Fig. 5.

Keratinocytes do not compensate for the absence of Langerhans cells. (A,B) Representative widefield images of the scale epidermis in Tg(mpeg1:NTR-EYFP) adults after 3 days of mock treatment (A) or 7 mM MTZ treatment to ablate mpeg1⁺ cells (B). mpeg1⁺ cells: 255.1±133.17 and 73.8±23.28 (mean±s.d.) after 3 days of mock or MTZ treatment, respectively. (C) Quantification of debris engulfed by keratinocytes after 3 days of exposure to MTZ in animals with or without Tg(mpeg1:NTR-EYFP) (denoted as +MTZ mpeg1 ablation or +MTZ control, respectively). Two-way ANOVA followed by Bonferroni tests determined significance of differences between (+MTZ−NTR) and (+MTZ+NTR) conditions. *P<0.05. n=4-10 ROIs for +MTZ−NTR (from three fish, six scales) and n=15-16 ROIs for +MTZ+NTR (from seven fish, 13 scales). (D,E) Representative confocal images of mpeg1⁺ cells in the scale epidermis from adults of the indicated genotypes. Note the lack of mpeg1⁺ cells with the dendritic morphology of Langerhans cells in the csf1ra^mh5/mh5; csf1rb^mh108/mh108 mutant epidermis. Yellow dotted line boxes denote the regions magnified in insets. (F) Quantification of debris engulfed by keratinocytes in adults of the indicated genotypes. n=6-11 ROIs for csf1ra^mh5/+; csf1rb^mh108/+ (from three fish, four scales) and n=10 ROIs for csf1ra^mh5/mh5; csf1rb^mh108/mh108 (from three fish, five scales). Scale bars: 20 μm (A,B,D,E), 10 μm (D,E, insets). Error bars in C and F represent s.d.