13 Oncogenic Herpesviruses

Abstract

In Chapter 12 we discussed the molecular biology and genetics of the herpesviruses, particularly herpes simplex viruses 1 and 2. In this chapter we describe what is known about several oncogenic herpesviruses that transform cultivated cells (for review, see Sugden et al. 1979a); some of these viruses are, or are suspected of being, carcinogens in their natural host species (see Table 13.1). The survey begins with Marek’s disease virus (MDV). Although MDV does not currently attract much attention from tumor virologists, it is of special interest because it causes the only naturally occurring lymphoproliferative disease that can be effectively controlled by vaccination (for review, see Biggs 1975).

MAREK’S DISEASE AND MAREK’S DISEASE VIRUS
Marek’s disease afflicts chickens; its classical symptoms are a generalized lymphomatosis involving lymphocytic invasion of nerve trunks and subsequent paralysis of the bird (Marek 1907, Biggs 1968). An acute form of the disease is characterized by the rapid formation of polyclonal lymphomas and, in infected flocks, by a high mortality (Biggs et al. 1965). The causative agent of this acute form of the disease is MDV, a herpesvirus first isolated by cocultivating cells from infected birds with chick kidney cells or duck embryo fibroblasts (Churchill and Biggs 1967; Biggs et al. 1968). After attenuation by passage through chicken kidney cells, live MDV was used successfully as a vaccine against the disease (Churchill et al. 1969a,b).

The early development of effective vaccines minimized incentives to study the virus in great detail, and we know very little about the...