic system. coronavirus particles were detected in the limbic system by electron microscopy. the combination of temporal propagation through an anatomical-physiological central nervous system pathway and anatomical res ... | 1988 | 2826881 |
| defective-interfering particles of murine coronavirus: mechanism of synthesis of defective viral rnas. | the mechanism of synthesis of the defective viral rnas in cells infected with defective-interfering (di) particles of mouse hepatitis virus was studied. two di-specific rna species, dissa of genomic size and disse of subgenomic size, were detected in di-infected cells. purified di particles, however, were found to contain predominantly dissa and only a trace amount of disse rna. despite its negligible amount, the disse rna in virions appears to serve as the template for the synthesis of disse rn ... | 1988 | 2831651 |
| in vivo rna-rna recombination of coronavirus in mouse brain. | rna-rna recombination between different strains of the murine coronavirus mouse hepatitis virus (mhv) occurs at a very high frequency in tissue culture. to demonstrate that rna recombination may play a role in the evolution and pathogenesis of coronaviruses, we sought to determine whether mhv recombination could occur during replication in the animal host of the virus. by using two selectable markers, i.e., temperature sensitivity and monoclonal antibody neutralization, we isolated several recom ... | 1988 | 2833625 |
| detection of a murine coronavirus nonstructural protein encoded in a downstream open reading frame. | mouse hepatitis virus (mhv) gene 5 contains two open reading frames. we have expressed the second open reading frame of this gene (gene 5 orf 2) in an escherichia coli expression system. this system utilized a plasmid which contained the promoter and the first 36 codons of the reca gene fused in frame with the mhv gene 5 orf 2, which is fused in turn to the beta-galactosidase gene. the protein product of this gene fusion was used to raise antibody to gene 5 orf 2. the specificity of the antibody ... | 1988 | 2834866 |
| rna recombination of murine coronaviruses: recombination between fusion-positive mouse hepatitis virus a59 and fusion-negative mouse hepatitis virus 2. | it has previously been shown that the murine coronavirus mouse hepatitis virus (mhv) undergoes rna recombination at a relatively high frequency in both tissue culture and infected animals. thus far, all of the recombination sites had been localized at the 5' half of the rna genome. we have now performed a cross between mhv-2, a fusion-negative murine coronavirus, and a temperature-sensitive mutant of the a59 strain of mhv, which is fusion positive at the permissive temperature. by selecting fusi ... | 1988 | 2835504 |
| synthesis of virus-specific rna in permeabilized murine coronavirus-infected cells. | we have developed a permeabilized cell system for assaying mouse hepatitis virus-specific rna polymerase activity. this activity was characterized as to its requirements for mono- and divalent cations, requirements for an exogenous energy source, and ph optimum. this system faithfully reflects mhv-specific rna synthesis in the intact cell, with regard to both its time of appearance during the course of infection and the products synthesized. the system is efficient and the rna products were iden ... | 1988 | 2842958 |
| reactivities of 4 murine coronavirus antigens with immunized or naturally infected rat sera by enzyme linked immunosorbent assay. | four murine coronavirus antigens, sialodacryoadenitis virus (sdav) strain tg, parker's rat coronavirus (pcv) strain 8190, mouse hepatitis virus (mhv) strains s and nuu, were examined for their reactivities to hyperimmunized and naturally infected rat sera by elisa. with the immunized sera, sdav and pcv antigens reacted best with respective homologous sera. mhv antigens reacted with all antisera, anti-sdav, anti-pcv, and anti-mhv-s at approximately the same level, and mhv-s showed a slightly high ... | 1988 | 2843391 |
| regional localization of virus in the central nervous system of mice persistently infected with murine coronavirus jhm. | suckling c57bl/6 mice infected with mouse hepatitis virus strain jhm (mhv-jhm) develop either a fatal acute encephalomyelitis or a late onset demyelinating disease, depending on whether they are nursed by unimmunized or immunized dams. to determine the localization of virus-specific rna, serial sections of brains from infected and uninfected mice were annealed with a 35s-labeled antisense rna probe and analyzed by film autoradiography. in the mice with acute encephalomyelitis, viral rna was pres ... | 1988 | 2845647 |
