Identification of a PDGF-like mitoattractant produced by NIH/3T3 cells after transformation with SV40
✍ Scribed by Ilan Bleiberg; Anita K. Harvey; Georgeann Smale; Gary R. Grotendorst
- Publisher
- John Wiley and Sons
- Year
- 1985
- Tongue
- English
- Weight
- 643 KB
- Volume
- 123
- Category
- Article
- ISSN
- 0021-9541
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
It has previously been shown that fibroblastic cells transformed by SV40 exhibit a reduced requirement for PDGF for growth. In addition, NIH/3T3 cells lose both their chemotactic response to PDGF and specific cell surface binding of PDGF after transformation with SV40. We have now examined whether the SV40 transformed NH/3T3 cells are producing a factor which acts similarly to PDGF. Our studies indicate that NIH/3T3 cells transformed with SV 40 produce a factor which shares many biological properties with PDGF. We were unable to detect this activity in conditioned media from non‐transformed NIH/3T3 cells. The SV40/NIH/3T3 derived factor appears to possess both chemotactic and mitogenic activity for connective tissue cells but not endothelial or epithelial cells. Furthermore, in preliminary studies, this activity competes with ^125^I‐PDGF for binding to smooth muscle cells. The biochemical properties of the SV40/NIH/3T3 derived factor are different from those of PDGF. The SV40 activity appears to reside in a heat labile acidic protein (pI < 7.0) of MW < 30,000 whereas PDGF is a heat stable basic protein (pI9.8) of 30,000 MW. Production of this factor may play a role in the decreased serum requirement for cell replication exhibited by SV40‐transformed NIH/3T3 cells by supplying the cells with their own PDGF‐like growth factor.