I'm not sure which forum this fits in. Many ME/CFS researchers have noted a shift toward T2-cell in the immune response in ME/CFS patients. I don't remember (brain fog) reading any theories about what causes this shift. Has anyone come across any theories? I'm also wondering how that would relate to the theory that ME/CFS is an autoimmune disease. It's interesting that women tend to shift to T2 dominance in the 2 weeks preceeding their period. I wonder if that could have anything to do with more women than men having ME/CFS. Women get kind of a double T2 whammy.