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Sample records for antibody mediated rejection

  1. Mechanisms involved in antibody- and complement-mediated allograft rejection

    OpenAIRE

    Wasowska, Barbara A.

    2010-01-01

    Antibody-mediated rejection has become critical clinically because this form of rejection is usually unresponsive to conventional anti-rejection therapy, and therefore, it has been recognized as a major cause of allograft loss. Our group developed experimental animal models of vascularized organ transplantation to study pathogenesis of antibody- and complement-mediated endothelial cell injury leading to graft rejection. In this review, we discuss mechanisms of antibody-mediated graft rejectio...

  2. Current perspectives on antibody-mediated rejection after lung transplantation

    Directory of Open Access Journals (Sweden)

    Witt CA

    2014-10-01

    Full Text Available Chad A Witt, Ramsey R Hachem Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, Washington University School of Medicine, Saint Louis, MO, USA Abstract: The role of donor-specific antibodies (DSA to human leukocyte antigens and the burden of antibody-mediated rejection (AMR in lung transplantation remain enigmatic. Over the past several years, evidence has been emerging that humoral immunity plays an important role in the development of both acute and chronic lung allograft dysfunction (CLAD. Multiple case reports and case series have identified lung allograft recipients with clinical findings consistent with acute AMR. However, there is currently no widely accepted definition for AMR in lung transplantation, and this has been a significant barrier to furthering our understanding of this form of rejection. Nonetheless, the development of DSA after transplantation has consistently been identified as an independent risk factor for persistent and high-grade acute cellular rejection and CLAD. This has raised the possibility that chronic AMR may be a distinct phenotype of CLAD although evidence supporting this paradigm is still lacking. Additionally, antibodies to lung-restricted self-antigens (collagen V and K-α 1 tubulin have been associated with primary graft dysfunction early and the development of CLAD late after transplantation, and emerging evidence underscores significant interactions between autoimmunity and alloimmunity after transplantation. There is currently an active International Society for Heart and Lung Transplantation working group that is developing an operational definition for AMR in lung transplantation. This will be critical to improve our understanding of this form of rejection and conduct clinical trials to identify optimal treatment strategies. This review will summarize the literature on DSA and AMR in lung transplantation and discuss the impact of antibodies to self-antigens on lung

  3. Treatment of Antibody-Mediated Rejection in Kidney Transplantation

    Directory of Open Access Journals (Sweden)

    Magdalena Durlik

    2013-07-01

    Full Text Available Antibody-mediated rejection (AMR is a relatively rare but severe complication in kidney transplantation associated with increased risk of graft loss. Diagnosis of acute and chronic AMR is based on typical histological hallmarks, deposition of C4d in peritubular capillaries and presence of donor-specific antibodies (DSA. Many novel and attractive treatment options have become available in recent years: antibody removal and production inhibition (plasmapheresis, IVIg, B cell depletion (rituximab, plasma cell depletion and apoptosis (bortezomib, and complement activation inhibition (eculizumab. Standard therapy is based on PP and IVIg. Preliminary results with new agents are encouraging but require randomised clinical trials and long-term follow-up.

  4. Antibody-Mediated Rejection: Pathogenesis, Prevention, Treatment, and Outcomes

    Directory of Open Access Journals (Sweden)

    Olivia R. Blume

    2012-01-01

    Full Text Available Antibody-mediated rejection (AMR is a major cause of late kidney transplant failure. It is important to have an understanding of human-leukocyte antigen (HLA typing including well-designed studies to determine anti-MHC-class-I-related chain A (MICA and antibody rejection pathogenesis. This can allow for more specific diagnosis and treatment which may improve long-term graft function. HLA-specific antibody detection prior to transplantation allows one to help determine the risk for AMR while detection of DSA along with a biopsy confirms it. It is now appreciated that biopsy for AMR does not have to include diffuse C4d, but does require a closer look at peritubular capillary microvasculature. Although plasmapheresis (PP is effective in removing alloantibodies (DSAs from the circulation, rebound synthesis of alloantibodies can occur. Splenectomy is used in desensitization protocols for ABO incompatible transplants as well as being found to treat AMR refractory to conventional treatment. Also used are agents targeted for plasma cells, B cells, and the complement cascade which are bortezomib rituximab and eculizumab, respectively.

  5. B cells mediate chronic allograft rejection independently of antibody production.

    Science.gov (United States)

    Zeng, Qiang; Ng, Yue-Harn; Singh, Tripti; Jiang, Ke; Sheriff, Khaleefathullah A; Ippolito, Renee; Zahalka, Salwa; Li, Qi; Randhawa, Parmjeet; Hoffman, Rosemary A; Ramaswami, Balathiripurasundari; Lund, Frances E; Chalasani, Geetha

    2014-03-01

    Chronic rejection is the primary cause of long-term failure of transplanted organs and is often viewed as an antibody-dependent process. Chronic rejection, however, is also observed in mice and humans with no detectable circulating alloantibodies, suggesting that antibody-independent pathways may also contribute to pathogenesis of transplant rejection. Here, we have provided direct evidence that chronic rejection of vascularized heart allografts occurs in the complete absence of antibodies, but requires the presence of B cells. Mice that were deficient for antibodies but not B cells experienced the same chronic allograft vasculopathy (CAV), which is a pathognomonic feature of chronic rejection, as WT mice; however, mice that were deficient for both B cells and antibodies were protected from CAV. B cells contributed to CAV by supporting splenic lymphoid architecture, T cell cytokine production, and infiltration of T cells into graft vessels. In chimeric mice, in which B cells were present but could not present antigen, both T cell responses and CAV were markedly reduced. These findings establish that chronic rejection can occur in the complete absence of antibodies and that B cells contribute to this process by supporting T cell responses through antigen presentation and maintenance of lymphoid architecture.

  6. B cells mediate chronic allograft rejection independently of antibody production.

    Science.gov (United States)

    Zeng, Qiang; Ng, Yue-Harn; Singh, Tripti; Jiang, Ke; Sheriff, Khaleefathullah A; Ippolito, Renee; Zahalka, Salwa; Li, Qi; Randhawa, Parmjeet; Hoffman, Rosemary A; Ramaswami, Balathiripurasundari; Lund, Frances E; Chalasani, Geetha

    2014-03-01

    Chronic rejection is the primary cause of long-term failure of transplanted organs and is often viewed as an antibody-dependent process. Chronic rejection, however, is also observed in mice and humans with no detectable circulating alloantibodies, suggesting that antibody-independent pathways may also contribute to pathogenesis of transplant rejection. Here, we have provided direct evidence that chronic rejection of vascularized heart allografts occurs in the complete absence of antibodies, but requires the presence of B cells. Mice that were deficient for antibodies but not B cells experienced the same chronic allograft vasculopathy (CAV), which is a pathognomonic feature of chronic rejection, as WT mice; however, mice that were deficient for both B cells and antibodies were protected from CAV. B cells contributed to CAV by supporting splenic lymphoid architecture, T cell cytokine production, and infiltration of T cells into graft vessels. In chimeric mice, in which B cells were present but could not present antigen, both T cell responses and CAV were markedly reduced. These findings establish that chronic rejection can occur in the complete absence of antibodies and that B cells contribute to this process by supporting T cell responses through antigen presentation and maintenance of lymphoid architecture. PMID:24509079

  7. Posttransplantation antibody mediated rejection: new insights into mechanism, treatment and protective strategies

    Institute of Scientific and Technical Information of China (English)

    MAO You-ying; CHEN Jiang-hua

    2011-01-01

    @@ Acute antibody mediated rejection (AMR) is receiving more and more attention, which is mediated by different mechanisms from T cell mediated rejection, thereby requiring other approaches to prevention and treatment. Preexisting alloantibodies and pre-transplant sensitization are important risk factors for development of acute AMR early after renal transplantation.

  8. The Complement System and Antibody-Mediated Transplant Rejection.

    Science.gov (United States)

    Stites, Erik; Le Quintrec, Moglie; Thurman, Joshua M

    2015-12-15

    Complement activation is an important cause of tissue injury in patients with Ab-mediated rejection (AMR) of transplanted organs. Complement activation triggers a strong inflammatory response, and it also generates tissue-bound and soluble fragments that are clinically useful markers of inflammation. The detection of complement proteins deposited within transplanted tissues has become an indispensible biomarker of AMR, and several assays have recently been developed to measure complement activation by Abs reactive to specific donor HLA expressed within the transplant. Complement inhibitors have entered clinical use and have shown efficacy for the treatment of AMR. New methods of detecting complement activation within transplanted organs will improve our ability to diagnose and monitor AMR, and they will also help guide the use of complement inhibitory drugs.

  9. The Complement System and Antibody-Mediated Transplant Rejection.

    Science.gov (United States)

    Stites, Erik; Le Quintrec, Moglie; Thurman, Joshua M

    2015-12-15

    Complement activation is an important cause of tissue injury in patients with Ab-mediated rejection (AMR) of transplanted organs. Complement activation triggers a strong inflammatory response, and it also generates tissue-bound and soluble fragments that are clinically useful markers of inflammation. The detection of complement proteins deposited within transplanted tissues has become an indispensible biomarker of AMR, and several assays have recently been developed to measure complement activation by Abs reactive to specific donor HLA expressed within the transplant. Complement inhibitors have entered clinical use and have shown efficacy for the treatment of AMR. New methods of detecting complement activation within transplanted organs will improve our ability to diagnose and monitor AMR, and they will also help guide the use of complement inhibitory drugs. PMID:26637661

  10. Late antibody-mediated rejection after ABO-incompatible kidney transplantation during Gram-negative sepsis

    NARCIS (Netherlands)

    A. de Weerd (Annelies); A.G. Vonk (Alieke); H. van der Hoek (Hans); M. van Groningen (Marian); W. Weimar (Willem); M.G.H. Betjes (Michiel); M. Agteren (Madelon)

    2014-01-01

    textabstractBackground: The major challenge in ABO-incompatible transplantation is to minimize antibody-mediated rejection. Effective reduction of the anti-ABO blood group antibodies at the time of transplantation has made ABO-incompatible kidney transplantation a growing practice in our hospital an

  11. Recombinant human C1-inhibitor prevents acute antibody-mediated rejection in alloimmunized baboons

    NARCIS (Netherlands)

    Tillou, Xavier; Poirier, Nicolas; Le Bas-Bernardet, Stephanie; Hervouet, Jeremy; Minault, David; Renaudin, Karine; Vistoli, Fabio; Karam, Georges; Daha, Mohamed; Soulillou, Jean Paul; Blancho, Gilles

    2010-01-01

    Acute antibody-mediated rejection is an unsolved issue in transplantation, especially in the context of pretransplant immunization. The deleterious effect of preformed cytotoxic anti-HLA antibodies through complement activation is well proven, but very little is known concerning complement blockade

  12. Long-term experience of plasmapheresis in antibody-mediated rejection in renal transplantation.

    LENUS (Irish Health Repository)

    Brown, C M

    2009-11-01

    Antibody-mediated rejection (AMR) continues to pose a serious challenge in renal transplantation with potentially devastating consequences. Treatment options for this condition include plasmapheresis, high-dose intravenous immunoglobulin (IVIG), plasmapheresis with low-dose IVIG, and the use of rituximab (anti-CD20 chimeric antibody). We previously reported on the short-term outcome of plasmapheresis as a rescue therapy for AMR in our centre. We now report on the long-term follow up.

  13. Chronic alloantibody mediated rejection

    OpenAIRE

    Smith, R. Neal; Colvin, Robert B.

    2011-01-01

    Alloantibodies clearly cause acute antibody mediated rejection, and all available evidence supports their pathogenic etiology in the development of chronic alloantibody mediated rejection (CAMR). But the slow evolution of this disease, the on-going immunosuppression, the variations in titer of alloantibodies, and variation in antigenic targets all complicate identifying which dynamic factors are most important clinically and pathologically. This review highlights the pathological factors rela...

  14. INTRAVENOUS IMMUNOGLOBULIN ADMINISTRATION FOR DESENSITIZATION BEFORE RENAL TRANSPLANTATION AND MANAGING ANTIBODY-MEDIATED REJECTION

    Directory of Open Access Journals (Sweden)

    A. I. Sushkov

    2011-01-01

    Full Text Available Much attention has been placed recently in transplantation in highly HLA-sensitized patients. In attempts to remove these antibodies and enable successful renal transplantation, several approaches have been developed. Intravenous immunoglobulin (IVIG was found to be effective in the treatment of autoimmune and inflammatory disorders (e. g. Kawasaki disease, Guillain-Barre syndrome. Recently, a beneficial effect of IVIG on the reduc- tion of anti-HLA antibodies was described. The anti-inflammatory effect of IVIG provides hopeful opportunities in antibody-mediated rejection (AMR management. There are several protocols of IVIG administration for pre-transplant desensitization and AMR treatment: high-dose IVIG, low-dose IVIG + plasmapheresis, IVIG + plasmapheresis + rituximab. These advancements have enabled transplantation in patients previously considered untransplantable and in concert with new diagnostic techniques has resulted in new approaches to management of AMR. 

  15. CHALLENGES IN TREATMENT OF RENAL GRAFT ACUTE ANTIBODY-MEDIATED REJECTION

    Directory of Open Access Journals (Sweden)

    A. I. Sushkov

    2016-01-01

    Full Text Available Diagnostic criteria and treatment protocols for acute antibody-mediated rejection (AMR of kidney allograft remain controversial. We report the case of early severe AMR after primary kidney transplantation. The graft removal was considered in the absence of treatment efficacy and in the presence of systemic infl ammatory response syndrome. However, at surgery the graft looked normal and it was not removed. The repeated treatment course (plasmapheresis, antithymocyte globulin, intravenous immunoglobulin and rituximab was effective. The patient has good and stable graft function in 1 year after transplantation. 

  16. Utility of Double Filtration Plasmapheresis in Acute Antibody Mediated Renal Allograft Rejection: Report of Three Cases

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    Yalçın SOLAK

    2011-09-01

    Full Text Available Plasmapheresis is an extracorporeal procedure, which is often employed to rapidly lower circulating titers of autoantibodies, immune complexes or toxins. There are two types of plasmapheresis namely, regular plasmapheresis (RPP by centrifugation and membrane filtration, and double filtration plasmapheresis (DFPP which is a special form of membrane filtration in which two membranes called as plasma separator and plasma fractionator are employed to filter macromolecules more selectively. DFPP have several advantages over RP. Despite widespread utilization of DFPP in the setting of ABO blood group incompatible kidney transplantation, there is no report regarding DFPP in patients with antibody mediated acute renal allograft rejection who are good candidates for beneficial effects of DFPP. Here we report three renal transplant recipients in whom DFPP was applied as a component of anti-rejection treatment regimen.

  17. A systematic review of the role of C4d in the diagnosis of acute antibody-mediated rejection.

    Science.gov (United States)

    Sapir-Pichhadze, Ruth; Curran, Simon P; John, Rohan; Tricco, Andrea C; Uleryk, Elizabeth; Laupacis, Andreas; Tinckam, Kathryn; Sis, Banu; Beyene, Joseph; Logan, Alexander G; Kim, S Joseph

    2015-01-01

    In this study, we conducted a systematic review of the literature to re-evaluate the role of C4d in the diagnosis of acute antibody-mediated rejection of kidney allografts. Electronic databases were searched until September 2013. Eligible studies allowed derivation of diagnostic tables for the performance of C4d by immunofluorescence or immunohistochemistry with comparison to histopathological features of acute antibody-mediated rejection and/or donor-specific antibody (DSA) assays. Of 3492 unique abstracts, 29 studies encompassing 3485 indication and 868 surveillance biopsies were identified. Assessment of C4d by immunofluorescence and immunohistochemistry exhibited slight to moderate agreement with glomerulitis, peritubular capillaritis, solid-phase DSA assays, DSA with glomerulitis, and DSA with peritubular capillaritis. The sensitivity and specificity of C4d varied as a function of C4d and comparator test thresholds. Prognostically, the presence of C4d was associated with inferior allograft survival compared with DSA or histopathology alone. Thus, our findings support the presence of complement-dependent and -independent phenotypes of acute antibody-mediated rejection. Whether the presence of C4d in combination with histopathology or DSA should be considered for the diagnosis of acute antibody-mediated rejection warrants further study. PMID:24827778

  18. A type I interferon signature characterizes chronic antibody-mediated rejection in kidney transplantation.

    Science.gov (United States)

    Rascio, Federica; Pontrelli, Paola; Accetturo, Matteo; Oranger, Annarita; Gigante, Margherita; Castellano, Giuseppe; Gigante, Maddalena; Zito, Anna; Zaza, Gianluigi; Lupo, Antonio; Ranieri, Elena; Stallone, Giovanni; Gesualdo, Loreto; Grandaliano, Giuseppe

    2015-09-01

    Chronic antibody-mediated rejection (CAMR) represents the main cause of kidney graft loss. To uncover the molecular mechanisms underlying this condition, we characterized the molecular signature of peripheral blood mononuclear cells (PBMCs) and, separately, of CD4(+) T lymphocytes isolated from CAMR patients, compared to kidney transplant recipients with normal graft function and histology. We enrolled 29 patients with biopsy-proven CAMR, 29 stable transplant recipients (controls), and 8 transplant recipients with clinical and histological evidence of interstitial fibrosis/tubular atrophy. Messenger RNA and microRNA profiling of PBMCs and CD4(+) T lymphocytes was performed using Agilent microarrays in eight randomly selected patients per group from CAMR and control subjects. Results were evaluated statistically and by functional pathway analysis (Ingenuity Pathway Analysis) and validated in the remaining subjects. In PBMCs, 45 genes were differentially expressed between the two groups, most of which were up-regulated in CAMR and were involved in type I interferon signalling. In the same patients, 16 microRNAs were down-regulated in CAMR subjects compared to controls: four were predicted modulators of six mRNAs identified in the transcriptional analysis. In silico functional analysis supported the involvement of type I interferon signalling. To further confirm this result, we investigated the transcriptomic profiles of CD4(+) T lymphocytes in an independent group of patients, observing that the activation of type I interferon signalling was a specific hallmark of CAMR. In addition, in CAMR patients, we detected a reduction of circulating BDCA2(+) dendritic cells, the natural type I interferon-producing cells, and their recruitment into the graft along with increased expression of MXA, a type I interferon-induced protein, at the tubulointerstitial and vascular level. Finally, interferon alpha mRNA expression was significantly increased in CAMR compared to control

  19. Outcome of subclinical antibody-mediated rejection in kidney transplant recipients with preformed donor-specific antibodies.

    Science.gov (United States)

    Loupy, A; Suberbielle-Boissel, C; Hill, G S; Lefaucheur, C; Anglicheau, D; Zuber, J; Martinez, F; Thervet, E; Méjean, A; Charron, D; Duong van Huyen, J P; Bruneval, P; Legendre, C; Nochy, D

    2009-11-01

    This study describes clinical relevance of subclinical antibody-mediated rejection (SAMR) in a cohort of 54 DSA-positive kidney transplant recipients receiving a deceased donor. In 3 months screening biopsies, 31.1% of patients met the criteria of SAMR. A total of 48.9% had an incomplete form of SAMR (g+/ptc+/C4d-negative) whereas 20% had no humoral lesions. Patients with SAMR at 3 months had at 1 year: a higher C4d score, ptc score, and arteriosclerosis score, higher rate of IFTA (100% vs. 33.3%, p SAMR. Patients with SAMR at 3 months exhibited at 1 year a higher class II MFImax-DSA and a lower mGFR compared to patients without SAMR (39.2 +/- 13.9 vs. 61.9 +/- 19.2 mL/min/1.73 m(2) respectively, p SAMR at 3 months developed more ptc and IFTA lesions, and lower GFR at 1 year in comparison to biopsies without humoral lesions. SAMR is a frequent entity in KTR with preexisting DSAs and promotes subsequent GFR impairment and development of chronic AMR. C4d-negative SAMR patients displayed an intermediate course between the no-SAMR group and the C4d+ SAMR group. Screening biopsies may be useful to recognize patients more likely to develop SAMR. PMID:19775320

  20. The 2013 International Society for Heart and Lung Transplantation Working Formulation for the standardization of nomenclature in the pathologic diagnosis of antibody-mediated rejection in heart transplantation

    DEFF Research Database (Denmark)

    Berry, Gerald J; Burke, Margaret M; Andersen, Claus Yding;

    2013-01-01

    During the last 25 years, antibody-mediated rejection of the cardiac allograft has evolved from a relatively obscure concept to a recognized clinical complication in the management of heart transplant patients. Herein we report the consensus findings from a series of meetings held between 2010-20...

  1. Markers of Endothelial-to-Mesenchymal Transition: Evidence for Antibody-Endothelium Interaction during Antibody-Mediated Rejection in Kidney Recipients.

    Science.gov (United States)

    Xu-Dubois, Yi-Chun; Peltier, Julie; Brocheriou, Isabelle; Suberbielle-Boissel, Caroline; Djamali, Arjang; Reese, Shannon; Mooney, Nuala; Keuylian, Zela; Lion, Julien; Ouali, Nacéra; Levy, Pierre P; Jouanneau, Chantal; Rondeau, Eric; Hertig, Alexandre

    2016-01-01

    Antibody-mediated rejection (ABMR) is a leading cause of allograft loss. Treatment efficacy depends on accurate diagnosis at an early stage. However, sensitive and reliable markers of antibody-endothelium interaction during ABMR are not available for routine use. Using immunohistochemistry, we retrospectively studied the diagnostic value of three markers of endothelial-to-mesenchymal transition (EndMT), fascin1, vimentin, and heat shock protein 47, for ABMR in 53 renal transplant biopsy specimens, including 20 ABMR specimens, 24 cell-mediated rejection specimens, and nine normal grafts. We validated our results in an independent set of 74 unselected biopsy specimens. Endothelial cells of the peritubular capillaries in grafts with ABMR expressed fascin1, vimentin, and heat shock protein 47 strongly, whereas those from normal renal grafts did not. The level of EndMT marker expression was significantly associated with current ABMR criteria, including capillaritis, glomerulitis, peritubular capillary C4d deposition, and donor-specific antibodies. These markers allowed us to identify C4d-negative ABMR and to predict late occurrence of disease. EndMT markers were more specific than capillaritis for the diagnosis and prognosis of ABMR and predicted late (up to 4 years after biopsy) renal graft dysfunction and proteinuria. In the independent set of 74 renal graft biopsy specimens, the EndMT markers for the diagnosis of ABMR had a sensitivity of 100% and a specificity of 85%. Fascin1 expression in peritubular capillaries was also induced in a rat model of ABMR. In conclusion, EndMT markers are a sensitive and reliable diagnostic tool for detecting endothelial activation during ABMR and predicting late loss of allograft function.

  2. Antibody-Mediated Rejection of the Heart in the Setting of Autoimmune Demyelinating Polyneuropathy: A Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Kathryn J. Lindley

    2012-01-01

    Full Text Available Background. Antibody-mediated rejection (AMR is caused by the production of donor-specific antibodies (DSA which lead to allograft injury in part via complement activation. The inflammatory demyelinating polyneuropathies (IDP are inflammatory disorders of the nervous system, involving both cellular and humoral immune mechanisms directed against myelin. Case Report. A 58-year-old man five years after heart transplant presented with progressive dyspnea, imbalance, dysphagia, and weakness. Nerve conduction studies and electromyogram were consistent with IDP. Plasmapheresis and high-dose steroids resulted in improvement in neurologic symptoms. Within two weeks, he was readmitted with anasarca and acute renal failure, requiring intravenous furosemide and inotropic support. Echocardiogram and right heart catheterization revealed reduced cardiac function and elevated filling pressures. DSA was positive against HLA DR53, and endomyocardial biopsy revealed grade 1R chronic inflammation, with strong capillary endothelial immunostaining for C4d. Plasmapheresis and intravenous immunoglobulin (IVIG were initiated. His anasarca and renal failure subsequently resolved, echocardiogram showed improved function off inotropes, and anti-DR53 MFI was reduced by 57%. Conclusions. This is an example of a single immune-mediated process causing concurrent IDP and AMR. The improvement in cardiac function and neurologic symptoms with plasmapheresis, IVIG, and high-dose steroids argues for a unifying antibody-mediated mechanism.

