Combined Adjuvant Formulations Enhanced an Immune Response of Trivalent Foot and Mouth Disease Vaccine in Cattle

Abstract

Introduction: Foot-and-mouth disease is globally one of the most economically important viral diseases of cloven-hoofed animals that can be controlled by different strategies, where vaccination plays an important role. Selection of adjuvant added to vaccine preparation is crucial in ensuring the protective effect of the vaccine. Aluminum hydroxide gel mixed with saponin (AS) is widely used adjuvant, with its suboptimal immune response in FMD vaccine. The present study was undertaken to evaluate different ingredients of adjuvants for inactivated trivalent (A, O and SAT 2) FMD vaccine and to demonstrate the effect of booster dose in cattle.

Methods: Cattle were grouped into five; four experimental and one control, with six animals in each group and immunized with trivalent vaccine with various formulations of adjuvants. Immune response was measured using Solid Phase Competitive Enzyme Linked Immune Sorbent Assay (SPCE).

Results: The antibody level in cattle immunised with a vaccine formulation containing a mixture of aluminum hydroxide gel and saponin (AS) were significantly lower than AS boosted group for the three serotypes (p<0.05, t-test), which directs the need for booster dose. Whereas the antibody response in the AS + oil group was higher followed by oil alone. The AS preparation with a booster dose has shown better immune response compared to the group without.

Conclusion: The findings of this study could suggest that oil based and AS with oil could replace the conventional aluminum hydroxide gel and saponin adjuvants in FMD vaccine preparations. Challenge test was not successful indicating the need for further research on the virus infectivity.

Keywords: adjuvant; foot and mouth disease; immune response; serotype.

Figure 1

Line graphs displaying antibody response (OD value) of individual cattle in each experimental group using Solid Phase Competitive ELISA (SPCE) (serotype (A). Control (non-vaccinated animals), Oil (animals vaccinated with oil adjuvanted vaccine), AS (animals vaccinated with aluminum hydroxide gel and saponin adjuvanted vaccine), AS boost (animals vaccinated with aluminum hydroxide gel and saponin adjuvanted vaccine and boosted), AS + Oil (animals vaccinated with Aluminum hydroxide gel, saponin and oil adjuvanted vaccine). *Booster vaccination was given on 14th day.

Figure 2

Line graph showing the mean antibody response of all experimental groups against serotype A at 0, 7, 14, 21, 28 and 42 days post vaccination using Solid Phase Competitive Elisa (SPCE). The blue dotted line represents control groups; the red line represents groups vaccinated with aluminum hydroxide gel and saponin adjuvanted vaccine (AS); the green dotted line represents groups vaccinated with aluminum hydroxide gel and saponin adjuvanted vaccine and boosted (AS boosted); the red dotted line represents groups vaccinated with oil adjuvanted vaccine (Oil); and the black dotted line represents groups vaccinated with aluminum hydroxide gel, saponin and oil (AS + Oil). *Booster vaccination was given on 14th day.

Figure 3

Line graphs displaying the antibody response (OD value) of individual animals in each group using Solid Phase Competitive ELISA (SPCE) (serotype (O). Control (non-vaccinated animals), Oil (animals vaccinated with oil adjuvanted vaccine), AS (animals vaccinated with aluminum hydroxide gel and saponin adjuvanted vaccine), AS boost (animals vaccinated with aluminum hydroxide gel and saponin adjuvanted vaccine and boosted), AS + Oil (animals vaccinated with Aluminum hydroxide gel, saponin and oil adjuvanted vaccine). *Booster vaccination was given on 14th day.

Figure 4

Line graph showing the mean antibody response of the groups against serotype O at 0, 7, 14, 21, 28 and 42 days post vaccination using Solid Phase Competitive ELISA (SPCE). The blue dotted line represents control groups; the red line represents groups vaccinated with aluminum hydroxide gel and saponin adjuvanted vaccine (AS); the green dotted line represents groups vaccinated with aluminum hydroxide gel and saponin adjuvanted vaccine and boosted (AS boosted); the red dotted line represents groups vaccinated with oil adjuvanted vaccine (Oil); and the black dotted line represents groups vaccinated with aluminum hydroxide gel, saponin and oil (AS+ Oil). *Booster vaccination was given on 14th day.

Figure 5

Line graphs displaying the antibody response of individual animals in each group using Solid Phase Competitive ELISA (SPCE) (serotype SAT 2). Control (non-vaccinated animals), Oil (animals vaccinated with oil adjuvanted vaccine), AS (animals vaccinated with aluminum hydroxide gel and saponin adjuvanted vaccine), AS boost (animals vaccinated with aluminum hydroxide gel and saponin adjuvanted vaccine and boosted), AS + Oil (animals vaccinated with Aluminum hydroxide gel, saponin and oil adjuvanted vaccine). *Booster vaccination was given on 14th day.

Figure 6

Line graph showing the mean antibody response of the experimental groups against serotype SAT 2 at 0, 7, 14, 21, 28 and 42 days post vaccination using Solid Phase Competitive ELISA (SPCE). The blue dotted line represents control groups; the red line represents groups vaccinated with aluminum hydroxide gel and saponin adjuvanted vaccine (AS); the green dotted line represents groups vaccinated with aluminum hydroxide gel and saponin adjuvanted vaccine and boosted (AS boosted); the red dotted line represents groups vaccinated with oil adjuvanted vaccine (Oil); and the black dotted line represents groups vaccinated with aluminum hydroxide gel, saponin and oil (AS + Oil). *Booster vaccination was given on 14th day.