ABOVE: A lymph node with B cells labeled yellow and CD4+ T cells in blue.
FLICKR, NIAID
Just like any skilled workers, many antibody-producing cells require training to do their job proficiently. That education happens in germinal centers, structures in the lymph nodes that form upon infection or vaccination, then disappear after a few weeks. Although our bodies have some antibody-spewing plasmablasts at the ready when they first encounter a new virus, better, longer-lasting antibody-making cells emerge from these lymphoid boot camps.
In what’s described as the dark zone of the germinal center based on its appearance under a microscope, B cells swiftly multiply and diversify into clones that carry differently shaped antibodies. They then drift into the “light zone,” where they face examination by specialized T cells that test their ability to recognize viral protein. This test is tough; imperfect clones are sent back to the dark zone for refinement ...
