Fig. 3

Influence of rHc-MMP-12 on different functions of goat peripheral blood mononuclear cells (PBMCs). a Binding of rHc-MMP-12 with PBMCs. PBMCs were cultured with rHc-MMP-12 (10 μg/m) and without protein as control at 37 °C and 5% CO₂. After 2 h incubation of PBMCs with rHc-MMP-12, rat anti-rHc-MMP-12, or negative rat IgG (as first antibody) was added, followed by staining with Cy3-conjugated secondary antibody and DAPI. Red fluorescence on surface of cells shows target protein staining (Cy3) and cell nuclei were visualized by DAPI (blue). No red fluorescence was observed in control groups. b Influence of rHc-MMP-12 on PBMCs proliferation. Cells were incubated with different concentrations of rHc-MMP-12, purified pET32a protein and PBS (control) at 37 °C and 5% CO₂ for 72 h. Cell proliferation index was calculated considering the optical density (OD 450) values in PBS control as 100%. c Influence of rHc-MMP-12 on nitric oxide production by PBMCs in vitro. Cells were incubated with PBS, pET32a and serial concentrations of rHc-MMP-12 protein for 24 h in 37 °C and 5% CO₂. The nitrate concentration in the PBMCs was measured by using the Griess assay. Statistically significant differences between the means of three independent experiments were assessed using a one-way ANOVA (*P < 0.05, **P < 0.01, ***P < 0.001; ns, no significant difference)