| primary structure and translation of a defective interfering rna of murine coronavirus. | an intracellular defective-interfering (di) rna, disse, of mouse hepatitis virus (mhv) obtained after serial high multiplicity passage of the virus was cloned and sequenced. disse rna is composed of three noncontiguous genomic regions, representing the first 864 nucleotides of the 5' end, an internal 748 nucleotides of the polymerase gene, and 601 nucleotides from the 3' end of the parental mhv genome. the disse sequence contains one large continuous open reading frame. two protein products from ... | 1988 | 2845661 |
| characterization of a variant virus selected in rat brains after infection by coronavirus mouse hepatitis virus jhm. | the intracerebral inoculation of lewis rats with the murine coronavirus mhv-jhm leads in the majority of animals to acute encephalitis and death within 14 days. viral rnas isolated from the brains of animals 5 to 7 days after infection were compared by northern blot analysis with the rnas produced during the lytic infection of sac(-) or dbt cells with wild-type mhv-jhm (wt virus). reproducibly, the subgenomic mrnas 2 and 3 but no other viral rnas were significantly larger in the brain-derived ma ... | 1985 | 2985806 |
| infection of the basal ganglia by a murine coronavirus. | the coronavirus, mouse hepatitis virus strain a59 (mhv-a59), causes mild encephalitis and chronic demyelination. immunohistochemical techniques showed that mhv-a59-infected c57bl/6 mice contained dense deposits of viral antigen in the subthalamic nucleus and substantia nigra, with fewer signs of infection in other regions of the brain. the animals showed extra- and intracellular vacuolation, neuronal loss, and gliosis in the subthalamic-nigral region. such localization is unprecedented among kno ... | 1985 | 2992088 |
| characterization of leader-related small rnas in coronavirus-infected cells: further evidence for leader-primed mechanism of transcription. | mouse hepatitis virus (mhv), a murine coronavirus, replicates in the cytoplasm and synthesizes 7 viral mrnas containing an identical stretch of leader rna sequences at the 5'-end of each rna. the leader-coding sequences at the 5'-end of genomic rna are at least 72 nucleotides in length and are joined to the viral mrnas by a unique mechanism. utilizing a leader-specific cdna probe, we have detected several free leader rna species ranging from 70 to 82 nucleotides in length. the predominant leader ... | 1985 | 2992183 |
| attenuation of murine coronavirus infection by ammonium chloride. | ammonium chloride at a concentration of 20 mm delayed by 4-5 hr the production of virus progeny in mouse l-2 cells infected at high multiplicity with mouse hepatitis virus (mhv). this delay was seen in the production of both intracellular and extracellular virus. however, the final titers were similar to those produced by mhv-infected cells maintained in normal medium. the manifestation of virus-induced cell fusion was similarly found to be delayed, but not otherwise decreased in severity, when ... | 1985 | 2997991 |
| proteolytic cleavage of the e2 glycoprotein of murine coronavirus: activation of cell-fusing activity of virions by trypsin and separation of two different 90k cleavage fragments. | in the murine coronavirus mouse hepatitis virus, a single glycoprotein, e2, is required both for attachment to cells and for cell fusion. cell fusion induced by infection with mouse hepatitis virus strain a59 was inhibited by the addition of monospecific anti-e2 antibody after virus adsorption and penetration. adsorption of concentrated coronavirions to uninfected cells did not cause cell fusion in the presence of cycloheximide. thus, cell fusion was induced by e2 on the plasma membrane of infec ... | 1985 | 2999443 |
| proteolytic cleavage of the e2 glycoprotein of murine coronavirus: host-dependent differences in proteolytic cleavage and cell fusion. | cell fusion induced by infection with mouse hepatitis virus strain a59 (mhv-a59) varied markedly in extent and time course in four different murine cell lines. when inoculated at a multiplicity of 3 to 5 pfu per cell, the sac-, l2, and dbt cell lines began to fuse by 7 h, were fused into confluent syncytia by 9 to 12 h, and peeled from the substrate by 10 to 14 h. these virulent virus-cell interactions were in striking contrast to the moderate interaction of mhv-a59 with the 17 cl 1 cell line, i ... | 1985 | 2999444 |
