title: Episomal lentiviral vectors confer erythropoietin expression in dividing cells.
abstract: Lentiviral vectors are now widely considered as one of the most common gene delivery tools for dividing and non-dividing cells. However, insertional mutagenesis has been found in clinical trials with retroviral vectors, which poses a safety risk. The use of non-integrating lentiviral (NIL) vectors, which avoid integration, eliminates the insertional mutagenesis problem. These NIL vectors are unable to mediate stable gene delivery into dividing cells, which makes them of limited use in the clinical practice of gene therapy. In this study, we constructed a NIL vector which harbors the scaffold/matrix attachment region (S/MAR) sequence and a therapeutic gene. NIL retained episomal erythropoietin (EPO) gene expression for 74days in dividing cells both with and without selection. Furthermore, Southern blot analysis showed that the NIL vector was retained extrachromosomally in CHO cells. In conclusion, the NIL vector based on an S/MAR sequence retained the extrachromosomal expression of a therapeutic gene in dividing cells. Our results show that NIL vectors maybe a safe and effective means of gene delivery, which is of potential clinical significance.
authors.affiliation: Department of Clinical Laboratory, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 10021, PR China. Electronic address: greatchenfeng@163.com.
authors.forename: Feng
authors.initials: F
authors.lastname: Chen
authors.affiliation: Department of Clinical Laboratory, China-Japan Union Hospital of Jilin University, Changchun 130031, Jilin, PR China.
authors.forename: Xin
authors.initials: X
authors.lastname: Qi
authors.affiliation: Department of Clinical Laboratory, Central Hospital of Qingdao, Qingdao 266042, Shandong, PR China.
authors.forename: Rong
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Department of Clinical Laboratory, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 10021, PR China.
authors.forename: Zong-Yong
authors.initials: ZY
authors.lastname: Wu
authors.affiliation: Department of Clinical Laboratory, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 10021, PR China.
authors.forename: Cui-E
authors.initials: CE
authors.lastname: Yan
authors.affiliation: Department of Clinical Laboratory, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 10021, PR China.
authors.forename: Jia
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Clinical Laboratory, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 10021, PR China.
authors.forename: Qiu-Ying
authors.initials: QY
authors.lastname: Liu
authors.affiliation: Department of Clinical Laboratory, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 10021, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Qi
mesh_terms: D000818:Animals; D016466:CHO Cells; D002455:Cell Division; D003412:Cricetulus; D004921:Erythropoietin / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D018014:Gene Transfer Techniques; D005822:Genetic Vectors / Q000737:chemistry / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D016086:Lentivirus / Q000235:genetics* / Q000378:metabolism; D020648:Peptide Elongation Factor 1 / Q000235:genetics / Q000378:metabolism; D010957:Plasmids / Q000737:chemistry / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D019076:Transgenes
chemical_list: C554270:EPO protein, human; D020648:Peptide Elongation Factor 1; D004921:Erythropoietin
keywords: EPO; Episomal vectors; Non-integrating lentivirus