Fig 2: HGF and c-Met immunostaining in mouse tongue lesions of different groups. Representative IHC images of HGF (A) and c-Met (B).×200. IHC scores of HGF (C) and c-Met (D). 4NQO group, 16 w: n = 8; 20 w: n = 7 (Tg) and n = 8 (Wt); 24 w: n = 6 (Tg) and n = 9 (Wt). Mean ± SEM. Mann–Whitney test. *p < 0.05, **p < 0.01.

Fig 3: HGF and c-Met immunostaining in human normal oral mucosa, paracancerous tissue, and OSCC tissue. ×200 (A). The 5-year overall survival rate of OSCC patients (p > 0.05). Kaplan–Meier analysis (B, C).

Fig 4: cHGF protects against FK506-mediated nephrotoxicity in the allo-OLT rat model via an IL-10-related mechanism. (A) H&E staining to evaluate the CNIT score in renal tissues ( Table 2 ) from the Syn, allo-OLT, and FK506 (scores of 2, 2, and 1) subgroups based on the histologic features shown in Table 2 , specifically proximal tubules with cytoplasmic isometric vacuoles or tv [(i) a blue arrow], tubular atrophy with a striped pattern of interstitial fibrosis [(ii) a blue arrow], and subendothelial, medial, and peripheral arteriolar hyalinosis or ah [(iii) a blue arrow]; n = 6/subgroup. (B) Identical analysis in the cHGF group based on CNIT scores shown in Table 2 as 0; n = 6. (C) IHC staining for KIM-1 in renal tissues from the four subgroups and subsequent analysis showing a higher expression of KIM-1 in the FK-506 group (blue box and bar) than cHGF (blue box, red bar), other [Syn (gray bar), and allo-OLT (black bar)] groups (ii); n = 6/per subgroup. (D) IHC staining for HGF in renal tissues from the same subgroups and analysis of the different HGF expressions among the groups, n = 6/group. (Ei, ii) IHC staining and analysis for IL-10 in the four subgroups of liver allografts (i) and in the two subgroups of FK506 and cHGF of renal tissues (ii) on POD 7; the boxes represent one-sixth area of the whole stained field. (F) ELISAs for serum IL-10 in subgroups (n = 6), including the naive (light gray bars), Syn (gray bars), allo-OLT (black bars), cHGF (red striped bars) and cHGF plus anti-cMet-Ab (solid green striped bars) on POD 7 and 10–12. Original magnification = ×400; scale bar = 200 µm. The data are presented as the mean ± SD of at least three independent experiments. *#p < 0.05 vs. the FK506 or allo-OLT group; **##p < 0.001 vs. the FK506 or cHGF group; ns indicates not significant, p > 0.05.

Fig 5: HGF induced aCD8+ T cell apoptosis in a mechanism mediated by its only receptor cMet. (Ai–iv) Western blot analysis for HGF in liver allografts from recipient rats of the allo-OLT (i) that received FK506 (ii) and cHGF (iii iv) on POD 10–12; n = 6. (Bi–v) IHC staining (brown) for HGF and CD8 in the same area of tissue specimens from the rats subjected to allo-OLT on POD 10–12 (i, boxes) (n = 6/group) and a comparison to the Syn groups on both POD 7 (ii) and 10–12 (iii); the correlations between CD8 and HGF in allo-OLT recipient rats on POD 10–12 (iv), n = 25 points. Western blot analysis was used for the expression of HGF and CD8 in naïve livers (black) and livers from the rats subjected to allo-OLT (red in boxes) on POD 7 and 10–12 (Bv), densitometric quantification showing the decreasing trend in expression. The target protein expression was normalized to the expression of ß-actin; n1 and n2 represent two individual samples; n = 3/time point. Original magnification ×200; scale bar = 100 µm. *#p < 0.05 vs. the Syn group. (Ci, ii) Western blot detection for HGF expression in liver allografts from the recipient rats treated with cHGF plus anti-cMet-Ab (i, the same treatment with cHGF but without the IV injection approach) on POD 7 (n = 6) and survival curve with the MST analysis (ii). n = 16. #p < 0.05 vs. the cHGF group (Student’s t-test). (Di–v) IF staining for aCD8+ T cells (red) in the allo-OLT and cHGF groups at the protein (i, boxes, ii, n = 6) and mRNA (RT-qPCR, n = 3) (iii) levels on POD 7 and the cHGF plus anti-cMet-Ab group (iv, a box, v). (Ei, ii) Analysis of the IF staining of Ki-67 (green) within CD8+ T cells (red) in liver allografts from the allo-OLT and cHGF groups on POD 7 and 10–12 shown in Supplementary Figures S4D —i, ii (i, **p < 0.001 vs. allo-OLT); analysis of TUNEL staining (green) within CD8+ T cells (red) in liver allografts from the allo-OLT and cHGF groups on POD 7 and 10–12 shown in Supplementary Figures S4E —i, ii (ii, **p < 0.001 vs. allo-OLT). Analysis of cHGF plus anti-cMet-Ab (solid blue bars) for CD8+ T cell proliferation (Ki-67) and apoptosis (TUNEL) in Supplementary Figures S4D —iii, iv, Eiii, iv (i, ii, #P < 0.05 and #p < 0.05, ##p < 0.001 vs. the cHGF group), Student’s t-test, n = 6. Original magnification, ×400; scale bar = 200 µm. (Fi–v) Analysis of the serum levels of AST, TBiL, and ALB (i); the cytokines IL-2, TNF-a, and IFN-? (ii) in the naive (light gray bars), Syn (gray bars), allo-OLT (black bars), cHGF (red bars), and cHGF plus anti-cMet-Ab (green bars) subgroups by ELISAs; histological assessment by RAI score [RAISs (0–3) and tRAISs (0–9)] around PVs (a, boxes), BDs (b, boxes) and VEs (c, arrows) from Supplementary Figures S4F —i, ii on POD 7 and POD 10–12 according to Banff’s criteria (iii, #p < 0.05, ##p < 0.001 vs. the cHGF group, Student’s t-test), n = 10/time point, IF staining (n = 6) of cMet (green) in MACS-purified Lewis rat naive splenic CD8 T cells (red) (F—iv, the arrow denotes merged brown staining) and confirmation of cMet expression by Western blot analysis (F—v, n = 3, n1–n3 represent each set of individual cells); the boxes represent one-sixth of whole stained field. Original magnification, ×400; scale bar = 200 µm. The data are presented as the means ± SDs of at least three independent experiments. The asterisks indicate a statistically significant difference.