Basic Immunosuppression Research Articles

Herpesvirus, Flavivirus, and Coronavirus Surveillance in Magnificent Frigatebirds (Fregata magnificens), Alcatrazes Archipelago, Southeastern Brazil.

We surveyed the presence of herpesvirus, flavivirus, and coronavirus in 20 Magnificent Frigatebirds (Fregata magnificens) from the protected Alcatrazes Island, Alcatrazes archipelago, Brazil. One adult female was positive for herpesvirus (5% occurrence; 95% confidence interval -5.5 to 15.5), whereas none of the samples were PCR-positive for flavivirus or coronavirus. The obtained herpesvirus was highly similar to the one responsible for annual mortality of Magnificent Frigatebird chicks on Grand Connétable Island, French Guiana; however, no episodes of mass mortality have been recorded in the birds from Alcatrazes. Our findings indicate that this virus may be widespread in Magnificent Frigatebirds of the southwestern Atlantic. The observed differences in morbidity and mortality may be the result of basal immunosuppression of the birds from French Guiana related to environmental or nutritional conditions. The Alcatrazes archipelago sustains the largest frigatebird breeding colony of the southern Atlantic; future monitoring studies with larger sampling sizes are needed to further determine the epidemiologic relevance of the detected herpesviruses, as well as other viruses (e.g., flaviviruses, coronaviruses, avian influenza virus), in seabirds of Alcatrazes Island.

The Cross-Talk between Myeloid and Mesenchymal Stem Cells of Human Bone Marrow Represents a Biomarker of Aging That Regulates Immune Response and Bone Reabsorption

One of the mechanisms that characterizes the aging process of different organs is the accumulation of fat. Different authors have demonstrated that adipose tissue replaces the loss of other cell types, deriving from mesenchymal cells. During aging, there is substitution or trans-differentiation of mesenchymal cells with other cells having the same embryological origin. Newly formed adipocytes were also observed in the trabecular matrix of elderly people’s bones, associated with myeloid cells. In this study, we have investigated the relationship between immature myeloid-derived suppressor cells (I-MDSCs) and mesenchymal stem cells (MSCs) in bone marrow (BM) samples harvested from 57 patients subjected to different orthopedic surgeries. Patients aged from 18 to 92 years were considered in order to compare the cellular composition of bone marrow of young and elderly people, considered a biomarker of immunity, inflammation, and bone preservation. The I-MDSC percentage was stable during aging, but in elderly people, it was possible to observe a strong basal immunosuppression of autologous and heterologous T cells’ proliferation. We hypothesized that this pattern observed in elders depends on the progressive accumulation in the BM of activating stimuli, including cell–cell contact, or the production of different cytokines and proteins that induce the differentiation of bone marrow mesenchymal stem cells in adipocytes. The collected data provided underline the importance of specific biomarkers of aging that promote a reduction in immune response and incremented inflammatory pathways, leading to bone reabsorption in elderly people.

Трансплантация почки от Covid-19-инфицированного трупного донора: каковы последствия для реципиентов?

In recent months, with the spread of COVID 19, the number of kidney transplants from deceased donors has declined significantly in most countries. One of the reasons is the possibility of infection of the recipient with SARS-CoV-2. Determining the risk of transmission of COVID 19 with a donor organ is very important for developing a kidney transplantation policy during a pandemic.We present cases of kidney transplantation from COVID 19 positive deceased donor to two dialysis patients in single center. Deceased donor: a 45 years old man with diabetes, who had a major hemorrhagic stroke resulting in brain death. He had normal urine output and serum creatinine level for last 24 hours before kidney harvesting. For a few hours after organ harvesting, the donor was diagnosed COVID 19 (retrospective nasopharyngeal swab rRT-PCR which was confirmed by morphological examination and RNA-PCR of specimens from the trachea and bronchus). Recipient 1: a 49 years old man with polycystic kidney disease had been on hemodialysis for 28 months. He was in urgent list because of problems with vascular access. So non identical ABO (0-donor, B-recipient) kidney transplantation from this deceased donor was done in May 2020. Recipient 2: a 45 years old man with polycystic kidney disease on continuous ambulatory peritoneal dialysis (CAPD). was registered on urgent waiting list because of low transport capacity of peritoneum. Kidney transplantation from the same deceased donor was done at the same time. In both cases we completely abandoned any antilymphocytic agents for induction, despite non ABO identical transplantation in one of the recipients and the delayed graft function. Both patients received only basic immunosuppression, including tacrolimus, methylprednisolone and a mycophenolic acid.In first case cold ischemia time was 22 hours. The recipient had delayed graft function with increasing of urine output on day 8 post-transplant. No other deviations from the usual course were seen during hospital stay. The patient was discharge from hospital with serum creatinine level 122 mkmol/L. The cold ischemia time was 21 hours in another patient. Graft function was immediate with a decrease serum creatinine to 92.5 mkmol/L at discharge. Both patients had no febrile and no other symptoms of acute respiratory disease during all hospital stay. No abnormalities on chest X-ray were seen. No serum anti-SARS-CoV-2 IgM and IgG were detected before and during 6 weeks after surgery. Repeated nasopharyngeal swabs rRT-PCR were negative during all the period. Both recipients were discharged for 5 weeks after surgery to prevent out-of-hospital contamination of COVID 19, which would be difficult to differentiate from transmission infection. After 9 months both patients are doing well with no clinical or laboratory signs of COVID-19.Today we have no evidence of the possibility of transmission of COVID-19 from a SARS-Cov-2 positive donor to a kidney recipient. We also have no reason to suspect kidney damage by COVID-19 in a deceased donor at normal serum creatinine level. Avoiding the use of anti-lymphocyte drugs for induction of immunosuppression may also reduce the risk of developing COVID19 after transplantation. A careful collection and analysis of such dates is necessary to develop modern practical recommendations for transplant centers.