| natural cytotoxicity against mouse hepatitis virus-infected target cells. i. correlation of cytotoxicity with virus binding to leukocytes. | spleen cells from uninfected control mice selectively lysed balb/c 3t3 fibroblasts infected with mouse hepatitis virus (mhv), a murine coronavirus. lysis of infected cells occurred within 3 hr, and histocompatibility between effector and target cells was not required. this natural, cell-mediated, virus-associated cytotoxicity differed from nk cell- and t cell-mediated lysis. spleen cells from animals infected with mhv were enriched in nk activity and were more cytotoxic to yac-1 target cells, bu ... | 1986 | 3003198 |
| intraepithelial leukocytes contain a unique subpopulation of nk-like cytotoxic cells active in the defense of gut epithelium to enteric murine coronavirus. | initially the intraepithelial leukocytes (iel) of specific pathogen free (spf) mice were compared with those of mice held without isolation and were found to differ markedly in total number and distribution of cell surface antigens. the iel from spf mice expressed significantly less thy-1, lyt-1, and lyt-2 antigens than their conventional counterparts. the local cell-mediated immune response of mucosal lymphocytes to an enteric murine coronavirus (mhv-y) was studied in inbred strains of naive sp ... | 1986 | 3005395 |
| the organ tropism of mouse hepatitis virus a59 in mice is dependent on dose and route of inoculation. | the organ tropism of mhv-a59, a murine coronavirus, was studied in 4-6 week-old c57bl/6 mice inoculated by different routes and with various amounts of virus. mhv-a59 caused hepatitis after intracerebral and intraperitoneal inoculation (two clearly artificial routes) and also after intranasal and intragastric inoculation (two routes more likely to mimic naturally acquired infection). for each route, the severity of hepatitis was dependent on the amount of virus inoculated. significantly higher d ... | 1986 | 3009966 |
| leader sequences of murine coronavirus mrnas can be freely reassorted: evidence for the role of free leader rna in transcription. | mouse hepatitis virus (mhv), which replicates in cytoplasm of infected cells, contains an identical leader rna sequence at the 5' end of each of the virus-specific mrnas. previous studies suggested that the synthesis of these mrnas does not involve conventional rna splicing and may instead require priming by a free leader rna. in this communication, we demonstrate that, during a mixed infection with two different mhvs, the leader rna sequences from one virus could be detected on the mrnas of the ... | 1986 | 3012558 |
| analysis of jhm central nervous system infections in rats. | intracerebral inoculation of murine coronavirus jhm into 2- to 3-day-old wistar furth rats causes an acute encephalomyelitis, while inoculations at 10 days of age usually result in hind leg paralysis. to examine the distribution of viral antigens within this infected central nervous system (cns) tissue, we used the avidin-biotin-peroxidase method to detect monoclonal and polyclonal antibodies bound to jhm structural proteins; in addition we used the western blot technique to detect viral protein ... | 1986 | 3015091 |
| murine coronavirus-induced encephalomyelitis in rats: analysis of immunoglobulins and virus-specific antibodies in serum and cerebrospinal fluid. | the humoral intrathecal immune response in coronavirus-induced demyelinating encephalomyelitis in rats associated with an autoimmune reaction to brain antigen, was analysed. the csf of these animals revealed immune reactions which were directed against coronavirus and other, unknown, antigens. in general, no direct correlation between the disease, the state of the blood-brain barrier (bbb), intrathecal synthesis of ig and the presence of virus-specific antibodies was detectable, suggesting that ... | 1986 | 3016024 |
