However, there's no mention whatsoever about N-Acetyl Cysteine
You can read more about glycosacharides such as that at this site (automatic PDF download)
A good thing that I read was they were touting cat's claw. I have a cat and she has all her claws, so I should be good to go in that regard. And she knows that she gets clipped every once in a while. I'm not clear what you're supposed to do with 'em though. Do you smoke 'em or something?
I've read multiple discussions on this, pro and con. On the con side, yes, they do stimulate the immune system and may increase the ability to produce cytokines as well. On the other hand, elderberries can decrease the total viral load that gets into the system, and can prevent replication of the virus in a host cell, thus keeping immune reaction lower than without elderberries.
So this is a judgement call that everyone has to make for themselves about any natural antiviral, including even garlic.
Personally, I take elderberry tonic, that I have made myself, a tablespoon in the morning and one at night. I have opted FOR the elderberries, since they reduce total viral load in Israeli research, and prevent or reduce viral replication once in the body. It's my thinking that will reduce the body's immune response.
Truthfully, at this point we don't know.