Rejection In Recipients Research Articles

Multiple-biomarkers provide powerful prediction of early acute renal allograft rejection by combination of serum fractalkine, IFN-γ and IP-10

Biomarkers are urgently required for predicting rejection so that anti-rejection treatment can be taken early to protect the allograft from irreversible damage. We hypothesized that the combination of circulating fractalkine, IFN-γ and IP-10 might serve as effective biomarkers for predicting early acute renal allograft rejection. We conducted a retrospective study of 87 subjects, who were classified into acute rejection group (ARG; n = 38) and non-rejection group (NRG; n = 49). Serum fractalkine, IFN-γ and IP-10 levels were measured by Luminex. The levels of fractalkine on day 0 and 7th day, IP-10 on 4th and 7th day, and IFN-γ on 7th day in ARG was significantly higher than that in NRG. Kaplan–Meier survival analysis highlighted the higher-levels groups of fractalkine on day 0, 4th and 7th day, IFN-γ on day 0, 1st, 4th, and 7th day and IP-10 on the 4th and 7th day in rejection-free survival probability were significantly lower than low-levels groups. ROC analyses highlight the superiority of fractalkine on day 0, IP-10 on day 0, 4th and 7th day, and IFN-γ on day 0, 1st and 7th day in prediction of acute rejection. We found the combination of fractalkine on day 0, IP-10 on 7th day and IFN-γ on 7th day had the highest AUC (0.866) for predicting rejection with a sensitivity of 86.8% and a specificity of 89.8%. Our findings demonstrated a more powerful prediction of early acute renal allograft rejection during the first month after transplantation by combination of multiple-biomarkers of fractalkine, IFN-γ and IP-10, and the results might help stratify the immunologic risk of acute allograft rejection in recipients.

Inflammatory Responses in α1,3-Galactosyltransferase Gene-Knockout (GTKO) Porcine Vascular Retransplantation to Cynomolgus Monkeys

Introduction Various pro-inflammatory factors are produced in response to a xenograft. However, it is poorly understood the differences of inflammatory responses by preformed anti-pig antibodies. In this study, we developed the animal model of xenogeneic antibody-mediated rejection of vascular xenografts in sensitized recipients and examined the systemic inflammatory responses. Methods Cynomolgus monkeys (2.5 ~ 4 kg, n=4) received femoral artery grafts from GTKO pig. Immunosuppressive therapy was based on costimulation blockade using anti-CD154 mAb (20 mg/kg). They also received cobra venom factor (0.05 mg/kg), steroid, and tacrolimus. In addition to that, two monkeys received anti-thymocyte globulin (ATG, 20 mg/kg) to minimize T-cell-mediated rejection while allowing the development of donor-specific antibodies. Immunosuppression have been stopped at the time of graft removal (n=4, day 24, 28 or 32). Same immunosuppression protocol was applied for the second vascular transplantation. Whole blood and serum samples were obtained from recipients before and serially after vascular transplantation. They were tested C-reactive protein (C-RP), pro-inflammatory cytokines and chemokines, and blood cell count. In addition, expression of tissue factor (TF) on the transplanted artery was analyzed by immunofluorescence assay. Results In vascular xenograft recipients, significantly high levels of C-RP were detected in first and second vascular recipients in comparison with before transplantation. The levels of IL-6 and TNF-α were not significantly higher after first vascular transplantation. However, MCP-1 and IL-8 levels were increased after first vascular transplantation. In second xenograft recipients, the level of IL-6, MCP-1, and IL-8 were increased after transplantation, but not TNF-α. Absolute numbers of monocytes and neutrophils were elevated after transplantation. Additionally, peripheral blood leukocytes were increased in the group that ATG was not given after transplantation. TF expressions were increased on the second transplanted artery compare to first transplanted artery. Conclusion We have developed a model of xenogeneic antibody-mediated rejection in recipients with preformed anti-pig antibodies. The porcine vascular transplantation to Cynomolgus model showed more severe inflammation in second transplanted recipients compare to first transplanted recipients. It means that sensitization to porcine antigens is increased in the vascular retransplanted recipients. This study was supported by the Ministry of Science, ICT & Future Planning (#2014M3A9D3034034).

