Abstract
Purpose:
Our group has been studying the feasibility of viral vector gene transfer to the lacrimal gland. The aims of this work are: a) to evaluated changes in the tear secretion and cells of ocular surface, b) to evaluate the changes in the lacrimal gland of rats with an adenovirus encoding the human erythropoietin (Epo) gene (AdLTR2EF1a-hEPO) or GFP (AdGFP).
Methods:
Male Wistar rats 6-8 weeks were divided into 3 groups (n = 5/group), where the control group received an injection of saline and the treated group received an injection of erythropoietin adenovirus (Ad-Epo) (20ul, 1012/ml ) and a group that received an injection of GFP adenovirus (Ad-GFP) (20 ul, 1012/ml) in the lacrimal gland. Data was collected 6 days after injection. The main parameters evaluated were tear secretion (phenol red thread), lacrimal gland (LG) and ocular globe histology, ocular surface impression citology (IC), expression of erythropoietin in the western blotting.
Results:
Tear secretion was not affected by viral vector gene transfer (control 5 ± 3.46mm, AdEpo 4± 1.73 mm and AdGFP 7± 1.29mm (p>0.05). IC revealed significant changes in cornea epithelia in AdEpo and AdGFP compared to controls (p=0.0079). At the6th day, there was no change in lacrimal gland or cornea histology compared to controls. The cornea epithelial thickness was 20.98± 3.16 µm in the control, 24.91± 1.08 µm in the AdEpo group and 24.72± 4.84 µm in the AdGFP group. Erythropoietin expression was significantly higher in transfected LG than controls (p<0.05).
Conclusions:
Adenovirus vector gene transfer was safe for lacrimal gland structure and function. Their impact on cornea epithelia needs further clarification. The present work offers additional information on the feasibility of gene therapy in the lacrimal gland. Support: FAPESP, CNPq, NAP-FTO USP, Capes.
Keywords: 576 lacrimal gland •
411 adenovirus •
561 injection