DNA vaccination strategies against infectious diseases

DNA immunisation represents a novel approach to vaccine and immunotherapeut ic development. Injection of plasmid DNA encoding a foreign gene of interes t can result in the subsequent expression of the foreign gene products and the induction of an immune response within a host. This is relevant to prop hylactic and therapeutic vaccination strategies when the foreign gene repre sents a protective epitope from a pathogen. The recent demonstration by a n umber of laboratories that these immune responses evoke protective immunity against some infectious diseases and cancers provides support for the use of this approach. In this article, we attempt to present an informative and unbiased representation of the field of DNA immunisation. The focus is on studies that impart information on the development of vaccination strategie s against a number of human and animal pathogens. Investigations that descr ibe the mechanism(s) of protective immunity induced by DNA immunisation hig hlight the advantages and disadvantages of this approach to developing vacc ines within a given system. A variety of systems in which DNA vaccination h as resulted in the induction of protective immunity, as well as the correla tes associated with these protective immune responses, will be described. P articular attention will focus on systems involving parasitic diseases. Fin ally, the potential of DNA immunisation is discussed as it relates to veter inary medicine and its role as a possible vaccine strategy against animal c occidioses. (C) 1999 Australian Society for Parasitology Inc. Published by Elsevier Science Ltd. All rights reserved.