A review of vaccine development and research for industry animals in Korea

Lee, Nak-Hyung; Lee, Jung-Ah; Park, Seung-Yong; Song, Chang-Seon; Choi, In-Soo; Lee, Joong-Bok

Naked DNA-based immunization has become a relatively novel approach in developing vaccines since the concept was reported in the 1990s. DNA vaccines have since been produced for a variety of diseases and tested in laboratories with considerable successes. They have successfully elicited efficient immunity to the antigen encoded by introduced genetic materials, which offer the potential for further advancement in the production of effective vaccine [34] . of intact antigen, the problem associated with the reversion of virulence can be minimized. In addition, DNA vaccines induce strong immunity conferring long lasting immunity associated with memory cells against a variety of bacteria and parasites [35] . The marked progress in recombinant DNA techniques over the past decades made it possible to generate a variety of DNA vaccines for various types of infectious agents. In recent years, DNA vaccine has become one of the most promising strategies for developing safe and efficient alternative vaccines, in particular for targeting highly virulent viral diseases. An advanced procedure for enhancing the immune response produced by DNA vaccines has recently been achieved by targeting desired antigens to specific antigen presenting cells (APC). Alternatively, many attenuated bacteria are specifically targeted to APCs responsible for immune reactions at designated locations, suggesting that they can be used to specifically deliver DNA to specific loci [35] . Such bacterial vectors include attenuated strains of Shigella, Listeria, and Salmonella in which the expression of the recombinant antigens are under the control of a eukaryotic promoter [36] . Unlike the recombinant protein vaccine alone, the recombinant vector vaccines have resulted in highly immunogenic response to foreign proteins. A vaccine retain the advantages associated with using live vectors, such as immunogenicity and ensuring delivery of the antigen in its native conformation, without many of the safety concerns associated with live-attenuated vectors [37] . Immunization with DNA vaccine is a vaccination approach that is being widely investigated to protect against a large number of infectious diseases.