MLECs derived from CD151-deficient mice show higher MMP2 activity. (A) Western blot analysis of the expression of MT1-MMP and CD151 in total lysates of MLECs derived from WT or CD151-deficient animals (CD151 KO). Vimentin is shown as loading control. (B) Immunofluorescence staining of the endothelial specific markers VE-cadherin and CD31 in MLECs derived from WT and CD151-deficient mice. Nuclei were stained with Hoechst (blue). (C) Gelatin zymography of culture supernatants of MLECs derived from WT or CD151-deficient mice. Numbers depict the quantification of the gelatinolytic activity of mature MMP2 in the experiment shown. The chart below depicts the mean gelatinolytic activity of mature MMP2 normalized with respect to cells derived from WT mice plus or minus SE. *P < .05, Student t test.