佐久間 康成

INTRODUCTION: According to the Japanese renal transplant registry 2005, 834 transplantations were performed using living donors. Among them 112 (13.4%) patients were transplanted from living donors before the initiation of maintenance dialysis. Preemptive kidney transplantation (PreKTx) has been associated with improved allograft and patient survival rates compared to non-PreKTx. This study was designed to summarize our experience with PreKTx. PATIENTS AND METHODS: From April 2003 to July 2007, 44 living kidney transplantations were performed at our institution. We divided these 44 patients into two groups: 5 (11.4%) patients (group 1; G1) who underwent PreKTx and the other 39 patients (group 2; G2) who received kidneys after the institution of maintenance dialysis. Living unrelated donors were mostly spouses. During the induction phase, tacrolimus or cyclosporine, mycophenolate mofetil, and methylprednisolone were used for immunosuppression. In ABO-incompatible cases, plasmapheresis was performed to remove anti-AB antibodies prior to transplantation and splenectomy at the time of or before transplantation. RESULTS: Among G1, no patient died. Among G2, two patients died with functioning grafts, one due to a traumatic subdural hematoma and another due to malignant B cell lymphoma. Death-censored graft survival rates were 100% in both groups. The incidence of acute rejection was 20.0% and 20.5% in G1 and G2, respectively. CONCLUSIONS: Our results demonstrated that PreKTx from a living donor was equivalent to the non-PreKTx. However, there were also potential benefits to PreKTx in the long-term outcome, including avoidance of morbidity associated with dialysis and access procedures, as well as reduced cost. In response to the shortage of deceased donors, PreKTx from living donors will spread in Japan.

BACKGROUND: The quality and stability of enzyme blends used in islet cell processing are critical for successful human islet isolation. A wide variability in enzymatic activity among lots of Liberase HI has been reported. This study examines the interlot and intralot variability of Liberase HI and the over-time deterioration of enzyme quality based on the analysis of islet isolation outcomes. METHODS: The data of 169 human isolations processed for clinical islet transplantation, using five different lots of Liberase HI, were retrospectively analyzed. Inter- and intralot variables in the islet isolation were assessed over a 15-month period. RESULTS: The analysis revealed significant interlot differences in the digestion time, prepurification islet counts, percent recovery, viability, and glucose stimulation insulin index. Moreover, a significant decrease in the pre- and postpurification islet yield per pancreas weight (IEQ/g) in isolations processed by two different enzyme lots used over a 15-month period was observed, suggesting a progressive deterioration of enzyme quality. CONCLUSIONS: Our data demonstrate a significant lot-to-lot related variability in islet isolation outcomes. In addition, the over-time decline in isolation outcomes processed using a single enzyme lot was observed even when the enzyme blends were used within the expiration dating specified by the manufacturer.

PURPOSE: We assessed the feasibility of retroperitoneoscopic hand-assisted live-donor nephrectomy according to the basic principle of transplantation in kidney selection, namely, leaving the better-functioning kidney in the donor. PATIENTS AND METHODS: Thirty consecutive live-donor nephrectomies, including 10 right-sided and 20 left-sided procedures, were evaluated. The surgery was started endoscopically using three ports, followed by hand assistance for dissecting the renal pedicles through the extended inner-port incision. A vascular Endostapler and polymer clips were used to transect the renal vessels. RESULTS: Two right-sided cases required open conversion because of multiple renal vessels and uncontrollable bleeding. The median operative time, warm ischemia time (WIT), blood loss, and renal vein length were 244 minutes (upper and lower quartile 215 and 274 minutes), 186 seconds (134, 239 seconds), 175 mL (45, 305 mL), and 22 mm (19, 26 mm), respectively. The operative time and WIT were longer, and the renal vein was shorter, in the right-sided than in the left-sided procedures (P < 0.05), but no difference was found in the other perioperative data for the two sides. No delayed graft function was observed, and the kidney function 1 month postoperatively was acceptable in all donors and all recipients. CONCLUSION: Our technical devices, such as the site and timing of hand assistance and control of the renal vessels, seem feasible. Although we could not draw a conclusion about the safety of the right-sided procedure, this alternative procedure should be applicable for laparoscopic donor nephrectomy uninfluenced by the side of the donor kidney provided the surgical team has sufficient expertise.

A living kidney donor surgery must be safe and minimally invasive. In addition the removed kidney must be in good condition. Retroperitoneoscopic nephrectomy has the advantage that it does not risk intra-abdominal organ injuries and provides direct access to the renal artery/vein despite the small working space. An abdominal wall-lifting method combined with the pneumoretroperitoneum provides sufficient space to use a hand skillfully in retroperitoneoscopic surgery. Introduction of hand-assisted retroperitoneoscopic living donor nephrectomy with the abdominal wall-lifting method yielded safer and easier operations as well as shorter warm ischemia (mean: 3 minutes; 7 seconds) and operative times (mean: 3 hours; 28 minutes) in the current 10 cases. The procedure is a useful alternative to procure a kidney graft.

