Carl-Gustav Groth

Clinical improvement and amyloid regression after liver transplantation in hereditary transthyretin amyloidosis

Familial amyloid polyneuropathy (FAP) is a fatal autosomal dominant disorder. Progressive peripheral and autonomic neuropathy are associated with neural and visceral deposition of amyloid, derived most commonly from the Met-30 variant of the plasma protein transthyretin. We have reported previously that orthotopic liver transplantation causes prompt replacement of variant transthyretin by the donor wild-type in the plasma. We now report clinical outcome 1-2 years after transplantation. Three of the first four patients have improved general wellbeing, walking ability, and bowel function, and one of them has regained normal bladder and bowel function. There has been little objective improvement in peripheral neuropathy. The fourth patient, who had the most severe neurological deficits and a complicated postoperative course, has not improved but there has been no further deterioration in contrast to the inexorable progression before transplantation. Quantitative scintigraphy with radiolabelled serum amyloid P component showed visceral amyloid deposits in all three patients studied; in two who were followed serially the deposits regressed after transplantation in association with the clinical improvement. Another FAP patient who was also monitored prospectively for 2 years but who did not undergo transplantation, showed, as expected, progression of neuropathy and increased visceral amyloid deposition. Liver transplantation does therefore have important benefits in FAP during the first 2 years after surgery. Neurological decline is halted and amyloid deposits can be mobilised. The best timing and long-term results of the procedure must now be established.

Biochemical effect of liver transplantation in two Swedish patients with familial amyloidotic polyneuropathy (FAP-met30).

Familial amyloidotic polyneuropathy (FAP) is an autosomal dominant inherited disorder characterized by progressive peripheral and autonomic neuropathy, associated with neural and systemic amyloid deposits. The amyloid fibrils contain a variant transthyretin (TTR) molecule (TTR met30), over 90% of which is produced in the liver. After liver transplantation in two patients with severe symptomatic FAP, only normal TTR was detectable in circulation. The two patients are being monitored at regular intervals, and, although in one patient there was no evidence of reduction in the quantity of amyloid present at 6 months, there had been no further progression of the neuropathy.

Improved survival in patients with insulin-dependent diabetes mellitus and end-stage diabetic nephropathy 10 years after combined pancreas and kidney transplantation.

BACKGROUND The purpose of pancreatic transplantation in insulin-dependent diabetic patients is to restore normoglycemia and thereby prevent the secondary complications of diabetes. However, uncertainty remains as to whether the mortality rate in diabetic patients can be affected by this procedure. METHOD We followed 14 patients with insulin-dependent diabetes mellitus (IDDM) and end-stage diabetic nephropathy for 10 years after successful combined kidney and pancreas transplantation. Fifteen diabetic patients subjected to kidney transplantation alone have served as controls. The glycemic control has been studied annually for 10 years and diabetic polyneuropathy has been assessed in both groups after 2, 4, and 8 years. RESULTS In recipients of pancreas-kidney grafts, metabolic control was maintained throughout the observation period, with values of glycated hemoglobin in the normal range. In contrast, glucose metabolism was impaired in the control group, with glycated hemoglobin values around 10%. Nerve conduction and parasympathetic autonomic dysfunction improved in both groups after 2 years; there was no difference between the groups. After 4 years, we found a significant difference between the study group and the control group, and after 8 years it had widened. At the 4-year evaluation, there was no difference in mortality between the groups. At 8 years, however, a significant difference was noted, which was further substantiated at 10 years with a 20% mortality rate in the pancreas-kidney group versus an 80% mortality in the kidney alone group. CONCLUSIONS We found a substantial reduction in mortality in IDDM patients 10 years after successful combined pancreas and kidney transplantation. We speculate that the decrease in mortality was due to the beneficial effect of long-term normoglycemia on diabetic late complications and suggest therefore that combined pancreas and kidney transplantation, rather than kidney transplantation alone, should be offered to IDDM patients with end-stage diabetic nephropathy.

