Coadministration of DNA Encoding Interleukin-6 and Hemagglutinin Confers Protection from Influenza Virus Challenge in Mice

Diane L. Larsen; Naomi Dybdahl-Sissoko; Martha W. McGregor; Robert Drape; Veronica Neumann; William F. Swain; D. Paul Lunn; Christopher W. Olsen

Coadministration of DNA Encoding Interleukin-6 and Hemagglutinin Confers Protection from Influenza Virus Challenge in Mice

Department of Pathobiological Sciences¹ and
Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin—Madison, Madison, Wisconsin 53706,³ and
PowderJect Vaccines, Inc., Madison, Wisconsin 53711²

ABSTRACT

This study was conducted to investigate whether Accell gene gun coadministration of DNA encoding human interleukin-6 (IL-6) would enhance protective immune responses in mice to an equine influenza A virus hemagglutinin (HA) DNA vaccine. Mice that received HA DNA alone exhibited accelerated clearance of homologous challenge virus but were not protected from infection. In contrast, mice that received both HA and IL-6 DNA had no detectable virus in their lungs after challenge. These results strongly support the use of IL-6 as a cytokine adjuvant in DNA vaccination.

FOOTNOTES

Received 21 July 1997.
Accepted 21 October 1997.

↵* Corresponding author. Mailing address: Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin—Madison, 2015 Linden Dr. West, Madison, WI 53706. Phone: (608) 265-8681. Fax: (608) 263-0438. E-mail:olsenc{at}svm.vetmed.wisc.edu.