Abstract
Mouse hepatitis viruses (MHV) are coronaviruses which cause various infections in mice affecting lung, intestine, liver, and other organs as well as the central nervous system. The replication of three different MHV strains was studied in mouse dissociated spinal cord cultures containing differentiated neurons and nonneuronal cells (NN) (including astrocytes). Cell tropism and maturation of each virus strain was analyzed by immunolabeling methods using antisera to the virion or to purified membrane glycoproteins (E1 and E2) and by electron microscopy (EM). Wt-JHM, which causes acute encephalitis in mice, produces acute cytopathic changes in both neurons and NN cells. In neurons, virions mature in smooth ER cisternae closely associated to the Golgi apparatus. As judged by EM, fewer virions are produced by neurons than NN cells and neurons do not fuse or stain for E2 as do NN cells. NN cells contain large inclusions made of nucleocapsid strands. A temperature-sensitive mutant of JHM, Ts8-JHM, which causes demyelination in mice, infects NN cells but not neurons. Infected NN cells synthesize E1 and E2, and contain large inclusions but few mature virions, even at permissive temperatures. These inclusions appear granular and rarely contain nucleocapsid strands in contrast to wt-JHM infection. NN cells infected with this mutant also display numerous membrane whorls. The hepatotropic strain A59 lacks tropism for neurons and primarily infects NN cells, thus resembling ts8-JHM. Infected NN cells become loaded with intracytoplasmic virions which are secreted from the cells. E1 can only be detected in the perinuclear area of these cells while E2 rapidly spreads throughout the cytoplasm. The cytoplasm of A59 infected NN cells frequently contains large tubular structures often in the lumen of the RER. In conclusion, in primary CNS cultures consisting of neurons and NN cells: (1) wt-JHM replicates in both neurons and NN cells but has different effects on these cells; (2) Ts8-JHM exhibits no productive infection of neurons, and in NN cells appears to be defective in assembly and to stimulate membrane synthesis; (3) A59 also shows tropism restricted to NN cells which produce many viruses and display differential distribution of the two virion glycoproteins. Thus, in the absence of the immune system, the MHV strains assayed exhibit differences in viral tropism, cytopathic changes, and viral assembly in CNS cells, and these differences may account for the different disease patterns.
Footnotes
The opinions expressed are the private views of the authors and should not be construed as official or necessarily reflecting the views of USU School of Medicine or the Department of Defense.
References
- Bignami A., Dahl D., Rueger D.C. Glial fibrillary acidic protein (GFAP) in normal neural cells and in pathological conditions. In: Fedoroff S., Hertz L., editors. Advances in Cellular Neurobiology. Academic Press; New York: 1980. pp. 285–310. [Google Scholar]
- David-Ferreira J.F., Manaker R.A. An electron microscope study of the development of mouse hepatitis virus in tissue culture cells. J. Cell Biol. 1965;24:57. doi: 10.1083/jcb.24.1.57. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dubois-Dalcq M., Hooghe-Peters E.L., Lazzarini R.A. Antibody-induced modulation of rhabdovirus infection of neurons in vitro. J. Neuropathol Exp. Neurol. 1980;39:507–522. doi: 10.1097/00005072-198009000-00001. [DOI] [PubMed] [Google Scholar]
- Faulkner G., Dubois-Dalcq M., Hooghe-Peters E., McFarland H.F., Lazzarini R.A. Defective interfering particles modulate VSV infection of dissociated neuron cultures. Cell. 1979;17:979–991. doi: 10.1016/0092-8674(79)90337-4. [DOI] [PubMed] [Google Scholar]
- Haspel M.V., Lampert P.W., Oldstone M.B.A. Vol. 75. 1978. Temperature-sensitive mutants of mouse hepatitis virus produce a high incidence of demyelination; pp. 4033–4036. (Proc. Nat Acad. Sci. USA). [DOI] [PMC free article] [PubMed] [Google Scholar]
- Herndon R.M., Griffin D.E., McCormick U., Weiner L.P. Mouse hepatitis virus-induced recurrent demyelination. Arch. Neurol. 1975;32:32–35. doi: 10.1001/archneur.1975.00490430054008. [DOI] [PubMed] [Google Scholar]
- Holmes K.V., Behnke J.N. Evolution of a coronavirus during persistent infection in vitro. In: terMeulen V., Siddell S., Wege H., editors. The Biochemistry and Biology of Coronaviruses. Plenum; London: 1982. in press. [Google Scholar]
- Holmes K.V., Doller E.W., Behnke J.N. Analysis of the functions of coronavirus glycoproteins by differential inhibition of synthesis with tunicamycin. In: terMeulen V., Siddell S., Wege H., editors. The Biochemistry and Biology of Coronaviruses. Plenum; London: 1982. in press. [Google Scholar]
