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Glomerular basement membrane (GBM) thickness was measured in diabetic rats prior to and following islet transplantation. Over the course of the experiment (from 7 to 13 months of diabetes) GBM thickness in diabetic animals exceeded that of littermate controls. After 7 months of diabetes a group of animals received successful intraportal transplants of neonatal pancreatic tissue. GBM thickness at 2 and 6 months following islet transplantation matched the thickness in nontransplanted diabetic rats and exceeded that in control animals. Failure to reverse GBM thickening in diabetic rats following islet transplantation may be due to very slow rates of GBM tunover in the rat. Previous work has demonstrated normalization of urinary albumin excretion after islet transplantation, suggesting that GBM thickening, per se, is not a significant factor causing albuminuria in rats with longstanding diabetes.

Previous studies of the value of percutaneous renal transplant biopsy have been retrospective. We prospectively studied whether biopsy affected patient management. Thirty-five patients with elevated serum creatinine level underwent 44 biopsies in situations in which the diagnosis was in doubt. At the time of biopsy, all clinical and laboratory data were reviewed, and a proposed treatment plan was outlined. Biopsy results were available within 24 hours. We evaluated whether biopsy influenced treatment. Other than hematuria (less than 24 hours), there were no complications. Nine biopsy specimens (20.5%) were inadequate for evaluation. Forty-six percent of adequate biopsy specimens (36% of total biopsy specimens) influenced patient management. Adequate biopsy specimens resulted in a change in treatment in 10 of 19 patients receiving prednisone and azathioprine and 6 of 16 receiving prednisone and cyclosporine. The remaining biopsy specimens, although not changing management confirmed the treatment plan in ambiguous clinical situations. We conclude that percutaneous biopsy is an important aid in patient management.

Herpes simplex virus (HSV) and cytomegalovirus (CMV) infections occur frequently after renal transplantation. To determine the effect of these infections on long-term prognosis, we reviewed the charts of 558 patients who underwent primary renal transplantation between Jan 1, 1974 and Dec 31, 1978, at the University of Minnesota Hospitals, Minneapolis, for cultural evidence of these infections. The presence of HSV alone appeared to have a minimal effect on either patient or allograft survival. Positive CMV cultures were associated with decreased patient and allograft survival. Patients with HSV and CMV infections had further reduced patient and allograft survival. Lethal CMV syndrome and associated severe bacterial and fungal infections were common and frequently were the immediate cause of death in patients who had concomitant positive HSV and CMV cultures. Concurrent HSV and CMV infections in renal transplant patients may be a grave prognostic indicator, being associated with enhanced mortality and renal allograft loss.

Streptozotocin-induced diabetes in the rat can be reversed by the transplantation of isogenic islets of Langerhans from neonatal donors. We studied the morphology of intraportally transplanted islets with the aid of the immunoperoxidase staining technique to identify insulin-, glucagon-, somatostatin-, and pancreatic polypeptide-containing cells at 24 hours, 48 hours, 1 week, 2 weeks, 4 weeks, 39 weeks, and 65 weeks after transplant. Embolized pancreatic tissue, composed of approximately 80% acini and 20% islets, is initially distributed throughout the liver mainly to terminal branches of the portal system. Endothelialization and organization occur rapidly with the smaller fragments and within the first 4 weeks for larger thrombi. Exocrine pancreatic elements largely disappear as islet cells move into the hepatic lobules from the portal spaces. At 65 weeks after transplant, all islet cell types can be identified within large complex islet structures. The results of this study establish the survival and continued function of all known rat pancreatic islet cell types long after transplantation and support the theory that islet transplantation may represent the most physiologic replacement of hormonal deficiencies in the diabetic recipient.

1. There have been 1,426 renal transplants performed at the University of Minnesota from January 1, 1980 through August 31, 1988. CsA+P was used by 260 adult recipients, CsA+P+AZA(+ALG) by 536. 2. In general, there are no significant differences in actuarial graft or patient survival rates between the 2 CsA protocols. This is true for all adults, for all adult CAD recipients, and for a matched control group of adult CAD recipients. 3. Cox's proportional hazards regression model also indicates that there is no significant difference between the 2 CsA regimens. Donor type, number of transplants, and age at transplant influence graft survival in all adult recipients. The use of LRD is still indicated in the CsA era. Diabetic status, age at transplant, and number of transplants affect patient survival. The model fits the observed data quite well. 4. Actuarial analysis and Cox regression failed to document a beneficial effect of HLA-A, B, and DR matching in patients receiving either CsA protocol. Our data do not support the HLA matching point system currently used by UNOS or the Terasaki proposal to give points based on mismatching. 5. A matched control analysis of adult CAD recipients indicates that CsA+P+AZA+ALG has alleviated the problems of our CsA+P protocol without lowering the graft and patient survival rates. Thus, the sequential therapy group has equivalent graft and patient survival rates but shorter duration of ATN, lower serum creatinine levels at 1 year, and fewer patients who require modifications of protocol. Sequential therapy is our treatment of choice.

