Using human induced pluripotent stem cells (hiPSC) to create organoids is becoming a powerful tool for studying brain development and dysfunction.
However, it is not proven whether the organoid can be functionally connected to the sensory network in the human body.
Recently, a study published in Nature Communications showed that after transplanting a human brain-like organ into mice, the organ-like organ made a functional connection to the mouse cerebral cortex and responded to light.
The team placed an array of electrodes made of transparent graphene on top of the implanted cortical analogs to record the neural activity of the implanted analogs and the host cortex in real time.
Using two-photon imaging, the scientists observed that the blood vessels of the mice had opened up like an organoid, supplying nutrients and oxygen to the implants.
After three weeks of implantation, the researchers used flashing white LEDs in front of the mice to observe the responses of different brain cells.
It was found that the graphene electrode showed a distinct spike signal coming from the visual cortex.
Experiments have shown that the organoid responds to stimuli in the same way as the surrounding mouse brain tissue.
The organoid has established a functional connection with the host brain tissue.
Follow-up experiments over 11 weeks have shown that the implanted human “mini-brains” are becoming increasingly integrated into their hosts functionally.
Next, scientists hope to use this technique to simulate the progression of neurological diseases.