| 1. |
- Biglarnia, Ali-Reza, et al.
(författare)
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Complement Interception Across Humoral Incompatibility in Solid Organ Transplantation : A Clinical Perspective
- 2015
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Ingår i: IMMUNE RESPONSES TO BIOSURFACES. - Cham : Springer International Publishing. - 9783319186030 - 9783319186023 ; , s. 211-233
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Konferensbidrag (refereegranskat)abstract
- The humoral barrier in transplant biology is the result of preformed donor-specific antibodies (DSAs), directed either against human leukocyte antigens (HLA) or non-HLA antigens such as blood group (ABO) molecules. The term "sensitization" applies to patients carrying these antibodies. Transplantation is widely accepted as a life-saving opportunity for patients with terminal end-organ disease. However, in sensitized patients, transplant outcome is hampered by antibody-mediated rejection (AMR) as a consequence of DSA exposure. Furthermore, sensitized patients have limited access to "matched" organs from the both living and deceased donor pool. Considering the crucial role of the complement system in the pathophysiology of AMR and the availability of complement intervention therapeutics, there is a growing interest in complement-targeting strategies. This review highlights the emerging importance of monitoring and modulation of the complement system in the context of enabling transplantation across humoral incompatibility in sensitized recipients with preformed anti-HLA or natural anti-ABO antibodies. It also discusses the significance of the complement system in the induction of accommodation and further emphasizes current and future perspectives of novel complement therapeutics.
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| 2. |
- Weinreich, Ilse Duus, et al.
(författare)
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Scandiatransplant Exchange Program (STEP) : Development and Results From an International Kidney Exchange Program
- 2023
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Ingår i: Transplantation direct. - : Lippincott Williams & Wilkins. - 2373-8731. ; 9:11
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Tidskriftsartikel (refereegranskat)abstract
- Background. Kidney transplant candidates may be incompatible with their intended living donors because of the presence of antibodies against HLA and/or ABO. To increase the possibility of finding an acceptable kidney donor for these patients, the Scandiatransplant Exchange Program (STEP) program within Scandiatransplant was launched in 2019.Methods. This is a retrospective review of our experiences from the first 4 y of the STEP program, including details about the match runs, performed transplantations, and recipient outcomes within the program.Results. During 2019-2022, 11 match runs and 4 reruns were performed. In total, 114 pairs and 6 anonymous donors participated in these match runs. Fifty-one pairs (45%) participated in 1 match run, 31 pairs (27%) participated in 2 match runs, and 32 pairs (29%) participated in >= 3 match runs. Seventy-two individuals (63%) participated because of HLA incompatibility, 19 (17%) because of ABO incompatibility, and 7 (6%) because of both HLA and ABO incompatibility. Forty percent of the patients enrolled in the program underwent transplantation. In total, 49 transplantations have so far been performed within the program, and 46 (94%) of the recipients had a functioning kidney graft at follow-up in February 2023.Results. During 2019-2022, 11 match runs and 4 reruns were performed. In total, 114 pairs and 6 anonymous donors participated in these match runs. Fifty-one pairs (45%) participated in 1 match run, 31 pairs (27%) participated in 2 match runs, and 32 pairs (29%) participated in >= 3 match runs. Seventy-two individuals (63%) participated because of HLA incompatibility, 19 (17%) because of ABO incompatibility, and 7 (6%) because of both HLA and ABO incompatibility. Forty percent of the patients enrolled in the program underwent transplantation. In total, 49 transplantations have so far been performed within the program, and 46 (94%) of the recipients had a functioning kidney graft at follow-up in February 2023.Conclusions. The STEP program offers sensitized patients an enlarged pool of living donors and a chance of a compatible international living donor, resulting in an increased number of total transplantations. Currently, STEP is one of the largest transnational kidney exchange programs and has improved the situation for patients waiting for kidney transplantation in Scandiatransplant.
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| 3. |
- Berglund, David, et al.
(författare)
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Screening of mortality in transplant patients using an assay for immune function
- 2011
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Ingår i: Transplant Immunology. - : Elsevier BV. - 0966-3274 .- 1878-5492. ; 24:4, s. 246-250
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: So far, the ImmuKnow Immune Cell Function Assay (Cylex, Inc., Columbia, MD, USA) has been used to assess risks of infection and rejection in transplant patients. We hypothesized that the ImmuKnow assay might be used for mortality screening in transplant patients overall. METHODS: In the period of February 2007 to December 2009, at the Uppsala University Hospital, 362 patients who received either kidney, kidney+pancreas, kidney+islet cells, liver or liver+kidney allografts were randomly screened using the ImmuKnow assay. All causes of mortality were compared between two groups: patients with at least one ImmuKnow assay below 175ng/mL and patients with all ImmuKnow assays from 175ng/mL and above. Subsequently, the frequency of rejection within thirty days of the ImmuKnow assay was compared between these two groups. RESULTS: The study included 1031 ImmuKnow assays obtained from the 362 patients. A total of 111 patients had at least one ImmuKnow below 175ng/mL and 251 patients had all their ImmuKnow assays from 175ng/mL and above. By January 31st 2010, 16 of 111 patients (14.4%) with at least one ImmuKnow assay below 175ng/mL were deceased, compared to 13 of 251 patients (5.2%) with all ImmuKnow assays from 175ng/mL and above (p=0.0053, Fisher's exact test). There was no difference in the frequency of rejection between the two groups (19.8% versus 17.5%, p=0.66). CONCLUSIONS: In addition to assessing relative risks of infection and rejection in transplant patients, the ImmuKnow assay may be used to identify patients with increased risk of short-term mortality. Transplant patients being highly overimmunosuppressed as assessed by the ImmuKnow assay do not seem to have a lower risk of short-term rejection.
