Systems Biology in the Field of Vaccine Development

The conventional 3I (isolate, inactivate/attenuate, inject) strategy for vaccine development has contributed to the field of vaccinology much, and huge numbers of lives have been saved with the vaccines produced by this strategy. However, extensive knowledge on immunology and genetics was lacking during the development of such empirical vaccines. A more complete understanding of the biological processes underlying the infections such as human immunodeficiency virus needs novel systems to predict immune responses to novel vaccines in vivo. Systems biology is an approach to interrogate complex biological systems through investigation of numerous biomolecules by holistic approaches. The immune system involves more than 1500 genes/proteins in many interconnected pathways and processes, and a systems-level approach is vital in broadening our understanding of the immune response to vaccination. Critical genetic determinants of immune response found by systems biology can show the susceptibility to adverse events or reduced response to a vaccine. Systems biology also enables us to find out potent antigens to develop successful vaccines. Omics technologies including genomics, transcriptomics, and proteomics are the holistic tools that are used for systems biology. A recent field called systems vaccinology or vaccinomics has been proposed to describe the vaccine development using systems biology approaches. Thus, key elements for the protective immune responses and adverse events could be identified.