James Smith

Yeah, that's pretty much right.

So the innate immune system, one way to think about it is the first line of defense, and it works by recognizing patterns that are common to pathogens.

So, for example, it recognizes bacterial DNA.

All bacteria have bacterial DNA.

It recognizes lipopolysaccharide, which is really common kind of on the surface of bacteria.

Adaptive immunity is kind of a specialized defense.

In theory, it can mount a response to any arbitrary invader.

So you have antibodies that have so much diversity that they can basically bind to any potential surface, including actually to mirror proteins.

Some of the key cells in adaptive immunity to be aware of are T cells and B cells.

So for most vertebrates have immune systems that are quite similar to human immune systems.

So the last common ancestor of the vast majority of vertebrates that are alive today had an innate immune system that has the characteristics that we talked about with pattern recognition receptors that play a key role and had adaptive immunity based on T and B cells.

So that means that the deficiencies

that we're expecting in humans are likely to be applicable to a lot of other animals as well.

But there is diversity in animals, so I don't think this is universally going to be the case.

Some of them will have different susceptibility.

The Atlantic cod, for example, the Atlantic cod has lost the ability to present antigens via MHC class two, and instead has an expanded set of these pattern recognition receptors.

And the zebrafish, which is a really commonly studied model organism for developmental biology, has like 10 times the number of nod-like receptors, which are a type of pattern recognition receptor, than humans and mice.

And most of these receptors are not characterized, so we don't know what they bind to.

And they might bind to achiral things.

And more generally, I think...