Everolimus is associated with a reduced incidence of cytomegalovirus infection following de novo cardiac transplantation.

BACKGROUND: Cytomegalovirus (CMV) causes several complications following cardiac transplantation including cardiac allograft vasculopathy. Previous studies suggested that immunosuppressive treatment based on everolimus might reduce CMV infection. Aiming to better characterize the action of everolimus on CMV and its interplay with patient/recipient serology and anti-CMV prophylaxis, we analyzed data from 3 large randomized studies comparing various everolimus regimens with azathioprine (AZA)- and mycophenolate mofetil (MMF)-based regimens. METHODS: CMV data were analyzed from 1009 patients in 3 trials of de novo cardiac transplant recipients who were randomized to everolimus 1.5 mg/day, everolimus 3 mg/day, or AZA 1-3 mg/kg/day, plus standard-dose (SD) cyclosporine (CsA; study B253, n = 634); everolimus 1.5 mg/day plus SD- or reduced-dose (RD)-CsA (study A2403, n = 199); and everolimus 1.5 mg/day plus RD-CsA or MMF plus SD-CsA (study A2411, n = 176). RESULTS: In study B253, patients allocated to everolimus experienced almost a 70% reduction in odds of experiencing CMV infection compared with AZA (P < 0.001). In study A2403, CMV infection was low in both everolimus arms, irrespective of CsA dosing, and in study A2411, patients allocated to everolimus experienced an 80% reduction in odds of experiencing CMV infection, compared with MMF (P < 0.001). CMV syndrome/disease was rare and less frequent in everolimus-treated patients. Subgroup analyses showed that the benefit everolimus provides, in terms of CMV events, is retained in CMV-naïve recipients and is independent of anti-CMV prophylaxis or preemptive approaches. CONCLUSIONS: Everolimus is associated with a lower incidence of CMV infection compared with AZA and MMF, which combined with its immunosuppressive efficacy and antiproliferative effects may positively impact long-term outcomes.

Human platelet antigen genotypes in Turkish and Caucasian blood donors in Germany.

Exposition to allogenic human platelet antigens (HPAs) can lead to antibody formation causing neonatal alloimmune thrombocytopenia (NAIT), post-transfusion purpura or platelet (PLT) transfusion refractoriness. The frequencies of HPA differ between ethnical groups which could be associated with different potential alloimmunization risk. The Turkish population is the largest ethnic minority group living in Germany. However, no data are available about the HPA frequency among Turkish population. We compared the frequency of HPA between Caucasian and Turkish blood donors. DNA from blood samples of 119 Caucasian and 117 Turkish blood donors was isolated. The genotype of HPA-1, -2, -3 -4, -5 and -15 was determined using a commercialized polymerase chain reaction kit with sequence-specific primers. In Turkish blood donors, the gene frequencies of HPA-1a/1b, -2a/2b, -3a/3b, -4a/4b, -5a/5b and -15a/15b were 0.863/0.137, 0.868/0.133, 0.607/0.393, 0.996/0.004, 0.893/0.107 and 0.474/0.256, respectively. In Caucasians, we observed 0.798/0.202, 0.908/0.092, 0.567/0.432, 1.000/0.000, 0.916/0.084 and 0.517/0.483 for HPA-1a/1b, -2a/2b, -3a/3b, -4a/4b, -5a/5b and -15a/15b, respectively. No statistically significant difference between genotypes in these populations could be observed. Due to the similar distribution of HPA genotypes in both ethnical groups, no increased risk of NAIT for children of mixed couples or of post-transfusion purpura or PLT transfusion refractoriness secondary to antibodies to HPAs for recipients of PLT concentrates from blood donors of the other ethnicity is given.

Human neutrophil alloantigen genotype frequencies among blood donors with Turkish and German descent.

