Thymidinkinas 1 som tumörmarkör vid juvertumörer hos tik

Sammanfattning: Determination of serum thymidine kinase 1 (TK-1) activity is used as a tumour marker in both human and veterinary medicine. TK-1 is an intracellular enzyme involved in a salvage pathway of DNA synthesis. The expression of TK-1 is cell cycle dependent and the activity increases markedly after the G1 to S transition in the cell cycle and then declines rapidly in G2. The pronounced proliferative activity in tumour cells result in a higher TK-1 enzyme activity within the cell. The fact that the increased TK-1 activity can be measured in serum makes TK-1 a useful marker in diagnostics of neoplastic diseases and it provides information regarding prognosis and treatment effectiveness. In human medicine a radioactive based test is used to determine the TK-1 serum activity. A study has proved that the test also can be used to determine the TK-1 serum activity in dogs. The test is, however, limited in a more general use in veterinary practice since it is expensive and requires handling of radioactivity. Recently in human medicine antibodies has been used to measure the serum concentration of TK-1 in patients with solid types of tumours, e.g. breast cancer. This type of measurements has been successful and would be interesting to evaluate in veterinary medicine. In this study we have expressed two recombinant types of dog TK-1, dTK1DC12 and dTK1DC38. The two types have been used to evaluate specific dog TK-1 antibodies and have been showed to work as respectively positive and negative controls for the antibodies. In subsequent studies the recombinants can be used to increase the antibodies specificity. The recombinants are also important and central in a future development of a method in witch is possible to detect and measure dog TK-1 in tissue and serum by using specific antibodies.