Characteristics of platelet gels combined with silk.
Platelet gel, a fibrin network containing activated platelets, is widely used in regenerative medicine due the capacity of platelet-derived growth factors to accelerate and direct healing processes. However, limitations to this approach include poor mechanical properties, relatively rapid degradation, and the lack of control of release of growth factors at the site of injection. These issues compromise the ability of platelet gels for sustained function in regenerative medicine. In the present study, a combination of platelet gels with silk fibroin gel was studied to address the above limitations. Mixing sonicated silk gels with platelet gels extended the release of growth factors without inhibiting gel-forming ability. The released growth factors were biologically active and their delivery was modified further by manipulation of the charge of the silk protein. Moreover, the silk gel augmented both the rheological properties and compressive stiffness of the platelet gel, tuned by the silk concentration and/or silk/platelet gel ratio. Silk-platelet gel injections in nude rats supported enhanced cell infiltration and blood vessel formation representing a step towards new platelet gel formulations with enhanced therapeutic impact.
Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, MA 02155, USA; University of Pavia, Department of Molecular Medicine, Via Forlanini 6, Pavia 27100, Italy.
Isabella
I
Pallotta
Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, MA 02155, USA.
Jonathan A
JA
Kluge
Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, MA 02155, USA.
Jodie
J
Moreau
Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, MA 02155, USA.
Rossella
R
Calabrese
Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, MA 02155, USA. Electronic address: david.kaplan@tufts.edu.
David L
DL
Kaplan
Tufts University, Department of Biomedical Engineering, 4 Colby Street, Medford, MA 02155, USA; University of Pavia, Department of Molecular Medicine, Via Forlanini 6, Pavia 27100, Italy. Electronic address: alessandra.balduini@tufts.edu.
Alessandra
A
Balduini
D000818:Animals; D001792:Blood Platelets / Q000737:chemistry*; D049109:Cell Proliferation / Q000187:drug effects; D019245:Compressive Strength / Q000187:drug effects; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005782:Gels / Q000494:pharmacology*; D061307:Human Umbilical Vein Endothelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D020935:MAP Kinase Signaling System / Q000187:drug effects; D010982:Platelet-Derived Growth Factor / Q000378:metabolism; D051381:Rats; D011923:Rats, Nude; D012212:Rheology / Q000187:drug effects; D047011:Silk / Q000494:pharmacology*; D013997:Time Factors; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
D005782:Gels; D010982:Platelet-Derived Growth Factor; D047011:Silk; D042461:Vascular Endothelial Growth Factor A; D048049:Extracellular Signal-Regulated MAP Kinases
Growth factor delivery; Platelet gel; Silk biomaterials; Silk gel