B lymphocytes, also known as B cells, are the only cells to produce antibodies, which the immune system needs to fight off foreign intruders like pathogens in order to protect the human body. On their surface, B cells carry B cell receptors which activate the B cells when an antigen, a substance on the surface of a pathogenic germ, binds to them.  B cells remain … Continue reading Researchers identify previously unknown protein in immune cells.