Polyamidoamine dendrimer-PEG hydrogel and its mechanical property on differentiation of mesenchymal stem cells

Article type: Research Article

Authors: Bi, Xiangdong^a; | Maturavongsadit, Panita^b | Tan, Yu^c | Watts, Morgan^a | Bi, Evelyn^d | Kegley, Zachary^a | Morton, Steve^e | Lu, Lin^b | Wang, Qian^b | Liang, Aiye^a;

Affiliations: [a] Department of Physical Sciences, Charleston Southern University, Charleston, South Carolina, USA | [b] Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina, USA | [c] Department of Bioengineering, Clemson University, Clemson, South Carolina, USA | [d] Academic Magnet High School, Charleston, South Carolina, USA | [e] Research Oceanographer National Ocean Service, Charleston, South Carolina, USA

Correspondence: [*] Corresponding authors: Xiangdong Bi, Tel.: +1 843 863 8086; Fax: +1 843 863 7290; E-mail: xbi@csuniv.edu. Aiye Liang, Tel.: +1 843 863 7833; Fax: +1 843 863 7290; E-mail: aliang@csuniv.edu

Abstract: BACKGROUND:Biocompatible hydrogel systems with tunable mechanical properties have been reported to influence the behavior and differentiation of mesenchymal stem cells (MSCs). OBJECTIVE:To develop a functionalized hydrogel system with well-defined chemical structures and tunable mechanical property for regulation of stem cell differentiation. METHODS:An in situ-forming hydrogel system is developed by crosslinking vinyl sulfone functionalized polyamidoamine (PAMAM) dendrimer and multi-armed thiolated polyethylene glycol (PEG) through a thiol-ene Michael addition in aqueous conditions. The viability and differentiation of MSCs in hydrogels of different stiffness are conducted for 21 days under corresponding induction media. RESULTS:MSCs are viable in synthesized hydrogels after 48 hours of culture. By varying the concentrations of PAMAM dendrimer and PEG, hydrogels of different gelation time and stiffness are achieved. The MSC differentiation indicates that more osteogenic differentiation is observed in hard gel (5,663 Pa) and more adipogenic differentiation is observed in soft gel (77 Pa) in addition to the differentiation caused by each individual induction media during the process of culture. CONCLUSIONS:A biocompatible in situ-forming hydrogel system is successfully synthesized. This hydrogel system has shown influences on differentiation of MSCs and may potentially be important in developing therapeutic strategies in medical applications.

Keywords: Hydrogel, PAMAM dendrimer, mesenchymal stem cells, osteogenic differentiation, adipogenic differentiation

DOI: 10.3233/BME-181037

Journal: Bio-Medical Materials and Engineering, vol. 30, no. 1, pp. 111-123, 2019