  3. HLA-C antibodies in women with recurrent miscarriage suggests that antibody mediated rejection is one of the mechanisms leading to recurrent miscarriage.

    Science.gov (United States)

    Meuleman, T; van Beelen, E; Kaaja, R J; van Lith, J M M; Claas, F H J; Bloemenkamp, K W M

    2016-08-01

    HLA-C is the only polymorphic classical HLA I antigen expressed on trophoblast cells. It is known that higher incidence of C4d deposition on trophoblast cells is present in women with recurrent miscarriage. C4d is a footprint of antibody-mediated classical complement activation. Therefore, this study hypothesize that antibodies against HLA-C may play a role in the occurrence of unexplained consecutive recurrent miscarriage. Present case control study compared the incidence of HLA-C specific antibodies in 95 women with at least three consecutive miscarriages and 105 women with uneventful pregnancy. In the first trimester of the next pregnancy, presence and specificity of HLA antibodies were determined and their complement fixing ability. The incidence of HLA antibodies was compared with uni- and multivariate logistic regression models adjusting for possible confounders. Although in general a higher incidence of HLA antibodies was found in women with recurrent miscarriage 31.6% vs. in control subjects 9.5% (adjusted OR 4.3, 95% CI 2.0-9.5), the contribution of antibodies against HLA-C was significantly higher in women with recurrent miscarriage (9.5%) compared to women with uneventful pregnancy (1%) (adjusted OR 11.0, 95% CI 1.3-89.0). In contrast to the control group, HLA-C antibodies in the recurrent miscarriage group were more often able to bind complement. The higher incidence of antibodies specific for HLA-C in women with recurrent miscarriage suggests that HLA-C antibodies may be involved in the aetiology of unexplained consecutive recurrent miscarriage. PMID:27172837

  4. SUCCESSFUL APPLICATION OF PERIPHERAL VENO-ARTERIAL EXTRACORPOREAL MEMBRANE OXYGENATION FOR CARDIAC ALLOGRAFT ANTIBODY-MEDIATED REJECTION WITH SEVERE HEMODYNAMIC COMPROMISE

    Directory of Open Access Journals (Sweden)

    V. N. Poptsov

    2015-01-01

    Full Text Available Introduction. Acute antibody-mediated rejection (AMR is one of the severe complications of early and late period after heart transplantation (HT. Only few case reports and studies presented of mechanical circulatory support (MCS application for refractory acute rejection causing hemodynamic compromise. Aim. We report the case of a woman with cardiogenic shock caused by severe AMR that was successfully treatment by peripheral venoarterial extracorporeal membrane oxygenation (VA ECMO. Material and methods. In december 2014, a 60-year-old woman with dilated cardiomyopathy was operated for HT. The patient had a good initial cardiac allograft function and no and was discharged from ICU on the 4th day after HT. 1st endomyocardial biopsy (EMB (the 7th day after HT showed absence of acute cellular and antibody-mediated rejection. On the 11th day after HT patient aggravated and presented clinical signs of life-threatening acute cardiac allograft dysfunction: arterial blood pressure 78/49/38 mm Hg, HR 111 in min, CVP 20 mm Hg, PAP 47/34/25 mm Hg, PCWP 25 mm Hg, CI 1.5 l/min/m2, adrenalin 110 ng/kg/min, dopamine 15 mcg/kg/min. ECG showed impairment of systolic left (LVEF 25% and right (RVEF 15% ventricle function, left and right ventricle diffuse hypokinesis, thickness of IVS, LV and RV wall 1.7, 1.4 and 0.8 cm, tricuspid and mitral valve regurgitation 2–3 degrees. EMB presented AMR. In conscience peripheral VA ECMO was installed. We used peripheral transcutaneous cannulation technique via femoral vessels – arterial cannula 15 F, venous cannula – 23 F, vascular catheter 14 G for anterograde leg’s perfusion. ACT 130–150 sec. AMR therapy included: methylprednisolon pulse-therapy (10 mg/kg for 5 day, IgG, plasmapheresis (No 7, rituximab. Results. Under MCS by VA ECMO we noted quick improvement of hemodynamic, metabolic homeostasis and organ functions. On the 6th day of VA ECMO (blood flow 1.8 l/min: arterial blood pressure 133/81/54 mm Hg, CVP 5 mm

  5. Acute Antibody-Mediated Rejection in Presence of MICA-DSA and Successful Renal Re-Transplant with Negative-MICA Virtual Crossmatch.

    Science.gov (United States)

    Ming, Yingzi; Hu, Juan; Luo, Qizhi; Ding, Xiang; Luo, Weiguang; Zhuang, Quan; Zou, Yizhou

    2015-01-01

    The presence of donor-specific alloantibodies (DSAs) against the MICA antigen results in high risk for antibody-mediated rejection (AMR) of a transplanted kidney, especially in patients receiving a re-transplant. We describe the incidence of acute C4d+ AMR in a patient who had received a first kidney transplant with a zero HLA antigen mismatch. Retrospective analysis of post-transplant T and B cell crossmatches were negative, but a high level of MICA alloantibody was detected in sera collected both before and after transplant. The DSA against the first allograft mismatched MICA*018 was in the recipient. Flow cytometry and cytotoxicity tests with five samples of freshly isolated human umbilical vein endothelial cells demonstrated the alloantibody nature of patient's MICA-DSA. Prior to the second transplant, a MICA virtual crossmatch and T and B cell crossmatches were used to identify a suitable donor. The patient received a second kidney transplant, and allograft was functioning well at one-year follow-up. Our study indicates that MICA virtual crossmatch is important in selection of a kidney donor if the recipient has been sensitized with MICA antigens.

  6. Acute Antibody-Mediated Rejection in Presence of MICA-DSA and Successful Renal Re-Transplant with Negative-MICA Virtual Crossmatch.

    Directory of Open Access Journals (Sweden)

    Yingzi Ming

    Full Text Available The presence of donor-specific alloantibodies (DSAs against the MICA antigen results in high risk for antibody-mediated rejection (AMR of a transplanted kidney, especially in patients receiving a re-transplant. We describe the incidence of acute C4d+ AMR in a patient who had received a first kidney transplant with a zero HLA antigen mismatch. Retrospective analysis of post-transplant T and B cell crossmatches were negative, but a high level of MICA alloantibody was detected in sera collected both before and after transplant. The DSA against the first allograft mismatched MICA*018 was in the recipient. Flow cytometry and cytotoxicity tests with five samples of freshly isolated human umbilical vein endothelial cells demonstrated the alloantibody nature of patient's MICA-DSA. Prior to the second transplant, a MICA virtual crossmatch and T and B cell crossmatches were used to identify a suitable donor. The patient received a second kidney transplant, and allograft was functioning well at one-year follow-up. Our study indicates that MICA virtual crossmatch is important in selection of a kidney donor if the recipient has been sensitized with MICA antigens.

  7. Antibody-mediated rejection after ABO-incompatible pediatric living donor liver transplantation for propionic acidemia: A case report.

    Science.gov (United States)

    Honda, Masaki; Sakamoto, Seisuke; Sakamoto, Rieko; Matsumoto, Shirou; Irie, Tomoaki; Uchida, Koushi; Shimata, Keita; Kawabata, Seiichi; Isono, Kaori; Hayashida, Shintaro; Yamamoto, Hidekazu; Endo, Fumio; Inomata, Yukihiro

    2016-09-01

    We herein present the case of a four-yr-old boy with PA who developed AMR after ABO-incompatible LDLT despite undergoing B cell desensitization using rituximab. Although the CD19+ lymphocyte count decreased to 0.1% nine days after the administration of rituximab, he developed a high fever which was accompanied by arthralgia due to a streptococcal infection 13 days after rituximab prophylaxis. After the clearance of the infection, he underwent ABO-incompatible LDLT 36 days after the administration of rituximab. The CD19+ lymphocyte count just prior to LDLT was 1.2%. He developed AMR five days after LDLT, and the antidonor-type IgM and IgG antibody titers increased to 1:1024 and 1:1024, respectively. He was treated by plasma exchange, IVIG, steroid pulse therapy, and rituximab re-administration; however, his liver dysfunction continued. Despite intensive treatment, he died due to complicated abdominal hernia, acute renal failure, and ARDS. This case suggests that a streptococcal infection may induce the activation of innate immune responses; thus, additional desensitization therapy should be considered prior to ABO-incompatible LDLT if B cell reactivation is suspected. PMID:27436684

  8. Antibody-mediated Xenograft Injury: Mechanisms and Protective Strategies

    OpenAIRE

    Pierson, Richard N.

    2009-01-01

    The use of porcine organs for clinical transplantation is a promising potential solution to the shortage of human organs. Preformed anti-pig antibody is the primary cause of hyperacute rejection, while elicited antibody can contribute to subsequent “delayed” xenograft rejection. This article will review recent progress to overcome antibody mediated xenograft rejection, through modification of the host immunity and use of genetically engineered pig organs.

  9. Decreased humoral antibody episodes of acute renal allograft rejection in recipients expressing the HLA-DQβ1*0202 allele.

    Science.gov (United States)

    Mannam, Venkat K R; Santos, Mark; Lewis, Robert E; Cruse, Julius M

    2012-10-01

    The present investigation was designed to show the effect of human leukocyte antigen (HLA) class II molecular allelic specificities in the recipient on the induction of humoral antibody rejection, identified by C4d peritubular capillary staining, as well as specific antibody identified by Luminex technology. Major histocompatibility complex (MHC) class II molecules are expressed on dendritic cells, macrophages, and B lymphocytes and they present antigenic peptides to CD4 positive T lymphocytes. Human renal peritubular and glomerular capillaries express class II MHC molecules upon activation. Expression of class II molecules on renal microvascular endothelial cells exposes them to possible interaction with specific circulating antibodies. We hypothesize that HLA-DQβ1*0202 expression in recipients decreases the likelihood of antibody-mediated renal allograft rejection. We found that 80% (=25) of DQ2 positive haplotype recipients failed to induce humoral antibody renal allograft rejection and 20% (n=25) of DQ2 positive haplotype recipients induced humoral antibody renal allograft rejection (p=0.008). By contrast, 48% (n=46) of DQ2 negative haplotype recipients failed to induce a humoral antibody component of renal allograft rejection and 52% (n=46) of DQ2 negative haplotype recipients induced humoral antibody-mediated renal allograft rejection. Our results suggest that recipients who express the DQβ1*0202 allele are less likely to induce a humoral antibody component of acute renal allograft rejection than are those expressing DQ1, DQ3, or DQ4 alleles. DQβ1*0202 allele expression in recipients could possibly be protective against acute humoral allograft rejection and might serve as a future criterion in recipient selection and in appropriate therapy for acute renal rejection episodes.

  10. Role of anti-vimentin antibodies in allograft rejection.

    Science.gov (United States)

    Rose, Marlene L

    2013-11-01

    Production of anti-vimentin antibodies (AVA) after solid organ transplantation are common. Although classically thought to be expressed mainly within the cytosol, recent evidence demonstrates that extracellular or cell surface expression of vimentin is not unusual. This review examines the evidence to assess whether AVA contribute to allograft pathology. Clinical studies suggest that AVA are associated with cardiac allograft vasculopathy in heart transplant recipients. Studies in non-human primates confirm that production of AVA after renal and heart transplantation are not inhibited by Cyclosporine. Experimental studies have demonstrated that mice pre-immunised with vimentin undergo accelerated acute rejection and vascular intimal occlusion of cardiac allografts. Adoptive transfer of hyperimmune sera containing AVA into B-cell-knock-out mice caused accelerated rejection of allografted hearts, this is clear evidence that antibodies to vimentin accelerate rejection. AVA act in concert with the alloimmune response and AVA do not damage syngeneic or native heart allografts. Confocal microscopy of allografted organs in vimentin immunised mice shows extensive expression of vimentin on endothelial cells, apoptotic leukocytes and platelet/leukocyte conjugates, co-localising with C4d. One explanation for the ability of AVA to accelerate rejection would be fixation of complement within the graft and subsequent pro-inflammatory effects; there may also be interactions with platelets within the vasculature.

  11. B-cell-mediated strategies to fight chronic allograft rejection

    Directory of Open Access Journals (Sweden)

    Ali H Dalloul

    2013-12-01

    Full Text Available Solid organs have been transplanted for decades. Since the improvement in graft selection and in medical and surgical procedures, the likelihood of graft function after one year is now close to 90%. Nonetheless even well-matched recipients continue to need medications for the rest of their lives hence adverse side effects and enhanced morbidity. Understanding Immune rejection mechanisms, is of increasing importance since the greater use of living-unrelated donors and genetically unmatched individuals. Chronic rejection is devoted to T-cells, however the role of B-cells in rejection has been appreciated recently by the observation that B-cell depletion improve graft survival. By contrast however, B-cells can be beneficial to the grafted tissue. This protective effect is secondary to either the secretion of protective antibodies or the induction of B-cells that restrain excessive inflammatory responses, chiefly by local provision of IL-10, or inhibit effector T-cells by direct cellular interactions. As a proof of concept B-cell-mediated infectious transplantation tolerance could be achieved in animal models, and evidence emerged that the presence of such B-cells in transplanted patients correlate with a favorable outcome. Among these populations, regulatory B-cells constitute a recently described population. These cells may develop as a feedback mechanism to prevent uncontrolled reactivity to antigens and inflammatory stimuli. The difficult task for the clinician, is to quantify the respective ratios and functions of tolerant vs effector B-cells within a transplanted organ, at a given time point in order to modulate B-cell-directed therapy. Several receptors at the B-cell membrane as well as signaling molecules, can now be targeted for this purpose. Understanding the temporal expansion of regulatory B-cells in grafted patients and the stimuli that activate them will help in the future to implement specific strategies aimed at fighting chronic

  12. Chronic Renal Allograft Dysfunction Antibody-Mediated: An Update

    Directory of Open Access Journals (Sweden)

    Maurizio Salvadori,

    2014-07-01

    Full Text Available This paper reviews the most important studies on chronic antibody-mediated rejection (cABMR, which is an important cause of late graft dysfunction after renal transplantation. Several antibodies seem to be responsible for chronic rejection; new techniques have allowed us to identify these antibodies in circulation. The pathogenetic role of the antibodies generally includes the complement pathway, but may also be complement-independent. This paper also examines the pathogenesis of chronic endothelial lesions, as well as the histopathological aspects. Antibodies responsible for chronic rejection may preexist before transplantation or may develop after transplantation. The possible therapeutic approaches are poor and principally based on early identification and desensitisation techniques. New B cell targeting drugs are aimed at an improved control of the relevant condition.

  13. Involvement of miR-338-5p in antibody-mediated renal allograft rejection by targeting TRAF3%微小RNA-338-5p经靶向作用于TRAF3参与肾移植后抗体介导的排斥反应

    Institute of Scientific and Technical Information of China (English)

    徐海燕; 何小舟; 马旭怡; 薛冬; 张雁云; 张学光

    2013-01-01

    Objective To explore the significantly differentially.expressed microRNAs during antibody-mediated renal allograft rejection.Method MicroRNA array assay was used,and the obtained data were analyzed by bioinformatics analysis.The obtained significant microRNAs were further analyzed to forecast the targeted genes in the common database,then experimental means were used to testify the targeted genes.Result During the antibody-mediated renal allograft rejection,the significantly over-expressed microRNAs were miR-200c,miR-200b,miR-30c,miR-30b and miR-30e+,etc.The significantly down-expressed microRNA was miR-338-5p.The bioinformatics analysis results indicated that TRAF3 was the targeted gene of miR-338-5p,which was testified by real time PCR,immunohistochemical assay and fluorescence reporter assay.Conclusion miR-338-5p anticipated in the antibody-mediated renal allograft rejection by targeting TRAF3.%目的 筛选肾移植术后抗体介导排斥反应时有显著差异的微小RNA(miR).方法 采用微小RNA芯片法对移植肾组织进行实验,筛选显著差异微小RNA;对显著差异微小RNA进行生物信息学分析,预测靶基因;对显著差异微小RNA进行实验验证.结果 芯片实验获得显著上调表达的miR-200c、miR-200b、miR-30c、miR-30b、miR-30e+等;显著下调表达的miR-338-5p.生物信息学分析显示肿瘤坏死因子受体作用因子3(TRAF3)为miR-338-5p的靶基因,在后续的荧光定量聚合酶链反应实验、免疫组织化学检测和荧光报告实验中得到证实.结论 miR-338-5p经靶向作用于TRAF3参与肾移植后抗体介导的排斥反应.

  14. Rejected! Cognitions of rejection and intergroup anxiety as mediators of the impact of cross-group friendships on prejudice.

    Science.gov (United States)

    Barlow, Fiona Kate; Louis, Winnifred R; Hewstone, Miles

    2009-09-01

    In a sample of White Australians (N=273), cross-group friendship with Aboriginal Australians was associated with reduced cognitions of rejection and intergroup anxiety, and these variables fully mediated the effect of cross-group friendship on conversational avoidance of sensitive intergroup topics, active avoidance of the outgroup, and old-fashioned prejudice. The novel mediator proposed here, cognitions of rejection, predicted intergroup anxiety, and also predicted the three outcome variables via intergroup anxiety. Over and above its indirect effects via anxiety, cognitions of rejection directly predicted both conversational and active avoidance, suggesting that whilst the cognitive and affective mediators are linked, they predict intergroup outcomes in different ways. The results demonstrate the beneficial impact of cross group friendship in reducing prejudice and avoidance by diminishing cognitions of rejection and intergroup anxiety. We also highlight that individuals without cross-group friends may perceive the outgroup as rejecting, feel anxious about cross-group interaction, and desire both conversational and physical avoidance of the outgroup.

  15. IL-6 Promotes Cardiac Graft Rejection Mediated by CD4+ Cells1

    OpenAIRE

    Booth, Adam Jared; Grabauskiene, Svetlana; Wood, Sherri Chan; Lu, Guanyi; Burrell, Bryna E.; Bishop, D. Keith

    2011-01-01

    IL-6 mediates numerous immunologic effects relevant to transplant rejection; however its specific contributions to these processes are not fully understood. To this end, we neutralized IL-6 in settings of acute cardiac allograft rejection associated with either CD8+ or CD4+ cell dominant responses. In a setting of CD8+ cell dominant graft rejection, IL-6 neutralization delayed the onset of acute rejection while decreasing graft infiltrate and inverting anti-graft Th1/Th2 priming dominance in ...

  16. Cutting edge: membrane lymphotoxin regulates CD8(+) T cell-mediated intestinal allograft rejection.

    Science.gov (United States)

    Guo, Z; Wang, J; Meng, L; Wu, Q; Kim, O; Hart, J; He, G; Zhou, P; Thistlethwaite, J R; Alegre, M L; Fu, Y X; Newell, K A

    2001-11-01

    Blocking the CD28/B7 and/or CD154/CD40 costimulatory pathways promotes long-term allograft survival in many transplant models where CD4(+) T cells are necessary for rejection. When CD8(+) T cells are sufficient to mediate rejection, these approaches fail, resulting in costimulation blockade-resistant rejection. To address this problem we examined the role of lymphotoxin-related molecules in CD8(+) T cell-mediated rejection of murine intestinal allografts. Targeting membrane lymphotoxin by means of a fusion protein, mAb, or genetic mutation inhibited rejection of intestinal allografts by CD8(+) T cells. This effect was associated with decreased monokine induced by IFN-gamma (Mig) and secondary lymphoid chemokine (SLC) gene expression within allografts and spleens respectively. Blocking membrane lymphotoxin did not inhibit rejection mediated by CD4(+) T cells. Combining disruption of membrane lymphotoxin and treatment with CTLA4-Ig inhibited rejection in wild-type mice. These data demonstrate that membrane lymphotoxin is an important regulatory molecule for CD8(+) T cells mediating rejection and suggest a strategy to avoid costimulation blockade-resistant rejection. PMID:11673481

  17. Vector-Mediated In Vivo Antibody Expression.

    Science.gov (United States)

    Schnepp, Bruce C; Johnson, Philip R

    2014-08-01

    This article focuses on a novel vaccine strategy known as vector-mediated antibody gene transfer, with a particular focus on human immunodeficiency virus (HIV). This strategy provides a solution to the problem of current vaccines that fail to generate neutralizing antibodies to prevent HIV-1 infection and AIDS. Antibody gene transfer allows for predetermination of antibody affinity and specificity prior to "immunization" and avoids the need for an active humoral immune response against the HIV envelope protein. This approach uses recombinant adeno-associated viral (rAAV) vectors, which have been shown to transduce muscle with high efficiency and direct the long-term expression of a variety of transgenes, to deliver the gene encoding a broadly neutralizing antibody into the muscle. Following rAAV vector gene delivery, the broadly neutralizing antibodies are endogenously synthesized in myofibers and passively distributed to the circulatory system. This is an improvement over classical passive immunization strategies that administer antibody proteins to the host to provide protection from infection. Vector-mediated gene transfer studies in mice and monkeys with anti-HIV and simian immunodeficiency virus (SIV)-neutralizing antibodies demonstrated long-lasting neutralizing activity in serum with complete protection against intravenous challenge with virulent HIV and SIV. These results indicate that existing potent anti-HIV antibodies can be rapidly moved into the clinic. However, this methodology need not be confined to HIV. The general strategy of vector-mediated antibody gene transfer can be applied to other difficult vaccine targets such as hepatitis C virus, malaria, respiratory syncytial virus, and tuberculosis. PMID:26104192

  18. Role of the spleen in cell-mediated cardiac allograft rejection

    Energy Technology Data Exchange (ETDEWEB)

    Hall, B.M.

    1982-04-01

    A quantitative adoptive transfer assay was used to investigate the role of the spleen in cell-mediated rejection of directly vascularized heart grafts. In this assay, the cell-mediated rejection response can be examined directly by testing the capacity of inocula of T cells to effect rejection of DA heart grafts in PVG rats whose own lymphocytes have been destroyed by whole body irradiation. The capacity of a variety of inocula, including lymph node cells (LNCs), spleen cells, and T cells from lymph node and spleen, to restore rejection were compared in groups of splenectomized and nonsplenectomized hosts. In both groups all inocula restored rejection toward normal. Only in experiments testing inocula equivalent to a small fraction of the naive peripheral lymphocyte pool was rejection delayed in the splenectomized hosts, and this was only a delay of a few days. These results showed that in the absence of the spleen, the primary rejection responses can be generated. In addition, it was demonstrated that the normal spleen contains only a small fraction of the T cell pool with the capacity to effect rejection. Memory T cells were also shown to mediate rejection in splenectomized hosts. It is concluded that with strongly incompatible grafts, splenectomy has only a trivial immunosuppressive effect; it removes neither a sigificant proportion of the alloreactive T cell pool nor the essential site for activation of proliferation of these cells.

  19. Diagnosis and Treatment of Pancreas Rejection

    OpenAIRE

    Redfield, R. R.; Kaufman, D. B.; Odorico, J. S.

    2015-01-01

    Despite significant improvement in pancreas allograft survival, rejection of the pancreas remains a major clinical problem. In addition to cellular rejection of the pancreas, antibody-mediated rejection of the pancreas is now a well-described entity. The 2011 Banff update established comprehensive guidelines for the diagnosis of acute and chronic AMR. The pancreas biopsy is critical in order to accurately diagnose and treat pancreas rejection. Other modes of monitoring pancreas rejection we f...

  20. Gender as predictor of social rejection: the mediating/moderating role of effortful control and parenting

    Directory of Open Access Journals (Sweden)

    Ester Ato

    2014-10-01

    Full Text Available The aim of this work was to analyze the gender differences found in a sample of 474 Spanish children aged between 6 and 8 years with respect to peer rejection using a sociometric status technique. Thus, we analyzed how temperament (Effortful Control and parenting practices (Parental support and Discipline were involved in this relation. To measure social rejection we used the nominations method in the classroom context, while for temperament and parenting practices, parents were given a TMCQ (Temperament in Middle Childhood Questionnaire; Simmonds and Rothbart, 2004 and the Spanish version of the PCRI (Parent-Child Relationship Inventory; Gerard, 1994. Using an statistical modeling approach, we tested various mediation/moderation models until the best one with selected variables was found to explain the relation between these variables. The results confirmed gender differences in social rejection, with boys being rejected more than girls. The model that gave the best fit was the one that placed effortful control latent variable mediating the relation between gender and social rejection and parenting practices as a latent explanatory variable of effortful control. In conclusion, differences between girls and boys in social rejection are to a large extent explained by the significantly lower scores for boys in effortful control construct and, in turn, these lowest scores are explained by negative parental practices, with low levels of support and discipline.