Is Kidney Transplantation From a COVID-19–Positive Deceased Donor Safe for the Recipient?

IntroductionIn recent months, the number of kidney transplants from deceased donors has declined significantly. One of the reasons is the possibility of infection of the recipient with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Determining the risk of transmission of coronavirus disease 2019 (COVID-19) with a donor organ is very important for developing a kidney transplantation policy during a pandemic. Materials and methodWe present cases of kidney transplantation from COVID-19–positive deceased donors to 2 dialysis patients 49 and 45 years old. One of them was on hemodialysis for 28 months; the other received continuous ambulatory peritoneal dialysis (CAPD). Both patients received only basic immunosuppression, including tacrolimus, methylprednisolone, and mycophenolic acid. No antilymphocyte agents were used for induction therapy. ResultsCold ischemia time was 22 and 21 hours, respectively. One recipient had delayed graft function with increasing of urine output on day 8; another had immediate function.Both patients had no febrile and no other symptoms of acute respiratory disease during their hospital stay. No abnormalities on the chest x-ray were seen. No serum anti-SARS-CoV-2 IgM and IgG were detected before and during 6 weeks after surgery. Repeated nasopharyngeal swabs real-time reverse transcription polymerase chain reaction (rRT-PCR) were negative during the period. Both recipients were discharged 5 weeks after surgery with serum creatinine levels of 122 and 91 mcmol/L, respectively. ConclusionToday we have no evidence of the possibility of transmission of COVID-19 from a SARS-CoV-2 positive donor to a kidney recipient. We also have no reason to suspect kidney damage by COVID-19 in a deceased donor at normal serum creatinine level.

Acute Rejection Following Kidney Transplantation: State-of-the-Art and Future Perspectives.

Although acute renal graft rejection rate has declined in the last years, and because an adequate therapy can improve graft outcome, its therapy remains as one of the most significant challenges for pharmacists and physicians taking care of transplant patients. Due to the lack of evidence highlighted by the available metaanalyses, we performed a narrative review focused on the basic mechanisms and current and future therapies of acute rejection in kidney transplantation. According to Kidney Disease/Improving Global Outcomes (KDIGO) guidelines, both clinical and subclinical acute rejection episodes should be treated. Usually, high dose steroids and basal immunosuppression optimization are the first line of therapy in treating acute cellular rejection. Rabbit antithymocytic polyclonal globulins are used as rescue therapy for recurrent or steroid-resistant cellular rejection episodes. Current standard-of-care (SOC) therapy for acute antibody-mediated rejection (AbMR) is the combination of plasma exchange with intravenous immunoglobulin (IVIG). Since a significant rate of AbMR does not respond to SOC, different studies have analyzed the role of new drugs such as Rituximab, Bortezomib, Eculizumab and C1 inhibitors. Lack of randomized controlled trials and heterogenicity among performed studies limit obtaining definite conclusions. Data about new direct and indirect B cell and plasma cell depleting agents, proximal and terminal complement blockers, IL-6/IL-6R pathway inhibitors and antibody removal agents, among other promising drugs, are reviewed.

