Saliva is an ultrafiltrate of plasma (speaking with my biochemist hat one). In other words, whatever is in saliva is also in blood/plasma (including ingested drugs - you can do a drug test on saliva same as you could on blood, though blood is much more pleasant to work with) and will find its way to the cells via their blood supply. I am skeptical of this report without knowing a lot more about it.
I really wish more people would take your approach....including the writers of these type press releases......
This is the same as mother's milk. Just ask me how much I had to watch my own diet extremely carefully while nursing my allergic-to-cows-dairy child! The cows milk protein ended up in my milk, which caused problems for my child. And yes, I would believe this about saliva. C'mon. What goes in comes out, yes?