BCR and influenza: To elucidate the effects of age on the B cell response to influenza vaccination, we carried out paired single-cell RNA-seq and BCR sequencing on enriched B cell samples prior to and 7 days following vaccination with standard-dose, seasonal inactivated influenza vaccine in young (age 20-30) and older (age 60-100) adults, all of whom showed at least a four-fold increase between pre- and post-vaccination HAI titer to at least one influenza strain in the vaccine.