I have recently been doing a lot of research into the interplay between the inna
ID: 30938 • Letter: I
Question
I have recently been doing a lot of research into the interplay between the innate and adaptive immune systems in humans, and mammalian laboratory models. This has led to my reading some interesting information on the immune response in insects;
Insects have a highly efficient immune system. In response to a bacterial attack, their fat body (the equivalent of the liver in mammals) synthesizes a whole range of peptides with an antibacterial and antifungal effect.
This fascinated me, as the clear inference is that there are no
Explanation / Answer
Immunity has probably evolved more than once as it is completely necessary for survival. You might even argue that defenses such as antibiotics and predatory behavior are immune defenses for single celled creatures.
As you point out, plants have a different immune system than animals do. Insects do too. They don't have innate immune memory which many animals have, where pools of cells embody the immune response to a specific antigen. (i.e. encode for a specific immunoglobin or a tCell Receptor variant).
I found this reference that this appears to be the collective property of jawed vertebrates. Even so, there are many late innovations in the immune system, where reptilian and mammalian immune responses vary substantially.
Its not clear to me whether other animals have the insect system. Animals that branched off before insect lines such as radiates probably have their own way of dealing with immune response. That's just a guess though.