[Stretch growth of integrated axon tracts: Extremes and exploitations](https://pmc.ncbi.nlm.nih.gov/articles/PMC3019093/) (2011) [Tissue-engineered grafts exploit axon-facilitated axon regeneration and pathway protection to enable recovery after 5-cm nerve defects in pigs](https://pmc.ncbi.nlm.nih.gov/articles/PMC9635828/) (2022) "have previously developed tissue engineered nerve grafts (TENGs) through the process of axon stretch growth. TENGs consist of living, centimeter-scale, aligned axon tracts that accelerate axon regeneration at rates equivalent to the gold standard autograft in small and large animal models of PNI, by providing a newfound mechanism-of-action referred to as axon-facilitated axon regeneration (AFAR). To enable clinical-grade biomanufacturing of TENGs, a suitable cell source that is hypoimmunogenic, exhibits low batch-to-batch variability, and able to tolerate axon stretch growth must be utilized. To fulfill these requirements, a genetically engineered, FDA-approved, xenogeneic cell source, GalSafeĀ® neurons, produced by Revivicor, Inc., have been selected to advance TENG biofabrication for eventual clinical use." See [[neurosurgery]], [[organoids]]