CD8A and alopecia areata: Myasthenia gravis and alopecia areata represent primary pathogenic pathways involving two distinct adaptive immune system arms; myasthenia gravis is B cell-mediated, while alopecia areata is characterized by damage of the hair follicle due to infiltration of the cytotoxic subset of CD8+ and NKG2D+ T cells into hair follicles [12–14].