# Integration is an achievement, not a restored person Preclinical animal studies. Revah and colleagues transplanted human cortical organoids in vivo into the somatosensory cortex of newborn athymic rats. The grafts matured, received sensory-related input, extended projections, and contributed to experimentally studied circuits. This demonstrates a form of host–graft integration in a particular developing animal preparation. It is not a study of reversing brain death or replacing the complete brain of an adult animal. Canonical page: https://givegigs.com/wiki/necro-chapter-transplantation Last updated: 2026-11-09T18:58:11.921Z Parent topic: [necromancer-neuroscience](https://givegigs.com/wiki/necromancer-neuroscience) ## Contents - [Overview](#wiki-section-overview-1) - [Chapter notes](#wiki-section-chapter-notes-2) - [Dossier section](#wiki-section-dossier-link-3) ## Overview Preclinical animal studies. This page expands the “Integration is an achievement, not a restored person” chapter in the neuroscience collection. ## Chapter notes Revah and colleagues transplanted human cortical organoids in vivo into the somatosensory cortex of newborn athymic rats. The grafts matured, received sensory-related input, extended projections, and contributed to experimentally studied circuits. This demonstrates a form of host–graft integration in a particular developing animal preparation. It is not a study of reversing brain death or replacing the complete brain of an adult animal. For a proposed repair program, the important questions include appropriate cell identity, placement, integration, stability, and functional consequences. A graft could survive yet fail to contribute usefully. An electrical response could occur without meaningful improvement. Necromancer’s proposed milestones should therefore require both biological characterization and task-relevant evidence, with independent evaluation of adverse effects. Human neural tissue in animal hosts adds ethical questions as well as scientific opportunity. The ISSCR’s guidance calls for appropriate animal-research oversight and relevant specialist expertise for neural transplantation work. The choice of host, developmental stage, intended contribution, and monitoring should be justified for the specific question. There is no automatic ethical exemption for mouse tissue, human organoids, or small models. ## Dossier section [Open this exact section in the Necromancer dossier](/necromancer#transplantation). The original chapter status is “Preclinical animal studies.” ## Sources - [Maturation and circuit integration of transplanted human cortical organoids](https://pubmed.ncbi.nlm.nih.gov/36224417/) - [Guidelines for Stem Cell Research and Clinical Translation](https://www.isscr.org/resources/guidelines-for-stem-cell-research) --- This article is collaboratively maintained. Check the canonical page and cited sources for the latest context.