Expression of Bruton's tyrosine kinase protein within the B cell lineage

Eur J Immunol. 1994 Dec;24(12):3100-5. doi: 10.1002/eji.1830241228.


Defects in the gene encoding Bruton's tyrosine kinase (Btk), normally expressed in B cells, cause X-linked agammaglobulinemia (XLA). The phenotype of XLA is characterized by a lack of circulating B cells and immunoglobulin. It has been suggested that B cell maturation from the pre-B cell stage to more mature stages is dependent on the appropriate expression of this gene. The Btk mRNA is expressed in B cells and myeloid cells, but protein expression in relation to B cell maturation has not been determined. Moreover, expression of the Btk protein has so far only been investigated in human Epstein-Barr virus-transformed B cell lines, and in murine splenocytes and B cell lines. We have developed an antiserum which recognizes the human Btk protein and shown that normal human tonsillar B cells, peripheral blood monocytes and myeloid cells express the protein, whereas tonsil-derived T cells do not. We also show that the protein is present in early and mature human B cell lines, but is absent in terminally differentiated plasma cell lines. Furthermore, expression is reduced or absent in three B lineage cell lines derived from two patients with defined genetic mutations in Btk and suffering from XLA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Agammaglobulinaemia Tyrosine Kinase
  • B-Lymphocytes / cytology
  • B-Lymphocytes / enzymology*
  • Base Sequence
  • Blotting, Western
  • Cell Differentiation
  • DNA Primers / chemistry
  • Gene Expression Regulation, Developmental
  • Humans
  • In Vitro Techniques
  • Molecular Sequence Data
  • Plasma Cells / enzymology
  • Protein-Tyrosine Kinases / genetics
  • Protein-Tyrosine Kinases / metabolism*
  • RNA, Messenger / genetics


  • DNA Primers
  • RNA, Messenger
  • Protein-Tyrosine Kinases
  • Agammaglobulinaemia Tyrosine Kinase
  • BTK protein, human