anti-Terminal deoxynucleotidyl transferase (human), Rabbit Monoclonal (RM379)

Terminal Deoxynucleotidyl Transferase (TdT) is a DNA polymerase located in the cell nucleus which catalyzes the polymerization of deoxynucleotides at the 3' hydroxyl ends of oligo or polydeoxynucleotide initiators and functions without a template. TdT adds N-nucleotides to the V, D, and J exons of the TCR and BCR genes during antibody gene recombination, enabling the phenomenon of junctional diversity. The diversity introduced by TdT has played an important role in the evolution of the vertebrate immune system, significantly increasing the variety of antigen receptors that a cell is equipped with to fight pathogens. TdT is expressed in immature, pre-B, pre-T lymphoid cells and acute lymphoblastic leukemia/lymphoma cells. TdT is considered to be a highly specific marker for the diagnosis and classification of acute lymphoblastic lymphoma/leuksemias. The determination of TdT expression is most valuable when it is difficult to differentiate histologically between lymphoblastic lymphoma and Burkitt's lymphoma.