Outcome of ABO Blood Type–Incompatible Living-Related Donor Kidney Transplantation Under a Contemporary Immunosuppression Strategy in Japan

BackgroundBecause of the serious donor shortage in Japan, there is an increasing need for ABO blood type–incompatible kidney transplantation (ABOi-KT) in living-related donor kidney transplantation. We evaluated the outcomes of ABOi-KT performed at our hospitals using a contemporary immunosuppression strategy with low-dose rituximab. Patients and MethodsBetween June 2006 and April 2019, 107 patients underwent living-related donor kidney transplantation at our hospitals. The patients were divided into ABO-compatible (ABOc) and ABOi groups. The basic immunosuppression regimen differed between the 2 groups in the use of low-dose rituximab and therapeutic apheresis in the ABOi group. We compared graft survival, patient survival, rejection, viral infection, and posttransplant renal function between the 2 groups. ResultsOf 107 recipients, 37 (35%) underwent ABOi-KT. The 5-year graft survival rates in the ABOc and ABOi group were 91% and 100%, respectively. The Kaplan-Meier analyses showed no difference in graft survival (P = .168) or patient survival (P = .873) between the groups. Biopsy-proven rejection in the ABOc and ABOi groups was observed in 13 (19%) and 7 (19%) patients, respectively (P = .965), and viral infection was observed in 21 (30%) and 10 (27%) patients (P = .747), respectively. Renal function by estimated glomerular filtration rate from 1 week to 5 years after transplantation was similar in both groups. ConclusionsThe outcomes of ABOi-KT with low-dose rituximab were comparable with those of ABOc-KT at our hospitals. ABOi-KT with proper immunosuppression may be an option to help resolve the severe donor shortage in Japan.

Cytomegalovirus Infections are Frequent after Heart Transplantation but Do Not Increase the Risk of Biopsy-Proven Allograft Rejection in the Modern Era

Our aim was to analyze the clinical impact of CMV infections on the risk of allograft rejection. We conducted a single-center retrospective study including patients transplanted between January 2012 and December 2016 who had at least one endomyocardial biopsy (EMB) during follow-up. Patients at high risk of CMV infections (D+/R-) received valganciclovir prophylaxis for 3 months, those at intermediate risk (R +) were treated according to a preemptive strategy (viral replication threshold: 10,000 IU / mL). Protocol monitoring included 13 B.M. per patient in the first year. Allograft rejection was defined as ≥ 1R1B acute cellular rejection or ≥ pAMR1 antibody-mediated rejection according to international guidelines. The impact of CMV infection, defined as a viral replication ≥ 10,000 IU / mL, on the risk of allograft rejection was analyzed using a mixed effects logistic regression. 399 patients met the inclusion criteria, including 60 patients D+/ R-, 256 R+ and 72 D+/R. All patients received an induction therapy and a triple basal immunosuppression. We observed a dynamic risk of infection during the first year according to the baseline CMV serology (Figure 1A). CMV infections were diagnosed in more than half of the patients (Figure 1B). 140 patients (35%) had at least one episode of biopsy-proven rejection. In univariable analyses, CMV infections were not associated with an increased risk of rejection in month following infection (0R=1.03, 95%CI=0.6-1.7, p=0.91). After adjustment for the presence of DSA, the number of HLA AB-DR-DQ mismatches, recipient age and time post-transplant, CMV infections were not associated with the risk of rejection in month following infection (OR=0.9, 95%CI=0.5-1.5, p=0.61). Different timing post-infection have been evaluated but were not associated with rejection. CMV infections were common after heart transplantation but were not associated with the risk of allograft rejection.

Worldwide First Successful and Reproducable Long-Term Survival up to Half a Year: Completed Preclinical Study with Life-Supporting Orthotopic Pig-to-Baboon Cardiac Xenotransplantation (oXHTx) Fullfilling the ISHLT Prerequisite for Clinical Cardiac Xenotransplantation