| site-specific alteration of murine hepatitis virus type 4 peplomer glycoprotein e2 results in reduced neurovirulence. | strains of the murine coronavirus mouse hepatitis virus type 4 (mhv-4) which contained a mutation in the e2 peplomer glycoprotein were obtained by selection for resistance to neutralization by monoclonal antibodies. characterization of six variants representing two independent epitopes on e2, e2b and e2c, by in vitro neutralization and antibody-binding assays demonstrated that selection for an alteration in epitope e2b also resulted in changes in epitope e2c and vice versa. we observed a mutatio ... | 1986 | 3016306 |
| genetic resistance to mouse hepatitis virus correlates with absence of virus-binding activity on target tissues. | the molecular mechanism of genetic resistance of inbred mouse strains to mouse hepatitis virus, a murine coronavirus, was studied by comparing virus binding to plasma membranes of intestinal epithelium or liver from susceptible balb/c and resistant sjl/j mice with a new solid-phase assay for virus-binding activity. virus bound to isolated membranes from susceptible mice, but not to membranes from resistant mice. f1 progeny of sjl/j x balb/c mice had an intermediate level of virus-binding activit ... | 1987 | 3023696 |
| the 5'-end sequence of the murine coronavirus genome: implications for multiple fusion sites in leader-primed transcription. | the coronavirus leader-primed transcription model proposes that free leader rna species derived from the 5'-end of the genomic rna are utilized as a primer for the transcription of subgenomic mrnas. to elucidate the precise mechanism of leader-priming, we cloned and sequenced the 5'-end of the mouse hepatitis virus genomic rna. the 5'-terminal sequences are identical to the leader sequences present at the 5'-end of the subgenomic mrnas. two possible hairpin loop structures and an au-rich region ... | 1987 | 3027981 |
| multiple recombination sites at the 5'-end of murine coronavirus rna. | mouse hepatitis virus (mhv), a murine coronavirus, contains a nonsegmented rna genome. we have previously shown that mhv could undergo rna-rna recombination in crosses between temperature-sensitive mutants and wild-type viruses at a very high frequency (s. makino, j.g. keck, s.a. stohlman, and m.m.c. lai (1986) j. virol. 57, 729-737). to better define the mechanism of rna recombination, we have performed additional crosses involving different sets of mhv strains. three or possibly four classes o ... | 1987 | 3027982 |
| identification of putative polymerase gene product in cells infected with murine coronavirus a59. | the virion rna of mouse hepatitis virus, strain a59 (mhv-a59) is believed to be the mrna for the viral rna-dependent rna polymerase. the cell-free translation of virion rna results in the synthesis of two predominant products p220 and p28 (m. r. denison and s. perlman, 1986, j. virol. 60, 12-18). p28 is a basic protein and is readily detected by two-dimensional gel electrophoresis. when infected cells and isolated virions were assayed for this protein by two-dimensional gel electrophoresis, p28 ... | 1987 | 3029990 |
| analysis of the intrathecal humoral immune response in brown norway (bn) rats, infected with the murine coronavirus jhm. | serum and csf specimens from clinically healthy brown norway (bn) rats inoculated intracerebrally with corona virus jhm were analysed with respect to the state of the blood-brain barrier (bbb) and the intrathecal synthesis and isoelectric distribution of immunoglobulins (ig). increased csf/serum ratios for ig in the context of an intact bbb were never seen in the absence of intrathecal synthesis of virus-specific antibodies. affinity-mediated immunoblot analysis revealed a broad pattern of virus ... | 1987 | 3031130 |
| rat glial c6 cells are defective in murine coronavirus internalization. | rat c6 glial cells were resistant to infection by several strains of murine coronaviruses. the restriction was not at the adsorption stage, since virus adsorbed to the c6 cells in a similar manner to mouse l cells which supported a lytic infection. the virus could not be internalized by the c6 cells. however, if the virus was introduced into the c6 cells by polyethylene glycol fusion, viral replication occurred and progeny virions were released from the infected cells. these studies indicated th ... | 1987 | 3035065 |
