CD2AP depletion impairs the adhesion and spreading function of podocyte / 中华肾脏病杂志

ABSTRACT

Objective To study the effects of CD2-associated protein (CD2AP) on podocyte adhesion and extension ability and to explore its possible mechanism. Methods Conditionally immortalized murine podocyte cell line was cultured in RPMI 1640 medium at 33℃permissive conditions. The podocytes were transfected with CD2AP small interfering RNA (siRNA) and serambing sequences labeled with fluorescein were taken as control. The transfected podocytes were trypsinized and seed into collagen IV coated plates. The relative cell adhesion and cell area were examined 90 min later. Apoptotic rates of CD2AP siRNA transfected podoeytes and different PAN concentrations incubated podoeytes were detected by flow cytometer. The distribution of F-actin was observed under laser scanning confoeal microscope. Nephrin protein expression and its phosphorylation level were examined by immunofluorescence and Western blot. Results The relative ceil adhesion of CD2AP siRNA transfected podocytes was apparently lower than that of control group[(41.72±6.07)% vs (64.46±8.53)%, P<0.05]. The cell area analysis had the similar result. The apoptotic rate of CD2AP siRNA transfected podocytes was significantly higher than that of the controls [(5.73±0.61)% vs (3.26±0.45)%, P<0.05]. 100 mg/L PAN could markedly induce podocytes to apoptosis and impair cell adhesion ability (P<0.05). Nevertheless, no significant difference was found in cell body spreading (P>0.05). The distribution of F-actin in CD2AP depletion podocytes was apparently altered. The expression of nephrin protein and its phosphorylation level was conspicuously descended to some degree (P<0.05). Conclusions CD2AP depletion facilitates podocyte apoptosis and impairs cell adhesion function. Cytoskeleton confusion and nephrin signaling weakness caused by CD2AP depletion may he partly responsible for the decline of cell adhesion and spreading.