Phagocytosis of tumor cells by human monocytes cultured in recombinant macrophage colony-stimulating factor

David H. Munn, Nai Kong V. Cheung

Research output: Contribution to journalArticle

109 Scopus citations

Abstract

Macrophages and cultured human monocytes can mediate efficient antibody-dependent cytotoxicity (ADCC) against human tumor cells using monoclonal antibodies (mAbs). The mechanism of this killing is usually assumed to involve secreted factors (reactive oxygen intermediates, tumor necrosis factor, or other cytotoxic factors) leading to target cell lysis. In this study, we present evidence that phagocytosis ofintact target cells is the principal mechanism of antitumor cytotoxicity in our in vitro model of ADCCby cultured monocytes. Human monocytes cultured in recombinant human macrophage colony-stimulating factor ingested up to 100% of fluorochrome-labeled melanoma and neuroblastoma target cells, in the presence of an appropriate antitumor mAb. Electron microscopy demonstrated phagocytosis ofintact tumor cells by cultured monocytes during ADCC. All of the radionuclide in radiolabeled target cells was taken up by monocytes during phagocytosis. By preventing the release of radioisotope tracers, phagocytosis thus prevents the detection of this very efficient form of cytotoxicity by most conventional assays.

Original languageEnglish (US)
Pages (from-to)231-237
Number of pages7
JournalJournal of Experimental Medicine
Volume172
Issue number1
DOIs
StatePublished - Jul 1 1990

ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology

Fingerprint Dive into the research topics of 'Phagocytosis of tumor cells by human monocytes cultured in recombinant macrophage colony-stimulating factor'. Together they form a unique fingerprint.

  • Cite this