Isolation and characterization of an inhibitor of neovascularization from scapular chondrocytes.
An inhibitor of neovascularization from the conditioned media of scapular chondrocytes established and maintained in serum-free culture has been isolated and characterized. To determine whether this chondrocyte-derived inhibitor (ChDI) was capable of inhibiting neovascularization in vivo, this protein was assayed in the chick chorioallantoic membrane assay. ChDI was a potent inhibitor of angiogenesis in vivo (4 micrograms = 87% avascular zones). This inhibitor is also an inhibitor of fibroblast growth factor-stimulated capillary endothelial cell (EC) proliferation and migration, as well as being an inhibitor of mammalian collagenase. ChDI significantly suppressed capillary EC proliferation in a dose-dependent, reversible manner with an IC50 (the inhibitory concentration at which 50% inhibition is achieved) of 2.025 micrograms/ml. Inhibition by ChDI of growth factor-stimulated capillary EC migration was also observed using a modified Boyden chamber assay (IC50 = 255 ng/ml). SDS-PAGE analysis followed by silver staining of ChDI purified to apparent homogeneity revealed a single band having an M(r) of 35,550. Gel elution experiments demonstrated that only protein eluting at this molecular weight was anti-angiogenic. These studies are the first demonstration that chondrocytes in culture can produce a highly enriched, potent inhibitor of neovascularization which also inhibits collagenase.
Moses
M A
MA
Department of Surgery, Children's Hospital Medical Center, Boston, Massachusetts 02115.
Sudhalter
J
J
Langer
R
R
D000482:Allantois / Q000098:blood supply / Q000187:drug effects*; D000818:Animals; D000831:Animals, Newborn; D002356:Cartilage / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D002417:Cattle; D002642:Chick Embryo; D004305:Dose-Response Relationship, Drug; D009389:Neovascularization, Pathologic; D011506:Proteins / Q000302:isolation & purification* / Q000494:pharmacology*; D012540:Scapula / Q000166:cytology
D011506:Proteins