  1. Antibody-Mediated Autoimmune Encephalopathies and Immunotherapies.

    Science.gov (United States)

    Gastaldi, Matteo; Thouin, Anaïs; Vincent, Angela

    2016-01-01

    Over the last 15 years it has become clear that rare but highly recognizable diseases of the central nervous system (CNS), including newly identified forms of limbic encephalitis and other encephalopathies, are likely to be mediated by antibodies (Abs) to CNS proteins. The Abs are directed against membrane receptors and ion channel-associated proteins that are expressed on the surface of neurons in the CNS, such as N-methyl D-aspartate receptors and leucine-rich, glioma inactivated 1 protein and contactin-associated protein like 2, that are associated with voltage-gated potassium channels. The diseases are not invariably cancer-related and are therefore different from the classical paraneoplastic neurological diseases that are associated with, but not caused by, Abs to intracellular proteins. Most importantly, the new antibody-associated diseases almost invariably respond to immunotherapies with considerable and sometimes complete recovery, and there is convincing evidence of their pathogenicity in the relatively limited studies performed so far. Treatments include first-line steroids, intravenous immunoglobulins, and plasma exchange, and second-line rituximab and cyclophosphamide, followed in many cases by steroid-sparing agents in the long-term. This review focuses mainly on N-methyl D-aspartate receptor- and voltage-gated potassium channel complex-related Abs in adults, the clinical phenotypes, and treatment responses. Pediatric cases are referred to but not reviewed in detail. As there have been very few prospective studies, the conclusions regarding immunotherapies are based on retrospective studies. PMID:26692392

  2. Antibody-Mediated Internalization of Infectious HIV-1 Virions Differs among Antibody Isotypes and Subclasses.

    Science.gov (United States)

    Tay, Matthew Zirui; Liu, Pinghuang; Williams, LaTonya D; McRaven, Michael D; Sawant, Sheetal; Gurley, Thaddeus C; Xu, Thomas T; Dennison, S Moses; Liao, Hua-Xin; Chenine, Agnès-Laurence; Alam, S Munir; Moody, M Anthony; Hope, Thomas J; Haynes, Barton F; Tomaras, Georgia D

    2016-08-01

    Emerging data support a role for antibody Fc-mediated antiviral activity in vaccine efficacy and in the control of HIV-1 replication by broadly neutralizing antibodies. Antibody-mediated virus internalization is an Fc-mediated function that may act at the portal of entry whereby effector cells may be triggered by pre-existing antibodies to prevent HIV-1 acquisition. Understanding the capacity of HIV-1 antibodies in mediating internalization of HIV-1 virions by primary monocytes is critical to understanding their full antiviral potency. Antibody isotypes/subclasses differ in functional profile, with consequences for their antiviral activity. For instance, in the RV144 vaccine trial that achieved partial efficacy, Env IgA correlated with increased risk of HIV-1 infection (i.e. decreased vaccine efficacy), whereas V1-V2 IgG3 correlated with decreased risk of HIV-1 infection (i.e. increased vaccine efficacy). Thus, understanding the different functional attributes of HIV-1 specific IgG1, IgG3 and IgA antibodies will help define the mechanisms of immune protection. Here, we utilized an in vitro flow cytometric method utilizing primary monocytes as phagocytes and infectious HIV-1 virions as targets to determine the capacity of Env IgA (IgA1, IgA2), IgG1 and IgG3 antibodies to mediate HIV-1 infectious virion internalization. Importantly, both broadly neutralizing antibodies (i.e. PG9, 2G12, CH31, VRC01 IgG) and non-broadly neutralizing antibodies (i.e. 7B2 mAb, mucosal HIV-1+ IgG) mediated internalization of HIV-1 virions. Furthermore, we found that Env IgG3 of multiple specificities (i.e. CD4bs, V1-V2 and gp41) mediated increased infectious virion internalization over Env IgG1 of the same specificity, while Env IgA mediated decreased infectious virion internalization compared to IgG1. These data demonstrate that antibody-mediated internalization of HIV-1 virions depends on antibody specificity and isotype. Evaluation of the phagocytic potency of vaccine

  3. Preformed class II donor-specific antibodies are associated with an increased risk of early rejection after liver transplantation.

    Science.gov (United States)

    O'Leary, Jacqueline G; Kaneku, Hugo; Jennings, Linda W; Bañuelos, Nubia; Susskind, Brian M; Terasaki, Paul I; Klintmalm, Göran B

    2013-09-01

    Preformed donor-specific human leukocyte antigen antibodies (DSAs) are considered a contraindication to the transplantation of most solid organs other than the liver. Conflicting data currently exist on the importance of preformed DSAs in rejection and patient survival after liver transplantation (LT). To evaluate preformed DSAs in LT, we retrospectively analyzed prospectively collected samples from all adult recipients of primary LT without another organ from January 1, 2000 to May 31, 2009 with a pre-LT sample available (95.8% of the patients). Fourteen percent of the patients had preformed class I and/or II DSAs with a mean fluorescence intensity (MFI) ≥ 5000. Preformed class I DSAs with an MFI ≥ 5000 remained persistent in only 5% of patients and were not associated with rejection. Preformed class II DSAs with an MFI of 5000 to 10,000 remained persistent in 23% of patients, and this rate increased to 33% for patients whose MFI was ≥10,000 (P rejection [hazard ratio (HR) = 1.58; p = 0.004]. In addition, multivariate modeling showed that in comparison with no DSAs (MFI < 1000), preformed class I and/or II DSAs with an MFI ≥ 5000 were independently correlated with the risk of death (HR = 1.51; p = 0.02).

  4. Detection of C3d-Binding Donor-Specific Anti-HLA Antibodies at Diagnosis of Humoral Rejection Predicts Renal Graft Loss

    Science.gov (United States)

    Sicard, Antoine; Ducreux, Stéphanie; Rabeyrin, Maud; Couzi, Lionel; McGregor, Brigitte; Badet, Lionel; Scoazec, Jean Yves; Bachelet, Thomas; Lepreux, Sébastien; Visentin, Jonathan; Merville, Pierre; Fremeaux-Bacchi, Véronique; Morelon, Emmanuel; Taupin, Jean-Luc; Dubois, Valérie

    2015-01-01

    Antibody-mediated rejection (AMR) is a major cause of kidney graft loss, yet assessment of individual risk at diagnosis is impeded by the lack of a reliable prognosis assay. Here, we tested whether the capacity of anti-HLA antibodies to bind complement components allows accurate risk stratification at the time of AMR diagnosis. Among 938 kidney transplant recipients for whom a graft biopsy was performed between 2004 and 2012 at the Lyon University Hospitals, 69 fulfilled the diagnosis criteria for AMR and were enrolled. Sera banked at the time of the biopsy were screened for the presence of donor-specific anti-HLA antibodies (DSAs) and their ability to bind C1q and C3d using flow bead assays. In contrast with C4d graft deposition, the presence of C3d-binding DSA was associated with a higher risk of graft loss (P<0.001). Despite similar trend, the difference did not reach significance with a C1q-binding assay (P=0.06). The prognostic value of a C3d-binding assay was further confirmed in an independent cohort of 39 patients with AMR (P=0.04). Patients with C3d-binding antibodies had worse eGFR and higher DSA mean fluorescence intensity. In a multivariate analysis, only eGFR<30 ml/min per 1.73 m2 (hazard ratio [HR], 3.56; 95% confidence interval [CI], 1.46 to 8.70; P=0.005) and the presence of circulating C3d-binding DSA (HR, 2.80; 95% CI, 1.12 to 6.95; P=0.03) were independent predictors for allograft loss at AMR diagnosis. We conclude that assessment of the C3d-binding capacity of DSA at the time of AMR diagnosis allows for identification of patients at risk for allograft loss. PMID:25125383

  5. ICOS Promotes the Function of CD4+ Effector T Cells during Anti-OX40-Mediated Tumor Rejection.

    Science.gov (United States)

    Metzger, Todd C; Long, Hua; Potluri, Shobha; Pertel, Thomas; Bailey-Bucktrout, Samantha L; Lin, John C; Fu, Tihui; Sharma, Padmanee; Allison, James P; Feldman, Reid M R

    2016-07-01

    ICOS is a T-cell coregulatory receptor that provides a costimulatory signal to T cells during antigen-mediated activation. Antitumor immunity can be improved by ICOS-targeting therapies, but their mechanism of action remains unclear. Here, we define the role of ICOS signaling in antitumor immunity using a blocking, nondepleting antibody against ICOS ligand (ICOS-L). ICOS signaling provided critical support for the effector function of CD4(+) Foxp3(-) T cells during anti-OX40-driven tumor immune responses. By itself, ICOS-L blockade reduced accumulation of intratumoral T regulatory cells (Treg), but it was insufficient to substantially inhibit tumor growth. Furthermore, it did not impede antitumor responses mediated by anti-4-1BB-driven CD8(+) T cells. We found that anti-OX40 efficacy, which is based on Treg depletion and to a large degree on CD4(+) effector T cell (Teff) responses, was impaired with ICOS-L blockade. In contrast, the provision of additional ICOS signaling through direct ICOS-L expression by tumor cells enhanced tumor rejection and survival when administered along with anti-OX40 therapy. Taken together, our results showed that ICOS signaling during antitumor responses acts on both Teff and Treg cells, which have opposing roles in promoting immune activation. Thus, effective therapies targeting the ICOS pathway should seek to promote ICOS signaling specifically in effector CD4(+) T cells by combining ICOS agonism and Treg depletion. Cancer Res; 76(13); 3684-9. ©2016 AACR. PMID:27197182

  6. Antibody-mediated Prevention of Fusarium Mycotoxins in the Field

    OpenAIRE

    Yu-Cai Liao; Elena Glinka; Jing-Bo Zhang; He-Ping Li; Zu-Quan Hu

    2008-01-01

    Fusarium mycotoxins directly accumulated in grains during the infection of wheat and other cereal crops by Fusarium head blight (FHB) pathogens are detrimental to humans and domesticated animals. Prevention of the mycotoxins via the development of FHB-resistant varieties has been a challenge due to the scarcity of natural resistance against FHB pathogens. Various antibodies specific to Fusarium fungi and mycotoxins are widely used in immunoassays and antibody-mediated resistance in planta aga...

  7. Association between the presence of anti-HLA antibodies with acute rejection and chronic allograft nephropathy in the first year after kidney transplantation.

    Science.gov (United States)

    Toresan, R; Manfro, R C; Proença, M C C; Veronese, F J V; Salim, P H; da Silva, D M; Ribeiro, A R; Edelweiss, M I A; Pegas, K L; Jobim, L F J

    2008-04-01

    The clinical relevance of anti-HLA antibodies following kidney transplantation has been a recent focus of research. Patients who present anti-HLA antibodies in the posttransplantation period have shown higher incidences of acute rejection episodes (ARE) and chronic allograft nephropathy (CAN). The objective of this study was to evaluate the presence of anti-HLA antibodies during the first year after kidney transplantation and their association with the occurrence of ARE and CAN. Eighty-eight kidney transplant recipients were evaluated for the presence of IgG anti-HLA antibodies using an enzyme-linked immunosorbent assay (LAT-M and LAT-1240, One Lambda Inc, Calif, United States). Protocol kidney biopsies were performed in consenting patients. ARE and CAN were diagnosed by clinical, laboratory, and histopathological criteria. Anti-HLA antibodies were observed in 20 (22.7%) patients. At 1 year follow-up, 26.1% presented ARE and 51.2% developed CAN. Nine patients (45%) with antibodies developed ARE as opposed to 20.6% without antibodies and 64.7% developed CAN as opposed to 47.8% of those without antibodies. In the histological analysis, the anti-HLA antibodies were associated with Banff IIA ARE (P = .001) and Banff grade II CAN (P = .012). Routine posttransplantation search for antibodies may identify cases at higher risk for acute and chronic rejection, and perhaps help to tailor the immunosuppressive regimen. PMID:18454996

  8. Multifactorial aspects of antibody-mediated blood cell destruction

    NARCIS (Netherlands)

    R. Kapur

    2014-01-01

    The research described in this thesis focuses on diseases of antibody-mediated blood cell destruction via FcγRs on phagocytes, in particular regarding platelets in fetal or neonatal alloimmune thrombocytopenia (FNAIT) and red blood cells (RBC) in hemolytic disease of the fetus and newborn (HDFN). Di

  9. MicroRNA-10b downregulation mediates acute rejection of renal allografts by derepressing BCL2L11

    International Nuclear Information System (INIS)

    Kidney transplantation is the major therapeutic option for end-stage kidney diseases. However, acute rejection could cause allograft loss in some of these patients. Emerging evidence supports that microRNA (miRNA) dysregulation is implicated in acute allograft rejection. In this study, we used next-generation sequencing to profile miRNA expression in normal and acutely rejected kidney allografts. Among 75 identified dysregulated miRNAs, miR-10b was the most significantly downregulated miRNAs in rejected allografts. Transfecting miR-10b inhibitor into human renal glomerular endothelial cells recapitulated key features of acute allograft rejection, including endothelial cell apoptosis, release of pro-inflammatory cytokines (interleukin-6, tumor necrosis factor α, interferon-γ, and chemokine (C–C motif) ligand 2) and chemotaxis of macrophages whereas transfection of miR-10b mimics had opposite effects. Downregulation of miR-10b directly derepressed the expression of BCL2L11 (an apoptosis inducer) as revealed by luciferase reporter assay. Taken together, miR-10b downregulation mediates many aspects of disease pathogenicity of acute kidney allograft rejection. Restoring miR-10b expression in glomerular endothelial cells could be a novel therapeutic approach to reduce acute renal allograft loss. - Highlights: • miR-10b was the most downregulated microRNAs in acutely rejected renal allografts. • miR-10b downregulation triggered glomerular endothelial cell apoptosis. • miR-10b downregulation induced release of pro-inflammatory cytokines. • miR-10b downregulation derepressed its pro-apoptotic target BCL2L11

  10. MicroRNA-10b downregulation mediates acute rejection of renal allografts by derepressing BCL2L11

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiaoyou [Department of Organ Transplantation, Zhujiang Hospital, Guangzhou 510282 (China); Dong, Changgui [Institute of Molecular Ecology and Evolution, East China Normal University, Shanghai 200062 (China); Jiang, Zhengyao [Department of Organ Transplantation, Zhujiang Hospital, Guangzhou 510282 (China); Wu, William K.K. [Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong, Shatin, NT, Hong Kong (China); State Key Laboratory of Digestive Diseases, LKS Institute of Health Sciences, The Chinese University of Hong Kong, Shatin, NT, Hong Kong (China); Chan, Matthew T.V. [Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong, Shatin, NT, Hong Kong (China); Zhang, Jie [Department of Organ Transplantation, Zhujiang Hospital, Guangzhou 510282 (China); Li, Haibin; Qin, Ke [Guangxi Key Laboratory for Transplantation Medicine Department of Organ Transplantation in Guangzhou Military Region, Institute of Transplant Medicine, 303 Hospital of People' s Liberation Army, Nanning, Guangxi 530021 (China); Sun, Xuyong, E-mail: sunxuyong0528@163.com [Guangxi Key Laboratory for Transplantation Medicine Department of Organ Transplantation in Guangzhou Military Region, Institute of Transplant Medicine, 303 Hospital of People' s Liberation Army, Nanning, Guangxi 530021 (China)

    2015-04-10

    Kidney transplantation is the major therapeutic option for end-stage kidney diseases. However, acute rejection could cause allograft loss in some of these patients. Emerging evidence supports that microRNA (miRNA) dysregulation is implicated in acute allograft rejection. In this study, we used next-generation sequencing to profile miRNA expression in normal and acutely rejected kidney allografts. Among 75 identified dysregulated miRNAs, miR-10b was the most significantly downregulated miRNAs in rejected allografts. Transfecting miR-10b inhibitor into human renal glomerular endothelial cells recapitulated key features of acute allograft rejection, including endothelial cell apoptosis, release of pro-inflammatory cytokines (interleukin-6, tumor necrosis factor α, interferon-γ, and chemokine (C–C motif) ligand 2) and chemotaxis of macrophages whereas transfection of miR-10b mimics had opposite effects. Downregulation of miR-10b directly derepressed the expression of BCL2L11 (an apoptosis inducer) as revealed by luciferase reporter assay. Taken together, miR-10b downregulation mediates many aspects of disease pathogenicity of acute kidney allograft rejection. Restoring miR-10b expression in glomerular endothelial cells could be a novel therapeutic approach to reduce acute renal allograft loss. - Highlights: • miR-10b was the most downregulated microRNAs in acutely rejected renal allografts. • miR-10b downregulation triggered glomerular endothelial cell apoptosis. • miR-10b downregulation induced release of pro-inflammatory cytokines. • miR-10b downregulation derepressed its pro-apoptotic target BCL2L11.

  11. A laboratory-based examination of responses to social rejection in borderline personality disorder: the mediating role of emotion dysregulation.

    Science.gov (United States)

    Dixon-Gordon, Katherine L; Gratz, Kim L; Breetz, Alisa; Tull, Matthew

    2013-04-01

    This study sought to build upon existing research on interpersonal sensitivity in borderline personality disorder (BPD) by examining whether emotion dysregulation mediates the relationship between BPD and cognitive and emotional responses to social rejection. Participants with (n = 53) and without (n = 34) BPD reported on levels of negative affect and threat to four social needs (perceived control, belonging, selfesteem, and meaningful existence) in response to a laboratory-based social ostracism task (Cyberball). Results revealed heightened interpersonal (rejection) sensitivity among BPD (vs. non-BPD) participants, as evidenced by heightened threat to all social needs and nonspecific distress (although not overall negative affect) in response to the task. Furthermore, both overall emotion dysregulation and the specific dimensions involving emotion modulation strategies, emotional clarity, and the control of behaviors when distressed mediated the relationship between BPD status and several cognitive (threats to meaningful existence, belonging, and self-esteem) and emotional (nonspecific distress) responses to the task. PMID:23514181

  12. Multifactorial aspects of antibody-mediated blood cell destruction

    OpenAIRE

    Schoot, van der, B.H.; Vidarsson, G.; Kapur, R.

    2014-01-01

    The research described in this thesis focuses on diseases of antibody-mediated blood cell destruction via FcγRs on phagocytes, in particular regarding platelets in fetal or neonatal alloimmune thrombocytopenia (FNAIT) and red blood cells (RBC) in hemolytic disease of the fetus and newborn (HDFN). Diagnostically, for HDFN laboratory tests are in place in order to predict risk for severe fetal RBC destruction and thereby initiate appropriate treatments. This test is sensitive, but has relativel...

  13. T10B9 monoclonal antibody: A short-acting nonstimulating monoclonal antibody that spares γδ T-cells and treats and prevents cellular rejection

    Directory of Open Access Journals (Sweden)

    Thomas H Waid

    2009-06-01

    Full Text Available Thomas H Waid1, John S Thompson1, Maria Siemionow2, Stephen A Brown1 1Department of Internal Medicine, University of Kentucky, Lexington, Kentucky, USA; 2Cleveland Clinic, Cleveland, Ohio, USAAbstract: T10B9.1A-31/MEDI-500 is a nonmitogenic immunoglobulin M kappa murine monoclonal antibody (mAb directed against the alpha-beta (αβ heterodimer of the T-lymphocyte receptor complex. The hybridoma was first produced by fusing spleen cells from BALB/C mice immunized with human peripheral blood T-lymphocytes with SP2/O-Ag14 mutant myeloma cells. The mAb is produced and purified using multistep ion exchange and molecular sieve chromatography protocols. T10B9 has been used successfully to treat acute cellular rejection in renal transplantation and as an immunosuppression induction agent in heart and simultaneous kidney-pancreas transplantation. Because T10B9 is nonmitogenic and causes minimal cytokine release, both treatment of rejection and induction of immunosuppression were accomplished with significantly fewer and milder untoward effects (cytokine release syndrome than its comparator OKT3. Since T10B9 is directed against the αβ heterodimer of the CD3 epitope, it spares the gamma delta (γδ region. These gamma delta (γδ T cells have a unique role in the immune response controlling many serious human diseases and perhaps facilitating the development of immunologic tolerance. T10B9 has a relatively short duration of action, depleting T cells for only 10 to 14 days, unlike the protracted depletion seen with thymoglobulin and Campath-1H. There is no B-lymphocyte depletion with T10B9 as there is with both of the aforementioned reagents. The lack of prolonged lymphocyte depletion may account for less infection observed with T10B9 treatment.Keywords: T10B9.1A-31, γδ T-cell, monoclonal antibody, Campath-1H, thymoglobulin, OKT3

  14. Novel antimalarial antibodies highlight the importance of the antibody Fc region in mediating protection.

    Science.gov (United States)

    Pleass, Richard J; Ogun, Solabomi A; McGuinness, David H; van de Winkel, Jan G J; Holder, Anthony A; Woof, Jenny M

    2003-12-15

    Parasite drug resistance and difficulties in developing effective vaccines have precipitated the search for alternative therapies for malaria. The success of passive immunization suggests that immunoglobulin (Ig)-based therapies are effective. To further explore the mechanism(s) by which antibody mediates its protective effect, we generated human chimeric IgG1 and IgA1 and a single-chain diabody specific for the C-terminal 19-kDa region of Plasmodium yoelii merozoite surface protein 1 (MSP119), a major target of protective immune responses. These novel human reagents triggered in vitro phagocytosis of merozoites but, unlike their parental mouse IgG2b, failed to protect against parasite challenge in vivo. Therefore, the Fc region appears critical for mediating protection in vivo, at least for this MSP119 epitope. Such antibodies may serve as prototype therapeutic agents, and as useful tools in the development of in vitro neutralization assays with Plasmodium parasites. PMID:12855589

  15. Depression of Complement Regulatory Factors in Rat and Human Renal Grafts Is Associated with the Progress of Acute T-Cell Mediated Rejection.

    Directory of Open Access Journals (Sweden)

    Kazuaki Yamanaka

    Full Text Available The association of complement with the progression of acute T cell mediated rejection (ATCMR is not well understood. We investigated the production of complement components and the expression of complement regulatory proteins (Cregs in acute T-cell mediated rejection using rat and human renal allografts.We prepared rat allograft and syngeneic graft models of renal transplantation. The expression of Complement components and Cregs was assessed in the rat grafts using quantitative real-time PCR (qRT-PCR and immunofluorescent staining. We also administered anti-Crry and anti-CD59 antibodies to the rat allograft model. Further, we assessed the relationship between the expression of membrane cofactor protein (MCP by immunohistochemical staining in human renal grafts and their clinical course.qRT-PCR results showed that the expression of Cregs, CD59 and rodent-specific complement regulator complement receptor 1-related gene/protein-y (Crry, was diminished in the rat allograft model especially on day 5 after transplantation in comparison with the syngeneic model. In contrast, the expression of complement components and receptors: C3, C3a receptor, C5a receptor, Factor B, C9, C1q, was increased, but not the expression of C4 and C5, indicating a possible activation of the alternative pathway. When anti-Crry and anti-CD59 mAbs were administered to the allograft, the survival period for each group was shortened. In the human ATCMR cases, the group with higher MCP expression in the grafts showed improved serum creatinine levels after the ATCMR treatment as well as a better 5-year graft survival rate.We conclude that the expression of Cregs in allografts is connected with ATCMR. Our results suggest that controlling complement activation in renal grafts can be a new strategy for the treatment of ATCMR.

  16. An Essential Role for Tumor Necrosis Factor in Natural Killer Cell–mediated Tumor Rejection in the Peritoneum

    OpenAIRE

    Smyth, Mark J.; Kelly, Janice M.; Baxter, Alan G.; Körner, Heinrich; Sedgwick, Jonathon D.

