Antibody-induced release of cellular proteinases: loss of adhesion of human melanoma cells after binding of anti-melanoma antibody.

Journal Article (Journal Article)

Incubation of monolayer cultures of human melanoma cells with monkey anti-human melanoma IgG resulted in loss of cellular adhesion. Release of melanoma cells from the culture dish was not the result of cytotoxicity. Antibody-induced cell detachment was partially inhibited by the addition of diisopropylfluorophosphate (DFP), and detachment was completely inhibited by the addition of lima bean trypsin inhibitor. Thiol and carboxyl proteinase inhibitors did not block antibody-induced cellular detachment. An IgG dose-dependent increase in DFP-inhibitable caseinolytic activity was demonstrated in the culture medium of melanoma cells incubated with anti-melanoma IgG, but not in those incubated with normal monkey IgG. Medium collected from antibody-treated cell cultures and incubated with protein A-Sepharose to remove IgG caused detachment of melanoma cells in fresh cultures. Preincubation of this conditioned medium from antibody-treated cell cultures with DFP abolished the medium's ability to mediate loss of cellular adhesion. These data suggest that incubation of melanoma cells with immune IgG results in release of a serine proteinase that mediates cellular detachment.

Full Text

Duke Authors

Cited Authors

  • Singer, KH; Hashimoto, K; Stuhlmiller, GM; Lazarus, GS

Published Date

  • March 1982

Published In

Volume / Issue

  • 128 / 3

Start / End Page

  • 1321 - 1326

PubMed ID

  • 7035565

International Standard Serial Number (ISSN)

  • 0022-1767


  • eng

Conference Location

  • United States