Dendritic cell and lymphocyte, coloured scanning electron micrograph (SEM). Interaction between a dendritic cell (blue) and a T lymphocyte (yellow), two components of the body's immune system. Both are types of white blood cell. T lymphocytes recognise a specific site on the surface of pathogens or foreign objects (antigens), bind to it, and produce antibodies or cells to eliminate that antigen. Dendritic cells are antigen- presenting cells (APCs), they present antigens to T lymphocytes, which can only recognise antigens when they are presented by APCs. Magnification: x2350 when printed 10cm wide.
