A Perina nuda cell line (NTU-Pn-HF) from pupal ovary that is persistently infected with a picorna-like virus (PnPV)

A new cell line, designated NTU-Pn-HF, was established from the pupal ovary of Perina nuda Fabricius (Lepidoptera: Lymantriidae) and characterized by distinct morphological properties and molecular markers. Pn-HF cells are highly susceptible to P. nuda nucleopolyhedrovirus (PenuNPV). Surprisingly, some of the sub-cultural Pn-HF cells suffered an obvious cytopathic effect (CPE) and proceeded to die, while most of the cells remained healthy with good nutrition. Under electron microscopy, most of the Pn-HF cells were found to be carriers of a picorna-like virus. A specific anti-P. nuda picorna-like virus (PnPV) antiserum and RT-PCR with a primer set designed from the sequence of a putative PnPV's helicase gene confirmed that the picorna-like virus in Pn-HF cells is PnPV (Wang et al., 1999, J. Invertebr. Pathol. 74: 62-68), and Pn-HF cells are persistently infected with PnPV. This finding implies that the Pn-HF cell line can be a PnPV supporter for further work, and also a convenient tool in studying the pathogenesis of insect picornavirus and the mechanism of the picornavirus-persistent infection.