(A) Western blotting and densitometric quantification (right) of NT3 in BMMCs after LPS (100 ng/mL) or RD (1 μM) treatment for 1 hour, with β-actin as the loading control, n = 3 biological replicates. (B and C) Representative (B) expression of Tlr4 (P_adj > 0.05, log₂FC < 1) in the GSE64287 dataset, confirmed by (C) Western blotting. (D) Western blotting and densitometric quantification (right) of LPS competitive binding to His-tagged or Fc-tagged TrkA in vitro (n = 3 biological replicates). (E) Binding model for LPS (yellow) with TrkA (purple), showing key atoms in LPS (blue sticks) and residues in TrkA (green sticks). (F–I) Representative (F) planar chemical structure, (G) lowest free energy 3D structure of LPS, (H) hydrogen bonds between LPS and TrkA in lipid A (red arrows) or PS (black arrow), and (I) schematic of LPS delipidation strategy. (J) Western blotting and densitometric quantification (right) of TrkATyr490 in BMMCs after treatment with LPS, PS, or rmNGF for 1 hour, with β-actin as the loading control, n = 3 biological replicates. (K and L) Western blotting and quantification (right) of NT3 in BMMCs after pretreatment with LPS (100 ng/mL) or PBS, followed by treatment with rmNGF (0–100 ng/mL) or GW (1 μM) for 1 hour, with β-actin as the loading control, n = 4 biological replicates. (M) IF double-staining images and quantification (right) of CAM1⁺ (green)/NT3⁺ (red) cells in injured tendon sections, with DAPI counterstaining (blue). Scale bar: 5 μm (left) and 1 μm (right), n = 5 biological replicates. Data are representative of 2 independent experiments (A–D and J–M). Data shown as mean ± SD, compared by Student’s t test (B–D) or 1-way ANOVA (J–M).