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| 4. |
- Biglarnia, Alireza, et al.
(författare)
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Decentralized glomerular filtration rate (GFR) estimates in healthy kidney donors show poor correlation and demonstrate the need for improvement in quality and standardization of GFR measurements in Sweden
- 2007
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Ingår i: Scandinavian Journal of Clinical and Laboratory Investigation. - : Informa UK Limited. - 0036-5513 .- 1502-7686. ; 67:2, s. 227-235
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Glomerular filtration rate (GFR) is generally accepted as the best overall index of renal function. Thus, all potential live kidney donors are tested to ensure that they have a normal GFR before they are eligible for kidney transplantation. The choice of GFR test is very much dependent on local traditions and may include iohexol, 51Cr-EDTA, inulin, or creatinine clearance based on urine collection, and creatinine clearance calculated from the Cockcroft-Gault or Modification of Diet in Renal Disease (MDRD) equation as well as cystatin C. The aim of this study was to compare the results of GFR measurements performed in all actual live kidney donors who have undergone live donor nephrectomy at the University Hospital in Uppsala, Sweden, between the years 2000 and 2004. MATERIAL AND METHODS: The patients were selected from all parts of Sweden and the measurements were performed at their local hospital. RESULTS: We found large discrepancies between repeated iohexol measurements in these presumably healthy individuals. There was also a poor correlation between iohexol clearance and calculated creatinine clearance using the Cockcroft-Gault (R2=0.046) or MDRD formula (R2=0.045). CONCLUSIONS: The study shows that the standardization and quality of GFR measurements in Sweden have to be improved.
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| 5. |
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| 6. |
- Biglarnia, Alireza, et al.
(författare)
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The free radical scavenger S-PBN significantly prolongs DSG-mediated graft survival in experimental xenotransplantation
- 2012
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Ingår i: Xenotransplantation. - : Wiley. - 0908-665X .- 1399-3089. ; 19:3, s. 166-176
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Tidskriftsartikel (refereegranskat)abstract
- Background: Nitrones such as 2-sulfo-phenyl-N-tert-butyl nitrone (S-PBN) are known to trap and stabilize free radicals and to reduce inflammation. Recently, S-PBN was shown to reduce infiltration of T lymphocytes and the expression of adhesion molecules on the endothelium in experimental traumatic brain injury. We hypothesized that S-PBN could reduce infiltration of T lymphocytes during cell-mediated xenograft rejection and thereby increase graft survival. The concordant mouse-to-rat heart transplantation model was used to test the hypothesis. In this model, grafts undergo acute humoral xenograft rejection (AHXR) almost invariably on day 3 and succumb to cell-mediated rejection on approximately day 8 if AHXR is inhibited by treatment with 15-deoxyspergualin (DSG). Material and methods: Hearts from Naval Medical Research Institute (NMRI) mice were transplanted to the neck vessels of Lewis rats. Recipients were treated with S-PBN (n = 9), DSG (n = 9), S-PBN and DSG in combination (n = 10) or left untreated (n = 9) for survival studies. S-PBN was given daily intraperitoneally at a dose of 150 mg/kg body weight (BW) on day -1 to 30, and DSG was given daily intraperitoneally at a dose of 10 mg/kg BW on day -1 to 4 and 5 mg/kg BW on day 5 to 21. Nine additional recipients were given S-PBN only on days -1 and 0 in combination with continuous DSG treatment. Grafts were monitored until they stopped beating. Additional recipients were treated with S-PBN (n = 5), DSG (n = 5), S-PBN and DSG in combination (n = 6) or left untreated (n = 5) for morphological, immunohistochemical and flow cytometry analyses on days 2 and 6 after transplantation. Results: S-PBN treatment in combination with DSG resulted in increased median graft survival compared to DSG treatment alone (14 vs. 7 days; P = 0.019). Lower number of T lymphocytes on day 6 (P = 0.019) was observed by ex vivo propagation and flow cytometry when combining S-PBN with DSG, whereas immunohistochemical analyses demonstrated a significant reduction in the number of infiltrated CD4+, but not TCR+, cells. S-PBN treatment alone had no impact on graft survival compared to untreated rats (3 vs. 3 days). No differences were seen in ICAM-1 and VCAM-1 expression or in morphology between the groups. Conclusion: The combination of S-PBN and DSG treatment increases xenograft survival. The main effect of S-PBN appears to be in direct connection with the transplantation. Because of its low toxicity, S-PBN could become useful in combination with other immunosuppressants to reduce cell-mediated xenograft rejection.
