Cultured human trabecular meshwork cells express functional growth factor receptors

Area of Science:

• Ocular biology
• Cellular signaling
• Glaucoma research

Background:

• The human trabecular meshwork (HTM) is crucial for regulating intraocular pressure.
• Understanding growth factor receptor expression and function in HTM is vital for glaucoma research.

Purpose of the Study:

• To compare growth factor receptor mRNA expression in cultured HTM cells versus ex vivo HTM tissues.
• To determine if HTM cells exhibit physiological responses to exogenous growth factors.

Main Methods:

• Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect growth factor receptor mRNA in cultured HTM cells and ex vivo HTM tissues.
• Cell proliferation and extracellular acidification rate assays measured functional responses to growth factors.

Main Results:

• Fifteen growth factor receptor mRNAs were detected in both cultured and ex vivo HTM.
• Several growth factors (e.g., HGF, EGF, IGF-1, PDGF, FGF-2) stimulated HTM cell proliferation.
• Transforming growth factor-beta isoforms inhibited EGF-stimulated proliferation.
• Specific growth factors stimulated extracellular acidification, indicating functional receptor activity.

Conclusions:

• Cultured HTM cells and ex vivo HTM tissues express numerous growth factor receptors.
• These receptors are functional, mediating physiological responses in HTM cells.
• Growth factors may influence the HTM microenvironment and contribute to primary open-angle glaucoma pathogenesis.