FIELD: immunobiotechnology. SUBSTANCE: purified immunoglobulin polypeptide is obtained using purified or partially purified extracellular domain of human receptor PDGF of β-type. Polypeptide binds specifically with growth factor receptor releasing from cells that express receptor of human β-PDGF-R but it does not bind specifically with human α-PDGF-R. Polypeptide is monoclonal antibody and can be bound with definite label. Fragment of the above-mentioned polypeptide exhibits amino acid sequence that is similar with sequence of region determining its complementarity. Polypeptide or its fragment is a component of composition used for diagnosis and treatment of disorders of cellular proliferation caused by PDGF. Polypeptide or its fragment is prepared in the process of culturing cellular strain expressing hybridoma ATCC HB 109038 mainly. EFFECT: improved method of polypeptide preparing, valuable medicinal properties. 12 cl, 11 dwg
