Thickening of glomerular capillaries (appear as wire loops)
Characterized by increased glomerular cellularity in more than half of the glomeruli
EM
An immunofluorescence pattern containing IgG, IgM, IgA and C3, C1q is highly characteristic of lupus nephritis and is referred to as a full-house (三带一对, ie, a poker hand with three of a kind 3 immunoglobulin classes and two of a kind 2 complement components).
The full-house pattern reflects the pathogenesis of lupus: loss of immune tolerance to self-antigens (eg, double-stranded DNA) leads to generation of polyclonal autoantibodies that form circulating immune complexes; these deposit in the glomeruli, where they cause local injury by activating the classical complement cascade.