Major hurdles in oXHTx are the delayed xenograft rejection, the early perioperative cardiac xenograft dysfunction (PCXD) and the pig heart overgrowth, which were solved in this study with a costimulation blockade, a new non-ischemic cold preservation and a growth inhibition by anti-proliferative drugs. Aim was to achieve a 90-days-survival of minimal 60% (6 of 10 baboons) in this life-supporting orthotopic pig-to-baboon model (oXHTx), because this is the recommendation of the ISHLT to begin a clinical cardiac XT program. We transplanted 8 GalKO/hCD46/hTM transgenic (tg) pig hearts orthotopically into baboons with using a basic immunosuppression consisting of ATG, rituximab, mycophenolate (MMF), cortisone and a costimulation blockade CD40mAb (high dose: 50 mg/kg). To prevent PCXD, we used instead of the crystalloid solution a new non-ischemic 8°C cold perfusion technique with oxygenated erythrocytes. Additional antihypertensive drugs and an mTOR inhibitor (temsirolimus) were applied to inhibit pig xenograft growth and hypertrophy. In comparison to our previous group with crystalloid cardioplegia (Längin et al. Nature. 2018;564:430-433) in this group with cold perfusion preservation (non-ischemic) no PCXD was found. One baboon died of a pancreatitis on day 14, another of sepsis on day 26. By using the antiproliferative therapy, 6 of 8 recipient baboons reached the end of study, were long-term surviving (4 were actively terminated after 90 days according to the guidelines of our government). With special permit two further experiments could be prolonged to half a year and the animals were terminated on day 182 and 195. All baboons lived under excellent physical conditions and no hyperacute rejection or DXR occurred. First time in a life-supporting oXHT of multi-tg pig hearts here was a consistent reproduceable long-term survival of 3 - 6 months achieved, which is a major progress after 25 years of research. This is an essential milestone and breakthrough and meets the prerequisite according to the ISHLT to begin a clinical phase I study with patients in terminal heart failure. This paves the way to clinical cardiac XT in the next 2 to 5 years.

Steroid-free immunosuppression with low-dose tacrolimus is safe and significantly reduces the incidence of new-onset diabetes mellitus following liver transplantation

Objectives: Corticosteroids (CS) are traditionally used as part of the basal immunosuppression (IS) following liver transplantation (LT) but are known to be associated with an increased risk of new-onset diabetes mellitus (NODM), cardiovascular morbidity and mortality. The aim of this study was to retrospectively compare the incidence of transient as well as persistent NODM, rejection rate and patient- and graft survival between patients receiving steroid-based and steroid-free maintenance IS.Materials and Methods: A total of 238 patients liver transplanted (2008–2011) with deceased donor livers were divided into two groups, one group that received steroid-based IS (tacrolimus (TAC), corticosteroids (CS), ± mycophenolate mofetil (MMF); n = 155) (2008–2011) and another group of non-autoimmune recipients that received steroid-free IS (TAC, MMF; n = 83) according to our new maintenance IS-protocol starting January 2010. The primary and secondary end-points were patient- and graft survival, rejection rates and the incidence of NODM. The median follow-up times were 1248 days and 681 days, respectively.Results: The one-year patient- and graft survival in the steroid-based and steroid-free group was 92.7% and 93.3% (ns) and 87.6% and 84.9% (ns), respectively. The incidence of biopsy proven acute rejection (BPAR) was 27.7% in both groups (ns) during follow-up. The overall incidence of persistent NODM in the two groups were 16.8% and 2.9%, respectively (p < .01).Conclusions: The results show that steroid-free low-dose tacrolimus-based IS following LT is safe and decreases the incidence of NODM significantly.

Delayed revascularization of islets after transplantation by IL-6 blockade in pig to non-human primate islet xenotransplantation model.

Pancreatic islet transplantation is currently proven as a promising treatment for type 1 diabetes patients with labile glycemic control and severe hypoglycemia unawareness. Upon islet transplantation, revascularization is essential for proper functioning of the transplanted islets. As IL-6 is important for endothelial cell survival and systemic inflammation related to xenograft, the effect of IL-6 receptor antagonist, tocilizumab, on revascularization of the transplanted islets was examined in pig to non-human primate islet xenotransplantation model. Also, the endothelial cell origin in a new vessel of the transplanted pig islets was determined. Pig islets were isolated from designated pathogen-free (DPF) SNU miniature pigs and transplanted via portal vein into five streptozotocin-induced diabetic monkeys. One group (n=2, basal group) was treated with anti-thymoglobulin (ATG), anti-CD40 antibody (2C10R4), sirolimus, and tacrolimus, and the other group was additionally given tocilizumab on top of basal immunosuppression (n=3, Tocilizumab group). To confirm IL-6 blocking effect, C-reactive protein (CRP) levels and serum IL-6 concentration were measured. Scheduled biopsy of the margin of the posterior segment right lobe inferior of the liver was performed at 3weeks after transplantation to assess the degree of revascularization of the transplanted islets. Immunohistochemical staining using anti-insulin, anti-CD31 antibodies, and lectin IB4 was conducted to find the origin of endothelial cells in the islet graft. CRP significantly increased at 1~2days after transplantation in Basal group, but not in Tocilizumab group, and higher serum IL-6 concentration was measured in latter group, showing the biological potency of tocilizumab. In Basal group, well-developed endothelial cells were observed on the peri- and intraislet area, whereas the number of CD31+ cells in the intraislet space was significantly reduced in Tocilizumab group. Finally, new endothelial cells in the pig islet graft were positive for CD31, but not for lectin IB4, suggesting that they are originated from the recipient monkey. Our results demonstrated that tocilizumab can delay revascularization of the transplanted islet, although this effect had no significant correlation to the overall islet graft survival. In the pig to NHP islet xenotransplantation model, the endothelial cells from recipient monkey form new blood vessels in and around pig islets.

