PMID- 27684722
OWN - NLM
STAT- Publisher
LR  - 20191120
IS  - 1932-6203 (Electronic)
IS  - 1932-6203 (Linking)
VI  - 11
IP  - 9
DP  - 2016
TI  - FISH-Based Analysis of Clonally Derived CHO Cell Populations Reveals High 
      Probability for Transgene Integration in a Terminal Region of Chromosome 1 
      (1q13).
PG  - e0163893
LID - 10.1371/journal.pone.0163893 [doi]
LID - e0163893
AB  - A basic goal in the development of recombinant proteins is the generation of cell 
      lines that express the desired protein stably over many generations. Here, we 
      constructed engineered Chinese hamster ovary cell lines (CHO-S) with a pCHO-hVR1 
      vector that carried an extracellular domain of a VEGF receptor (VR) fusion gene. 
      Forty-five clones with high hVR1 expression were selected for karyotype analysis. 
      Using fluorescence in situ hybridization (FISH) and G-banding, we found that 
      pCHO-hVR1 was integrated into three chromosomes, including chromosomes 1, Z3 and 
      Z4. Four clones were selected to evaluate their productivity under non-fed, 
      non-optimized shake flask conditions. The results showed that clones 1 and 2 with 
      integration sites on chromosome 1 revealed high levels of hVR1 products (shake 
      flask of approximately 800 mg/L), whereas clones 3 and 4 with integration sites 
      on chromosomes Z3 or Z4 had lower levels of hVR1 products. Furthermore, clones 1 
      and 2 maintained their productivity stabilities over a continuous period of 80 
      generations, and clones 3 and 4 showed significant declines in their 
      productivities in the presence of selection pressure. Finally, pCHO-hVR1 
      localized to the same region at chromosome 1q13, the telomere region of normal 
      chromosome 1. In this study, these results demonstrate that the integration of 
      exogenous hVR1 gene on chromosome 1, band q13, may create a high 
      protein-producing CHO-S cell line, suggesting that chromosome 1q13 may contain a 
      useful target site for the high expression of exogenous protein. This study shows 
      that the integration into the target site of chromosome 1q13 may avoid the 
      problems of random integration that cause gene silencing or also overcome 
      position effects, facilitating exogenous gene expression in CHO-S cells.
FAU - Li, Shengwei
AU  - Li S
AD  - Key Laboratory of Bio-resources and Eco-environment (Ministry of Education), 
      College of Life Sciences, Sichuan University, Chengdu, Sichuan 610064, PR China.
AD  - Chengdu Bio-Tech Co. Ltd., Chengdu, Sichuan 610041, PR China.
FAU - Gao, Xiaoping
AU  - Gao X
AD  - Chengdu Bio-Tech Co. Ltd., Chengdu, Sichuan 610041, PR China.
FAU - Peng, Rui
AU  - Peng R
AD  - Key Laboratory of Bio-resources and Eco-environment (Ministry of Education), 
      College of Life Sciences, Sichuan University, Chengdu, Sichuan 610064, PR China.
FAU - Zhang, Sheng
AU  - Zhang S
AD  - Chengdu Bio-Tech Co. Ltd., Chengdu, Sichuan 610041, PR China.
AD  - Department of Physiology, West China School of Preclinical and Forensic Medicine, 
      Sichuan University, Chengdu, Sichuan 610064, PR China.
FAU - Fu, Wei
AU  - Fu W
AD  - Chengdu Bio-Tech Co. Ltd., Chengdu, Sichuan 610041, PR China.
AD  - Department of Physiology, West China School of Preclinical and Forensic Medicine, 
      Sichuan University, Chengdu, Sichuan 610064, PR China.
FAU - Zou, Fangdong
AU  - Zou F
AUID- ORCID: 0000-0002-2118-7076
AD  - Key Laboratory of Bio-resources and Eco-environment (Ministry of Education), 
      College of Life Sciences, Sichuan University, Chengdu, Sichuan 610064, PR China.
LA  - eng
PT  - Journal Article
DEP - 20160929
PL  - United States
TA  - PLoS One
JT  - PloS one
JID - 101285081
PMC - PMC5042417
COIS- Authors Shengwei Li, Xiaoping Gao, Sheng Zhang and Wei Fu received support in the 
      form of salary from Chengdu Bio-Tech Co. Ltd., a commercial company. There are no 
      patents, products in development or marketed products to declare. This does not 
      alter our adherence to all the PLOS ONE policies on sharing data and materials.
EDAT- 2016/09/30 06:00
MHDA- 2016/09/30 06:00
PMCR- 2016/09/29
CRDT- 2016/09/30 06:00
PHST- 2016/02/21 00:00 [received]
PHST- 2016/09/18 00:00 [accepted]
PHST- 2016/09/30 06:00 [entrez]
PHST- 2016/09/30 06:00 [pubmed]
PHST- 2016/09/30 06:00 [medline]
PHST- 2016/09/29 00:00 [pmc-release]
AID - PONE-D-16-07466 [pii]
AID - 10.1371/journal.pone.0163893 [doi]
PST - epublish
SO  - PLoS One. 2016 Sep 29;11(9):e0163893. doi: 10.1371/journal.pone.0163893. 
      eCollection 2016.