Isolated human islets trigger an instant blood mediated inflammatory reaction: Implications for intraportal islet transplantation as a treatment for patients with type 1 diabetes

Abstract Islet transplantation offers a logical means to treat insulin-dependent diabetes. However, for reasons poorly understood, the clinical results with islet transplantation have been vastly inferior to those obtained with whole organ pancreas transplantation. The conventional technique for transplanting isolated islets is by intraportal injection, with the islets being trapped in the liver. Human islets exposed to human blood trigged an “instant blood mediated inflammatory reaction”, IBMIR, characterised by platelet consumption, and activation of the coagulation and complement systems. The islets became surrounded by clots and infiltrated with leukocytes, and there was evidence of islet damage as reflected in insulin dumping. When heparin and a complement inhibitor (SCR1), was added to the system, IBMIR was suppressed and islet damage reduced. After intraportal pig-to-pig islet intraportal allotransplantation similar morphological changes was found, corroborating the in vitro findings. Thus, IBMIR inflicts a significant damage to human islets exposed to human blood and IBMIR will also, most likely, enhance the subsequent specific, cell mediated, rejection. Platelet and complement activation seem to be the most important factors in the pathogenesis of IBMIR. The results presented strongly suggest that IBMIR observed both in vitro and in vivo when isolated islets come in contact with blood could provide an explanation for the unsatisfactory results seen in clinical islet allotransplantation.

Damage To Porcine Islets Of Langerhans After Exposure To Human Blood In Vitro, Or After Intraportal Transplantation To Cynomologus Monkeys: Protective Effects of scr1 and Heparin1

BACKGROUND Porcine islets offer an attractive alternative to human islets in clinical islet transplantation. The preferred method of islet transplantation is intra-portal injection into the liver. We have recently shown, both in vitro with human islets and in vivo with porcine islets, that islets exposed to allogeneic blood trigger an injurious inflammatory reaction characterized by activation of both coagulation and the complement systems. We have now tested whether a similar reaction is triggered when xenogeneic porcine islets are exposed to human blood in vitro and after intraportal transplantation into primates. Furthermore, we investigated the effect of inhibiting the complement and coagulation systems. METHOD Islets isolated from adult and fetal porcine pancreas were perfused with fresh human blood in surface heparinized PVC tubings for 5-60 min. Blood cell counts and parameters related to coagulation and the complement system were analyzed, and islets were retrieved after the perifusion was examined by immunohistochemical method. Heparin and soluble complement receptor 1 (sCR1; TP10, 100 microg/ml) were added to the system in some experiments. Furthermore, adult porcine islets were transplanted intraportally into untreated and sCR1- (40 mg/kg BW i.v.) treated cynomolgus monkeys, and plasma insulin concentration was monitored during 60 min after transplantation. RESULTS Porcine islets perifused with human blood triggered an immediate inflammatory reaction, characterized by a rapid consumption and activation of platelets, consumption of neutrophils and monocytes, activation of the coagulation and complement systems, and release of large amounts of insulin. Islet morphologic analysis revealed damaged islets embedded in clots and infiltrated with CD11+ leukocytes. C3a and C5b-9 was deposited on the islet surface, but human immunoglobulin was not. Complement inhibition with sCR1 reduced insulin release significantly. Intraportal islet transplantation into untreated cynomolgus monkeys resulted in a marked and rapid increase in plasma insulin concentration indicative of islet damage. Pretreatment of the monkeys with sCR1 resulted in significantly less insulin release than in untreated control monkeys. CONCLUSION Exposure of isolated xenogeneic islets of Langerhans to blood, both in vitro and in vivo, resulted in acute islet damage. Complement and platelets seem to have a central role in the reactions described. Strategies to efficiently inhibit these reactions will be crucial for clinical intraportal islet xenotransplantation to be successful.

Drug metabolism in human liver in vitro: Establishment of a human liver bank

Marked species differences in xenobiotics metabolism in the liver seriously limit extrapolations from animals to man. Because access to human liver is limited and periodic, we have set up a human “liver bank” available for metabolic studies. The liver tissue is obtained shortly after circulatory arrest from cadaveric (cerebral infarction) kidney transplant donors. Postmortem changes are minimal. Subcellular liver fractions are prepared immediately and part of this is used directly for assay. Intact pieces and subcellular fractions are stored in different media at −80°. Each liver is characterized by light and electron microscopy. Several enzymes, including cytochromes P‐450 and b5, NADPH‐cytochrome c reductase, demethylation of aminopyrine and amitriptyline, epoxidation of carbamazepine, oxidation of acetaminophen, and benzo[a]pyrene, were tested with freshly prepared fractions so that each liver got a “drug metabolic profile.” This “test battery” was repeated after storing to evaluate the effect of storage. Our preparation technique gave a well‐preserved microsomal fraction with minimal contamination. In freshly prepared microsomes the following activities (levels) were observed: cytochrome P‐450, 0.13 to 0.73 nmole/mg protein; NADPH‐cytochrome c reductase, 70 to 426 nmole/mg protein; demethylation of aminopyrine, 0.9 to 4.1, and of amitriptyline, 0.11 to 0.92 nmole/mg protein; carbamazepine‐10,11 epoxidation, 0.03 to 0.46 nmole/mg protein; oxidation of acetaminophen, 0.48 to 2.11, and of benzo[a]pyrene, 0.04 to 0.11 nmole/mg protein · min. These values are generally higher than in the literature. Our storage conditions were efficient: most of the activities were well preserved during storage for at least 6 mo. When pairs of enzyme activities (levels) were plotted against each other with fresh tissue there was good correlation between some but not all activities.

