1. 1967: Thymidine Kinase 1 (TK1) was acknowledged as a Cell Proliferation Marker.
2. 1985: TK1 research team was established at Karolinska Institute. SSTK’s present Chief Scientist, Professor Ellen He, was selected as one of the members of the TK1 research team.
3. 1990s: STK1 specificity was established. The first TK1 monoclonal & polyclonal antibody was successfully developed.
4. 2002: The TK1 research team discovered and developed chicken anti-TK1-IgY antibody. Research on TK1 started to turn into clinical research. In the same year, SSTK was founded in Shenzhen city, China.
5. 2004: The TK1 research team announced the 3-D spatial structure of TK1 enzyme.
6. 2006: The Thymidine Kinase 1 Cell Cycle Assay Kit and The High Sensitive Enhanced Chemiluminescent (ECL) Dot Blot Assay were successfully produced by SSTK and have since then been applied in the market.
7. 2007: The clinical application value of TK1 was discussed and acknowledged at the 35th Meeting of the International Society for Oncodevelopmental Biology and Medicine, ISOBM 2007, and was recommended for the monitoring and long-term follow-up in the blood system and solid tumors.
8. 2012: Sino-Swed TK1 Risk Assessment Platform established. By the end of this year, over 1,000,000 individuals accepted STK1 detection in health screening. A 10-institution-united research during 2005-2011 covered 35,365 subjects showed a result in which the statistical analysis ROC-value is 0.96. This research greatly verified that the SSTK patented TK1 technique is useful for health screening and clinical evaluation.
9. 2013: TK1 Assay (SSTK exclusive licenced) was indexed into “The 2013 Directory for Clinical Test Items in Medical Institutions” （by China Ministry of Health); More than 300 professional medical institutions in Swede, Canada and China have been introducing TK1 test technique; TK1 test has been included into medical insurance and into civil servants’ health screening items.
10. 2014: SSTK company moved into the new 2300m2 office in Shenzhen. It is a functional headquarter integrates Research&Development (R&D), Marketing, Production and Quality Control (QC) as a whole. Meanwhile, Prof. Sven Skog and Prof. Ellen He, working as the SAFEA (State Administration of Foreign Experts Affairs) in China, were met by Xi Jinpin, the Chinese President and Li KeQiang, the Preminister of China. For a greater vision, China Health Promotion Foundation launched a Multi-Health-Management-Center Research Project of TK1 in early tumor risk assessment for whole China.
11.2016: SSTK published the world's largest sample of early cancer risk screening research results.
12.2017: The monograph of the world's first study of thymidine kinase 1 (TK1) "Prevention and early detection of human tumor" was published in Europe.