Transcriptomic analysis of human B cell responses to vaccination

Analysis of the gene expression profiles of naïve B cells, resting memory B cells (MBCs), activated B cells (ABCs) and antibody-secreting cells (ASCs) isolated from peripheral blood one week following influenza vaccination. Upon antigen exposure B cells eventually bifurcate into two distinct lineages, plasmablasts and memory B cells. We previously reported that plasmablasts or antibody-secreting cells (ASCs) could be transiently detected in blood shortly after infection or vaccination of humans. Here, we define the phenotype and the transcriptional program of a novel human antigen-specific B cell subset, referred to as activated B cells (ABCs). ABCs do not spontaneously secrete antibodies and possess a unique transcriptional profile that distinguishes them from ASCs and resting memory B cells. Clonal lineages present among day 7 ABCs persisted in blood for up to three months post-influenza immunization indicating that ABCs may be destined to join the long-term memory B cell pool. ABCs and ASCs can be clearly distinguished in blood following influenza and Ebola virus infections. Interrogating ABCs will expand our understanding of the differentiation, maturation and longevity of human B cell responses. Total RNA was isolated from 10,000 cells of each population.