Asymmetric B Cell Division in the Germinal Center Reaction

Science  15 Dec 2011:

DOI: 10.1126/science.1213495


Lifelong antibody responses to vaccination require reorganization of lymphoid tissue and dynamic inter-cellular communication called the germinal center reaction. B lymphocytes undergo cellular polarization during antigen stimulation, acquisition, and presentation, which are critical steps for initiating humoral immunity. Here, we show that germinal center B lymphocytes asymmetrically segregate the transcriptional regulator Bcl6, the receptor for interleukin-21, and the ancestral polarity protein atypical PKC to one side of the plane of division, generating unequal inheritance of fate-altering molecules by daughter cells. Germinal center B lymphocytes from mice with a defect in leukocyte adhesion fail to divide asymmetrically. These results suggest that motile cells lacking constitutive attachment can receive provisional polarity cues from the micro-environment to generate daughter cell diversity and self-renewal.