Transfection of adult canine Schwann cells and olfactory ensheathing cells at early and late passage with human TERT differentially affects growth factor responsiveness and in vitro growth.
Adult canine Schwann cells and olfactory ensheathing cells (OECs) are closely related cell types that are considered attractive candidates for translational studies of neural repair. To establish a reliable cell source by comparing the in vitro properties of immortalized Schwann cells and OECs for transplantation purposes, we transfected both cell types with human telomerase reverse transcriptase (hTERT). Ectopic hTERT expression has been shown to induce immortalization of various cell types without substantial alterations of their phenotypes. Schwann cells and OECs were isolated from adult dogs, transfected with hTERT at early (P4) and late passage (P26), characterized regarding in vitro proliferation, antigenic expression and senescence-associated genes in the presence and absence of fibroblast growth factor-2 (FGF-2). Ectopic hTERT expression in late passage glia treated with but not without FGF-2 prevented the decline in proliferation observed in non-transfected cells. Immortalization did not alter p75(NTR) and GFAP but O4 and A2B5 expression. Contrary to this, early passage hTERT transfection significantly reduced proliferation independent of FGF-2 and lowered expression of O4 and GFAP in both cell types. Transfection did not alter mRNA expression of senescence-associated genes such as p53 and p16. No substantial differences were found between Schwann cells and OECs underscoring the close relationship of both cell types. Taken together, we established a stable source of adult canine Schwann cells and OECs and demonstrated that the effects of hTERT expression on in vitro growth and growth factor responsiveness depend on the replicative age.
Techangamsuwan
Somporn
S
Department of Pathology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany.
Kreutzer
Robert
R
Kreutzer
Mihaela
M
Imbschweiler
Ilka
I
Rohn
Karl
K
Wewetzer
Konstantin
K
Baumgärtner
Wolfgang
W
D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects / Q000235:genetics; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D004285:Dogs; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology; D005732:Gangliosides / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects / Q000235:genetics; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D006801:Humans; D019081:O Antigens / Q000378:metabolism; D009831:Olfactory Mucosa / Q000166:cytology*; D020800:Receptor, Nerve Growth Factor / Q000378:metabolism; D012583:Schwann Cells / Q000166:cytology* / Q000187:drug effects; D012584:Sciatic Nerve / Q000166:cytology*; D019098:Telomerase / Q000235:genetics* / Q000378:metabolism; D013997:Time Factors; D014162:Transfection / Q000379:methods
D005732:Gangliosides; D005904:Glial Fibrillary Acidic Protein; D019081:O Antigens; D020800:Receptor, Nerve Growth Factor; C062875:ganglioside A2B5; D016222:Fibroblast Growth Factor 2; C509186:TERT protein, human; D019098:Telomerase