Mechanisms of FLBs translocation. a) Compared to the i.m. route, direct injection of FLBs in the tail vein of C57 mice was associated with almost no brain translocation at both d21 and d90 post-injection; b) Popliteal and inguinal DLN ablation was associated with a marked decrease of FLB-loaded cells in blood, spleen and brain at d21 post-injection; c) The mdx mouse with altered BBB showed a marked increase of the perivascular CD11b+ cell population, and significant angiogenesis assessed by an increase of CD31+ endothelial cells, compared to normal C57 mice; d-e)Mdx mice showed increased incorporation of FLBs in brain; compared to C57 mice, mdx mice had increased FLB neurodelivery at both d21 and d90, as assessed by both histology (d) or after CD11b+ cell sorting (e); f) At d21, FLBs were mainly detected outside capillary basement membranes immunostained for collagenIV (upper panel), closely associated with CD11b+ perivascular macrophages (lower panel); (histograms: n = 3 per group, mean + SD, * P <0.05, ** P <0.01, *** P <0.005; bar in d: 10 μm). d, day; DLN, draining lymph nodes; FLB, fluorescent latex beads; n, number.
Khan et al. BMC Medicine 2013 11:99 doi:10.1186/1741-7015-11-99