| inducibility of ia antigen on astrocytes by murine coronavirus jhm is rat strain dependent. | inducibility of ia molecules on cultivated astrocytes by jhm virus correlates with demyelinating disease susceptibility of animals from which these astrocytes are derived. on the contrary, class i induction of both astrocytes and oligodendrocytes occurs as a consequence of normal cultivation procedures in both susceptible and resistant strains. increased expression of class i antigens on rat astrocytes and oligodendrocytes is not related to jhm viral infection as it is in the mouse. these data i ... | 1987 | 3036995 |
| rna-binding proteins of coronavirus mhv: detection of monomeric and multimeric n protein with an rna overlay-protein blot assay. | rna-binding proteins of coronavirus mhv-a59 were identified using an rna overlay-protein blot assay (ropba). the major viral rna-binding protein in virions and infected cells was the phosphorylated nucleocapsid protein n (50k). a new 140k virus structural protein was identified as a minor rna-binding protein both in virions and in infected cells. the 140k protein was antigenically related to n, and upon reduction, yielded only 50k n. thus, the 140k protein is probably a trimer of n subunits link ... | 1986 | 3083580 |
| structural polypeptides of the murine coronavirus dvim. | the structural polypeptides of the murine coronavirus dvim (diarrhoea virus of infant mice) have been analysed in comparison with other strains mhv-2, mhv-3, mhv-4 (jhm) and mhv-s by sds-page. in the presence of 2-mercaptoethanol, three major glycopolypeptides, gp180, gp69, gp25 (as a group of similar species) and one major non-glycosylated polypeptide p58 were detected. the gp69 is a dvim specific glycopolypeptide, in which the glycosidic moieties are linked to the core polypeptide through n-gl ... | 1986 | 3718235 |
| enhanced growth of a murine coronavirus in transformed mouse cells. | plaque formation by a59 virus, a murine coronavirus, was facilitated in al/n and balb mouse cells transformed by polyoma virus, simian virus 40, murine sarcoma virus, or mammary tumor virus. in these virus-transformed cells, a59 virus plaques were larger, they appeared earlier, and plaquing efficiencies were higher than in normal, untransformed cells. "spontaneously" transformed al/n cells behaved similarly to untransformed cells, whereas "spontaneously" transformed balb cells resembled virus-tr ... | 1972 | 4564284 |
| relapsing subacute demyelinating encephalomyelitis in rats during the course of coronavirus jhm infection. | temperature-sensitive mutants of the murine coronavirus jhm induced a subacute demyelinating encephalomyelitis (sde) in young rats. neurological symptoms were associated with marked lesions of primary demyelination in the white matter of the central nervous system (cns), and developing after an incubation time of several weeks to months. many rats survived this infection and recovered completely from this cns disease. among 43 survivors of sde, 9 rats developed a relapse 27-153 days after onset ... | 1984 | 6086712 |
| characterization of murine coronavirus rna by hybridization with virus-specific cdna probes. | genome rna of mouse hepatitis virus (mhv) strain a59 has been used as a template to synthesize two virus-specific probes: cdnarep, representing the majority of sequences of the genome rna and cdna3', representing the 3' end of the genome rna. molecular hybridization with these cdnas was used to characterize both genome rna and intracellular virus-specific rnas. hybridization of genome rnas of mhv strains a59, jhm, and mhv-3 with a59 cdnarep showed that, although these three strains exhibit diffe ... | 1983 | 6185631 |
| synthesis and subcellular localization of the murine coronavirus nucleocapsid protein. | the synthesis and processing of the nucleocapsid protein (pp60) of the jhm strain of murine coronaviruses were examined. pulse-chase experiments showed that pp60 was synthesized initially as a protein of approximately 57,000 in molecular weight (p57). immunoprecipitation using mouse anti-jhmv antiserum indicated that p57 was virus specific. immunoprecipitation with monoclonal antibodies specific for pp60 showed that p57 was antigenically related to pp60 and was not phosphorylated, while the intr ... | 1983 | 6196910 |
| hybridoma antibodies to the murine coronavirus jhm: characterization of epitopes on the peplomer protein (e2). | a panel of hybridoma antibodies that react with the surface peplomer glycoprotein (e2) of the murine coronavirus jhm were produced to characterize major antigenic domains associated with functions related to virulence. three groups of hybridoma antibodies were differentiated by immunoprecipitation of lysates from jhm-infected cells. one group precipitated the virion structural proteins gp170 and gp98 together with the intracellular form of e2, gp150. a second group reacted with gp98 and gp150, a ... | 1984 | 6209363 |
