Evaluation of cationic liposomes for delivery of diphtheria toxin A-chain gene to cells infected with bovine leukemia virus.
We investigated whether cationic liposomes are efficient at delivering the gene for diphtheria toxin A-chain (DT-A) under the control of the long terminal repeat (LTR) of bovine leukemia virus (BLV) (pLTR-DT) into BLV-infected cells and are also suitable for in vivo use. The transfection activity of the cationic liposomes composed of N-(alpha-trimethylammonioacetyl)-didodecyl-D-glutamate chloride (TMAG), dioleoyl phosphatidylethanolamine (DOPE) and dilauroyl phosphatidylcholine (DLPC) (1:2:2, molar ratio) (TMAG-liposome) and liposomes composed of phosphatidylserine (PS) (PS-liposome) was evaluated by the luciferase assay using a plasmid which contains the coding sequence of firefly luciferase under the control of the SR alpha promoter (pSR alpha/L-A delta 5). The TMAG-liposome gave highly efficient transfection in the presence of serum. On the other hand, PS-liposome showed inferior efficiency. When BLV-infected cells were co-transfected with a fixed amount of pSR alpha/L-A delta 5-entrapped TMAG-liposome and various amount of pLTR-DT-containing TMAG-liposome, the luciferase activity in the BLV-infected cells was inhibited by the addition of pLTR-DT-entrapped TMAG-liposome dose-dependently. The cationic TMAG-liposome containing pLTR-DT was successively added to BLV-infected cells in culture. The number of viable cells was markedly reduced by the cationic TMAG-liposome containing pLTR-DT. On the other hand, TMAG-liposome containing pSR alpha/L-A delta 5 showed no such effect. pLTR-DT entrapped by the cationic TMAG-liposome was not digested by the treatment with DNase I and with serum. These results suggest that the cationic liposomes, such as TMAG-liposome, may be efficient transfection reagent for the BLV-infected cells and can be utilized for DT-A gene delivery into the BLV-infected cells in vivo.
Lee
J T
JT
Department of Cell Chemistry, Okayama University Medical School, Japan.
Watarai
S
S
Kakidani
H
H
Onuma
M
M
Zhao
D D
DD
Yasuda
T
T
D000818:Animals; D002412:Cations; D002417:Cattle; D002461:Cell Line, Transformed; D003850:Deoxyribonuclease I / Q000494:pharmacology; D004167:Diphtheria Toxin / Q000008:administration & dosage* / Q000235:genetics*; D004337:Drug Carriers; D004587:Electrophoresis, Agar Gel; D016583:Enzootic Bovine Leukosis / Q000235:genetics / Q000628:therapy; D005814:Genes, Viral / Q000235:genetics; D015316:Genetic Therapy / Q000379:methods / Q000662:veterinary; D007668:Kidney / Q000196:embryology / Q000473:pathology / Q000821:virology*; D001909:Leukemia Virus, Bovine / Q000235:genetics / Q000302:isolation & purification*; D008081:Liposomes; D008156:Luciferases / Q000032:analysis; D010446:Peptide Fragments / Q000008:administration & dosage* / Q000235:genetics*; D010957:Plasmids; D012756:Sheep; D014162:Transfection / Q000379:methods*
D002412:Cations; D004167:Diphtheria Toxin; D004337:Drug Carriers; D008081:Liposomes; D010446:Peptide Fragments; C029795:diphtheria toxin fragment A; D008156:Luciferases; D003850:Deoxyribonuclease I