    1998-01-01

    Natural killer (NK) cells are thought to provide the first line of defence against tumors, particularly major histocompatibility complex (MHC) class I− variants. We have confirmed in C57BL/6 (B6) mice lacking perforin that peritoneal growth of MHC class I− RMA-S tumor cells in unprimed mice is controlled by perforin-dependent cytotoxicity mediated by CD3− NK1.1+ cells. Furthermore, we demonstrate that B6 mice lacking tumor necrosis factor (TNF) are also significantly defective in their reject...

  17. A Neutralizing Antibody Assay Based on a Reporter of Antibody-Dependent Cell-Mediated Cytotoxicity.

    Science.gov (United States)

    Wu, Yuling; Li, Jia J; Kim, Hyun Jun; Liu, Xu; Liu, Weiyi; Akhgar, Ahmad; Bowen, Michael A; Spitz, Susan; Jiang, Xu-Rong; Roskos, Lorin K; White, Wendy I

    2015-11-01

    Benralizumab is a humanized anti-IL5 receptor α (IL5Rα) monoclonal antibody (mAb) with enhanced (afucosylation) antibody-dependent cell-mediated cytotoxicity (ADCC) function. An ADCC reporter cell-based neutralizing antibody (NAb) assay was developed and characterized to detect NAb against benralizumab in human serum to support the clinical development of benralizumab. The optimal ratio of target cells to effector cells was 3:1. Neither parental benralizumab (fucosylated) nor benralizumab Fab resulted in ADCC activity, confirming the requirement for ADCC activity in the NAb assay. The serum tolerance of the cells was determined to be 2.5%. The cut point derived from normal and asthma serum samples was comparable. The effective range of benralizumab was determined, and 35 ng/mL [80% maximal effective concentration (EC80)] was chosen as the standard concentration to run in the assessment of NAb. An affinity purified goat anti-benralizumab polyclonal idiotype antibody preparation was shown to have NAb since it inhibited ADCC activity in a dose-dependent fashion. The low endogenous concentrations of IL5 and soluble IL5 receptor (sIL5R) did not demonstrate to interfere with the assay. The estimated assay sensitivities at the cut point were 1.02 and 1.10 μg/mL as determined by the surrogate neutralizing goat polyclonal and mouse monoclonal anti-drug antibody (ADA) controls, respectively. The assay can detect NAb (at 2.5 μg/mL) in the presence of 0.78 μg/mL benralizumab. The assay was not susceptible to non-specific matrix effects. This study provides an approach and feasibility of developing an ADCC cell-based NAb assay to support biopharmaceuticals with an ADCC function. PMID:26205082

  18. Lipid raft facilitated ligation of K-{alpha}1-tubulin by specific antibodies on epithelial cells: Role in pathogenesis of chronic rejection following human lung transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Tiriveedhi, Venkataswarup; Angaswamy, Nataraju [Department of Surgery, Pathology and Immunology, Washington University School of Medicine, St. Louis, MO (United States); Weber, Joseph [Department of Medicine, Washington University School of Medicine, St. Louis, MO (United States); Mohanakumar, T., E-mail: kumart@wustl.edu [Department of Surgery, Pathology and Immunology, Washington University School of Medicine, St. Louis, MO (United States)

    2010-08-20

    Research highlights: {yields} Addition of KAT Abs (+) sera to NHBE culture causes upregulation of growth factors. {yields} Cholesterol depletion causes down regulation of growth factor expression. {yields} Cholesterol depletion is accompanied by loss of membrane bound caveolin. {yields} Thus, we demonstrate lipid raft are critical for efficient ligation of the KAT Abs. -- Abstract: Long term function of human lung allografts is hindered by development of chronic rejection manifested as Bronchiolitis Obliterans Syndrome (BOS). We have previously identified the development of antibodies (Abs) following lung transplantation to K-{alpha}1-tubulin (KAT), an epithelial surface gap junction cytoskeletal protein, in patients who develop BOS. However, the biochemical and molecular basis of the interactions and signaling cascades mediated by KAT Abs are yet to be defined. In this report, we investigated the biophysical basis of the epithelial cell membrane surface interaction between KAT and its specific Abs. Towards this, we analyzed the role of the lipid raft-domains in the membrane interactions which lead to cell signaling and ultimately increased growth factor expression. Normal human bronchial epithelial (NHBE) cells, upon specific ligation with Abs to KAT obtained either from the serum of BOS(+) patients or monoclonal KAT Abs, resulted in upregulation of growth factors VEGF, PDGF, and bFGF (6.4 {+-} 1.1-, 3.2 {+-} 0.9-, and 3.4 {+-} 1.1-fold increase, respectively) all of which are important in the pathogenesis of BOS. To define the role for lipid raft in augmenting surface interactions, we analyzed the changes in the growth factor expression pattern upon depletion and enrichment with lipid raft following the ligation of the epithelial cell membranes with Abs specific for KAT. NHBE cells cultured in the presence of {beta}-methyl cyclodextran ({beta}MCD) had significantly reduced growth factor expression (1.3 {+-} 0.3, vs {beta}MCD untreated being 6.4 {+-} 1.1-fold

  19. Arsenic trioxide inhibits accelerated allograft rejection mediated by alloreactive CD8(+) memory T cells and prolongs allograft survival time.

    Science.gov (United States)

    Li, Chun; Guan, Tianjun; Gao, Chang; Lin, Yingying; Yan, Guoliang; Zhu, Maoshu; Lv, Chongshan; Xia, Junjie; Qi, Zhongquan

    2015-09-01

    CD8(+) memory T (Tm) cells are a significant barrier to transplant tolerance induction in alloantigen-primed recipients, and are insensitive to existing clinical immunosuppressants. Here, we studied the inhibition of CD8(+) Tm cells by arsenic trioxide (As2O3) for the first time. Alloantigen-primed CD8(+) Tm cells were transferred to T cell immunodeficient nude mice. The mice were subjected to heart allotransplantation, and treated with As2O3. The transplant survival time was determined, and the inhibitory effects of As2O3 on CD8(+) Tm cell-mediated immune rejection were assessed through serological studies and inspection of the transplanted heart and lymphoid organs. We found that As2O3 treatment prolonged the mean survival time of the graft and reduced the number of CD8(+) Tm cells in the spleen and lymph nodes. The expression of the genes encoding interleukin (IL)-2, and IFN-γ was reduced, while expression of IL-10 and transforming growth factor-β was increased in the transplant. Our findings show that As2O3 treatment inhibits allograft rejection mediated by alloreactive CD8(+) Tm cells in the mouse heart transplantation model.

  20. The Natural History of Biopsy-Negative Rejection after Heart Transplantation

    OpenAIRE

    Zhaoyi Tang; Jon Kobashigawa; Matthew Rafiei; Lily Kagan Stern; Michele Hamilton

    2013-01-01

    Purpose. The most recent International Society for Heart and Lung Transplantation (ISHLT) biopsy scale classifies cellular and antibody-mediated rejections. However, there are cases with acute decline in left ventricular ejection fraction (LVEF ≤ 45%) but no evidence of rejection on biopsy. Characteristics and treatment response of this biopsy negative rejection (BNR) have yet to be elucidated. Methods. Between 2002 and 2012, we found 12 cases of BNR in 11 heart transplant patients as previou...

  1. Antibody-mediated neutralization of African swine fever virus: myths and facts.

    Science.gov (United States)

    Escribano, José M; Galindo, Inmaculada; Alonso, Covadonga

    2013-04-01

    Almost all viruses can be neutralized by antibodies. However, there is some controversy about antibody-mediated neutralization of African swine fever virus (ASFV) with sera from convalescent pigs and about the protective relevance of antibodies in experimentally vaccinated pigs. At present, there is no vaccine available for this highly lethal and economically relevant virus and all classical attempts to generate a vaccine have been unsuccessful. This failure has been attributed, in part, to what many authors describe as the absence of neutralizing antibodies. The findings of some studies clearly contradict the paradigm of the impossibility to neutralize ASFV by means of monoclonal or polyclonal antibodies. This review discusses scientific evidence of these types of antibodies in convalescent and experimentally immunized animals, the nature of their specificity, the neutralization-mediated mechanisms demonstrated, and the potential relevance of antibodies in protection. PMID:23159730

  2. JC polyomavirus mutants escape antibody-mediated neutralization.

    Science.gov (United States)

    Ray, Upasana; Cinque, Paola; Gerevini, Simonetta; Longo, Valeria; Lazzarin, Adriano; Schippling, Sven; Martin, Roland; Buck, Christopher B; Pastrana, Diana V

    2015-09-23

    JC polyomavirus (JCV) persistently infects the urinary tract of most adults. Under conditions of immune impairment, JCV causes an opportunistic brain disease, progressive multifocal leukoencephalopathy (PML). JCV strains found in the cerebrospinal fluid of PML patients contain distinctive mutations in surface loops of the major capsid protein, VP1. We hypothesized that VP1 mutations might allow the virus to evade antibody-mediated neutralization. Consistent with this hypothesis, neutralization serology revealed that plasma samples from PML patients neutralized wild-type JCV strains but failed to neutralize patient-cognate PML-mutant JCV strains. This contrasted with serological results for healthy individuals, most of whom robustly cross-neutralized all tested JCV variants. Mice administered a JCV virus-like particle (VLP) vaccine initially showed neutralizing "blind spots" (akin to those observed in PML patients) that closed after booster immunization. A PML patient administered an experimental JCV VLP vaccine likewise showed markedly increased neutralizing titer against her cognate PML-mutant JCV. The results indicate that deficient humoral immunity is a common aspect of PML pathogenesis and that vaccination may overcome this humoral deficiency. Thus, vaccination with JCV VLPs might prevent the development of PML.

  3. Social rejection following neonatal inflammation is mediated by olfactory scent cues.

    Science.gov (United States)

    MacRae, M; Kenkel, W M; Kentner, A C

    2015-10-01

    Early-life exposure to inflammation has been associated with several behavioral and cognitive deficits detected in adulthood. However, early behavioral changes have not been well described in rodent models of infection, specifically with respect to social behavior. In the present work we show that lipopolysaccharide (LPS) challenge at 3 and 5days of age reduced overall social contact time in male juvenile rats, primarily mediated by the amount of contact they received from a novel conspecific. Given that there are important sensory, motor, and motivational components that underlie social interaction we sought to uncover the mechanism(s) responsible for the reduced social contact directed towards neonatal (n)LPS treated animals. Using an intranasal perfusion procedure, we induced a ZnSO4 lesion in a subset of novel conspecifics, effectively disrupting their olfactory processing via olfactory neuroepithelium degeneration. Overall, this procedure equalized the amount of social contact directed towards nLPS animals compared to nsaline rats. To determine whether nLPS disrupted auditory communication we evaluated ultrasonic vocalizations (USVs) for the total number and duration of calls, and the average duration and frequency from each vocalization recording. There were no differences in USVs across treatment groups. Treating nLPS rats with diazepam maintained the level of social contact they initiated, compared to the stress-induced decrease observed in their saline treated counterparts. However, diazepam did not stabilize the amount of contact directed towards them. Together, this indicates that neither vocalized motor pathways nor anxiety cues, mediated by auditory/motor communication, are involved in the social deficits following nLPS. Instead, our data suggest that olfactory indicators, likely mediated through microbiota/immunomodulatory scent signals underlie the reductions in social contact that follow neonatal inflammation.

  4. Mechanism of human antibody-mediated neutralization of Marburg virus.

    Science.gov (United States)

    Flyak, Andrew I; Ilinykh, Philipp A; Murin, Charles D; Garron, Tania; Shen, Xiaoli; Fusco, Marnie L; Hashiguchi, Takao; Bornholdt, Zachary A; Slaughter, James C; Sapparapu, Gopal; Klages, Curtis; Ksiazek, Thomas G; Ward, Andrew B; Saphire, Erica Ollmann; Bukreyev, Alexander; Crowe, James E

    2015-02-26

    The mechanisms by which neutralizing antibodies inhibit Marburg virus (MARV) are not known. We isolated a panel of neutralizing antibodies from a human MARV survivor that bind to MARV glycoprotein (GP) and compete for binding to a single major antigenic site. Remarkably, several of the antibodies also bind to Ebola virus (EBOV) GP. Single-particle EM structures of antibody-GP complexes reveal that all of the neutralizing antibodies bind to MARV GP at or near the predicted region of the receptor-binding site. The presence of the glycan cap or mucin-like domain blocks binding of neutralizing antibodies to EBOV GP, but not to MARV GP. The data suggest that MARV-neutralizing antibodies inhibit virus by binding to infectious virions at the exposed MARV receptor-binding site, revealing a mechanism of filovirus inhibition. PMID:25723164

  5. Trypanosoma cruzi: antigen-receptor mediated endocytosis of antibody

    Directory of Open Access Journals (Sweden)

    Judith Abelha

    1981-06-01

    Full Text Available Trypanomastigote forms of Trypanosoma cruzi were derived from tissue culture and incubated with immune and non-immune human sera. All immune sera showed high titers of specific humoral antibodies of the IgM or the IgG type. Agglutination and swelling of parasites were observed after incubation at 37ºC, but many trypomastigotes remained free-swimming in the sera for two to three days. The quantitiy of immune serum capable of lysing a maximum of 10 x 10 [raised to the power of 6] sensitized red cells was not capable of lysing 4 x 10 [raised to the power of 3] tripomastigotes. Typically, the parasites underwent cyclical changes with the formation of clumps of amastigotes and the appearance of epimastigote forms. Multiplication of the parasites was observed in immune sera. Further, the infectivity of the parasites to susceptible mice was not lost. All sera used produced similar general effects on the growth of the parasite. The antibody bound to T. cruzi appeard to enter cells by antigen-receptor mediated endocytosis. The ferritin-conjugated antibody was internalized and delivered to phagolysosomes where they might be completely degraded to amino-acids. This seemed to be a coupled process by which the immunoglobulin is first bound to specific parasite surface receptor and then rapidly endocytosed by the cell.Formas tripomastigotas de Trypanosoma cruzi derivadas de cultura de tecido foram encubadas com soros humanos imunes e não-imunes.Todos os soros humanos usados tinham títulos elevados de anticorpos das classes IgM ou IgG. Aglutinação e entumescimento dos parasitos eram observados apos encubação a 37ºC mas muitos tripomastigotas permaneceram circulando livremente nos soros por dois a três dias. A quantidade de soro imune capaz de lisar um máximo de 10 x 10 [elevado a 6] hemácias sensibilizadas não foi capaz de lisar 4 x 10 [elevado a 3] tripomastigotas. Tipicamente, os parasitos apresentavam alterações cíclicas com formação de

  6. Pig but not Human Interferon-γ Initiates Human Cell-Mediated Rejection of Pig Tissue in vivo

    Science.gov (United States)

    Sultan, Parvez; Murray, Allan G.; McNiff, Jennifer M.; Lorber, Marc I.; Askenase, Philip W.; Bothwell, Alfred L. M.; Pober, Jordan S.

    1997-08-01

    Split-thickness pig skin was transplanted on severe combined immunodeficient mice so that pig dermal microvessels spontaneously inosculated with mouse microvessels and functioned to perfuse the grafts. Pig endothelial cells in the healed grafts constitutively expressed class I and class II major histocompatibility complex molecules. Major histocompatibility complex molecule expression could be further increased by intradermal injection of pig interferon-γ (IFN-γ ) but not human IFN-γ or tumor necrosis factor. Grafts injected with pig IFN-γ also developed a sparse infiltrate of mouse neutrophils and eosinophils without evidence of injury. Introduction of human peripheral blood mononuclear cells into the animals by intraperitoneal inoculation resulted in sparse perivascular mononuclear cell infiltrates in the grafts confined to the pig dermis. Injection of pig skin grafts on mice that received human peripheral blood mononuclear cells with pig IFN-γ (but not human IFN-γ or heat-inactivated pig IFN-γ ) induced human CD4+ and CD8+ T cells and macrophages to more extensively infiltrate the pig skin grafts and injure pig dermal microvessels. These findings suggest that human T cell-mediated rejection of xenotransplanted pig organs may be prevented if cellular sources of pig interferon (e.g., passenger lymphocytes) are eliminated from the graft.

  7. Anti-DNA antibody mediated catalysis is isotype dependent.

    Science.gov (United States)

    Xia, Yumin; Eryilmaz, Ertan; Zhang, Qiuting; Cowburn, David; Putterman, Chaim

    2016-01-01

    Anti-DNA antibodies are the serological hallmark of systemic lupus erythematosus, and participate in the pathogenesis of lupus nephritis by cross-reacting with multiple renal antigens. Previously, using a panel of murine anti-DNA IgGs that share identical variable regions but that differ in the constant regions, we demonstrated that the cross-reaction and renal pathogenicity of anti-DNA antibodies are isotype dependent. In this study, we investigated the catalytic potential of this anti-DNA antibody panel, and determined its isotype dependency. The three isotype switch variants (IgG1, IgG2a, IgG2b) and the parent IgG3 PL9-11 anti-DNA antibodies were compared in their catalysis of 500 base pair linear double stranded DNA and a 12-mer peptide (ALWPPNLHAWVP), by gel analysis, MALDI-TOF mass spectrometry, and nuclear magnetic resonance spectroscopy. The binding affinity of anti-DNA antibodies to double stranded DNA and peptide antigens were assessed by ELISA and surface plasmon resonance. We found that the PL9-11 antibody isotypes vary significantly in their potential to catalyze the cleavage of both linear and double stranded DNA and the proteolysis of peptides. The degree of the cleavage and proteolysis increases with the incubation temperature and time. While different PL9-11 isotypes have the same initial attack sites within the ALWPPNLHAWVP peptide, there was no correlation between binding affinity to the peptide and proteolysis rates. In conclusion, the catalytic properties of anti-DNA antibodies are isotype dependent. This finding provides further evidence that antibodies that share the same variable region, but which have different constant regions, are functionally distinct. The catalytic effects modulated by antibody constant regions need to be considered in the design of therapeutic antibodies (abzymes) and peptides designed to block pathogenic autoantibodies.

  8. Disturbance Rejection

    OpenAIRE

    2005-01-01

    This interactive tutorial reviews the disturbance rejection capabilities of different feedback control schemes. The interactions in this tutorial involve students analyzing 4 cases of step-like disturbance rejection. ME2801 Introduction to Engineering System Dynamics

  9. CD47-signal regulatory protein-alpha (SIRP alpha) interactions form a barrier for antibody-mediated tumor cell destruction

    NARCIS (Netherlands)

    Zhao, Xi Wen; van Beek, Ellen M.; Schornagel, Karin; Van der Maaden, Hans; Van Houdt, Michel; Otten, Marielle A.; Finetti, Pascal; Van Egmond, Marjolein; Matozaki, Takashi; Kraal, Georg; Birnbaum, Daniel; van Elsas, Andrea; Kuijpers, Taco W.; Bertucci, Francois; van den Berg, Timo K.

    2011-01-01

    Monoclonal antibodies are among the most promising therapeutic agents for treating cancer. Therapeutic cancer antibodies bind to tumor cells, turning them into targets for immune-mediated destruction. We show here that this antibody-mediated killing of tumor cells is limited by a mechanism involving

  10. Antibody-mediated neutralization of virus is abrogated by mycoplasma.

    OpenAIRE

    Dickson, C; Elkington, J; Hales, A.; Weiss, R.

    1980-01-01

    The ability of a mouse mammary tumor cell line to abrogate antibody neutralization of vesicular stomatitis virus was shown to be due to the presence of mycoplasma. The mycoplasma was isolated from the cell line and typed as Mycoplasma orale. Colonies of this mycoplasma were used to deliberately infect cell cultures which then gained the capacity to reactivate antibody-neutralized virus. The extent of the reactivation depended on the source of neutralizing antiserum. Other species of mycoplasm...

  11. Chimeric mouse-human IgG1 antibody that can mediate lysis of cancer cells

    International Nuclear Information System (INIS)

    A chimeric mouse-human antibody has been created that recognizes an antigen found on the surface of cells from many carcinomas. Immunoglobulin constant (C) domains of the mouse monoclonal antibody L6, C/sub γ2a/ and C/sub kappa/, were substituted by the human C/sub γ1/ and C/sub kappa/ by recombining cDNA modules encoding variable or C domains. The cDNA constructs were transfected into lymphoid cells for antibody production. The chimeric antibody and mouse L6 antibody bound to carcinoma cells with equal affinity and mediated complement-dependent cytolysis. In the presence of human effector cells, the chimeric antibody gave antibody-dependent cellular cytotoxicity at 100 times lower concentration than that needed for the mouse L6 antibody. The assay for lysis was carried out with 51Cr-labeled target calls. The chimeric antibody, but not the mouse L6 antibody, is effective against a melanoma line expressing small amounts of the L6 antigen. The findings point to the usefulness of the chimeric antibody approach for obtaining agents with strong antitumor activity for possible therapeutic use in man

  12. Antibody-dependent cell-mediated cytotoxicity (ADCC) toward human O+ red cells coated with anti-D antibody: comparison between lymphocyte and monocyte ADCC activity.

    OpenAIRE

    Sunada,Mitsutoshi; Suzuki, Shinya; Ota, Zensuke

    1985-01-01

    We investigated the antibody dependent cell-mediated cytotoxicity (ADCC) of lymphocytes and monocytes toward human O+ red cells coated with anti-D antibody using a 51Cr release assay. Lysis of sensitized red cells by lymphocytes occurred rapidly, but monocyte-mediated lysis occurred slowly. This difference might be due to postphagocytic 51Cr release by monocytes. ADCC of lymphocytes increased in proportion to the effector cell number, but large amounts of antibodies were required. In contrast...

  13. Macrophage-Mediated Trogocytosis Leads to Death of Antibody-Opsonized Tumor Cells.

    Science.gov (United States)

    Velmurugan, Ramraj; Challa, Dilip K; Ram, Sripad; Ober, Raimund J; Ward, E Sally

    2016-08-01

    Understanding the complex behavior of effector cells such as monocytes or macrophages in regulating cancerous growth is of central importance for cancer immunotherapy. Earlier studies using CD20-specific antibodies have demonstrated that the Fcγ receptor (FcγR)-mediated transfer of the targeted receptors from tumor cells to these effector cells through trogocytosis can enable escape from antibody therapy, leading to the viewpoint that this process is protumorigenic. In the current study, we demonstrate that persistent trogocytic attack results in the killing of HER2-overexpressing breast cancer cells. Further, antibody engineering to increase FcγR interactions enhances this tumoricidal activity. These studies extend the complex repertoire of activities of macrophages to trogocytic-mediated cell death of HER2-overexpressing target cells and have implications for the development of effective antibody-based therapies. Mol Cancer Ther; 15(8); 1879-89. ©2016 AACR. PMID:27226489

  14. Iron as the Key Modulator of Hepcidin Expression in Erythroid Antibody-Mediated Hypoplasia

    Directory of Open Access Journals (Sweden)

    J. C. Fernandes

    2014-01-01

    Full Text Available Erythroid hypoplasia (EH is a rare complication associated with recombinant human erythropoietin (rHuEPO therapies, due to development of anti-rHuEPO antibodies; however, the underlying mechanisms remain poorly clarified. Our aim was to manage a rat model of antibody-mediated EH induced by rHuEPO and study the impact on iron metabolism and erythropoiesis. Wistar rats treated during 9 weeks with a high rHuEPO dose (200 IU developed EH, as shown by anemia, reduced erythroblasts, reticulocytopenia, and plasmatic anti-rHuEPO antibodies. Serum iron was increased and associated with mRNA overexpression of hepatic hepcidin and other iron regulatory mediators and downregulation of matriptase-2; overexpression of divalent metal transporter 1 and ferroportin was observed in duodenum and liver. Decreased EPO expression was observed in kidney and liver, while EPO receptor was overexpressed in liver. Endogenous EPO levels were normal, suggesting that anti-rHuEPO antibodies blunted EPO function. Our results suggest that anti-rHuEPO antibodies inhibit erythropoiesis causing anemia. This leads to a serum iron increase, which seems to stimulate hepcidin expression despite no evidence of inflammation, thus suggesting iron as the key modulator of hepcidin synthesis. These findings might contribute to improving new therapeutic strategies against rHuEPO resistance and/or development of antibody-mediated EH in patients under rHuEPO therapy.

