ABSTRACT
Children have reduced severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection rates and a substantially lower risk for developing severe coronavirus disease 2019 compared with adults. However, the molecular mechanisms underlying protection in younger age groups remain unknown. Here we characterize the single-cell transcriptional landscape in the upper airways of SARS-CoV-2-negative (n = 18) and age-matched SARS-CoV-2-positive (n = 24) children and corresponding samples from adults (n = 44), covering an age range of 4 weeks to 77 years. Children displayed higher basal expression of relevant pattern recognition receptors such as MDA5 (IFIH1) and RIG-I (DDX58) in upper airway epithelial cells, macrophages and dendritic cells, resulting in stronger innate antiviral responses upon SARS-CoV-2 infection than in adults. We further detected distinct immune cell subpopulations including KLRC1 (NKG2A)+ cytotoxic T cells and a CD8+ T cell population with a memory phenotype occurring predominantly in children. Our study provides evidence that the airway immune cells of children are primed for virus sensing, resulting in a stronger early innate antiviral response to SARS-CoV-2 infection than in adults.
Subject(s)
Bronchi/immunology , Bronchi/virology , COVID-19/immunology , COVID-19/virology , Immunity, Innate , SARS-CoV-2/immunology , Adolescent , Adult , Aged , CD8-Positive T-Lymphocytes/immunology , Child , Child, Preschool , DEAD Box Protein 58/metabolism , Dendritic Cells/immunology , Epithelial Cells/immunology , Epithelial Cells/virology , Female , Humans , Infant , Infant, Newborn , Interferon-Induced Helicase, IFIH1/metabolism , Macrophages/immunology , Male , Middle Aged , Receptors, Immunologic/metabolism , Single-Cell Analysis , T-Lymphocytes, Cytotoxic/immunology , Young AdultABSTRACT
Hepatocyte transplantation (HcTx) is a promising approach for the treatment of metabolic diseases in newborns and children. The most common application route is the portal vein, which is difficult to access in the newborn. Transfemoral access to the splenic artery for HcTx has been evaluated in adults, with trials suggesting hepatocyte translocation from the spleen to the liver with a reduced risk for thromboembolic complications. Using juvenile Göttingen minipigs, we aimed to evaluate feasibility of hepatocyte transplantation by transfemoral splenic artery catheterization, while providing insight on engraftment, translocation, viability, and thromboembolic complications. Four Göttingen Minipigs weighing 5.6 kg to 12.6 kg were infused with human hepatocytes (two infusions per cycle, 1.00E08 cells per kg body weight). Immunosuppression consisted of tacrolimus and prednisolone. The animals were sacrificed directly after cell infusion (n=2), 2 days (n=1), or 14 days after infusion (n=1). The splenic and portal venous blood flow was controlled via color-coded Doppler sonography. Computed tomography was performed on days 6 and 18 after the first infusion. Tissue samples were stained in search of human hepatocytes. Catheter placement was feasible in all cases without procedure-associated complications. Repetitive cell transplantations were possible without serious adverse effects associated with hepatocyte transplantation. Immunohistochemical staining has proven cell relocation to the portal venous system and liver parenchyma. However, cells were neither present in the liver nor the spleen 18 days after HcTx. Immunological analyses showed a response of the adaptive immune system to the human cells. We show that interventional cell application via the femoral artery is feasible in a juvenile large animal model of HcTx. Moreover, cells are able to pass through the spleen to relocate in the liver after splenic artery infusion. Further studies are necessary to compare this approach with umbilical or transhepatic hepatocyte administration.
