T cells
A)bind with free extracellular antigen
B)bind with MHC molecules only when they are in association with a foreign antigen
C)are responsible for cell-mediated immunity
D)have characteristics a and c
E)have characteristics b and c

Question

Quizplus · Accepted Answer

T cells bind only with MHC molecules presented by antigen-presenting cells (APCs) and it must be in association with a foreign antigen. This is called the antigen-specificity of T cells. T cells are responsible for cell-mediated immunity, which include killing of infected cells, activation of other immune cells, and production of cytokines. Therefore, the correct answer is E, which means T cells have characteristics b and c.

T Cells