Amount Of Platelet-derived Growth factor-BB Research Articles

Tensile strength, growth factor content and proliferation activities for two platelet concentrates of platelet-rich fibrin and concentrated growth factor

Background/purposePlatelet-rich fibrin (PRF) can be obtained by centrifuging fresh blood in the absence of anticoagulants. Varying the centrifugation speeds may produce tougher and richer concentrated growth factors (CGF). This study examines tensile strength, growth factor content, and the potential of CGF and PRF in promoting periodontal cell proliferation. Materials and methodsBlood (40 mL/subject) was collected from 44 healthy subjects. PRF and CGF were prepared by centrifuging at 3000 rpm and switching speeds ranging within 3000 rpm, respectively. Fibrin strip was prepared and its tensile strength was measured. Transforming growth factor beta 1 (TGF-β1), platelet-derived growth factor BB (PDGF-BB), and epidermal growth factor (EGF) in the residual serum and fibrin clots were determined by enzyme-linked immunosorbent assay, and their effects on the proliferation of hFOB1.19 osteoblasts and human gingival fibroblasts were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. ResultsCompared with PRF, tensile strength of CGF was significantly higher. Concentrations and amounts of PDGF-BB and EGF in CGF were significantly higher than those in PRF. Osteoblast number was significantly higher in the cultures with fetal bovine serum (FBS, 10%) and with PRF or CGF fibrin clots (5%, 10%, and 50%) compared to that without FBS. Moreover, osteoblast number in CGF, regardless of the preparation of 10% and 50%, was significantly greater than that in PRF. Similar findings were also observed for gingival fibroblasts among the various subjects. ConclusionVarying centrifugation speeds can modify the tensile strength and biological activities of platelet fibrin clots.

Controlled Release of PDGF-bb by Coaxial Electrospun Dextran/Poly(L-lactide-co-ε-caprolactone) Fibers with an Ultrafine Core/Shell Structure

Membranes composed of dextran (DEX) and poly(L-lactide-co-ε-caprolactone) (PLCL) as ultrafine core/shell fibers for loading platelet-derived growth factor-bb (PDGF-bb) were produced by coaxial electrospinning. The morphology and core/shell structure of the DEX/PLCL fibers containing PDGF-bb were investigated by scanning electron microscopy and transmission electron microscopy. The loading amount of PDGF-bb in the DEX/PLCL membrane prepared at 0.1 ml/h of the inner solution flow rate (DEX/PLCL-1P) was much lower than that in DEX/PLCL-2P and DEX/PLCL-3P obtained at 0.2 ml/h and 0.3 ml/h inner solution flow rate, respectively. All three membranes showed obvious burst release of PDGF-bb in the first 2 days, and then the release behaviors were smoother and steadier. They all kept a fibrous morphology during the whole release period of 28 days. Studies on adhesion, proliferation and morphology of the vascular smooth muscle cells on the fibrous membranes of DEX/PLCL-1P, DEX/PLCL-2P and DEX/PLCL-3P, as well as PLCL and DEX/PLCL suggested that DEX/PLCL membranes containing PDGF-bb protected in the core of ultrafine fibers could positively promote cell attachment, and their cell activities were significantly higher than those of PLCL and DEX/PLCL membranes without PDGF-bb. The DEX/PLCL-2P membrane with fine core/shell structure of fibers would be the best choices for further applications.

The Effect of Locally Administered Anti-Growth Factor Antibodies on Neointimal Hyperplasia Formation in Expanded Polytetrafluoroethylene Grafts

The selective blockage of platelet-derived growth factor BB (PDGF-BB), basic fibroblast growth factor (bFGF), and transforming growth factor beta1 (TGF-beta1) by specific antibodies coated into expanded polytetrafluoroethylene (ePTFE) grafts may diminish neointimal hyperplasia. Sixty pigs were divided into two groups (n = 30 each) and then further divided into five subgroups. Group 1 had a bilateral iliac artery ePTFE interposition graft precoated with Matrigel. Three subgroups (A, B, and C) received a specific monoclonal antibody against PDGF-BB, bFGF, or TGF-beta1. One (D) received all antibodies, and one served as control (nonimmune immunoglobulin G [IgG] isotypes) (E). Group 2 had a bilateral iliac artery endothelial cell (EC)-seeded ePTFE interposition graft precoated with Matrigel. Three subgroups (A, B, and C) received a specific antibody against PDGF-BB, bFGF, or TGF-beta1. One (D) received all antibodies, and one served as control (nonimmune IgG isotypes) (E). Light microscopy and immunohistochemical stain showed that neointimal hyperplasia formation was significantly reduced in subgroups D compared to the others (p < 0.05). In subgroups D, the different precoating influenced neointimal hyperplasia formation. It was more pronounced in the prosthesis precoated with EC and Matrigel (p < 0.05). In organ culture, the amount of PDGF-BB, bFGF, and TGF-beta1 release was reduced in subgroup D animals compared to the others (p < 0.05). In subgroups D, the release of PDGF-BB, bFGF, and TGF-beta1 depended on ePTFE seeding. A higher amount of these growth factors was released in the prostheses precoated with EC and Matrigel (p < 0.05), and the bromodeoxyuridine labeling index confirmed higher incorporation in this subgroup (p < 0.001). The combined use of locally administered anti-PDGF-BB, bFGF, and TGF-beta1 monoclonal antibodies reduces neointimal hyperplasia formation.

Vascular cell interactions modulate the expression of endothelin-1 and platelet-derived growth factor BB.

Endothelin (ET)-1 and platelet-derived growth factor (PDGF) BB are important regulators of vascular cell growth and contractile function. We tested the hypothesis that interactions between endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) regulate the expression of these two factors. Bovine and rat cocultures of EC-VSMC that allowed cell contact and exchange of soluble mediators were studied. In bovine cocultures, ET-1 and PDGF B transcription decreased. Minimum levels of transcription were 39 +/- 9% of control for ET-1 and 31 +/- 6% of control for PDGF B. In contrast, steady-state mRNA levels transiently increased in coculture; maximum mRNA levels were 579 +/- 248 and 267 +/- 41% of control for ET-1 and PDGF B, respectively. ET-1 and PDGF BB protein levels were decreased in bovine cocultures. The amount of ET-1 in cocultures was 51% less and the amount of PDGF BB was 25% less than that in homotypic cultures. In rat cocultures, ET-1 protein levels were transiently increased compared with homotypic cultures; the maximum difference was 99 +/- 26%. These results indicate that EC-VSMC interactions regulate ET-1 and PDGF BB expression in EC-VSMC cocultures via multiple mechanisms. Furthermore, the interactive regulation appears to be species specific. These data suggest a novel mechanism for the regulation of these two vasoactive factors that may play an important role in cardiovascular physiology and/or pathology.