Decreased Incidence of Acute Cellular Rejection in Low-Muscle-Mass Recipients After Living-donor Liver Transplantation

BackgroundSarcopenia has recently been studied as a potential risk factor for mortality and complications after liver transplantation. We investigated the impact of low muscle mass on postoperative outcomes after living-donor liver transplantation. MethodsOur study population consisted of 100 adult recipients who underwent living-donor liver transplantation in our department between 2005 and 2017. Recipients were divided into a low-muscle-mass group (L group) and a normal-muscle-mass group (N group) based on skeletal muscle index (SMI) values, and postoperative outcomes were compared between the groups. Regarding factors that were significantly different between the groups, multivariate analyses were performed to identify predictive factors. ResultsBased on the SMI definition, 47 and 53 of the recipients were categorized as having low muscle mass (L group) and normal muscle mass (N group), respectively. Comparison between the groups revealed a significantly reduced incidence of rejection (10.6% in L group vs 30.2% in N group, P = .017) and increased incidences of bacterial infection (61.7% in L group vs 37.7% in N group, P = .017) in the L group compared with the N group. The survival rate did not differ significantly between the groups. Multivariate analyses indicated that muscle mass was a significant predictive factor for both rejection and bacterial infection. ConclusionIt is important to recognize that muscle mass has an impact not only on bacterial infection but also on rejection in recipients with low muscle mass in the postoperative course of living-donor liver transplantation.

Outcomes of EC-MPS combined with low-dose tacrolimus in DCD kidney transplantation for high-risk DGF recipients

Effective use of immunosuppressive agents to avoid the occurrence of nephrotoxicity and rejection in recipients with delayed graft function (DGF) is a concern for physicians. We investigated the outcomes of treatment with enteric-coated mycophenolate sodium (EC-MPS) in combination with a low-dose of tacrolimus (Tac) in renal transplantation for recipients with a high risk of DGF. We conducted a retrospective study of 61 recipients with a high risk of DGF who were treated with EC-MPS and low-dose Tac. The recipients were separated into a no-DGF group and a DGF group, based on whether DGF actually occurred. The results showed that although EC-MPS and Tac doses were similar in both groups, the percentage of recipients whose mycophenolic acid area under the curve 0–12 h (MPA-AUC0–12 h) was below 30 (mg·h)/L was significantly higher and the Tac trough concentration significantly lower in the DGF group one week after transplantation. Notably, a higher incidence of biopsy-proven acute rejection (BPAR) was found in the DGF group and among all recipients whose MPA-AUC0–12 h was less than 30 (mg·h)/L at one week after transplantation. One-year graft survival, patient survival, allograft function, and the incidence of the most common adverse events were similar in the two groups. In conclusion, the immunosuppressive regime is applicable to Chinese kidney transplant recipients, and early low exposure to EC-MPS was related to acute rejection in the recipients at a high risk of DGF.

Immunosuppressive effect of arsenic trioxide on islet xenotransplantation prolongs xenograft survival in mice

The role of arsenic trioxide (As2O3) in inhibiting immune rejection and prolonging islet allograft survival has been identified in islet allotransplantation. This study aims to explore the role of As2O3 in islet xenotransplantation and the action mechanism. The streptozotocin (STZ) was used in C57BL/6 mice to induce the type 1 diabetes mellitus (T1DM) for xenotransplantation models establishment. Donor islets were isolated by digesting. The flow cytometry (FCM) was used to analyze lymphocyte types. The blood sugar level was detected by using intraperitoneal glucose tolerance test (IPGTT). The serum level of cytokines was determined by the enzyme-linked immunosorbent assay (ELIZA). The cell proliferation was measured by MTT assay. The mRNA levels were quantified with qRT-PCR. As2O3 prolonged the survival of the recipient mice but had no influence on body weight. As2O3 protected the function of xenograft in insulin secretion and suppressed immune rejection of recipient. As2O3 inhibited proliferation of T lymphocyte and increased the proportion of Foxp3+ regulatory T cells in recipient mice. As2O3 inhibited activation and promoted clonal anergy of T lymphocyte. As2O3 decreased total number of B cells and reduced partial antibody levels in recipient mice. As2O3 and leflunomide showed a synergistic effect in suppressing islet xenotransplant rejection. As2O3 prolongs islet xenograft survival by inhibiting cellular immune response, and increasing Foxp3+ regulatory T cells, while decreasing partial antibody levels in serum.

