Repertoire-based approach to identifying sequence motifs specific to an effective vaccine

The T-cell repertoire response to the yellow fever vaccine builds near total immunity. To quantify the response of this high dimensional stochastic system we developed a statistical model of differential T-cell proliferation and used it as a basis for inference from high-throughput receptor sequencing data obtained from individuals pre and post vaccination. We used replicate data to infer parameters of the experimental variation of clone sizes, and pre and post vaccination data to quantify the response and identify candidate clones responsive to the vaccine by their posterior expansion probability. These candidates are experimentally validated and show above random sequence similarity.