Is It the Chicken or the Egg?

The expression of the cure on the cty eight cert cells actually goes down as severity increases. How can you have these cercetet cells, but yet they're able to eliminate cells if they are expressing an inhibitory receptor? The argument is that if they have very high levels of inhibitory receptor, they are a not killing a lot of things. But if they down regulate it, now they don't have as much inhibition and they can kill.