Bioengineered Lungs: A Challenge and An Opportunity

Lung biofabrication is a new tissue engineering and regenerative development aimed at providing organs for potential use in transplantation. Lung biofabrication is based on seeding cells into an acellular organ scaffold and on culturing them in an especial purpose bioreactor. The acellular lung scaffold is obtained by decellularizing a non-transplantable donor lung by means of conventional procedures based on application of physical, enzymatic and detergent agents. To avoid immune recipient's rejection of the transplanted bioengineered lung, autologous bone marrow/adipose tissue-derived mesenchymal stem cells, lung progenitor cells or induced pluripotent stem cells are used for biofabricating the bioengineered lung. The bioreactor applies circulatory perfusion and mechanical ventilation with physiological parameters to the lung during biofabrication. These physical stimuli to the organ are translated into the stem cell local microenvironment – e.g. shear stress and cyclic stretch – so that cells sense the physiological conditions in normally functioning mature lungs. After seminal proof of concept in a rodent model was published in 2010, the hypothesis that lungs can be biofabricated is accepted and intense research efforts are being devoted to the topic. The current experimental evidence obtained so far in animal tests and in ex vivo human bioengineered lungs suggests that the date of first clinical tests, although not immediate, is coming. Lung bioengineering is a disrupting concept that poses a challenge for improving our basic science knowledge and is also an opportunity for facilitating lung transplantation in future clinical translation.

Bioengineered Lungs: A Challenge and An Opportunity

Lung biofabrication is a new tissue engineering and regenerative development aimed at providing organs for potential use in transplantation. Lung biofabrication is based on seeding cells into an acellular organ scaffold and on culturing them in an especial purpose bioreactor. The acellular lung scaffold is obtained by decellularizing a non-transplantable donor lung by means of conventional procedures based on application of physical, enzymatic and detergent agents. To avoid immune recipient's rejection of the transplanted bioengineered lung, autologous bone marrow/adipose tissue-derived mesenchymal stem cells, lung progenitor cells or induced pluripotent stem cells are used for biofabricating the bioengineered lung. The bioreactor applies circulatory perfusion and mechanical ventilation with physiological parameters to the lung during biofabrication. These physical stimuli to the organ are translated into the stem cell local microenvironment – e.g. shear stress and cyclic stretch – so that cells sense the physiological conditions in normally functioning mature lungs. After seminal proof of concept in a rodent model was published in 2010, the hypothesis that lungs can be biofabricated is accepted and intense research efforts are being devoted to the topic. The current experimental evidence obtained so far in animal tests and in ex vivo human bioengineered lungs suggests that the date of first clinical tests, although not immediate, is coming. Lung bioengineering is a disrupting concept that poses a challenge for improving our basic science knowledge and is also an opportunity for facilitating lung transplantation in future clinical translation.

A Novel Rhinoplasty Sculpture Technique Using Ancient Chinese Architectural Technology.

Rhinoplasty is one of the most delicate procedures in plastic and reconstructive surgery. Precision in every millimeter is vital in ensuring a better quality of surgical outcome. Many methods have been developed to fulfill this requirement. One such method is an implant, whether autogenous or artificial. Artificial implants involve several surgical complications, such as recipient rejection of implant material, infections, and rigid feel of the nasal tip. Hence, autogenous implants were eventually more widely applied, with material being obtained from the septum, concha, or rib cartilages. Therefore, the authors developed a new technique of rhinoplasty, using the osteochondral rib as an autogenous implant based on the ancient Chinese architectural technology called the DouGong method. The authors hereby present the results of 288 patients treated in our faculty wherein the data from the patients and the preoperative and postoperative 3-dimensional computed tomography scans were processed using Mimics software. The uniqueness of these implants is that the joint between the nasal dorsum and the columella strut is fixated without any screw, stitches, or K-wire. This procedure proved to be very useful as this technique not only minimized the application of fixation techniques, but also helped achieve a better nasofrontal angle, nasolabial angle, and columella length. After monitoring follow-ups of our patients, the authors hereby propose the use of this DouGong-based novel technique to improve the overall quality and outcome of corrective rhinoplasty.

