A minority of HLA-DR1 molecules at the cell surface can bind superantigens Thibodeau, J.; Leveillee, C.; Cloutier, I.; Leroux, J.Y.; Mourad, W.; Sekaly, R.P. FASEB Journal 9(4): A1059 1995 https://eurekamag.com/research/029/678/029678305.php