[Ectopic osteogenesis of tissue engineered bone with slow-released bioactive factors].
OBJECTIVE
To study the ectopic osteogenesis of tissue engineered bone with recombinant human bone morphogenetic protein/transforming growth factor-beta (rhBMP/TGF-beta) or WO-1 slow-released factors.


METHODS
Partial demineralized freeze-dried bone (PDFDB) of pig was used as scaffold material. rhBMP/TGF-beta or WO-1 were pre-coated on the surface of material by means of vacuum negative pressure absorption, and then coated with polylactic acid (PLA) to make slow-released material. There were six group: PDFDB material (group A); PDFDB combined with osteoblasts (group B); PDFDB material with rhBMP/TGF-beta slow-released system (group C); PDFDB material combined with rhBMP/TGF-beta slow-released system osteoblasts (group D); PDFDB with WO-1 slow-released system (group E); PDFDB material combined with WO-1 slow-released system and osteoblasts (group F) were implanted in bilateral lower limbs of 36 Newzealand rabbits respectively (6 rabbits in each groups). Histological, histochemical and biochemical analysis were detected 2, 4, 6, 8 weeks after operation.


RESULTS
Within the observation periods, no osteogenesis was observed in group A. The osteogenesis in group B, D, F were superior to that of group C and E (P < 0.05). The osteogenetic activity in group C and E was delayed. The quantity and quality of osteogenesis in group D and F were 2 weeks ahead of time compared with group B, and 4 weeks to that of group C and E. The newborn calcification content was superior to that of group A, C, and E (P < 0.05).


CONCLUSIONS
The osteogenesis of PDFDB materials with BMP/TGF-beta or WO-1 is slower than that of which combined with osteoblasts. Simple material PDFDB has no ectopic osteogenesis.
Yang
Zhi-ming
ZM
Institute of Reparative and Reconstructive Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China. orthop@public.cd.sc.cn
Li
Yu-biao
YB
Qin
Ting-wu
TW
Xie
Hui-qi
HQ
Li
Xiu-qun
XQ
Liu
Jun
J
Zhao
Jin-mei
JM
D000818:Animals; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology*; D018786:Bone Substitutes / Q000494:pharmacology*; D002648:Child; D004357:Drug Synergism; D005260:Female; D006801:Humans; D019344:Lactic Acid / Q000494:pharmacology; D010012:Osteogenesis / Q000187:drug effects*; D011091:Polyesters; D011108:Polymers / Q000494:pharmacology; D011817:Rabbits; D011994:Recombinant Proteins / Q000494:pharmacology; D013552:Swine; D023822:Tissue Engineering; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
D019485:Bone Morphogenetic Proteins; D018786:Bone Substitutes; D011091:Polyesters; D011108:Polymers; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; D019344:Lactic Acid; C033616:poly(lactide)