Abstract

SELF REPLICATING DNA VACCINE WITH POLYVALENT CTERMINAL IMMUNE REACTIVE PROTEIN GENE OF FOOT AND MOUTH DISEASE VIRUS, CONSTRUCTED FOR HUMORAL RESPONSE, ELICITS A HIGHER IMMUNE RESPONSE IN GUINEA PIGS AND PROTECTS AGAINST CHALLENGE VIRUSES.

Pranaya Pradhan, Reddy G. R., Suryanarayana V. V. S*, Sarika Sasi and Dechamma, HJ

Abstract

Foot and mouth disease of cloven footed animals is of great concern to the world because, of its devastating effect in the livestock industry. Regular mass vaccination with the conventional inactivated virus is a pragmatic approach to control FMD in endemic countries. However these vaccines have several drawbacks which include short duration of immune response, possible risk of virus dissemination during vaccine preparation and the vaccine is ineffective against carrier animals. In view of these several newer approaches are under investigation to develop alternative vaccines. One of this is the self replicating DNA/RNA vaccine using alpha virus replicase gene to augment the expression of the cloned immunogen and to elicit γ- interferon response. However the earlier work, based on this approach showed little success because of the lack of efficient presentation of the expressed antigen. Here we report the production of Self Replicating DNA/RNA vaccine that can elicit both humoral and cellular response in the vaccinated animals. Multiple epitope gene (990 bp) corresponding to the C-terminal major immunogenic region of VP1 of 3 serotypes (Indian vaccine strains), O, A, and Asia 1, linked in contiguous was cloned into the vector and the expression of the same was confirmed in BHK cell monolayers. The vaccine was evaluated in guinea pigs both for neutralizing anti-body response and protection against challenge with the three serotypes and found to be more efficacious. This approach, which is first of its kind may pave the way for development of potential vaccines against FMD.

Keywords: DNA vaccine, Foot and Mouth Disease (FMD), Sindbis virus Replicase, Immunization, self replication.