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| 7. |
- Biglarnia, Alireza, et al.
(författare)
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Venous thromboembolism in live kidney donors : a prospective study
- 2008
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Ingår i: Transplantation. - 0041-1337 .- 1534-6080. ; 86:5, s. 659-661
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Tidskriftsartikel (refereegranskat)abstract
- AIM:The aim of this study was to evaluate risk factors for venous thromboembolism (VTE) and deep vein thrombosis after living donor nephrectomy in a center using extensive preoperative screening and perioperative venous duplex scan.MATERIAL AND METHODS: Thrombophilia screening and pre- and postoperative ultrasonographies were performed in 130 consecutive living kidney donors (laparoscopic 105, open 25). Donors were followed prospectively for at least 3 months. All donors received prophylaxis with the low molecular weight heparin enoxaparin and compression stockings. Donors with increased risk received a double dose of enoxaparin and the prophylaxis was continued for 6 weeks. Donors with venous thrombosis at discharge duplex also received prolonged prophylaxis.RESULTS:The frequency of thrombophilia was similar to what can be expected in the Swedish population (four with factor V Leiden and one each with protein S deficiency, prothrombin gene mutation, and anticardiolipin antibodies). Preoperative duplex was normal. Three donors had small postoperative deep vein thrombosis. Twelve donors (9.2%) received an intensified and prolonged prophylaxis. No further thromboembolic complications developed in 3 postoperative months.CONCLUSION:With the present protocol for preoperative evaluation, perioperative duplex screening, and prophylaxis, the risk of postoperative VTE is low after living donor nephrectomy. Given that 9.2% had risk factors or developed deep vein thrombosis, the extraordinary situation of an operation being performed on a healthy person who has no therapeutic benefit and the low incidence of VTE in the present study, we recommend the presented approach to be implemented more broadly and that further studies are performed in larger cohorts.
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| 8. |
- Bockhorn, Maximilian, et al.
(författare)
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VEGF is important for early liver regeneration after partial hepatectomy
- 2007
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Ingår i: Journal of Surgical Research. - : Elsevier BV. - 0022-4804 .- 1095-8673. ; 138:2, s. 291-299
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND:The aim of the study was to determine the role of Vascular Endothelial Growth Factor (VEGF) on the microvasculature and on angiogenetic gene expression after partial hepatectomy (PH) in the rat model.METHODS: To determine the effect of exogenous and endogenous VEGF after PH, rats were subjected to 70% PH and treated either with VEGF, anti-VEGF or NaCl. Postoperatively (3-168 h), vessel density (VD), vessel diameter (VDi), and intersinusoidal space, liver body weight ratio (LBR), hepatic proliferation and biochemical markers were assessed. To further elucidate the underlying molecular mechanisms hepatic gene expression was determined by customized cDNA arrays and quantitative RT-PCR.RESULTS:In the VEGF group, VD, VDi, and LBR were significantly increased compared with anti-VEGF or controls. Blockage of endogenous VEGF led to a marked increase of biochemical markers. Anti-VEGF almost completely suppressed and VEGF markedly enhanced hepatic proliferation in the first 24 h after surgery. This was associated with a modulation of cell cycle control genes (PC4, Gadd45a, Tis21/BTG2), v-jun, and CD14 by VEGF.CONCLUSIONS: VEGF plays an important role in liver regeneration and this may be due in part through its effects on neovascularization. Whether it may, when given therapeutically, represent a strategy to optimize liver regeneration in problematic patients needs to be clarified.
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| 9. |
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| 10. |
- Eriksson, Olof, et al.
(författare)
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The Positron Emission Tomography ligand [11C]5-Hydroxy-Tryptophan can be used as a surrogate marker for the human endocrine pancreas
- 2014
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Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 63:10, s. 3428-3437
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Tidskriftsartikel (refereegranskat)abstract
- In humans a well-developed serotonin system is localized to the pancreatic islets while being absent in exocrine pancreas. Assessment of pancreatic serotonin biosynthesis could therefore be used to estimate the human endocrine pancreas. Proof of concept was tested in a prospective clinical trial by comparisons of type 1 diabetic (T1D) patients, with extensive reduction of beta cells, with healthy volunteers (HV).C-peptide negative (i.e. insulin-deficient) T1D subjects (n=10) and HV (n=9) underwent dynamic Positron Emission Tomography with the radiolabeled serotonin precursor [(11)C]5-Hydroxy-Tryptophan ([(11)C]5-HTP).A significant accumulation of [(11)C]5-HTP was obtained in the pancreas of the HV, with large inter-individual variation. A substantial and highly significant reduction (66%) in the pancreatic uptake of [(11)C]5-HTP in T1D subjects was observed, and this was most evident in the corpus and caudal regions of the pancreas where beta-cells normally are the major constituent of the islets.[(11)C]5-HTP retention in the pancreas was reduced in T1D compared to non-diabetic subjects. Accumulation of [(11)C]5-HTP in the pancreas of both HV and subjects with T1D were in agreement with previously reported morphological observations on the beta cell volume implying that [(11)C]5-HTP retention is a useful non-invasive surrogate marker for the human endocrine pancreas.
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