Antibodies against the human neutrophil antigens (HNA) are able to stimulate transfusion reactions, autoimmune and neonatal neutropenia. The aim of this study was to determine the HNA allele frequencies in the largest ethnic minority group in Germany in comparison with the German population for predicting the risk of alloimmunization and associated transfusion reactions, as well as the risk of developing neonatal neutropenia for the newborn of racial mixed couples. However, there exists no data about HNA genotype distribution in Turkish population. DNA was isolated from blood samples of 119 German and 118 Turkish blood donors and typed them for HNA-1, -3, -4, and -5 by using a commercial polymerase chain reaction kit with sequence-specific primers (SSP-PCR) and compared the HNA genotype distribution of both groups. In German blood donors, the gene frequencies for HNA-1a and HNA-1b were 0.391 and 0.601, for HNA-3a and -3b, 0.744 and 0.256, for HNA-4a and -4b, 0.908 and 0.092, and for HNA-5a and -5bw, 0.731 and 0.269. In Turkish blood donors, we observed 0.420/0.564, 0.737/0.263, 0.881/0.119, and 0.754/0.246 for HNA-1a/1b, -3a/3b, -4a/4b, and -5a/5bw. No statistic significant difference between genotypes in these populations was observed. This study is the first to report HNA gene frequencies in a Turkish population. It showed that there is no difference of HNA genotype in blood donors with Turkish descent in comparison with German blood donors. The alternating transfusion of blood and blood components is no increased risk for developing alloantibodies against HNA antigens. In pregnancy of mixed couples no special screening programs for HNA are necessary.

PARP inhibition in atherosclerosis and its effects on dendritic cells, T cells and auto-antibody levels.

OBJECTIVE: Atherosclerosis is a chronic inflammatory process. Poly(ADP-ribose) polymerase-1 (PARP), a nuclear enzyme linked to DNA repair, has been shown to be involved in atherogenesis; however, the effects on dendritic cells, T cells and serum auto-antibody levels are not fully understood. METHODS: Male Apoe-/- mice on a western diet were treated with the PARP inhibitor INO-1001 (n = 15), while the control group (n = 15) received 5% glucose solution for 10 weeks. RESULTS: Inhibition of PARP markedly reduced atherosclerotic lesion development (p = 0.001). Immunohistochemistry and mRNA analysis revealed a reduced inflammatory compound inside the lesion. Focusing on dendritic cells, INO-1001 reduced number of cells (p = 0.04), grade of activation, represented by Il12 (p = 0.04) and Cd83 (p = 0.03), and grade of attraction, represented by Mip3α (p = 0.02) in the plaque. Furthermore, INO-1001 decreased number of T lymphocyte (p = 0.003) in the lesion and grade of activation after stimulation with oxLDL in vitro. Moreover, serum IgM antibody levels to oxLDL were significantly lower in INO-1001 treated mice (p = 0.03). CONCLUSIONS: Functional blockade of PARP by INO-1001 reduces atherosclerotic lesion development. The anti-atherogenic effect is beside already known mechanisms also moderated due to modulation of DC and T cell invasion and activation, DC attraction as well as IgM antibody levels to oxLDL.

Lower incidence of cytomegalovirus infection with everolimus versus mycophenolate mofetil in de novo cardiac transplant recipients: a randomized, multicenter study.

Cytomegalovirus (CMV) is a major cause of infectious complications following cardiac transplantation, severely affecting short- and long-term outcomes. A 12-month, multicenter, randomized, open-label study in de novo cardiac transplant patients was undertaken to compare the efficacy, renal function, and safety of everolimus plus reduced cyclosporine versus mycophenolate mofetil (MMF) plus standard cyclosporine (ClinicalTrials.gov NCT00150046). CMV-specific data was prospectively collected on infections, laboratory evidence, CMV syndrome, and CMV disease. In total, 176 patients were randomized (everolimus 92; MMF 84). Use of CMV prophylaxis was similar between groups (everolimus 20.8%; MMF 24.0%). Patients in the everolimus arm had a significantly lower incidence of any CMV event (8.8% versus 32.5% with MMF, P<0.001), CMV infection as an adverse event (4.4% versus 16.9%, P=0.011), laboratory evidence of CMV (antigenemia 7.7% versus 27.7%, P<0.001; polymerase chain reaction assay 2.2% versus 12.0%, P=0.015), and CMV syndrome (1.1% versus 8.4%, P=0.028). In the donor (D)+/recipient (R)+and D-/R+ subgroups, even after adjusting for use of prophylaxis, the CMV event rate remained significantly lower with everolimus than with MMF (P=0.0015 and P=0.0381, respectively). In conclusion, de novo cardiac transplant recipients experienced lower rates of CMV infection, CMV syndrome, or organ involvement on an everolimus-based immunosuppressant regimen compared with MMF.

