Complex interactions at graft-tissue interfaces reviewed

Grafting engineered tissue involves complex biological interactions at the interface, and a thorough understanding of these interactions is crucial to mitigate negative side effects post-implantation. Many of these side-effects can be avoided by careful implantation management and control of interactions at the interfaces. Zhu et al. provide a review of these interactions, post-implantation reactions and tactics for ensuring the success of grafting engineered tissues.

The review summarizes existing research on the interactions at graft-tissue interfaces from biochemical, cellular and system biological perspectives, including the mechanisms that dominate specific reactions at the interface between engineered materials and biological cells.

“Oscar Wilde says, ‘The truth is rarely pure and never simple.’ This is particularly true for tissue-engineered product of joint cartilage,” author Dongan Wang said. “As native articular hyaline cartilage is an elegant tissue free of impurities or scars, our man-made cartilage product has to be no less pure than its native counterpart. The high purity of products, in terms of both composition and phenotype, poses the greatest challenge and critically relies on good control of interactions at the cell-biomaterial interface.”

According to their analysis based on the existing literature, decellularized biological grafts may hold the key to avoiding negative post-implantation responses of implants – with or without pre-seed cell populations. They suggest that future implants should utilize surface modifications or functionalization techniques to ensure bioactivity, rather than relying on unmodified biomaterials.

“Given the high complexity, uncertainty and initiative of biological systems, further development of tissue engineering seems to be better centered on biological side of the interface with engineered biomaterials,” said Wang.

Source: “Interactions at engineered graft-tissue interfaces: A review,” by Wenzhen Zhu, Xiaolei Nie, Qi Tao, Hang Yao, and Dongan Wang, APL Bioengineering (2020). The article can be accessed at https://doi.org/10.1063/5.0014519 .