Yes, as some guys already mentioned: it's a new field, there is evidence, but no clear picture as to how far the manipulation/stimulation works.

Another keyword is "Extracellular Vesicles" that happened to be neglected in the body. Our cells and also bacteria secrete them, filled with a plethora of molecules of many many classes, which alter the body's response to stimuli.

Basically, what microorganisms have been doing to plants/other organisms, but now we know how and that it is happening similarly in us, too.