A research team led by scientists at Cincinnati Children's Hospital in the United States has successfully developed the world's first human "mini" brain containing a fully functional blood-brain barrier. This achievement holds promise for advancing scientists' understanding of various brain disorders and improving treatment methods for conditions such as stroke, cerebrovascular diseases, brain cancer, Alzheimer's disease, Huntington's disease, Parkinson's disease, and other neurodegenerative disorders. The related paper was published in the latest issue of the journal Cell Stem Cell.
The process of forming human brain-like organs containing the blood-brain barrier involves the fusion of two types of organs.
Source: Cell Stem Cell
Blood vessels in the brain are covered by a layer of tightly packed cells, forming the blood-brain barrier. This barrier strictly limits the size of molecules entering the central nervous system from the blood. A properly functioning blood-brain barrier effectively blocks harmful substances while allowing essential nutrients to enter the brain, maintaining brain health. However, it also hinders many potentially beneficial drugs from reaching the brain. Moreover, developmental defects or breaches in the blood-brain barrier can lead to or exacerbate various neurological disorders.
Previously, no research team had successfully created a fully functional human brain vascular barrier within brain-like organs. In a recent study, scientists successfully fused a brain-like organ with a diameter of 3-4 millimeters with a vascular-like organ with a diameter of approximately 1 millimeter, forming a sphere slightly over 4 millimeters in diameter (about the size of a sesame seed). This novel structure is referred to as a "Blood-Brain Barrier (BBB) Assembloid."
Cultivated from stem cells of specific brain disorder patients, this assembloid can reflect conditions such as gene mutations that may lead to dysfunction of the blood-brain barrier. By utilizing stem cells from these patients, the research team successfully constructed assembloids that accurately replicate key features of cerebral cavernous malformations, offering a fresh perspective for exploring the molecular and cellular pathophysiology of this brain disorder.
The research team believes this model holds broad application prospects: tailoring treatment plans based on patients' unique genetic and molecular characteristics; modeling various neurovascular diseases; analyzing more accurately and rapidly whether potential brain drugs can effectively cross the blood-brain barrier; and supporting immune-based therapies for the brain.