A Model of Acute Antibody-Mediated Renal Allograft Rejection in the Sensitized Rata.

Antibody-mediated rejection in transplant recipients with preexisting donor-specific antibodies is a challenging clinical situation. However, we lack suitable animal models to study this scenario. The aim of this study was to develop an animal model of acute antibody-mediated rejection of renal allografts in sensitized recipients. We used major histocompatibility complex class I and II incompatible rat strains (Dark Agouti RT1av1 and Lewis RT1l), which develop aggressive rejection. Recipient Lewis rats were immunized with donor strain spleen cells 5 days before surgery to induce donor-specific antibodies. Rats underwent bilateral nephrectomy and orthotopic transplant of the donor kidney. To minimize T-cell-mediated rejection while allowing the development of donor-specific antibodies, recipient animals were given tacrolimus starting the day before surgery. Hyperacute rejection was not seen, but acute graft dysfunction was evident on day 1 with a rapid deterioration of graft function by day 3. Histologic damage featured glomerulopathy, capillaritis, capillary thrombosis, and acute tubular injury. Recipients exhibited high serum levels of donor-specific antibodies and deposition of immunoglobulin G and C4d on graft endothelium. Immunostaining showed substantial endothelial damage, fibrin deposition in glomerular and peritubular capillaries, and infiltrates of macrophages, neutrophils, and natural killer cells. T-cell activation was efficiently suppressed by tacrolimus. We have developed a clinically relevant model of acute antibody-mediated rejection in recipients with preexisting donor-specific antibodies, which is suitable for testing novel therapies.

Outcome of Pretransplantation Therapeutic Plasma Exchange in Highly Sensitized Deceased-donor Kidney Transplant Recipients

BackgroundSensitization is associated with a high rate of post-transplantation rejection. A desensitization protocol using therapeutic plasma exchange (TPE) was proposed to reduce anti-HLA antibody before transplantation, but there has been limited data regarding the efficacy of pretransplantation TPE in highly sensitized deceased-donor kidney transplantation (DDKT). MethodsA retrospective cohort study of 142 patients who received DDKT was conducted and divided into two groups: a high–panel-reactive antibody (PRA) >50% group and a low-PRA ≤50% group. The high-PRA group was sub-divided into those who received and did not receive pretransplantation TPE. Donor-specific anti-HLA antibodies (DSA) were also collected pretransplantation in the high-PRA group. ResultsThe probability of acute rejection was 26, 4, and 9 cases/1000/person month in the high-PRA group with no TPE, the high-PRA group receiving TPE, and the low-PRA group, respectively (P = .0208). In the multivariable logistic regression analysis, the hazard ratio for graft rejection was 2.37 (95% confidence interval: 0.89 to 6.35) and 2.22 (95% confidence interval: 0.54 to 9.13) in the group of high-PRA who received TPE and high-PRA with no TPE, compared with the low-PRA group, respectively (P value not significant). The incidence of antibody-mediated rejection in 6 months in the DSA-positive subgroup was not different between those who received TPE or no TPE. ConclusionDesensitization with TPE is a reasonable alternative for highly sensitized DDKT. Patients who received pretransplantation TPE had a lower incidence of acute rejection compared to the group that did not receive TPE. However, pretransplantation TPE alone was not effective in the prevention of acute rejection in recipients with DSA.

Development of immune response to tissue-restricted self-antigens in simultaneous kidney-pancreas transplant recipients with acute rejection.

