Effects of inactivated parapoxvirus ovis on cellular and humoral events of the innate immune response in mice

Non-replicating Newcastle Disease Virus as an adjuvant for DNA vaccine enhances antitumor efficacy through the induction of TRAIL and granzyme B expression

The potential of non-replicating Newcastle Disease Virus (NDV) as an adjuvant for DNA vaccination remains to be elucidated. To assess the therapeutic effects of DNA vaccine (HPV-16 E7 gene) adjuvanted with NDV, female C57/BL6 mice were inoculated with murine TC-1 cells of human papillomavirus (HPV)-related carcinoma, expressing human papillomavirus 16 (HPV-16) E6/E7 antigens, and immunized with DNA vaccine alone or pretreated with NDV. One week after third immunization, Cytotoxic T lymphocytes (CTLs), splenocyte proliferation, cytokine balance (IFN-γ, IL-4 and IL-12 secretions) and intratumoral expression of cytotoxicity related proteins in tumor lysates were investigated. The results showed that treatment with non-replicating NDV prior to DNA vaccine induced tumor-specific cytolytic and splenocyte proliferation responses. The levels of cytokines IL-12, IL-4 and IFN-γ after treating with combined E7-DNA -non-replicating NDV (NDV-DNA Vaccine) were significantly higher than those of control groups. The intratumoral granzyme B and Tumor Necrosis Factor Related Apoptosis Inducing Ligand (TRAIL)-mediated apoptosis was also significantly increased. Tumor therapeutic experiments showed that the NDV pretreatment could reduce the tumor progression of established E7-expressing TC-tumors. Taken together these data suggest that the significant antitumor responses evidenced during treatment with non-replicating NDV prior to DNA vaccine are due, in part, to strong E7-induced cellular immunity and enhanced expression of cytotoxicity related proteins in the tumor microenvironment. These observations indicated the potential of non-replicating NDV as an adjuvant for enhancing therapeutic DNA vaccines -induced immunity and antitumor responses.

Inactivated Parapoxvirus ovis as inducer of immunity in silver catfish (Rhamdia quelen)

Molecules with immune modulating activity are ubiquitously distributed in nature and their impact on aquaculture has been exploited in order to increase fish resistance to pathogens. Here, we investigated the effect of inactivated Parapoxvirus ovis (iPPVO) on blood cells and innate and acquired immune response of silver catfish (Rhamdia quelen). iPPVO inoculation had no effect on respiratory burst activity; however, following iPPVO inoculation, we observed a significant decrease on circulating monocytes concomitantly with an increased number of heterophilic granulocytes and thrombocytes, which are the main cells involved in innate immunity and provide connection with acquired immunity. Fish inoculated with a combination of bovine serum albumin (BSA) + iPPVO had significantly higher levels of antibodies to BSA compared to fish inoculated with BSA alone, but lower than fish inoculated with BSA + Freund's incomplete adjuvant (FIA). These findings points to the potential usefulness of iPPVO as immunomodulator in fish and instigate further research to identify its component that interact with immune cells and that could be exploited as adjuvants in fish.