Subject(s)
Hepatocytes/transplantation , Liver/cytology , Splenic Artery , Animals , Catheterization/methods , Cell Transplantation/adverse effects , Cell Transplantation/methods , Hepatocytes/cytology , Hepatocytes/enzymology , Hepatocytes/immunology , Humans , Immunosuppression Therapy , Liver/enzymology , Liver/pathology , Models, Animal , Portal Vein/cytology , Spleen/cytology , Spleen/diagnostic imaging , Spleen/pathology , Splenic Artery/cytology , Swine , Swine, Miniature , Time Factors , Tomography, X-Ray Computed , Ultrasonography, DopplerABSTRACT
Ever since its first application in clinical medicine, scientists have been urged to induce tolerance towards foreign allogeneic transplants and thus avoid rejection by the recipient's immune system. This would circumvent chronic use of immunosuppressive drugs (IS) and thus avoid development of IS-induced side effects, which are contributing to the still unsatisfactory long-term graft and patient survival after solid organ transplantation. Although manifold strategies of tolerance induction have been described in preclinical models, only three therapeutic approaches have been utilized successfully in a still small number of patients. These approaches are based on (i) IS withdrawal in spontaneous operational tolerant (SOT) patients, (ii) induction of a mixed chimerism and (iii) adoptive transfer of regulatory cells. Results of clinical trials utilizing these approaches show that tolerance induction does not work in all patients. Thus, there is a need for reliable biomarkers, which can be used for patient selection and post-therapeutic immune monitoring of safety, success and failure. In this review, we summarize recent achievements in the identification and validation of such immunological assays and biomarkers, focusing mainly on kidney and liver transplantation. From the published findings so far, it has become clear that indicative biomarkers may vary between different therapeutic approaches applied and organs transplanted. Also, patient numbers studied so far are very small. This is the main reason why nearly all described parameters lack validation and reproducibility testing in large clinical trials, and are therefore not yet suitable for clinical practice.
Subject(s)
Graft Survival , Immunosuppressive Agents/therapeutic use , Liver Transplantation , Monitoring, Immunologic/methods , Transplantation Tolerance , Animals , Biomarkers , Humans , Immunosuppressive Agents/adverse effects , Transplantation, HomologousSubject(s)
Immune Tolerance , Liver Transplantation , Graft Rejection , Graft Survival , Humans , Transplantation ToleranceABSTRACT
Abdominal wall transplantation (AWTX) has revolutionized difficult abdominal closure after intestinal transplantation (ITX). More important, the skin of the transplanted abdominal wall (AW) may serve as an immunological tool for differential diagnosis of bowel dysfunction after transplant. Between August 2008 and October 2014, 29 small bowel transplantations were performed in 28 patients (16 male, 12 female; aged 41 ± 13 years). Two groups were identified: the solid organ transplant (SOT) group (n = 15; 12 ITX and 3 modified multivisceral transplantation [MMVTX]) and the SOT-AWTX group (n = 14; 12 ITX and 2 MMVTX), with the latter including one ITX-AWTX retransplantation. Two doses of alemtuzumab were used for induction (30 mg, 6 and 24 h after reperfusion), and tacrolimus (trough levels 8-12 ng/mL) was used for maintenance immunosuppression. Patient survival was similar in both groups (67% vs. 61%); however, the SOT-AWTX group showed faster posttransplant recovery, better intestinal graft survival (79% vs. 60%), a lower intestinal rejection rate (7% vs. 27%) and a lower rate of misdiagnoses in which viral infection was mistaken and treated as rejection (14% vs. 33%). The skin component of the AW may serve as an immune modulator and sentinel marker for immunological activity in the host. This can be a vital tool for timely prevention of intestinal graft rejection and, more important, avoidance of overimmunosuppression in cases of bowel dysfunction not related to graft rejection.