Simultaneous kidney-pancreas transplantation (SKP Tx) is a treatment for end-stage kidney disease secondary to diabetes mellitus. We investigated the role of immune responses to donor human leukocyte antigens (HLA) and tissue-restricted kidney and pancreas self-antigens (KSAgs and PSAgs, respectively) in SKP Tx recipients (SKP TxRs). Sera collected from 39 SKP TxRs were used to determine de novo Abs specific for KSAgs (collagen-IV, Col-IV; fibronectin, FN) and PSAgs (insulin, islet cells, glutamic acid decarboxylase, and pancreas-associated protein-1) by ELISA. KSAg-specific IFN-γ, IL-17, and IL-10 cytokines were enumerated by ELISpot. Abs to donor HLA classes I and II were determined by Luminex assay. Abs to KSAgs and PSAgs were detectable in recipients with rejection compared with stable recipients (P<.05). Kidney-only rejection recipients had increased Abs against KSAgs compared with stable (P<.05), with no increase in Abs against PSAgs. Pancreas-only rejection recipients showed increased Abs against PSAgs compared to stable (P<.05), with no Abs against KSAgs. SKP TxRs with rejection showed increased frequencies of KSAg-specific IFN-γ and IL-17 with reduction in IL-10-secreting cells. SKP TxRs with rejection developed Abs to KSAgs and PSAgs demonstrated increased frequencies of kidney or pancreas SAg-specific IFN-γ and IL-17-secreting cells with reduced IL-10, suggesting loss of peripheral tolerance to SAgs.

Influenza: Epidemiology, Laboratory Diagnosis, and Clinics

Influenza is an infectious disease which causes significant morbidity and mortality. Complications of the disease are bronchitis, pneumonia, otitis media, rejection in recipients of transplantation, myocarditis, pericarditis, myositis, glomerulonephritis, and exacerbation of underlying disease such as asthma, chronic obstructive lung disease, and chronic renal failure. Some complications may be seen in high-risk groups. The early diagnosis of the infection and prompt initiation of specific therapy is important for individuals and public health. In this review, we aimed to overview the clinical and epidemiological importance of influenza infections and to give up-to-date information about laboratory diagnosis method.

OR19 Quantification of peripheral B-cell subsets in acute allograft rejection in recipients with renal transplantation

To monitor B cell subsets in peripheral circulation to find a distinctive phenotypic signature of rejection in our cohort. The study population consisted of 211 consecutive first renal allograft recipients who were followed up for 12 months post-transplant. One ml of EDTA peripheral venous blood was collected pre- transplant, 1 month, 3 months, 6 months, 12 months post-transplant and at the time of graft rejection. A multicolour flowcytometry was performed to monitor the percentage of peripheral Plasma cells (CD20-CD38+CD138+), Total B-cells (CD20+), Naïve B-cells (CD20+CD27-CD38-), Activated B-cells (CD20+CD38+CD138-) and Memory B-cells (CD20+CD138-CD27+). Of 211 cases of first kidney allograft recipients, 35 (16.58%) recipients had 38 episodes of acute allograft rejection. Percentage of activated B cells and Memory B-cells were found to be significantly higher in uremic patients (n = 78) than those of healthy persons (n = 40) (20.81 ± 0.7616 % vs. 14.37 ± 0.5972%, p < 0.0001 and 10.56 ± 0.5813% vs 7.658 ± 0.6626%, p = 0.0025 respectively). On the contrary, the percentage of naïve B- cells was found to be significantly lower in the patients than normal controls (61.04 ± 1.691% vs 73.62 ± 1.320%, p < 0.0001). Acute rejection episodes (n = 38) were associated with increase in peripheral percentage of total B-cells (19.02 ± 1.457 vs. 10.80 ± 0.6338, P < 0.0001) and activated B-cells (33.92 ± 1.756 vs. 23.26 ± 1.113, P < 0.0001). On the contrary, the percentage of plasma cells and memory B-cells and naïve B- cells was significantly lower during rejection episodes (0.7447 ± 0.09 vs. 2.363 ± 0.1529, P < 0.0001, 5.871 ± 0.6677 vs. 12.12 ± 0.6584, P < 0.0001 and 44.53 ± 2.504 vs. 52.61 ± 2.488, P = 0.0311 respectively). The percentage of activated B-cells and Memory B-cells were persistently high in uremic patients suggesting that these patients are always in a stage of immune activation. Acute rejection episodes were associated with increased percentage of activated B-cells but decrease in the percentage of plasma- and memory-B cells in the peripheral blood. Therefore, post- transplantation, periodic measurements of B-cell subsets may serve as an important marker in the prediction of acute allograft rejection.

