Purchase this article with an account.
Beatrice Yue, Sanja Turturro, Suhair Sunoqrot, Hongyu Ying, Seungpyo Hong; Microparticle Delivery of Matrix Metalloproteinase-3 to Trabecular Meshwork Cells. Invest. Ophthalmol. Vis. Sci. 2013;54(15):3540.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To test the feasibility of using microparticles for slow and sustained release of active matrix metalloproteinase-3 (MMP-3) to degrade extracellular matrix (ECM) elements such as fibronectin in cultured human trabecular meshwork (TM) cells. Accumulation of ECM materials in the TM is believed to be a contributing factor to intraocular pressure elevation, a major risk factor/cause of primary open angle glaucoma.
β-casein, with molecular weight (26 kDa) and hydrophobicity similar to those of the active MMP-3 fragment (19.2 kDa), was used for the initial testing. β-casein (2.2 mg) was encapsulated into poly(lactic-co-glycolic acid) (PLGA) microparticles following a double emulsion procedure. The protein amount encapsulated into the microparticles was measured by Bradford protein assay and the encapsulation efficiency was determined. The release test was conducted in Dulbecco’s Eagle’s minimum essential medium (DMEM) without or with the presence of human TM cells. Encapsulation of active MMP-3 (5 µg) into PLGA microparticles was subsequently carried out. Human TM cells pretreated with 100 nM of dexamethasone (DEX, to induce fibronectin expression) were set up as an assay platform for MMP-3. The fibronectin degradation or reduction of fibronectin levels was used as an indicator of the enzyme activity.
The encapsulation efficiency for β-casein was around 53%. The release test showed a slow and sustained release of β-casein over 20 days. The encapsulation efficiency for MMP-3 was estimated to be approximately 50%. The release medium collected from MMP-3-microparticle treated cultures, compared to that from empty- and β-casein-microparticle controls, markedly reduced the fibronectin staining in DEX-pretreated TM cells. The MMP-3 released to the culture medium was found active, still capable of degrading fibronectin after 9 days of incubation.
This study demonstrated the feasibility of encapsulating MMP-3 into polymeric microparticles and the potential of delivering active enzyme to TM cells.
This PDF is available to Subscribers Only