So we have an inactivated helper T cell, a type of Lymphocyte, T Lymphocyte that can now go on and bind to this MHC class two complex that contains that antigen. So we have the binding process takes place and when they bind and form this entire complex, the macrophage begins to release a special chemical known as interleukin one. And the interleukin one essentially goes on to and interacts with this inactivated helper T cell. And what that does is it activates that helper T cell. Now, once it's activated, it basically releases from this macrophage and it moves on and it finds a B Lymphocyte. Now, remember, B Lymphocytes are part of our adaptive immune system, just like these helper T cells are.