Long-term functional assessment of encapsulated cells transfected with Tet-On system

Citation
Y. Hagihara et al., Long-term functional assessment of encapsulated cells transfected with Tet-On system, CELL TRANSP, 8(4), 1999, pp. 431-434
Citations number
10
Categorie Soggetti
Medical Research Diagnosis & Treatment
Journal title
CELL TRANSPLANTATION
ISSN journal
09636897 → ACNP
Volume
8
Issue
4
Year of publication
1999
Pages
431 - 434
Database
ISI
SICI code
0963-6897(199907/08)8:4<431:LFAOEC>2.0.ZU;2-J
Abstract
In our previous study, xenogeneic mouse neuroblastoma cells bearing the POM C gene, the precursor of ACTH and beta-endorphin, were implanted within pol ymer capsules into the CSF space of rats. Although ACTH and beta-endorphin were secreted, we were not able to control the amounts or times of hormone release. A promoter that is inducible by administration of tetracycline der ivatives (Tet) was linked to the POMC gene to control its gene expression ( Neuro2A-Tet-On-POMC; NTP). The results showed that POMC gene expression in the implanted encapsulated NTP cells could be regulated in a dose-dependent manner by Tet administration to the hosts. However, no analysis of gene co ntrol with the Tet-On system over a long period has been performed. In this study, encapsulated NTP cells were treated in vitro with doxycycline (Dox) (1.0, 10, 100, 1000 ng/ml) continuously for a month. On day 4, the amount of ACTH secretion was dependent on the Dox dose. But in the course of the e xperiment, the difference of ACTH secretion among those treated with Dox 10 , 100, and 1000 ng/ml was eliminated. On the other hand, NTP cells, which w ere treated with Dox (1000 ng/ml) just on days 7, 14, 21, and 28, secreted almost the same amount of ACTH in 24 h. From these results, for clinical us e, an NTP cell line that secretes enough opiate to reduce pain sensitivity without Dox should be established, and Dox could then be administered if ne cessary.