摘要
Objective Four B and Th cell epitopes were selected from conservative domain of Plasmodium falciparum antigens to construct two groups of chimeric malaria DNA vaccines with different configurations and their antigenicities were studied Methods The partially synthesized oligonucleotide was annealed, PCR amplified and cloned into a mammalian cell expression vector By using a pair of isocaudamers on the vector, different single copies of B epitopes were multiplied and were tenderly stringed into two groups of chimeric DNA vaccine with different configurations BALB/c mice were immunized with these DNA plasmids by either intramuscular or intradermal injections Results The antisera from the immunized mice tested by ELISA showed that only the configuration which had a single copy of universal T helper cell epitope, CS T3, located at the C terminal of the multi copy B cell epitopes induced a high antibody response The T helper cell epitope at any other position of the peptide, or the double T helper cell epitopes configured with the B cell epitopes did not enhance antibody response, and some configurations even decreased the humoral response to a B cell epitope Conclusion This study demonstrated that both combination and configuration of the epitope may affect the antigenicity of a chimeric multiple antigen
Objective Four B and Th cell epitopes were selected from conservative domain of Plasmodium falciparum antigens to construct two groups of chimeric malaria DNA vaccines with different configurations and their antigenicities were studied Methods The partially synthesized oligonucleotide was annealed, PCR amplified and cloned into a mammalian cell expression vector By using a pair of isocaudamers on the vector, different single copies of B epitopes were multiplied and were tenderly stringed into two groups of chimeric DNA vaccine with different configurations BALB/c mice were immunized with these DNA plasmids by either intramuscular or intradermal injections Results The antisera from the immunized mice tested by ELISA showed that only the configuration which had a single copy of universal T helper cell epitope, CS T3, located at the C terminal of the multi copy B cell epitopes induced a high antibody response The T helper cell epitope at any other position of the peptide, or the double T helper cell epitopes configured with the B cell epitopes did not enhance antibody response, and some configurations even decreased the humoral response to a B cell epitope Conclusion This study demonstrated that both combination and configuration of the epitope may affect the antigenicity of a chimeric multiple antigen