  15. Diversification of the Primary Antibody Repertoire by AID-Mediated Gene Conversion.

    Science.gov (United States)

    Lanning, Dennis K; Knight, Katherine L

    2015-01-01

    Gene conversion, mediated by activation-induced cytidine deaminase (AID), has been found to contribute to generation of the primary antibody repertoire in several vertebrate species. Generation of the primary antibody repertoire by gene conversion of immunoglobulin (Ig) genes occurs primarily in gut-associated lymphoid tissues (GALT) and is best described in chicken and rabbit. Here, we discuss current knowledge of the mechanism of gene conversion as well as the contribution of the microbiota in promoting gene conversion of Ig genes. Finally, we propose that the antibody diversification strategy used in GALT species, such as chicken and rabbit, is conserved in a subset of human and mouse B cells.

  16. Molecular mechanisms of antibody-mediated neutralisation of flavivirus infection.

    Science.gov (United States)

    Pierson, Theodore C; Diamond, Michael S

    2008-01-01

    Flaviviruses are a group of positive-stranded RNA viruses that cause a spectrum of severe illnesses globally in more than 50 million individuals each year. While effective vaccines exist for three members of this group (yellow fever, Japanese encephalitis, and tick-borne encephalitis viruses), safe and effective vaccines for several other flaviviruses of clinical importance, including West Nile and dengue viruses, remain in development. An effective humoral immune response is critical for protection against flaviviruses and an essential goal of vaccine development. The effectiveness of virus-specific antibodies in vivo reflects their capacity to inhibit virus entry and spread through several mechanisms, including the direct neutralisation of virus infection. Recent advances in our understanding of the structural biology of flaviviruses, coupled with the use of small-animal models of flavivirus infection, have promoted significant advances in our appreciation of the factors that govern antibody recognition and inhibition of flaviviruses in vitro and in vivo. In this review, we discuss the properties that define the potency of neutralising antibodies and the molecular mechanisms by which they inhibit virus infection. How recent advances in this area have the potential to improve the development of safe and effective vaccines and immunotherapeutics is also addressed. PMID:18471342

  17. Mechanisms and Mediators of Inflammation: Potential Models for Skin Rejection and Targeted Therapy in Vascularized Composite Allotransplantation

    Directory of Open Access Journals (Sweden)

    Theresa Hautz

    2012-01-01

    Full Text Available Vascularized composite allotransplantation (VCA is an effective treatment option for patients suffering from limb loss or severe disfigurement. However, postoperative courses of VCA recipients have been complicated by skin rejection, and long-term immunosuppression remains a necessity for allograft survival. To widen the scope of this quality-of-life improving procedure minimization of immunosuppression in order to limit risks and side effects is needed. In some aspects, the molecular mechanisms and dynamics of skin allograft rejection seem similar to inflammatory skin conditions. T cells are key players in skin rejection and are recruited to the skin via activation of adhesion molecules, cytokines, and chemokines. Blocking these molecules has not only shown success in the treatment of inflammatory dermatoses, but also prolonged graft survival in various models of solid organ transplantation. In addition to T cell recruitment, ectopic lymphoid structures within the allograft associated with chronic rejection in solid organ transplantation might contribute to the strong alloimmune response towards the skin. Selectively targeting the molecules involved offers exciting novel therapeutic options in the prevention and treatment of skin rejection after VCA.

  18. HIV-Specific Antibody-Dependent Cellular Cytotoxicity (ADCC) -Mediating Antibodies Decline while NK Cell Function Increases during Antiretroviral Therapy (ART)

    DEFF Research Database (Denmark)

    Skov Jensen, Sanne; Fomsgaard, Anders; Borggren, Marie;

    2015-01-01

    Understanding alterations in HIV-specific immune responses during antiretroviral therapy (ART), such as antibody-dependent cellular cytotoxicity (ADCC), is important in the development of novel strategies to control HIV-1 infection. This study included 53 HIV-1 positive individuals. We evaluated...... the ability of effector cells and antibodies to mediate ADCC separately and in combination using the ADCC-PanToxiLux assay. The ability of the peripheral blood mononuclear cells (PBMCs) to mediate ADCC was significantly higher in individuals who had been treated with ART before seroconversion, compared...... to the individuals initiating ART at a low CD4+ T cell count (antibodies mediating ADCC declined...

  19. Rejecting Change

    Institute of Scientific and Technical Information of China (English)

    KERRY; BROWN

    2011-01-01

    British voters overwhelmingly reject an alternative voting system The British electorate,in only the second ever national referendum held in their history (the first was on joining the EU,over 35 years ago) rejected alterations to their voting system from the current first-past-the-post system to a form of alternative voting similar to that used

  20. Antibody-mediated phagocytosis contributes to the anti-tumor activity of the therapeutic antibody daratumumab in lymphoma and multiple myeloma

    DEFF Research Database (Denmark)

    Overdijk, M. B.; Verploegen, S.; Bogels, M.;

    2015-01-01

    Daratumumab (DARA) is a human CD38-specific IgG1 antibody that is in clinical development for the treatment of multiple myeloma (MM). The potential for IgG1 antibodies to induce macrophage-mediated phagocytosis, in combination with the known presence of macrophages in the tumor microenvironment i...

  1. Modalities for treatment of antisperm antibody mediated infertility: novel perspectives.

    Science.gov (United States)

    Naz, Rajesh K

    2004-05-01

    Immunoinfertility because of antisperm antibodies (ASA) is an important cause of infertility in humans. The incidence of ASA in infertile couples is 9-36% depending on the reporting center. Early claims regarding the incidence and involvement of ASA in involuntary infertility were probably overemphasized, which has resulted in subsequent confusion, doubt, and underestimation of their clinical significance. No immunoglobulin that binds to sperm should be called an antisperm antibody in a strict sense unless it is directed against a sperm antigen that plays a role in fertilization and fertility. ASA directed against the fertilization-related antigens are more relevant to infertility than the immunoglobulins that bind to sperm associated antigens. Several methods have been reported for treatment of immunoinfertility. These include: immunosuppressive therapies using corticosteroids or cyclosporine; assisted reproductive technologies such as intrauterine insemination, gamete intrafallopian transfer, in vitro fertilization, and intracytoplasmic sperm injection; laboratory techniques such as sperm washing, immunomagnetic sperm separation, proteolytic enzyme treatment, and use of immunobeads. Most of the available techniques have side effects, are invasive and expensive, have low efficacy, or provide conflicting results. Recent findings using defined sperm antigens that have a role in fertilization/fertility have provided animal models and innovative novel perspectives for studying the mechanism of immunoinfertility and possible modalities for treatment. The better understanding of local immunity and latest advances in hybridoma and recombinant technologies, proteomics and genomics leading to characterization of sperm antigens relevant to fertility will help to clarify the controversy and to establish the significance of ASA in infertility. PMID:15212677

  2. Antibody-dependent cellular cytotoxicity-mediating antibodies from an HIV-1 vaccine efficacy trial target multiple epitopes and preferentially use the VH1 gene family.

    Science.gov (United States)

    Bonsignori, Mattia; Pollara, Justin; Moody, M Anthony; Alpert, Michael D; Chen, Xi; Hwang, Kwan-Ki; Gilbert, Peter B; Huang, Ying; Gurley, Thaddeus C; Kozink, Daniel M; Marshall, Dawn J; Whitesides, John F; Tsao, Chun-Yen; Kaewkungwal, Jaranit; Nitayaphan, Sorachai; Pitisuttithum, Punnee; Rerks-Ngarm, Supachai; Kim, Jerome H; Michael, Nelson L; Tomaras, Georgia D; Montefiori, David C; Lewis, George K; DeVico, Anthony; Evans, David T; Ferrari, Guido; Liao, Hua-Xin; Haynes, Barton F

    2012-11-01

    The ALVAC-HIV/AIDSVAX-B/E RV144 vaccine trial showed an estimated efficacy of 31%. RV144 secondary immune correlate analysis demonstrated that the combination of low plasma anti-HIV-1 Env IgA antibodies and high levels of antibody-dependent cellular cytotoxicity (ADCC) inversely correlate with infection risk. One hypothesis is that the observed protection in RV144 is partially due to ADCC-mediating antibodies. We found that the majority (73 to 90%) of a representative group of vaccinees displayed plasma ADCC activity, usually (96.2%) blocked by competition with the C1 region-specific A32 Fab fragment. Using memory B-cell cultures and antigen-specific B-cell sorting, we isolated 23 ADCC-mediating nonclonally related antibodies from 6 vaccine recipients. These antibodies targeted A32-blockable conformational epitopes (n = 19), a non-A32-blockable conformational epitope (n = 1), and the gp120 Env variable loops (n = 3). Fourteen antibodies mediated cross-clade target cell killing. ADCC-mediating antibodies displayed modest levels of V-heavy (VH) chain somatic mutation (0.5 to 1.5%) and also displayed a disproportionate usage of VH1 family genes (74%), a phenomenon recently described for CD4-binding site broadly neutralizing antibodies (bNAbs). Maximal ADCC activity of VH1 antibodies correlated with mutation frequency. The polyclonality and low mutation frequency of these VH1 antibodies reveal fundamental differences in the regulation and maturation of these ADCC-mediating responses compared to VH1 bNAbs. PMID:22896626

  3. Mechanisms and Mediators of Inflammation: Potential Models for Skin Rejection and Targeted Therapy in Vascularized Composite Allotransplantation

    OpenAIRE

    Theresa Hautz; Dolores Wolfram; Johanna Grahammer; Ravi Starzl; Christoph Krapf; Johann Pratschke; ANDREW LEE, W. P.; Gerald Brandacher; Stefan Schneeberger

    2012-01-01

    Vascularized composite allotransplantation (VCA) is an effective treatment option for patients suffering from limb loss or severe disfigurement. However, postoperative courses of VCA recipients have been complicated by skin rejection, and long-term immunosuppression remains a necessity for allograft survival. To widen the scope of this quality-of-life improving procedure minimization of immunosuppression in order to limit risks and side effects is needed. In some aspects, the molecular mechan...

  4. Increasing the sensitivity of reverse phase protein arrays by antibody-mediated signal amplification

    Directory of Open Access Journals (Sweden)

    Brase Jan C

    2010-06-01

    Full Text Available Abstract Background Reverse phase protein arrays (RPPA emerged as a useful experimental platform to analyze biological samples in a high-throughput format. Different signal detection methods have been described to generate a quantitative readout on RPPA including the use of fluorescently labeled antibodies. Increasing the sensitivity of RPPA approaches is important since many signaling proteins or posttranslational modifications are present at a low level. Results A new antibody-mediated signal amplification (AMSA strategy relying on sequential incubation steps with fluorescently-labeled secondary antibodies reactive against each other is introduced here. The signal quantification is performed in the near-infrared range. The RPPA-based analysis of 14 endogenous proteins in seven different cell lines demonstrated a strong correlation (r = 0.89 between AMSA and standard NIR detection. Probing serial dilutions of human cancer cell lines with different primary antibodies demonstrated that the new amplification approach improved the limit of detection especially for low abundant target proteins. Conclusions Antibody-mediated signal amplification is a convenient and cost-effective approach for the robust and specific quantification of low abundant proteins on RPPAs. Contrasting other amplification approaches it allows target protein detection over a large linear range.

  5. Integrin Receptors on Tumor Cells Facilitate NK cell-mediated Antibody-dependent Cytotoxicity

    OpenAIRE

    Anikeeva, Nadia; Steblyanko, Maria; Fayngerts, Svetlana; Kopylova, Natalya; Marshall, Deborah J.; Powers, Gordon D.; Sato, Takami; Campbell, Kerry S.; Sykulev, Yuri

    2014-01-01

    NK cells that mediate ADCC play an important role in tumor-specific immunity. We have examined factors limiting specific lysis of tumor cells by CD16.NK-92 cells induced by CNTO 95LF antibodies recognizing αV integrins that are overexpressed on many tumor cells. Although all tested tumor cells were killed by CD16.NK-92 effectors in the presence of the antibodies, the killing of target cells with a low level of ICAM-1 expression revealed a dramatic decrease in their specific lysis at high anti...

  6. Antibody to collapsin response mediator protein 1 promotes neurite outgrowth from rat hippocampal neurons

    Institute of Scientific and Technical Information of China (English)

    Hongsheng Lin; Jing Chen; Wenbin Zhang; Xiaobing Gong; Biao Chen; Guoqing Guo

    2011-01-01

    This study examined the role of collapsin response mediator protein 1 (CRMP-1) on neurite outgrowth from rat hippocampal neurons by blocking its function using an antibody. Hippocampal neurons, cultured in vitro, were treated (blocked) using a polyclonal antibody to CRMP-1, and neurite outgrowth and cytoskeletal changes w ere captured using atomic force microscopy and laser confocal microscopy. Control cells, treated with normal rabbit IgG, established their characteristic morphology and had a large number of processes emerging from the soma, including numerous branches. Microtubules were clearly visible in the soma, formed an elaborate network, and were aligned in parallel arrays to form bundles which projected into neurites. After blocking with CRMP-1 antibody, the number of branches emerging from axons and dendrites significantly increased and were substantially longer, compared with control cells. However, the microtubule network nearly disappeared and only a few remnants were visible. When CRMP-1 antibody-blocked neurons were treated with the Rho inhibitor, Y27632, numerous neurites emerged from the soma, and branches were more abundant than in control neurons. Although the microtubules were not as clearly visible compared with neurons cultured in control medium, the microtubule network recovered in cells treated with Y27632, when compared with cells that were blocked by CRMP-1 antibody (but not treated with Y27632). These results demonstrate that neurite outgrowth from hippocampal neurons can be promoted by blocking CRMP-1 with a polyclonal antibody.

  7. The Fc and not CD4 Receptor Mediates Antibody Enhancement of HIV Infection in Human Cells

    Science.gov (United States)

    Homsy, Jacques; Meyer, Mia; Tateno, Masatoshi; Clarkson, Sarah; Levy, Jay A.

    1989-06-01

    Antibodies that enhance human immunodeficiency virus (HIV) infectivity have been found in the blood of infected individuals and in infected or immunized animals. These findings raise serious concern for the development of a safe vaccine against acquired immunodeficiency syndrome. To address the in vivo relevance and mechanism of this phenomenon, antibody-dependent enhancement of HIV infectivity in peripheral blood macrophages, lymphocytes, and human fibroblastoid cells was studied. Neither Leu3a, a monoclonal antibody directed against the CD4 receptor, nor soluble recombinant CD4 even at high concentrations prevented this enhancement. The addition of monoclonal antibody to the Fc receptor III (anti-FcRIII), but not of antibodies that react with FcRI or FcRII, inhibited HIV type 1 and HIV type 2 enhancement in peripheral blood macrophages. Although enhancement of HIV infection in CD4+ lymphocytes could not be blocked by anti-FcRIII, it was inhibited by the addition of human immunoglobulin G aggregates. The results indicate that the FcRIII receptor on human macrophages and possibly another Fc receptor on human CD4+ lymphocytes mediate antibody-dependent enhancement of HIV infectivity and that this phenomenon proceeds through a mechanism independent of the CD4 protein.

  8. Ibrutinib interferes with the cell-mediated anti-tumor activities of therapeutic CD20 antibodies: implications for combination therapy

    DEFF Research Database (Denmark)

    Da Roit, F.; Engelberts, P. J.; Taylor, R. P.;

    2015-01-01

    the possible positive or negative impact of these drugs on all known mechanisms of action of both type I and type II anti-CD20 antibodies. Pretreatment with ibrutinib for 1 hour did not increase direct cell death of cell lines or chronic lymphocytic leukemia samples mediated by anti-CD20 antibodies. Pre......-treatment with ibrutinib did not inhibit complement activation or complement-mediated lysis. In contrast, ibrutinib strongly inhibited all cell-mediated mechanisms induced by anti-CD20 antibodies rituximab, ofatumumab or obinutuzumab, either in purified systems or whole blood assays. Activation of natural killer cells...

  9. Impaired antibody-dependent cellular cytotoxicity mediated by herceptin in patients with gastric cancer.

    Science.gov (United States)

    Kono, Koji; Takahashi, Akihiro; Ichihara, Fumiko; Sugai, Hidemitsu; Fujii, Hideki; Matsumoto, Yoshirou

    2002-10-15

    The humanized monoclonal antibody Herceptin, which specifically targets HER-2/neu, exhibits growth inhibitory activity against HER-2/neu-overexpressing tumors and is approved for therapeutic use with proved survival benefit in patients with HER-2/neu-positive breast cancer. In the present study, we investigated whether Herceptin could affect the HER-2/neu-overexpressing gastric cancer cells based on antibody-dependent cell-mediated cytotoxicity (ADCC) and compared immune effector cells from gastric cancer patients with normal individuals on ADCC. HER-2/neu-expressing gastric cancer cells could be killed by Herceptin-mediated ADCC and the Herceptin-induced ADCC correlated with the degree of HER-2/neu expression on the gastric cancer cells. However, the Herceptin-mediated ADCC was significantly impaired in peripheral blood mononuclear cells from advanced disease patients (n = 10) compared with that in early disease (n = 12; P = 0.04) or healthy individuals (n = 10, P = 0.02). Moreover, natural killer (NK) cells purified from patients with advanced disease indicated less Herceptin-mediated ADCC in comparison with that from healthy donors (P = 0.04), whereas monocytes purified from the patients showed an almost equal amount of Herceptin-mediated ADCC in comparison with that from healthy individuals, indicating that NK cell dysfunction contributed to the impaired Herceptin-mediated ADCC in gastric cancer patients. Furthermore, the NK-cell dysfunction on Herceptin-mediated ADCC correlated with the down-regulation of CD16zeta expression in the patients, and interleukin 2 ex vivo treatment of NK cells could restore the impairment of Herceptin-mediated ADCC, concomitant to the normalization of the expression of CD16zeta molecules. Thus, some modalities such as interleukin 2 treatment aimed at reversing NK dysfunction may be necessary for successful Herceptin treatment of gastric cancer. PMID:12384543

  10. Mechanistic studies of antibody mediated clearance of tau aggregates using an ex vivo brain slice model

    Directory of Open Access Journals (Sweden)

    Pavan eKrishnamurthy

    2011-10-01

    Full Text Available Recent studies have shown that immunotherapy clears amyloid beta (A plaques and reduces A levels in mouse models of Alzheimer’s disease (AD, as well as in AD patients. Tangle pathology is also relevant for the neurodegeneration in AD, and our studies have shown that active immunization with an AD related phospho-tau peptide reduces aggregated tau within the brain and slows the progression of tauopathy-induced behavioural impairments. Thus, clearance of neurofibrillary tangles and/or their precursors may reduce synaptic and neuronal loss associated with AD and other tauopathies. So far the mechanisms involved in antibody-mediated clearance of tau pathology are yet to be elucidated. In this study we have used a mouse brain slice model to examine the uptake and localization of FITC labeled anti-tau antibodies. Confocal microscopy analysis showed that the FITC labelled anti-tau antibody co-stained with phosphorylated tau, had a perinuclear appearance and co-localised with markers of the endosomal/lysosomal pathway. Additionally, tau and FITC IgG were found together in an enriched lysosome fraction. In summary, antibody-mediated clearance of intracellular tau aggregates appears to occur via the lysosomal pathway.

  11. The importance of non-HLA antibodies in transplantation.

    Science.gov (United States)

    Zhang, Qiuheng; Reed, Elaine F

    2016-08-01

    The development of post-transplantation antibodies against non-HLA autoantigens is associated with rejection and decreased long-term graft survival. Although our knowledge of non-HLA antibodies is incomplete, compelling experimental and clinical findings demonstrate that antibodies directed against autoantigens such as angiotensin type 1 receptor, perlecan and collagen, contribute to the process of antibody-mediated acute and chronic rejection. The mechanisms that underlie the production of autoantibodies in the setting of organ transplantation is an important area of ongoing investigation. Ischaemia-reperfusion injury, surgical trauma and/or alloimmune responses can result in the release of organ-derived autoantigens (such as soluble antigens, extracellular vesicles or apoptotic bodies) that are presented to B cells in the context of the transplant recipient's antigen presenting cells and stimulate autoantibody production. Type 17 T helper cells orchestrate autoantibody production by supporting the proliferation and maturation of autoreactive B cells within ectopic tertiary lymphoid tissue. Conversely, autoantibody-mediated graft damage can trigger alloimmunity and the development of donor-specific HLA antibodies that can act in synergy to promote allograft rejection. Identification of the immunologic phenotypes of transplant recipients at risk of non-HLA antibody-mediated rejection, and the development of targeted therapies to treat such rejection, are sorely needed to improve both graft and patient survival. PMID:27345243

  12. Oxygen dependence of human alveolar macrophage-mediated antibody-dependent cytotoxicity.

    OpenAIRE

    Conkling, P.; Papermaster-Bender, G; Whitcomb, M; Sagone, A L

    1982-01-01

    We studied the metabolic characteristics of the human alveolar macrophage-mediated antibody-dependent cytotoxicity (ADCC) reaction, using an anti-D sensitized human erythrocyte target system. Metabolic experiments demonstrated a high resting rate of glucose metabolism in macrophages, but no oxidative metabolic burst was found to accompany the ADCC reaction. These findings were confirmed by oxygen consumption studies, showing a high resting rate of oxygen consumption by macrophages, but no cha...

