A polypeptide containing epitope of the amino acid sequence shown in SEQ ID NO:3 is provided, which is selected from the amino acid sequence of SEQ ID NO:3 and amino acids at 16-32 positions, amino acids at 1-30 positions, amino acids at 50-80 positions and amino acids at 17-200 positions of the amino acid sequence shown in SEQ ID NO:3. The nucleic acid molecule encoding the polypeptide, recombinant vectors and host cells comprising the nucleic acid molecule are also provided. The polypeptide and the nucleic acid molecule encoding it can be used for preparing reagents, kits or devices for diagnosing the diseases characterized by EECP expression and pharmaceutical compositions for preventing or treating the diseases characterized by EECP expression by increasing or inhibiting EECP expression and/or activity.
