TdT (Terminal deoxynucleotidyl transferase) is a DNA polymerase with a molecular weight of 58kD distributed in the nucleus. TdT is expressed in primitive T and B lymphocytes in normal thymus and bone marrow. During the maturation of the immune system, it can identify TdT-positive cell populations in primary and secondary lymphoid organs. It shows high enzyme activity in the leukocytes of some leukemia patients, which is of great significance.
Staining Tissue
As Figure shows:
Thymoma tissue stained with TDT