Figure 5.

Qualification of primary mesangial cell cultures. I: Immunostaining results for a typical primary mesangial cell preparation is shown. A, Anti-desmin; B, anti-fibronectin; C, anti-smooth muscle actin; D, anti-vimentin; E, anti-von Willebrand factor (a marker for endothelial cells). Cells were negative for podocyte markers podocin, nephrin, and CD2AP (not shown). II: FACS analysis of wild-type and integrin α1-null mesangial cells using anti-α1 integrin antibodies. Primary cultured mesangial cells from either wild-type (IIA) or integrin α1-null (IIB) mice were reacted with either a monoclonal antibody specific for α1 integrin (solid lines) or a nonreactive isotype-matched control antibody (dashed lines). After reaction with a fluorescein isothiocyanate-conjugated secondary antibody, immunopositive cells were detected by fluorescence-activated cell sorting. Histograms represent a gated population of live mesangial cells and are representative of three independently conducted experiments from distinct culture derivations. Original magnifications, ×630.