Production of antibodies against Bacillus thuringiensis delta-endotoxin by injecting its plasmids

Bacillus thuringiensis insecticidal crystalline delta-endotoxin proteins are plasmid encoded. Specific antibodies against the delta-endotoxin were obtained in mice and rabbits by injecting isolated B. thuringiensis DNA plasmids into their muscles. Antibodies could be detected by ELISA as early as two weeks after the first injection. They formed immunoprecipitin lines with the toxin in the Ouchterlony agarose plate and neutralized the toxicity of the toxin. Because no special equipment, delivery mechanism or purification of the protein is required, this technique may provide a way to raise polyclonal antibodies to proteins encoded by bacterial plasmids and recombinant products.