Protective Immune Response to 16 kDa Immunoreactive Recombinant Protein Encoding the C‐Terminal VP1 Portion of Foot and Mouth Disease Virus Type Asia 1

Abstract

Recombinant protein of Foot and Mouth Disease Virus (FMDV) type Asia 1 corresponding to the C‐terminal half of VP1 was expressed in Escherichia coli. As an alternative to the synthetic peptide, this selected C‐terminal region was used as a protein vaccine in guinea pigs in order to study the immune response with various adjuvant formulations: immune stimulatory complexes (ISCOMs), Montanide ISA 206, Freund's incomplete adjuvant (FIA), lipopolysaccharide (LPS) and cytokine mixture. A primary dose of 40 μg/animal followed by a booster of the same dose was injected after a 21‐day interval. The sera were collected at intervals of 21, 42 and 63 days after the booster. The humoral response to vaccine was monitored by sandwich enzyme‐linked immunosorbent assay (ELISA) and a serum neutralization test (SNT). The guinea pig sera showed high titers both in ELISA and SNT, which could be protective. Further, irrespective of the adjuvant preparation used, the vaccine conferred protection against the challenge virus 105 days post‐vaccination in 13 of 15 animals (86%). The results indicated that a combination of recombinant protein ISCOMs and Montanide ISA 206 would be a better choice for achieving early protective titers and longer lasting immunity and that the C‐terminal half of the VP1 protein may be tried as a safe vaccine for secondary immunization.

Immunization with Outer Membrane Proteins of Pasteurella multocida (6:B) Provides Protection in Mice

“…Vaccines adjuvanted with Montanide oils have been reported to retain potency for a longer period than conventional aqueous formulations and elicit early, heightened and protective antibody titres and long lasting immunity (Bayry et al., 1999). When administered intramuscularly, no evidence of toxicity, prolonged pyrexia or local reactions at the site of inoculations is reported (Barnett et al., 1996).…”

Vaccine Potentiation by Combination Adjuvants

“…Noteworthy, antigen and ISCOM alone or CpG ODN alone were not efficient to induce anti-tumoral immune response and protection in mice. Another example to improve ISCOMS includes tubular immunomodulatory complexes [ 31 , 32 ] or the association with another adjuvant such as Montanide [ 33 ]. For example, when used in combination with a recombinant protein of food and mouth disease virus (FMD) in guinea pigs, higher immune responses were found when ISCOMs and Montanide ISA 206 were used in combination.…”

“…An example of a Montanide-based adjuvant is the Incomplete Seppic Adjuvant (ISA™, SEPPIC Inc. Fairfield, NJ, USA), which acts as oil-emulsion adjuvant, and which has been tested in combination with a number of experimental vaccines including a malaria vaccine [ 42 , 43 ]. Also, Montanides and ISCOMs were tested with a recombinant protein vaccine for FMD virus using guinea pigs [ 33 ]. Interestingly, this combination showed the greatest promise in inducing early and long-term protection.…”

VP1 of Foot-and-Mouth Disease Virus Induces Apoptosis via the Akt Signaling Pathway

“…Full-length and truncated forms of recombinant DNAderived VP1 (rVP1) of FMDV have been generated previously by several investigators (30). To solve the problem of poor water solubility, however, rVP1 has been routinely used together with denaturing agents such as urea (31).…”