The level of CD47 expression by apoptotic cells is dependent on the mode of apoptosis induction.

<p>Apoptosis was induced by various methods as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0075595#s2" target="_blank">Materials and Methods</a> and CD47 surface expression was measured by flow cytometry. (A) MCF-7 cells were treated with staurosporine for 1.5 h and then washed and incubated for the indicated times. Time-dependent reduction in CD47 expression is shown. (B) CD47 expression in fibroblasts (upper panels) and HEK293 cells (lower panel) 24 h after induction of apoptosis with either staurosporine (left panels) or anti-FAS (right panel). (C) CD47 surface expression on MCF-7 cells (left panel), fibroblasts (middle panel) or HEK293 cells (right panel) 24 h after apoptosis induction with H₂O₂ (upper panels) or γ-irradiation (lower panels). Filled grey area: isotype control; Thick black line: untreated cells; Grey line: treated cells. Similar results were obtained in at least three experiments. (D) MFI results of three separate experiments as in A-C were normalized and are presented as relative to the level of CD47 expression by live untreated cells. White bar: γ-irradiation-treated cells; Black bar: H₂O₂-treated cells; Light grey bar: staurosporine-treated cells; Dark grey bar: anti-FAS-treated cells. Left panel: MCF-7 cells; Right panel: fibroblasts.