The two-signal activation process for T cells includes
A) interaction of the T-cell receptor with the MHC-antigen complex on the APC AND binding between co-stimulatory proteins on the T cell and APC surfaces.
B) the presence of a superantigen and the presence of appropriate antibodies.
C) interaction of the T-cell receptor with the MHC-antigen complex on the APC AND the presence of a superantigen.
D) the presence of antibodies AND binding between co-stimulatory proteins on the T cell and APC surfaces.
E) the presence of a superantigen AND binding between co-stimulatory proteins on the T cell and APC surfaces.
Answer: A
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