BACKGROUND: Multilineage chimerism is a promising strategy to induce donor-specific tolerance. Because the beneficial effect of splenic grafting on tolerance induction is well known, we studied long-term hematopoietic chimerism and the fate of donor-derived cells after allogenic pancreas/spleen transplantation. METHODS: Green fluorescent protein (GFP) transgenic (Tg) Wistar rats were donors and combined pancreas/spleen transplantation (PST) or pancreas transplantation (PT) alone was performed on recipient LEW rats. Graft survival was compared between these two groups and the fate of donor-derived GFP(+) cells was analyzed by flow cytometry. In this system, the donor-derived cells were clearly defined as having lymphocytic or granulocytic lineage by cell size. T-cell subsets of GFP(+) and GFP(-) cells in long graft-surviving rats were also characterized. RESULTS: The survival period of the grafted pancreas in PST rats was significantly longer than that of PT rats (P<0.001). Three of seven PST rats survived >250 days. The chimeric level of donor-derived GFP(+) cells in the recipient peripheral blood was markedly higher in PST rats. In rats with long-surviving grafts, overall peripheral blood chimerism was more than 5%, and both lymphocytes and granulocytes generated from the grafted spleen were stable. T-cell subsets in the recipient LEW rats varied according to the type of cells. CD4(+)CD8(+) subsets decreased in the GFP(+) cells and CD4(-)CD8(+) subsets increased in the GFP(-) (LEW) cells. CONCLUSION: We confirmed the combination effect of the grafted spleen on pancreatic graft survival. Donor lymphocytic and granulocytic lineages were generated in the recipients with long-surviving graft. It suggested that multilineage chimerism was often induced by the spleen graft and protected the pancreatic graft against rejection for a long period.

Background: Intestinal grafts greatly affect nutrition and immunology in the host. The growth of the recipient and incidence of graft-versus-host disease depend on graft length. A larger graft may affect the host immune system, but little is known about how the length of the intestinal graft severely affects surgical intervention. We developed a cervical small bowel transplantation (SBT) rat model that minimized technical variations using a cuff method and studied the effects of graft length on surgical damage in SBT. Materials and methods: We transplanted a whole (70 cm) or partial (15 cm) intestine into a syngeneic rat combination of LEW (MHC haplotype: RT1(1)) to LEW and evaluated changes in perioperative hemodynamics and the endogenous endotoxin level. Natural killer (NK) cell activity in the peripheral blood and the immunologic response of the recipient spleen were also studied. Results: In the whole SBT model, body weight loss was more severe than in the segmental SBT model; the rats in the former model often died, while all in the latter survived indefinitely. The systemic blood pressure markedly decreased in the whole SBT group immediately after reperfusion. The proliferative activity of splenic lymphocytes stimulated by concanavalin A was also more severely inhibited in the former model than in the latter postoperatively. NK cell activity in the whole SBT rats declined more severely than the segmental SBT rats 3 days postoperatively. Conclusion: The longer graft severely induced surgical intervention; and influenced host immunosuppression, resulting in the higher mortality in rats undergoing whole SBT. (C) 2003 Elsevier Science B.V. All rights reserved.

BACKGROUND: Composite tissue allografts are unique because they provide the vascularized bone marrow with stroma, which is the supportive microenvironment. In this study, we investigated the beneficial effect of donor-derived bone marrow cells within the long-surviving recipient rats after limb transplantation. METHODS: Green fluorescent protein (GFP) transgenic rats developed for paramount cell marking were donors, and wild Wistar rats were recipients. Orthotopic hind-limb transplantation was performed using a microsurgical technique. Tacrolimus (1.0 mg/kg) was intramuscularly injected for 14 days postoperatively. The skin graft from GFP donor onto the GFP recipient was performed as a control. Flow cytometric analyses of recipient peripheral blood and bone marrow were carried out at 4 to 6 days, 18 to 21 days, 6 weeks, and 2, 4, 6, 9, and 12 months after transplantation. RESULTS: The rats that received tacrolimus therapy achieved prolonged composite graft acceptance more than 12 months, whereas GFP skin grafts were rejected at 47 days under the same immunosuppressive protocol. Numerous GFP lymphocytes and granulocytes were detected within the recipient bone marrow for the first 6 weeks post limb transplantation. These cells remained relatively stable for more than 12 months. CONCLUSIONS: The results showed that donor-derived hematopoietic stem cells engrafted in recipient bone marrow and differentiated to lymphocytes and granulocytes after limb transplantation. The vascularized bone marrow, transplanted as a part of the hind limb, could have contributed to mixed chimerism and worked as the bone-marrow source in the recipients.

