Growth inhibition of mammalian cells by eosinophil cationic protein

Takashi Maeda, Midori Kitazoe, Hiroko Tada, Rafael De Llorens, David S. Salomon, Masakazu Ueda, Hidenori Yamada, Masaharu Seno

Research output: Contribution to journalArticlepeer-review

56 Citations (Scopus)


Eosinophil cationic protein (ECP), one of the major components of basic granules of eosinophils, is cytotoxic to tracheal epithelium. However, the extent of this effect on other cell types has not been evaluated in vitro. In this study, we evaluated the effect of ECP on 13 mammalian cell lines. ECP inhibited the growth of several cell lines including those derived from carcinoma and leukemia in dose-dependent manner. The IC50 values on A431 cells, MDA-MB-453 cells, HL-60 cells and K562 cells were estimated to be ≈1-5 μM. ECP significantly suppressed the size of colonies of A431 cells, and decreased K562 cells in G1/G0 phase. However, there was little evidence that ECP killed cells in either cell line. These effects of ECP were not enhanced by extending its N-terminus. Rhodamine B isothiocyanate-labeled ECP started to bind to A431 cells after 0.5 h and accumulated for up to 24 h, indicating that specific affinity for the cell surface may be important. The affinity of ECP for heparin was assessed and found to be reduced when tryptophan residues, one of which is located at a position in the catalytic subsite of ribonuclease in ECP, were modified. The growth-inhibitory effect was also attenuated by this modification. These results suggest that growth inhibition by ECP is dependent on cell type and is cytostatic.

Original languageEnglish
Pages (from-to)307-316
Number of pages10
JournalEuropean Journal of Biochemistry
Issue number1
Publication statusPublished - 2002


  • Cell cycle
  • Colony formation
  • Cytostatic effect
  • Eosinophil cationic protein (ECP)
  • Growth inhibition

ASJC Scopus subject areas

  • Biochemistry


Dive into the research topics of 'Growth inhibition of mammalian cells by eosinophil cationic protein'. Together they form a unique fingerprint.

Cite this