Multiple administration with interleukin-2 potentiates antigen-specific responses to subunit vaccination with bovine herpesvirus-1 glycoprotein IV.
Interleukin-2 has been described as an effective adjuvant for a number of antigens in different host species. Previously, we demonstrated the adjuvant activity of recombinant bovine IL-2 with a glycoprotein IV (gIV) subunit vaccine from bovine herpesvirus type-1 (BHV-1). In the present study, primary antibody responses were assessed in cattle immunized with either 2 or 50 micrograms of gIV, and treated with multiple doses of IL-2 or combinations of IL-2 and IFN-alpha or IL-2 and IFN-gamma. IL-2 was able to augment significantly antibody responses detected by either ELISA or virus neutralization. More significantly, IL-2 was able to enhance antibody titres in animals immunized with only 2 micrograms gIV to levels similar to those immunized with 50 micrograms gIV in the absence of IL-2. For optimal stimulation, multiple injections of IL-2 and Avridine had to be used in the formulation; other oil adjuvants or IL-2 alone could not induce a primary serum antibody response. Addition of IFN-alpha or IFN-gamma to the IL-2/gIV/Avridine formulation did not affect any of the immune parameters tested. As IFN-alpha is an effective immunoprophylactic agent for infectious bovine rhinotracheitis (IBR), combination vaccine-immunoprophylaxis may become feasible using IL-2 as a co-adjuvant. Thus, extremely low doses of antigen and only one immunization may be an effective vaccine given in combination with interferon prophylactic treatment.
Veterinary Infectious Disease Organization, Saskatoon, Saskatchewan, Canada.
H P
HP
Hughes
M
M
Campos
S
S
van Drunen Littel-van den Hurk
T
T
Zamb
L M
LM
Sordillo
D
D
Godson
L A
LA
Babiuk
D000818:Animals; D000956:Antigens, Viral / Q000276:immunology*; D002417:Cattle / Q000276:immunology*; D006023:Glycoproteins / Q000276:immunology*; D007242:Herpesvirus 1, Bovine / Q000276:immunology*; D007372:Interferons / Q000494:pharmacology; D007376:Interleukin-2 / Q000008:administration & dosage / Q000494:pharmacology*; D014611:Vaccination; D014764:Viral Proteins / Q000276:immunology*; D014765:Viral Vaccines / Q000008:administration & dosage / Q000276:immunology*
D000956:Antigens, Viral; D006023:Glycoproteins; D007376:Interleukin-2; D014764:Viral Proteins; D014765:Viral Vaccines; D007372:Interferons