We compared the efficacy of continuous intraarterial versus intravenous 6-mercaptopurine (6-MP) infusion in a mongrel canine renal allograft model with regard to overall survival, incidence of systemic and renal toxicity, and systemic drug exposure. Arterial anastomoses were done end-to-end, and infusion catheters were placed in the iliac artery or vena cava and connected to a subcutaneously placed programmable pump. A dose of 0.5 mg/kg/day 6-MP did not prolong survival over heparin-treated or untreated controls (MST = 7 days for both groups) when administered either locally or systemically. However, 0.75 mg/kg/day 6-MP i.a. (MST = 20 days) significantly prolonged survival over both untreated (P = 0.007) and heparin-treated controls (P = 0.02), with all dogs eventually dying of rejection. In contrast, 0.75 mg/kg/day i.v. (MST = 7 days) failed to prolong survival over controls (P greater than 0.1) and produced death from systemic toxicity in 3 of 7 animals. Six of 7 dogs receiving 2.0 mg/kg/day 6-MP i.a. (MST = 12 days) developed azotemia secondary to drug-induced nephrotoxicity. Identical renal histologic changes occurred in the same time frame in autotransplants treated similarly. Of 7 animals receiving 2.0 mg/kg/day i.v. (MST = 12 days), 5 died from early, severe systemic drug toxicity and 2 from early rejection. During 6-MP infusion at 0.5 mg/kg/day, systemic exposure was significantly less in the locally treated than in the systemically treated dogs when Cr concentrations were normal or moderately elevated (P less than 0.0005 and P = 0.01, respectively) but not when renal function became severely impaired (P = 0.34). In contrast to i.v. infusion, i.a. 6-MP delivery dissociated immunosuppressive efficacy from systemic toxicity, supporting previous work demonstrating high first-pass renal elimination of 6-MP. We conclude that tightly controlled local delivery of an immunosuppressive agent can effectively prolong graft survival with reduced systemic toxicity in a large animal model employing a pump/catheter system applicable to man.

Forty-nine dogs were made diabetic by total pancreatectomy. Fifteen untreated pancreatectomized animals survived a mean (+/-S.E.) of 7.0 +/- 1.1 days with a mean (+/-S.E.) plasma glucose level of 402 +/- 26 mg/100 ml before death. The pancreata of 32 dogs were distended with cold (4 degrees ) Hanks' solution, minced, digested with collagenase (600 U/ml tissue) for 15-25 minutes, and autotransplanted either into the splenic artery (three dogs), directly into the splenic pulp (21 dogs), or into the portal vein (ten dogs). Tissue infusion into the splenic artery resulted in infarction and persistent hyperglycemia. Direct implantation into the splenic pulp of tissue digested for 15, 20 and 25 minutes resulted in permanent normoglycemia (fasting plasma glucose < 150 mg/100 ml) in 7 of 8, 7 of 7, and 6 of 6 dogs respectively. Glucose tolerance test mean (+/-S.E.) K values (% decline of plasma glucose concentration/minute) in these groups two weeks after transplantation were 1.20 +/- 0.20%, 1.60 +/- 0.25 and 0.70 0.08% respectively, indicating that 20 minutes digestion was best for intrasplenic transplantation. Tissue prepared in the optimal manner (20 minutes digestion) and embolized into the liver resulted in normoglycemia in three of eight dogs, and a mean (+/-S.E.) K value of 0.77 +/- 0.10%. Both dogs receiving tissue dispersed for 25 minutes into the portal vein remained hyperglycemic. In the dogs subjected to intraportal transplantation, portal pressure rose from a mean (+/-S.E.) of 6.5 +/- 0.6 cm H(2)O before to 21.9 +/- 2.2 cm H(2)O immediately after tissue embolization, but declined to 6.5 +/- 1.0 cm H(2)O by ten weeks in animals becoming normoglycemic. We conclude that in dogs direct implantation of pancreatic tissue into the splenic pulp is superior to embolization into the portal vein or splenic artery because the splenic circulation is not compromized, portal hypertension is obviated, and glucose metabolism is best controlled as judged by glucose tolerance test K values.

