This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Wang, L. Articles by Bello, L. J. Search for Related Content PubMed PubMed Citation Articles by Wang, L. Articles by Bello, L. J.

Fusion to C3d Enhances the Immunogenicity of the E2 Glycoprotein of Type 2 Bovine Viral Diarrhea Virus

Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104

Received 15 July 2003/ Accepted 21 October 2003

The use of DNA and protein subunit vaccines in animals provides an opportunity to introduce vaccines that are arguably the safest that can be developed. For that reason, considerable effort is under way to devise methods of enhancing the immunogenicity of such vaccines. Seven years ago it was shown that fusing complement fragment C3d to hen egg lysozyme (HEL) enhanced the immunogenicity of HEL 10,000-fold. Based on this observation, we decided to evaluate the effect of C3d on the immunogenicity of the E2 protein of bovine viral diarrhea virus (BVDV). E2 is the major target of neutralizing antibody during BVDV infection. To test the effect of C3d on E2 immunogenicity, expression cassettes encoding a secreted form of E2 alone (E2s) or E2 fused to three copies of murine C3d (E2s-C3d) were constructed. The proteins were purified from the supernatants of transfected cells and used to immunize mice. The immune response was monitored by an enzyme-linked immunosorbent assay (ELISA) for E2s-specific antibody and by a virus neutralization test. The ELISA results indicated that the E2s-C3d protein is 10,000-fold more immunogenic than the E2s protein alone. The maximum primary immune response was elicited with <0.1 µg of E2s-C3d protein without an adjuvant. In addition, we have shown for the first time that high levels of anti-E2s and neutralizing antibodies can be elicited when this same low concentration of E2s-C3d is used to both prime and boost the immune response. We conclude that the E2s-C3d fusion protein has significant potential as a subunit vaccine against BVDV infection.

This article has been cited by other articles:

• Rosas, C. T., Konig, P., Beer, M., Dubovi, E. J., Tischer, B. K., Osterrieder, N. (2007). Evaluation of the vaccine potential of an equine herpesvirus type 1 vector expressing bovine viral diarrhea virus structural proteins. J. Gen. Virol. 88: 748-757 [Abstract] [Full Text]