1. TWEAK/Fn14 Signals Mediate Burn Wound Repair
Jing Liu, Yale Liu, Lingling Peng, Juxue Li, Kunyi Wu, Linlin Xia, Jiawen Wu, Sijia Wang, Xuening Wang, Qilu Liu, Weihui Zeng, Yumin Xia 
Journal of Investigative Dermatology 
Volume 139, Issue 1, Pages (January 2019)
DOI: /j.jid
Copyright © 2018 The Authors Terms and Conditions

2. Figure 1
Fn14 deficiency delays healing of burn wounds in BALB/c mice. (a) Skin wounds were monitored on days 0 (immediately after burning), 3, 7, 14, and 21. (b) Fewer wound areas were found in the WT mice on days 7 and 14. (c) The images of hematoxylin and eosin-stained sections are shown. Red arrows indicate renascent epidermis. (d) The epidermal thickness was measured, and thinner epidermis was observed in the KO mice on days 3, 7, and 14. (e) The TWEAK and Fn14 expression, Ki-67–positive cells, and apoptotic cells (red arrows) were detected through immunohistochemistry or TUNEL method on day 7. (f, g) The (f) Ki-67–positive cells and (g) apoptotic cells were counted, and significant differences were found between the two strains. Number of mice = 5. Representative images are shown. Scale bars = 25 μm. ∗P < 0.05, ∗∗P < 0.01, and ∗∗∗P < 0.001, comparison between WT and KO mice at the same time point. KO, knockout; WT, wild type.
Journal of Investigative Dermatology  , DOI: ( /j.jid )
Copyright © 2018 The Authors Terms and Conditions

3. Figure 2
Fn14 deficiency reduces inflammatory responses in burn wounds. (a) Iba-1–positive, CD3-positive, B220-positive, and Ly-6G–positive cells were detected by immunohistochemistry on day 7. Scale bars = 25 μm. (b) Inflammatory infiltration was scored semiquantitatively based on the staining of the four cell types. The mRNA expression levels of inflammatory cytokines, including (c) RANTES, (d) MCP-1, and (e) IP-10 were determined in the lesional tissue. (f–h) The proteins of RANTES, MCP-1, and IP-10 were determined by Western blotting. Number of mice = 5. Representative images are shown. ∗P < 0.05, compared with the mice of the same strain on day 0; ΔP < 0.05, compared with the WT mice at the same time points. KO, knockout; WT, wild type.
Journal of Investigative Dermatology  , DOI: ( /j.jid )
Copyright © 2018 The Authors Terms and Conditions

4. Figure 3
Fn14 deficiency inhibits the production of growth factors and relevant mediators in burn wounds. The mRNA expression levels of (a) TGF-β1, (b) EGF, (c) EGFR, (d) MMP-2, and (e) MMP-9 were determined in lesional tissue. (f, g) The proteins of TGF-β1, EGF, EGFR, MMP-2, and MMP-9 were determined by Western blotting. The β-actin band was the same as that in Figure 2f. (h) The expressions of EGFR, MMP-2 (green), and MMP-9 (red) were detected by immunohistochemistry or immunofluorescence on day 7. Scale bars = 25 μm. Number of mice = 5. Representative images are shown. ∗P < 0.05, compared with the mice of the same strain on day 0; ΔP < 0.05, compared with the WT mice at the same time points. KO, knockout; WT, wild type.
Journal of Investigative Dermatology  , DOI: ( /j.jid )
Copyright © 2018 The Authors Terms and Conditions

5. Figure 4
Fn14 deficiency suppresses extracellular matrix synthesis in burn wounds. (a) The distribution of cutaneous collagen (greenish blue) was evaluated by Masson’s trichrome staining. (b) The collagen fraction was measured, in which less collagen was observed in the KO mice on days 7 and 14. (c) The expression of α-SMA was detected by immunohistochemistry on day 7. (d–g) The mRNA expression levels of extracellular matrix components were determined by qRT-PCR. (h, i) The expression of these matrix proteins was determined by Western blotting. ∗P < 0.05, compared with the mice of the same strain on day 0; ΔP < 0.05, compared with the WT mice at the same time points. Scale bars = 25 μm. Number of mice = 5. Representative images are shown. α-SMA, α-smooth muscle actin; D, day; KO, knockout; WT, wild type.
Journal of Investigative Dermatology  , DOI: ( /j.jid )
Copyright © 2018 The Authors Terms and Conditions

6. Figure 5
TWEAK/Fn14 interaction enhances the migration of human DMECs and dermal fibroblasts. (a) Migration assays were performed from 0 to 48 hours after TWEAK stimulation (250 ng/ml). (b) The cells were stimulated with TWEAK (0–250 ng/ml) for 48 hours and were then subjected to migration assays. (c) The cells were pre-transfected with control or Fn14 siRNA, stimulated with TWEAK (250 ng/ml, 48 hours), and then subjected to migration assays. ∗P < 0.05, compared with blank group; ΔP < 0.05, compared with TWEAK alone group; #P < 0.05, compared with TWEAK + control siRNA group. (d, e) The representative images of migration assays for (d) DMECs and (e) dermal fibroblasts, respectively. Results are representative of three experiments. DMEC, dermal microvascular endothelial cell; siRNA, small interfering RNA.
Journal of Investigative Dermatology  , DOI: ( /j.jid )
Copyright © 2018 The Authors Terms and Conditions

7. Figure 6
TWEAK/Fn14 interaction promotes cytokine production of human DMECs and dermal fibroblasts. Cells were cultured in vitro and received TWEAK stimulation (250 ng/ml, 48 hours). (a, b) The mRNA expression levels of TGF-β1, EGF, EGFR, MMP-2, and MMP-9 in (a) DMECs, and (b) dermal fibroblasts were measured. (c) The concentrations of TGF-β1 and EGF in culture supernatants were determined through ELISA. (d) By immunofluorescence, the EGFR expression was determined in cells pre-transfected with siRNA. Scale bars = 5 μm. (e) The EGFR expression was evaluated by flow cytometry. (f, g) The proteins of EGFR, MMP-2, and MMP-9 were detected in DMECs by Western blotting. (h, i) The EGFR, MMP-2, and MMP-9 proteins were detected in dermal fibroblasts. Results are representative of three experiments. ∗P < 0.05, compared with blank group; ΔP < 0.05, compared with TWEAK alone group; #P < 0.05, compared with TWEAK + control siRNA group. DMEC, dermal microvascular endothelial cell; siRNA, small interfering RNA.
Journal of Investigative Dermatology  , DOI: ( /j.jid )
Copyright © 2018 The Authors Terms and Conditions