Subject(s)
Abdominal Wall/surgery , Graft Rejection/diagnosis , Intestines/transplantation , Postoperative Complications , Short Bowel Syndrome/surgery , Skin Diseases/pathology , Adult , Female , Graft Rejection/etiology , Graft Survival , Humans , Male , Prospective Studies , Short Bowel Syndrome/complications , Skin Diseases/etiology , Treatment OutcomeABSTRACT
Acute cellular rejection occurs frequently during the first few weeks following liver transplantation. During this period, its molecular phenotype is confounded by peri- and postoperative proinflammatory events. To unambiguously define the molecular profile associated with rejection, we collected sequential biological specimens from 55 patients at least 3 years after liver transplantation who developed rejection during trials of intentional immunosuppression withdrawal. We analyzed liver tissue and blood samples obtained before initiation of drug withdrawal and at rejection, alongside blood samples collected during the weaning process. Gene expression profiling was conducted using whole-genome microarrays and real-time polymerase chain reaction. Rejection resulted in distinct blood and liver tissue transcriptional changes in patients who were either positive or negative for hepatitis C virus (HCV). Gene expression changes were mostly independent from pharmacological immunosuppression, and their magnitude correlated with severity of histological damage. Differential expression of a subset of genes overlapped across all conditions. These were used to define a blood predictive model that accurately identified rejection in HCV-negative, but not HCV-positive, patients. Changes were detectable 1-2 mo before rejection was diagnosed. Our results provide insight into the molecular processes underlying acute cellular rejection in liver transplantation and help clarify the potential utility and limitations of transcriptional biomarkers in this setting.
Subject(s)
Biomarkers/metabolism , Gene Expression Profiling , Graft Rejection/diagnosis , Immune Tolerance/genetics , Liver Transplantation , Postoperative Complications , Withholding Treatment , Female , Follow-Up Studies , Gene Expression Regulation , Graft Rejection/etiology , Graft Rejection/metabolism , Graft Survival , Humans , Immunosuppression Therapy , Immunosuppressive Agents/therapeutic use , Liver Diseases/surgery , Male , Middle Aged , Prospective StudiesABSTRACT
Adoptive immunotherapy with regulatory T cells (Treg) is a new option to promote immune tolerance following solid organ transplantation (SOT). However, Treg from elderly patients awaiting transplantation are dominated by the CD45RA(-) CD62L(+) central memory type Treg subset (TregCM), and the yield of well-characterized and stable naïve Treg (TregN) is low. It is, therefore, important to determine whether these TregCM are derived from the thymus and express high stability, suppressive capacity and a broad antigen repertoire like TregN. In this study, we showed that TregCM use a different T cell receptor (TCR) repertoire from conventional T cells (Tconv), using next-generation sequencing of all 24 Vß families, with an average depth of 534 677 sequences. This showed almost no contamination with induced Treg. Furthermore, TregCM showed enhanced suppressive activity on Tconv at early checkpoints of immune activation controlling activation markers expression and cytokine secretion, but comparable inhibition of proliferation. Following in vitro expansion under mTOR inhibition, TregCM expanded equally as well as TregN without losing their function. Despite relatively limited TCR repertoire, TregCM also showed specific alloresponse, although slightly reduced compared to TregN. These results support the therapeutic usefulness of manufacturing Treg products from CD45RA(-) CD62L(+) Treg-enriched starting material to be applied for adoptive Treg therapy.
Subject(s)
T-Lymphocytes, Regulatory/immunology , Adult , Age Factors , Aged , Aged, 80 and over , Biomarkers/metabolism , Cytokines/metabolism , Flow Cytometry , Forkhead Transcription Factors/metabolism , Healthy Volunteers , Humans , Kidney Transplantation , Leukocyte Common Antigens/metabolism , Middle Aged , Receptors, Antigen, T-Cell/metabolism , T-Lymphocytes, Regulatory/metabolism , Thymus Gland/cytology , Thymus Gland/immunologyABSTRACT
Primary T cell activation and effector cell differentiation is required for rejection of allogeneic grafts in naïve recipients. It has become evident, that mitochondria play an important role for T cell activation. Expression of several mitochondrial proteins such as TCAIM (T cell activation inhibitor, mitochondrial) is down-regulated upon T cell receptor triggering. Here we report that TCAIM inhibited spontaneous development of memory and effector T cells. CD4(+) T cells from Tcaim knock-in (KI) mice showed reduced activation, cytokine secretion and proliferation in vitro. Tcaim KI T cells tolerated allogeneic skin grafts upon transfer into Rag-1 KO mice. CD4(+) and CD8(+) T cells from these mice did not infiltrate skin grafts and kept a naïve or central memory phenotype, respectively. They were unable to acquire effector phenotype and functions. TCAIM altered T cell activation-induced mitochondrial distribution and reduced mitochondrial reactive oxygen species (mROS) production. Thus, TCAIM controls T cell activation and promotes tolerance induction probably by regulating TCR-mediated mitochondrial distribution and mROS production.
