A Cross-Reaction is an Interaction Between an Antibody or TCR

Question

A cross-reaction is an interaction between an antibody or TCR and
A) a heterologous antigen.
B) a homologous antigen.
C) either a heterologous or homologous antigen.
D) None of these are correct.

Accepted Answer

A cross-reaction occurs when an antibody or TCR recognizes and binds to an antigen that is structurally similar, but not identical, to its original target antigen, which is known as a heterologous antigen. Therefore, option A is the best choice, as it is the only one that correctly identifies the type of antigen involved in a cross-reaction.