- Holmes K.V., Doller E.W., Sturman L.S. Tunicamycin resistant glycosylation of a coronavirus glycoprotein: Demonstration of a novel type of viral glycoprotein. Virology. 1981;115:334–344. doi: 10.1016/0042-6822(81)90115-X. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hooghe-Peters E., Dubois-Dalcq M., Schmechel D. Visna virus induced fusion of nerve cells in vitro. Lab. Invest. 1979;41:247–255. [PubMed] [Google Scholar]
- Knobler R.L., Haspel M.V., Dubois-Dalcq M., Lampert P.W., Oldstone M.B.A. Host and virus factors associated with CNS cellular tropism leading to encephalomyelitis or demyelination induced by the JHM strain of mouse hepatitis virus. In: terMeulen V., Siddell S., Wege H., editors. Biochemistry and Biology of Coronaviruses. Plenum; New York: 1982. in press. [DOI] [PubMed] [Google Scholar]
- Knobler R.L., Dubois-Dalcq M., Haspel M.V., Claysmith A., Lampert P.W., Oldstone M.B.A. Selective localization of wild type and mutant mouse hepatitis virus (JHM strain) antigens in CNS tissue by fluorescence, light and electron microscopy. J. Neuroimmunol. 1981;1:81–92. doi: 10.1016/0165-5728(81)90010-2. [DOI] [PubMed] [Google Scholar]
- Knobler R.L., Haspel M.V., Oldstone M.B.A. Mouse hepatitis virus type 4 (JHM strain) induced fatal central nervous system disease. I. Genetic control and the murine neuron as the susceptible site of disease. J. Exp. Med. 1981;153:832–843. doi: 10.1084/jem.153.4.832. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lampert P.W., Sims J.K., Kniazeff A.J. Mechanism of demyelination in JHM virus encephalomyelitis. Electron microscopic studies. Acta Neuropathol (Berlin) 1973;24:76–85. doi: 10.1007/BF00691421. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lucas A., Flintoff W., Anderson R., Percy D., Coulter M., Dales S. In vivo and in vitro models of demyelinating disease: tropism of the JHM strain of murine hepatitis virus for cells of glial origin. Cell. 1977;12:533–560. doi: 10.1016/0092-8674(77)90131-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lucas A., Coulter M., Anderson R., Dales S., Flintoff W. In vivo and in vitro models of demyelinating diseases. II. Persistence and host-regulated thermo-sensitivity in cells of neural derivation infected with mouse hepatitis and measles viruses. Virology. 1978;88:325–337. doi: 10.1016/0042-6822(78)90289-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Powell H.C., Lampert P.W. Oligodendrocytes and their myelin-plasma membrane connections in JHM mouse hepatitis virus encephalomyelitis. Lab. Invest. 1975;33:440–445. [PubMed] [Google Scholar]
- Preble O.T., Costello L.E., Huang D.D., Barmada M.A. Neurovirulence mutant of vesicular stomatitis virus with an altered target cell tropism in vivo. Infect. Immun. 1980;29:744–757. doi: 10.1128/iai.29.2.744-757.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rentier B., Claysmith A., Bellini W.J., Dubois-Dalcq M. Chronic measles virus infection of mouse nerve cells in vitro. In: Bishop D.H.L., Compans R.W., editors. Replication of Negative Strand Viruses. Elsevier/North-Holland; New York: 1981. pp. 595–601. [Google Scholar]
- Rodriguez M., Dubois-Dalcq M. Intramembrane damages occurring during maturation of herpes simplex virus type I: Freeze-fracture study. J. Virol. 1978;26:435–447. doi: 10.1128/jvi.26.2.435-447.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stohlman S.A., Weiner L.P. Stability of neurotropic mouse hepatitis virus (JHM strain) during chronic infection of neuroblastoma cells. Arch. Virol. 1978;57:53–61. doi: 10.1007/BF01315637. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stohlman S.A., Weiner L.P. Chronic central nervous system demyelination in mice after JHM virus infection. Neurology. 1981;31:38–44. doi: 10.1212/wnl.31.1.38. [DOI] [PubMed] [Google Scholar]
- Sturman L.S., Takemoto K.K. Enhanced growth of a murine coronavirus in transformed mouse cells. Infect. Immun. 1972;6:501–507. doi: 10.1128/iai.6.4.501-507.1972. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sturman L.S., Holmes K.V. Characterization of a coronavirus. II. Glycoproteins of the viral envelope: Tryptic peptide analysis. Virology. 1977;77:650–660. doi: 10.1016/0042-6822(77)90489-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sturman L.S., Holmes K.V., Behnke J. Isolation of coronavirus envelope glycoproteins and interaction with the viral nucleocapsid. J. Virol. 1980;33:449–462. doi: 10.1128/jvi.33.1.449-462.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Weiner L.P. Pathogenesis of demyelination induced by a mouse hepatitis virus (JHM virus) Arch. Neurol. 1973;28:298–303. doi: 10.1001/archneur.1973.00490230034003. [DOI] [PubMed] [Google Scholar]