Park Honghyun, Kang Sun-Woong, Kim Byung-Soo, Mooney David J, Lee Kuen Yong
Department of Bioengineering, College of Engineering, Hanyang University, Seoul 133-791, Republic of Korea.
Macromol Biosci. 2009 Sep 9;9(9):895-901. doi: 10.1002/mabi.200800376.
Injectable delivery vehicles in tissue engineering are often required for successful tissue formation in a minimally invasive manner. Shear-reversibly crosslinked hydrogels, which can recover gel structures from shear-induced breakdown, can be useful as an injectable, because gels can flow as a liquid when injected but re-gel once placed in the body. In this study, injectable and shear-reversible alginate hydrogels were prepared by combination crosslinking using cell-crosslinking and ionic crosslinking techniques. The addition of a small quantity of calcium ions decreased the number of cells that were required to form cell-crosslinked hydrogels without changing the shear reversibility of the system. The physical properties and gelation behavior of the gels were dependent on the concentration of both the cells and the calcium ions. We found that gels crosslinked by combination crosslinking methods were effective to engineer cartilage tissues in vivo. Using both ionic and cell-crosslinking methods to control the gelation behavior may allow the design of novel injectable systems that can be used to deliver cells and other therapeutics for minimally invasive therapy, including tissue engineering.
组织工程中的可注射递送载体通常对于以微创方式成功形成组织是必需的。可从剪切诱导的破坏中恢复凝胶结构的剪切可逆交联水凝胶可用作可注射材料，因为凝胶在注射时可作为液体流动，但一旦置于体内就会重新凝胶化。在本研究中，通过使用细胞交联和离子交联技术的组合交联制备了可注射且剪切可逆的藻酸盐水凝胶。添加少量钙离子减少了形成细胞交联水凝胶所需的细胞数量，而不改变系统的剪切可逆性。凝胶的物理性质和凝胶化行为取决于细胞和钙离子的浓度。我们发现通过组合交联方法交联的凝胶在体内对工程化软骨组织有效。使用离子和细胞交联方法来控制凝胶化行为可能允许设计新型可注射系统，其可用于递送细胞和其他治疗剂以进行微创治疗，包括组织工程。
