Effects of hyaluronan and SPARC on fibroproliferative events assessed in an in vitro bladder acellular matrix model.
Bladder acellular matrix (BAM) is a promising candidate for urinary biomaterials development. In the current work we have modified the BAM construct to include two biologically active components; hyaluronan (HA) and a peptide (SP4.2) derived from secreted protein, acidic, rich in cysteine (SPARC), a matricellular glycoprotein. In order to assess the potential of an HA/SP4.2 modified BAM to influence cellular functions associated with bladder healing, experiments were conducted to evaluate the individual and combined effects of these molecules on in vitro fibroproliferative endpoints within a co-culture model. Thiol-modified HA (246 kDa, 15 mg/ml)+/-SP4.2 (200 microm) was incorporated and cross-linked into BAM disks through disulfide bond formation. The following scaffolds compositions were then evaluated in a bladder smooth muscle cell (SMC)-urothelial (UEC) cell co-culture model: BAM unmodified; BAM+HA, BAM+SP4.2 (media addition); BAM+HA+SP4.2 (media addition); BAM+HA+SP4.2 (matrix incorporated). At 3, 7 and 14 days post-seeding, SMC-mediated matrix contraction and gelatinolytic activity were evaluated. HA-modified BAM exhibited a significantly higher degree of contraction and gelatinase activity compared to unmodified BAM. In contrast, addition of SP4.2 to BAM produced a negligible effect on contraction, while significantly reducing gelatinase activity. Matrices containing both molecules displayed significant increases in contraction, while gelatinase activity was dependent upon the method of peptide delivery. These results demonstrate that both HA and SP4.2 have significant, yet distinct effects on the contractile and proteolytic activity of bladder SMCs and suggest that a modified BAM may be capable of modulating processes associated with post-surgical graft contracture and scar formation.
Department of Chemical Engineering and Applied Chemistry, Institute for Biomaterials and Biomedical Engineering, University of Toronto, 200 College Street, Toronto, Ont., Canada M5S 3E5.
Allison L
AL
Brown
Murice J
MJ
Ringuette
Glenn D
GD
Prestwich
Darius J
DJ
Bagli
Kimberly A
KA
Woodhouse
D016475:3T3 Cells; D000818:Animals; D018929:Cell Culture Techniques; D049109:Cell Proliferation; D002478:Cells, Cultured; D005109:Extracellular Matrix / Q000737:chemistry / Q000378:metabolism*; D018093:Gelatinases / Q000378:metabolism; D006820:Hyaluronic Acid / Q000378:metabolism*; D051379:Mice; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000378:metabolism; D015676:Osteonectin / Q000378:metabolism*; D010455:Peptides / Q000378:metabolism; D012038:Regeneration; D013552:Swine; D023822:Tissue Engineering / Q000379:methods*; D001743:Urinary Bladder / Q000166:cytology / Q000378:metabolism*
D015676:Osteonectin; D010455:Peptides; D006820:Hyaluronic Acid; D018093:Gelatinases