Tissue Microarray (TMA) Construction

Tissue microarrays (TMAs) are constructed by removing a core — tube-shaped section — of tissue from a paraffin block (donor block) using a hollow needle and transferring this core to a predetermined position on a paraffin recipient block. TMAs are often used to compare control and diseased sections within one slide constructed on a semi-automated platform. Individual arrays can be constructed with as many as 360 cores of 0.6-millimeter diameter or 187 cores of 1-millimeter diameter. Additionally, tissue microarrays with up to 60 cores of 2-millimeter diameter can be manually created.