Cell surface markers are proteins or glycoproteins found on the surface of cells that often serve as markers to identify specific types of cells.
Antigens: Substances that can induce an immune response and subsequently react with produced antibodies or T cells.
Molecules that consist of a carbohydrate plus a protein; they play essential roles in the body's immune system and its ability to fight off disease.
Protein molecules inside or on the surface of cells which receive chemical signals from outside the cell.