Glycoprotein E-rns of pestiviruses induces apoptosis in lymphocytes of several species

Classical swine fever virus and bovine virus diarrhea virus are members of the genus pestivirus, which belongs to the family of the Flaviviridae, Recently, envelope glycoprotein E-rns was identified as an RNase, RNases can express different biological actions, They have been shown to be neurotoxic, antihelminthic, and immunosuppressive. We studied the immunosuppressive properties of E-rns in vitro, The glycoprotein totally inhibited concanavalin A induced proliferation of porcine, bovine, ovine, and human lymphocytes, We then studied the direct cytotoxic effects of E-rns on lymphocytes and epithelial cells in protein synthesis assays. E-rns strongly inhibited the protein synthesis of lymphocytes of different species, without cell membrane damage, This suggested an apoptotic process, and indeed apoptosis of lymphocytes was detected after incubation with E-rns, Pestivirus infections are characterized by leukopenia and immunosuppression, Our results suggest that E-rns plays an important role in the pathogenesis of pestiviruses.