Twelve pancreases from human infants one year old or less were analyzed for tissue insulin and amylase content before and after dispersal of pancreatic fragments by mincing and collagenase digestion. Tissue insulin and amylase content provide an index of pancreatic islet mass and exocrine digestive enzyme content, respectively. The results were compared with similar anaylses performed on juvenile and adult human pancreases before and after islet isolation and on intact and dispersed neonatal rat and adult rat pancreas. Infant human pancreas has an average tissue insulin concentration of 1,128 mug./gm. of tissue and a total insulin content of 1,718 mug/pancreas, as against values of 140 mug./gm. of tissue and 7,209 mug./pancreas for adult human pancreas. Average tissue amylase concentration is 0.24 mg./gm. of tissue in infant human pancreas and 3.0 mg./gm. of tissue in adult human pancreas. The insulin/amylase ratio in infant pancreas is 4,800, as against 46 in the adult pancreas. Neonatal rat pancreas, which can be dissociated and transplanted without separation of islet and exocrine components, has a similarly high tissue insulin and low tissue amylase content when compared with adult rat pancreases. Infant human pancreas has a total islet mass 24 per cent that of an adult human pancreas, and neonatal rat pancreas has a total islet mass 11 per cent of that of an adult rat pancreas. One neonatal rat pancreas prepared by minimal collagenase digestion can cure diabetes when transplanted via the portal vein to a rat. Following dispersal of infant human pancreas by collagenase digestion, the islet content and the insulin/amylase ratio of the recovered tissue equals or exceeds that which usually can be isolated from adult cadaver pancreases. Infant human pancreas is a rich source of islet tissue that is relatively uncontaminated by exocrine digestive enzymes. After dispersal, infant human pancreas may be ideal for transplantation to selected diabetic patients.

Acute liver failure carries a high rate of mortality, but if metabolic support can be maintained for a critical period, liver healing and recovery are possible. Current techniques of temporary hepatic support are cumbersome and inconsistently effective. We studied the ability of dispersed hepatocytes to provide metabolic support when transplanted to rats with liver failure induced by dimethylnitrosamine (DMNA), a rapidly metabolized agent that is selectively toxic to liver cells. DMNA (20 mg/kg) was administered intravenously to 92 Lewis rats. Animals were divided into four groups receiving the following treatments 24 hours after DMNA administration: group I-intraperitoneal transplantation of hepatocytes prepared from 2.0 gm of normal isologous rat liver; group II-infusion into the portal vein of hepatocytes prepared from 1.5 gm of liver; group III-infusion of saline into the portal vein; group IV-no further treatment. The percentages surviving in each group 3 weeks after DMNA administration were 63%, 71%, 17%, and 6%, respectively. Mean serum glutamic oxaloacetic transaminase (SGOT) levels 3 days after DMNA administration were similar in the four groups, indicating that the degree of liver damage was equivalent. A significantly higher proportion of hepatocyte treated rats survived. Liver histology after DMNA administration showed hemorrhagic central lobular necrosis. A return to near-normal architecture occurred by 3 weeks in surviving animals. In group II hepatocytes were seen in portal venules, sinusoids, and central veins. We conclude that dispersed hepatocytes, transplanted either intraperitoneally or via the portal vein, can provide sufficient metabolic support to allow for recovery from drug-induced hepatic necrosis.

Thirty-one episodes of biopsy-proved acute rejection (R) in 28 patients maintained on cyclosporine did not respond to high-dose steroids and were treated with antilymphocyte globulin (ALG). Cyclosporine was discontinued in all but three during ALG administration. (A) Twenty-four patients received 26 courses of ALG within 90 days of transplant (11 1st R, 15 2nd or 3rd). Seven treatment courses were cut short due to infection (4), ongoing R (2) and a combination of infection and rejection (1). Only 1 of 7 has a functioning graft. Of the remaining 19 full ALG courses (17 patients) (8 1st R, 11 2nd or 3rd), 13 (11 patients) responded (7 1st R, 6 greater than 1st). The remaining 6 patients lost their grafts to ongoing acute rejection. (B) Five patients were treated after 6 months posttransplant; two responded but no grafts currently function. (C) Overall 7 patients developed systemic infection (7 viruses, 1 Candida) with 1 death, and 2 additional patients developed severe thrombocytopenia and leukopenia. Patients responding to their ALG course were restarted on cyclosporine. We conclude that ALG is not as effective in reversing steroid-resistant rejection in patients maintained on cyclosporine as it has been in patients maintained on azathioprine. However, more than 50% of steroid-resistant rejection episodes are reversed.

