Checkpoints that control B cell development

J Clin Invest. 2015 Jun;125(6):2203-10. doi: 10.1172/JCI78083. Epub 2015 May 4.

Abstract

B cells differentiate from pluripotent hematopoietic stem cells (pHSCs) in a series of distinct stages. During early embryonic development, pHSCs migrate into the fetal liver, where they develop and mature to B cells in a transient wave, which preferentially populates epithelia and lung as well as gut-associated lymphoid tissues. This is followed by continuous B cell development throughout life in the bone marrow to immature B cells that migrate to secondary lymphoid tissues, where they mature. At early stages of development, before B cell maturation, the gene loci encoding the heavy and light chains of immunoglobulin that determine the B cell receptor composition undergo stepwise rearrangements of variable region-encoding gene segments. Throughout life, these gene rearrangements continuously generate B cell repertoires capable of recognizing a plethora of self-antigens and non-self-antigens. The microenvironment in which these B cell repertoires develop provide signaling molecules that play critical roles in promoting gene rearrangements, proliferation, survival, or apoptosis, and that help to distinguish self-reactive from non-self-reactive B cells at four distinct checkpoints. This refinement of the B cell repertoire directly contributes to immunity, and defects in the process contribute to autoimmune disease.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Autoimmune Diseases / immunology*
  • Autoimmune Diseases / pathology
  • B-Lymphocytes / immunology*
  • B-Lymphocytes / pathology
  • Cell Differentiation / immunology*
  • Cell Movement / immunology*
  • Gene Rearrangement, B-Lymphocyte / immunology*
  • Hematopoietic Stem Cells / immunology
  • Hematopoietic Stem Cells / pathology
  • Humans
  • Immunoglobulin Variable Region / immunology
  • Pluripotent Stem Cells / immunology
  • Pluripotent Stem Cells / pathology
  • Receptors, Antigen, B-Cell / immunology*

Substances

  • Immunoglobulin Variable Region
  • Receptors, Antigen, B-Cell