Strain-encoded cardiac magnetic resonance for the evaluation of chronic allograft vasculopathy in transplant recipients.

The aim of our study was to investigate the ability of Strain-Encoded magnetic resonance imaging (MRI) to detect cardiac allograft vasculopathy (CAV) in heart transplantation (HTx)-recipients. In consecutive subjects (n = 69), who underwent cardiac catheterization, MRI was performed for quantification of myocardial strain and perfusion reserve. Based on angiographic findings subjects were classified: group A including patients with normal vessels; group B, patients with stenosis <50%; and group C, patients with severe CAV (stenosis >or= 50%). Significant correlations were observed between myocardial perfusion reserve with peak systolic strain (r =-0.53, p < 0.001) and with mean diastolic strain rate (r = 0.82, p < 0.001). Peak systolic strain and strain rate were significantly reduced only in group C, while mean diastolic strain rate and myocardial perfusion reserve were already reduced in group B and A. Myocardial perfusion reserve and mean diastolic strain rate had higher accuracy for the detection of CAV (AUC = 0.95, 95% CI = 0.87-0.99 and AUC = 0.93, 95% CI = 0.84-0.98, respectively) and followed peak systolic strain and strain rate (AUC = 0.80, 95% CI = 0.69-0.89 and AUC = 0.78, 95% CI = 0.67-0.87, respectively). Besides the quantification of myocardial perfusion, the estimation of the diastolic strain rate is a useful parameter for CAV assessment. In combination with the clinical evaluation, these parameters may be effective tools for the routine surveillance of HTx-recipients.

Proinflammatory and prothrombotic effects on human vascular endothelial cells of immune-cell-derived LIGHT.

OBJECTIVE: LIGHT (TNFSF 14) belongs to the tumor necrosis factor superfamily and is expressed by activated T cells as well as various types of antigen presenting cells. LIGHT binds to its cellular receptors TR2 and LTbetaR and has a co-stimulatory role in T cell activation. Here, we compared the relative expression of LIGHT in different immune cells and the biological activity of immune cell-derived LIGHT on endothelial cells. METHODS AND RESULTS: Surface expression of LIGHT and mRNA production by PBMC and isolated T cells (CD4+ or CD8+) significantly increased after stimulation with PMA (Phorbolester-12- Myristat-13-Acetat)+ionomycin. No LIGHT expression on PMA stimulated monocytes or monocytic-like THP-1 cells could be detected; differentiation of monocytes and THP-1 cells into macrophages, however, resulted in up-regulation of LIGHT. Supernatants of stimulated T cells contained higher concentrations of soluble LIGHT than macrophage supernatants normalized to cell numbers; release of soluble LIGHT was found to be dependent on metalloproteinase activity. Size determination of released soluble LIGHT by size exclusion chromatography revealed a molecular mass of approximately 60 kDa, suggesting a trimeric form. Released soluble LIGHT induced expression of proinflammatory antigens ICAM-1, tissue factor and IL-8 in human endothelial cells and caused apoptosis of IFN-g pretreated endothelial cells. Soluble LIGHT was detected at low levels in sera of healthy controls and was significantly enhanced in sera of patients with chronic hepatitis C and rheumatoid arthritis (24.93+/-9.41 vs. 129.53+/-49.14 and 172.13+/-77.64; p<0.0005). CONCLUSION: These findings suggest that among immune cells activated T lymphocytes are the main source of soluble LIGHT with released amounts of soluble LIGHT markedly higher compared to platelets. Immune cell-derived membrane-bound and soluble trimeric LIGHT is biologically active, inducing proinflammatory changes in endothelial cells. Enhanced plasma levels of soluble LIGHT in patients with chronic infections suggest a role of LIGHT in systemic inflammatory activation.

[Risk stratification and treatment of cardiac amyloidoses]. / Risikostratifizierung und Therapie kardialer Amyloidosen.

