Question: How long do macrophages dock with helper T cells?

Sean Murphy answered on 15 Mar 2012:

When a macrophage has eaten an invader it travels to the nearest lymph node to present information about the captured pathogen. The macrophage displays an antigen fragment from the invader on its own surface, a process called antigen presentation. When the receptor of a helper T cell recognizes the antigen, the T cell is activated. This step can take anywhere between 8 hours and 48 hours. Once activated, helper T cells start to divide and to produce proteins that activate B and T cells as well as other immune cells.