title: Protein-loaded PLGA-PEG-PLGA microspheres: a tool for cell therapy.
abstract: A promising strategy to repair injured organs is possible by delivering a growth factor via poly-(d,l lactide-co-glycolide) (PLGA) microspheres; the latter are coated with adhesion molecules that serve as a support for cell delivery. At present, PLGA is not the optimal choice of polymer because of poor or incomplete protein release. The use of a more hydrophilic PLGA-PEG-PLGA (A-B-A) copolymer increases the degree of protein release. In this work, the impact of different combinations of (B) and (A) segments on the protein-release profile has been investigated. Continuous-release profiles, with no lag phases, were observed. The triblock ABA with a low molecular weight of PEG and a high molecular weight of PLGA showed an interesting release pattern with a small burst (<10% in 48 h) followed by sustained, protein release over 36 days. Incomplete protein release was found to be due to various causes: protein adsorption, protein aggregation and protein denaturation under acidic conditions. Interestingly, cell viability and cell adhesion on microspheres coated with fibronectin highlight the interest of these polymers for tissue engineering applications.
authors.affiliation: LUNAM Université, Ingénierie de la Vectorisation Particulaire, F-49933 Angers Cedex, France.
authors.forename: Van-Thanh
authors.initials: VT
authors.lastname: Tran
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Karam
authors.forename: Xavier
authors.initials: X
authors.lastname: Garric
authors.forename: Jean
authors.initials: J
authors.lastname: Coudane
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Benoît
authors.forename: Claudia N
authors.initials: CN
authors.lastname: Montero-Menei
authors.forename: Marie-Claire
authors.initials: MC
authors.lastname: Venier-Julienne
mesh_terms: D000327:Adsorption; D040761:Biomimetic Materials / Q000737:chemistry* / Q000378:metabolism; D001854:Bone Marrow Cells / Q000166:cytology* / Q000378:metabolism; D002448:Cell Adhesion; D002470:Cell Survival; D002478:Cells, Cultured; D005353:Fibronectins / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D008863:Microspheres; D008970:Molecular Weight; D020442:Poloxamer / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry* / Q000378:metabolism; D011098:Polyglactin 910 / Q000737:chemistry* / Q000378:metabolism; D011489:Protein Denaturation; D012995:Solubility; D017154:Stromal Cells / Q000166:cytology* / Q000378:metabolism; D013499:Surface Properties; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D005353:Fibronectins; C528571:poly(lactic-co-glycolic acid)-polyethylene glycol-poly(lactic-co-glycolic acid); D020442:Poloxamer; D011098:Polyglactin 910; D011092:Polyethylene Glycols