The ninth component of complement and the pore-forming protein (perforin 1) from cytotoxic T cells: Structural, immunological, and functional similarities

John Ding E. Young, Zanvil A. Cohn, Eckhard R. Podack

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The ninth component of complement (C9) and the pore-forming protein (PFP or perforin) from cytotoxic T lymphocytes polymerize to tubular lesions having an internal diameter of 100 Å and 160 Å, respectively, when bound to lipid bilayers. Polymerized C9, assembled by slow spontaneous or rapid Zn2+-induced polymerization, and polyperforin, which is assembled only in the presence of Ca2+, constitute large aqueous pores that are stable, nonselective for solutes, and insensitive to changes of membrane potential. Monospecific polyclonal antibodies to purified C9 and PFP show cross-reactivity, suggesting structural homology between the two molecules. The structural and functional homologies between these two killer molecules imply an active role for pore formation during cell lysis.

Original languageEnglish (US)
Pages (from-to)184-190
Number of pages7
Issue number4760
StatePublished - Jan 1 1986


ASJC Scopus subject areas

  • General

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