Here's a paper that delves into "T cell migration into the central nervous system during health and disease: Different molecular keys allow access to different central nervous system compartments"
In my simple terms, it speaks to how the blood brain barrier can be stimulated/inflamed to allow T cells transit across the BBB to begin inflicting inflammation in the CNS.
There is so much more research needed to begin getting a better grasp on how inflammation affects our brains which in turn affects our entire being. And let's hope that leronlimab can play in important part resolving these conditions.