Solvent/Detergent Virally Inactivated Serum Eye Drops Restore Healthy Ocular Epithelium in a Rabbit Model of Dry-Eye Syndrome

Abstract

Application of autologous serum eye drops (SEDs) is a recognized means to treat severe dry-eye syndrome (DES). Due to the inconvenience and difficulty of preparing SEDs from some patients, producing SEDs from allogeneic blood donations is gaining popularity. A major safety concern associated with allogeneic blood is virus transmission. We therefore herein evaluated the possibility of applying a solvent/detergent (S/D) treatment to inactivate viruses and studied the impacts of such treatment of SEDs to resolve DES in a rabbit model. Sera prepared from the blood of five rabbits were pooled and divided into two sub-pools. One was untreated (SEDs), while the other was virally-inactivated with 1% Tri-n-butyl phosphate/1% Triton X-45 at 31°C for 1 h (S/D-SEDs). DES was induced in rabbits using 0.1% benzalkonium chloride (BAC). Rabbits were divided into five groups of two rabbits each. One group was untreated (control), three were treated twice daily for 3 weeks using PBS, SEDs, or S/D-SEDs, and the last received an additional 0.1% BAC (as the negative control). The DES condition was determined by measuring aqueous tear secretion (Schirmer’s test), corneal fluorescein staining, a corneal histologic examination, TUNEL stain apoptosis, and corneal inflammatory marker (tumor necrosis factor-α, interleukin (IL)-1β, IL-8, and IL-6) expressions. We first confirmed that SEDs and S/D-SEDs had similar protein profiles and transforming growth factor (TGF)-β contents. Animal experiments showed that tear secretion did not significantly differ between the SED and S/D-SED groups but was significantly higher than in the PBS group. Eye fluorescein staining revealed dramatic improvements in epithelial defects in groups treated with SEDs or S/D-SEDs, and hematoxylin/eosin staining revealed microscopic epithelial layers similar to those of the untreated controls. Inflammatory markers and TUNEL studies showed that healthy epithelium had been restored in groups treated with SEDs or S/D-SEDs. In conclusion, this preclinical study supports the possibility of using S/D virally inactivated SEDs to treat DES and restore a normal epithelium.

Gelatin–epigallocatechin gallate nanoparticles with hyaluronic acid decoration as eye drops can treat rabbit dry-eye syndrome effectively via inflammatory relief

“…Tear secretion was quantified using Schirmer strips. 30,31 Rabbits were anesthetized to keep them immobile. After dispensing 0.5% Alcaine agent on the eye, the lower eyelid was pulled down slightly and Schirmer strips put on the palpebral conjunctival vesica, which is close to the connection of the middle and outer third of the lower eyelid.…”

Reflections on Dry Eye Syndrome Treatment: Therapeutic Role of Blood Products

“…As therapeutic platelet concentrates can be pathogen-inactivated using licensed treatment, this may speed-up the development of allogeneic pathogen-inactivated SED for clinical use ( 67 ). The well-established solvent-detergent (S/D) treatment, already applied to a wide range of biopharmaceutical preparations and plasma products ( 76 ), was experimentally proven applicable to rabbit SED ( 83 ). This S/D-treated rabbit serum was used as allogeneic SED equivalent to treat DES-rabbits, showing promising results.…”

Herbal Supplement in a Buffer for Dry Eye Syndrome Treatment

“…On the other hand, DES eyes treated with BS + FA100/KM1 did not demonstrate dye uptake ( Figure 6 d), suggesting that the damaged corneal epithelium had recovered. DES induced by BAC is a leading cause in pathological changes to the cornea, including squamous metaplasia and apoptosis, which are highly associated with inflammation [ 10 , 28 , 50 , 54 ]. Many studies indicate that BAC plays a significant role in the overexpression of IL1-β, IL-6, IL-8, and TNFα in epithelial cells as well as corneal protein extraction [ 10 , 49 , 50 , 51 , 54 ], which can promote apoptosis of both goblet and epithelial cells [ 50 ].…”

“…Tear amounts were measured by using Schirmer’s strips [ 47 , 54 ]. Rabbits were anesthetized firstly; then, following topical administration of 0.5% Alcaine ® eyedrops (20 µL), the lower eyelid was gently pulled down allowing for Schirmer’s strips to be placed on the palpebral conjunctival vesica.…”