In vitro and in vivo Studies with an Avian Reovirus Derived from a Temperature-Sensitive Mutant Clone

Abstract

A temperature-sensitive (ts) mutant of avian reovirus isolate Maine 1-203 was obtained at 41 C. The 19th passage of this mutant (ts 19) was utilized for in vitro studies comparing its replication in macrophage cultures with that of its parent strain and an apathogenic S1133 virus. In vivo studies were initiated to determine the ts mutant's pathogenicity for day-old chicks, safety and protective levels for 6-day-old chicks, and interference with Marek's disease, Newcastle, and infectious bronchitis vaccinations. Although the results of in vitro trials indicated no difference among the three reoviruses in the in vitro pathogenicity for macrophage cultures, in vivo studies found the mutant to differ from its parent strain in pathogenicity for day-old chicks. When the ts mutant was administered at 6 days of age, it was a safe and effective vaccine against viral arthritis, with no resulting suppression of other vaccine responses.

Avian Reovirus Major μ-Class Outer Capsid Protein Influences Efficiency of Productive Macrophage Infection in a Virus Strain-Specific Manner

“…We have previously shown that the S1 genome segment, which encodes the p10 fusion protein of ARV, contributes approximately 60% of the embryo pathogenic potential of ARV-176 (8). In view of the ability of various strains of ARV to infect macrophages in vivo and under culture conditions (12,19,23,38), the transient immunosuppression that accompanies ARV-176 infection (25), and the central role of the macrophage in orchestrating the early immune response to virus infection, it is conceivable that the preferential infection of macrophages by ARV-176 in FIG. 6.…”

“…However, this would need to be directly evaluated in vivo, since the macrophage infection propensity of ARV-176 has never been evaluated in infected animals and the relationship between ARV macrophage infection and virus pathogenicity remains unclear (12,38). Similar confusion regarding the correlation between virus pathogenicity and macrophage infection exists with other viruses, such as herpes simplex virus (10,17).…”

“…Furthermore, there is evidence suggesting virus strain-specific differences in the ability of ARV to infect cultured macrophages (23). However, the relationship between macrophage infection and pathogenesis remains unclear (12,38). These studies prompted us to evaluate ARV-176 and ARV-138 macrophage interactions using an avian macrophage cell line, HD-11.…”

Interaction of avian reovirus with chicken lymphoblastoid cell lines

“…Avian reovirus has also been reported to replicate in chicken bone marrow-derived macrophages (Bülow & Klasen, 1983) and in blood monocyte cultures (Haffer, 1984) which might explain, in part, the reason for the observed immunosuppression. However, perusal of literature did not reveal any information about the interaction of avian reovirus with the different subsets of chicken lymphocytes.…”

Συμβολη Στη Μελετη Της Ανοσοπροφυλαξεως Των Ορνιθων Απο Την Ιογενη Αρθριτιδα

“…Οι ρεοϊοί των πτηνών πολλαπλασιάζονται επίσης σε κυτταροκαλλιέργειες από μακροφάγα κύτταρα του μυελού των οστών ή μακροφάγα που προέρχονται από μονοκύτταρα του αίματος (Bulow & Klasen, 1983" Haffer, 1984.…”