Immunofluorescence staining for immunoglobulin and complement deposition on renal histological specimens from DKO and B6.lpr mice of different ages might be able to answer whether immune-complex-mediated mechanism are associated with the age-dependent increase in severe lupus glomerulonephritis in the absence of CD137L in the B6.lpr mice. This evidence concerns the gene TNFSF9 and lupus nephritis.