Subject(s)
Lymphocyte Activation/immunology , Mitochondria/immunology , Mitochondrial Proteins/physiology , Skin Transplantation , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes/immunology , Transplantation Tolerance/immunology , Animals , Cell Differentiation , Cells, Cultured , Cytokines/metabolism , Flow Cytometry , Homeodomain Proteins/physiology , Immunologic Memory/immunology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout , Mitochondria/metabolism , Reactive Oxygen Species/metabolism , T-Lymphocytes/metabolism , Transplantation, HomologousABSTRACT
Malignancy is an important cause of death in transplant recipients. Cutaneous squamous cell carcinoma (cSCC) causes significant morbidity and mortality as 30% of transplant recipients will develop cSCC within 10 years of transplantation. Previously we have shown that high numbers of regulatory T cells (Tregs) are associated with the development of cSCC in kidney transplant recipients (KTRs). Demethylation analysis of the Treg-specific demethylated region (TSDR) provides a more accurate association with cSCC risk after transplantation. Age, gender and duration of immunosuppression matched KTRs with (n=32) and without (n=27) cSCC, were re-analyzed for putative clinical and immunological markers of cancer risk. The proportion of FOXP3+ CD4+ cells was higher in the population with a previous SCC. Major T cell subsets remained stable over time; although B cell, CD8 and CD4 subpopulations demonstrated age-related changes. TSDR methylation analysis allowed clarification of Treg numbers, enhancing the association of high Treg levels in KTRs with cSCC compared to the cSCC-free cohort. These data validate and expand on previous findings in long-term KTRs, and show that immune markers remain stable over time. TSDR demethylation analysis provides a more accurate biomarker of cancer posttransplantation.
Subject(s)
Biomarkers, Tumor/blood , Carcinoma, Squamous Cell/blood , DNA Methylation , Transplantation/adverse effects , Adult , Aged , Aged, 80 and over , Female , Humans , Immunosuppressive Agents/administration & dosage , Male , Middle AgedABSTRACT
Foxp3(+) regulatory T cells (Treg) have a central role for keeping the balance between pro- and anti-inflammatory immune responses against chronically encountered antigens at mucosal sites. However, their antigen specificity especially in humans is largely unknown. Here we used a sensitive enrichment technology for antigen-reactive T cells to directly compare the conventional vs. regulatory CD4(+) T-cell response directed against two ubiquitous mucosal fungi, Aspergillus fumigatus and Candida albicans. In healthy humans, fungus-specific CD4(+)CD25(+)CD127(-)Foxp3(+) Treg are strongly expanded in peripheral blood and possess phenotypic, epigenetic and functional features of thymus-derived Treg. Intriguingly, for A. fumigatus, the strong Treg response contrasts with minimal conventional T-cell memory, indicating selective Treg expansion as an effective mechanism to prevent inappropriate immune activation in healthy individuals. By contrast, in subjects with A. fumigatus allergies, specific Th2 cells were strongly expanded despite the presence of specific Treg. Taken together, we demonstrate a largely expanded Treg population specific for mucosal fungi as part of the physiological human T-cell repertoire and identify a unique capacity of A. fumigatus to selectively generate Treg responses as a potentially important mechanism for the prevention of allergic reactions.
