PD-1 checkpoint blockade disrupts CD4 T cell regulated adaptive B cell tolerance to foreign antigengs

We utilized single cell-indexed custom RNA-sequencing to interogate the transcriptomes of IgG1 specific germinal center B cells and Plasma cells at steady state and six days after actue antibody mediated PD1 blockade B cells were isolated from the spleen of C57BL/6 mice at steady state (n=4) or six days after anti-PD1 blockade (n=4) . Phenotypically defined B cell subsets: naïve B cells (Gr1-FceR1a-IgD+IgMlowCD138-GL7-CD79b+CD19+CD38+), IgG1 Plasma Cells (Gr1-FceR1a-IgD-IgM-CD138+IgG1+), IgG1 Germinal Center B (Gr1-FceR1a-IgD-IgM-CD138- CD79b+CD19+CD38-GL7+IgG1+) were sorted into 384 well plates for library preparation. cDNA was amplied using a nested set of ~500 gene specific targeted primers. Transcriptional data was acquired from 1047 B cells across two experiments.