Steroidogenic properties of a spontaneously established porcine granulosa cell line (PGC-2).
A spontaneously established porcine granulosa cell line (PGC-2) was cloned through the continuous culturing of primary granulosa cells collected from equine chorionic gonadotropin (eCG)-treated prepubertal gilts. This established cell line has undergone approximately 100 passages and shows contact-inhibition of growth. PGC-2 stained with a monoclonal antibody (mAb) directed against cytokeratin, indicating its epithelial nature, but not with a mAb directed against vimentin, suggesting that it is not fibroblast-derived. Immunoblotting revealed that PGC-2 expresses cadherin, an epithelial Ca+2-dependent cell adhesion molecule. The cells were dependent on serum for growth and had a doubling time of approximately 20 hr when cultured with 10% fetal bovine serum. The cell line was examined for the presence of FSH receptors, cAMP responses, and steroidogenic capabilities. The cell line lacks FSH receptors as assessed by radiolabelled-ligand binding, and no transcripts for FSH receptor were detected by Northern blotting of total cellular RNA. Neither FSH nor cholera toxin (0.5 ng/mL) stimulated increases in cAMP levels in these cells, whereas forskolin (10 microM) induced a fivefold increase in cAMP production. When a higher concentration of cholera toxin (300 ng/mL) was used, however, cAMP levels doubled by 2 hr. Despite a lack of responsiveness to purified of SH or oLH, the cells were capable of progesterone and estradiol production when provided with the appropriate substrates. We conclude that PGC-2 display properties that are similar to immature granulosa cells and may provide a suitable in vitro model for the study of granulosa cell function.
Department of Animal Science, McGill University, Quebec, Canada.
I
I
Kwan
R
R
Farookhi
H T
HT
Huynh
B D
BD
Murphy
J D
JD
Turner
B R
BR
Downey
D000818:Animals; D002455:Cell Division; D002460:Cell Line; D000242:Cyclic AMP / Q000378:metabolism; D004958:Estradiol / Q000096:biosynthesis; D005260:Female; D006107:Granulosa Cells / Q000166:cytology / Q000378:metabolism*; D010641:Phenotype; D011374:Progesterone / Q000096:biosynthesis; D011962:Receptors, FSH / Q000235:genetics / Q000378:metabolism; D013552:Swine
D011962:Receptors, FSH; D011374:Progesterone; D004958:Estradiol; D000242:Cyclic AMP