Allogeneic blood-based therapies: hype or hope?

The use of allogeneic blood therapies has opened new avenues in several medical fields including ophthalmology.1 Blood-based platelet and plasma products mimic natural tears because of their content in growth factors, cytokines, vitamins and nutrients, which are essential for maintaining the homeostasis of the normal ocular surface tissues.1 Although autologous eye drops are commonly used in the management of ocular disorders, not all patients are candidates as donors due to systemic inflammatory diseases, age, and other types of disorders or comorbidities. In these cases, an allogeneic blood-based product may represent an alternative to manage several ocular surface injuries, such as severe dry eye and persistent corneal epithelial defects.2, 3 The use of allogeneic therapies has major concerns, including hypersensitivity reactions in the recipient, the risk of blood-borne pathogen infection, and the requirement of tests for transfusion- transmissible infections and virus screening in the eye drops. Recently, solvent/detergent virally inactivated blood-based eye drops and the photochemical treatment of the allogeneic formulations have been proposed for virus inactivation.4