1 Cell and Tissue Biology and Cornea Departments, Instituto de Oftalmología Fundación de Asistencia Privada Conde de Valenciana, I.A.P, Mexico City, Mexico.
2 Department of Biochemistry, Faculty of Medicine, Universidad Nacional Autónoma de México, Mexico City, Mexico.
3 Department of Ophthalmology, School of Medicine, Duke University, Durham, NC, United States.