Preface [Hot topic: Current Molecular Approaches to Vaccine Design (Guest Editor: David C. Jackson)]

After clean water and good hygiene, vaccines are one of the most cost effective methods for improving public health. Vaccines can be used prophylactically and / or therapeutically in the treatment of infectious diseases as well as some cancers and also demonstrate potential in the treatment of autoimmune disorders. The requirements of regulatory authorities, however, demand that modern vaccines are rationally designed and thoroughly tested, indicating a move away from empirical approaches. This move has been accompanied by our increased understanding of the events, both molecular and cellular, that are necessary for immunity. As our knowledge of the mechanisms that underlie successful immune states increases, we are also learning how to induce immune responses that are appropriate for a particular disease state. In this issue of Current Drug Targets, articles are gathered together from six groups of researchers who are involved in the design of vaccines and other therapeutics against a diverse range of infectious diseases and cancers. Lin-fa Wang and Meng Yu open the issue with a review of the use of phage display libraries which can be used to identify those smallest of antigenic structures, epitopes, that are necessary for recognition by the effector molecules and cells of the immune system. The second review by Cameron Turtle and Derek Hart introduces the dendritic cell which in recent years has been increasingly recognised as being pivotal in determining the outcome of immune responses. The emphasis here is on the use of dendritic cells in cancer treatments but their importance in other vaccine applications is also made apparent. Joseph Torresi and his colleagues are next and review hepatitis C virus which has perhaps been unrecognised by the world at large as the causative agent of an epidemic which is second only to HIV. The strategies that viruses can adopt to avoid elimination by the immune system are made clear here, as well as some of the strategies that vaccinologists are using to counter this virus. Michael Batzloff, Sri Sriprakash and Michael Good follow our introduction to infectious diseases with an account of syndromes that are caused by streptococci and the vaccine strategies that are being brought to bear against this bacterium. The treatment of “strep throat” in developed countries where antibiotics are readily available may be thought to be trivial but the sequelae of streptococcal infections in developed and in less developed communities are serious indeed. HIV is of course known around the world but again no vaccine exists for its prevention or treatment. Ivan Stratov, Robert deRose, Damian Purcell and Stephen Kent are part of a large group that is deeply involved in finding a solution for HIV AIDS. As with Torresi's review of HCV, this account of the vaccine strategies which are being pursued against HIV make it clear that consideration of the pitfalls that can accompany inappropriate immune responses - in this case antibody that may enhance infection, must be made for vaccine strategies to be successful. The reviews so far, although using cutting edge technologies recently added to the arsenal of the vaccine designer, are all focused on inducing an active immune response. That is, the host responds with an immune response to inoculation with an antigen. The final review by Damon Eisen, Helen Liley and Robyn Minchinton describes the use of an alternative to conventional vaccines. This last article is appropriate because it describes a poorly appreciated protective system, that of innate immunity, and brings to our attention strategies which could be used to enhance the traditional armoury of active immunisation.