HLA-DQ Mismatches and Rejection in Kidney Transplant Recipients.

The current allocation algorithm for deceased donor kidney transplantation takes into consideration HLA mismatches at the ABDR loci but not HLA mismatches at other loci, including HLA-DQ. However, the independent effects of incompatibilities for the closely linked HLA-DQ antigens in the context of HLA-DR antigen matched and mismatched allografts are uncertain. We aimed to determine the effect of HLA-DQ mismatches on renal allograft outcomes. Using data from the Australia and New Zealand Dialysis and Transplant Registry, we examined the association between HLA-DQ mismatches and acute rejections in primary live and deceased donor kidney transplant recipients between 2004 and 2012 using adjusted Cox regression models. Of the 788 recipients followed for a median of 2.8 years (resulting in 2891 person-years), 321 (40.7%) and 467 (59.3%) received zero and one or two HLA-DQ mismatched kidneys, respectively. Compared with recipients who have received zero HLA-DQ mismatched kidneys, those who have received one or two HLA-DQ mismatched kidneys experienced greater numbers of any rejection (50 of 321 versus 117 of 467; P<0.01), late rejections (occurring >6 months post-transplant; 8 of 321 versus 27 of 467; P=0.03), and antibody-mediated rejections (AMRs; 12 of 321 versus 38 of 467; P=0.01). Compared with recipients of zero HLA-DQ mismatched kidneys, the adjusted hazard ratios for any and late rejections in recipients who had received one or two HLA-DQ mismatched kidneys were 1.54 (95% confidence interval [95% CI], 1.08 to 2.19) and 2.85 (95% CI, 1.05 to 7.75), respectively. HLA-DR was an effect modifier between HLA-DQ mismatches and AMR (P value for interaction =0.02), such that the association between HLA-DQ mismatches and AMR was statistically significant in those who have received one or two HLA-DR mismatched kidneys, with adjusted hazard ratio of 2.50 (95% CI, 1.05 to 5.94). HLA-DQ mismatches are associated with acute rejection, independent of HLA-ABDR mismatches and initial immunosuppression. Clinicians should be aware of the potential importance of HLA-DQ matching in the assessment of immunologic risk in kidney transplant recipients.

Evaluation of Immune Profiles and MicroRNA Expression Profiles in Peripheral Blood Mononuclear Cells of Long-Term Stable Liver Transplant Recipients and Recipients With Acute Rejection Episodes

ObjectiveThis study aimed to document the difference of immunophenotypes in peripheral blood mononuclear cells (PBMCs) between long-term stable liver transplant recipients and recipients with acute rejection. We also sought to identify whether there is any correlation between microRNA (miRNA) expression profile and the differential immunoprofile in these 2 groups to establish a specific miRNA biomarker to identify potential liver transplant recipients. MethodsPBMCs were isolated from 53 stable liver transplant recipients (STA group) and 15 liver transplant recipients with repeated biopsy-proven rejection episodes admitted to our hospital. Immunoprofiles were analyzed by means of flow cytometry. Analysis of miRNA expression in the PBMCs was performed by means of real-time polymerase chain reaction. ResultsThe immune profiling analysis showed increased frequency of peripheral natural killer cells and regulatory T cells in stable liver transplant recipients compared with the acute rejection recipients and healthy volunteers (P < .05). There was no significant difference in the immune cell levels (CD19+ B cells, CD4+ T cells, and CD8+ T cells) in PBMCs among the transplant recipient groups and healthy control subjects. Three miRNAs, miR-18b, miR-340, and miR-106b, were up-regulated in the PBMCs of the STA recipients compared with recipients with acute rejection. ConclusionsThese results suggest that miR-18b, miR-340, and miR-106b, which regulate the expression of specific immunophenotypes, can be used as potential biomarkers to identify long-term stable liver transplant recipients from recipients with acute rejection.

