Figure 2. Epidermal MrgprD-expressing nerve endings are reduced by long-term LC ablation.

(A) Representative immunofluorescent microscopic image of an epidermal whole-mount from WT and LC^DTA mice ears stained for MHC-II to identify LC (green) and PGP 9.5 to identify neuron (red). (B) Quantification of intra-epidermal nerve fiber number (IENF) from transverse skin sections stained with PGP 9.5 from LC^DTA and littermate (WT) controls. (C) As in B except IENF were quantified from LC^DTR mice treated with PBS (−) or with DT for 3 days or 30 days. (D, E) Quantitative analysis of IENF from transverse section stained with GFRα2 (D) or GFRα3 (E) from WT and LC^DTA mice. (F) Representative confocal image of Mrgprd^TdT skin whole mount to identify MC (green) and MrgprD-expressing neurons (red). (G) Representative epidermal whole-mounts from the ears of Mrgprd^TdT and Mrgprd^TdTxLC^DTA mice stained for MHC-II to identify LC (green) are shown. (H) Quantification of IENF of MrgprD+ nerve from transverse skin sections from Mrgprd^TdT and Mrgprd^TdT x LC^DTA mice. (I) Ear thickness at 6 hours following application of 1% croton oil in Mrgprd^DTR or Mrgpra3^DTR mice treated with control PBS or DT is shown. (J) Mrgprb2 mRNA expression in FACSorted dermal mast cells isolated from naive PBS or DT treated Mrgprd^DTR mice is shown. (K) Quantification of Evans blue dye 20 mins after challenged with vehicle or compound 48/80 in WT mice or DT treated Mrgpra3^DTR, Mrgprd^DTR mice. Each symbol represents data from an individual animal. Results are represented as mean ± SEM from 2-3 individual experiments with cohorts of n=3-4. Significance was calculated using unpaired Student’s t test (B, D, E, H, I, J) and one-way ANOVA (C, K). **p < 0.01, ***p < 0.001; n.s, no significant difference. Scale bars represent 20 μm in A, G; and 50 μm in F.