Pigment epithelium-derived factor engineered to increase glycosaminoglycan affinity while maintaining bioactivity
Hunghao Chu1, Ivan T Rebustini2, S Patricia Becerra2
1Ionic Biomedical Inc., Ithaca, NY, 14850, USA.
Biochemical and Biophysical Research Communications
|March 25, 2022
Summary
Engineered pigment epithelium-derived factor (ePEDF) shows enhanced binding to the retinal extracellular matrix. This modification improves its therapeutic potential for retinal diseases by increasing retention and maintaining antiangiogenic and neuroprotective effects.
Area of Science:
- Ophthalmology
- Biochemistry
- Protein Engineering
Background:
- Pigment epithelium-derived factor (PEDF) is crucial for retinal homeostasis, offering antiangiogenic and neuroprotective benefits.
- Limited retention of PEDF in the retinal microenvironment hinders its therapeutic efficacy for eye diseases.
Purpose of the Study:
- To engineer PEDF to enhance its affinity for extracellular matrix (ECM) components, specifically heparin and hyaluronic acid (HA).
- To evaluate the therapeutic potential of engineered PEDF (ePEDF) for retinal diseases.
Main Methods:
- Amino acid modifications were introduced to convert neutral or anionic residues to cationic residues, creating ePEDF.
- In vitro binding assays were used to compare the affinity of ePEDF and wild-type PEDF (wtPEDF) for heparin and HA.
- In vitro and ex vivo models were employed to assess the antiangiogenic and retinal survival bioactivities of ePEDF.
Main Results:
- Engineered PEDF (ePEDF) demonstrated significantly higher binding affinity for heparin and hyaluronic acid (HA) compared to wild-type PEDF (wtPEDF).
- ePEDF exhibited potent antiangiogenic effects by inhibiting endothelial cell proliferation and tube formation in vitro.
- Ex vivo studies showed that ePEDF effectively protected photoreceptors from cell death in a model of retinal degeneration.
Conclusions:
- Protein engineering can enhance PEDF's affinity for the retinal ECM, improving its retention.
- ePEDF represents a promising therapeutic candidate for retinal diseases due to its enhanced binding and sustained bioactivity.
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