TCR Vβ1 is a variant of the TCR Vβ chain that is expressed by a subset of αβ+ T cells. Aberrant expression of TCR Vβ chains has been associated with infection and cancer. TCR Vβ1 is reported to be preferably used by autoreactive T cells in a model of autoimmune thyroiditis and diabetes. Skewing of TCR Vβ repertoire to Vβ1 and Vβ9 has also been reported in patients with multiple sclerosis, reactive arthritis, and Kawasaki disease.