IgG anti-cardiomyocyte antibodies in giant cell myocarditis

Giant cell myocarditis, a rare, fatal, and poorly understood cause of myocarditis, requires pathological examination for diagnosis. It is considered to be an autoimmune disease and is frequently associated with other conditions, in particular thymoma and myasthenia gravis. The typical patient with giant cell myocarditis is young and has severe, progressive congestive cardiac failure that is unresponsive to standard medical therapy and ultimately requires cardiac transplantation. Hence giant cell myocarditis is the most dangerous form of myocarditis. Here we report an unusual presentation of giant cell myocarditis, which mimicked acute myocardial infarction in an elderly woman with myasthenia gravis and a previous diagnosis of thymoma. This patient had evidence of anti-myocyte antibodies, consistent with an autoimmune mechanism.     

Preformed cytotoxic antibodies in potential allograft recipients: recent data

Presensitization to donor human leukocyte antigen (HLA) remains a major barrier to cell and organ transplantation, thereby contributing to patient mortality. The risks associated with transplantation in the presence of preformed antidonor HLA antibodies range from hyperacute rejection and increased frequency and severity of rejection to no appreciable effect on transplant outcome. Recent evidence has emphasized the importance of immunologic history, anti-HLA antibody class and titer, and differential organ susceptibility to antibody-mediated damage to explain differences in risk for antibody-mediated rejection. Furthermore, in studies of endothelial cells, ligation of class I molecules by subsaturating concentrations of antibodies stimulated expression of cell survival proteins, raising the possibility that, under certain conditions, antibodies promote graft accommodation providing a mechanism for the endothelium to resist immune and inflammatory damage. The discovery of capillary-bound C4d as a robust diagnostic marker for antibody-mediated rejection, coupled with the development of solid-phase assays for the identification of HLA-specific antibodies, has enhanced our ability to detect antibody-mediated rejection and interpret cross-match results. With new diagnostic tools and immunosuppression regimens such as plasmapheresis and intravenous immunoglobulin therapy targeting the humoral immune response, it is time for a concerted effort to reassess the role of alloantibodies in acute and chronic rejection.     

Alloantibodies and the outcome of cadaver kidney allografts

The role of humoral immunity in causing antibody-mediated rejection (AMR) of organ allografts has been extensively documented. For this reason, negative complement-dependent cytotoxicity (CDC) cross-matches between recipient sera and donor T and B lymphocytes have become a mandatory requirement for cadaveric kidney transplantation. However, the significance of donor-specific antibodies (DSAs) detectable only by flow cytometry (FC) or solid phase assays (SPA) but not CDC is still controversial. We have performed a retrospective analysis of FC cross-matching results in 80 consecutive cadaver kidney allograft recipients. Antibodies against HLA class I and class II antigens were measured by CDC and SPA in sequential samples of sera obtained prior to transplantation. The preoperative cross-match was performed by CDC using magnetically sorted T and B cells from donor spleen. Sera obtained from each patient before and at the time of transplantation were included in the final cross-match. The sample of serum obtained at the time of transplantation was cross-matched retrospectively by FC and analyzed for anti-HLA antibody specificity on high resolution SPA. The actuarial kidney allograft survival at one year was 98%. Two of these eighty patients lost the graft, one due to AMR, the other for reasons unrelated to DSAs. Donor-specific antibodies were detected by FC in 17 of 80 patients, yet only 6 of 17 had an early episode of AMR. This episode was successfully reversed by desensitization therapy using intravenous immunoglobin (IVIG) and plasmapheresis. Flow cytomery cross-matching showed 95% specificity but only 35% sensitivity for prediction of AMR (p = 0.002). There was a significant correlation between high panel reactive antibodies (PRA) and positive FC cross-matching (p = 0 .0001), as well as high PRA and AMR (p = 0.0004 by CDC and 0.0011 by Luminex). Reversible AMR occurred 12-30 days post-transplantation in 8 patients. Of these 8 patients, 3 had no detectable DSAs in spite of C4d positivity, 4 had C4d deposition in conjunction with anti-HLA antibodies, and 1 patient had DSAs (anti-MICA) yet no C4d deposition. We conclude that early initiation of desensitization protocols can prevent transplant failure and that retrospective FC cross-matches may facilitate the diagnosis of AMR. Extensive analysis of patients' sera using a comprehensive set of tests may contribute to early treatment and better understanding of the mechanism underlying humoral rejection.     

