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Characterization of G Protein-coupled Receptors by a Fluorescence-based Calcium Mobilization Assay
11:49

Characterization of G Protein-coupled Receptors by a Fluorescence-based Calcium Mobilization Assay

Published on: July 28, 2014

Impaired antigen receptor induced calcium mobilization in a phospholipase C-gamma1 deficient B cell line

Natarajan Muthusamy1, Do Joon Park, Hei-Won Rho

  • 1Center for Molecular and Human Genetics, The Department of Pediatrics, Columbus Children's Research Institute, The Ohio State University Columbus, OH 43205, USA. rmuthusa@chi.osu.edu

Immunology Letters
|December 23, 2003
PubMed

Insights

Phospholipase C-gamma(1) (PLC-gamma(1)) is crucial for B cell antigen receptor signaling. A B cell line lacking PLC-gamma(1) showed impaired calcium responses, highlighting its importance in B lymphocyte activation.

Area of Science:

  • Immunology
  • Cell Signaling
  • Molecular Biology

Background:

  • B lymphocytes utilize phospholipase C-gamma (PLC-gamma) isozymes for signaling.
  • The specific roles of PLC-gamma(1) and PLC-gamma(2) in B cell function remain unclear.

Purpose of the Study:

  • To investigate the role of PLC-gamma(1) in B cell signaling.
  • To analyze a B cell line specifically deficient in PLC-gamma(1).

Main Methods:

  • Characterization of PLC-gamma isozyme expression in various B cell stages and lines.
  • Analysis of B cell signaling responses, including calcium mobilization, upon antigen receptor stimulation.
  • Utilizing the L1.2 B cell line, which lacks PLC-gamma(1) but expresses PLC-gamma(2).

Main Results:

  • All tested B cells expressed PLC-gamma(1) and PLC-gamma(2), except the L1.2 cell line, which only expressed PLC-gamma(2).
  • L1.2 B cells exhibited normal surface IgM levels but failed to mobilize intracellular calcium upon antigen receptor stimulation.
  • PLC-gamma(1)-positive 70Z/3 cells showed a robust calcium response.

Conclusions:

  • PLC-gamma(1) is essential for antigen receptor-induced calcium signaling in B lymphocytes.
  • The L1.2 cell line provides a valuable model for studying PLC-gamma(1) and PLC-gamma(2) regulation in B cell calcium mobilization.

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