Transmigration of neutrophils and expression of interleukin-1-beta (IL-1β). (A) Representative fluorescent micrographs of monoclonal anti-neutrophil antibody (NIMP) and IL-1β staining from the empty scaffold, multipotent stromal cell (MSC), and MSC/endothelial cell (MSC/EC) constructs, using mouse-specific antibodies after 3 weeks of implantation in vivo (10× magnification, scale bar = 100 μm). (B) The number of neutrophils was significantly higher in the MSC/EC group (***P <0.001, n = 6). The number of IL-1β-positive cells was lower in the MSC/EC group, but this was not a statistically significant difference. Five sections from each mouse and five images for each section were used for the image quantification. (C) Relative protein expression of IL-1β in MSC and MSC/EC constructs.