Therapeutic implications of immune mechanisms in myocarditis

Conclusions Although it is attractive to postulate that immunosuppressive therapy will be effective in biopsy-proven myocarditis, available published reports do not validate this conclusion. If the myocarditis Treatment Trial demonstrates that immunosuppression is not efficacious, then cardiac allograft rejection will remain the only major indication for endomyocardial biopsy, in which case this technique should be restricted to large referral centers. If immunosuppression is effective, other trials will be necessary to determine the optimal combination of immunosuppressive agents and duration of therapy. This study will also clarify the natural history of myocarditis and allow more accurate prognostication in this group of patients which will help in selection of those who may require cardiac transplantation.     

Comparative analysis of how immune sensitization is defined prior to lung transplantation

BackgroundImmune sensitization prior to lung transplantation may be associated with worse survival. Using solid phase assays to define sensitization, we assessed the relationship between PRA status, donor specific anti-HLA antibodies (DSA) pre-transplant, cytotoxic cross match results and the clinical outcomes following lung transplantation.MethodsLuminex assays determined the presence of antibodies to class I and class II MHC molecules prior to lung transplantation. At the time of transplant, the PRA status, the presence of DSA and prospective cytotoxic cross match result were analysed in 195 patients undergoing lung transplantation between June 2008 and June 2012. Clinical outcomes analysed included acute cellular and antibody-mediated rejection, chronic lung allograft dysfunction (CLAD) and mortality.ResultsAt the time of transplant, 45% of patients had a positive PRA and 29% had DSA. On univariate analysis, the presence of pre-transplant class I or II anti-HLA donor-specific antibodies was not associated with the development of chronic lung allograft dysfunction (CLAD) despite significant associations with PRA status and B-cell crossmatch.ConclusionDefining sensitization using solid phase assays provide additional details regarding donor-specific sensitization but did not provide additional prognostic information to that provided by historically available cell-based cross-match assays.     

Survival outcomes of patients with giant cell myocarditis bridged by ventricular assist devices

Giant cell myocarditis is a highly lethal disorder characterized by rapidly progressive congestive heart failure. The aim of this study was to describe the clinical course of patients with giant cell myocarditis who received a ventricular assist device. Patients with giant cell myocarditis were identified from the Multicenter Giant cell Myocarditis Registry. Bridging to cardiac transplantation in the giant cell myocarditis patients who received a ventricular assist device was compared with bridging in the general population of heart failure patients, as reported in the literature. Median posttransplantation survival for patients with giant cell myocarditis who received and did not receive ventricular assist devices was calculated by the Kaplan-Meier method and compared with use of the log-rank test. Nine patients with giant cell myocarditis who received ventricular assist devices were identified. Seven patients survived to transplantation, four were alive 30 days posttransplantation, and two survived to 1 year. The rate of successful bridging to transplantation in seven of nine patients (78%) is similar to that reported for other ventricular assist device recipients. Posttransplantation survival of 57% (4 of 7) at 30 days and 29% (2 of 7) at 1 year was significantly lower compared with 93% 1-year survival of the 30 patients with giant cell myocarditis who did not receive ventricular assist devices before transplantation (p<0.001). Ventricular assist devices can be an effective bridge to transplantation for patients with heart failure caused by giant cell myocarditis. Although their posttransplantation survival was poor in our series, a few patients had long-term survival.     

Influence of HLA disparity,immunosuppressive regimen used,and type of kidney allograft on production of anti-HLA class-I antibodies after transplant and occurrence of rejection

We studied the effects of HLA disparity, immunosuppressive regimen used, and the type of kidney allograft on production of anti-HLA antibodies after transplant and the occurrence of rejection episodes.

Five living-unrelated donors and 4 living-related donors kidney recipients received quadruple therapy (including sirolimus and mycophenolate mofetil). Fifteen living-unrelated donors and 19 living-related donors received triple therapy (excluding sirolimus). A single bolus of 4 to 6 mg/kg rabbit anti-human T-lymphocyte immune serum was included with both regimens. Recipients were studied over a 3-year period. Human leukocyte antigen profiles were determined by DNA (SSP) typing, and anti-HLA class-I antibodies were determined by the complement-dependent microcytotoxicity assay and an enzyme-linked immunosorbent assay.

