A woman had a high fever, hypotension, and a diffuse macular rash. When all cultures showed no bacterial growth, a diagnosis of toxic shock syndrome was made. Regarding the mechanism by which the toxin causes this disease, which one of the following is LEAST accurate?

  •  The toxin activates many CD4-positive T cells, and large amounts of interleukins are released.
  •  The toxin binds to both the class II MHC protein and the T-cell receptor.
  •  The toxin has an A-B subunit structure—the B subunit binds to a receptor, and the A subunit enters the cells and activates them.
  •  The toxin is not processed within the macrophage.