Infection by coronavirus JHM of rat neurons and oligodendrocyte-type-2 astrocyte lineage cells during distinct developmental stages

Abstract

Primary telencephalic cultures derived from neonatal Wistar Furth rats were able to support the growth of coronavirus JHM if a viable neuronal population was maintained. This occurred under serum-free defined, but not serum-supplemented, growth conditions. The importance of neurons in establishing infections in mixed cultures was confirmed by immunocytochemical and electron microscopic studies. Glia, although more abundant than neurons in these cultures, were less frequently infected during the initial 48 h postinoculation. The two glial lineages present in mixed telencephalic cultures were separated into type-i astrocytes and oligodendrocyte-type-2 astrocyte (0-2A) lineage cells and individually assessed for their ability to support virus growth. Infection could not be established in type-i astrocytes regardless of the culture conditions employed, consistent with our previous study (S. Beushausen and S. Dales, Virology 141:89-101, 1985). In contrast, infections could be initiated in selected 0-2A lineage cells grown in serum-free medium. Virus multiplication was however significantly reduced by preconditioning the medium with mixed telencephalic or enriched type-i astrocyte cultures, suggesting that intercellular interactions mediated by soluble factor(s) can influence the infectious process in 0-2A lineage cells. This presumption was supported by eliciting similar effects with basic fibroblast growth factor and platelet-derived growth factor, two central nervous system cytokines known to control 0-2A differentiation. The presence of these cytokines, which synergistically block 0-2A cells from differentiating into oligodendrocytes was correlated with specific and reversible resistance to JHM virus (JHMV) infection. These data, combined with our finding that accelerated terminal differentiation of the oligodendrocyte phenotype confers resistance to JHMV (Beushausen and Dales, Virology, 1985), suggest that the permissiveness of 0-2A cells for JHMV is restricted to a discrete developmental stage.

Coronavirus (JHM) Replication within the Retina: Analysis of Cell Tropism in Mouse Retinal Cell Cultures

“…Studies from a number of disciplines are showing that cell-to-cell interactions playa role in the survival, proliferation, and differentiation of cell populations. These influences have also been shown to be critical in the establishment of JHM virus infections in primary rat telencephalic cultures (Pasick and Dales, 1991). The studies reported here support earlier observations indicating that cell-to-cell interactions can influence retinal and RPE cell survival and proliferation (Campochiaro and Glaser, 1968).…”

“…This virus replication may also reflect a need for cell-to-cell interactions and/or a requirement for more differentiated cell types. Recent studies by Pasick and Dales (1991) indicate that two cell types, neurons and early oligodendrocyte type 2 astrocyte lineage cells, and specific stages of differentiation may be necessary for productive JHM virus replication. They discovered that the presence of soluble mediators which synergistically block 0-2A cells from differentiating into oligodendrocytes was correlated with specific and reversible resistance to JHM virus infections.…”

“…The acute infection is associated with viral replication in selected cells while chronic disease is associated with both virus replication and immune reactivity (Kyuwa and Stohlman, 1990). Many of the steps involved in pathogenic processes in these infections have been elucidated by in vitro studies (Lucas et al, 1977;Massa et et.. 1986;Pasick and Dales, 1991). Some of the studies have shown that virus pathogenesis has been associated with infection of specific cell types, such as glial cells, neurons, and oligodendrocytes.…”

“…Some of the studies have shown that virus pathogenesis has been associated with infection of specific cell types, such as glial cells, neurons, and oligodendrocytes. However, viral pathogenesis has also been associated with cell-to-cell interactions, release of cytokines, and state of differentiation of the cells (Pasick and Dales, 1991).…”

Sequence analysis of the spike protein gene of murine coronavirus variants: Study of genetic sites affecting neuropathogenicity

“…This differential entry may reflect the presence of different receptors utilized by wild-type virus versus selected variants. In addition, the susceptibility of different neural cells to JHM is known to be affected by the developmental stages of different cell species and host factors (Pasick and Dales, 1991). In the case of infection by JHM mutants, the immune response clears virus from the white matter by 12 days postinoculation but has the deleterious consequence of inducing myelin loss (Wang eT al., 1990).…”