Subject(s)
Antigens, Fungal/immunology , Epitopes, T-Lymphocyte/immunology , Fungi/immunology , Immune Tolerance , Mucous Membrane/immunology , Mucous Membrane/microbiology , T-Lymphocytes, Regulatory/immunology , Aspergillus/immunology , Cells, Cultured , Cystic Fibrosis/complications , Cystic Fibrosis/immunology , Humans , Hypersensitivity/etiology , Immunologic Memory , Immunophenotyping , Lymphocyte Count , Phenotype , T-Lymphocytes, Regulatory/metabolism , Tumor Necrosis Factor Receptor Superfamily, Member 9/metabolismABSTRACT
To ensure safety tolerance induction protocols are accompanied by conventional immunosuppressive drugs (IS). But IS such as calcineurin inhibitors (CNI), for example, cyclosporin A (CsA), can interfere with tolerance induction. We investigated the effect of an additional transient CsA treatment on anti-CD4mAb-induced tolerance induction upon rat kidney transplantation. Additional CsA treatment induced deteriorated graft function, resulting in chronic rejection characterized by glomerulosclerosis, interstitial fibrosis, tubular atrophy and vascular changes. Microarray analysis revealed enhanced intragraft expression of the B cell attracting chemokine CXCL13 early during CsA treatment. Increase in CXCL13 expression is accompanied by enhanced B cell infiltration with local and systemic IgG production and C3d deposition as early as 5 days upon CsA withdrawal. Adding different CNIs to cultures of primary mesangial cells isolated from glomeruli resulted in a concentration-dependent increase in CXCL13 transcription. CsA in synergy with TNF-α can enhance the B cell attracting and activating potential of mesangial cells. Transient B cell depletion or transfer of splenocytes from tolerant recipients 3 weeks after transplantation could rescue tolerance induction and did inhibit intragraft B cell accumulation, alloantibody production and ameliorate chronic rejection.
Subject(s)
Antibodies, Monoclonal/pharmacology , CD4-Positive T-Lymphocytes/immunology , Calcineurin Inhibitors , Immune Tolerance/immunology , Immunosuppressive Agents/pharmacology , Kidney Transplantation , Animals , B-Lymphocytes/immunology , Calcineurin/pharmacology , Chemokine CXCL13/biosynthesis , Cyclosporine/pharmacology , Graft Rejection/drug therapy , Graft Rejection/immunology , Graft Rejection/prevention & control , Humans , Immune Tolerance/drug effects , Kidney/metabolism , Lymphocyte Activation , Male , Rats , Rats, Inbred LewABSTRACT
We previously demonstrated the ability of CD3-specific antibodies (Abs) to induce tolerance of fully mismatched pancreatic islets when administered at the time of effector T-cell priming (day +7). When administered on day -1, CD3 Abs only displayed an immunosuppressive effect with no permanent acceptance. Here we show that rejection correlates with progressive migration of CD4(+) and CD8(+) T cells into the graft. In contrast, the day +7 CD3 Ab tolerogenic effect is associated with absence of de novo accumulation of CD8(+) T cells within the allograft while CD4(+) T-cell migration is not altered. Furthermore, the increased proportion in T-regulatory cells, observed both in the draining lymph nodes and in the transplanted islets, was more pronounced after the delayed (day +7) than the early (day -1) CD3 Ab course. Last, tolerance-promoting (day +7), but not immunosuppressive (day -1) CD3 Ab treatment was associated with an elevated in situ Foxp3/α-1,2-mannosidase gene expression ratio, identified as a biomarker predicting tolerance in renal transplant patients. In conclusion, intragraft-enhanced regulation over effector function after the delayed but not the early CD3 antibody therapy discriminates between the tolerance-promoting and immunosuppressive effect of CD3 Ab treatment and further highlights the importance of the therapeutic window.
