Metalloproteinases (MMPs) are modulators of inflammation and innate immunity involved in PDR and might be considered as a potential focus for the control of PDR [106]. Resveratrol, a polyphenol present in red wine, showed some activity in downregulating the levels of MMP-9 and protecting the retina from the ischemia [107].

An anti-angiogenic gene transfer of pigment epithelium-derived factor (PEDF) showed some benefits in the inhibition of NVE reducing the levels of MMP, VEGF, and connective tissue growth factor (CTGF) in an animal model of PDR [108].

Canakinumab is a novel monoclonal antibody against interleukin 1ß, which is currently used in rheumatic disorders. A pilot study evaluating the safety of 150 mg of canakinumab by subcutaneous injection in subjects affected by PDR is currently recruiting participants [109].

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Neelakshi Bhagat and Marco Attilo Zarbin

Contents

N. Bhagat, MD, MPH, FACS

Institute of Ophthalmology and Visual Science, New Jersey Medical School, Rutgers University, Room 6156, Doctors OfÞce Center Suite 6100,

90 Bergen Street, Newark, NJ 07103, USA

e-mail: bhagatne@rutgers.edu, bhagatne@umdnj.edu

M.A. Zarbin, MD, PhD (*)

Institute of Ophthalmology and Visual Science, New Jersey Medical School, Rutgers University, Room 6156, Doctors OfÞce Center Suite 6100,

90 Bergen Street, Newark, NJ 07103, USA

Department of Ophthalmology, University Hospital,

Room 6156, Doctors OfÞce Center, 90 Bergen Street, Newark, NJ 07103, USA e-mail: zarbin@rutgers.edu, zarbin@earthlink.net