Th-17 Alloimmune Responses in Renal Allograft Biopsies From Recipients of Kidney Transplants Using Extended Criteria Donors During Acute T Cell–Mediated Rejection

Although renal transplantation using expanded criteria donors has become a common practice, immune responses related to immunosenescence in those kidney allografts have not been studied yet in humans. We performed a retrospective molecular analysis of the T cell immune response in 43 kidney biopsies from patients with acute T cell-mediated rejection including 25 from recipients engrafted with a kidney from expanded criteria donor and 18 from recipients grafted with optimal kidney allograft. The clinical, transplant and acute T cell-mediated rejection characteristics of both groups were similar at baseline. The expression of RORγt, Il-17 and T-bet mRNA was significantly higher in the elderly than in the optimal group (p = 0.02, p = 0.036, and p = 0.01, respectively). Foxp3 mRNA levels were significantly higher in elderly patients experiencing successful acute T cell-mediated rejection reversal (p = 0.03). The presence of IL-17 mRNA was strongly associated with nonsuccessful reversal in elderly patients (p = 0.008). Patients with mRNA IL17 expression detection and low mRNA Foxp3 expression experienced significantly more treatment failure (87.5%) than patients with no mRNA IL17 expression and/or high mRNA Foxp3 expression (26.7%; p = 0.017). Our study suggests that the Th17 pathway is involved in pathogenesis and prognosis of acute T cell-mediated rejection in recipients of expanded criteria allograft.

Dysregulated MicroRNA Expression and Chronic Lung Allograft Rejection in Recipients With Antibodies to Donor HLA

The pathogenesis of chronic rejection, Bronchiolitis Obliterans Syndrome (BOS) following lung transplantation (LT) is poorly understood. We hypothesized that development of antibodies to HLA (DSA) is associated with dysregulation of microRNA (miRNA) that predisposes BOS. Towards this, miRNA profiling of mononuclear cells from 10 stable LT (DSA(-) BOS(-) ), 10 LT with DSA(+) BOS(-) (DSA group) and 10 LT with DSA(+) BOS(+) (BOS group) were performed. Prediction by mirPath indicated that differential miRNAs in DSA(+) BOS(-) compared to stable are significantly up-regulated (relative fold >2, p < 0.05) for TGF-β and B cell receptor signal pathways. A total of seventy-four miRNAs were up-regulated and six miRNAs were down regulated in LT with DSA(+) BOS(+) when compared to stable (relative fold >2, p < 0.05). There was also significant enrichment of cell cycle and gap junction pathways. An inverse correlation between expression of two key miRNAs and their target genes were observed: miR-369-5p and miR-548d were down regulated in DSA(+) LT while their gene targets in TGF-β signal pathways were up-regulated. In addition, miR-628-5p and miR-134 were down regulated and their target genes (B cell development) were up-regulated. Therefore, we conclude that alloimmunity induced changes in miRNAs affecting the TGF-β and B cell receptor signal pathways play important roles in BOS development.

Recipient natural killer cell allorecognition of passenger donor lymphocytes and its effect on adaptive alloimmunity after transplantation

