Figure 5.

Upregulation of PN-1, tPA, and PAI-1 protein by cryoglobulin in WT mesangial cells. (A) Western blot analysis. Mouse mesangial cells were incubated with cryoglobulins or HA IgG/IgM or mouse IgG (control Ig) for the indicated time. Cryoglobulin-induced upregulation of PN-1, tPA, and PAI-1 proteins became apparent at 24 h and maximal at 48 h. No significant increase in PN-1 or tPA was observed in mesangial cells incubated with HA-IgG/IgM (shown) or mouse IgG. Similarly, no increase was seen in PAI-1 expression after incubation with mouse IgG. γ-Tubulin was used as an internal control to ensure equal protein loading. (B) PN-1, tPA, and PAI-1 expression. Mesangial cells incubated with cryoglobulins demonstrated upregulated expression levels for PN-1 (2.8-fold), tPA (3.1-fold), and PAI-1 (1.5-fold) compared with control. Values were normalized for differences in protein loading.