  13. Significance of MICA antibody monitoring in management of acute and chronic rejection af-ter renal transplantation%MICA抗体监测在肾移植术后急、慢性排斥反应中的意义

    Institute of Scientific and Technical Information of China (English)

    丁小明; 焦凤梅; 王晓红; 薛武军; 田普训; 李杨; 田晓辉

    2013-01-01

    Objective To evaluate the association of major histocompatibility complex class I chain related gene A (MICA) antibodies with acute rejection (AR), chronic rejection (CR) and renal function after renal transplantation. Methods Serum MICA antibodies were detected with ELISA before and after transplantation with also examinations of panel reactive antibodies (PRA), serum creatinine, urine, graft ultrasound, lymphocyte subsets and the pathology of graft biopsy. The study was carried out in two parts to monitor MICA antibodies in acute and chronic rejections after renal transplantation. Results In the first part of the study 18 of the 41 recipients experienced episodes of acute rejection, and the incidence rate was markedly higher in MICA+group than in MICA-group (P<0.05). Compared with the recipients with stable renal functions, the patients with acute graft rejection showed a significantly higher positivity rate of MICA antibodies. Postoperative MICA antibody monitoring showed that MICA antibody level increased gradually 2-3 days after the occurrence of acute rejection; anti-rejection treatment lowered serum creatinine to a normal level but MICA antibodies remained positive. In the second part, 21 of 40 patients had chronic graft rejection and showed significantly higher positivity rate of MICA than the patients with stable renal functions (P<0.05). In patients with chronic rejections, the serum creatinine levels were significantly higher in MICA+than in MICA-cases (P<0.05). Graft biopsy of all MICA+cases showed C4d deposition. Conclusion The status of MICA antibodies can predict the occurrence and treatment outcomes of acute rejection, and also as one of the major causes of chronic graft rejection, they affect the long-term survival of the renal grafts.%目的探讨肾移植受者的抗MICA抗体水平与急性和慢性排斥反应的相关性及其对移植肾功能的影响。方法采用酶联免疫吸附方法检测接受同种异体肾移植手术的患者血

  14. Measurement of Anti-Erythropoiesis-Stimulating Agent IgG4 Antibody as an Indicator of Antibody-Mediated Pure Red Cell Aplasia

    Science.gov (United States)

    Weeraratne, Dohan K.; Kuck, Andrew J.; Chirmule, Narendra

    2013-01-01

    Patients treated with erythropoietin-based erythropoiesis-stimulating agents (ESAs) can develop a rare but life-threatening condition called antibody-mediated pure red cell aplasia (amPRCA). The antibody characteristics in a nephrology patient with amPRCA include high antibody concentrations with neutralizing activity and a mixed IgG subclass including anti-ESA IgG4 antibodies. In contrast, anti-ESA IgG4 antibody is generally not detected in baseline samples and antibody-positive non-PRCA patients. Therefore, we validated a highly sensitive immunoassay on the ImmunoCAP 100 instrument to quantitate anti-ESA IgG4 antibodies using a human recombinant anti-epoetin alfa (EPO) IgG4 antibody as a calibrator. The biotinylated ESA was applied to a streptavidin ImmunoCAP, and bound anti-ESA IgG4 antibodies were detected using a β-galactosidase-conjugated mouse anti-human IgG4 antibody. The validated assay was used to detect anti-ESA IgG4 in amPRCA and non-PRCA patients. The immunoassay detected 15 ng/ml of human anti-EPO IgG4 antibody in the presence of a 200 M excess of human anti-ESA IgG1, IgG2, or IgM antibody and tolerated 2 μg/ml of soluble erythropoietin. All patient samples with confirmed amPRCA had measurable anti-ESA IgG4 antibodies. In addition, 94% (17/18) of non-PRCA patient samples were antibody negative or had below 15 ng/ml of anti-ESA IgG4 antibodies. This novel immunoassay can measure low-nanogram quantities of human anti-ESA IgG4 antibodies in the presence of other anti-ESA antibodies. An increased concentration of anti-ESA IgG4 antibody is associated with the development of amPRCA. We propose that the measurement of anti-ESA specific IgG4 antibodies may facilitate early detection of amPRCA in patients receiving all ESAs structurally related to human erythropoietin. PMID:23114696

  15. Integrin receptors on tumor cells facilitate NK cell-mediated antibody-dependent cytotoxicity.

    Science.gov (United States)

    Anikeeva, Nadia; Steblyanko, Maria; Fayngerts, Svetlana; Kopylova, Natalya; Marshall, Deborah J; Powers, Gordon D; Sato, Takami; Campbell, Kerry S; Sykulev, Yuri

    2014-08-01

    NK cells that mediate ADCC play an important role in tumor-specific immunity. We have examined factors limiting specific lysis of tumor cells by CD16.NK-92 cells induced by CNTO 95LF antibodies recognizing αV integrins that are overexpressed on many tumor cells. Although all tested tumor cells were killed by CD16.NK-92 effectors in the presence of the antibodies, the killing of target cells with a low level of ICAM-1 expression revealed a dramatic decrease in their specific lysis at high antibody concentration, revealing a dose limiting effect. A similar effect was also observed with primary human NK cells. The effect was erased after IFN-γ treatment of tumor cells resulting in upregulation of ICAM-1. Furthermore, killing of the same tumor cells induced by Herceptin antibody was significantly impaired in the presence of CNTO 95Ala-Ala antibody variant that blocks αV integrins but is incapable of binding to CD16. These data suggest that αV integrins on tumor cells could compensate for the loss of ICAM-1 molecules, thereby facilitating ADCC by NK cells. Thus, NK cells could exercise cytolytic activity against ICAM-1 deficient tumor cells in the absence of proinflammatory cytokines, emphasizing the importance of NK cells in tumor-specific immunity at early stages of cancer. PMID:24810893

  16. Antibody-mediated immune suppression is improved when blends of anti-RBC monoclonal antibodies are used in mice.

    Science.gov (United States)

    Bernardo, Lidice; Amash, Alaa; Marjoram, Danielle; Lazarus, Alan H

    2016-08-25

    Although the prevention of hemolytic disease of the fetus and newborn is highly effective using polyclonal anti-D, a recombinant alternative is long overdue. Unfortunately, anti-D monoclonal antibodies have been, at best, disappointing. To determine the primary attribute defining an optimal antibody, we assessed suppression of murine red blood cell (RBC) immunization by single-monoclonal antibodies vs defined blends of subtype-matched antibodies. Allogeneic RBCs expressing the HOD antigen (hen egg lysozyme [HEL]-ovalbumin-human transmembrane Duffy(b)) were transfused into naïve mice alone or together with selected combinations of HEL-specific antibodies, and the resulting suppressive effect was assessed by evaluating the antibody response. Polyclonal HEL antibodies dramatically inhibited the antibody response to the HOD antigen, whereas single-monoclonal HEL antibodies were less effective despite the use of saturating doses. A blend of monoclonal HEL-specific antibodies reactive with different HEL epitopes significantly increased the suppressive effect, whereas a blend of monoclonal antibodies that block each other's binding to the HEL protein did not increase suppression. In conclusion, these data show that polyclonal antibodies are superior to monoclonal antibodies at suppressing the immune response to the HOD cells, a feature that can be completely recapitulated using monoclonal antibodies to different epitopes. PMID:27330002

  17. Cross-neutralization of influenza A viruses mediated by a single antibody loop.

    Science.gov (United States)

    Ekiert, Damian C; Kashyap, Arun K; Steel, John; Rubrum, Adam; Bhabha, Gira; Khayat, Reza; Lee, Jeong Hyun; Dillon, Michael A; O'Neil, Ryann E; Faynboym, Aleksandr M; Horowitz, Michael; Horowitz, Lawrence; Ward, Andrew B; Palese, Peter; Webby, Richard; Lerner, Richard A; Bhatt, Ramesh R; Wilson, Ian A

    2012-09-27

    Immune recognition of protein antigens relies on the combined interaction of multiple antibody loops, which provide a fairly large footprint and constrain the size and shape of protein surfaces that can be targeted. Single protein loops can mediate extremely high-affinity binding, but it is unclear whether such a mechanism is available to antibodies. Here we report the isolation and characterization of an antibody called C05, which neutralizes strains from multiple subtypes of influenza A virus, including H1, H2 and H3. X-ray and electron microscopy structures show that C05 recognizes conserved elements of the receptor-binding site on the haemagglutinin surface glycoprotein. Recognition of the haemagglutinin receptor-binding site is dominated by a single heavy-chain complementarity-determining region 3 loop, with minor contacts from heavy-chain complementarity-determining region 1, and is sufficient to achieve nanomolar binding with a minimal footprint. Thus, binding predominantly with a single loop can allow antibodies to target small, conserved functional sites on otherwise hypervariable antigens. PMID:22982990

  18. Quantitative evaluation of fucose reducing effects in a humanized antibody on Fcγ receptor binding and antibody-dependent cell-mediated cytotoxicity activities.

    Science.gov (United States)

    Chung, Shan; Quarmby, Valerie; Gao, Xiaoying; Ying, Yong; Lin, Linda; Reed, Chae; Fong, Chris; Lau, Wendy; Qiu, Zhihua J; Shen, Amy; Vanderlaan, Martin; Song, An

    2012-01-01

    The presence or absence of core fucose in the Fc region N-linked glycans of antibodies affects their binding affinity toward FcγRIIIa as well as their antibody-dependent cell-mediated cytotoxicity (ADCC) activity. However, the quantitative nature of this structure-function relationship remains unclear. In this study, the in vitro biological activity of an afucosylated anti-CD20 antibody was fully characterized. Further, the effect of fucose reduction on Fc effector functions was quantitatively evaluated using the afucosylated antibody, its "regular" fucosylated counterpart and a series of mixtures containing varying proportions of "regular" and afucosylated materials. Compared with the "regular" fucosylated antibody, the afucosylated antibody demonstrated similar binding interactions with the target antigen (CD20), C1q and FcγRIa, moderate increases in binding to FcγRIIa and IIb, and substantially increased binding to FcγRIIIa. The afucosylated antibodies also showed comparable complement-dependent cytotoxicity activity but markedly increased ADCC activity. Based on EC 50 values derived from dose-response curves, our results indicate that the amount of afucosylated glycan in antibody samples correlate with both FcγRIIIa binding activity and ADCC activity in a linear fashion. Furthermore, the extent of ADCC enhancement due to fucose depletion was not affected by the FcγRIIIa genotype of the effector cells.

  19. Renal and urinary levels of endothelial protein C receptor correlate with acute renal allograft rejection.

    Directory of Open Access Journals (Sweden)

    Lionel Lattenist

    Full Text Available The Endothelial Protein C Receptor (EPCR is expressed on leukocytes, on endothelium of large blood vessels and to a lesser extent on capillaries. Membrane bound EPCR plays an important role in the activation of protein C which has anticoagulant, anti-inflammatory and cytoprotective effects. After cleavage by a protease EPCR is also found as a soluble protein. Acute rejection of kidney allografts can be divided in T-cell-mediated rejection (TCMR and antibody-mediated (ABMR rejection. The latter is characterized by strong activation of coagulation. Currently no reliable non-invasive biomarkers are available to monitor rejection. Renal biopsies were available from 81 renal transplant patients (33 without rejection, 26 TCMR and 22 ABMR, we had access to mRNA material, matched plasma and urine samples for a portion of this cohort. Renal EPCR expression was assessed by RT-PCR and immunostaining. Plasma and urine sEPCR levels were measured by ELISA. ABMR patients showed higher levels of EPCR mRNA than TCMR patients. EPCR expression on glomeruli was significantly elevated in ABMR patients than in TCMR or control patients. In the peritubular capillaries EPCR expression was higher in ABMR patients than in control patients. EPCR expression was higher in tubules and arteries of rejection patients than in control patients. Plasma sEPCR levels did not differ. Urine sEPCR levels were more elevated in the ABMR group than in patients with TCMR or without rejection. ROC analysis demonstrated that urinary sEPCR is appropriate to discriminate between ABMR patients and TCMR or control patients. We conclude that urinary sEPCR could be a novel non-invasive biomarker of antibody mediated rejection in renal transplantation.

  20. Monoclonal Antibodies Recognizing HIV-1 gp41 Could Inhibit Env-Mediated Syncytium Formation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Geng; CHEN Yinghua

    2005-01-01

    Some monoclonal antibodies (mAbs) could inhibit infection by HIV-1. In this study, four mAbs against HIV-1 gp41 were prepared in mice. All four mAbs could bind to the recombinant soluble gp41 and recognize the native envelope glycoprotein gp160 expressed on the HIV-Env+ CHO-WT cell in flow cytometry analysis. Interestingly, the results show that all four mAbs purified by affinity chromatography could inhibit HIV-1 Env-mediated membrane fusion (syncytium formation) by 40%-60% at 10 μg/mL, which implies potential inhibitory activities against HIV-1.

  1. Antibody-Dependent Cell-Mediated Cytotoxicity Effector-Enhanced EphA2 Agonist Monoclonal Antibody Demonstrates Potent Activity against Human Tumors

    Directory of Open Access Journals (Sweden)

    Elizabeth M. Bruckheimer

    2009-06-01

    Full Text Available EphA2 is a receptor tyrosine kinase that has been shown to be overexpressed in a variety of human tumor types. Previous studies demonstrated that agonist monoclonal antibodies targeting EphA2 induced the internalization and degradation of the receptor, thereby abolishing its oncogenic effects. In this study, the in vitro and in vivo antibody-dependent cell-mediated cytotoxicity (ADCC activity of EphA2 effector-enhanced agonist monoclonal antibodies was evaluated. With tumor cell lines and healthy human peripheral blood monocytes, the EphA2 antibodies demonstrated ∼80% tumor cell killing. In a dose-dependent manner, natural killer (NK cells were required for the in vitro ADCC activity and became activated as demonstrated by the induction of cell surface expression of CD107a. To assess the role of NK cells on antitumor efficacy in vivo, the EphA2 antibodies were evaluated in xenograft models in severe compromised immunodeficient (SCID mice (which have functional NK cells and monocytes and SCID nonobese diabetic (NOD mice (which largely lack functional NK cells and monocytes. Dosing of EphA2 antibody in the SCID murine tumor model resulted in a 6.2-fold reduction in tumor volume, whereas the SCID/nonobese diabetic model showed a 1.6-fold reduction over the isotype controls. Together, these results demonstrate that the anti-EphA2 monoclonal antibodies may function through at least two mechanisms of action: EphA2 receptor activation and ADCC-mediated activity. These novel EphA2 monoclonal antibodies provide additional means by which host effector mechanisms can be activated for selective destruction of EphA2-expressing tumor cells.

  2. Currently available useful immunohistochemical markers of renal pathology for the diagnosis of renal allograft rejection.

    Science.gov (United States)

    Kanzaki, Go; Shimizu, Akira

    2015-07-01

    Renal allograft dysfunction may be induced by various causes, including alloimmune rejection, viral infection, urinary tract obstruction, calcineurin inhibitor nephrotoxicity and/or recurrent renal disease. In order to determine the underlying cause, a renal biopsy is performed and the renal transplant pathology is diagnosed using the internationally consensus Banff classification. Although a progressive understanding of allograft rejection has provided numerous immunohistochemical markers, only the C4d is regarded to be a sufficiently useful marker for antibody-mediated allograft rejection according to the Banff classification. This review summarizes currently available useful immunohistochemical markers of renal transplant pathology, including C4d, with diagnostic implications for human renal allograft rejection. In particular, we discuss immunohistochemical markers in the following three categories: immunohistochemical markers of renal pathology used to (i) analyze the mechanisms of alloimmune rejection, (ii) monitor cell injury and/or inflammation associated with rejection and (iii) identify renal components in order to improve the diagnosis of rejection. In addition, recent progress in the field of renal transplant pathology includes the development of a new method for assessing molecular pathology using OMICS analyses. As the recent findings of various studies in patients undergoing renal transplantation are very encouraging, novel immunohistochemical markers must be also developed and combined with new technologies for the diagnosis of human renal allograft rejection.

  3. Antibody-mediated neutralization of myelin-associated EphrinB3 accelerates CNS remyelination.

    Science.gov (United States)

    Syed, Yasir A; Zhao, Chao; Mahad, Don; Möbius, Wiebke; Altmann, Friedrich; Foss, Franziska; Sentürk, Aycan; Acker-Palmer, Amparo; Lubec, Gert; Lilley, Kathryn; Franklin, Robin J M; Nave, Klaus-A; Kotter, Mark R N

    2016-02-01

    Remyelination in multiple sclerosis (MS) lesions often remains incomplete despite the presence of oligodendrocyte progenitor cells (OPCs). Amongst other factors, successful remyelination depends on the phagocytic clearance of myelin debris. However, the proteins in myelin debris that act as potent and selective inhibitors on OPC differentiation and inhibit CNS remyelination remain unknown. Here, we identify the transmembrane signalling protein EphrinB3 as important mediator of this inhibition, using a protein analytical approach in combination with a primary rodent OPC assay. In the presence of EphrinB3, OPCs fail to differentiate. In a rat model of remyelination, infusion of EphrinB3 inhibits remyelination. In contrast, masking EphrinB3 epitopes using antibodies promotes remyelination. Finally, we identify EphrinB3 in MS lesions and demonstrate that MS lesion extracts inhibit OPC differentiation while antibody-mediated masking of EphrinB3 epitopes promotes it. Our findings suggest that EphrinB3 could be a target for therapies aiming at promoting remyelination in demyelinating disease. PMID:26687980

  4. RNAi-mediated silencing of HLA A2 suppressed acute rejection against human fibroblast xenografts in the striatum of 6-OHDA lesioned rats.

    Science.gov (United States)

    Liang, Caixia; Xu, Yunzhi; Zheng, Deyu; Sun, Xiaohong; Xu, Qunyuan; Duan, Deyi

    2016-08-15

    Major histocompatibility complex class l (MHC I) molecules play a role in determining whether transplanted cells will be accepted or rejected, and masking of MHC I on donor cells has been found useful for immunoprotection of neural xenografts. In the present study, primary human embryonic lung fibroblasts (HELF), HELF treated with lentivirus-mediated small interfering RNAs (siRNAs) targeting human leukocyte antigen A2 (HLA A2, MHC I in humans) (siHELF), and rat embryonic lung fibroblasts (RELF) were stereotaxically grafted into the striatum of 6-hydroxydopamine lesioned rats to explore whether knockdown of HLA A2 could reduce host immune responses against xenografts. Before lentiviral infection, the cells were transduced with retroviruses harboring tyrosine hydroxylase cDNA. Knockdown of HLA A2 protein was examined by Western blotting. The immune responses (the number of CD4 and CD8 T-cells in the brain and peripheral blood), glial reaction, and survival of human fibroblasts were quantitatively evaluated by flow cytometry and immunohistochemistry at 4d, 2w, and 6w post-graft. Animal behaviors were assessed by counting apomorphine-induced rotations pre- and post-grafts. It was shown that a lower level of HLA A2 was observed in siHELF grafts than in HELF grafts, and knockdown of HLA A2 decreased rat immune responses, as indicated by less remarkable increases in the number of CD8 and CD4 T-cells in the brain and the ratio of CD4:CD8 T-cells in the peripheral blood in rats grafted with siHELF. Rats grafted with siHELF exhibited a significant improvement in motor asymmetry post-transplantation and a better survival of human fibroblasts at 2w. The increasing number of activated microglia and the decreasing number of astrocytes were found in three groups of rats post-implantation. These data suggested that RNAi-mediated knockdown of HLA A2 could suppress acute rejection against xenogeneic human cell transplants in the rat brain. PMID:27397073

  5. A breakthrough in antibody-drug conjugates in anti-immune rejection%抗免疫排斥反应中抗体药物偶联物的突破性进展

    Institute of Scientific and Technical Information of China (English)

    郭彩龙; 莽源祎; 张雷

    2014-01-01

    BACKGROUND:The immunological rejection between host and graft is the leading cause of organ transplantation failure. The traditional immunosuppressive agents have been unable to meet the needs of clinical treatment. Antibody-drug conjugate, as a type of new drugs, may be hope for the treatment of immune rejection. OBJECTIVE:To comprehensively analyze the composition of antibody-drug conjugates, mechanism of action, clinical research progress as wel as the development trend. METHODS:A computer-based online retrieval was performed to search papers in CNKI and PubMed database using the key words of ADCs, immunosuppressive agents, immunotoxins, organ transplantation, graft rejection in Chinese and English. Recently published or published in the prestigious journals were selected in the same field. After excluding objective-independent papers and repeated studies, 42 papers were included for further analysis. RESULTS AND CONCLUSION:Antibody-drug conjugates, as highly effective and lowly toxic immunosuppressant, have achieved a breakthrough in treatment of targeting tumor, while the role of it in anti-immune rejection is stil at the exploratory stage. For islet transplantation, novel antibody-drug conjugates are required to block CD8+T effector by CD103/E-Cadherin pathway, and wil probably serve as a potential drug intervention for al ograft rejection.%背景:宿主与移植物间的免疫排斥反应是器官移植失败的主要原因之一,传统的免疫抑制剂已无法满足临床治疗的需求,抗体药物偶联物作为一类新型药物,可能为免疫排斥反应的治疗带来希望。  目的:综合分析抗体药物偶联物的构成、作用机制、临床研究进展以及未来的发展趋势。  方法:以“抗体药物偶联物、免疫抑制剂、免疫毒素、器官移植、移植物排斥”,“ADCs,immunosuppressive agents,immunotoxins,organ transplantation,graft rejection”为检索

  6. Resolution of acute malarial infections by T cell-dependent non-antibody-mediated mechanisms of immunity.

    OpenAIRE

    Cavacini, L A; Parke, L A; Weidanz, W P

    1990-01-01

    While it is generally accepted that acute blood stage malarial infections are resolved through the actions of protective antibodies, we observed that resistance to acute infection with Plasmodium chabaudi adami was mediated by T cell-dependent cellular immune mechanisms independent of antibody. We now report that acute blood stage infections caused by three additional murine hemoprotozoan parasites, Plasmodium vinckei petteri, Plasmodium chabaudi chabaudi, and Babesia microti, appear to be co...

  7. CARDIAC TRANSPLANT REJECTION AND NON-INVASIVE COMON CAROTID ARTERY WALL FUNCTIONAL INDICES

    Directory of Open Access Journals (Sweden)

    A. O. Shevchenko

    2015-01-01

    Full Text Available Allograft rejection would entail an increase in certain blood biomarkers and active substances derived from activated inflammatory cells which could influence entire vascular endothelial function and deteriorate arterial wall stiffness. We propose that carotid wall functional indices measured with non-invasive ultrasound could we valuable markers of the subclinical cardiac allograft rejection. Aim. Our goal was to analyze the clinical utility of functional common carotid wall (CCW variables measured with high-resolution Doppler ultrasound as a non-invasive screening tool for allograft rejection in cardiac transplant patients (pts. Methods. One hundred and seventy one pts included 93 cardiac recipients, 30 dilated cardiomyopathy waiting list pts, and 48 stable coronary artery disease (SCAD pts without decompensated heart failure were included. Along with resistive index (Ri, pulsative index (Pi, and CCW intima-media thickness (IMT, CCW rigidity index (iRIG was estimated using empirical equation. Non-invasive evaluation was performed in cardiac transplant recipients prior the endomyo- cardial biopsy. Results. Neither of Ri, Pi, or CCW IMT were different in studied subgroups. iRIG was signifi- cantly lower in SCAD pts when compared to the dilated cardiomyopathy subgroup. The later had similar values with cardiac transplant recipients without rejection. Antibody-mediated and cellular rejection were found in 22 (23.7% and 17 (18.3% cardiac recipients, respectively. Mean iRIG in pts without rejection was significantly lower in comparison to antibody-mediated rejection and cell-mediated (5514.7 ± 2404.0 vs 11856.1 ± 6643.5 and 16071.9 ± 10029.1 cm/sec2, respectively, p = 0.001. Area under ROC for iRIG was 0.90 ± 0.03 units2. Analysis showed that iRIG values above estimated treshold 7172 cm/sec2 suggested relative risk of any type of rejection 17.7 (95%CI = 6.3–49.9 sensitivity 80.5%, specificity – 81.1%, negative predictive value – 84

  8. Lung injury mediated by antibodies to endothelium. II. Study of the effect of repeated antigen-antibody interactions in rabbits tolerant to heterologous antibody.

    OpenAIRE

    Camussi, G.; Caldwell, P. R.; Andres, G.; Brentjens, J. R.

    1987-01-01

    The effect of repeated interactions of antibodies with cell surface antigens have been examined in in vitro, but not in in vivo systems. In this study are described the results of multiple antibody-cell surface antigen interactions in vivo. Rabbits were given repeated intravenous injections of goat antibodies to angiotensin converting enzyme (ACE), an antigen expressed on the surface of lung endothelial cells. For prevention of anaphylactic reactions, which would have been induced by multiple...

  9. Virus-Specific Antibody, in the Absence of T Cells, Mediates Demyelination in Mice Infected with a Neurotropic Coronavirus

    OpenAIRE

    Kim, Taeg S.; Perlman, Stanley

    2005-01-01

    Mice infected with mouse hepatitis virus strain JHM develop an inflammatory demyelinating disease in the central nervous system with many similarities to human multiple sclerosis. The mouse disease is primarily immune-mediated because demyelination is not detected in JHM-infected mice lacking T or B cells but does occur after transfer of JHM-specific T cells. Although less is known about the ability of antibodies to mediate demyelination, the presence of oligoclonally expanded B cells and hig...

  10. B cells assist allograft rejection in the deficiency of protein kinase c-theta.

    Science.gov (United States)

    Yan, Wenwei; Xu, Rui; Ma, Lian Li; Han, Wei; Geevarghese, Sunil K; Williams, Phillip E; Sciammas, Roger; Chong, Anita S; Yin, Deng Ping

    2013-09-01

    We have previously shown that mice deficient in protein kinase C theta (PKCθ) have the ability to reject cardiac allografts, but are susceptible to tolerance induction. Here we tested role of B cells in assisting alloimmune responses in the absence of PKCθ. Mouse cardiac allograft transplantations were performed from Balb/c (H-2d) to PKCθ knockout (PKCθ(-/-)), PKCθ and B cell double-knockout (PBDK, H-2b) mice and wild-type (WT) C57BL/6 (H-2b) mice. PBDK mice spontaneously accepted the allografts with the inhibition of NF-κB activation in the donor cardiac allograft. Anti-B cell antibody (rituximab) significantly delayed allograft rejection in PKCθ(-/-), but not in WT mice. Co-transfer of PKCθ(-/-) T plus PKCθ(-/-) B cells or primed sera triggered allograft rejection in Rag1(-/-) mice, and only major histocompatibility complex class II-enriched B cells, but not class I-enriched B cells, were able to promote rejection. This, together with the inability of PKCθ(-/-) and CD28(-/-) double-deficient (PCDK) mice to acutely reject allografts, suggested that an effective cognate interaction between PKCθ(-/-) T and B cells for acute rejection is CD28 molecule dependent. We conclude that T-B cell interactions synergize with PKCθ(-/-) T cells to mediate acute allograft rejection.