Subject(s)
Autoantibodies/immunology , CD3 Complex/immunology , Islets of Langerhans Transplantation , Models, Animal , Animals , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Mice , Mice, Inbred Strains , Real-Time Polymerase Chain Reaction , Transplantation, HomologousSubject(s)
Acute Kidney Injury/genetics , Biomarkers/metabolism , Fibrosis/diagnosis , Glomerulonephritis/diagnosis , Graft Rejection/diagnosis , Inflammation/diagnosis , Kidney Diseases/therapy , Kidney Transplantation/adverse effects , Kidney Transplantation/immunology , T-Lymphocytes/immunology , Female , Humans , MaleABSTRACT
Despite remarkable progress in organ transplantation through the development of a wealth of immunosuppressive drugs highly effective at controlling acute rejection, two major problems still remain, the loss of transplants due to chronic rejection and the growing number of sensitized recipients due to previous transplants, transfusions or pregnancies. Induction of immune tolerance appears to be the only way to curb this complex situation. Here we describe that a therapy, already successfully used to restore immune tolerance to self-antigens in overt autoimmunity, is effective at promoting transplant tolerance. We demonstrate that a short low-dose course with CD3 antibodies started after transplantation, at the time of effector T cell priming to alloantigens, induces permanent acceptance of fully mismatched islet allografts. Mechanistic studies revealed that antigen-specific regulatory and effector T cells are differentially affected by the treatment. CD3 antibody treatment preferentially induces apoptosis of activated alloreactive T cells which is mandatory for tolerance induction. In contrast, regulatory T cells are relatively spared from CD3 antibody-induced depletion and can transfer antigen-specific tolerance thus arguing for their prominent role in sustaining long-term graft survival.
Subject(s)
Antibodies, Monoclonal/pharmacology , CD3 Complex/pharmacology , Immune Tolerance/immunology , Islets of Langerhans/immunology , Transplantation Tolerance/immunology , Animals , Antibodies, Monoclonal/immunology , CD3 Complex/immunology , Cell Transplantation/methods , Disease Models, Animal , Graft Rejection , Graft Survival , Immune Tolerance/drug effects , Isoantigens/immunology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Random Allocation , Real-Time Polymerase Chain Reaction , Risk Factors , Sensitivity and Specificity , Time Factors , Transplantation Immunology/physiology , Transplantation Tolerance/physiologyABSTRACT
Recent data suggest that donor-specific memory T cells (T(mem)) are an independent risk factor for rejection and poor graft function in patients and a major challenge for immunosuppression minimizing strategies. Many tolerance induction protocols successfully proven in small animal models e.g. costimulatory blockade, T cell depletion failed in patients. Consequently, there is a need for more predictive transplant models to evaluate novel promising strategies, such as adoptive transfer of regulatory T cells (Treg). We established a clinically more relevant, life-supporting rat kidney transplant model using a high responder (DA to LEW) recipients that received donor-specific CD4(+)/ 8(+) GFP(+) T(mem) before transplantation to achieve similar pre-transplant frequencies of donor-specific T(mem) as seen in many patients. T cell depletion alone induced long-term graft survival in naïve recipients but could not prevent acute rejection in T(mem)(+) rats, like in patients. Only if T cell depletion was combined with permanent CNI-treatment, the intragraft inflammation, and acute/chronic allograft rejection could be controlled long-term. Remarkably, combining 10 days CNI treatment and adoptive transfer of Tregs (day 3) but not Treg alone also induced long-term graft survival and an intragraft tolerance profile (e.g. high TOAG-1) in T(mem)(+) rats. Our model allows evaluation of novel therapies under clinically relevant conditions.
Subject(s)
Calcineurin Inhibitors , Graft Rejection , Immunosuppressive Agents/pharmacology , Kidney Transplantation , T-Lymphocytes, Regulatory/immunology , Adoptive Transfer , Animals , Flow Cytometry , Immunologic Memory , Lymphocyte Depletion , Rats , Rats, Inbred Lew , Reverse Transcriptase Polymerase Chain ReactionABSTRACT
Despite novel targeted agents, prognosis of metastatic renal cell cancer (RCC) remains poor, and experimental therapeutic strategies are warranted. Transfection of tumor cells with co-stimulatory molecules and/or cytokines is able to increase immunogenicity. Therefore, in our clinical study, 10 human leukocyte antigen (HLA)-A(*)0201(+) patients with histologically-confirmed progressive metastatic clear cell RCC were immunized repetitively over 22 weeks with 2.5-40 × 10(6) interleukin (IL)-7/CD80 cotransfected allogeneic HLA-A(*)0201(+) tumor cells (RCC26/IL-7/CD80). Endpoints of the study were feasibility, safety, immunological and clinical responses. Vaccination was feasible and safe. In all, 50% of the patients showed stable disease throughout the study; the median time to progression was 18 weeks. However, vaccination with allogeneic RCC26/IL-7/CD80 tumor cells was not able to induce TH1-polarized immune responses. A TH2 cytokine profile with increasing amounts of antigen-specific IL-10 secretion was observed in most of the responding patients. Interferon-γ secretion by patient lymphocytes upon antigen-specific and non-specific stimulation was substantially impaired, both before and during vaccination, as compared with healthy controls. This is possibly due to profound tumor-induced immunosuppression, which may prevent induction of antitumor immune responses by the gene-modified vaccine. Vaccination in minimal residual disease with concurrent depletion of regulatory cells might be one strategy to overcome this limitation.
