Expression of glucokinase in glucose-unresponsive human fetal pancreatic islet-like cell clusters

Glucokinase (GK) is the glucose sensor in the adult beta-cell, resulting in fuel for insulin synthesis and secretion. Defects in this enzyme in the beta-cell are responsible for the genetic disorder maturity-onset diabetes of the young, with the beta-cell being unable to secrete insulin appropriately when challenged with glucose. The human fetal beta-cell is also unable to secrete insulin when exposed to glucose, but whether GK is present and functional in this developing cell is unknown. To determine the expression of GK in human fetal pancreatic tissue, cytosolic protein was extracted from human fetal islet-like cell clusters (ICCs) at 17-19 weeks gestation and examined for protein content and enzyme activity. On Western blots, a single band corresponding to GK was seen at 52 kDa, and this was similar to that obtained from human adult islets. The maximal velocity (Vmax) of GK was less in fetal ICCs than that in adult islets (8.7 vs. 20.7 nmol/mg protein x h); similar K(m) values were found in both ICCs and islets. No attempt was made to determine which cells in an ICC contained GK. Glucose utilization was determined radiometrically; the Vmax of the high K(m) component was less in ICCs than in islets (31.3 pmol/ICC x h vs. 101.4 pmol/islet.h). Culture of ICCs for 3-7 days in medium containing 11.2 mmol/L glucose resulted in a 3.7-fold increase in the Vmax of GK and a 1.8-fold increase in glucose utilization. These enhanced activities of glucose phosphorylation and glycolysis, however, did not lead to the beta-cell being able to secrete insulin when exposed to glucose. In conclusion, glucokinase is present and functional in human fetal ICCs, but the inability of the human fetal beta-cell to secrete insulin in response to an acute glucose challenge is not due to immaturity of this enzyme.     

Porcine islet xenotransplantation utilizing a vascularized bioartificial pancreas

Successful pancreas/islet transplantation restores normal glucose metabolism in patients with insulin dependent diabetes mellitus (IDDM) but requires chronic immunosuppression which is associated with morbidity and mortality. Immune exclusion devices containing pancreatic islets (bioartificial pancreas) are designed to provide glycemic control without immunosuppression. The immune exclusion is achieved by separating islets from the host by semipermeable membranes. Small molecules such as glucose, insulin and nutrients pass through, whereas immune lymphocytes and immunoglobulins are excluded by the membrane and unable to cause destruction of the islets. Use of xenogeneic islets (i.e., porcine islets) in the device also circumvents the shortage of human donor organs. This report provides a brief summary of our experience with vascularized bioartificial pancreas (VBAP) containing allogeneic and xenogeneic islets for treatment of experimental diabetes in dogs and describes our plans for a clinical trial of the VBAP in patients with IDDM.     

Protein deficiency and nutritional recovery modulate insulin secretion and the early steps of insulin action in rats

Maternal malnutrition was shown to affect early growth and leads to permanent alterations in insulin secretion and sensitivity of offspring. In addition, epidemiological studies showed an association between low birth weight and glucose intolerance in adult life. To understand these interactions better, we investigated the insulin secretion by isolated islets and the early events related to insulin action in the hind-limb muscle of adult rats fed a diet of 17% protein (control) or 6% protein [low (LP) protein] during fetal life, suckling and after weaning, and in rats receiving 6% protein during fetal life and suckling followed by a 17% protein diet after weaning (recovered). The basal and maximal insulin secretion by islets from rats fed LP diet and the basal release by islets from recovered rats were significantly lower than that of control rats. The dose-response curves to glucose of islets from LP and recovered groups were shifted to the right compared to control islets, with the half-maximal response (EC50) occurring at 16.9 +/- 1.3, 12.4 +/- 0.5 and 8.4 +/- 0.1 mmol/L, respectively. The levels of insulin receptor, as well as insulin receptor substrate-1 and phosphorylation and the association between insulin receptor substrate-1 and phosphatidylinositol 3-kinase were greater in rats fed a LP diet than in control rats. In recovered rats, these variables were not significantly different from those of the other two groups. These results suggest that glucose homeostasis is maintained in LP and recovered rats by an increased sensitivity to insulin as a result of alterations in the early steps of the insulin signal transduction pathway.     

