Foxo1 regulates marginal zone B-cell development

Eur J Immunol. 2010 Jul;40(7):1890-6. doi: 10.1002/eji.200939817.


A fundamental component of signaling initiated by the BCR and CD19 is the activation of phosphoinositide 3-kinase. Downstream of phosphoinositide 3-kinase, the protein kinase AKT phosphorylates several substrates, including members of the forkhead box subgroup O (Foxo) transcription factor family. Among the Foxo proteins, Foxo1 has unique functions in bone marrow B-cell development and peripheral B-cell function. Here, we report a previously unrecognized role for Foxo1 in controlling the ratio of mature B-cell subsets in the spleen. Conditional deletion of Foxo1 in B cells resulted in an increased percentage of marginal zone B cells and a decrease in follicular (FO) B cells. In addition, Foxo1 deficiency corrected the absence of marginal zone B cells that occurs in CD19-deficient mice. These findings show that Foxo1 regulates the balance of mature B-cell subsets and is required for the marginal zone B-cell deficiency phenotype of mice lacking CD19.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, CD19 / genetics
  • Antigens, CD19 / immunology
  • Antigens, CD19 / metabolism*
  • B-Lymphocytes / immunology
  • B-Lymphocytes / metabolism*
  • B-Lymphocytes / pathology
  • Cell Differentiation
  • Cell Proliferation
  • Cell Separation
  • Cells, Cultured
  • Flow Cytometry
  • Forkhead Box Protein O1
  • Forkhead Transcription Factors / genetics
  • Forkhead Transcription Factors / immunology
  • Forkhead Transcription Factors / metabolism*
  • Gene Expression Regulation, Developmental / immunology
  • Immunoglobulin Class Switching / genetics
  • Mice
  • Mice, Knockout
  • Precursor Cells, B-Lymphoid / immunology
  • Precursor Cells, B-Lymphoid / metabolism*
  • Precursor Cells, B-Lymphoid / pathology
  • Spleen / embryology
  • Spleen / immunology*
  • Spleen / pathology


  • Antigens, CD19
  • Forkhead Box Protein O1
  • Forkhead Transcription Factors
  • Foxo1 protein, mouse