Synthetic biology: impact on the design of innovative vaccines.

Conventional vaccine design strategies mainly focus on live-attenuated vaccines, inactivated microorganisms, and subunits thereof comprising purified components or recombinantly expressed proteins, mostly formulated with adjuvants. Although generally very efficient, these approaches are suboptimal or unfeasible for some infectious diseases. Over the past years new technologies to vaccine development have evolved, often utilizing design principles and construction technologies of synthetic biology. The contribution of synthetic biology to vaccine development comprises algorithms for accelerated in silico identification of relevant protein candidates, in silico design of novel immunogens with improved expression, safety and immunogenicity profiles as well as in silico design of (1) nucleic acid based, (2) vectored and (3) live-attenuated vaccines. Furthermore, synthetic biology enables economic and rapid chemical synthesis of DNA encoding the immunogens designed in silico, and their efficient assembly with delivery systems to obtain vectored vaccines. Altogether, synthetic biology can help to develop improved vaccine candidates in considerably less time compared to conventional approaches.