The degree of HLA disparity did not appear to affect anti-HLA antibody production or the occurrences of rejection episodes. None of the patients who received quadruple therapy developed anti-HLA class-I antibodies. Two living-unrelated donors and 2 living-related donors recipients who received triple therapy developed anti-HLA class-I antibodies. One of the 2 living-unrelated donors antibody-positive patients rejected the kidney and returned to dialysis, and the other patient has normal graft function 3 years after the transplant. The 2 living-related donors patients with normal graft function were antibody-positive 1 year after the transplant but were antibody-negative at 2 and 3 years after transplant.

Sirolimus appeared to inhibit production of antibodies after transplant. Moreover, use of present day immunosuppressive agents diminishes the role of HLA matching in relation to the occurrence of rejection episodes.     

Influence of HLA disparity, immunosuppressive regimen used, and type of kidney allograft on production of anti-HLA class-I antibodies after transplant and occurrence of rejection

We studied the effects of HLA disparity, immunosuppressive regimen used, and the type of kidney allograft on production of anti-HLA antibodies after transplant and the occurrence of rejection episodes. Five living-unrelated donors and 4 living-related donors kidney recipients received quadruple therapy (including sirolimus and mycophenolate mofetil). Fifteen living-unrelated donors and 19 living-related donors received triple therapy (excluding sirolimus). A single bolus of 4 to 6 mg/kg rabbit anti-human T-lymphocyte immune serum was included with both regimens. Recipients were studied over a 3-year period. Human leukocyte antigen profiles were determined by DNA (SSP) typing, and anti-HLA class-I antibodies were determined by the complement-dependent microcytotoxicity assay and an enzyme-linked immunosorbent assay. The degree of HLA disparity did not appear to affect anti-HLA antibody production or the occurrences of rejection episodes. None of the patients who received quadruple therapy developed anti-HLA class-I antibodies. Two living-unrelated donors and 2 living-related donors recipients who received triple therapy developed anti-HLA class-I antibodies. One of the 2 living-unrelated donors antibody-positive patients rejected the kidney and returned to dialysis, and the other patient has normal graft function 3 years after the transplant. The 2 living-related donors patients with normal graft function were antibody-positive 1 year after the transplant but were antibody-negative at 2 and 3 years after transplant. Sirolimus appeared to inhibit production of antibodies after transplant. Moreover, use of present day immunosuppressive agents diminishes the role of HLA matching in relation to the occurrence of rejection episodes.     

抗人类白细胞抗原抗体与抗内皮细胞抗体在肾移植慢性排斥反应中作用的相关性

目的 选择发生慢性排斥反应的肾移植患者,根据人类白细胞抗原(human leukocyte anti-gen,HLA)抗体阳性或抗内皮细胞抗体阳性以及两抗体同时阳性进行分组,并同时检测各组患者的血清中肌酐含量作为判断肾功能的指标.探讨在肾移植慢性排斥反应中抗内皮细胞抗体与抗HLA抗体作用的相关性.方法 抗内皮细胞抗体的检测方法用免疫荧光法,抗HLA抗体应用酶联免疫吸附试验(enzyme linked immunosorbent assay,ELISA),肌酐检测应用的是生化分析仪.结果 移植后处于慢性排斥期抗HLA抗体阳性的患者血清肌酐含量均值为(116.3±5.6)μmol/L,抗内皮细胞抗体阳性的患者血清肌酐含量均值为(114.6±4.7)μmol/L;抗HLA抗体与抗内皮细胞抗体同时阳性的血清标本肌酐含量的中位数是131.2μmol/L,四分位间距为13.6μmol/L;两组间肌酐含量差异有统计学意义(P=0.000).结论 抗内皮细胞抗体和抗HLA抗体均可影响肾移植慢性排斥反应期的肾功能;抗内皮细胞抗体与抗HLA抗体在肾移植慢性排斥期间同时产生,肾功能损害加重.     

