This question is testing your knowledge on T- and B-cell activation.
My specifically it is asking about B-cell activation and class switching. The following steps occur during this process, and step 4 is what you need to know in order to answer this question correctly:
1) Th-cell activation as above.
2) B-cell receptor–mediated endocytosis.
3) Exogenous antigen is presented on MHC II and recognized by TCR on Th cell.
4) CD40 receptor on B cell binds CD40 ligand (CD40L) on Th cell.
5) Th cells secrete cytokines that determine Ig class switching of B cells.
6) B cells are activated and produce IgM.
They undergo class switching and affinity maturation.
submitted by ∗surgerydoctorca_sgu(6)
This question is testing your knowledge on T- and B-cell activation.
My specifically it is asking about B-cell activation and class switching. The following steps occur during this process, and step 4 is what you need to know in order to answer this question correctly:
1) Th-cell activation as above. 2) B-cell receptor–mediated endocytosis. 3) Exogenous antigen is presented on MHC II and recognized by TCR on Th cell. 4) CD40 receptor on B cell binds CD40 ligand (CD40L) on Th cell. 5) Th cells secrete cytokines that determine Ig class switching of B cells. 6) B cells are activated and produce IgM. They undergo class switching and affinity maturation.