2D transwell chemotaxis and transendothelial migration are impaired in SIRPα^Δcyt phagocytes.

<p>A) C5a-induced 2D migration in transwell chemotaxis assay is regulated by SIRPα signaling. Data shown represents the difference between the maximum and the minimum fluorescent value reached within 1 h in BMDN and 2 h in BMDM. Values shown represent averages ± SEM of n = 4 independent experiments. Asterisk, p≤0,05. B) Transendothelial migration is deficient in SIRPα^<b>Δcyt</b> BMDN. WT and SIRPα^<b>Δcyt</b> BMDN were seeded over a mrTNFα-stimulated monolayer of bEnd5 cells. After 5’ a flow ratio of 0.9dyn/cm^<b>2</b> was applied and transendothelial migration was monitored by time lapse video microscopy using a phase-contrast lens. Data shown represent means ± SEM of 12 measurements done in 3 independent experiments. Asterisk, p≤0,05. C) BMDN and BMDM from SIRPα^<b>Δcyt</b> mice have similar levels of integrin expression. Cells were cultured as described in material and methods and stained with specific Abs against the indicated integrins. Gating was based on FCS and SSC. Histograms from representative experiments are shown for BMDN and BMDM. The dotted line represents the isotype control wile the continuous line represents WT (gray filled) or SIRPα^<b>Δcyt</b> (no filling) stainings.