Dr. Sergiu Pașcă

And then around that time, we got a piece of tissue that was removed from a child who underwent surgery for epilepsy.

So when you sometimes have to undergo the surgeries, intractable epilepsy is really severe.

Maybe you talked about this previously.

You have to remove some tissue.

And when you remove some of that tissue, you also have to remove some healthy tissue.

And so we got some of that healthy tissue.

And of course, we're always eager to understand how the cells that were made in a dish are similar or dissimilar to the ones in the actual brain.

We still need to benchmark before we use that for a therapy or for anything else.

And we compare one day some of the cells.

And we realize, to our amazement,

I don't know how we'd never notice it or nobody has really like made a big deal out of it, but the neurons that we're making in the dish were about 10 times smaller than the ones in the cortex on average.

I mean, there are kind of like miniature versions of what was happening.

And so it was like, of course, immediately it was like, what is happening in vivo?

You know, is there something, you know, as they say, in vivo veritas, very often, right?

We know this has been the case for immunology, that many experiments in vitro have not always panned once you actually study them in an actual patient.

So that's when we actually started to also use transplantation, meaning we started thinking, could we actually put some of the cells in an animal

and see whether they acquire new properties or they look much more like this.

And of course, transplantation has been used for four years.

Many of these experiments were done before I was born, especially in Sweden, when scientists will actually take various cells and transplant them into animals.

And so what we did, we started doing, is like taking actual organoids, cortical organoids, and then transplanting them into a rat, a early born rat,