Comparison of the ability of lactate dehydrogenase-elevating virus and its virion RNA to infect murine leukemia virus-infected or -uninfected cell lines

Abstract

Lactate dehydrogenase-elevating virus (LDV) has a strict species specificity. Cells or cell lines other than a particular subset of mouse primary macrophages which can support LDV replication in vitro have not been identified. LDV induces neurological disorders in old C58 or AKR strains, in which the involvement of multiple copies of the endogenous N-tropic murine leukemia virus (MuLV) genome and the Fv-1 locus of the mouse has been implicated. Our previous studies have demonstrated that LDV could infect and replicate in cell lines of the mouse or other species in vitro when they were infected with MuLV. The significance of and the precise mechanism underlying this phenomenon, however, remain unclear. We demonstrated in this study the efficient infection and replication of the virus in vitro by inoculation of its RNA mixed with liposome. No significant difference either in the efficiency of RNA transfection or in the ability to support its replication was observed among the various species' cell lines examined. In addition, by RNA transfection the virus replicated with equal efficiency in MuLV-infected and -uninfected cells or in macrophages derived from mice irrespective of their age. In contrast, the pattern of the infection by virus particles was quite different; LDV replication was observed only in macrophages (particularly from newborn mice) and MuLV-infected cells. By using various LDV isolates, it was demonstrated that the capability of replication between neurovirulent, LDV type C, and the other avirulent strains was almost the same in mouse cell lines when their RNA was introduced into the cells. Higher infectivity of LDV-C to MuLV-infected cells may be due to its efficient incorporation of the particles into MuLV-infected cells.

Analysis of protein expression by mammalian cell lines stably expressing lactate dehydrogenase-elevating virus ORF 5 and ORF 6 proteins

“…Immunofluorescence analysis revealed that the localization pattern of expressed ORF 5 and ORF 6 proteins was similar to that of LDV VP-3 and M/VP-2 in infected macrophages [20,21]. In addition, ORF 5 and ORF 6 proteins were colocalized in most cells.…”

“…Purified LDV type C (LDV-C) was prepared with 4 and 8-week-old SJL/J mice (Jackson Laboratory, Maine, USA) as described previously [20]. A polyclonal antibody (#36) against LDV M/VP-2 was obtained after immunizing rabbits with a synthetic polypeptide corresponding to the LDV-C ORF 6 C-terminal region coupled with the keyhole limpet hemocyanin (KLH) [21].…”

Two cellular proteins that interact with a stem loop in the simian hemorrhagic fever virus 3′(+)NCR RNA

“…This hypothesis further suggests that the cell proteins involved would be ones that are evolutionarily conserved among different mammalian species. In support of this hypothesis, it has been shown that the host range of individual arteriviruses is restricted at the level of virus attachment and that a single productive replication cycle occurs after transfection of viral genomic RNA into cells from a non-permissive host (Inada et al, 1993;Meulenberg et al, 1998;Kreutz, 1998). To determine whether other arterivirus 3 (+)NCR RNAs show cell protein binding patterns similar to that of the SHFV 3 (+)NCR RNA, UV-induced cross-linking assays were performed with these RNAs.…”

Production of virus-specific antiserum corresponding to sequences in the lactate dehydrogenase-elevating virus (LDV) ORF6 protein

“…Purified LDV type C (LDV-C) used in this study were prepared using 8-and 4-weekold SJL/J mice as described previously [9].…”

“…For Western blot analysis, virion protein extracted from LDV-infected SJL/J mouse sera were prepared as described previously [9,15]. The pelleted virus from infected sera was lysed in lysis buffer composed of 50 mM Tris -HCl (pH 8.0), 150 mM NaCl, 0.5% (wt/vol) sodium deoxycholate, 0.1% (wt/vol) sodium dodecyl sulfate (SDS), 1.0% Triton X-100 and Complete (Roche Diagnostics, Mannheim, Germany) as protease inhibitor cocktail.…”