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Updated: Jul 29, 2026

Genetic Modification and Recombination of Salivary Gland Organ Cultures
09:29

Genetic Modification and Recombination of Salivary Gland Organ Cultures

Published on: January 28, 2013

G-protein signaling abnormalities mediated by CD95 in salivary epithelial cells

X B Liu1, R Masago, L Kong

  • 1Department of Pediatrics, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, TX 78229-3900, USA.

Cell Death and Differentiation
|January 4, 2001
PubMed

Insights

Overexpressing Bcl-2 and Bcl-xL in salivary cells prevents apoptosis but leads to caspase activity and impaired function, potentially explaining Sjögren

Area of Science:

  • Cell Biology
  • Immunology
  • Oncology

Background:

  • Primary Sjögren's syndrome (SS) involves Fas-mediated apoptosis in salivary epithelial cells.
  • The roles of apoptosis-suppressing oncogenes Bcl-2 and Bcl-xL in salivary cells are poorly understood.
  • Understanding these oncogenes may offer strategies to prevent salivary gland destruction in SS.

Purpose of the Study:

  • To investigate the potential of Bcl-2 and Bcl-xL to prevent salivary gland destruction in SS.
  • To examine the effects of Bcl-2 and Bcl-xL overexpression on Fas-mediated apoptosis and cell function in salivary epithelial cells.

Main Methods:

  • HSY human salivary epithelial cells were stably transfected with Bcl-2 or Bcl-xL expression vectors.
  • Apoptosis was induced using anti-Fas antibody and quantified via flow cytometry.
  • Caspase activity, Ca2+ mobilization, and response to receptor agonists (carbachol, EGF) were measured.

Main Results:

  • Bcl-2 and Bcl-xL significantly inhibited Fas-mediated apoptosis in transfected cells.
  • Surprisingly, caspase activity remained despite apoptosis inhibition.
  • Fas activation in Bcl-2/Bcl-xL transfectants reduced cell responsiveness to agonists, an effect partially restored by caspase inhibition.

Conclusions:

  • Overexpression of Bcl-2 and Bcl-xL in salivary epithelial cells prevents Fas-mediated apoptosis but results in cells with active caspases.
  • These damaged cells exhibit impaired responsiveness to receptor agonists, potentially explaining severe dryness in SS patients.
  • This suggests a mechanism where inhibited apoptosis leads to dysfunctional cells, contributing to SS pathogenesis beyond cell death alone.

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