T-cell regulation through a basic suppressive mechanism targeting low-density lipoprotein receptor-related protein 1.

Cell adhesion is generally considered to depend on positive regulation through ligation of integrins and cytokine receptors. However, here we show that T-cell adhesion, and notably also T-cell receptor (TCR) -induced activation, are subject to constant suppression through shedding of low-density lipoprotein receptor-related protein 1 (LRP1). The broad-spectrum metalloprotease inhibitor GM6001 abrogated shedding, so inducing prominent cell surface expression of LRP1 while enhancing TCR-induced activation and adhesion to β1 and β2 integrin ligands, hence arresting the cells. Integrin ligands also inhibited shedding but the effect was less potent than that of GM6001. Unlike GM6001, integrin ligands also induced cell surface expression of full-length thrombospondin-1 (TSP170) and TSP130, which associated with LRP1, and TSP110, which did not associate with LRP1. Cell surface expression of LRP1 and TSP130 were induced exclusively in adhering cells, expression of TSP110 preferentially in non-adhering cells and expression of TSP170 correlated with T-cell motility. The pro-adhesive chemokine CXCL12 also inhibited LRP1 shedding and induced surface expression of TSP170 and TSP130 while inhibiting TSP110. Exogenous TSP-1 and ligation of CD28 inhibited shedding although less effectively than GM6001, and the inhibition through CD28 was independent of TSP-1. Small interfering RNA silencing experiments confirmed involvement of LRP1 and TSP-1 in integrin-dependent adhesion and TCR-induced activation. Hence, the poor LRP1 expression in T cells depends on shedding. Integrin ligands and CXCL12 antagonize shedding through a TSP-1-dependent pathway and ligation of CD28 antagonizes shedding independent of TSP-1. The disappearance of LRP1 from the cell surface may provide basic immunosuppression at the T-cell level.

Tuberculosis and Transplantation.

Mycobacterium tuberculosis is a major opportunistic pathogen in transplant recipients. Compared to that in the general population, the frequency of tuberculosis (TB) is 10 to 40 times higher in hematopoietic stem cell transplant (HSCT) recipients and 20 to 74 times higher in solid-organ transplant (SOT) recipients. Transplant recipients with TB are also more likely to develop disseminated disease, have longer time to definitive diagnosis, require more invasive diagnostic procedures, and experience greater anti-TB treatment-related toxicity than the general population. Specific risk factors for TB in SOT recipients include previous exposure to M. tuberculosis (positive tuberculin skin tests and/or residual TB lesions in pretransplant chest X ray) and the intensity of immunosuppression (use of antilymphocyte antibodies, type of basal immunosuppression, and intensification of immunosuppressive therapy for allograft rejection). Risk factors in HSCT recipients are allogeneic transplantation from an unrelated donor; chronic graft-versus-host disease treated with corticosteroids; unrelated or mismatched allograft; pretransplant conditioning using total body irradiation, busulfan, or cyclophosphamide; and type and stage of primary hematological disorder. Transplant recipients with evidence of prior exposure to M. tuberculosis should receive treatment appropriate for latent TB infection. Optimal management of active TB disease is particularly challenging due to significant drug interactions between the anti-TB agents and the immunosuppressive therapy. In this chapter, we address the epidemiology, clinical presentation, diagnostic considerations, and management strategies for TB in SOT and HSCT recipients.

