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Updated: Jul 30, 2026

Analyzing the Functions of Mast Cells In Vivo Using 'Mast Cell Knock-in' Mice
09:07

Analyzing the Functions of Mast Cells In Vivo Using 'Mast Cell Knock-in' Mice

Published on: May 27, 2015

Functions of Bruton's tyrosine kinase in mast and B cells

Y Kawakami1, J Kitaura, D Hata

  • 1Division of Allergy, La Jolla Institute for Allergy and Immunology, San Diego, California 92121, USA.

Journal of Leukocyte Biology
|March 18, 1999
PubMed

Bruton's tyrosine kinase (Btk) plays crucial roles in B cell differentiation as well as mast cell activation through the high-affinity IgE receptor (FcepsilonRI). Defects in the btk gene lead to agammaglobulinemia (XLA) in humans and X-linked immunodeficiency (xid) in mice. Mast cells from xid and btk null mice exhibit mild defects in degranulation and severe impairments in the production of proinflammatory cytokines upon FcepsilonRI cross-linking. Recent studies demonstrated the role of Btk in a sustained increase in intracellular calcium concentrations in response to antigen receptor stimulation. Btk is also involved in the activation of stress-activated protein kinases, JNK/SAPK1/2, and thereby regulates c-Jun and other transcription factors that are important in cytokine gene activation. Regulation of the JNK/SAPK activation pathway by Btk may be related to the proapoptotic function of Btk in the programmed cell death in these hematopoietic cells.

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