Subject(s)
Cancer Vaccines/therapeutic use , Carcinoma, Renal Cell/therapy , Interleukin-7/immunology , Kidney Neoplasms/therapy , Adult , Aged , B7-1 Antigen/metabolism , Cancer Vaccines/administration & dosage , Cell Line, Tumor , Female , HLA Antigens/analysis , Humans , Male , Middle Aged , T-Lymphocytes/immunology , TransfectionABSTRACT
The frequency of delayed function of kidney transplants varies greatly and is associated with quality of graft, donor age and the duration of cold ischemia time. Furthermore, body weight differences between donor and recipient can affect primary graft function, but the underlying mechanism is poorly understood. We transplanted kidney grafts from commensurate body weight (L-WD) or reduced body weight (H-WD) donor rats into syngeneic or allogeneic recipients. Twenty-four hours posttransplantation, serum creatinine levels in H-WD recipients were significantly higher compared to L-WD recipients indicating impaired primary graft function. This was accompanied by upregulation of IL-6 transcription and increased tubular destruction in grafts from H-WD recipients. Using DNA microarray analysis, we detected decreased expression of genes associated with kidney function and an upregulation of other genes such as Cyp3a13, FosL and Trib3. A single application of IL-6 into L-WD recipients is sufficient to impair primary graft function and cause tubular damage, whereas immediate neutralization of IL-6 receptor signaling in H-WD recipients rescued primary graft function with well-preserved kidney graft architecture and a normalized gene expression profile. These findings have strong clinical implication as anti-IL6R treatment of patients receiving grafts from lower-weight donors could be used to improve primary graft function.
Subject(s)
Body Weight/physiology , Interleukin-6/physiology , Kidney Transplantation/physiology , Signal Transduction/physiology , Animals , Apoptosis/physiology , Creatinine/blood , Heme Oxygenase-1/metabolism , JNK Mitogen-Activated Protein Kinases/metabolism , Kidney Transplantation/pathology , Kidney Tubules/pathology , Male , Models, Animal , Rats , Rats, Inbred Lew , Rats, Inbred StrainsABSTRACT
This prospective randomized pilot study compared the influence of fentanyl-based versus remifentanil-based anaesthesia on cytokine responses and expression of the suppressor of cytokine signalling (SOCS)-3 gene following coronary artery bypass graft surgery. Forty patients were assigned to receive anaesthesia with either intravenous remifentanil (0.3 - 0.6 microg/kg per min; n = 20) or intravenous fentanyl (5 - 10 microg/kg per h; n = 20). Levels of interleukin (IL)-6, IL-10, tumour necrosis factor-alpha and interferon-gamma (IFN-gamma) and the expression of SOCS-3 were measured pre- and post-operatively. The data from 33 of the patients were analysed. The IFN-gamma/IL-10 ratio after concanavalin A stimulation in whole blood cells on post-operative day 1 and SOCS-3 gene expression on post-operative day 2 were significantly lower in the remifentanil group than in the fentanyl group. The time in the intensive care unit was also significantly lower in the remifentanil group. These findings suggest that remifentanil can attenuate the exaggerated inflammatory response that occurs after cardiac surgery with cardiopulmonary bypass. Further clinical trials are required to define the influence of choice of intra-operative opioid on post-operative outcome.