Outcomes in Renal Transplant Recipients With Lupus Nephritis—A Single–Center Experience and Review of the Literature

BackgroundRenal transplantation is the renal replacement therapy of choice in patients with end–stage lupus nephritis (LN). The aim of this study was to evaluate the early and late outcomes of renal transplantation in LN patients in a single transplant center. Patients and MethodsThis study analyzed the clinical data of patients who received a renal transplant (RTx) at Gdańsk Transplantation Centre between January 1999 and December 2014. ResultsThere were 1296 RTx performed between January 1999 and December 2014, including 21 RTx in 19 LN patients (mean age 40 ± 10 years, 89% female). During the follow–up period (between 1 month and 10.5 years), 1 patient died of urosepsis and 1 of pneumonia. Three RTx recipients with antiphospholipid syndrome lost 5 kidney allografts, including 3 due to acute rejection (AR) during the first posttransplantation month. Kidney allograft survival median was 64 months. Delayed graft function (DGF) and AR were observed in 48% and 33% vs 31% and 21% of LN patients and other RTx patients, respectively (P = .1 and P = .16 for DGF and AR, respectively). The most common early posttransplantation complications were AR (31%) and perirenal hematomas (29%), and late complications were urinary tract infections (75%). Recurrence of LN in renal allograft was observed in 1 patient and was successfully treated by increasing the basic immunosuppression. ConclusionsSecondary antiphospholipid syndrome has a major influence on the outcomes of RTx in LN patients. Recurrence of LN has no clinical significance.

Nephropathy Evolving Within the First Two Posttransplant Months With No Typical Cytopathic Lesions: Two Cases Presentation

BackgroundWe report 2 cases of polyomavirus-associated nephropathy (PyVAN) emerging within the initial 8 posttransplant weeks. These cases were characterized by intraepithelial BK virus replication without typical nuclear inclusions in epithelial cells. Methods and ResultsA 70-year-old male recipient of a cadaveric kidney transplant had experienced unsatisfying graft function since the time of transplantation (Tx). One month after Tx, results of a graft biopsy revealed mild tubulointerstitial inflammation. No intraepithelial nuclear inclusions suggestive of viral infection were present at that time. The patient received intravenous methylprednisolone, and the dosage of tacrolimus was increased. Due to a further drop in the glomerular filtration rate, a subsequent kidney biopsy was performed during posttransplant week 10, which revealed lesions typical of PyVAN. Retrospectively performed SV40 staining revealed that intragraft polyomavirus replication was already present on posttransplant day 30. Basic immunosuppression reduction and ciprofloxacin administration were followed by BK viremia elimination, stabilization of graft function, and resolution of PyVAN. In another patient, a 62-year-old male recipient of a cadaveric renal graft, BK viremia was monitored from the time of Tx. Two months after Tx, the patient was found to have a BK viral load of 6 × 4 log10/mL. Results of the graft biopsy revealed fully preserved tubular epithelium, but SV40 staining was positive in some of these cells. After basic immunosuppression reduction and introduction of ciprofloxacin, the BK viral load dropped to 1 × log10/mL with graft function stabilization. ConclusionsPyVAN may emerge as early as 4 weeks after Tx, with near-normal or acute rejection–like graft morphology. The early monitoring of plasma BK viral load, as well as SV40 staining, avoids misdiagnosis of this severe posttransplant complication.

Plasmapheresis, Photopheresis, and Endovenous Immunoglobulin in Acute Antibody-mediated Rejection in Kidney Transplantation

IntroductionAcute antibody-mediated rejection (AAMR) is the subject of much research. It is diagnosed by C4d staining at biopsy and circulating donor-specific antibodies (DSA). The combination of intensive plasmapheresis and intravenous immunoglobulin (IVIG) has been recognized as an effective treatment for AAMR. We report our single-center experience on AAMR treatment. Materials and MethodsWe treated 23 transplanted patients (group A) with protein-A immunoadsorption (IA) and 7 patients (group B) with double-filtration plasmapheresis. All patients were treated with IVIG (400 mg/kg/d). Basic immunosuppression included cyclosporine, steroids, azathioprine, and antilymphocyte globulin or monoclonal antibodies (OKT3). A subgroup of 3 patients (3/7; group B1) was treated with photopheresis. ResultsIn both groups, the mean number of extracorporeal procedures was 7.3 ± 4.5 and 5.5, respectively; the mean duration of treatment was 12.3 ± 10.2 and 14.5 days, respectively. In group A, we observed negative cross-matching in 96% after mean of 18 days; 1 patient died from sepsis, and 6 lost their grafts. In group B, negative circulating DSA were observed in all patients after a mean of 25 days, and 1 patient lost their allograft. ConclusionsIn our observation, the 2 extracorporeal procedures had similar effects in terms of graft survival, DSA removal, and cross-match negativity (group A 74% vs 86%; 95.6% vs 100%). IA was faster for DSA removal. In our opinion, the higher costs of IA suggests its use just in high-risk cases, such as in hyperimmune or sensitized patients. Further studies are necessary to improve our knowledge.