| genetic variation of neurotropic and non-neurotropic murine coronaviruses. | the murine coronavirus strains mhv jmh, mhv 1, mhv 2, mhv 3 and mhv a 59 were tested for their neurovirulence in weanling rats. the strain jhm was found to be highly neurovirulent for weanling rats, whereas the other strains were not, or only slightly, neurovirulent. mhv 1 caused no lesions in weanling rats. the other strains (mhv 2, mhv 3 and mvh a59) induced predominantly subclinical infections in weanling rats as demonstrated by an increase of antibodies and inflammatory lesions in the liver. ... | 1981 | 6270248 |
| jhm infections in rats as a model for acute and subacute demyelinating disease. | an animal model with different central nervous system (cns) disease processes associated with demyelination is described which provides a basis to analyse the pathogenetic mechanisms leading to these disorders. intracerebral infection of rats with the murine coronavirus strain jhm can result in an acute encephalomyelitis with a short incubation period or in subacute to chronic encephalomyelitis occurring after prolonged incubation. the most prominent finding of the latter two diseases consists o ... | 1981 | 6278889 |
| coronavirus 229e susceptibility in man-mouse hybrids is located on human chromosome 15. | human coronavirus 229e, n enveloped, rna-containing virus, causes respiratory illness in man and is serologically related to murine coronavirus jhm, which causes acute and chronic demyelination in rodents. 229e displays a species-specific host range restriction whose genetic basis was studied in human-mouse hybrids. 229e replicated in human wi-38 cells but not in three mouse cell lines tested (rag, lm/tk-, and a9). human coronavirus sensitivity (hcvs) was expressed as a dominant phenotype in hyb ... | 1982 | 6285532 |
| cell-free translation of murine coronavirus rna. | the coding assignments of the intracellular murine hepatitis virus-specific subgenomic rna species and murine hepatitis virion rna have been investigated by cell-free translation. the six murine hepatitis virus-specific subgenomic rnas were partially purified by agarose gel electrophoresis and translated in an mrna-dependent rabbit reticulocyte lysate, and the cell-free translation products were characterized by gel electrophoresis, immunoprecipitation, and tryptic peptide mapping. these studies ... | 1982 | 6292469 |
| neurovirulence of murine coronavirus jhm temperature-sensitive mutants in rats. | the murine coronavirus strain jhm is highly neurotropic in rats and has a marked tendency to cause demyelinating central nervous system diseases after intracerebral inoculation. the clinical diseases observed range from an acute encephalomyelitis occurring within 2 weeks postinfection to a subacute demyelinating encephalomyelitis developing several weeks or months postinfection. uncloned wild-type virus induced both acute and subacute diseases, whereas cloned jhm virus grown in tissue culture ca ... | 1983 | 6301992 |
| adoptive transfer of eae-like lesions from rats with coronavirus-induced demyelinating encephalomyelitis. | viruses have been found to induce inflammatory demyelinating lesions in central nervous system (cns) tissue of both animal and man, either by natural infections or after vaccination. at least two different pathogenic mechanisms have been proposed for these changes, a cytopathic viral infection of oligodendroglia cells with subsequent cell death, and a host immune reaction against virus and brain antigens. we now report the occurrence of cell-mediated immune reactions against basic myelin protein ... | 1983 | 6310411 |
| antigenic relationships of murine coronaviruses: analysis using monoclonal antibodies to jhm (mhv-4) virus. | monoclonal antibodies were produced to jhmv-dl, a neurotropic member of the mouse hepatitis virus (mhv) or murine coronavirus group. of 23 antibodies isolated, 10 were specific for the major envelope glycoprotein, gp180/90, 10 for the nucleocapsid protein, pp60, and 3 for the minor envelope glycoprotein, gp25. eleven different mhv isolates were used in antibody binding assays to study antigenic relationships among the viruses. each mhv isolate tested had a unique pattern of antibody binding, ind ... | 1983 | 6318433 |