Evaluation of three different laboratory methods to detect preformed human leukocyte antigen antibodies in a South African kidney transplant population

BackgroundAnti-human leukocyte antigen antibodies (anti-HLA) play a crucial role in graft. Detection of anti-HLA, both pre- and post-transplant is a crucial investigation in clinical organ transplantation.ObjectivesThree methodologies for the detection of lymphocytotoxic antibodies were compared to establish which of these is best suited to optimise pre-transplant donor-recipient matching.MethodsSerum samples from 15 renal transplant patients were tested for the presence of anti-HLA by i) cytotoxic-dependent cross-match (CDCXM), ii) flow cytometric cross-match (FCXM) and iii) Luminex-based donor specific antibody cross-match (DSAXM) method, Confirmatory tests for the presence of preformed HLA antibodies were tested using Luminex methodology.ResultsTwo (13%) of the 15 patients had positive HLA Class I antibodies (Ab) using all 3 methods. An additional 2 HLA Class I Ab were identified with FCXM/CDCXM. DSAXM identified 1 HLA Class I positive, not indicated by CDCXM/FCXM.High HLA Class II positivity (40%), identified by CDCXM, while DSAXM and FCXM identified two and one patients, respectively. CDCXM produced 4 false-positive results confirmed by lymphocyte single antigen (LSA) assay.ConclusionsThe DSAXM method appears to add value in pre-transplantation screening to identify pre-sensitised patients that may not reject the donor graft due to the absence of donor-specific antibodies.     

Giant cell myocarditis in association with drug-induced skin eruption

A case of giant cell myocarditis in a 19-year-old woman is presented. She had high fever, vomiting, epigastralgia, cardiomegaly, and disseminated papular erythema probably due to anti-epileptic agents. At autopsy, giant cell myocarditis and the myositis of the systemic skeletal muscles were found. To our knowledge, no case of giant cell myocarditis in association with drug-induced skin eruption was reported. This is a rare case of giant cell myocarditis.     

GIANT CELL MYOCARDITIS IN ASSOCIATION WITH DRUG-INDUCED SKIN ERUPTION

A case of giant cell myocarditis In a 19-year-old woman is presented. She had high fever, vomiting, epigastralgia, cardiomegaly, and disseminated papular erythema probably due to anti-epileptic agents. At autopsy, giant cell myocarditis and the myositis of the systemic skeletal muscles were found. To our knowledge, no case of giant cell myocarditis in association with drug-induced skin eruption was reported. This is a rare case of giant cell myocarditis.     

Acute idiopathic interstitial myocarditis: case report with special reference to morphological characteristics of giant cells.

Necropsy findings of an acute fatal case of idiopathic interstitial myocarditis were reported. The patient was a 33 year old housewife who had acute cardiac failure on the sixteenth day after the onset of the disease. Necropsy showed important pathological changes confined to the heart. Both ventricles were affected by confluent granulomas with an ill defined patchy appearance. Histologically these lesions consisted of round cells, histiocytes, eosinophils and myogenic giant cells. The findings were compatible with those of interstitial myocarditis associated with a proliferation of giant cells. Both atriums were also affected to a minor extent, detectable only by histological examination. Electron microscopy and cytochemistry showed that most giant cells noted in the lesion showed myofibrils and primary lysosomes in the cytoplasm. Giant cells were positive for myoglobin. Though the macrophage origin of the giant cell in this disorder has been emphasised in a recent report, these cytological results suggest that giant cells observed in the cardiac granulomatous lesions of this case were mainly myogenic in origin.     

Absence of Trypanosoma cruzi myocardial infection reactivation in Chagas'' heart transplant

The risk of Trypanosoma cruzi myocardial infection reactivation after immunosuppressive therapy has led to precluding heart transplantation as a therapeutic procedure for patients with end-stage Chagas' heart disease. We report a case of an orthotopic heart transplantation in a 43-year-old critically ill chagasic patient with an uneventful postoperative period. He was treated with azathioprine and cyclosporine to control graft rejection and showed no reactivation of the chagasic infection. One year following surgery, the patient is doing well. Nonsteroidal therapy appears not to reactivate T. cruzi infection in transplant chagasic patients.     

临床活体肝部分移植受体的免疫抑制治疗

目的 报道１例临床活体肝部分移植受体的免疫抑制治疗情况。方法 １９９７年６月３０日,我科成功地施行了１例活体肝部分移植术,术后采用皮质激素、硫唑嘌呤、环孢素Ａ三联免疫抑制治疗,并监测环孢素Ａ的血药浓度。术后第１０天,发生急性移植排斥反应,经皮质激素冲击治疗及增加环孢素Ａ的用量后,排斥反应被逆转。在恢复期,采用小剂量的环孢素Ａ和骁悉维持治疗。结果 目前患者一般情况良好,已健康生存２年９个月。结论 活     

Isoniazid in patient plasma may cause a false-positive result on the complement-dependent cytotoxicity test

