A standardized protocol of constructing individual tissue-engineered grafts for treating bone defect.

Patient-specific individual tissue-engineered bones (iTEBs) have been recognized as a promising strategy for treating large bone defects. However, current construction protocols of iTEBs vary between lots, lack standardization and quality control, hampering further research and application. This study was aimed to detail a standardized constructing protocol for iTEBs, which can be used for both clinical and experimental purposes. The procedure was designed and described as follows: scaffold preparation, cell isolation and culture, and fabrication of iTEBs. Manipulation and caution points in each section were detailed. A series of scales on the quality control and safety monitoring was developed. The effectiveness and safety of iTEBs were evaluated. Eventually, the preparing portion, from cell culture to scaffold treatment, usually required 21 days. Generally, the fabrication section took 5 days. The main advantage of this protocol was that each step was standardized and quality controlling and safety monitoring were performed throughout the process to ensure the homogeneity, reliability and safety. The resulting iTEBs were effective and applicable to both clinical and experimental purposes. Thus, we have established a refined and standardised protocol detailing the construction process of patient-specific iTEBs that comply with strict quality control and safety criteria. This protocol is relatively easy for graduate students or staff working in the field of bone tissue engineering to implement.