| experimental demyelination produced by the a59 strain of mouse hepatitis virus. | intracerebral inoculation of 4- to 6-week-old c57bl/6 mice with the a59 strain of mouse hepatitis virus (mhv), a murine coronavirus, produced biphasic disease. acute hepatitis and mild meningoencephalitis were followed by subacute spastic paralysis with demyelinating lesions in the brain and spinal cord as determined by epon-embedded toluidine-blue-stained sections and by electronmicroscopy. mhv-a59 was cultured by plaque assay from the blood, brain, spinal cord, and liver of infected mice durin ... | 1984 | 6324031 |
| replication of coronavirus mhv-a59 in sac- cells: determination of the first site of budding of progeny virions. | during infection of sac- cells by murine coronavirus mhv a59 the intracellular sites at which progeny virions bud correlate with the distribution of the viral glycoprotein e1. budding is first detectable by electron microscopy at 6 to 7 hours post infection in small, smooth, perinuclear vesicles and tubules in a region transitional between the rough endoplasmic reticulum and the golgi apparatus. at later times the rough endoplasmic reticulum becomes the major site of budding and accumulation of ... | 1984 | 6325194 |
| sequence of murine coronavirus jhm induced neuropathological changes in rats. | infection of 21-25-day-old rats with the murine coronavirus jhm was followed either by an acute encephalomyelitis (ae) or subacute demyelinating encephalomyelitis (sde). the major neuropathological finding in ae, which developed within 6-12 days p.i. consisted of necrotizing lesions distributed mainly in the grey matter of the central nervous system (cns). sde developed 14-30 days p.i. and affected rats revealed lesions of primary demyelination with predilection sites in the white matter. the ti ... | 1984 | 6330603 |
| studies on the mechanism of rna synthesis of a murine coronavirus. | the mechanism of viral rna replication in mouse hepatitis virus (mhv)-infected cells was studied by oligonucleotide mapping of every mrna. we discovered that an oligonucleotide, no. 10, was localized at the 5'-end of every mrna, and was not colinear with the sequences of the virion genomic rna. this result indicates that all of the mrnas contain a leader sequence which is joined to the body sequences of the mrnas. we have also studied the structure of the replicative intermediate (ri) rna in the ... | 1984 | 6331110 |
| virological and immunological aspects of coronavirus induced subacute demyelinating encephalomyelitis in rats. | infection of rats with the murine coronavirus jhm led to acute or subacute encephalitis. viral and host factors greatly influenced the outcome of the infection. a number of temperature-sensitive (ts) mutants was obtained which differed widely in their capacity to induce lesions of the central nervous system (cns) in rats. under defined conditions a subacute demyelinating encephalomyelitis ( sde ) with pronounced clinical signs was observed 14-160 days post infection (p.i.). a number of rats, whi ... | 1984 | 6331117 |
| coronaviruses sd and sk share extensive nucleotide homology with murine coronavirus mhv-a59, more than that shared between human and murine coronaviruses. | a cdna probe representing the genome of mouse hepatitis virus (mhv) strain a59 (mhv-a59) was used to measure nucleotide sequence homologies among murine and human coronaviruses and the sd and sk coronaviruses isolated by burks et al. since sd and sk were isolated by inoculation of multiple sclerosis (ms) central nervous system (cns) tissue into mice or cultured mouse cells, it is important to determine their relationships to other murine and human coronavirus isolates. our results indicate that ... | 1983 | 6687965 |
| coronavirus jhm: tryptic peptide fingerprinting of virion proteins and intracellular polypeptides. | the virion proteins and intracellular polypeptides of the murine coronavirus mhv-jhm have been analysed by two-dimensional fingerprinting of their [35s]methionine-containing tryptic peptides. the analysis shows that the virion proteins gp98, gp65, pp60 and p23 are distinct. virion protein gp25 has the same polypeptide component as p23, and virion protein gp170 has a polypeptide component related to gp98. the six virus polypeptides synthesized in infected cells, 150k, 65k, 60k, 30k, 23k and 14k a ... | 1982 | 7142973 |