The secondary signal needed from a T cell for a B cell to differentiate into a plasma cell is the crosslink between: A) CD8 (on the T_C cell) with MHC I (on the B cell) B) CD4 (on the T_H cell) with CD40 (on the B cell) C) MHC II (on the T_C cell) with CD4 (on the B cell) D) CD8 (on the T_C cell) with CD40 (on the B cell) E) CD154 (on the T_H cell) with CD40 (on the B cell)

Question

Quizplus · Accepted Answer

The secondary signal required for B cell differentiation into plasma cells is the interaction between CD154 on the T cell and CD40 on the B cell. CD154 (also known as CD40 ligand) is expressed on activated T cells and binds to CD40, which is expressed on B cells. This interaction triggers a cascade of downstream signaling events that leads to B cell differentiation into plasma cells. Therefore, choice E is the correct answer.

The Secondary Signal Needed from a T Cell for a B