Antiviral effects of dual-target,antisense locked nucleic acid by cationic liposomes

Abstract

Objective To investigate the curative effects of dual-target antisense locked nucleic acid(LNA)targeting the S and C regions.Method Antisense LNA complementary to the S and C regions in the genome of HBV was synthesized respectively.Cationic liposomes was used as drug carrier which targeted antisense LNA to mice liver.LNA was incubated with cationic liposomes for 60 minutes to produce the targeted Lipo-LNA mixture.30 HBV transgenic mice were randomly divided into 5 equal groups:single-target S group,single-target C group,dual-target SC group,blank liposomes control group,and 5% GLU control group,to be injected into the caudal vein with corresponding Lipo-LNA mixture once for every other day.While in the control group,each mouse received the same volume(5% GLU)solution in the same way.Venous blood samples were collected before,and 1,3,5 days after the injection.Serum HBsAg was detected by time resolved fluoroisnmunoassy(TRFIA).HBV DNA was detected by real time PER,while serum Alb,ALT,BUN and Cr were measured by automatic biochemistry analyzer.5 days later,the mice were killed and immunohistochemistry was used to examine the HBsAg and HBcAg in the liver tissues.Pathological examination of the tissues was performed.Results The serum HBsAg concentrations in 1,3 and 5 days after injection were significantly lower than that before injection in the single-target S group,single-target C group and dual-target SC group(P<0.05).The inhibition rates in single-target S group were 23.3%,37.9% and 48.7% respectively,the rates in single-target C group were 21.2%,32.6% and 40.7%,and the rates in dual-target group were 30.6%,61.2%and 72.8%.In comparison with that before injection,the HBV DNA expression levels in 1,3 and 5 days after injection were significantly lower than in the single-target S group,single-target C group and dual-target SC group(all P<0.05).The inhibition rates in single-target S group were 12.6%,26.5%and 32.8%respectively,in single-target C group were 11.6%,24.5%and 27.3%,and in dual-target group were 18.5%,36.1%and 52.9%.HSsAg and HBcAg expressed in liver were significantly low in the single-target S group,single-target C group and dual-target SC group in 5 days later.No significant difference was found in the tissues in all groups.Conclusions Dual-target antisense LNA targeting the S and C regions in the genome of HBV inhibits the replication and expression of HBV significantly,and the inhibition is stronger than single-target antisense LNA. Key words: Cationic liposomes; Antisense locked nucleic acid; Hepatitis B virus; Mice,transgenic; Gene therapy