Fig. 4.

CXCL12 stimulation increases active-β1-integrin. A: representative histogram showing CXCL12 stimulation (2.5 nM) (shaded region) for 1 h at 37° increased active-β1-integrin on the cell surface of Caco2-BBe cells compared with unstimulated cells (gray line). MnCl₂ (1 mM) (gray dashed line) synthetically produced maximal β1-integrin activation. B: quantification of active β1-integrin on Caco2-BBe cells that were untreated (no stim, open bars) stimulated with 2.5 nM CXCL12 (solid) or incubated with synthetic controls MnCl₂ (hatched bar) or EDTA (5 mM) (shaded bar). Data are expressed as the mean percentage of unstimulated mean fluorescence intensity ± SE of 5–6 experiments. Asterisk denotes statistically significant difference from untreated cells (*P ≤ 0.05, **P ≤ 0.01).