Characterization of mixed syngeneic-allogeneic and syngeneic-xenogeneic islet-graft rejections in mice. Evidence of functional impairment of the remaining syngeneic islets in xenograft rejections

Allogeneic mouse islets or xenogeneic rat islets, or fetal porcine islets were implanted under the renal capsule of C57BL/6 mice either alone or carefully mixed with syngeneic islets. With this experimental model the syngeneic islets, although not rejected themselves, are exposed to cytokines and inflammatory mediators released during either allograft or xenograft rejection. No differences in insulin content could be observed between mixed islet grafts and pure syngeneic islet grafts 6 wk after transplantation. Neither was there any morphological evidence of a non-specific destruction of syngeneic islets. These findings suggest that the mechanisms of both allograft and xenograft rejections are highly specific. The hormone release from the mixed syngeneic-allogeneic grafts was similar to that from pure syngeneic islet grafts. In contrast, a pronounced impairment of both the first and second phases of insulin release was observed 2 wk after implantation in mixed syngeneic-xenogeneic islet grafts. When perfusing the mixed islet graft after completed rejection of the concordant xenogeneic rat islets (6 wk after implantation), the insulin release from the remaining syngeneic mouse islets was identical to that of control grafts. However, syngeneic mouse islets exposed to the rejection mechanism of the discordant xenogenic pig islet-like cell clusters did not attain a complete functional recovery.     

Idiopathic capillary leak syndrome complicated by massive rhabdomyolysis

A growing body of evidence suggests that prolactin (PRL) is a potent regulator of the structure and function of the islets of Langerhans, but PRL is a polymorphic hormone that exists in several molecular forms. Therefore, it is important to know whether glycosylated PRL, a major structural variant of the hormone in several species, has an effect different from that of the nonglycosylated PRL on islet function. This in vitro study examined the differential effects of glycosylated and nonglycosylated porcine PRL on cell division and insulin secretion from neonatal rat islets, and compared these results with those produced by homologous rat PRL. The nonglycosylated porcine PRL produced modest stimulation of cell division and insulin secretion from rat islets, but glycosylated porcine PRL had no significant effects. The stimulations produced by nonglycosylated porcine PRL were much weaker in comparison to those produced by the homologous rat PRL. The results show differential effects of the two structural variants of porcine PRL on rat islet function. Although these findings must be confirmed in a homologous system, the results present the possibility that the structural form of the PRL molecule available to the islet tissue may be crucial for its normal functioning.     

Pig islet xenografts are susceptible to "anti-pig" but not Gal alpha(1,3)Gal antibody plus complement in Gal o/o mice

Hyperacute rejection due to Galalpha(1,3)Gal (Gal) Ab plus complement (C') is a major problem in xenografting vascularized organs from pigs to primates, but the fate of neovascularized xeno islets is unclear. Nonendocrine islet cells are Gal+, and there is a large rise in Gal Abs after transplantation, but graft remnants persist for some days in monkeys and humans. To define the role of alphaGal Ab plus C' in porcine islet graft rejection, cultured porcine fetal islets were grafted to mice lacking the alpha(1,3)galactosyltransferase gene. Anti-Gal Ab plus C' did not cause islet damage or rejection in mice lacking the alpha(1,3)galactosyltransferase gene, even when additional Ab plus C' was given; in addition, hyperimmune mice (titer >1/ 20,000) did not reject pig islets, showing that islets are resistant to Gal Ab plus C'. However, islets can be destroyed by polyclonal mouse anti-pig Abs. Thus, the focus of islet xenografting should not be on Gal Ab plus C'.     

Expression of Gal alpha(1,3)gal on neonatal porcine islet beta-cells and susceptibility to human antibody/complement lysis

Neonatal porcine pancreases may be a potential source of islets for transplantation into patients with type 1 diabetes; however, whether these cellular grafts will be susceptible to damage by human natural antibody-mediated rejection remains controversial. Although we and others have demonstrated that porcine islets bind human IgG and IgM, it remains unknown if they express the xenoreactive antigen Gal alpha(1,3)Gal beta(1,4)GlcNAc-R (Gal epitope). In this study, by using the Gal-specific lectin IB4 for immunohistochemistry and fluorescence-activated cell sorter (FACS) analysis, we determined which cell types present in porcine neonatal islet cell (NIC) aggregates express the Gal epitope and which ones are susceptible to lysis by activation of the human complement. After FACS analysis, 30.0 +/- 3.0% of porcine NICs were shown to express Gal, whereas 70.0 +/- 2.0% did not. Histological assessment of Gal-expressing cells revealed that 54.9 +/- 8.8% stained positive for either insulin or glucagon. In contrast, 68.8 +/- 8.4% of the Gal-negative population stained positive for the pancreatic hormones insulin and glucagon. Incubation of either the Gal-positive or -negative cells with human AB serum plus complement for 1.5 h resulted in the lysis of >90% of the cells. These results demonstrate that porcine NIC aggregates are composed of Gal-expressing cells and that expression of Gal is not restricted to nonendocrine cells. Furthermore, both Gal-positive and Gal-negative cells are susceptible to human antibody/complement-mediated cytolysis, suggesting that this form of immunological destruction is an obstacle that will need to be overcome before porcine NIC aggregates can be used clinically.     

