James P. Allison

But anyway, evolutionarily, this other system came along, which we call the adaptive immune system, where you actually have receptors that are made by random recombination of DNA sequences. I don't want to go into the details, but basically essentially random processes that give you a random set of different receptors. It's been calculated...

But anyway, evolutionarily, this other system came along, which we call the adaptive immune system, where you actually have receptors that are made by random recombination of DNA sequences. I don't want to go into the details, but basically essentially random processes that give you a random set of different receptors. It's been calculated...

that you can make all things if you had full ability to make every receptor that can be made with the structures that are in there. It's really a fascinating area of biology and its own, but it's 10 to the 15th, maybe 10 to the 17th power. Yeah. You only have about 10 to the 10th cells, 10 to the 12th cells.

that you can make all things if you had full ability to make every receptor that can be made with the structures that are in there. It's really a fascinating area of biology and its own, but it's 10 to the 15th, maybe 10 to the 17th power. Yeah. You only have about 10 to the 10th cells, 10 to the 12th cells.

So it's a thousand times more cells than total cells, at least a thousand times more total cells than you have in your body. So each of us really realized only a fraction of the possible diversity of different T cell receptors that could be made. in your body, to the species. So the population is protected, probably, but not the individual, necessarily.

So it's a thousand times more cells than total cells, at least a thousand times more total cells than you have in your body. So each of us really realized only a fraction of the possible diversity of different T cell receptors that could be made. in your body, to the species. So the population is protected, probably, but not the individual, necessarily.

No, they're generated essentially randomly. Okay. The cells come out of the bone marrow. For T cells, they come out of the bone marrow. They go to this organ called the thymus, which sits right above the heart. And there they start developing from this precursor stem cell into functional T cells by random rearrangements. And they're put together.

No, they're generated essentially randomly. Okay. The cells come out of the bone marrow. For T cells, they come out of the bone marrow. They go to this organ called the thymus, which sits right above the heart. And there they start developing from this precursor stem cell into functional T cells by random rearrangements. And they're put together.

And there's this fascinating testing system where there's a scaffold on cells that presents the antigens, which are little bits of protein. There are only eight to 10 amino acids, eight to 12 maybe amino acids long that are presented in the surface of this thing. It looks like a hot dog bun. And it's got a peptide in the middle of it.

And there's this fascinating testing system where there's a scaffold on cells that presents the antigens, which are little bits of protein. There are only eight to 10 amino acids, eight to 12 maybe amino acids long that are presented in the surface of this thing. It looks like a hot dog bun. And it's got a peptide in the middle of it.

There's a peptide for virtually every protein that's made in your body. It'll bind there and will be put on the surface of your cells so the immune system knows a sample of everything that's going on in the cell. even if the thing normally wouldn't be on the cell surface.

There's a peptide for virtually every protein that's made in your body. It'll bind there and will be put on the surface of your cells so the immune system knows a sample of everything that's going on in the cell. even if the thing normally wouldn't be on the cell surface.

If it's a virus that's just infected a cell and the cell starts making bits of virus, I mean, making the parts of the virus that it needs to reproduce and go out and infect other cells, as they're making it, those proteins will be cut into little pieces and pieces that will be put on the surface. And if the right T cell comes by and says, whoops, that shouldn't be there, it'll kill it.

If it's a virus that's just infected a cell and the cell starts making bits of virus, I mean, making the parts of the virus that it needs to reproduce and go out and infect other cells, as they're making it, those proteins will be cut into little pieces and pieces that will be put on the surface. And if the right T cell comes by and says, whoops, that shouldn't be there, it'll kill it.

It's essentially random.

It's essentially random.

Exactly. But you got to get rid. A lot of those are going to be harmful. They may be harmful. And so they got the tumor. I mean, the thymus not only educates the cells as to which ones can be useful, but gets rid of the ones which will hurt you, hopefully. If they don't, you end up with diabetes or you end up with...

Exactly. But you got to get rid. A lot of those are going to be harmful. They may be harmful. And so they got the tumor. I mean, the thymus not only educates the cells as to which ones can be useful, but gets rid of the ones which will hurt you, hopefully. If they don't, you end up with diabetes or you end up with...

know different autoimmune syndromes and stuff that's right sorry these are t cells that can be dangerous if they're not in the right kind yeah if they're autoreactive they react with self-protein or sometimes if a virus comes in and tricks the immune system into thinking something's foreign when it's closely enough to a self thing occasionally you'll get a spillover uh can be damaged uh like for measles and stuff

know different autoimmune syndromes and stuff that's right sorry these are t cells that can be dangerous if they're not in the right kind yeah if they're autoreactive they react with self-protein or sometimes if a virus comes in and tricks the immune system into thinking something's foreign when it's closely enough to a self thing occasionally you'll get a spillover uh can be damaged uh like for measles and stuff