Abstract
Glomerulonephritis is one of the most important complications of SLE. The genesis of the renal lesions in this disorder is determined by a cascade of events that leads to mesangial cell proliferation as one of the hallmarks of the kidney disease. The current study examines the postulate that there may be intrinsic abnormalities in the mesangial cells of the autoimmune host which predisposes it to develop nephritis. It investigates the possibility that growth responses of mesangial cells of the autoimmune MRL/MpJ-lpr/lpr mice are different from those of their congenic normal MRL/MpJ-+/+ (MRL-++) counterparts when cultured with various cytokines. To test this possibility, growth responses of mesangial cells as assessed by [ super(3)H]TdR uptake were measured when these cells were cultured with epidermal growth factor, platelet-derived growth factor, transforming growth factor- beta , and 1,25-dihydroxy vitamin D sub(3). The response profile of mesangial cells of the MRL-lpr mice suggests that these cells have a tendency to proliferate when they are acted on by cytokines, so that they may be more susceptible to develop the proliferative lesions seen in the nephritis of SLE.