Early Humoral-Mediated Graft Injuries in ABO-Incompatible Kidney Transplantation in Human Beings

• Published in: Transplantation proceedings 2010-04, Vol.42 (3), p.789-790
• Main Authors: Sekijima, M, Shimizu, A, Ishii, Y, Kudo, S, Horita, S, Nakajima, I, Fuchinoue, S, Teraoka, S
• Format: Article
• Language: English
• Subjects: ABO Blood-Group System - immunology; Adult; Biological and medical sciences; Biopsy; Blood Group Incompatibility - immunology; Blood Group Incompatibility - pathology; Complement C4b - analysis; Creatinine - blood; Fluorescent Antibody Technique; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Humans; Immunity, Humoral; Kidney Glomerulus - injuries; Kidney Glomerulus - pathology; Kidney Transplantation - immunology; Kidney Transplantation - pathology; Kidney Transplantation - physiology; Medical sciences; Middle Aged; Peptide Fragments - analysis; Postoperative Complications - immunology; Postoperative Complications - pathology; Surgery; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surgery of the urinary system; Tissue, organ and graft immunology; Treatment Outcome
• ISSN: 0041-1345; 1873-2623
• DOI: 10.1016/j.transproceed.2010.02.054

Abstract Introduction Acute humoral rejection is the most important risk factor for early graft loss in ABO-incompatible (ABO-i) renal transplantation (RTx) and is present from the early period after RTx. However, the characteristics of early humoral-mediated graft injury are pathologically uncertain. Objective To analyze tissue from 10 protocol graft biopsies performed in 10 patients within 30 days post-RTx to clarify the pathologic features of early humoral-mediated graft injuries in ABO-i RTx. Methods Pathologic findings were examined using light and electron microscopy and immunofluorescence studies for C4d. Protocol biopsies were performed within 30 days after RTx in the absence of an episode of dysfunction (creatinine concentration 1.21–1.81 mg/dL). Results The immunofluorescence study demonstrated C4d deposition in peritubular and glomerular capillaries. Acute glomerulitis with infiltration of mononuclear cells and neutrophils was observed in 3 patients. Furthermore, glomerulitis was accompanied by endothelial cell injuries, widening of subendothelial spaces with a double-contoured glomerular basement membrane, and mesangiolysis. Conclusion In ABO-i RTx, early humoral-mediated graft injuries were observed in approximately 30% of patients despite normal graft function. They were characterized by C4d deposition and glomerular capillary injury. These findings suggest that renal glomeruli are the first site of graft injury by anti-A or anti-B blood type antibody with complement activation in ABO-i RTx.