Cardiac amyloidoses are a heterogeneous group of cardiomyopathies that are resistant to treatment and are associated with a poor outcome. Standard heart failure treatment is usually not well tolerated and the underlying disease remains unaffected. The clinical picture is uncharacteristic. Cardiac amyloidosis is often associated with dysfunction of additional organs. Early cardiac amyloid involvement usually reveals left ventricular hypertrophy, impairment of longitudinal shortening and diastolic ventricular function. Without adequate therapy (bi-)ventricular hypertrophy will progress to severe systolic ventricular function decrease. The combination of low voltage pattern, left ventricular hypertrophy and granular sparkling is characteristic for advanced cardiac amyloid involvement. Cardiac magnetic resonance imaging and scintigraphy yield further information on the pattern and severity of cardiac involvement. In unclear cases (left ventricular) endomyocardial biopsy is necessary. Detection of early cardiac involvement and proper identification of patients at high risk for sudden cardiac death due to rapid progressive amyloidosis is still incompletely defined. Referral to specialized centers is strongly recommended.

[MR imaging in cardiac amyloidosis--morphology, function and late enhancement]. / Magnetresonanztomografie bei kardialer Amyloidose--Morphologie, Funktion und late enhancement.

PURPOSE: Since limited data is available using MR imaging in cardiac amyloidosis, the purpose of our study was to evaluate morphological and functional differences of the heart using cardiac MRI. MATERIALS AND METHODS: 19 consecutive patients (14 males, 5 females, mean age 59 +/- 6 years) with histologically proven cardiac amyloidosis were evaluated with MRI at 1.5 T. Results were compared with data of 10 healthy, age-matched control subjects (5 males, 5 females, mean age 60 +/- 6 years). Functional and morphological data including late enhancement (LE) was acquired. RESULTS: Compared to the control group, patients with cardiac amyloidosis had thickened atrial walls and dilated atriums. Both ventricles and the interventricular septum were thickened. The LV hypertrophy was focal in 11 / 19 (58 %) and global in 4 / 19 (21 %) of patients. A myocardial edema occurred in 2 / 19 patients with cardiac amyloidosis (11 %). An edema of the myocardium was visible in 2 / 19 (11 %) of patients. The LV ejection fraction was statistically significantly decreased. The prevalence of LE was 74 % (14 / 19 of patients). LE was detected predominantly in the LV anterior wall and in the interventricular septum. Within the segments LE was located predominantly in a subendocardial location. Between patients with and without LE no statistically significant differences of functional and morphological results were able to be established. CONCLUSION: There are three major outcomes of our assessment: 1. The LV hypertrophy is focal in the majority of patients with cardiac amyloidosis. 2. No statistically significant differences can be established in regard to the functional and morphological features between patients with and without LE. 3. Myocardial edema is a possible feature in cardiac amyloidosis.

Enteric-coated mycophenolate-sodium in heart transplantation: efficacy, safety, and pharmacokinetic compared with mycophenolate mofetil.

Mycophenolic acid (MPA) is an effective immunosuppressive treatment for renal transplant recipients, but its effective use and best practice are not established in cardiac transplantation. This multicenter, single-blind, randomized, parallel group clinical trial prospectively evaluated the therapeutic equivalence of enteric-coated mycophenolate-sodium (EC-MPS) versus mycophenolate mofetil (MMF) in combination with cyclosporine (CyA) and steroids as determined by the primary objective of treatment efficacy during the first 6 months of treatment in 154 de novo heart transplant recipients. Both groups received equivalent doses of MPA, either 720 mg b.i.d EC-MPS or 1000 mg b.i.d MMF. EC-MPS showed a comparable efficacy and safety profile compared with MMF with significantly less dose reduction. Treatment failure occurred in 57.7% and 60.5% with EC-MPS and MMF, respectively, EC-MPS was therapeutically equivalent to MMF in cardiac transplantation.

Impact of apoptosis in acute rejection episodes after heart transplantation: immunohistochemical examination of right ventricular myocardial biopsies.

