CD2-associated protein (CD2AP) is an 80-kilodalton protein that is critical
for stabilizing contacts between T cells and antigen-presenting cells. In
CD2AP-deficient mice, immune function was compromised, but the mice died at
6 to 7 weeks of age from renal failure. In the kidney, CD2AP was expressed
primarily in glomerular epithelial cells. Knockout mice exhibited defects
in epithelial tell foot processes, accompanied by mesangial cell hyperplasi
a and extracellular matrix deposition. Supporting a role for CD2AP in the s
pecialized cell junction known as the slit diaphragm, CD2AP associated with
nephrin, the primary component of the slit diaphragm.