Looking Behind the Curtain: Pre-Transplant Mismatched Eplet Load May Better Predict Increases in Post-Transplant DSA.

Purpose: Patients receiving renal transplants in the presence of donor specific HLA antibodies (DSA) are at increased risk for antibody mediated rejection (AMR) as well as decreased graft survival. For highly sensitized patients, transplanting in the presence of low/moderate DSA may be the only viable option. We looked at which characteristics of pre-existing DSA are associated with poor post-transplant(tx) outcomes. Methods: We identified 11 patients (mean cPRA=87+7%) with DSAs from a cohort of 165 consecutive renal txs performed between 10/2012 and 12/2013. Patients were desensitized using plasmapheresis(PP) and IVIg and received standard induction and maintenance therapy post-tx. DSA titers and MFI were determined by solid phase assays (pre-Tx, day 3, weekly 1-4, months 2, 3, 6, 9, 12). Donor-recipient eplet mismatches (MM) in the DSA-associated HLA antigens were determined using HLA Matchmaker. Results: Post-tx, 5 of the 11 (45.5%) desensitized patients no longer had clinically significant DSA. Increased DSA were found in the remaining 6 (55.5%) within 2 weeks (MFI=3469-15000, titers 1:16->1:1024) and 5 developed de novo DSA. No association between pre-tx MFI values, positive xmatch (T or B), or previous tx and increased post-tx DSA was found. In contrast, patients with negative DSA post-tx averaged 6.4+3.6 eplet MM in pertinent HLA antigen, whereas those with increasing DSA post-tx averaged 16.8+5.6 MM eplets.Expression of Cytosolic DoubleFigure: No Caption available.Increased DSA were successfully reversed in 2 patients with PP and IVIg and in 1 with increased basal immunosuppression. The remaining 3, after treatment, have DSA levels that are stable or slightly lower with surviving but sub-optimal graft function. Conclusions: Renal transplants may be performed successfully in presence of DSA, but remain at increased risk for graft failure or poor function. Our data suggest that mismatched eplet load is predictive of clinically significant post-tx DSA and may identify patients in need of frequent monitoring and aggressive early intervention to minimize DSA load and improve outcomes.

Successful Multiple Pancreas Retransplantation in Combination To Renal Retransplantation: A Single Center Experience.

Purpose: Retrospective analysis of long term results regarding patient and graft survival, graft function and major complications in two patients after combined pancreas 4th-kidney 3rd and pancreas 3rd-kidney 2nd transplantation performed at our center. Methods: Patient 1: A 47 years old type I diabetic woman underwent a combined 4thpancreas - 3rd kidney transplantation after totally 2 immunological renal and 2 thrombotic pancreas graft losses and one immunological pancreas graft loss (explantation of the 2 previous kidney- and 2 pancreas-grafts). Cold ischemia time: 12:56 hours in the kidney and 15:14 in the pancreas. Patient 2: A 51 years old type diabetic men underwent a combined 3rd pancreas - 2nd kidney transplantation after immunological kidney and pancreas graft losses (explantation of the kidney graft). Cold ischemia time: 09:43 hours in the kidney of 09:43 hours and 11:30 in the pancreas. The multiple retransplantations were performed due to standard techniques. The basic immunosuppression consisted of Alemtuzumab, steroids, Tacrolimus, CellCept. The triple drug immunosuppression was maintained within a mean Tacrolimus trough level of 6 ng/mL until the current follow up time of 31 and 35 months posttransplant, respectively. Both patients are on permanent anticoagulation. Results: No immunological complication occurred apart from one reversible acute kidney rejection in patient 2 in month 1. Both patients are currently well within a stable pancreas and kidney function (mean serum creatinine 1.45 mg/dL, blood glucose 80 mg/dL). Leucopenia, thrombocytopenia, bacterial sepsis and chronic hepatitis C as major complications were controllable. Conclusion: Good results can be achieved in multiple pancreas- retransplantations in combination to a simultaneous renal transplantation. An explantation of previously non functioning grafts could be favorable. An exact immunosuppression and careful monitoring basing on an excellent patients adhaerance would contribute to good long term results.

