Dr. Tony Wyss-Coray

And we actually identified some.

And in mice, if we knock them out or if we neutralize them, then cognition improves in the mice, in old mice.

So there you have examples of factors and actually natural factors that can inhibit some of these detrimental factors.

But then you have also active pro-growth factors, growth factors that stimulate the activity of cells and might maintain stem cells better.

So they're truly beneficial factors, right?

The challenge in this field has been to figure out

Which ones are the most important ones?

And is there a smallest possible number of factors that you would need to have an effect, right?

Sort of a cocktail.

Now you could say our blood is nature's cocktail, right?

It's the elixir of youth.

It just sort of, or it's the fountain of youth that lives in us, but it dries out as we get older.

But it also accumulates.

There's also an accumulation of bad stuff.

So it's not just a loss of that fountain.

We have now tools where we can, in mice again, we can look at every cell in the body of a mouse and we can ask, how do the cells in an old mouse respond to young blood?

And what you see is that almost every cell changes their behavior when we measure their transcripts, so their gene expression in these cells, but they respond in different ways.

And it's expected because they have different what we call receptors.

So one cell may respond to one factor and another cell to another one.

And what's also interesting, we see a lot of stem cells.