PRODUCTION AND CHARACTERISTICS OF ANTIBODIES AGAINST K1-3 FRAGMENT OF HUMAN PLASMINOGEN

Components of plasminogen/plasmin system play crucial role in fibrinolytic rocesses. They are also involved in regulation of cell activity in normalcy and various pathological conditions. In particular, kringle-containing proteolityc plasminogen fragments, which are denoted as angiostatins, participate in processes during neovascularization, metastasis, tumor growth, inflammation. Angiostatins are considered to be potential markers of diseases associated with vascular pathologies. Therefore, elaboration of specific and sensitive methods for their detection is still important area of inquiry. In the present study, approaches for obtaining of plasminogen fragments through its limited proteolysis by pancreatic elastase and further purification of proteolytic derivates by means of gel filtration and affinity chromatography on Lys-Sepharose are described. Polyclonal antibodies raised to fragment K1-3 have been produced, and their principal immunochemical properties have been studied. It has been found that antibodies purified on immunoaffine sorbent demonstrate different affinity toward plasminogen and its fragment, as follows: Glu-Pg > Lys-Pg > К1-3 > mini-Pg > К4. Based on the data obtained, immunological features of plasminogen kringle domains are discussed. Antibodies against fragment K1-3 could be applied in immunochemical analysis, in particular, Western blot, for detection of angiostatins as markers of tumor growth, metastasis, cardiovascular diseases and inflammation processes, and used as molecular tool for investigation of plasminogen/plasmin system functioning in health and disease.