Efficient Expansion of Human Granzyme B-Expressing B Cells with Potent Regulatory Properties.

Granzyme B-expressing B cells have been shown to be an important regulatory B cell subset in humans. However, it is unclear which subpopulations of B cells express GZMB under normal conditions and which protocols effectively induce ex vivo expansion of GZMB B cells. We found that in the peripheral blood of normal individuals, plasmablasts were the major B cell subpopulation that expressed GZMB.