Functional hepatocyte clusters on bioactive blend silk matrices towards generating bioartificial liver constructs

Assessing the compatibility of primary human hepatocyte culture within porous silk sponges

“…28 Silk scaffolds have been previously used for hepatocyte culture with positive functional and implantation outcomes. Specically, primary rat hepatocytes seeded onto silk/chitosan scaffolds showed reduced inammatory response relative to synthetic scaffolds; 29 rat hepatocytes seeded onto silk/RGD scaffolds demonstrated improved gene expression for 3+ weeks over 2D culture; 30 co-cultures of rat hepatocytes and stellate cells in silk scaffolds demonstrated improved functions for 2 weeks than hepatocyte monocultures. 31 In human-relevant studies, the QZG human hepatic cells seeded onto silk/gelatin scaffolds demonstrated inltration of host cells aer implantation into a rodent model, 32 and cancerous HepG2 cells seeded onto silk/RGD scaffolds demonstrated improved gene expression over 2D culture.…”

“…31 In human-relevant studies, the QZG human hepatic cells seeded onto silk/gelatin scaffolds demonstrated inltration of host cells aer implantation into a rodent model, 32 and cancerous HepG2 cells seeded onto silk/RGD scaffolds demonstrated improved gene expression over 2D culture. 30 While the studies above are promising for the use of silk/protein scaffolds for hepatocyte culture in vitro and implantation in vivo in animal models, the application of such scaffolds for long-term (1+ month) PHH cultures AE supportive non-parenchymal cells (NPC) has yet to be realized. Therefore, here we sought to determine the functional behavior of PHHs within porous silk sponges (scaffolds) incubated with type I collagen during different steps of scaffold processing.…”

Primary Human Hepatocytes Maintain Long-term Functions in Porous Silk Scaffolds Containing Extracellular Matrix Proteins

“…Previous investigations using silk scaffolds using either gelatin or RGD as integrin binding sites for culture of human liver cell lines (i.e., HepG2 cell line) or rodent hepatocytes have shown minimal inflammation and no adaptive immune response or fibrosis upon implantation into rodents models [23,26]. While it is difficult to fully extrapolate these studies to our work due to the use of different cell types, these previous studies nonetheless show that implanting liver constructs made of silk/ECM scaffolds has promise as a potential therapy that needs further exploration.…”

“…Furthermore, silk degradation into non-toxic byproducts in vivo can be extended for months to allow native tissue remodeling. While silk scaffolds, in some cases with incorporated ECM proteins/gels, have been used to generate long-term tissue constructs for several different tissue types [20,22] as well as for the culture of rat hepatocytes +/-hepatic stellate cells for 2-3 weeks [23][24][25][26], it is not clear if silk scaffolds can support long-term PHH functions. Therefore, here we sought to determine for the first time the long-term function of PHHs in porous silk scaffolds +/-type I collagen.…”

Microscopic considerations for optimizing silk biomaterials

“…The presence of RGD (arginine-glycine-aspartic acid), a cell adhesion protein found within many matrix proteins, in nonmulberry silk sourced from Antheraea pernyi, Antheraea yamamai, and Antheraea mylitta silkworms make it an attractive regenerative option (Kundu et al, 2012). Nonmulberry silk has been used in silk scaffolds for different tissues, such as articular cartilage (Talukdar, Nguyen, Chen, Sah, & Kundu, 2011) and liver tissue (Janani, Nandi, & Mandal, 2017). Research has also been done to determine the properties of blended mulberry and nonmulberry silk.…”