OBJECTIVE: Acute rejection may lead to cell death following heart transplantation. Programmed cell death (apoptosis) has been described as a cofactor for cell loss in cardiac tissue. The aim of our study was to quantify the amount and extent of apoptotic cells during acute rejection episodes after orthotopic heart transplantation. PATIENTS AND METHODS: Right ventricular biopsies from 27 heart transplant recipients were classified histologically according to rejection grade. Formalin-fixed sections were processed for immunohistochemistry. TUNEL-positive cells were counted and the expression of apoptosis-modulating factors Bax, Bcl-x(L), Bcl-2, and Ki-67 (proliferation marker) was scored. P

Interstitial leukocytes in right ventricular endomyocardial biopsies after heart transplantation in patients with complicated versus uneventful postoperative course.

BACKGROUND: Infections and rejections play key roles in morbidity and mortality in the early postoperative period after orthotopic heart transplantation (HTX). The aim of this study was to evaluate whether qualitative and quantitative analyses of various interstitial leukocytes in endomyocardial biopsies during the first 2 weeks after HTX provided early information on these complications. PATIENTS AND METHODS: During and after HTX, endomyocardial biopsies were obtained in 51 patients. By immunohistochemistry we determined the CD3-, CD4-, CD8-, CD15-, CD20-, CD57-, and CD68-positive cell numbers projected to planimetrically measured areas. To compare morbidity in the postoperative course, the patients were subdivided into complicated versus uncomplicated after 3 months. RESULTS: In the uncomplicated group, the cell counts of CD3-, CD8-, CD57-, and CD68-positive cells were significantly lower than in the complicated group. CD3-, CD4-, and CD8-positive cell numbers showed a significant decrease in the first week among the uncomplicated group. In the complicated group, the cell counts increased significantly in the second week. The numbers of CD57-positive cells were significantly lower during the first and second weeks among the uncomplicated group. CONCLUSIONS: Increased T lymphocytes, natural killer cells, and macrophages observed in the second week after HTX indicated increased morbidity. A reduction in CD3-positive cells in the first week indicated a low morbidity risk; an increase indicated a higher risk.

Differentiated expression patterns of growth factors in routine formalin-fixed endomyocardial biopsies in the early postoperative phase after heart transplantation.

BACKGROUND: Platelet-derived growth factor (PDGF) and fibroblast growth factor (FGF) seem to play a key role in immunological reactions shortly after heart transplantation (HTx). The aim of this study was to analyze the time course of the expression of PDGF A and B, PDGF-receptor alpha (PDGF-Ralpha) and beta, aFGF, and bFGF on formalin-fixed routine endomyocardial biopsies. PATIENTS AND METHODS: Right ventricular endomyocardial biopsies were obtained from 36 heart transplant recipients up to 2 weeks after HTx. According to the clinical course in the first postoperative year, 3 groups were formed: (1) clinically uneventful course (n = 12); (2) cardiac/systemic infections (n = 12); (3) acute rejection (n = 12). The growth factor expression was examined immunohistochemically. RESULTS: In the early phase after HTx, PDGF A, PDGF B, PDGF-Ralpha, and PDGF-Rbeta were predominantly expressed in endothelial cells. The main expression of PDGF-Ralpha and bFGF was found in cardiomyocytes, endothelial cells, and smooth muscle cells. During the first 2 postoperative weeks, PDGF A, PDGF B, and PDGF-Rbeta showed a similar time course of expression: A significantly elevated expression in the first week was followed by a decrease in the second week. In the rejection group, PDGF A was significantly elevated after the first week. CONCLUSIONS: The increased expression of PDGF in the first postoperative week can be interpreted as an unspecific reaction to peritransplant injury. The prolonged expression of PDGF A, PDGF B, and PDGF-Rbeta showed that there were ongoing immunological reactions in the transplant during week 2. The persistence of elevated PDGF A expression might be of prognostic value in terms of a risk factor for either infection or rejection.

Elevated serum concentrations of cardiac troponin T in acute allograft rejection after human heart transplantation.

