CD40LG and lupus nephritis: Circulating IgG and IgM antibodies against these peptides were also detected in patients with idiopathic membranous nephropathy (IgG: 1/18, 5.6%; IgM: 1/18, 5.6%), primary focal segmental glomerular sclerosis (IgG: 2/32, 6.3%; IgM: 7/32, 21.9%), minimal change disease (IgM: 1/21, 4.8%), IgA nephropathy (IgG: 2/20, 10%; IgM: 0/20, 5%), and lupus nephritis (IgG: 2/20, 10%; IgM: 1/20, 5%).