Correct definition of clinically relevant anti-HLA antibodies is important for transplant organ allocation and outcome. We describe a candidate for kidney transplantation who was treated with isoniazid because of active tuberculosis. The patient's serum gave a positive antibody result on screening with the complement-dependent cytotoxicity (CDC) test but a negative result on screening with a bead-based assay (Luminex). The clinical history indicated no immunologic stimuli. Subsequent testing on fresh serum samples confirmed the discrepancy between CDC and Luminex results. An autologous cross-match test gave negative results, and the antibodies were sensitive to dithiothreitol treatment. We postulated that nonspecific binding of drug–antibody complexes to panel lymphocytes in the CDC test may have caused the observed lympholysis. This case, although isolated, emphasizes the importance of the combined use of CDC and solid phase assays. The CDC results alone would have led to the erroneous conclusion that the patient was highly sensitized.     

Association of kidney transplant failure and antibodies against MICA

Despite the progress in renal transplantation, acute rejection and graft failure still occur and chronic rejection continues to be the main problem in long-term allograft survival. Although kidney transplant rejection has been linked to anti-HLA antibodies, not all patients with failed kidney transplants have anti-HLA antibodies, indicating that other loci may be involved. Sera of 63 patients who experienced kidney rejection were compared against sera of 82 patients with functioning transplants. Sera were examined for IgG and IgM anti-HLA Class I and II antibodies. They were also tested by cytotoxicity against panels of 26 endothelial cell lines, 8 MHC class I chain-related gene A (MICA) recombinant cell lines, and 28 B lymphoblast cell lines. Among patients whose transplants failed, 65% had anti-HLA antibodies compared with 45% of those with functioning kidneys (p < 0.05). Similarly, among those whose transplants failed, 41% had anti-endothelial cell antibodies in contrast to 22% in functioning patients (p < 0.05). Among patients whose grafts failed, 52% had anti-MICA antibodies versus 21% of those with functioning grafts (p < 0.001). Eleven patients with failed grafts and 32 with functioning grafts were negative for all of the above. However, 6 of the former and 7 of the latter showed positive cytotoxicity against B lymphoblasts (p < 0.05). Taking all antibodies together, 92% of patients with graft failure had antibodies as opposed to 70% of patients with functioning grafts (p < 0.001). We postulate that antibodies against HLA, MICA, endothelial cells, and B lymphoblasts could be independently involved in the slow process of chronic graft failure.     

Giant cell myocarditis associated with lymphoma: an immunocytochemical study.

A case of giant cell myocarditis in a patient with non-Hodgkin's lymphoma is reported. To our knowledge, this is a previously unrecorded association and supports the hypothesis that the aetiology of giant cell myocarditis is related to a changed immune state. Immunohistochemical investigation of this case with a panel of monoclonal antibodies against a range of leucocyte and muscle antigens supports the view that the giant cells have a histiocytic rather than a myogenic origin.     

CHRONIC REJECTION: PROSPECTS FOR THERAPEUTIC INTERVENTION IN FIBROPROLIFERATIVE VASCULAR DISEASE

The graft survival rates of sensitized kidney recipients have been shown to be lower than those of nonsensitized patients. Therefore, panel reactive antibody (PRA) and cross-match determination is accepted as mandatory screening for renal transplantation candidates. Our recent previous study showed that simvastatin has a significant immunosuppressive effect in PRA-positive and/or crossmatch-positive patients. We present the long-term pre and post-transplantation outcomes of simvastatin treatment in highly sensitized dialysis patients. Thirty patients were followed for a mean period of 22 months. The PRA and flow cytometric measurements were performed at monthly intervals. Ten patients underwent successful kidney transplantation (eight living-related and two cadaveric). None of the patients developed hyperacute or acute rejection, and there was no graft loss during the 16.1±8.2 months of post-transplantation follow up. Of the 18 patients who stayed on dialysis throughout the study with PRA-positivity, six were lost to follow up and three spontaneously stopped taking the simvastatin. In the latter three cases, the PRA levels rose significantly after the drug was discontinued. Eight of the remaining nine PRA-positive patients showed significant drops in mean PRA level over the study period, and entered the range considered acceptable for transplantation. Only one patient showed persistently high PRA levels throughout the study. In one patient, the drug had to be discontinued because of acute toxic hepatitis. In conclusion, the results indicate that long-term continuous simvastatin therapy is effective in immunized and highly sensitized dialysis patients. Meanwhile, it has a beneficial effect on 1-year graft survival rates in sensitized renal transplantation patients.