title: C4d deposition and multilayering of peritubular capillary basement membrane in posttransplantation membranous nephropathy indicate its association with antibody-mediated injury.
abstract: Membranous nephropathy (MN) may develop as recurrence or de novo after transplantation. Recently, autoimmune or alloimmune responses to unspecified glomerular antigens have been considered as a pathogenetic mechanism. To explore the relationship between antibody-mediated injury and posttransplantation MN, we tested C4d positivity using polyclonal antibody in renal allograft biopsy samples diagnosed as posttransplantation MN. A total of 19 cases (16 males and 3 females), including 2 recurrent and 7 de novo forms, were the subject of the study. On light microscopy, stage II was the most common (n = 9). In addition to glomerular capillary immunoglobulin (Ig)G deposits, all but 2 cases having only sclerotic glomeruli were C4d-positive in glomerular capillary walls. Twelve cases were also positive in cortical peritubular capillaries (PTCs): diffuse in 8 cases and focal in 4 cases. Two of 3 cases associated with acute rejection and 3 of 4 cases associated with chronic rejection were PTC C4d-positive. The frequency of C4d positivity in PTCs was significantly higher than that of posttransplantation IgA nephropathy (P = .028). In conclusion, a higher frequency of PTC C4d positivity suggests an involvement of chronic antibody-mediated injury in the evolution of posttransplantation MN.
authors.affiliation: Department of Pathology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: B J
authors.initials: BJ
authors.lastname: Lim
authors.forename: M S
authors.initials: MS
authors.lastname: Kim
authors.forename: Y S
authors.initials: YS
authors.lastname: Kim
authors.forename: S I
authors.initials: SI
authors.lastname: Kim
authors.forename: H J
authors.initials: HJ
authors.lastname: Jeong
mesh_terms: D000328:Adult; D001323:Autoantibodies / Q000276:immunology*; D001485:Basement Membrane / Q000378:metabolism*; D015935:Complement C4b / Q000378:metabolism*; D005260:Female; D015433:Glomerulonephritis, Membranous / Q000276:immunology*; D006801:Humans; D007150:Immunohistochemistry; D016030:Kidney Transplantation / Q000276:immunology*; D008297:Male; D010446:Peptide Fragments / Q000378:metabolism*
chemical_list: D001323:Autoantibodies; D010446:Peptide Fragments; D015935:Complement C4b; C032261:complement C4d