TSHR and thromboangiitis obliterans: The methods employed to establish an animal model of TAO include the use of pituitary extracts combined with thyroidectomy to treat the animal, thyrotropin receptor (TSHR) peptide or nucleic acid immunization, injection of TSHR-transfected cells or TSHR-activated T cells into experimental animals, and multi-gene co-immunization of animals [7–10].