Tumor liberated protein (TLP): its potential for diagnosis and therapy.

Our earlier studies led to the purification of a similar antigen from several types of human tumours which had the following properties: It provoked a delayed reaction in certain cancer patients which could be demonstrated both in vivo and in vitro (1). In contrast, healthy individuals did not react to this antigen. Subsequent studies led to a higher degree of purity of tumour antigen which enabled a partial sequence (2). The eight amino acid sequence obtained led to the synthesis of the corresponding peptide. This synthetic peptide was then used to raise specific antibodies in rabbits. The availability of such antibodies enabled to undertake a range of studies. Those investigations revealed that the antibodies were tumour specific because they reacted only with certain types of tumours but not with normal cells nor with other types of tumour tissues. We decided to name this tumour antigen as TLP for tumour liberated protein.