Although a short course of methotrexate (MTX) has a potential immunoregulatory effect on clinical allograft rejection, little data are available about the drug, and the mechanism of hyporeactivity after withdrawal is still unknown. In previous studies, we achieved permanent graft acceptance through administration of a short course of high-dose MTX during heterotopic ratheart transplantation (HHT) in a combination of DA (MHC haplotype; RT1(a)) to PVG/c (RT1(c)) rats. A 3-week course of MTX (0.25 mg/kg/day) was administered intraperitoneally to the PVG/c recipients of a DA heart graft, and 11 of 16 rats survived longer than 300 days after HHT. The splenic lymphocytes obtained from one recipient showed high reactivity against donor type splenic lymphocytes, but others did not. All serum samples from recipients showed immunosuppressive activity. The serum had anti-donor antibodies. These results showed that tolerance induced by short-course MTX was maintained by a serologic factor believed to be anti-idiotypic antibodies.

Neoral®, developed as a new galenical formulation of Sandimmune®, successfully improves bioavailability after oral administration of cyclosporine. Clinically, conversion from Sandimmune to Neoral has been done at the same dosage. However, several reports recently showed the adverse effects of this substitution, speculating the significant enhancement of the absorption profile of Neoral. In the present study, we experimentally showed the toxicity and efficacy of the high dose of cyclosporine in the rat, comparing Sandimmune with Neoral. Twenty-five mg/kg of cyclosporine (Sandimmune or Neoral) was administered orally for 14 days to the adult inbred rat of LEW strain (n=5 in each). Changes in the body weights were observed. At the day 14, the trough level concentration of cyclosporine and hematoselorogical data were measured. In other animals, the pharmacokinetic profiles of 25 mg/kg of Sandimmune or Neoral were studied (n=5 in each). Then, in a high responder combination of DA to LEW, pancreas/spleen graft was transplanted into the streptozotocin-induced diabetic rats. The results showed that the body weight gain of the normal LEW rat was significantly suppressed in the Neoral group, compared with that of the Sandimmune group. However, hematoselorogical studies showed no statistical difference between two groups. Pharmacokinetic studies in rats showed that the area under the curve of concentration (AUC0-24) of Neoral was significantly higher than that of Sandimmune. The final experiment showed that both the cyclosporine formulations prolong the pancreatic graft survivals at a high dose, while higher mortality was observed in the Neoral group than in the Sandimmune group. These data indicate that a better absorption profile of cyclosporine was achieved by conversion to Neoral, but must consider the quality of the patient who may be resistant to cyclosporine sensitivity.

Pancreas grafts do not survive for lengthy periods, especially in a high-responder rat combination. Recent data indicated that a combined spleen/pancreas graft protects against acute graft rejection and induces donor-specific tolerance. In this study, we performed a combination spleen/pancreas transplantation using high-dose tacrolimus in a high-responder rat combination of DA (RT1a) to LEW (RT1) and induced permanent survival in the few recipient rats. In these recipients, there was no difference in the mixed lymphocyte reaction (MLR) of the recipients when compared with that of the naive LEW splenic cells, but MLR inhibition by the serum from the recipients was significantly decreased. We also performed immunoblotting and detected a protein that has an affinity for the anti-DA class antibody. This protein may be an anti-idiotypic antibody and contribute to donor- and tissue-specific tolerance.

右上葉気管支内腔に限局し, 充満性に発育した腎癌の転移性気道腫瘍に対し右上葉管状切除術を施行した1例を報告する.<BR>症例は, 53歳男性で, 喀血, 腫瘤の喀出を主訴に外来受診した.既往歴では, 8年前に左腎癌にて腎摘出術を行なっていた.<BR>気管支鏡では, 疣贅状の腫瘤が右上幹入口部を完全に閉塞し, 一部主幹に突出していた.喀出した腫瘤の組織診で, 腎癌の転移性気道腫瘍と診断した.全身検索の結果, 局所再発, 多臓器転移を認めず右肺上葉管状切除術, 縦隔リンパ節郭清を施行した.<BR>病理組織では, clear cell carcinomaが右B¹, B²の気管支内腔に限局し, 充満するように発育していた.術後5年再発徴候は認められない.<BR>転移性気道腫瘍としては, 腎癌は多く報告されているが本例の如く, 肺実質内への侵襲がなく気道内腔に広汎に発育した特異な転移形式を認めた症例は珍しく文献的考察を加え報告する.

The purpose of this study is to evaluate green fluorescent protein (GFP) transgenic rats for use as a tool for organ transplantation research. The GFP gene construct was designed to express ubiquitously. By flow cytometry, the cells obtained from the bone marrow, spleen, and peripheral blood of the GFP transgenic rats consisted of 77, 91, and 75% GFP-positive cells, respectively. To examine cell migration of GFP-positive cells after organ transplantation, pancreas graft with or without spleen transplantation, heart graft with or without lung transplantation, auxiliary liver and small bowel transplantation were also performed from GFP transgenic rat to LEW (RT11) rats under a 2-week course of 0.64 mg/kg tacrolimus administration. GFP-positive donor cells were detected in the fully allogenic LEW rats after organ transplantation. These results showed that GFP transgenic rat is a useful tool for organ transplantation research such as cell migration study after organ transplantation without donor cell staining. © 2001 Academic Press.