Long-term function (6 years) of islet allografts in type 1 diabetes

Eight type 1 diabetic patients, ages 29-41 years, with mean diabetes duration of 23 years (range 18-29 years) received islet transplants from 1 to 5 donors. Seven patients had stable kidney allografts 1-11 years before the islet transplant, and one patient had a simultaneous islet-kidney allograft. Patients' blood glucose control was poor as reflected by the mean +/- SD HbA1c of 9.1 +/- 1.7% before transplant. Of the first three patients, two (1 and 3) achieved insulin independence for 36 and 38 days, respectively. Two recipients rejected their islet grafts within 1 month (2 and 8) and therefore were excluded from analysis. The HbA1c and insulin requirement of the six remaining patients who had persistent islet function for more than 60 days was significantly reduced from 9.3 +/- 1.9 to 6.4 +/- 1.0% (P = 0.002) and from 0.75 +/- 0.15 to 0.35 +/- 0.12 U x kg(-1) x day(-1) (P < 0.001), respectively. The two patients with the longest graft survival (4 and 6) achieved a normalization or near-normalization of their HbA1c levels during 6 years in the absence of severe episodes of hypoglycemia. As demonstrated by a decline in C-peptide response during Sustacal challenge tests over a 6-year period, there was a diminution of islet allograft function over time, despite persistence of normal or near normal HbA1c. We concluded that transplantation of allogeneic islets with an islet mass comparable with whole or segmental pancreas transplants in type 1 diabetic patients can result in long-term islet allograft function; further, we concluded that, in conjunction with small dosages of exogenous insulin, a functioning islet allograft can result in near-normalization of blood glucose levels and significant improvement in HbA1c. The occurrence of severe hypoglycemic episodes observed for patients in the Diabetes Control and Complications Trial was not observed in recipients with functioning islet transplants, despite the continuous need for exogenous insulin therapy to sustain normal HbA1c over the 6-year follow-up. The significant improvement in metabolic control observed for the patients described in this study, and the potential to significantly decrease or halt the progression of diabetic complications, support the continued application of islet allotransplantation as a treatment modality for type 1 diabetic patients.     

Adenovirus-mediated catalase gene transfer reduces oxidant stress in human, porcine and rat pancreatic islets

Susceptibility of pancreatic islets to oxidant stress may affect islet viability and contribute to primary non function of allo- or xenogenic grafts. We investigated the influence of overexpression of catalase (CAT) on the viability of human, porcine and rat islets, as well as INS-1 beta-cell line. Islets were transfected with a replication-deficient adenovirus vector containing human CAT cDNA under the control of the adenovirus major late promoter (AdCAT) or a vector containing no foreign gene (AdNull) and used as a control. Oxidant stress was induced 48 h later by xanthine oxidase-hypoxanthine (XO 25 mU/ml, HX 0.5 mmol/l) or hydrogen peroxide (100 or 250 micromol/l). Islet cell viability was assessed 72 h after CAT transfer by 4-[3-(4-Idophenyl)-2-(4 nitrophenyl)-2H-5-tetrazolio]-1,2,benzene disulphonate (WST-1) test. Baseline catalase activity was three to fourfold lower in porcine than in human islets. CAT activity was reproducibly increased 2.5- to 7-fold in AdCAT infected islets, at least for 13 days. Overall, AdCAT conferred on human and pig islets a protection of 26.1 +/- 6.1 and 21.2 +/- 9.8% on XOHX injury and 35.4 +/- 4.2 and 57.9 +/- 10.5% on H2O2 stress. Similarly, rat islet cells and INS-1 cells were protected on XOHX stress by 17.8 +/- 2.3 and 30.8 +/- 8.7%, respectively. AdNull had no effect. Basal and stimulated insulin secretion was preserved in AdCAT-transfected human islets despite a XOHX challenge. This study validates adenovirus-mediated catalase gene transfer as a realistic approach to reduce non specific inflammation effects on human or porcine islet grafts. Moreover the relevance of defense mechanisms, previously suggested in human islets, is here illustrated in porcine islets.     