Allotransplantation provides another strategy for the treatment of metabolic diseases. In disorders which primarily affect a specific tissue or organ, appropriate allografts have already proved therapeutically effective. Most of these diseases presumably result from dominantly inherited structural genetic defects. Metabolic transplantation, the grafting of tissues for the continuous production of the normal gene products, can provide effective treatment in appropriate, inherited, metabolic diseases. However, it must be emphasized that this approach is exploratory, and further studies in experimental model systems must be continued. Future advances in immunology and transplantation biology may increase the potential effectiveness of allotransplantation for the treatment of metabolic diseases.

A sustained decrease of plasma bilirubin concentrations occurred in homozygous recessive Gunn rats lacking the enzyme uridine diphosphate glucuronyltransferase following infusion into the portal vein of hepatocytes from heterozygous nonjaundiced Gunn rats possessing the enzyme. Transplantation of cells capable of continuous enzyme production could be an effective mode of therapy for congenital enzyme deficiency diseases.

We report a case of homozygous adenine phosphoribosyl transferase (APRT) deficiency associated with 2,8-dihydroxyadenine stones recurrent in a patient with a renal transplant. The disease was diagnosed 23 years after the initial episode of renal colic. At that time the disease was unknown. Our patient is only the second case of this disorder reported from the United States. Correct diagnosis is important because long-term maintenance with allopurinol and a low purine diet can effectively prevent stone formation and renal failure.

An increased incidence of malignancy has been reported in transplant recipients. The pathogenesis of this increase was originally attributed to immunosuppressive therapy. However, not all tumours are increased in proportion to their occurrence in the general population-75% of reported tumours are lymphorproliferative or carcinoma of the skin, lip, or cervix. This cannot be explained by impaired immunosurveillance, and alternative hypotheses must be considered. 90% of transplant recipients develop clinical or serological evidence of herpesvirus infection. Herpesviruses have been implicated in the pathogenesis of lymphorproliferative tumours and carcinoma of the skin and cervix. They can remain in latent form and be reactivated by allogeneic stimulation and/or immunosuppression. These viruses localise to skin, cervix, and neural tissue-i.e., exactly those sites where cancer develops in transplant patients. Herpesvirus infections in association with the presence of an allogeneic graft in an immunosuppressed patient may be responsible for the increased incidence of both lymphoproliferative tumours and carcinoma of the skin, lip, and cervix in the transplant recipient.

Routine bilateral nephrectomy and splenectomy (BNS) in uremic patients before transplantation are relatively safe procedures except when there is pre-existing sepsis, diabetes, or severe hypertension. A review of 421 patients undergoing routine pretransplantation BNS reveals that death before transplantation occurs in two definable groups of patients. In our series, the first group, those with juvenile onset diabetes, have a 15.4 per cent pretransplantation mortality (9.6 per cent operative and 5.8 per cent nonoperative) while being maintained on hemodialysis and awaiting transplantation. The second group, nondiabetic patients with other preoperatively definable risk factors such as severe hypertension and infected kidneys, had a 3.25 per cent pretransplantation mortality (1.9 per cent operative and 1.25 per cent nonoperative) while on hemodialysis. Paradoxically, these same factors are used as absolute criteria for pretransplantation nephrectomy at institutions where this operation is not a routine part of the pretransplantation regimen.

By total pancreatectomy 41 dogs were made diabetic. Of these, 15 dogs remained untreated, served as diabetic controls, and died within x = 7 +/- 1 days postoperatively. In the experimental groups the best results were obtained (as judged by K values of iv glucose tolerance test and iv Tolbutamide test curves) after 20 min of incubation with collagenase and immediate transplantation into the splenic pulp. After 15 min and 25 min of incubation, normoglycemia regularly occurred, but in the 20 min collagenase group the K values resembled most closely those of normal dogs. The animals stayed normoglycemic and were observed for up to 6 months. Splenectomy led to reocurrence of the diabetic state and death within 4.8 +/- 1.5 (S.E.) days.

