Pathology of antibody-mediated rejection in renal allograft / 器官移植

Antibody-mediated rejection (AMR), also known as humoral rejection, is an immune injury caused by rejection involved with multiple humoral immune effectors, such as antibodies and complements, etc. AMR plays a pivotal role in hyperacute, acute and chronic rejection. In this article, the basic definition of AMR, the research progress and major achievements on AMR pathology according to Banff classification on allograft pathology (Banff classification), and main pathological characteristics of AMR in renal allograft were reviewed, aiming to provide reference for accurate diagnosis and timely treatment of AMR, and guarantee the long-term survival of renal graft and recipients.

Pathology of T cell-mediated rejection in renal allograft / 器官移植

T cell-mediated rejection (TCMR) is one of the main mechanisms of rejection in organ transplantation, which is also the most common type of acute rejection.Based on Banff classification on allograft pathology (Banff classification) in 2019, TCMR can be divided into acute TCMR (aTCMR) and chronic active TCMR (caTCMR) according to the characteristics of immune lesions.In this article, the basic definition of TCMR, the research progress on TCMR pathology according to Banff classification for renal allograft, and the basic pathological changes and diagnostic grading of TCMR were reviewed, aiming to provide evidence for early identification, diagnosis and treatment of TCMR and prevent the progression of TCMR into caTCMR, thereby guarantying the long-term survival of both the renal allograft and recipient.

Progress on electron microscopy diagnosis on Banff classification for renal allograft pathology / 器官移植

With the development of organ transplantation in clinical practice, allograft pathology has been constantly developing and advancing. The convening of Banff conference on allograft pathology and the establishment of Banff classification on allograft pathology (Banff classification) are pivotal milestones in the development of international allograft pathology. Since then, Banff classification on pathological diagnosis of various transplant organs have been continually updated and improved. Ultrastructural pathological observation by electron microscope plays an irreplaceable role in the early diagnosis of antibody-mediated rejection, recurrent disease and de novo disease of renal allograft. Early detection and rational treatment help to maintain the long-term survival of renal allograft and reduce the failure of renal allograft. In this article, the basic definition of electron microscope and the ultrastructural pathological diagnosis, the research history and main progress on electron microscope diagnosis on Banff classification for renal allograft pathology were introduced, and typical pathological changes, specific terminology and diagnostic criteria of electron microscope diagnosis on renal allograft biopsy were summarized, aiming to provide reference for clinical and basic research of organ transplantation.

The Significance of Adhesion Molecules and Granzyme B in Acute Renal Allograft Rejection

Intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) are weakly expressed in normal glomerular cells and vascular endothelial cells, but not in tubules. Granzyme B is a cytotoxic granule present in activated cytotoxic T cells and natural killer cells. To determine the effect of ICAM-1 and VCAM-1 expression and granzyme B-positive cells on histologic grade of rejection, we performed the immunohistochemical study on 19 renal biopsy specimens and one nephrectomy specimen from 14 patients with acute renal allograft rejection using monoclonal antibodies against theses proteins. According to severity of rejection based on Banff classification, three biopsies were classified as borderline, 4 grade I, 12 grade II, and 1 grade III. In all the cases with acute rejection, ICAM-1 and VCAM-1 were expressed in the tubular epithelial cells. The numerical score of ICAM-1 in the tubular epithelial cells was 1.0 in borderline cases, 1.3 0.4 in grade I cases, 2.2 0.8 in grade II cases, and 3.0 in grade III case. The staining intensity of ICAM-1 in the tubular epithelial cells was increased in accordance with histologic rejection grade (P<0.05). The staining intensity of ICAM-1 and VCAM-1 in the renal tubular epithelial cells was increased in accordance with the number of T lymphocytes in the renal parenchyme (r=0.46; P<0.05, r=0.61; P<0.01). The number of granzyme B-positive cells was 6.4 1.6/HPF in borderline cases, 8.1 2.5 in grade I cases, 19.6 11.7 in grade II cases, and 53 in grade III case. The number of T lymphocytes and granzyme B-positive cells was also increased in accordance with histologic rejection grade (P<0.05). These results suggest that ICAM-1 and granzyme B-positive cells may play an important role in the induction of renal allograft rejection and that the grading of severity of these parameters may be useful to predict the prognosis of renal allograft.

Correlation of Pathologic Staging by Banff Criteria with Rejection Reversal and Graft Outcome in Acute Renal Allograft Rejection / 대한이식학회지

PURPOSE: Acute renal allograft rejection is known to be an important prognostic factor of long-term graft survival. The purpose of this study was to make a treatment discipline in acute renal allograft rejection by finding any relationship between Banff classification of acute rejection and response to treatment and long term graft survival. MATERIALS AND METHODS: Thirty-eight cases histopathologically diagnosed as acute rejection were included in this study. The grade of acute rejection was classified according to Banff criteria (1997). Response to treatment was classified into three groups; complete (>75% reduction in serum creatinine increment), partial (25-75% reduction), and no response (>25% reduction). RESULT: Mean age of the patients at the time of biopsy was 32.3 years and male to female ratio was 25:13. The mean interval between renal transplantation and rejection episode was 4.9 months. Mild, moderate and severe rejection according to Banff classification was 15, 15 and 8 cases respectively. Antirejection therapy with steroid pulse was initiated in all cases, antilymphocyte globulins (ALG or OKT3) in 19 cases and tacrolimus rescue therapy in one. All patients except for two (93%) with mild or moderate rejection showed complete or partial response, whereas responsiveness was noted only in three cases (38%) with severe rejection (p>0.01). 66.7% of cases with mild rejection showed complete response to steroid pulse therapy; 40% with moderate rejection; 0% with severe rejection (p=0.01). Patients with severe rejection had much poorer long term graft survival than with mild or moderate rejection (p=0.01). CONCLUSION: These results suggest that Banff classification of renal allograft rejection could be used as an indicator of treatment responsiveness and graft prognosis. They also suggest that a more intensive anti-rejection therapy should be recommended in high grade rejections.