THE USE OF RECOMBINANT OVINE IL-1-BETA AND TNF-ALPHA AS NATURAL ADJUVANTS AND THEIR PHYSIOLOGICAL-EFFECTS IN-VIVO

In the present study we have investigated the use of recombinant ovine IL-1 beta and TNF-alpha both alone and in combination, as natural adj uvants in vaccination trials in sheep. Initial experiments were conduc ted to investigate the physiological effects of the cytokines in vivo and determine what dose could be administered without adverse pyrogeni c effects. Even at the maximum dose tested (100 mu g) the only signifi cant physiological effect was a transient increase in body temperature of approximately 2 degrees C in sheep injected with TNF-alpha. Admini stration of either cytokine had profound effects on the levels of circ ulating leucocytes for up to 5 days postinjection. The incorporation o f either IL-1 beta or TNF-alpha in aqueous or Al(OH)(3) vaccine formul ations enhanced antibody responses to a recombinant antigen from the c estode parasite Taenia ovis. The addition of IL-1 beta to aqueous vacc ine formulations increased antibody responses 15-20-fold and in Al(OH) 3 formulations by three to six fold. TNF-alpha stimulated 1.5 to six-f old and 2.5 to seven-fold increases in antibody levels in aqueous and Al(OH)(3)-based formulations, respectively, in a dose-dependent manner . The addition of either cytokine to Quil A or IFA vaccines did not en hance the antibody levels elicited. When 10 mu g of both IL-1 beta and TNF-alpha were incorporated in the aqueous or Al(OH)(3) vaccine formu lations, increases of 21-fold and 25-fold, respectively, were observed in antibody levels. The adjuvant activity of IL-1 beta and TNF-alpha in combination in the Al(OH)(3)-based vaccine resulted in antibody lev els commensurate with those obtained using Quil A or IFA.