It is not known whether the advantage of the portal vein as a transplant site for islet transplantation is caused by the immediate availability of a blood supply or by the localization of the islets in the portal circulation. We transplanted minimal quantities of islet tissue from neonatal rat donors to isogeneic adult rats with streptozotocin-induced diabetes. Transplants were performed to three sites, i.p., portal vein, and systemic vein (i.v.). When four neonatal donors were used for each recipient there were no i.p. cures but 90% i.v. and 100% portal vein cures, which suggests that access to a blood supply is important. As the amount of tissue transplanted was decreased, there were significantly more cures with the portal vein route, which suggests that localization of the islets in the portal circulation is also important to graft survival.

Eleven selected patients with a history of cancer have received renal transplants. In three patients the malignancies were diagnosed and treated before renal failure developed. Two patients underwent bilateral nephrectomies for the treatment of bilateral renal malignancy. In six patients the malignancy developed while they were uremic, and they received transplants after treatment of the tumor. Recurrent tumor developed in only one of the 11 (9 per cent) patients after receiving the transplant. Thus, patients with a history of malignancy can receive a transplant without accelerating growth of the tumor. We recommend a minimum period of one year between tumor treatment and transplantation to observe for tumor recurrences or metastases. A longer period of observation may be necessary in patients who have tumors with a poorer prognosis.

The immunopathology of five cases of spontaneous allograft rupture has been studied. All kidneys were edematous on exploration and routine histological sections showed interstitial edema and mononuclear cell infiltration characteristic of acute rejection. Immunofluorescence revealed, at most, scattered vascular deposition of IgM and mild mesangial C3 deposition. These findings are compared with findings in normal kidneys and kidneys which had been hyperacutely rejected. The normal kidney showed focal afferent arteriolar and proximal mesangial stalk deposition of C3 without IgM. The kidneys of patients with hyperacute rejection showed brilliant staining for fibrin and IgM in all arterial and arteriolar walls with lesser amounts of C3 and IgG; IgM and C3 were prominent in the glomerulus. These findings suggest that mechanisms other than circulating preformed antibodies are responsible for the pathogenesis of spontaneous allograft rupture.

Antilymphocyte globulin (ALG) has been advocated for the treatment of renal transplant rejection episodes in patients maintained on prednisone and azathioprine. Treatment with steroids (outpatient) is considerably less expensive than with ALG (inpatient), so we studied whether routine ALG was necessary. Between 3/82 and 11/83, 54 cadaver transplant recipients maintained on prednisone and azathioprine who developed a first rejection episode were randomized to receive--for treatment of their first, and if necessary second, rejection--methylprednisolone (MP) plus ALG (n = 24), or MP alone, with ALG added if treatment failed (n = 30). Treatment failure was defined as continuing deterioration on T131 iodohippuran scan, rising serum creatinine level, or lack of improvement within 7 days. There was no significant difference in patient survival, graft survival, mean number of rejections, and infection rate between the two groups: 60% (18/30) of first and 50% (10/10) of second rejection episodes responded to MP alone. We conclude that patients are not penalized by initial rejection treatment with MP. Many rejection episodes respond to steroids alone; elimination of routine ALG use will save hospitalization time and expense.

Minced adult human, rat, and dog pancreatic fragments were cultured under various conditions in an attempt to selectively purify pancreatic islet tissue from exocrine digestive enzymes. Islet purification was assessed by measuring tissue insulin and amylase concentrations, proportional to islet beta cell mass and exocrine enzyme content, respectively. Tissue amylase content decreased rapidly over a 24 hour culture period under all conditions. By addition of pilocarpine, cobalt chloride, and aprotinin to the culture medium, pancreatic tissue insulin levels stabilized. Under these conditions the tissue insulin: amylase ratio increased rapidly and a high ratio was maintained, indicating that islet tissue decontaminated of exocrine digestive enzymes was preserved in short-term culture. Fifteen dogs rendered diabetic with streptozotocin immediately following a partial pancreatectomy received an autotransplant of pancreatic tissue fragments maintained in culture for 24 hours. Seven dogs were rendered normoglycemic. Six of these dogs have survived for longer than 30 days. Only one of 14 control pancreatectomized dogs injected with streptozotocin and not transplanted survived and was normoglycemic. Viable islet tissue free of exocrine enzymes can be obtained by short-term culture of pancreatic fragments, and separation of islet and exocrine components of adult pancreas is not essential for successful islet transplantation.