Immunity system complexity (Introduction)

by David Turell , Saturday, June 20, 2020, 16:19 (1406 days ago) @ dhw

dhw: Every disease in life’s history was once a novelty! And so (1) the immune system has had to come up with new answers every time, thus building its library of responses. […] If “all diseases can be handled by several immune systems”, how come people are still dying of cancer, flu, malaria, AIDS….? (2) Once again, I suggest the immune system does NOT contain instructions on how to counter all diseases (“anything that comes along can be dealt with by present limited responses”) but accumulates its own instructions in an ongoing learning process.

DAVID: You are close to finally understanding immunity. The first bold is correct, but unfortunately not the second. Immune cells contain all the instruction they will ever need to fight all and every infection, most with permanent blockage. There are unfortunately some viruses that constantly mutate each year […] [dhw's bold]

dhw: You agree that the immune system has built up a library of instructions to fight diseases as they have arisen. You say these instructions cover “all and every infection”, I say they don’t, and in order to prove me wrong, you provide a list of diseases for which the system does NOT contain the necessary instructions! Not for the first time, I have difficulty following your logic.

DAVID: I simply gave you a small list of strange ones the immune system has trouble with. It can handle the thousands of others by following instructions. Your bold is not correct. The immune system follows instructions, not creates them. Antibodies produced are product, nothing more.

dhw: You said my first bold was correct – see top of this post – and now you say it is not correct! If – a big but highly desirable “if” – the immune system were to find a means of killing the coronavirus, it would have added one set of instructions to those that it has already filed away in its library. Every new answer becomes part of the library which the immune system has built up with every new answer to every new problem, as you agreed first time round. And the instructions or books in the library do not cover “all and every infection”, as you have proved with your list.

The first bold is correct with the word you used 'answers'. Immune cells always follow on board instructions to create a library of answers which are remembered as antibodies or direct engulfing and digesting. In regard to corona, survivors have high level of antibodies
and their serum has been used successfully in treatment. The second bold applies only to the partially successful responses I have listed. The newborn baby come fully prepared for a lifetime fight. Colostrum is an additional advantage for those who are nursed, but unnursed babies do just as well. In AIDS the human immune system itself is destroyed by the virus. Only the new drugs help. In malaria, I'll remind you, you survived by using your immune system plus medication. But we still need a vaccine.