I'm fairly out of my depth with this stuff, so this is an honest inquiry: how do the magnetic nanoparticles fit into the equation?
I realize that, once coated with a suitably tailored binding protein, the particles will collect whatever target the binding protein was specified for (presumably this could even be tailored, for any target where a suitably tame binding compound is available), and probably fairly efficiently because of the absurd surface area of nanoparticles.
What I don't understand is the necessity of using the nanoparticles. It was my understanding that, outside of seriously immunocompromised victims, T-cells(and possibly other flavors of phagocytes, I'm fuzzy on the details) are extremely adept at engulfing and destroying foreign bodies, including 'clumps' produced by targets bound to the antigens produced by B-cells. This technique appears to be using a synthetic/introduced antigen(which makes sense if the immune system isn't producing the necessary antigen, or not ramping up production fast enough); but it also introduces the nanoparticles so that the antigen clumps can be magnetically scrubbed from the bloodstream, rather than cleaned up by the T Cells.
What is the peculiarity here that would make introducing the novel clump-scrubbing mechanism necessary and worthwhile?