Respiratory muscle involvement in Bethlem myopathy

BACKGROUND: There is a great need to learn more about porcine islet physiology because porcine islets represent a promising source of xenogeneic tissue for beta-cell replacement therapy in humans. METHODS: We evaluated the effects of two important physiological regulators of insulin secretion, glucagon-like peptide-1 (GLP-1) and pituitary adenylate cyclase-activating peptide (PACAP), on insulin release and intracellular calcium ([Ca++]i) by adult porcine islet cells. RESULTS: Exposure to GLP-1 and PACAP significantly potentiated glucose-induced insulin release and improved the sensitivity to glucose as a secretagogue. About 70% of cells stimulated with 20 mmol/L glucose alone showed an increase in [Ca++]i, whereas the addition of GLP-1 and PACAP induced [Ca++]i increases in 86% and 93% of cells, respectively. CONCLUSIONS: The good insulin and [Ca++]i responsiveness of porcine islet cells to both GLP-1 and PACAP provides an additional proof of their suitability for transplantation.     

Isolation of islands of Langerhans from human and porcine pancreas for transplantation to humans

The enormous variability of donor factors and organ procurement related variables prevent a constant isolation success, thus reducing the potential number of clinical islet transplants. Since the availability of intact and viable pancreatic donor tissue intended for islet transplantation is limited, the porcine pancreas was selected as a potential source of xenogeneic islets for human recipients. The differences of islet histomorphology between porcine and human pancreas result in a higher intrinsic fragility of porcine islets during collagenase digestion. Nevertheless, if the isolation method is modified to inhibit factors potentially toxic to pig islets, reproducibility of isolation success is higher in the pig as in the human due to a lower variability in donor characteristics and the opportunity of preselection in regard to age and race. If xenograft rejection can be overcome and the risk of xenosis can be minimized, the logistic prerequisites for xenotransplantation of large amounts of viable pig islets into human recipients with insulin dependent diabetes are fulfilled.     

Transcriptional analysis of Marek''s disease virus (MDV) genes in MDV-transformed lymphoblastoid cell lines without MDV-activated cells

Prevention of the occurrence of diabetes-specific vascular complications is the final aim of clinical islet transplantation. Pancreatic islets isolated from adult pigs may be a suitable tissue source to transplant a large number of type 1 diabetic patients. Acute cellular rejection may be finally overcome by clinically applicable protocols for tolerance induction. However, primary nonfunction of the graft, as regularly observed in the porcine islet-to-rat xenotransplantation model, may be an additional problem. In this paper, species-specific inflammatory and immunological mechanisms are discussed which prevent early porcine islet graft function in rats but not in mice.     

Albuminuria after fetal pancreatic islet transplantation: a 10-year follow-up

AIM OF THE STUDY: The prevention of diabetic nephropathy is as yet an unresolved issue. The aim of our study was to assess the effects of transplantation of long-term cultured and cryopreserved fetal pancreas islets on metabolic control and the development of diabetic nephropathy. METHODS: Serum C-peptide, glucose, HbA1c, insulin requirements, urinary albumin excretion rate, and blood pressure of 10 insulin-dependent diabetic patients after transplantation were compared with a group of 27 insulin-dependent diabetic controls on insulin therapy only during a 10-year follow-up. RESULTS: In the first year after transplantation mean insulin requirement decreased from 53.6+/-2.2 to 35.8+/-1.2 units. C-peptide levels appeared (0.55+/-0.08 ng/ml) and remained detectable throughout the follow-up. Blood glucose and HbA1c were significantly (P<0.05) lower than in the controls. Mean albumin excretion rates of the transplant and the control groups during the follow up were 18.8+/-8.5 and 11.7+/-2.0, 16.6+/-6.6 and 14.0+/-2.3, 15.0+/-5.0 and 15.1+/-2.7, 15.3+/-7.5 and 20.4+/-4.2, 19.8+/-6.2 and 36.7+/-11.1, 11.7+/-3.6 and 51.3+/-14.6, 14.1+/-4.2 and 71.4+/-23.1, 22.7+/-8.6 and 92.0+/-28.1, 18.0+/-5.9 and 107.6+/-35.6, 21.7+/-11.0 and 101.5+/-29.3 microg/min respectively. From the 6th year the difference between the two groups was significant (P<0.001). In the transplant group initial mean systolic and diastolic blood pressure values were 132.0+/-3.3 and 81.5+/-1.5 mmHg, in the controls 130.4+/-3.4 and 79.6+/-1.6 mmHg respectively. Significant changes (P<0.05) of blood pressure during the follow-up or differences between the two groups were not observed. CONCLUSIONS: We conclude that fetal islet transplantation is effective in achieving good long-term diabetes control and in the prevention of diabetic nephropathy.     

