Marek's disease, a lymphoma caused by herpesvirus-replication dynamics, pathogenesis and vaccine effect

马立克氏病病毒（MDV）引起马立克氏病（MD），一种家禽淋巴瘤。MDV在全球普遍存在，因此几乎所有的商业鸡都接种了MD疫苗。未接种疫苗的鸡群中MD的发病率可高达20- 30%；在20世纪70年代早期引入MD疫苗之前，这种情况很普遍。MD疫苗的不同寻常之处在于，它不能预防强毒的MDV感染，而是疫苗病毒在与宿主中的强毒共存的同时阻止肿瘤的形成。这种现象发生的机制尚不清楚。MD肿瘤细胞含有MDV基因组，这意味着肿瘤细胞被病毒感染。由于MDV感染不会杀死MD肿瘤细胞，因此它们一定是潜伏感染的。否则，MDV会杀死被溶解感染的细胞。由于MDV在潜伏期仅产生少量病毒特异性蛋白和rna，因此检测这些潜伏感染的细胞非常困难。然而，为了了解MD的发病机制和疫苗接种机制，了解溶解性和潜伏性感染的动力学是至关重要的。

Marek's disease virus (MDV) causes Marek's disease (MD), a lymphoma of poultry. MDV is globally ubiquitous, thus almost all commercial chickens are vaccinated with the MD vaccine. Incidence of MD in unvaccinated chicken flocks can be as high as 20-30 %; this was commonly observed before the introduction of MD vaccines in the early 1970's. The MD vaccine is unusual in that it does not prevent virulent MDV infection, but rather the vaccine virus prevents tumor formation while co-existing with the virulent virus in the host. The mechanism by which this occurs is not well understood. MD tumor cells harbor the MDV genome, which means the tumor cells are infected with virus. Since MD tumor cells are not killed by the MDV infection, they must be infected latently. Otherwise MDV kills the lytically infected cells. It is very difficult to detect these latently infected cells as MDV makes only a few virus specific proteins and RNAs during latency. However, it is essential to know the dynamics of both lytic and latent infection in order to understand the pathogenesis and vaccination mechanisms in MD.