Silencing of B cell receptor signals in human naive B cells

J Exp Med. 2002 Nov 18;196(10):1291-305. doi: 10.1084/jem.20020881.

Abstract

To identify changes in the regulation of B cell receptor (BCR) signals during the development of human B cells, we generated genome-wide gene expression profiles using the serial analysis of gene expression (SAGE) technique for CD34(+) hematopoietic stem cells (HSCs), pre-B cells, naive, germinal center (GC), and memory B cells. Comparing these SAGE profiles, genes encoding positive regulators of BCR signaling were expressed at consistently lower levels in naive B cells than in all other B cell subsets. Conversely, a large group of inhibitory signaling molecules, mostly belonging to the immunoglobulin superfamily (IgSF), were specifically or predominantly expressed in naive B cells. The quantitative differences observed by SAGE were corroborated by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) and flow cytometry. In a functional assay, we show that down-regulation of inhibitory IgSF receptors and increased responsiveness to BCR stimulation in memory as compared with naive B cells at least partly results from interleukin (IL)-4 receptor signaling. Conversely, activation or impairment of the inhibitory IgSF receptor LIRB1 affected BCR-dependent Ca(2+) mobilization only in naive but not memory B cells. Thus, LIRB1 and IL-4 may represent components of two nonoverlapping gene expression programs in naive and memory B cells, respectively: in naive B cells, a large group of inhibitory IgSF receptors can elevate the BCR signaling threshold to prevent these cells from premature activation and clonal expansion before GC-dependent affinity maturation. In memory B cells, facilitated responsiveness upon reencounter of the immunizing antigen may result from amplification of BCR signals at virtually all levels of signal transduction.

Publication types

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

MeSH terms

  • Antigens, CD34 / immunology
  • B-Lymphocytes / immunology*
  • Gene Expression Profiling
  • Humans
  • RNA, Messenger / genetics
  • Receptors, Antigen, B-Cell / immunology*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Signal Transduction / immunology

Substances

  • Antigens, CD34
  • RNA, Messenger
  • Receptors, Antigen, B-Cell