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Primary Culture of Porcine Retinal Pigment Epithelial Cells
Published on: September 23, 2022
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TGF-β2 secretion from RPE decreases with polarization and becomes apically oriented
Louis Hirsch1, Hossein Nazari1, Parameswaran G Sreekumar2
1Department of Ophthalmology, Keck School of Medicine of the University of Southern California, United States.
Cytokine
|December 16, 2014
Summary
Polarity influences transforming growth factor beta 2 (TGF-β2) secretion by retinal pigmented epithelium (RPE). Loss of RPE polarity in proliferative vitreoretinopathy (PVR) may increase intravitreal TGF-β2 levels.
Area of Science:
- Ophthalmology
- Cell Biology
- Biochemistry
Background:
- Retinal pigmented epithelium (RPE) secretes transforming growth factor beta (TGF-β) cytokines.
- TGF-β isoforms are implicated in fibrosis, immune privilege, and proliferative vitreoretinopathy (PVR).
- RPE cell polarity is often altered in retinal diseases like PVR and age-related macular degeneration.
Purpose of the Study:
- To investigate the impact of RPE cell polarity on TGF-β secretion.
- To compare TGF-β levels between polarized and nonpolarized human RPE (hRPE) and human stem cell-derived RPE (hESC-RPE).
Main Methods:
- Cultured polarized and nonpolarized hRPE and hESC-RPE cells.
- Quantified TGF-β1 and TGF-β2 secretion under different polarity conditions.
- Assessed the localization and activity of secreted TGF-β2.
Main Results:
- TGF-β2 was the predominant TGF-β isoform secreted by RPE cells.
- Nonpolarized RPE cells secreted significantly higher levels of TGF-β2 compared to polarized cells.
- Active TGF-β2 was primarily secreted from the apical side of polarized RPE cells, constituting 6-10% of total TGF-β2.
Conclusions:
- RPE cell polarity is a critical determinant of TGF-β2 secretion.
- Reduced RPE polarity in PVR may contribute to elevated intravitreal TGF-β2.
- Polarized hESC-RPE exhibits comparable TGF-β secretion to hRPE, supporting its therapeutic potential for RPE replacement.
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