Fourteen Successful Consecutive Cases of ABO-Incompatible Living Donor Liver Transplantation: New Simplified Intravenous Immunoglobulin Protocol Without Local Infusion Therapy

Since various innovative strategies including local infusion therapy and rituximab have been introduced, the survivals and outcomes of recipients in ABO-incompatible (ABO-I) living donor liver transplantation (LDLT) have remarkably improved. Thus, ABO-I LDLT can be a feasible therapeutic option for the patient with end-stage liver disease if an ABO-compatible donor is not available. Although most ABO-I protocols are based on rituximab, plasma exchange, and local infusion therapy, treatment strategies have been changing according to a center's preference or their results. Nonetheless, the consensus of the ABO-I LDLT protocol remains undetermined. Herein, we present our experience with new simple ABO-I LDLT protocol and the excellent results for 14 patients from January 2011 to May 2013. All patients were administrated a single dose of rituximab over 7 days before transplantation followed by plasma exchange to lower anti-ABO antibody titer ≤32. The basic immunosuppression protocol consisted of tacrolimus and steroids with mycophenolate mofetil starting 3 days before transplantation. Splenectomy was not performed routinely and local infusion therapy was not applied at the postoperative period. Instead, the patients received intravenous immunoglobulin (IVIG) after LDLT on days 1, 3, and 5. Neither antibody-mediated rejection nor biliary stricture were encountered in the patients, with a mean follow-up of 16.27 ± 9.4 months. This new simplified ABO-I LDLT protocol seems to prevent antibody-mediated rejection and could be considered as the safe and effective modality to overcome the ABO blood-type barrier in LDLT.

Managing End-Stage Renal Disease in Older Patients: A Single Centre Experience with Renal Transplantation in the Elderly

The increase of patients developing end-stage renal disease (ESRD) has occurred predominantly in the older adult population. As a consequence, the nephrologists will need to decide whom of these older patients are siutable for transplantation. There are very few absolute contraindications, such as active infection and recent malignancy, but there are many relative or potential contraindications in older patients. Worldwide, organs available for transplantation are limited. Some centers are reluctant to use organs from expanded criteria donors also in elderly recipients. This leads to long waiting lists and many older patients will die while they are waiting for an organ. It is vital that the patients who are accepted for renal transplantation are those who will derive most benefit, and correct selection of patients and donor organs is therefore of outmost importance. This paper describes the previous and planned research our research group has performed with focus on older renal transplant recipients with special emphasis on survival, basic immunosuppression, selection of organs, and health related quality of life.

Outcome Comparison of ABO-Incompatible Kidney Transplantation With Low-Dose Rituximab and ABO-Compatible Kidney Transplantation: A Single-Center Experience

BackgroundThe development of immunosuppressive techniques has helped overcome the ABO incompatibility barrier. However, the outcomes of ABO-incompatible (ABOi) kidney transplantation remain a controversial issue with the advent of the anti-CD20 chimeric antibody rituximab. Herein, we report the outcomes of ABOi kidney transplantation with low-dose rituximab. Patients and MethodsBetween June 2006 and April 2013, 42 patients underwent living-related kidney transplantation at our hospital. The patients were divided into 2 groups: ABO-compatible (ABOc; n = 29) and ABOi kidney transplants using low-dose rituximab (100 mg/m2) without splenectomy (n = 13). The basic immunosuppression regimen (calcineurin inhibitor [CNI], mycophenolate mofetil [MMF], and steroids) was the same for both groups, except for the use of rituximab and therapeutic apheresis in the ABOi group. We compared post-transplantation renal function, incidents of virus infection, episodes of rejection, and graft survival between the 2 groups. ResultsIn our hospital, 30% of recipients received ABOi kidney transplants. The estimated glomerular filtration rate (eGFR) did not differ between the groups. Rejection episodes confirmed by biopsy in the ABOc and ABOi groups were 8 (28%) and 4 (31%) patients (P = .833), acute antibody-mediated rejection was observed in 1 (3.5%) and 2 (15%) patients (P = .165), and virus infection was observed in 14 (48%) and 3 (23%) patients (P = .252), respectively. The 5-year patient survival rate was 100% in both groups, and the 5-year graft survival rates were 95% for ABOc and 100% for ABOi transplants (P = .527). ConclusionsThese results suggest that the outcomes of ABOi kidney transplantation with low-dose rituximab are similar to those of ABOc kidney transplantation. Further study is necessary to address the efficacy and safety of ABOi kidney transplantation.