(1) II, take the antigen in and make a MHC-ANTIGEN COMPLEX,
(2) HELPER T, HELPER T, INTERLEUKIN-2
(1) B cells have MHC-___ self antigens. When a B cell is stimulated by the antigen it recognises, the first thing the B cell does it to ___.
(2) Then a ___ cell is required for costimulation. The ___ cell does this by secreting ___