  11. Separation of effector cells mediating antibody-dependent cellular cytotoxicity (ADC) to erythrocyte targets from those mediating ADC to tumor targets.

    Science.gov (United States)

    Pollack, S B; Nelson, K; Grausz, J D

    1976-04-01

    Murine spleen cells mediate antibody-dependent cellular cytotoxicity (ADC) both to erythrocyte targets in a 51Cr release assay and to syngeneic tumor targets in a microcytotoxicity assay. The effector cells active in the two ADC assays can be separated by passage of the spleen cells through columns of Sephadex G-10 at 37 degrees C. Cells mediating ADC to sarcoma cells did not adhere to the G-10 and were recovered in the column effluent. These nonadherent cells were not cytotoxic to antibody-coated chicken red blood cells. Spleen cells which mediated ADC in a 51Cr release assay to the red cell targets adhered to G-10. Adherent effector cells could subsequently be recovered from the columns by elution with 5 X 10(-4) M EDTA. PMID:815438

  12. Mechanism of antibody-mediated viral clearance in immunotherapy of respiratory syncytial virus infection of cotton rats.

    OpenAIRE

    Prince, G A; Hemming, V G; Horswood, R L; Baron, P A; Murphy, B R; Chanock, R M

    1990-01-01

    Antibody-mediated clearance of respiratory syncytial virus from cotton rat pulmonary tissues occurs in the absence of complement and in the absence of the Fc portion of the immunoglobulin G molecule, suggesting that complement-independent, cell-independent neutralization is the major mechanism of clearance.

  13. A web-based pilot study of inter-pathologist reproducibility using the ISHLT 2004 working formulation for biopsy diagnosis of cardiac allograft rejection: the European experience

    DEFF Research Database (Denmark)

    Angelini, Annalisa; Andersen, Claus Boegelund; Bartoloni, Giovanni;

    2011-01-01

    The aim of this study was to assess, at the European level and using digital technology, the inter-pathologist reproducibility of the ISHLT 2004 system and to compare it with the 1990 system We also assessed the reproducibility of the morphologic criteria for diagnosis of antibody-mediated reject...

  14. Donor non-specific MICA antibodies in renal transplant recipients.

    Science.gov (United States)

    Sapák, Michal; Chreňová, Silvia; Tirpáková, Jana; Žilinská, Zuzana; Ďurmanová, Vladimíra; Shawkatová, Ivana; Jakuš, Vladimír; Kuba, Daniel; Buc, Milan

    2014-02-01

    Despite recent advances in solid organ transplantations, an antibody mediated rejection caused by donor specific antibodies is still a major problem in kidney graft survival. Besides HLA-induced humoral response, antibodies against MICA antigens have recently attracted attention because of their possible role in graft rejection. The aim of our study was to establish whether renal recipients produce antibodies against MICA molecules due to the transplantation and if they are specific for MICA antigens of the donors. MICA antibody screening was performed in 124 kidney recipient sera. 22 sera, that were found to be MICA antibody positive, were further examined for MICA antibody profiles and compared with donor MICA alleles. The analysis of MICA antibody positive sera showed mostly more complex reactivity patterns. A significant fraction of patient sera (59%) reacted not only with the donor MICA antigens, but also with other MICA patterns. A match between antibody specificities and MICA antigens was observed in 41% of renal recipients only. On the other hand, as much as in 36% of recipient sera were detected antibodies against their own MICA molecules. We did not prove a complete correlation between the recipient MICA antibody specificities and MICA antigens of the donor. We assume that MICA antibody induction occurs not only due to the allogeneic stimulation itself but also due to other factors that need to be elucidated.

  15. Heterosubtype neutralizing responses to influenza A (H5N1 viruses are mediated by antibodies to virus haemagglutinin.

    Directory of Open Access Journals (Sweden)

    Jean-Michel Garcia

    Full Text Available BACKGROUND: It is increasingly clear that influenza A infection induces cross-subtype neutralizing antibodies that may potentially confer protection against zoonotic infections. It is unclear whether this is mediated by antibodies to the neuraminidase (NA or haemagglutinin (HA. We use pseudoviral particles (H5pp coated with H5 haemagglutinin but not N1 neuraminidase to address this question. In this study, we investigate whether cross-neutralizing antibodies in persons unexposed to H5N1 is reactive to the H5 haemagglutinin. METHODOLOGY/PRINCIPAL FINDINGS: We measured H5-neutralization antibody titers pre- and post-vaccination using the H5N1 micro-neutralization test (MN and H5pp tests in subjects given seasonal vaccines and in selected sera from European elderly volunteers in a H5N1 vaccine trial who had detectable pre-vaccination H5N1 MN antibody titers. We found detectable (titer > or = 20 H5N1 neutralizing antibodies in a minority of pre-seasonal vaccine sera and evidence of a serological response to H5N1 in others after seasonal influenza vaccination. There was excellent correlation in the antibody titers between the H5N1 MN and H5pp tests. Similar correlations were found between MN and H5pp in the pre-vaccine sera from the cohort of H5N1 vaccine trial recipients. CONCLUSIONS/SIGNIFICANCE: Heterosubtype neutralizing antibody to H5N1 in healthy volunteers unexposed to H5N1 is mediated by cross-reaction to the H5 haemagglutinin.

  16. Daratumumab-mediated lysis of primary multiple myeloma cells is enhanced in combination with the human anti-KIR antibody IPH2102 and lenalidomide

    DEFF Research Database (Denmark)

    Nijhof, I. S.; Lammerts van Bueren, J. J.; van Kessel, B.;

    2015-01-01

    killer cell inhibitory receptors with the human monoclonal anti-KIR antibody IPH2102, next to activation of natural killer cells with the immune modulatory drug lenalidomide. In 4-hour antibody-dependent cell-mediated cytotoxicity assays, IPH2102 did not induce lysis of multiple myeloma cell lines...... effective treatment strategies can be designed for multiple myeloma by combining daratumumab with agents that independently modulate natural killer cell function.......Despite recent treatment improvements, multiple myeloma remains an incurable disease. Since antibody-dependent cell-mediated cytotoxicity is an important effector mechanism of daratumumab, we explored the possibility of improving daratumumab-mediated cell-mediated cytotoxicity by blocking natural...

  17. Recombinant antibody mediated delivery of organelle-specific DNA pH sensors along endocytic pathways

    Science.gov (United States)

    Modi, Souvik; Halder, Saheli; Nizak, Clément; Krishnan, Yamuna

    2013-12-01

    DNA has been used to build nanomachines with potential in cellulo and in vivo applications. However their different in cellulo applications are limited by the lack of generalizable strategies to deliver them to precise intracellular locations. Here we describe a new molecular design of DNA pH sensors with response times that are nearly 20 fold faster. Further, by changing the sequence of the pH sensitive domain of the DNA sensor, we have been able to tune their pH sensitive regimes and create a family of DNA sensors spanning ranges from pH 4 to 7.6. To enable a generalizable targeting methodology, this new sensor design also incorporates a `handle' domain. We have identified, using a phage display screen, a set of three recombinant antibodies (scFv) that bind sequence specifically to the handle domain. Sequence analysis of these antibodies revealed several conserved residues that mediate specific interactions with the cognate DNA duplex. We also found that all three scFvs clustered into different branches indicating that their specificity arises from mutations in key residues. When one of these scFvs is fused to a membrane protein (furin) that traffics via the cell surface, the scFv-furin chimera binds the `handle' and ferries a family of DNA pH sensors along the furin endocytic pathway. Post endocytosis, all DNA nanodevices retain their functionality in cellulo and provide spatiotemporal pH maps of retrogradely trafficking furin inside living cells. This new molecular technology of DNA-scFv-protein chimeras can be used to site-specifically complex DNA nanostructures for bioanalytical applications.DNA has been used to build nanomachines with potential in cellulo and in vivo applications. However their different in cellulo applications are limited by the lack of generalizable strategies to deliver them to precise intracellular locations. Here we describe a new molecular design of DNA pH sensors with response times that are nearly 20 fold faster. Further, by changing

  18. Antibody-Dependent Cell-Mediated Cytotoxicity to Hemagglutinin of Influenza A Viruses After Influenza Vaccination in Humans

    Science.gov (United States)

    Zhong, Weimin; Liu, Feng; Wilson, Jason R.; Holiday, Crystal; Li, Zhu-Nan; Bai, Yaohui; Tzeng, Wen-Pin; Stevens, James; York, Ian A.; Levine, Min Z.

    2016-01-01

    Background. Detection of neutralizing antibodies (nAbs) to influenza A virus hemagglutinin (HA) antigens by conventional serological assays is currently the main immune correlate of protection for influenza vaccines However, current prepandemic avian influenza vaccines are poorly immunogenic in inducing nAbs despite considerable protection conferred. Recent studies show that Ab-dependent cell-mediated cytotoxicity (ADCC) to HA antigens are readily detectable in the sera of healthy individuals and patients with influenza infection. Methods. Virus neutralization and ADCC activities of serum samples from individuals who received either seasonal or a stock-piled H5N1 avian influenza vaccine were evaluated by hemagglutination inhibition assay, microneutralization assay, and an improved ADCC natural killer (NK) cell activation assay. Results. Immunization with inactivated seasonal influenza vaccine led to strong expansion of both nAbs and ADCC-mediating antibodies (adccAbs) to H3 antigen of the vaccine virus in 24 postvaccination human sera. In sharp contrast, 18 individuals vaccinated with the adjuvanted H5N1 avian influenza vaccine mounted H5-specific antibodies with strong ADCC activities despite moderate virus neutralization capacity. Strength of HA-specific ADCC activities is largely associated with the titers of HA-binding antibodies and not with the fine antigenic specificity of anti-HA nAbs. Conclusions. Detection of both nAbs and adccAbs may better reflect protective capacity of HA-specific antibodies induced by avian influenza vaccines.

  19. Nitric oxide hinders antibody clearance from the surface of Trypanoplasma borreli and increases susceptibility to complement-mediated lysis.

    Science.gov (United States)

    Forlenza, Maria; Nakao, Miki; Wibowo, Indra; Joerink, Maaike; Arts, Joop A J; Savelkoul, Huub F J; Wiegertjes, Geert F

    2009-10-01

    Trypanoplasma borreli is an extracellular blood parasite of carp belonging to the same Order (Kinetoplastida) as African trypanosomes. These mammalian parasites have developed different strategies to evade the host immune system including antigenic variation, immunosuppression and clearance of surface-bound antibodies. The latter mechanism allows trypanosomes to use their swimming movement to cause surface-bound antibodies to 'sail' and accumulate at the posterior end of the parasite, to be internalized via the flagellar pocket and be degraded. There is no evidence that T. borreli shows antigenic variation, but during the late phases of infection NO-mediated immunosuppression is observed. High levels of nitric oxide (NO) lead to extensive tissue nitration whereas the parasite itself is not affected. Therefore, the induction of NO has thus far been considered a parasite-driven response with immunosuppressive effects. In the present study, we show that the induction of NO, particularly during the early phase of T. borreli infections, should be re-considered an effective part of the host immune response. We show that T. borreli rapidly removes surface-bound IgM. In addition, moderate concentrations of NO, by hindering surface antibody clearance, maintain high the concentrations of membrane-bound IgM, thereby favoring antibody-dependent complement-mediated parasite lysis. We performed a comprehensive quantitative gene expression analysis of in total seven different complement factors involved in all three activation pathways, differentiating between 1 and 4 isoforms for each complement gene. Our gene expression analysis supports an important role for antibody-dependent complement-mediated lysis of T. borreliin vivo. To our knowledge, NO-dependent inhibition of antibody clearance from the surface of kinetoplastid parasites has not been investigated. Our data support a role for NO as an important player in host-parasite interactions, not only as immune suppressor (late

  20. Anti-HIV-1 antibody-dependent cellular cytotoxicity mediated by hyperimmune bovine colostrum IgG.

    Science.gov (United States)

    Kramski, Marit; Lichtfuss, Gregor F; Navis, Marjon; Isitman, Gamze; Wren, Leia; Rawlin, Grant; Center, Rob J; Jaworowski, Anthony; Kent, Stephen J; Purcell, Damian F J

    2012-10-01

    Antibodies with antibody-dependent cellular cytotoxicity (ADCC) activity play an important role in protection against HIV-1 infection, but generating sufficient amounts of antibodies to study their protective efficacy is difficult. HIV-specific IgG can be easily and inexpensively produced in large quantities using bovine colostrum. We previously vaccinated cows with HIV-1 envelope gp140 and elicited high titers of anti-gp140-binding IgG in colostrum. In the present study, we determined whether bovine antibodies would also demonstrate specific cytotoxic activity. We found that bovine IgG bind to Fcγ-receptors (FcγRs) on human neutrophils, monocytes, and NK cells in a dose-dependent manner. Antibody-dependent killing was observed in the presence of anti-HIV-1 colostrum IgG but not nonimmune colostrum IgG. Killing was dependent on Fc and FcγR interaction since ADDC activity was not seen with F(ab')(2) fragments. ADCC activity was primarily mediated by CD14(+) monocytes with FcγRIIa (CD32a) as the major receptor responsible for monocyte-mediated ADCC in response to bovine IgG. In conclusion, we demonstrate that bovine anti-HIV colostrum IgG have robust HIV-1-specific ADCC activity and therefore offer a useful source of antibodies able to provide a rapid and potent response against HIV-1 infection. This could assist the development of novel Ab-mediated approaches for prevention of HIV-1 transmission. PMID:22730083

  1. Role of mobile passenger lymphocytes in the rejection of renal and cardiac allografts in the rat. A passenger lymphocyte-mediated graft-versus-host reaction amplifies the host response

    Energy Technology Data Exchange (ETDEWEB)

    van Vrieshilfgaarde, R.; Hermans, P.; Terpstra, J.L.; van Breda Viresman, P.J.

    1980-03-01

    It is demonstrated that passenger lymphocytes migrate out of rat renal allografts into host spleens in a radioresistant fashion. These mobile passenger lymphocytes within BN kidney and heart transplants are immunocompetent, since they elicit a graft-versus-host (GVH) reaction in the spleens of (LEW x BN)F2 hybrid hosts. The greater GVH reaction in (LEW x BN)F1 recipients of BN kidneys reflects the greater number of mobile passenger lymphocytes in the kidney when compared to the heart. The mobile passenger lymphocytes within BN renal allografts also cause a proliferative response in the spleens of the LEW hosts as well as an accelerated rejection of BN renal allografts when compared to BN cardiac allografts, for the differences between BN kidney and heart, both in terms of splenomegaly elicited in LEW as well as tempo of rejection, are abolished by total body x-irradiation of the donor with 900 rad. Results indicate that a mobile passenger lymphocyte mediated GVH reaction in the central lymphoid organs of the host augments the host response to allogenic kidneys and contributes materially to first-set renal allograft rejection; this GVH reaction on the other hand is not conspicuously present in LEW recipients of BN cardiac allografts and has therefore little effect on first-set cardiac allograft rejection.

  2. DISTURBANCE OF THE CARDIOMYOCYTE’S MACROMOLECULAR STRUCTURE IN HEART ALLOGRAFTS AS A SIGN OF CHRONIC REJECTION

    Directory of Open Access Journals (Sweden)

    A. G. Kupriyanova

    2012-01-01

    Full Text Available Chronic rejection, especially cardiac allograft vasculopathy, is a major limiting factor for long-term transplant survival. This process affects not only the blood vessels, but also cardiomyocytes. However, there are extremely few reports on the evaluation of their macromolecular structure state. The aim of the study was to evaluate the structural proteins of cardiomyocytes (actin, myosin, troponin I, titin, desmin, vinculin of heart allografts in different periods after the operation (from 6 days to 15 years. Major changes of macromolecular structure were revealed in late period after transplantation (6 months – 15 years. The contribution of humoral immune response in the process of chronic cardiac allograft rejection was observed: in eight of twelve recipients episodes of acute humoral rejection had been repeatedly registered; disorders of the expression of 5 proteins out of 6 characterized were found in recipients with recurrent and persistent antibody-mediated rejection

  3. Cefditoren and ceftriaxone enhance complement-mediated immunity in the presence of specific antibodies against antibiotic-resistant pneumococcal strains.

    Directory of Open Access Journals (Sweden)

    Elisa Ramos-Sevillano

    Full Text Available BACKGROUND: Specific antibodies mediate humoral and cellular protection against invading pathogens such as Streptococcus pneumoniae by activating complement mediated immunity, promoting phagocytosis and stimulating bacterial clearance. The emergence of pneumococcal strains with high levels of antibiotic resistance is of great concern worldwide and a serious threat for public health. METHODOLOGY/PRINCIPAL FINDINGS: Flow cytometry was used to determine whether complement-mediated immunity against three antibiotic-resistant S. pneumoniae clinical isolates is enhanced in the presence of sub-inhibitory concentrations of cefditoren and ceftriaxone. The binding of acute phase proteins such as C-reactive protein and serum amyloid P component, and of complement component C1q, to pneumococci was enhanced in the presence of serum plus either of these antibiotics. Both antibiotics therefore trigger the activation of the classical complement pathway against S. pneumoniae. C3b deposition was also increased in the presence of specific anti-pneumococcal antibodies and sub-inhibitory concentrations of cefditoren and ceftriaxone confirming that the presence of these antibiotics enhances complement-mediated immunity to S. pneumoniae. CONCLUSIONS/SIGNIFICANCE: Using cefditoren and ceftriaxone to promote the binding of acute phase proteins and C1q to pneumococci, and to increase C3b deposition, when anti-pneumococcal antibodies are present, might help reduce the impact of antibiotic resistance in S. pneumoniae infections.

  4. Heterosexual Rejection and Mate Choice: A Sociometer Perspective.

    Science.gov (United States)

    Zhang, Lin; Liu, Shen; Li, Yue; Ruan, Lu-Jun

    2015-01-01

    Previous studies about the effects of social rejection on individuals' social behaviors have produced mixed results and tend to study mating behaviors from a static point of view. However, mate selection in essence is a dynamic process, and therefore sociometer theory opens up a new perspective for studying mating and its underlying practices. Based on this theory and using self-perceived mate value in the relationship between heterosexual rejection and mate choice as a mediating role, this current study examined the effects of heterosexual rejection on mate choice in two experiments. Results showed that heterosexual rejection significantly reduced self-perceived mate value, expectation, and behavioral tendencies, while heterosexual acceptance indistinctively increased these measures. Self-perceived mate value did not serve as a mediator in the relationship between heterosexual rejection and mate expectation, but it mediated the relationship between heterosexual rejection and mating behavior tendencies toward potential objects. Moreover, individuals evaded both rejection and irrelevant people when suffering from rejection.

  5. Development of IgG Mediated Antibody Dependent Cell-mediated Cytotoxicity (ADCC) in the Serum and Genital Mucosa of HIV Seroconverters

    OpenAIRE

    Aziz, Mariam; Mahmood, Fareeha; Mata, Mariana; Durkin, Helen G.; Liu, Chenglong; Greenblatt, Ruth M.; Nowicki, Marek; Elizabeth T Golub; Anastos, Kathryn; French, Audrey L.; Baum, Linda L.

    2015-01-01

    Background We measured antibody-dependent cell mediated cytotoxicity (ADCC) activity in serum and genital fluids of heterosexually exposed women during HIV seroconversion. Methods Plasma and cervico-vaginal lavage (CVL) fluid from 11 seroconverters (SC) were analyzed biannually from one year pre- to 6 year post-seroconversion using a 51Cr-release assay to measure HIV-1 gp120 specific ADCC. Results No SC had significant HIV specific CVL ADCC activity before seroconversion or until 1.5 yr after...

  6. Clinical Cancer Therapy by NK Cells via Antibody-Dependent Cell-Mediated Cytotoxicity

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    Kory L. Alderson

    2011-01-01

    Full Text Available Natural killer (NK cells are powerful effector cells that can be directed to eliminate tumor cells through tumor-targeted monoclonal antibodies (mAbs. Some tumor-targeted mAbs have been successfully applied in the clinic and are included in the standard of care for certain malignancies. Strategies to augment the antitumor response by NK cells have led to an increased understanding of how to improve their effector responses. Next-generation reagents, such as molecularly modified mAbs and mAb-cytokine fusion proteins (immunocytokines, ICs designed to augment NK-mediated killing, are showing promise in preclinical and some clinical settings. Continued research into the antitumor effects induced by NK cells and tumor-targeted mAbs suggests that additional intrinsic and extrinsic factors may influence the antitumor response. Therefore more research is needed that focuses on evaluating which NK cell and tumor criteria are best predictive of a clinical response and which combination immunotherapy regimens to pursue for distinct clinical settings.

  7. Antibody- and cell-mediated immune responses of Actinobacillus pleuropneumoniae-infected and bacterin-vaccinated pigs.

    Science.gov (United States)

    Furesz, S E; Mallard, B A; Bossé, J T; Rosendal, S; Wilkie, B N; MacInnes, J I

    1997-01-01

    Current porcine pleuropneumonia bacterins afford only partial protection by decreasing mortality but not morbidity. In order to better understand the type(s) of immune response associated with protection, antibody- and cell-mediated immune responses (CMIR) were compared for piglets before and after administration of a commercial bacterin, which confers partial protection, or a low-dose (10(5) CFU/ml) aerosol challenge with Actinobacillus pleuropneumoniae CM5 (LD), which induces complete protection. Control groups received phosphate-buffered saline or adjuvant. Serum antibody response, antibody avidity, delayed-type hypersensitivity (DTH), and lymphocyte blastogenic responses were measured and compared among treatment groups to the lipopolysaccharide (LPS), capsular polysaccharide (CPS), hemolysin (HLY), and outer membrane proteins (OMP) of A. pleuropneumoniae. Peripheral blood lymphocytes and sera were collected prior to and following primary and secondary immunization-infection and high-dose A. pleuropneumoniae CM5 (10(7) CFU/ml) aerosol challenge. Serum antibody and DTH, particularly that to HLY, differed significantly between treatment groups, and increases were associated with protection. LD-infected piglets had higher antibody responses (P < or = 0.01) and antibody avidity (P < or = 0.10) than bacterin-vaccinated and control groups. Anti-HLY antibodies were consistently associated with protection, whereas anti-LPS and anti-CPS antibodies were not. LD-infected animals had higher DTH responses, particularly to HLY, than bacterin-vaccinated pigs (P < or = 0.03). The LD-infected group maintained consistent blastogenic responses to HLY, LPS, CPS, and OMP over the course of infection, unlike the bacterin-vaccinated and control animals. These data suggest that the immune responses induced by a commercial bacterin are very different from those induced by LD aerosol infection and that current bacterins may be modified, for instance, by addition of HLY, so as to

  8. Osthole prevents anti-Fas antibody-induced hepatitis in mice by affecting the caspase-3-mediated apoptotic pathway.

    Science.gov (United States)

    Okamoto, Toshihiro; Kawasaki, Toru; Hino, Okio

    2003-02-15

    Fas (Apo-1/CD95) ligand, which is a type II membrane protein, is a major inducer of apoptosis. Osthole is a coumarin derivative present in medicinal plants. The effect of osthole on hepatitis induced by anti-Fas antibody in mice was studied. Pretreatment of mice with osthole (10, 50, and 100 mg/kg, i.p.) prevented the elevation of plasma alanine aminotransferase (ALT) caused by anti-Fas antibody (175 microg/kg, i.v.). Administration of osthole to mice even at a dose of 10 mg/kg significantly inhibited of anti-Fas antibody-induced elevation of plasma ALT. Capase-3 is a cysteine protease, and treatment of mice with anti-Fas antibody caused an elevation of caspase-3 activity at 3.5 and 6 hr. Pretreatment of mice with osthole (100 mg/kg, i.p.) inhibited the elevation of caspase-3 activity caused by anti-Fas antibody. However, the addition of osthole (up to 10(-4)M) to a liver cytosol fraction isolated from mice treated with anti-Fas antibody did not inhibit caspase-3 activity in vitro. Thus, treatment of mice with osthole inhibited caspase-3 activity by an effect upstream of caspase-3 activation. The livers of mice treated with anti-Fas antibody contained apoptotic and dead cells; osthole attenuated the development of this apoptosis and cell death. The present results show that osthole prevented anti-Fas antibody-induced hepatitis by inhibiting the Fas-mediated apoptotic pathway. PMID:12566097

  9. Interplay between immune responses to HLA and non-HLA self-antigens in allograft rejection.

    Science.gov (United States)

    Angaswamy, Nataraju; Tiriveedhi, Venkataswarup; Sarma, Nayan J; Subramanian, Vijay; Klein, Christina; Wellen, Jason; Shenoy, Surendra; Chapman, William C; Mohanakumar, T

    2013-11-01

    Recent studies strongly suggest an increasing role for immune responses against self-antigens (Ags) which are not encoded by the major histocompatibility complex in the immunopathogenesis of allograft rejection. Although, improved surgical techniques coupled with improved methods to detect and avoid sensitization against donor human leukocyte antigen (HLA) have improved the immediate and short term function of transplanted organs. However, acute and chronic rejection still remains a vexing problem for the long term function of the transplanted organ. Immediately following organ transplantation, several factors both immune and non immune mechanisms lead to the development of local inflammatory milieu which sets the stage for allograft rejection. Traditionally, development of antibodies (Abs) against mismatched donor HLA have been implicated in the development of Ab mediated rejection. However, recent studies from our laboratory and others have demonstrated that development of humoral and cellular immune responses against non-HLA self-Ags may contribute in the pathogenesis of allograft rejection. There are reports demonstrating that immune responses to self-Ags especially Abs to the self-Ags as well as cellular immune responses especially through IL17 has significant pro-fibrotic properties leading to chronic allograft failure. This review summarizes recent studies demonstrating the role for immune responses to self-Ags in allograft immunity leading to rejection as well as present recent evidence suggesting there is interplay between allo- and autoimmunity leading to allograft dysfunction.

