Figure 3From: Relative percentage and zonal distribution of mesenchymal progenitor cells in human osteoarthritic and normal cartilageImmunohistochemical staining of normal and osteoarthritis (OA) chondrocytes after isolation and initial adherence. Representative images of an OA chondrocyte sample are shown in (a-d); staining results for normal chondrocytes were identical (not shown). Nuclei were visualized with DAPI (4',6-diamidino-2-phenylindole) (a). Cell membranes were double-stained for CD105 by using an Alexa Fluor 488-coupled secondary antibody and for CD166 by using an Alexa Fluor 594-coupled secondary antibody and analyzed by fluorescence microscopy. Co-expression of CD105 and CD166 was identified after computed superimposition of fluorescence signals from both channels. Almost all cells are CD105+ (b), whereas only a few cells express CD166 (c); but in all cases, this is accompanied by the co-expression of CD105 (d). In addition, the results of the quantitative analysis of normal (e) and OA (f) chondrocytes are shown. Magnifications: 100 ×, 400 × (insets). SEM, standard error of the mean.Back to article page