OBJECTIVES: This study evaluates the concept and diagnostic efficacy of using serum troponin T for the detection of cardiac graft rejection. BACKGROUND: Cardiac troponin T is a cardiospecific myofibrillar protein, which is only detectable in the circulation after cardiac myocyte damage. It might be expected to be released during acute heart allograft rejection, allowing noninvasive rejection diagnosis. METHODS: In 35 control subjects and in 422 samples from 95 clinically unremarkable heart allograft recipients more than 3 months postoperatively, troponin T serum concentrations were compared to the histological grade of acute graft rejection in concurrent endomyocardial biopsies. RESULTS: Mean troponin T serum concentrations were identical in control subjects (23.2 +/- 1.4 ng/liter) and in heart transplant recipients without graft rejection (International Society for Heart and Lung Transplantation [ISHLT] grade 0; 22.4 +/- 1.7 ng/liter). Mean troponin T concentrations increased in parallel with the severity of graft rejection (ISHLT grade 1: 27.8 +/- 1.8 ng/liter; grade 2: 33.2 +/- 2.7 ng/liter; grade 3A: 54.6 +/- 6.5 ng/liter; grade 3B and 4: 105.4 +/- 53.7 ng/liter; p < 0.001 for grades 3 and 4 vs. grades 0 and 1). The proportion of positive samples also increased in parallel with rejection severity, reaching 100% in rejections of grade 3B and 4. Sensitivity and specificity for the detection of significant graft rejection (ISHLT grade 3/4) were 80.4% and 61.8%, respectively. The negative predictive value was most remarkable with 96.2%. Intraindividual longitudinal analysis of troponin T levels and biopsy results in 15 patients during long-term follow-up confirmed these findings. CONCLUSIONS: The present data demonstrate that acute allograft rejection after human heart transplantation is often associated with increased serum concentrations of troponin T. All cases of serious forms of graft rejection would have been detected before the development of clinical symptoms. Measurement of troponin T levels may become a useful ancillary parameter for noninvasive rejection diagnosis, being most valuable in the exclusion of severe cardiac graft rejection.

Cytomegalovirus infection of vascular cells induces expression of pro-inflammatory adhesion molecules by paracrine action of secreted interleukin-1beta.

BACKGROUND: Infection with human cytomegalovirus (HCMV) has been associated with vascular disease processes such as vascular allograft rejection, transplantation vasculopathy, restenosis after angioplasty, and native atherosclerosis. To elucidate underlying pathomechanisms, the effect of acute HCMV infection on the expression of pro-inflammatory adhesion molecules on human umbilical vein endothelial cells (HUVEC) and human vascular smooth muscle cells (hvSMC) was examined. METHODS AND RESULTS: Cells were infected in vitro with clinical strains of HCMV and the resulting changes in adhesion molecule expression were quantified by histology and flow cytometric analysis. On HUVEC, surface expression of vascular cell adhesion molecule-1 and E-selectin was induced de novo on HCMV infection and intercellular adhesion molecule-1 expression was increased by >200%. On hvSMC, intercellular adhesion molecule-1 surface expression induced de novo, although vascular cell adhesion molecule-1 and E-selectin were not changed. Expression of major histocompatibility complex (MHC) class II, lymphocyte-function associated antigen 3 (LFA-3; CD58), and CD40 was not altered by HCMV infection in either cell type. In partially infected cultures, up-regulation of surface molecules also occurred on noninfected cells, suggesting a paracrine mechanism via a soluble factor. Expression of surface molecules could be enhanced in noninfected HUVEC and hvSMC by incubation with virus-free conditioned supernatant from HCMV-infected cells or by coincubation in transwells with infected cells. The responsible agent could be identified as IL- interleukin- (IL) 1beta by detection of de novo secretion of IL-1beta by HCMV-infected cells and by prevention of adhesion molecule up-regulation after addition of an IL-1-converting enzyme inhibitor or IL-1 receptor antagonist. Surface molecule up-regulation could be suppressed by UV inactivation of virus, but not by treatment of cell cultures with inhibitors of viral replication (ganciclovir). CONCLUSION: We propose that HCMV infection induces IL-1beta release and subsequent up-regulation of pro-inflammatory adhesion molecules on noninfected neighboring cells through a paracrine mechanism. This may lead to local potentiation of the inflammatory effects of HCMV infection, not amenable to current therapeutic antiviral strategies.

Differential immune response to influenza and pneumococcal vaccination in immunosuppressed patients after heart transplantation.

