Which of the following is not true regarding super-antigens-

Reference :Robbins basic pathology 9th edition pg 110:An additional group of secreted bacterial proteins called superantigens also cause a syndrome similar to septic shock (e.g., toxic shock syndrome). Superantigens are polyclonal T-lymphocyte activators that induce T cells to release high levels of cytokines, which in turn results in a variety of clinical manifestations, ranging from a diffuse rash to vaso- dilation, hypotension, and death.