For 10 points, name this structure that serves to filter foreign antigens and release namesake infection-fighting cells into the blood, located prominently in the groin, neck, and armpits.
For the most part, each one has a hilus into which blood vessels can enter or exit. A framework of trabeculae emanate from the capsule and the germinal centers, where macrophages and inactivated B and T cells reside. For 10 points, name this structure that serves to filter foreign antigens and release namesake infection-fighting cells into the blood, located prominently in the groin, neck, and armpits.
For the most part, each one has a hilus into which blood vessels can enter or exit.
{lymph node}s