Abstract:

Vaccinology is a field of bio-medical research involving the interaction of two distinct and complex entities: the structured, often variable and short-lived population of pathogens, and the diverse, structured and long-lived population of human hosts. To make the puzzle even more intricate, host-pathogen interaction is perturbed by vaccination in an intrinsically longitudinal manner: the pathogen is studied today, to vaccinate a subject tomorrow, to eventually protect him from infection. Over the last decade, quantitative methods ranging from quantitative genomics to biometry, to systems biology, have become the key to decipher the puzzle. We will consider a few practical examples: i) the concept of pan-genome, i.e. the finding that the genetic repertoire associated with a bacterial species can be potentially unbounded, and its impact on vaccine discovery, ii) the protein homology network as a tool to reduce the complexity of the whole bacterial pan-genome into coherent families of proteins evolved from a common ancestor, iii) predicting the rise of protective antibodies and persistence of immunologic memory in individual vaccines one year after the first immunization.