3. Immune repertoire

 We are interested in immune repertoire, a collection of diverse immune cells in individuals, under situations where cancers and contagious diseases elicit our immune system. Previously, we analyzed the repertoire of serological antibodies upon influenza vaccination on the healthy and elderly people (DOI: 10.1172/JCI148763). B cell receptor (BCR) sequencing by NGS and proteomics enabled us to quantitatively understand dynamics of the repertoires. At the moment, we are investigating the BCR repertoires elicited by tumor cell injection in mice and tracing the clonal evolution in vivo system. Also, we work on identification of antigen-specific BCR sequences in vivo because in vivo immune systems function as effective screening systems to select functional clones from naturally-constructed enormous antibody repertoire. 

 As we are actively sequencing a variety of vaccines including mRNA and conventional vaccines by collaborating with vaccine companies, we plan to examine evolution of BCR repertoire upon types of vaccine and vaccine variants.