Figure 2.

CX3CR1-GFP^low inflammatory monocytes preferentially extravasate at laminin 511^low sites. (A) Representative confocal microscopy of whole mount cremaster muscle from a WT host carrying CX3CR1^GFP/+ bone marrow stained with anti-laminin α5 and anti-PECAM-1 antibodies (i); single channel images are shown in (ii, iii, iv); scale bar = 100 μm. Experiment was repeated three times with one animal with the same results. (B) To track CX3CR1-GFP^low inflammatory monocytes GFP mean fluorescence intensity (MFI) was measured in situ in areas of high and low laminin 511 expression (see Fig. S2A), revealing a higher proportion of CX3CR1-GFP^low cells, expressed as a percent of total GFP⁺ cells, at laminin 511^low compared to laminin 511^high sites; data are means ± SD of three mice from three separate experiments and at least five postcapillary venules in two different areas/mouse; different experiments are marked by different colors. (C) Quantification of GFP MFI and migration speed of individual CX3CR1^high and CX3CR1^low cells analyzed in three WT hosts from three separate experiments. (D) Average migration velocities of extravasating GFP⁺ cells at laminin 511 low and high sites in WT controls, and in Lama4^−/− and Tek-cre::Lama5^−/− chimeras. Data in (C, D) are means ± SD calculated from 39-64 cells analyzed in three mice per chimera (marked by different colors); movies were captured at 4 h post-administration of CCL2. Significance of data in (B–D) were calculated using Mann-Whitney tests since the data did not pass the normality test by D`Agostino & Pearson; the exact p-values are shown in the graph.