HLA-E and myalgic encephalomeyelitis/chronic fatigue syndrome: Differential regulation of HLA-B (Class I) and HLA-E (Non-classical Class I) were common to LC and ME/CFS, but HLA-DRB1 (Class II) was differentially regulated in the LC data alone, and HLA-A (Class I), HLA-DQB1 and HLA-DPB1 (both class II) were also differentially regulated in the ME/CFS study.