Alireza Biglarnia

Prompt reversal of a severe complement activation by eculizumab in a patient undergoing intentional ABO-incompatible pancreas and kidney transplantation

Summary We describe the presumably first intentional ABO‐incompatible deceased‐donor kidney and pancreas transplantation with a severe antibody‐mediated rejection during a rebound of isoagglutinins. Rejection was successfully treated with eculizumab, which inhibits the terminal pathway of complement. Complement analysis (C3, C3d,g, and a modified assay of classical complement‐related hemolytic function) documented complement activation and confirmed that eculizumab completely blocked complement function. At 6 months, the patient had normal kidney and pancreas function, and histological evaluations revealed no evidence of sustained graft damage. This successful transplantation suggests that ABO barriers can safely be overcome without extensive preconditioning, when the complement inhibitor eculizumab is included.

Positron Emission Tomography Ligand [11C]5-Hydroxy-Tryptophan Can Be Used as a Surrogate Marker for the Human Endocrine Pancreas

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 β-cells, with healthy volunteers (HVs). C-peptide–negative (i.e., insulin-deficient) T1D subjects (n = 10) and HVs (n = 9) underwent dynamic positron emission tomography with the radiolabeled serotonin precursor [11C]5-hydroxy-tryptophan ([11C]5-HTP). A significant accumulation of [11C]5-HTP was obtained in the pancreas of the HVs, with large interindividual variation. A substantial and highly significant reduction (66%) in the pancreatic uptake of [11C]5-HTP in T1D subjects was observed, and this was most evident in the corpus and caudal regions of the pancreas where β-cells normally are the major constituent of the islets. [11C]5-HTP retention in the pancreas was reduced in T1D compared with nondiabetic subjects. Accumulation of [11C]5-HTP in the pancreas of both HVs and subjects with T1D was in agreement with previously reported morphological observations on the β-cell volume, implying that [11C]5-HTP retention is a useful noninvasive surrogate marker for the human endocrine pancreas.

Screening of mortality in transplant patients using an assay for immune function

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, Fishers 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.

Introducing hand-assisted retroperitoneoscopic live donor nephrectomy: learning curves and development based on 413 consecutive cases in four centers.

Background. Hand-assisted and retroperitoneoscopic techniques reduce the risk of bleeding and intraabdominal complications in living donor nephrectomy (LDN). This study reports on our four-center experience, development, and learning curves from the first 413 LDNs using a hand-assisted retroperitoneoscopic (HARS) technique. Methods. The first 413 consecutive donors operated on using HARS were included in the study. Donor demographics, perioperative and postoperative data, complications, and recipient outcomes have been compiled. The data were analyzed as a whole and separately for each center, looking at center differences and learning curves over time. Results. Significant differences were found in donor demographics between centers for the variables: age, body mass index, number of arteries, and side of operation. Mean operating time was 170.2 min, with significant differences between centers. Operating time was also significantly influenced by learning curves, sex/body mass index, and side of operation. Warm ischemia time differed significantly between centers and was influenced by center-wise learning and number of arteries. Overall conversion rate was 2.4% and differed significantly between centers. There was no mortality and no intraabdominal complications. Apart from the conversions and one pulmonary embolism, there were no major intraoperative or postoperative complications. Overall 3-month graft survival was 99%, with 96% immediate onset of function and 1% ureteral complications. Conclusions. The HARS technique reduces the risk of intraabdominal complications. It can be implemented with excellent donor and recipient outcomes despite different population demographics and center/surgeon-related tradition and experience. On the basis of our experience, we recommend the technique to increase the safety margin of LDN.

Desensitization With Antigen-Specific Immunoadsorption Interferes With Complement in ABO-Incompatible Kidney Transplantation