Subject(s)
Anesthetics, Intravenous/pharmacology , Coronary Artery Bypass , Cytokines/blood , Fentanyl/pharmacology , Immunity, Cellular/drug effects , Piperidines/pharmacology , Anesthetics, Intravenous/administration & dosage , Fentanyl/administration & dosage , Gene Expression/drug effects , Humans , Immunity, Cellular/physiology , Interferon-gamma/blood , Interleukins/blood , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/metabolism , Pilot Projects , Piperidines/administration & dosage , Prospective Studies , Remifentanil , Signal Transduction/drug effects , Suppressor of Cytokine Signaling 3 Protein , Suppressor of Cytokine Signaling Proteins/genetics , Suppressor of Cytokine Signaling Proteins/metabolism , Tumor Necrosis Factor-alpha/bloodABSTRACT
Ischemia/reperfusion injury leads to activation of graft endothelial cells (EC), boosting antigraft immunity and impeding tolerance induction. We hypothesized that the complement inhibitor and EC-protectant dextran sulfate (DXS, MW 5000) facilitates long-term graft survival induced by non-depleting anti-CD4 mAb (RIB 5/2). Hearts from DA donor rats were heterotopically transplanted into Lewis recipients treated with RIB 5/2 (20 mg/kg, days-1,0,1,2,3; i.p.) with or without DXS (grafts perfused with 25 mg, recipients treated i.v. with 25 mg/kg on days 1,3 and 12.5 mg/kg on days 5,7,9,11,13,15). Cold graft ischemia time was 20 min or 12 h. Median survival time (MST) was comparable between RIB 5/2 and RIB 5/2+DXS-treated recipients in the 20-min group with >175-day graft survival. In the 12-h group RIB 5/2 only led to chronic rejection (MST = 49.5 days) with elevated alloantibody response, whereas RIB 5/2+DXS induced long-term survival (MST >100 days, p < 0.05) with upregulation of genes related to transplantation tolerance. Analysis of the 12-h group treated with RIB 5/2+DXS at 1-day posttransplantation revealed reduced EC activation, complement deposition and inflammatory cell infiltration. In summary, DXS attenuates I/R-induced acute graft injury and facilitates long-term survival in this clinically relevant transplant model.
Subject(s)
Antibodies, Monoclonal/therapeutic use , Dextran Sulfate/therapeutic use , Graft Survival/drug effects , Heart Transplantation , Immunologic Factors/therapeutic use , Reperfusion Injury/immunology , Animals , Antibodies, Monoclonal/immunology , CD4 Antigens , CD4-Positive T-Lymphocytes , Cold Ischemia/adverse effects , Disease Models, Animal , Graft Survival/immunology , Immunity, Innate , Male , Rats , Rats, Inbred Strains , Reperfusion Injury/etiology , Transplantation Tolerance/drug effects , Transplantation Tolerance/immunology , Transplantation, HomologousABSTRACT
The clinical success of new treatment strategies aiming on inducing permanent graft acceptance will rely on the ability to determine whether specific unresponsiveness to donor alloantigens has developed and for how long it is maintained. To identify markers for such posttransplant monitoring, genes differentially expressed by graft infiltrating leukocytes during tolerance induction or rejection after kidney transplantation in rats were compared. A subsequently performed full kinetic analysis in two different transplant models, kidney and heart, in two species, rat and mouse identified two markers (TOAG-1, alpha-1,2-mannosidase) with high specificity and reproducibility, which are highly expressed during induction and maintenance of acceptance, and downregulated during rejection. Expression level of these markers showed a strong positive correlation with graft function. In addition, expression of both genes was downregulated in the peripheral blood and the graft prior to rejection, suggesting that these markers may be useful for monitoring in clinical transplantation where peripheral blood is the most easily accessible patient sample. Interestingly, downregulation of TOAG-1 and alpha-1,2-mannosidase expression occurred in graft infiltrating cells and expression of both genes was also downregulated after T-cell activation in vitro.