The RNA-binding protein PTBP1 is necessary for B cell selection in germinal centers

Nat Immunol. 2018 Mar;19(3):267-278. doi: 10.1038/s41590-017-0035-5. Epub 2018 Jan 22.


Antibody affinity maturation occurs in germinal centers (GCs), where B cells cycle between the light zone (LZ) and the dark zone. In the LZ, GC B cells bearing immunoglobulins with the highest affinity for antigen receive positive selection signals from helper T cells, which promotes their rapid proliferation. Here we found that the RNA-binding protein PTBP1 was needed for the progression of GC B cells through late S phase of the cell cycle and for affinity maturation. PTBP1 was required for proper expression of the c-MYC-dependent gene program induced in GC B cells receiving T cell help and directly regulated the alternative splicing and abundance of transcripts that are increased during positive selection to promote proliferation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibody Affinity / immunology
  • B-Lymphocytes / immunology*
  • Cell Differentiation / immunology
  • Cell Proliferation
  • Clonal Selection, Antigen-Mediated / immunology*
  • Germinal Center / immunology*
  • Heterogeneous-Nuclear Ribonucleoproteins / immunology*
  • Lymphocyte Activation / immunology*
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Polypyrimidine Tract-Binding Protein / immunology*


  • Heterogeneous-Nuclear Ribonucleoproteins
  • Ptbp1 protein, mouse
  • Polypyrimidine Tract-Binding Protein