Improvement of a commercial foot-and-mouth disease vaccine by supplement of Quil A

In model animal experiment A, ICR mice were immunized with ovalbumin (OVA) adjuvanted with Quil A or mineral oil or their combination (Quil A+ oil). In model animal experiment B, ICR mice were immunized with foot-and-mouth disease virus (FMDV) antigens or with a commercially available oil adjuvanted foot-and-mouth disease (FMD) vaccine (type 0) alone or mixed with Quil A. After that, serum samples were collected to analyze specific IgG and IgG subclasses IgG L IgG2a, IgG2b, and IgG3. In experiment C, pigs were immunized with FMD (type 0) vaccine alone or together with Quil A. Serum samples were collected before and 4 weeks after immunization to analyze indirect haemagglutination (IHA) titers. Results from experiment A indicated a synergistic effect of Quil A and oil on IgG and the subclass responses. Experiment B revealed that supplement of Quil A in FMD vaccine significantly increased IgG and the subclass responses in mice. Experiment C demonstrated that supplement of Quil A in the FMD vaccine significantly enhanced humeral immune responses (as determined by IHA test) in pigs. It is concluded that supplement of Quil A in FMD vaccine can significantly enhanced immune responses and could be an alternative way to improve FMD vaccination in pigs. (c) 2007 Elsevier Ltd. All rights reserved.