NCIt definition : A white blood cell that, after being in contact with an antigen, rearranges its DNA
to defend against that one specific type of antigen. After activation, it can then
proliferate and differentiate into memory cells, antibody-secreting cells or plasma
cells.;
Alternative definition : NCI-GLOSS: An immune cell such as a T or B lymphocyte that responds to a single, specific
antigen.;