Xenograft rejection of porcine islet-like cell clusters in immunoglobulin- or Fc-receptor gamma-deficient mice

The aim of the present study was to evaluate the role of xenoreactive antibodies in islet-like cell cluster (ICC) xenograft rejection. For this purpose, normal mice, mice with a targeted disruption of the Fc-receptor (FcR) gamma-chain, or the membrane exon of the immunoglobulin mu-chain gene, were transplanted with fetal porcine ICC under the kidney capsule. Mice lacking the FcR gamma have no functional FcR for IgG or IgE. Mice with disruption of the immunoglobulin mu-chain cannot produce antibodies, because B cell development is arrested at the stage of preB cells. All animals, irrespective of recipient group, readily rejected the ICC xenograft. Analyses of the pattern of cellular infiltration revealed only minor dissimilarities between the different experimental groups. Xenograft destruction was evident on day 6 after transplantation, and a large number of mononuclear cells were found to be evenly distributed throughout the ICC graft. The majority of the infiltrating cells were large, macrophage-like cells expressing the macrophage-specific phenotype marker F4/80. CD3-positive T lymphocytes were found to be mainly accumulated in the peripheral parts of the ICC xenograft. This study has demonstrated that xenoreactive antibodies are not crucial to ICC xenograft rejection in the pig-to-mouse model.     

Interaction of human retinal RGS with G-protein alpha-subunits

The effects of leptin on insulin secretion from pancreatic islets of Sprague-Dawley rats were examined in vitro. In a basal glucose medium (5.5 mM), insulin secretion from isolated islets was significantly decreased after addition of a recombinant leptin (80 nM) (3.20+/-0.14 nmol/10 islets/h) compared with that before the addition (4.41+/-0.30 nmol/10 islets/h). Although significant leptin suppression of insulin secretion was not observed under a glucose-stimulated (11.1 mM) condition, these results suggest that a negative feedback system may exist between leptin and insulin, which increases the production of leptin from adipose tissues.     

Leptin constrains acetylcholine-induced insulin secretion from pancreatic islets of ob/ob mice

Hypersecretion of insulin from the pancreas is among the earliest detectable metabolic alterations in some genetically obese animals including the ob/ob mouse and in some obesity-prone humans. Since the primary cause of obesity in the ob/ob mouse is a lack of leptin due to a mutation in the ob gene, we tested the hypothesis that leptin targets a regulatory pathway in pancreatic islets to prevent hypersecretion of insulin. Insulin secretion is regulated by changes in blood glucose, as well as by peptides from the gastrointestinal tract and neurotransmitters that activate the pancreatic islet adenylyl cyclase (e.g., glucagon-like peptide-1) and phospholipase C (PLC) (e.g., acetylcholine) signaling pathways to further potentiate glucose-induced insulin secretion. Effects of leptin on each of these regulatory pathways were thus examined. Leptin did not influence glucose or glucagon-like peptide-1-induced insulin secretion from islets of either ob/ob or lean mice, consistent with earlier findings that these regulatory pathways do not contribute to the early-onset hypersecretion of insulin from islets of ob/ob mice. However, leptin did constrain the enhanced PLC- mediated insulin secretion characteristic of islets from ob/ob mice, without influencing release from islets of lean mice. A specific enhancement in PLC-mediated insulin secretion is the earliest reported developmental alteration in insulin secretion from islets of ob/ob mice, and thus a logical target for leptin action. This action of leptin on PLC-mediated insulin secretion was dose-dependent, rapid-onset (i.e., within 3 min), and reversible. Leptin was equally effective in constraining the enhanced insulin release from islets of ob/ob mice caused by protein kinase C (PKC) activation, a downstream mediator of the PLC signal pathway. One function of leptin in control of body composition is thus to target a PKC-regulated component of the PLC-PKC signaling system within islets to prevent hypersecretion of insulin.     

