Nanomedicine and Ocular Drug Delivery
The unifying theme of Dr. Xu’s research program is the synthesis and characterization of new biomaterials engineered to control the delivery of therapeutics for site-specific, controlled release of therapeutics to safely treat blindness and cancer, two critically important global health issues. The effect of nanoparticle (NP) physiochemical properties on NP behaviors ex vivo and in vivo will be explored, particularly with respect to the ability of NP to overcome biological barriers, like the transscleral diffusion barriers in the eye and stromal barriers in the solid tumor.
One major application of Dr. Xu’s nanomedicine research is for ocular drug delivery. Delivering therapeutics to the eye is a challenge on multiple levels since: (1) rapid clearance from the ocular surface of eye drops requires frequent instillation, which is difficult to comply for patients (glaucoma patients only take roughly one-half of their doses correctly), (2) transport of drugs and drug delivery vehicles across the blood-retinal barrier (BRB) when drugs are administered systemically, and through the cornea (topical drug administration) is difficult to achieve, (3) limited drug penetration to the back of eye due to various ocular barriers (cornea, conjunctiva, sclera and vitreous). The diseases that our lab is interested include corneal transplantation immunological rejection, diabetic retinopathy (DR), age-related macular degeneration (AMD), autoimmune uveitis. My ocular research program will focus on applying engineering principles to advance our understanding of disease pathophysiology and ocular barriers to drugs, while developing cutting-edge nanotherapeutic-based treatments for ocular disorders. My ocular research program can be translated to other promising but not fully studied pathways, like Wnt signaling (a master pathway regulating inflammation, angiogenesis and fibrosis in DR). The results and methodologies gained from my initial work on DR will be applicable to a wide spectrum of other ocular disorders and many systemic diseases, like cancer and autoimmune diseases.
The selected current active research projects in Dr. Xu’s lab:
Novel nanomedicine to prevent and treat corneal graft rejection (funded by a 5-year NIH R01 grant)
PPARα agonist drug delivery for treating diabetic retinopathy and age-related macular degeneration
Nanoparticle-based cancer therapy