Prevention of Kidney Graft Diabetic Nephropathy by Pancreas Transplantation in Man

Kidney graft biopsies were performed 2–3 yr after transplantation in eight type I (insulin-dependent) diabetic patients who had previously been subjected to kidney transplantation (six patients) or combined kidney and segmental pancreas transplantation (two patients). In five of the six patients that had undergone only kidney transplantation, light microscopic examination of the graft biopsy revealed changes compatible with diabetic nephropathy, and electron microscopic morphometry showed a thickening of the glomerular basement membrane (GBM). In the two patients who had been subjected to combined pancreas and kidney transplantation, the kidney graft biopsy showed no light microscopic changes suggestive of diabetic nephropathy, and electron microscopy showed no thickening of the GBM. Thus, it appears to be possible to prevent the recurrence of diabetic nephropathy in human kidney allografts by simultaneous pancreas transplantation.

Some Characteristics of Steroid Diabetes: A Study in Renal-Transplant Recipients Receiving High-Dose Corticosteroid Therapy

Risk factors and course of steroid diabetes were investigated in 145 renal-transplant recipients who were given a high-dose steroid regimen. Persistent steroid diabetes developed in 25% of the patients and transient diabetes in another 22%. When antidiabetic therapy was required, insulin had to be given in 50%. The incidence of steroid diabetes correlated with steroid dose, age, body weight, and diabetes heredity but not with abnormal glucose tolerance or with another complication of steroid therapy, posterior-pole lenticular cataract. There was no association with HLA-A and B antigens. Thus, steroid diabetes is a frequent complication of high-dose corticosteroid therapy and is similar to type II diabetes. However, it often requires insulin therapy.

Hyperlipidemia in renal transplant recipients treated with sirolimus (rapamycin)

BACKGROUND Sirolimus is an interesting immunosuppressive drug that does not seem to cause nephrotoxicity, neurotoxicity, or diabetogenicity, as commonly seen in patients treated with cyclosporine or tacrolimus. In this report, we describe a possible association between sirolimus and observed hyperlipidemia. METHODS Serum levels of triglycerides and cholesterol were analyzed in 11 patients who participated in a pilot study evaluating the effect of oral sirolimus or placebo combined with cyclosporine and corticosteroids on the occurrence of acute renal transplant rejection. RESULTS In four of nine patients given sirolimus, significantly increased serum triglyceride levels were seen, with peak levels occurring 2-4 months after transplantation and ranging between 11.7 and 42.0 mmol/L (reference value <2.2 mmol/L). In two patients given placebo, the serum triglyceride levels remained below 5.0 mmol/L. After reduction or discontinuation of sirolimus, the serum triglyceride levels decreased within 1-2 months and after 1-8 months levels had returned to their pretransplant values. A significant increase in serum cholesterol levels was seen in one of nine patients given sirolimus. CONCLUSION It seems that long-term treatment with sirolimus in combination with cyclosporine and corticosteroids may increase the risk of hypertriglyceridemia.

Plasma levels of 24S-hydroxycholesterol in patients with neurological diseases.

The brain is the exclusive or almost exclusive site of formation of 24S-hydroxycholesterol and we have shown that the circulating level of 24S-hydroxycholesterol is dependent upon the relation between cerebral production and hepatic clearance. In the present work we determined plasma levels of 24S-hydroxycholesterol in patients with various neurological diseases. Eleven subjects with brain death occurring 6-10 h before collection of the plasma samples had markedly reduced circulating levels of 24S-hydroxycholesterol (-43%, P<0.001). Patients with advanced Alzheimers disease and cerebral inflammatory diseases had slightly lower levels of 24S-hydroxycholesterol in plasma when compared to matched controls. Patients with acute ischemic stroke, multiple sclerosis and primary brain tumors had levels not significantly different from those of controls. The conditions leading to reduced plasma levels of 24S-hydroxycholesterol had no significant effect on plasma levels of another side-chain oxidized oxysterol, 27-hydroxycholesterol. Except for conditions characterized by very marked destruction of the central nervous system, different severe neurological diseases seem to have relatively small effects on the flux of 24S-hydroxycholesterol from the brain.