Figure 1. Stem/progenitor cells (SPCs) in culture and atherosclerotic lesions express matrix metalloproteinase-8 (MMP8).
A, Bone marrow (BM)–derived leukocytes (CD45+), BM-derived stem cells (CD34+ and Sca-1+), embryonic stem (ES) cell–derived Sca-1+
SPCs, endothelial cells (ECs), and smooth muscle cells (SMCs) express MMP8, as demonstrated by Western blot analysis. B, ES cell–
derived Sca-1+ SPCs express MMP8, as demonstrated by immunofluorescence staining. C, Oxidized low-density lipoprotein constituents
induce MMP8 expression. Cultured Sca-1+ SPCs were treated with various amounts of the oxidized low-density lipoprotein constituents
4-hydroxynonenal and 7-ketocholesterol for 24 hours, followed by reverse-transcriptase polymerase chain reaction (RT-PCR) analysis
of MMP8 gene expression. D, SPCs in atherosclerotic lesions express MMP8. ApoE−/−/MMP8+/+ mice were fed a Western diet for 12
weeks, and sections of the aortic roots were subjected to double immunofluorescence staining for MMP8 and Sca-1. White arrows in
the immunofluorescence image indicate double-positive cells in the lesion. Right, Gray-field image of the same section. Red dotted line
indicates the boundary between the lesion and healthy area.