INTRODUCTION: Patients after solid organ transplantation are at an increased risk for microbial infections. Due to therapeutic immunosuppression, the response to active immunizations may be reduced. The serological efficacy of pneumococcal and influenza vaccination was studied in heart transplant recipients. PATIENTS AND METHODS: Sixteen patients over 1 year after heart transplantation and control patients were immunized with a 23-valent pneumococcal vaccine and a triple-split influenza vaccine. Pre- and postvaccinal antibody titers were serologically determined, including quantitation of specific antibodies against nine pneumococcal serotypes. RESULTS: Both vaccines were well tolerated without systemic reactions or infectious complications. Median postvaccinal pneumococcal antibody titers in the transplant patients were comparable to controls (5513 U/ml, range: 694-41007, vs. 5490 U/ml, range: 1088-38042; P=NS); vaccination was successful in 23/23 (100%) of controls and in 15/16 (94% plus 1 borderline positive case) of the transplant recipients. Specific antibody titers were similar for eight of nine serotypes; only the immune response against serotype 3 was reduced after transplantation. The efficacy of influenza vaccination was significantly impaired in transplant patients against all three virus strains (62% vs. 97%, P<0.01/50% vs. 94%, P<0.001/37% vs. 80%, P<0.01), but 9/16 (56%) of patients still showed a sufficient immune response to two out of three virus strains. No clinical or demographic predictors of successful vaccination could be established. CONCLUSIONS: Pneumococcal vaccination under cyclosporine-based immunosuppression after heart transplantation is safe and equally effective as in healthy controls. In contrast, the immune response to influenza vaccination is significantly reduced, although not completely abolished. This differential response might be accounted for by T cell-independent antibody production against polysaccharide antigens contained in the pneumococcal vaccine.

Prolonged allograft survival but no tolerance induction by modulating CD28 antibody JJ319 after high-responder rat heart transplantation.

BACKGROUND: Allograft rejection depends on T cell immune responses requiring antigen recognition and costimulatory signals through accessory T cell receptors, including CD28. Inhibition of CD28 signaling with a CTLA-4-immunoglobulin (Ig) fusion protein has resulted in immunosuppression and occasional T cell anergy in mouse transplant models, but not in rats. Because this approach also inhibits a potentially tolerizing signal through CTLA-4, selective blockade of CD28 ligation might induce more profound immunosuppression and transplant tolerance. METHODS: The effects of escalating doses of the rat CD28 monoclonal antibody JJ319 on allograft survival were studied after vascularized heterotopic heart transplantation in a high responder strain combination (DA to Lewis). CD28 antigen modulation and circulating antibody levels were monitored by flow cytometry. RESULTS: CD28 antibody JJ319 markedly prolonged cardiac graft survival compared with untreated controls (7 days, range: 6-8). A strictly dose-dependent increase in median graft survival time was demonstrated with a maximum of 36 days (range: 30-40; p <0.001) after the administration of 8 x 1 mg JJ319 i.p. (days -1 to +6 before/after transplantation). However, indefinite graft survival and tolerance could not be induced by JJ319 treatment. At the maximal dose, flow cytometry showed complete down modulation of the CD28 receptor for 10-14 days without T cell depletion in close temporal relation to antibody presence in serum. In vitro, CD28-modulated T cells showed significantly reduced responses to activation. CONCLUSIONS: CD28 antibody JJ319 induces profound immunosuppression after rat heart transplantation, however without development of transplant tolerance. The underlying mechanism seems to be receptor modulation during primary alloantigen recognition. While still potentially applicable clinically, there are no qualitative or quantitative differences to the treatment with CTLA-4/lg or the blockade of CD2 or LFA-1, as reported elsewhere. Thus, a CD28-modulating approach seems not to allow therapeutic exploitation of a tolerizing signal delivered by CTLA-4 but may still be clinically applicable, especially in combined immune interventions.

Endothelin plasma levels in acute graft rejection after heart transplantation.

