Abstract
The basement membrane is a specialized extracellular matrix substrate responsible for support and maintenance of epithelial and endothelial structures. Engineered basement membrane-like hydrogel systems have the potential to advance understanding of cell-cell and cell-matrix interactions by allowing precise tuning of the substrate or matrix biochemical and biophysical properties. In this investigation, we developed tunable hydrogel substrates with conjugated bioactive peptides to modulate cell binding and growth factor signaling by endothelial cells. Hydrogels were formed by employing a poly(ethylene glycol) crosslinker to covalently crosslink gelatin polymers and simultaneously conjugate laminin-derived YIGSR peptides or vascular endothelial growth factor (VEGF)-mimetic QK peptides to the gelatin. Rheological characterization revealed rapid formation of hydrogels with similar stiffnesses across tested formulations, and swelling analysis demonstrated dependency on peptide and crosslinker concentrations in hydrogels. Levels of phosphorylated VEGF Receptor 2 in cells cultured on hydrogel substrates revealed that while human umbilical vein endothelial cells (HUVECs) responded to both soluble and conjugated forms of the QK peptide, conditionally-immortalized human glomerular endothelial cells (GEnCs) only responded to the conjugated presentation of the peptide. Furthermore, whereas HUVECs exhibited greatest upregulation in gene expression when cultured on YIGSR- and QK-conjugated hydrogel substrates after 5 days, GEnCs exhibited greatest upregulation when cultured on Matrigel control substrates at the same time point. These results indicate that conjugation of bioactive peptides to these hydrogel substrates significantly influenced endothelial cell behavior in cultures but with differential responses between HUVECs and GEnCs.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 99-112 |
| Number of pages | 14 |
| Journal | Biomaterials |
| Volume | 201 |
| DOIs | |
| State | Published - May 2019 |
Funding
The authors would like to acknowledge the use of the following research facilities: the Analytical bioNanoTechnology Equipment Core Facility (ANTEC) of the Simpson Querrey Institute (SQI) at Northwestern University developed by support from the U.S. Army Research Office, the U.S. Army Medical Research and Materiel Command, and Northwestern University with ongoing support from the Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource ( NSF ECCS-1542205 ); the Electron Probe Instrumentation Center (EPIC) of Northwestern University's Atomic and Nanoscale Characterization Experimental Center (NUANCE) , which has received support from the Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF ECCS-1542205 ), the Materials Research Science and Engineering Centers (MRSECs) program (NSF DMR-1720139 ) at the Materials Research Center (MRC), the International Institute for Nanotechnology (IIN), the Keck Foundation, and the State of Illinois through the IIN; the Northwestern University Center for Advanced Microscopy (CAM) supported by NCI CCSG P30 CA060553 awarded to the Robert H. Lurie Comprehensive Cancer Center; the NUSeq Core Facility supported by the Northwestern University Center for Genetic Medicine, Feinberg School of Medicine, and Shared and Core Facilities of the University’s Office for Research; and the George M. O’Brien Kidney Research Core Center (NU GoKidney) supported by a grant from the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health under award number P30 DK114857. J.S.: Designed and performed experiments, optimized testing parameters, collected and analyzed data, and wrote and edited the manuscript including figures. S.C.S: Provided the conditionally-immortalized human glomerular endothelial cell line and contributed to experimental design. J.A.W.: Co-principal investigator who assisted with experimental design, interpretation of data, and manuscript writing and editing. R.N.S.: Co-principal investigator who assisted with experimental design, interpretation of data, and manuscript writing and editing. All authors read and approved the manuscript. This work was supported by a Ruth L. Kirschstein National Research Service Award (NRSA) Individual Predoctoral Fellowship from the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health under award number F31 DK108544 to J.S. This research was supported in part by grants from the Google Foundation (R.N.S.), the American Society of Transplantation Research Network (J.A.W.), and the McCormick Foundation (J.A.W.). This research was also supported in part by a grant from the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health under award number R01 DK113168 to J.A.W. and Merit Review I01 BX002660 from the United States Department of Veterans Affairs Biomedical Laboratory Research and Development Service to J.A.W. J.A.W. is a member of the NIDDK (Re)Building a Kidney Consortium ( U01DK107350 ). The contents presented do not represent the views of the United States Department of Veterans Affairs, the National Institutes of Health, or the United States Government. Funding sources had no involvement in study design; collection, analysis, or interpretation of data; in writing of the manuscript; or in the decision to submit the manuscript for publication.
Keywords
- Basement membrane
- Endothelial cells
- Hydrogels
- Peptides
- QK
- YIGSR
ASJC Scopus subject areas
- Mechanics of Materials
- Ceramics and Composites
- Bioengineering
- Biophysics
- Biomaterials