Introduction

Abstract

This supplement contains the proceedings of the 13th Japanese Clinico-Pathological Conference on Renal Allograft Pathology, which was held on July 18, 2009, in Tokyo, Japan. The importance of kidney transplant pathology to evaluate graft condition and select optimal therapy has been widely acknowledged. The conference on renal allograft pathology has been held every year since 1997, and clinical nephrologists, transplant surgeons, urologists, and renal and general pathologists in Japan discuss renal transplant cases and topics related to renal transplantation. Every year’s conference has included unique topics concerning renal transplantation and provided an opportunity for debate from residents and fellows to specialists in pathology, internal medicine, and surgical fields. This year’s conference consisted of four special mini-lectures and 22 scientific studies and case presentations. Before the session, attendees could view all of the renal allograft case samples via a virtual microscope system at the front of the conference room. In addition, the histopathological features of two cases were discussed using virtual slides and a high-definition television system. The theme of the special mini-lectures in this meeting was “New therapeutic strategy for renal transplantation: Induction of tolerance in clinical and preclinical kidney transplantation.” In particular, the lecture “Induction of tolerance in clinical kidney transplantation” presented by Dr. Kawai from Massachusetts General Hospital/Harvard Medical School, Boston, USA, was quite educational for us in terms of the next practical and ideal strategy for kidney transplantation. Drs. Bashuda (Juntendo University, Tokyo, Japan) and Yamashita (Hokkaido University School of Medicine, Hokkaido, Japan) presented new strategies using adoptive transfer of regulatory T-cell-like cells (anergic cells) or anti-CD40 monoclonal antibody in preclinical studies, using non-human primates. For scientific studies and case presentations, we prepared five topics for detailed discussion: ABO-incompatible transplantation, acute antibody-mediated rejection, acute T-cell-mediated rejection, post-transplant glomerulonephritis, and pathology of surgical complications and others. Within each heading, four to five cases or studies were presented and discussed clinico-pathologically. Under the topic “ABO-incompatible transplantation,” pathology within 90 d of transplantation was characterized, and the very rare cases that show hyperacute rejection and acute antibody-mediated rejection in Epstein syndrome with thrombocytopenia were reported. Other topics included acute antibody or cell-mediated rejection. The clinico-pathological characterization of acute vascular rejection was discussed, and cases showing BK virus infection and plasma cell-rich acute rejection were reported. Under the topic “post-transplant glomerulonephritis,” the pathology and treatment of recurrence or de novo focal glomerulosclerosis (FSGS) and essential cryoglobulinemia were discussed. “Pathology of surgical complications and others” covered cases of pregnancy-induced thrombotic thrombocytopenic purpura and anemia-associated progressive interstitial fibrosis after transplantation, and the usefulness of baseline renal biopsy in the evaluation of the condition of living donor kidneys was reported. From the discussion of the scientific studies and transplant cases, we reconfirm that the examination of renal morphology in allograft patients is essential to evaluation of graft condition and achieving appropriate therapy. We believe that the reports appearing in this supplement address the above-mentioned issues that are important to the field of renal transplantation. The guest editors thank all authors and participants for their contributions. We also gratefully acknowledge the outstanding effort and support of Novartis Pharma K.K. (Japan) in holding this meeting. In addition, the sponsorship of the many cooperating firms listed on the title page made it possible to hold the meeting and publish this supplement. Finally, I express my sincere appreciation to Dr. Morozumi and Dr. Yamaguchi for their dedication to this meeting.