BackgroundMemory T cells are known to reside in peripheral non-lymphoid tissue, but how their presence within solid organ allografts affects transplant outcomes is not known. We have previously described how graft-versus-host (GVH) allorecognition by passenger CD4 T cells within MHC class II-mismatched bm12 heart grafts provokes antinuclear humoral autoimmunity in C57BL/6 recipient mice. Here we aimed to examine how such GVH recognition affects the alloresponse to allografts with greater mismatching. MethodsA MHC class I and II mismatched murine model of cardiac transplantation was developed (bm12.Kd.IE to C57BL/6). After transplantation, cellular and humoral responses against mismatched antigens were measured with ELISPOT and ELISA, and the effect of GVH recognition assessed by depletion of donor CD4 T cells before graft procurement. Antinuclear autoantibody development was assessedwith HeP-2 indirect immunofluorescence. The role of recipient natural killer (NK) cells was examined by depletion with anti-NK1.1 antibody. FindingsBm12.Kd.IE heart grafts provoked strong germinal centre alloantibody and autoantibody responses in C57BL/6 recipients and developed allograft vasculopathy. By contrast, heart grafts from CD4 T-cell-depleted donors developed only minimal vasculopathy, and the alloantibody responses were weaker, without observable autoantibody. Bm12.Kd.IE CD4 T cells survived long term when transferred to RAG hosts suggesting that avoidance of killing by host NK cells might be essential for autoantibody development. In support, in a model of alloantibody-mediated vasculopathy, depletion of NK cells from a C57BL/6 recipient of a BALB/c heart graft resulted in the development of autoantibody, amplification of the alloantibody response, and rapid allograft rejection. This amplification was abrogated by depletion of donor CD4 T cells. InterpretationAlthough host adaptive immunity is expected to bring about destruction of passenger lymphocytes within heart allografts, this process occurs too slowly to prevent GVH-mediated augmentation of the alloresponse to the graft. Rather, rapid killing of donor lymphocytes by host alloreactive NK cells is essential. Passenger CD4 lymphocytes might therefore contribute to chronic rejection in recipients receiving an allograft that does not prompt innate NK cell recognition. FundingWellcome Trust Clinical Research Training Fellowship.

English

Kidney transplantation to treat end-stage renal disease has evolved rapidly from the first successful transplantations to the current widespread use of grafts from both cadaveric and living donors. But acute rejection is still a strong risk factor for chronic rejection in recipients of renal grafts. To investigate possible mechanisms, we describe a comparison between different proteins expression profile of acute rejection and the controls. Through two-dimensional difference gel electrophoresis, mass spectral techniques microarray analysis and quantitative real-time RT-PCR confirmation, marked change in expression level of 37 protein spots was observed in allograft rejection group. Among them, expression levels of 24 protein spots were up-regulated, while expression levels of 13 protein spots were down-regulated. Among 37 protein spots, 29 obtained satisfactory peptide mass fingerprinting. We identified 6 proteins in acute rejection after renal transplantation. Then, we investigated PDIA3 levels in serum and transplanted kidney, PDIA3 mRNA and protein expression level. Our data thus indicate that PDIA3 might be potentially involved into the occurrence and development of acute rejection response in renal transplantation. Key words: PDIA3, mass spectrum, acute rejection, renal transplantation.

Expression of CD80 on Cultured Neonatal Mice Cardiomyocytes and Attenuation of Cytotoxic T Lymphocyte–Mediated Lysis

Transplantation of cultured heterogeneous proliferating cardiomyocytes is a promising therapeutic approach for the treatment of the damage cardiac area resulting from myocardial infarction. However, the chances of recipient rejection are high. How to reduce the immunogenicity of heterogeneous cardiomyocytes and attenuate immune rejection is one of the key stumbling blocks in the application of these cells. In this study, we determined that cultured neonatal cardiomyocytes from mice can express CD80 after culture. CD80 is one of the key costimulatory molecules. Most scholars believe that the main function of CD80 is to activate and boost immune rejection. However, recent studies have shown that CD80 may primarily bind with CTLA-4 and inhibit the immune response. To further study how CD80 worked on these cells, a cytotoxic T-lymphocyte (CTL) assay was performed. The results showed that activated allogenic CTLs lysed cultured cardiomyocytes lacking CD80 expression, but they did not efficiently lyse cardiomyocytes expressing CD80. If we blocked the CD80 with anti-CD80 monoclonal antibody (mAb), the percentages of cardiomyocytes lysis were significantly increased. CD80 can bind CD28, CTLA-4, PD-L1, and even B7-H1, but the main ligands are CD28 and CTLA-4. Thus, we blocked the two ligands separately. When anti-CTLA-4 mAb was applied, the percentages of cardiomyocytes lysis were significantly increased, but when anti-CD28 mAb was applied, the percentages of cell lysis were the same as the intact control. The results indicated that CD80 and CTLA-4 played an important role on the attenuation of CTL-mediated lysis. To our knowledge, this study, for the first time, proves that cardiomyocytes can express CD80 and this expression pattern can resist CTL-mediated lysis through CTLA-4 pathway. The results could have implications in efforts to improve therapeutic strategies for cardiomyocyte transplantation.