Background. Complement activation was characterized during and after desensitization treatment in 19 consecutive patients receiving ABO-incompatible (ABOi) living donor kidney transplants to assess the effect of desensitization protocol including antigen-specific immunoadsorption (IA) on complement activation. Methods. All patients received rituximab- and tacrolimus-based triple treatment. Anti-A/B antibodies were removed by IA. Serial determinations of C3, C3a, the C3a/C3 ratio, and sC5b-9 were carried out between day −30 and postoperative day 30. C1q was measured on day −30 and the day before the transplantation. In two recipients, eluates from immunoadsorbent columns were analyzed for C3a, C1q, and immunoglobulins by western blotting. Same complement analysis was performed in eluate from a control column after in vitro perfusion of AB-plasma. Results. Patient and graft survival were 100% for a median follow-up of 40 months (range, 12–60 months). There were no humoral rejections based on ABO-antigen-antibody interactions. C3a and the C3a/C3 ratio declined with the start of IA treatment, and this decline was maintained postoperatively. C1q declined from day −30 to a lower value on the day before transplantation (P<0.05). In eluates from both patient and control, immunoadsorbent column immunoglobulins together with C3a and C1q were detected. Conclusions. The current protocol including antigen-specific IA interferes with the complement system; this effect may be partially responsible for the absence of humoral rejection resulting from ABO-antigen-antibody interactions and the excellent outcomes obtained after ABO-incompatible kidney transplantation.

Obtaining regulatory T cells from uraemic patients awaiting kidney transplantation for use in clinical trials

Adoptive transfer of regulatory T cells (Tregs) has been proposed for use as a cellular therapy to induce transplantation tolerance. Preclinical data are encouraging, and clinical trials with Treg therapy are anticipated. In this study, we investigate different strategies for the isolation and expansion of CD4+CD25highCD127low Tregs from uraemic patients. We use allogeneic dendritic cells (DCs) as feeder cells for the expansion and compare Treg preparations isolated by either fluorescence activated cell sorting (FACS) or magnetic activated cell sorting (MACS) that have been expanded subsequently with either mature or tolerogenic DCs. Expanded Treg preparations have been characterized by their purity, cytokine production and in‐vitro suppressive ability. The results show that Treg preparations can be isolated from uraemic patients by both FACS and MACS. Also, the type of feeder cells used in the expansion affects both the purity and the functional properties of the Treg preparations. In particular, FACS‐sorted Treg preparations expanded with mature DCs secrete more interleukin (IL)‐10 and granzyme B than FACS‐sorted Treg preparations expanded with tolerogenic DCs. This is a direct comparison between different isolation techniques and expansion protocols with Tregs from uraemic patients that may guide future efforts to produce clinical‐grade Tregs for use in kidney transplantation.

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

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.

Initial Experience With Hypothermic Machine Perfusion of Kidneys From Deceased Donors in the Uppsala Region in Sweden

BACKGROUND Simple cold storage (CS) is the gold standard for organ preservation. Recently, evidence has been presented suggesting compared with CS hypothermic machine perfusion (HMP) improves the quality and outcome of kidneys for transplantation. Uppsala has used the LifePort Kidney Transporter to preserve deceased donor kidneys. We evaluated our first single-center 52 cases retrospectively. METHODS Deceased donor kidneys preserved with HMP between July 2010 and July 2012 (n = 52) were compared with a matched historical cohort of organs preserved by CS between January 2009 and July 2012 (n = 87). We evaluated delayed graft function (DGF), creatinine level at hospital discharge, length of hospital stay, incidence of acute rejection episodes during the first year after transplantation, and graft survival. RESULTS Both groups included approximately 69% expanded criteria donors (ECD). Median cold ischemia time (CIT) was 12.8 hours in the HMP group and 11.7 hours in the CS group. The incidence of DGF was 11.5% with HMP and 20.7% with CS. Compared with CS, HMP significantly reduced the occurrence of DGF from 21.4% to 0% using standard criteria kidneys (P = .046), whereas the use of HMP did not impact the occurrence of DGF with ECD kidneys. The creatinine level at hospital discharge was lower after HMP than after CS (P = .047). No difference in graft survival was observed between the groups. CONCLUSIONS Machine perfusion resulted in a lower occurrence of DGF using kidneys from standard criteria donors with a lower creatinine at hospital discharge among the cohort with reasonably low CIT. Using machine perfusion seems to be safe; no adverse surgical events occurred during the study period.

Venous thromboembolism in live kidney donors : a prospective study

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.

Utilization of Small Pediatric Donors Including Infants for Pancreas and Kidney Transplantation : Exemplification of the Surgical Technique and the Surveillance

Utilization of Small Pediatric Donors Including Infants for Pancreas and Kidney Transplantation : Exemplification of the Surgical Technique and the Surveillance