Nerve growth factor therapy for corneal disease

PURPOSE OF REVIEWTo review the experimental and clinical data on the effects of nerve growth factor (NGF) in corneal physiopathology and to discuss the future development of NGF therapy for corneal diseases. RECENT FINDINGSNGF plays a key role in the modulation of immune reaction, trophic support, healing of ocular surface, corneal sensitivity and tear film function. These properties of NGF make this neurotrophin a potential therapeutic agent for several corneal diseases. In this review, experimental evidence of the mechanisms of action of NGF on the ocular surface and clinical data on topical NGF use are described and discussed. This review includes the studies performed on corneal diseases such as neurotrophic keratitis, peripheral ulcerative keratopathy, dry eye and corneal surgery. Moreover, experimental studies that extended the NGF action on herpes virus corneal infection and ocular surface stem cell differentiation and proliferation are also reviewed. SUMMARYSince the first clinical use of topical NGF therapy in patients with neurotrophic keratitis, the ocular surface healing and immune-modulating actions of NGF have been extensively studied and demonstrated in the past two decades, opening new perspectives for its use in clinical practice in patients with infective and noninfective diseases of the ocular surface.