The most recent development in vaccinology is immunization with polynucleotides. This technology has been referred to as genetic immunization or DNA immunization.

The basis for this approach to immunization is that, cells can take-up plasmid DNA and expresses the genes within the transected cells.

Thus, the animal acts as a bioreactor to produce the vaccine. This makes the vaccine relatively inexpensive to produce.

Some of the advantages of polynucleotide immunization are:


(1) It is extremely safe, induces a broad range of immune response (cellular and humoral responses)

(2) Causes long-lived immunity

(3) Can induce immune responses in the presence of maternal antibodies.

Most recently, it has also been used for immunizing fetuses. Thus, animals are born immune to the pathogens and at no time in the animal’s life are they susceptible to these infectious agents.


Although this is one of the most attractive developments in vaccinology, there is a great need to develop better delivery systems to improve the transfect ion efficiency in vivo.