Soft tissue reaction to microgrooved poly-L-lactic acid implants loaded with transforming growth factor beta(3).
In both normal and disturbed wound healing, the generation of large, contracting scars can raise serious functional and cosmetic problems. A possible strategy to minimize or avoid the generation of scar tissue surrounding an implant is to apply transforming growth factor-beta(3) (TGF-beta(3)) to the implant. TGF-beta(3) (0, 1, or 2.5 microg) was freeze-dried onto poly-L-lactic acid (PLA) microgrooved substrates (width, 10 microm; depth, 1 microm) and implanted subcutaneously on the backs of rats for 2 and 8 weeks. After sacrifice, implants and surrounding tissue were histologically processed. Light microscopic and histomorphometric evaluation of capsule thickness, capsule quality, and implant-tissue interface was performed. In addition, we stained for alpha-smooth muscle actin (SMA), collagen, and ED-1 (a monocyte-macrophage marker). All implants were surrounded by a fibrous capsule. Capsules of the implants loaded with 1 or 2.5 microg of TGF-beta(3) showed significantly higher capsule quality. This meant that capsules were more mature compared with implants without TGF-beta(3). However, no significant differences were found in terms of thickness of the capsules or quality of the interface. Finally, apparently significant differences were also found in the expression of alpha-SMA, when comparing the various growth factor concentrations at both implantation points. In conclusion, the use of microgrooved PLA substrates with TGF-beta(3) did not lead to an overall improvement of periimplant tissue healing.
Parker
J A T C
JA
Department of Biomaterials, University Medical Center Nijmegen, College of Dental Science, Nijmegen, The Netherlands.
Walboomers
X F
XF
Von Den Hoff
J W
JW
Maltha
J C
JC
Jansen
J A
JA
D000199:Actins / Q000378:metabolism; D000818:Animals; D003094:Collagen / Q000378:metabolism; D019344:Lactic Acid / Q000378:metabolism*; D008264:Macrophages / Q000378:metabolism; D008297:Male; D011091:Polyesters; D011108:Polymers / Q000378:metabolism*; D019736:Prostheses and Implants; D051381:Rats; D017208:Rats, Wistar; D016212:Transforming Growth Factor beta / Q000378:metabolism*; D053782:Transforming Growth Factor beta3; D014945:Wound Healing / Q000502:physiology
D000199:Actins; D011091:Polyesters; D011108:Polymers; C509046:Tgfb3 protein, rat; D016212:Transforming Growth Factor beta; D053782:Transforming Growth Factor beta3; D019344:Lactic Acid; C033616:poly(lactide); D003094:Collagen