Early expression of triggering receptors and regulatory role of 2B4 in human natural killer cell precursors undergoing in vitro differentiation

Simona Sivori, Michela Falco, Emanuela Marcenaro, Silvia Parolini, Roberto Biassoni, Cristina Bottino, Lorenzo Moretta, Alessandro Moretta

Research output: Contribution to journalArticle


In this study we analyzed the progression of cell surface receptor expression during the in vitro-induced human natural killer (NK) cell maturation from CD34+ Lin- cell precursors. NKp46 and NKp30, two major triggering receptors that play a central role in natural cytotoxicity, were expressed before the HLA class I-specific inhibitory receptors. Moreover, their appearance at the cell surface correlated with the acquisition of cytolytic activity by developing NK cells. Although the early expression of triggering receptors may provide activating signals required for inducing further cell differentiation, it may also affect the self-tolerance of developing NK cells. Our data show that a fail-safe mechanism preventing killing of normal autologous cells may be provided by the 2B4 surface molecule, which, at early stages of NK cell differentiation, functions as an inhibitory rather than as an activating receptor.

Original languageEnglish
Pages (from-to)4526-4531
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Issue number7
Publication statusPublished - Apr 2 2002


ASJC Scopus subject areas

  • General
  • Genetics

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