Direct evidence that FK506 inhibition of FcepsilonRI-mediated exocytosis from RBL mast cells involves calcineurin

The development of human endocrine pancreas has been the subject of many immunohistochemical studies but very little is known at the molecular level. We have determined the patterns of gene expression of glucagon, somatostatin and pancreatic polypeptide during fetal life (16-41 weeks of gestation) using the dot-blot hybridization method. In spite of some dispersion in the mRNA levels, no progressive increase or decrease during this period of fetal life could be found, as previously observed for insulin. In keeping with these molecular data, no increase in immunostaining of the four hormones was observed, but a dispersion of endocrine cells within the exocrine tissue was noticed at 20 weeks of gestation followed by a clear differentiation of the Langerhans islets at 31 weeks. Interestingly, the mRNA levels of the four hormones were always higher in the fetal pancreas than in the adult pancreas.     

Normalization of diabetes in spontaneously diabetic cynomologus monkeys by xenografts of microencapsulated porcine islets without immunosuppression

Porcine pancreatic islets were microencapsulated in alginate-polylysine-alginate capsules and transplanted intraperitoneally into nine spontaneously diabetic monkeys. After one, two, or three transplants of 3-7 x 10(4) islets per recipient, seven of the monkeys became insulin independent for periods ranging from 120 to 804 d with fasting blood glucose levels in the normoglycemic range. Glucose clearance rates in the transplant recipients were significantly higher than before the graft administration and the insulin secretion during glucose tolerance tests was significantly higher compared with pretransplant tests. Porcine C-peptide was detected in all transplant recipients throughout their period of normoglycemia while none was found before the graft administration. Hemoglobin A1C levels dropped significantly within 2 mo after transplantation. While ketones were detected in the urine of all recipients before the graft administration, all experimental animals became ketone free 2 wk after transplantation. Capsules recovered from two recipients 3 mo after the restoration of normoglycemia were found physically intact with enclosed islets clearly visible. The capsules were free of cellular overgrowth. Examination of internal organs of two of the animals involved in our transplantation studies for the duration of 2 yr revealed no untoward effect of the extended presence of the microcapsules.     

Isolation of the pig islets of Langerhans: evaluation of in vitro and in vivo function

Pig islets are considered the best alternative to human islets in the treatment of insulin-dependent diabetes. Pigs could represent a potential islet donor for xenotransplantation in humans because of the close similarity between human and porcine insulin and the theoretically unlimited availability of porcine pancreas. From November 1991 to January 1997 we performed 221 pig islet isolations from 3 pig sources: group 1: minipigs (age 9-18 months) and white pigs (3-8 months), group 2: large white pigs (5-8 months), group 3: large white pigs (12-24 months). Islets were isolated according to a semi-automated method using enzymatic digestion and purification through discontinuous Euro-Ficoll gradients. The pancreases were surgically removed in our laboratory for group 1, while pancreases from groups 2 and 3 were removed at the slaughterhouse with an average warm ischemia time of 15 minutes. In vitro islet function was assessed by static incubations and perifusions, and in vivo islet function by transplantation under the kidney capsule of nude diabetic mice. The results were as follows: [table: see text] Insulin secretion increased twofold after in vitro glucose stimulation. We obtained restoration of euglycemia in diabetic mice which survived > 3 months after the graft and returned to diabetes after nephrectomy. This study shows that our isolated pig islets are viable and functional in vitro and in vivo after transplantation.     

Pancreas and islet transplantations

Pancreas transplantation has been established as a treatment option for type I diabetes mellitus with one-year patients survival rate of 91% and one-year graft survival rate of 71%. Simultaneous pancreas and kidney transplantation with the bladder-drainage technique is most frequently performed. The bladder drainage technique makes amylase activity measurement in the urine as well as urine cytology possible, which facilitate a diagnosis of acute rejection. Combination treatment with cyclosporine, azatioprine, steroid and anti-lymphocyte globulin is usually employed for immunosuppression. In addition, FK506 in now available and expected to contribute to better graft survival. In contrast, islet transplantation has not yet achieved satisfactory results. Although a large number of islets can now be obtained from one pancreas, they are not sufficient for stabilizing a diabetic condition and multiple donors are still required. Xeno-transplantation may resolve the problem. Both pancreas and islet transplantation will achieve better results with further advance of transplant techniques including immunosuppressive treatment and diagnostic methods for acute rejection.