Purpose: Posterior capsule opacification (PCO) is a vision-impairing disease that occurs in some adults and most children after cataract surgery. Contractile myofibroblasts contribute to PCO by producing wrinkles in the lens capsule that scatter light. Myofibroblasts in the lens originate from Myo/Nog cells named for their expression of the MyoD transcription factor and bone morphogenetic protein inhibitor noggin. In this study we tested the effects of depleting Myo/Nog cells on development of PCO.
Methods: Myo/Nog cells were eliminated by injecting the G8 antibody conjugated to 3DNA nanocarriers for the cytotoxin doxorubicin (G8:3DNA:Dox) during cataract surgery in rabbits. The severity of PCO was scored by slit lamp analysis, gross and histologic observation, and immunofluorescence localization of α-smooth muscle actin.
Results: G8:3DNA:Dox specifically induced cell death in Myo/Nog cells in the lens. None of the lenses administered G8:3DNA containing 9 to 36 μM doxorubicin developed greater than trace levels of central PCO and few myofibroblasts were present on the capsule. Less than 9% of these lenses exhibited greater than mild levels of peripheral PCO. Doxorubucin itself reduced PCO; however, myofibroblasts and wrinkles were abundant in the lens, and off-target effects were observed in the ciliary processes and cornea.
Conclusions: Myo/Nog cells are the primary source of myofibroblasts in the lens after cataract surgery. Targeted depletion of Myo/Nog cells has potential for preventing PCO and preserving vision.