BACKGROUND: Endothelin is an oligopeptide of endothelial origin with potent vasoconstrictive and mitogenic properties, implicated in the pathogenesis of cyclosporine-induced hypertension, graft vasculopathy, and renal failure. Experimental animal data suggest a role for endothelin in allograft rejection also. METHODS: To determine the role of endothelin in acute graft rejection after heart transplantation, we determined endothelin plasma levels in 165 blood samples from 79 cardiac allograft recipients (2 to 81 months after the operation) with normal graft function and correlated our findings with the histologic severity of acute graft rejection according to International Society for Heart and Lung Transplantation grading. For comparison endothelin levels were determined in 30 healthy controls and in 22 early postoperative transplant recipients (< 2 months after the operation). RESULTS: Endothelin plasma levels were significantly higher in transplant recipients than in controls (early postoperative: 7.97 = 7.53 pg/ml; late postoperative: 3.68 +/- 1.72 pg/ml; controls: 1.55 +/- 0.89 pg/ml). Endothelin plasma levels were not significantly different between groups of rejection grades 0 to 4. In the comparison of two groups of no rejection or lower (International Society for Heart and Lung Transplantation grade 0 and 1, n = 134) and higher (International Society for Heart and Lung Transplantation grade > or = 2, n = 31) rejection severity or comparing patients requiring rejection therapy (n = 20) with those not requiring therapy (n = 145), endothelin levels did not differ significantly between the groups. In 22 patients with three to six available consecutive biopsy scores and endothelin levels, intraindividual longitudinal analysis did also not show any significant correlation. The only positive correlation of endothelin levels with other laboratory parameters was found with serum creatinine concentrations (p < 0.001). In the early postoperative recipients, no correlation of endothelin plasma levels with rejection severity was seen; furthermore the only significant association was found with time after operation. CONCLUSIONS: In this study endothelin plasma levels were not influenced by acute allograft rejection after heart transplantation. Therefore endothelin levels do not appear to be a useful marker for noninvasive rejection diagnosis. Furthermore, a relevant pathogenetic role of endothelin in the rejection process cannot be derived from these data.

Adjuvant treatment with ursodeoxycholic acid may reduce the incidence of acute cardiac allograft rejection.

BACKGROUND: The nontoxic bile acid, ursodeoxycholic acid (UDCA), is an effective drug for the treatment of different cholestatic conditions. Furthermore, an immunomodulatory capacity of UDCA has been reported in vitro, as well as in vivo, in different immune-mediated liver diseases and after liver transplantation. METHODS: In this retrospective study, the influence of UDCA on heart transplant rejection was investigated in 21 cardiac allograft recipients receiving UDCA for cyclosporine-induced cholestasis (500 mg administered twice daily, start of therapy within the first postoperative month, duration >8 weeks). Thirty-one patients not receiving UDCA served as control subjects. All patients received triple-maintenance immunosuppression (cyclosporine, azathioprine, prednisolone). For quantitative comparison of rejection severity, the following score was applied: 0, no specific therapy; 1, temporary increase in oral steroids; 2, intravenous steroids; 3, ATG or OKT3 therapy. RESULTS: During the first 6 postoperative months, the number of acute rejection episodes requiring specific anti-rejection therapy was significantly lower in the UDCA group as compared with control subjects (1.38 +/- 1.36 vs 2.74 +/- 1.83 rejection episodes per patient, p = 0.005). The cumulative score was significantly lower in the UDCA group as compared with control subjects (2.38 +/- 2.29 vs 5.06 +/- 3.61, p = 0.004). CONCLUSIONS: These initial data indicate a beneficial effect of adjuvant UDCA treatment in the early phase after heart transplantation probably related to immunomodulating properties of UDCA, which may be used therapeutically after organ transplantation.

Transferral of extrathoracic donor neoplasm by the cardiac allograft.

The transference of neoplasm from the donor to the recipient is a rare but recognized complication of organ transplantation. It has been reported after kidney transplantation from cadaver donors. We report a case in which an extrathoracic tumor was transmitted by the donor heart. The donor heart was harvested from a 46-year-old local donor and immediately transplanted to a 62-year-old female recipient. While implantation was performed, a hypernephroma was detected in the multiorgan donor. The ongoing heart transplantation could not be stopped. Four weeks after operation, the patient was discharged from the hospital. During the first year after transplantation, the clinical course was uneventful. One year after operation, the patient was admitted to the hospital with symptoms of weakness and fever. A right facial hemiparesis occurred, and a soft tumor was palpable subcutaneously in the right supraorbital region. Histologic examination revealed a malignant tumor with characteristics identical to the donor hypernephroma. In spite of chemotherapy and radiation therapy, dramatic tumor progression occurred with multiorgan metastases, which led to the death of the patient 2 months after admission.