Antibodies can be used to localize particular antigens within histological sections. In this case, a frozen section of a mouse lymph node is stained with a fluorescent antibody specific for an antigen expressed by T-cells. This image demonstrates the fact that T-cells are located only within specific regions of lymphoid tissue, the Diffuse Cortex (DC) of the lymph node, in this case. Another region within the node, the Primary Follicle (PF) contains very few T-cells.