A research team led by the University of New Hampshire developed a new hydrogel contact lens to effectively treat corneal melting, a severe eye disease that is the major cause for blindness worldwide.
Corneal melting, an uncontrolled degradation of corneal tissue, is an incurable eye disease that may lead to blindness. It is caused by infectious, inflammatory, trophic causes, chemical burns, or even as a side effect of eye surgery.
Corneal melting occurs when immune cells produce MMPs uncontrollably
This severe eye disease melts the cornea, and it occurs when an individual’s ocular immune cells start producing collagen degradation enzymes called matrix metalloproteinases (MMPs) uncontrollably. These enzymes are highly dependent on the presence of zinc ions, which they contain.
Current treatments of corneal melting include topical application of steroidal anti-inflammatory drugs, use of tissue adhesives, and transplantation of cornea. However, there is no cure for corneal melting to date.
Recently, a class of drugs called MMP inhibitors have been shown to treat this condition work by binding to the zinc ions within the MMPs. However, the presence of MMP inhibitors in the bloodstream can cause severe side effects by deactivating the zinc ions in other body tissues.
New hydrogel contact lens could deactivate MMPs
In a recent study supported by National Eye Institute and NIH Centers of Biomedical Research Excellence, a research team led by the University of New Hampshire developed a new hydrogel contact lens that can slow down the progression of corneal melting by deactivating MMPs.
By joining polar organic substances onto a hydrogel, the new hydrogel contact lens is capable of selective targeting and deactivating zinc ions. The researchers recently published their results in ACS Biomaterials Science & Engineering by The American Chemical Society.
In lab tests performed on extracted corneal tissue, the new hydrogel contact lens has been shown to effectively deactivate MMP-1, MMP-2, and MMP-9, which are the three major types of MMPs involved in corneal melting. Unlike conventional MMP inhibitors, the new hydrogel applies directly to the cornea via a contact lens to minimize the risk of serious nonspecific side effects.
This breakthrough innovation provides a new method to slow down the progression of corneal melting and other related ocular diseases. The research team has filed a pending patent, and more studies are required to determine the safety and efficiency of the products.
Written by Man-tik Choy, Ph.D.
Reference: Lopez, C et al. Matrix Metalloproteinase-Deactivating Contact Lens for Corneal Melting. ACS Biomaterials Science & Engineering, 2019;5:1195-1199. DOI: 10.1021/acsbiomaterials.8b01404.