The Gene Expression And Pathological Changes After Adenovirus-mediatedluciferase Gene Transfer To Rat Submandibular Glands

Gene therapy in salivary glands holds potential application for treatment of salivary gland diseases, oral diseases and systemic diseases. Gene transduction is the key that gene therapy will success or fail. This study that gene transfer to salivary glands is tall, new and sharp in field of gland's invesgation at present. It is expected to be applied to oral diseases and disorders and systemic diseases.. Untill now It is in the experiment stage of animal. There is no report gene transfer on salivary gland in Chinese literature. The purpose of this study is to investigate luciferase gene expression and pathological changes after adenvivus-mediated gene transfer to the submandibular glands of the rat.This study includes two parts:1. Adcmvluc gene transfer to rat's submandibular glands Fourty rats aged 8-10 weeks were included in this study. All rats were anesthetized with 3% mebumal. Atropine was delivered intramusclely 10min before gene transfer to inhibit saliva secretion in the glands. Forty rats were divided into five groups randomly, 8 rats in every group.Adcmvluc (108pfu) in 50ul was injected into bilaterial submandibular glands of 3 rats , and dexamethasone (1mg/180g) was given i.m. one time in every day for one week; three rats were only injected 50ul of 108pfu AdCMVluc ;two rats were injected diluted buffer. The submandibular glands of 5 groups were harvested in 3,7,14days,1, 2 months after gene transfer.The results include as following.Peak expression was observed three days following administation of the vector. Gene expression in the group of injection dexamethasone was higher than that in the group without injection of dexamethasone at 1 week. Gene expression in submandibular glands decreased with time gradually. Gene expression was still detected at 4 weeks and 8 weeks in this study, dexamethasone can increased gene expression in rat submandibular glands in 1 week.2. Pathological changes after gene transfer to submandibular glands of ratsThe pathological changes induced by retrograde injection of AdCMVLuc included : after 3 days Repression of acini ,dilation of terminal ducts, infiltration of lymphocytes and neutrophils in interlobular veins; after 1 week, more narrow cavity of acinus , lymphocytes and plasmacytes and oxyphil cells in blood vessel abside intralobular and interlobular duct; after two weeks , the necrosis material found in intralobular duct, more lymphocytes around interlobular and intralobular duct ; after 4 weeks, recovery evidence found in cavity of acinus, a little lymphocytes and monocytes around intralobular duct;after 8 weeks , normal acini and duct found .The ultrastructure changes included: after 3 days, increase of rough endoplasmic reticulum in acinus and ductal cell. Merge of mucus drops, decrease of microvillus in the cavity of gland, middle electron density matter in the cavity of glands. After 1 week, microvillus prolesses decreased in duct, mitochondrion increased significantly in acini cell. Intercellular space was enlarged.Conclusion:Adenovirus mediated gene transfer was successfully delived to rat's submandibular glands. Gene expression in submandibular glands decreased gradually with time. Dexamethasone can increased gene expression in rat submandibular glands in the early short period . Adenoviral mediated gene transfer to rat submandibular glands induced marked inflammatory reaction in the glands. The study presents the first report of ultrastructural changes after gene transfer to rat's submandibular glands. Increase of rough endoplasmic reticulum was found in the acini cells delivered with gene.