I'm as confused as you are: I thought the symbol for gamma was a kind of handwritten letter "Y", but that comes from my days hunting moths, (don't ask, it's a long story),* so I'm not sure what the, "g" means. If it is interferon gamma, then that has been known for a long time to significantly worsen MS.
I agree that that poor old mouse is long overdue for retirement, and it's a scandal that EAE is still the only model we have, but for the moment we're stuck with either cells in a Petri dish or a disabled rodent and I haven't heard of any better models on the horizon. We can only hope that, whatever the differences, useful pointers could be found.
As for the reference to, "inflammation", etc., I get fed up with reading that as well. Whenever I see it I hope that it's simply down to a journalist searching for a quick, 3-line description of MS and lifting it from a 20 year old self-help leaflet.
*Perhaps "hunting" sounds a bit grand… you only need a teensy weensy rifle and mounting the antennae on a wooden plaque above the fireplace is, to be frank, not that impressive,