  10. Conformational Masking and Receptor-Dependent Unmasking of Highly Conserved Env Epitopes Recognized by Non-Neutralizing Antibodies That Mediate Potent ADCC against HIV-1.

    Science.gov (United States)

    Lewis, George K; Finzi, Andrés; DeVico, Anthony L; Pazgier, Marzena

    2015-09-01

    The mechanism of antibody-mediated protection is a major focus of HIV-1 vaccine development and a significant issue in the control of viremia. Virus neutralization, Fc-mediated effector function, or both, are major mechanisms of antibody-mediated protection against HIV-1, although other mechanisms, such as virus aggregation, are known. The interplay between virus neutralization and Fc-mediated effector function in protection against HIV-1 is complex and only partially understood. Passive immunization studies using potent broadly neutralizing antibodies (bnAbs) show that both neutralization and Fc-mediated effector function provides the widest dynamic range of protection; however, a vaccine to elicit these responses remains elusive. By contrast, active immunization studies in both humans and non-human primates using HIV-1 vaccine candidates suggest that weakly neutralizing or non-neutralizing antibodies can protect by Fc-mediated effector function, albeit with a much lower dynamic range seen for passive immunization with bnAbs. HIV-1 has evolved mechanisms to evade each type of antibody-mediated protection that must be countered by a successful AIDS vaccine. Overcoming the hurdles required to elicit bnAbs has become a major focus of HIV-1 vaccine development. Here, we discuss a less studied problem, the structural basis of protection (and its evasion) by antibodies that protect only by potent Fc-mediated effector function. PMID:26393642

  11. LGR5 expressing cells of hair follicle as potential targets for antibody mediated anti-cancer laser therapy

    Science.gov (United States)

    Popov, Boris V.

    2013-02-01

    Near infrared laser immunotherapy becomes now a new promising research field to cure the patients with cancers. One of the critical limitation in medical application of this treatment is availability of the specific markers for delivery of laser-sensitive nanoparticles. When coupled to antibodies to the cancer stem cells markers these nanoparticles may be delivered to the cancer tissue and mediate the laser induced thermolysis of the cancer stem cells that initiate and drive growth of cancer. This paper addresses the Lgr5 cell surface marker mediating the Wnt/β-catenin signal transduction as a potential target for anti-cancer laser immunotherapy of skin cancers.

  12. Enhanced killing of chordoma cells by antibody-dependent cell-mediated cytotoxicity employing the novel anti-PD-L1 antibody avelumab.

    Science.gov (United States)

    Fujii, Rika; Friedman, Eitan R; Richards, Jacob; Tsang, Kwong Y; Heery, Christopher R; Schlom, Jeffrey; Hodge, James W

    2016-06-01

    Chordoma, a rare bone tumor derived from the notochord, has been shown to be resistant to conventional therapies. Checkpoint inhibition has shown great promise in immune-mediated therapy of diverse cancers. The anti-PD-L1 mAb avelumab is unique among checkpoint inhibitors in that it is a fully human IgG1 capable of mediating antibody-dependent cell-mediated cytotoxicity (ADCC) of PD-L1-expressing tumor cells. Here, we investigated avelumab as a potential therapy for chordoma. We examined 4 chordoma cell lines, first for expression of PD-L1, and in vitro for ADCC killing using NK cells and avelumab. PD-L1 expression was markedly upregulated by IFN-γ in all 4 chordoma cell lines, which significantly increased sensitivity to ADCC. Brachyury is a transcription factor that is uniformly expressed in chordoma. Clinical trials are ongoing in which chordoma patients are treated with brachyury-specific vaccines. Co-incubating chordoma cells with brachyury-specific CD8+ T cells resulted in significant upregulation of PD-L1 on the tumor cells, mediated by the CD8+ T cells' IFN-γ production, and increased sensitivity of chordoma cells to avelumab-mediated ADCC. Residential cancer stem cell subpopulations of chordoma cells were also killed by avelumab-mediated ADCC to the same degree as non-cancer stem cell populations. These findings suggest that as a monotherapy for chordoma, avelumab may enable endogenous NK cells, while in combination with T-cell immunotherapy, such as a vaccine, avelumab may enhance NK-cell killing of chordoma cells via ADCC.

  13. Participation of functionally active plasma cells in acute rejection and response to therapy in renal allografts.

    Science.gov (United States)

    Bhat, Zeenat Yousuf; Bostwick, David G; Hossain, Deloar; Zeng, Xu

    2014-07-01

    Acute rejection (AR) includes T-cell-mediated and antibody-mediated rejection. The inflammatory infiltrate comprised not only T cells but also varying amounts of B cells (CD20(+)) and plasma cells (CD138(+)). The latter are associated with poor clinical outcomes, but their functional status is not clear. The phosphorylation of the S6 ribosomal protein (p-S6RP) is present in cells that are metabolically active, thus identifying functionally active antibody-secreting plasma cells. This study was designed to evaluate the clinical significance of functionally active p-S6RP plasma cells in AR in renal allografts. Renal allografts with biopsy evidence of AR during 2006-2009 were included. Immunohistochemistry staining for CD20, CD138, and p-S6RP was performed on paraffin-embedded slides and scaled as 0-6. The response to antirejection treatment was assessed by the serum creatinine ratio (CrR) at rejection episode (time 0) and following treatment (4 and 12 weeks). Patients with lower scores (0-2) were compared with a higher scored group (3-6). The T-test was conducted using statistical significance of p<0.05. A total of 28 patients (40.7 ± 14.3 year; M:F=15:13) were diagnosed with acute T-cell-mediated rejection (I and II). The p-S6RP staining in the high-score group had a significantly higher CrR (p<0.05) than the low-score group at the time of biopsy, 4 and 12 weeks following treatment. There was no significant difference in the CrR between groups for CD20 or CD138 staining. Functional antibody-secreting p-S6RP plasma cells are actively participating in AR and associated with poor response to treatment in renal allografts. PMID:24684655

  14. The Biological Effects of IL-21 Signaling on B-Cell-Mediated Responses in Organ Transplantation

    Science.gov (United States)

    Wu, Yongkang; van Besouw, Nicole M.; Shi, Yunying; Hoogduijn, Martin J.; Wang, Lanlan; Baan, Carla C.

    2016-01-01

    Antibody-mediated rejection has emerged as one of the major issues limiting the success of organ transplantation. It exerts a highly negative impact on graft function and outcome, and effective treatment is lacking. The triggers for antibody development, and the mechanisms leading to graft dysfunction and failure, are incompletely understood. The production of antibodies is dependent on instructions from various immunocytes including CD4 T-helper cells that secrete interleukin (IL)-21 and interact with antigen-specific B-cells via costimulatory molecules. In this article, we discuss the role of IL-21 in the activation and differentiation of B-cells and consider the mechanisms of IL-21 and B-cell interaction. An improved understanding of the biological mechanisms involved in antibody-mediated complications after organ transplantation could lead to the development of novel therapeutic strategies, which control humoral alloreactivity, potentially preventing and treating graft-threatening antibody-mediated rejection. PMID:27602031

  15. The Biological Effects of IL-21 Signaling on B-Cell-Mediated Responses in Organ Transplantation.

    Science.gov (United States)

    Wu, Yongkang; van Besouw, Nicole M; Shi, Yunying; Hoogduijn, Martin J; Wang, Lanlan; Baan, Carla C

    2016-01-01

    Antibody-mediated rejection has emerged as one of the major issues limiting the success of organ transplantation. It exerts a highly negative impact on graft function and outcome, and effective treatment is lacking. The triggers for antibody development, and the mechanisms leading to graft dysfunction and failure, are incompletely understood. The production of antibodies is dependent on instructions from various immunocytes including CD4 T-helper cells that secrete interleukin (IL)-21 and interact with antigen-specific B-cells via costimulatory molecules. In this article, we discuss the role of IL-21 in the activation and differentiation of B-cells and consider the mechanisms of IL-21 and B-cell interaction. An improved understanding of the biological mechanisms involved in antibody-mediated complications after organ transplantation could lead to the development of novel therapeutic strategies, which control humoral alloreactivity, potentially preventing and treating graft-threatening antibody-mediated rejection. PMID:27602031

  16. DNA-mediated strand displacement facilitates sensitive electronic detection of antibodies in human serums.

    Science.gov (United States)

    Dou, Baoting; Yang, Jianmei; Shi, Kai; Yuan, Ruo; Xiang, Yun

    2016-09-15

    We describe here the development of a sensitive and convenient electronic sensor for the detection of antibodies in human serums. The sensor is constructed by self-assembly formation of a mixed monolayer containing the small molecule epitope conjugated double stranded DNA probes on gold electrode. The target antibody binds the epitope on the dsDNA probe and lowers the melting temperature of the duplex, which facilitates the displacement of the antibody-linked strand of the duplex probe by an invading methylene blue-tagged single stranded DNA (MB-ssDNA) through the strand displacement reaction and leads to the capture of many MB-ssDNA on the sensor surface. Subsequent electrochemical oxidation of the methylene blue labels results in amplified current response for sensitive monitoring of the antibodies. The antibody assay conditions are optimized and the sensor exhibits a linear range between 1.0 and 25.0nM with a detection limit of 0.67nM for the target antibody. The sensor is also selective and can be employed to detect the target antibodies in human serum samples. With the advantages of using small molecule epitope as the antibody recognition element over traditional antigen, the versatile manipulability of the DNA probes and the unique properties of the electrochemical transduction technique, the developed sensor thus hold great potential for simple and sensitive detection of different antibodies and other proteins in real samples. PMID:27111124

  17. Influence of IgG Subclass on Human Antimannan Antibody-Mediated Resistance to Hematogenously Disseminated Candidiasis in Mice.

    Science.gov (United States)

    Nishiya, Casey T; Boxx, Gayle M; Robison, Kerry; Itatani, Carol; Kozel, Thomas R; Zhang, Mason X

    2015-11-16

    Candida albicans is a yeast-like pathogen and can cause life-threatening systemic candidiasis. Its cell surface is enriched with mannan that is resistant to complement activation. Previously, we developed the recombinant human IgG1 antimannan antibody M1g1. M1g1 was found to promote complement activation and phagocytosis and protect mice from systemic candidiasis. Here, we evaluate the influence of IgG subclass on antimannan antibody-mediated protection. Three IgG subclass variants of M1g1 were constructed: M1g2, M1g3, and M1g4. The IgG subclass identity for each variant was confirmed with DNA sequence and subclass-specific antibodies. These variants contain identical M1 Fabs and exhibited similar binding affinities for C. albicans yeast and purified mannan. Yeast cells and hyphae recovered from the kidney of antibody-treated mice with systemic candidiasis showed uniform binding of each variant, indicating constitutive expression of the M1 epitope and antibody opsonization in the kidney. All variants promoted deposition of both murine and human C3 onto the yeast cell surface, with M1g4 showing delayed activation, as determined by flow cytometry and immunofluorescence microscopy. M1g4-mediated complement activation was found to be associated with its M1 Fab that activates the alternative pathway in an Fc-independent manner. Treatment with each subclass variant extended the survival of mice with systemic candidiasis (P candidiasis is influenced by its IgG subclass.

  18. Antibody-Dependent Cell-Mediated Cytotoxicity to Hemagglutinin of Influenza A Viruses After Influenza Vaccination in Humans.

    Science.gov (United States)

    Zhong, Weimin; Liu, Feng; Wilson, Jason R; Holiday, Crystal; Li, Zhu-Nan; Bai, Yaohui; Tzeng, Wen-Pin; Stevens, James; York, Ian A; Levine, Min Z

    2016-04-01

    Background.  Detection of neutralizing antibodies (nAbs) to influenza A virus hemagglutinin (HA) antigens by conventional serological assays is currently the main immune correlate of protection for influenza vaccines However, current prepandemic avian influenza vaccines are poorly immunogenic in inducing nAbs despite considerable protection conferred. Recent studies show that Ab-dependent cell-mediated cytotoxicity (ADCC) to HA antigens are readily detectable in the sera of healthy individuals and patients with influenza infection. Methods.  Virus neutralization and ADCC activities of serum samples from individuals who received either seasonal or a stock-piled H5N1 avian influenza vaccine were evaluated by hemagglutination inhibition assay, microneutralization assay, and an improved ADCC natural killer (NK) cell activation assay. Results.  Immunization with inactivated seasonal influenza vaccine led to strong expansion of both nAbs and ADCC-mediating antibodies (adccAbs) to H3 antigen of the vaccine virus in 24 postvaccination human sera. In sharp contrast, 18 individuals vaccinated with the adjuvanted H5N1 avian influenza vaccine mounted H5-specific antibodies with strong ADCC activities despite moderate virus neutralization capacity. Strength of HA-specific ADCC activities is largely associated with the titers of HA-binding antibodies and not with the fine antigenic specificity of anti-HA nAbs. Conclusions.  Detection of both nAbs and adccAbs may better reflect protective capacity of HA-specific antibodies induced by avian influenza vaccines. PMID:27419174

  19. X-linked inhibitor of apoptosis protein mediates tumor cell resistance to antibody-dependent cellular cytotoxicity.

    Science.gov (United States)

    Evans, M K; Sauer, S J; Nath, S; Robinson, T J; Morse, M A; Devi, G R

    2016-01-01

    Inflammatory breast cancer (IBC) is the deadliest, distinct subtype of breast cancer. High expression of epidermal growth factor receptors [EGFR or human epidermal growth factor receptor 2 (HER2)] in IBC tumors has prompted trials of anti-EGFR/HER2 monoclonal antibodies to inhibit oncogenic signaling; however, de novo and acquired therapeutic resistance is common. Another critical function of these antibodies is to mediate antibody-dependent cellular cytotoxicity (ADCC), which enables immune effector cells to engage tumors and deliver granzymes, activating executioner caspases. We hypothesized that high expression of anti-apoptotic molecules in tumors would render them resistant to ADCC. Herein, we demonstrate that the most potent caspase inhibitor, X-linked inhibitor of apoptosis protein (XIAP), overexpressed in IBC, drives resistance to ADCC mediated by cetuximab (anti-EGFR) and trastuzumab (anti-HER2). Overexpression of XIAP in parental IBC cell lines enhances resistance to ADCC; conversely, targeted downregulation of XIAP in ADCC-resistant IBC cells renders them sensitive. As hypothesized, this ADCC resistance is in part a result of the ability of XIAP to inhibit caspase activity; however, we also unexpectedly found that resistance was dependent on XIAP-mediated, caspase-independent suppression of reactive oxygen species (ROS) accumulation, which otherwise occurs during ADCC. Transcriptome analysis supported these observations by revealing modulation of genes involved in immunosuppression and oxidative stress response in XIAP-overexpressing, ADCC-resistant cells. We conclude that XIAP is a critical modulator of ADCC responsiveness, operating through both caspase-dependent and -independent mechanisms. These results suggest that strategies targeting the effects of XIAP on caspase activation and ROS suppression have the potential to enhance the activity of monoclonal antibody-based immunotherapy. PMID:26821068

  20. C-C chemokine receptor-7 mediated endocytosis of antibody cargoes into intact cells

    Directory of Open Access Journals (Sweden)

    Xavier eCharest-Morin

    2013-09-01

    Full Text Available The C-C chemokine receptor-7 (CCR7 is a G protein coupled receptor that has a role in leukocyte homing, but that is also expressed in aggressive tumor cells. Preclinical research supports that CCR7 is a valid target in oncology. In view of the increasing availability of therapeutic monoclonal antibodies that carry cytotoxic cargoes, we studied the feasibility of forcing intact cells to internalize known monoclonal antibodies by exploiting the cycle of endocytosis and recycling triggered by the CCR7 agonist CCL19. Firstly, an anti-CCR7 antibody (CD197; clone 150503 labeled surface recombinant CCR7 expressed in intact HEK 293a cells and the fluorescent antibody was internalized following CCL19 treatment. Secondly, a recombinant myc-tagged CCL19 construction was exploited along the anti-myc monoclonal antibody 4A6. The myc-tagged ligand was produced as a conditioned medium of transfected HEK 293a cells that contained the equivalent of 430 ng/ml of immunoreactive CCL19 (average value, ELISA determination. CCL19-myc, but not authentic CCL19, carried the fluorophore-labeled antibody 4A6 into other recipient cells that expressed recombinant CCR7 (microscopy, cytofluorometry. The immune complexes were apparent in endosomal structures, colocalized well with the small GTPase Rab5 and progressed toward Rab7-positive endosomes. A dominant negative form of Rab5 (GDP-locked inhibited this endocytosis. Further, endosomes in CCL19-myc- or CCL19-stimulated cells were positive for β-arrestin2, but rarely for β-arrestin1. Following treatment with CCL19-myc and the 4A6 antibody, the melanoma cell line A375 that expresses endogenous CCR7 was specifically stained using a secondary peroxidase-conjugated antibody. Agonist-stimulated CCR7 can transport antibody-based cargoes, with possible therapeutic applications in oncology.

  1. Bispecific Antibodies that Mediate Killing of Cells Infected with Human Immunodeficiency Virus of Any Strain

    Science.gov (United States)

    Berg, Jorg; Lotscher, Erika; Steimer, Kathelyn S.; Capon, Daniel J.; Baenziger, Jurg; Jack, Hans-Martin; Wabl, Matthias

    1991-06-01

    Although AIDS patients lose human immunodeficiency virus (HIV)-specific cytotoxic T cells, their remaining CD8-positive T lymphocytes maintain cytotoxic function. To exploit this fact we have constructed bispecific antibodies that direct cytotoxic T lymphocytes of any specificity to cells that express gp120 of HIV. These bispecific antibodies comprise one heavy/light chain pair from an antibody to CD3, linked to a heavy chain whose variable region has been replaced with sequences from CD4 plus a second light chain. CD3 is part of the antigen receptor on T cells and is responsible for signal transduction. In the presence of these bispecific antibodies, T cells of irrelevant specificity effectively lyse HIV-infected cells in vitro.

  2. AAVrh.10-Mediated Expression of an Anti-Cocaine Antibody Mediates Persistent Passive Immunization That Suppresses Cocaine-Induced Behavior

    OpenAIRE

    Rosenberg, Jonathan B; Hicks, Martin J.; De, Bishnu P.; Pagovich, Odelya; Frenk, Esther; Kim D. Janda; Wee, Sunmee; Koob, George F.; Hackett, Neil R.; KaMinSky, Stephen M.; Worgall, Stefan; Tignor, Nicole; Mezey, Jason G; Crystal, Ronald G.

    2012-01-01

    Cocaine addiction is a major problem affecting all societal and economic classes for which there is no effective therapy. We hypothesized an effective anti-cocaine vaccine could be developed by using an adeno-associated virus (AAV) gene transfer vector as the delivery vehicle to persistently express an anti-cocaine monoclonal antibody in vivo, which would sequester cocaine in the blood, preventing access to cognate receptors in the brain. To accomplish this, we constructed AAVrh.10antiCoc.Mab...

  3. The Natural History of Biopsy-Negative Rejection after Heart Transplantation

    Directory of Open Access Journals (Sweden)

    Zhaoyi Tang

    2013-01-01

    Full Text Available Purpose. The most recent International Society for Heart and Lung Transplantation (ISHLT biopsy scale classifies cellular and antibody-mediated rejections. However, there are cases with acute decline in left ventricular ejection fraction (LVEF ≤ 45% but no evidence of rejection on biopsy. Characteristics and treatment response of this biopsy negative rejection (BNR have yet to be elucidated. Methods. Between 2002 and 2012, we found 12 cases of BNR in 11 heart transplant patients as previously defined. One of the 11 patients was treated a second time for BNR. Characteristics and response to treatment were noted. Results. 12 cases (of 11 patients were reviewed and 11 occurred during the first year after transplant. 8 cases without heart failure symptoms were treated with an oral corticosteroids bolus and taper or intravenous immunoglobulin. Four cases with heart failure symptoms were treated with thymoglobulin, intravenous immunoglobulin, and intravenous methylprednisolone followed by an oral corticosteroids bolus and taper. Overall, 7 cases resulted in return to normal left ventricular function within a mean of 14 ± 10 days from the initial biopsy. Conclusion. BNR includes cardiac dysfunction and can be a severe form of rejection. Characteristics of these cases of rejection are described with most cases responding to appropriate therapy.

  4. Vascularized composite allotransplantation: current standards and novel approaches to prevent acute rejection and chronic allograft deterioration.

    Science.gov (United States)

    Kueckelhaus, Maximilian; Fischer, Sebastian; Seyda, Midas; Bueno, Ericka M; Aycart, Mario A; Alhefzi, Muayyad; ElKhal, Abdallah; Pomahac, Bohdan; Tullius, Stefan G

    2016-06-01

    The advent of more potent immunosuppressants led to the first successful human upper extremity transplantation in 1998. At this time, >100 upper extremity transplants, 30 face transplants, and a variety of other vascularized composite allotransplantation (VCA) procedures have been performed around the world. VCA recipients present unique challenges for transplantation. The incidence of acute rejection exceeds 80% in hand and face transplantation and is well documented, whereas reports about antibody-mediated rejection and chronic rejection remain scarce. Immunosuppression protocols commonly used at US centers are derived from solid organ transplantation protocols. Novel approaches to minimize rejections in VCA may include improved HLA matching and considerations toward cytomegalovirus infection status. New graft preservation techniques may decrease immunogenicity prior to transplant. Novel monitoring methods such as valid biomarkers, ultrasound biomicroscopy, and sentinel flaps may enable earlier diagnosis of rejection. Cell-based therapies are being explored to achieve immunosuppressive regimen minimization or even tolerance induction. The efficacy of local immunosuppression in clinical VCA remains controversial. In conclusion, although immunosuppressive strategies adapted from SOT have demonstrated good midterm results, focusing on the unique features of VCA grafts may enable additional, more specific treatment strategies in the future and improved long-term graft outcomes. PMID:26265179

  5. Protein Delivery of Thymidylate Kinase Mediated by Tumor-Specific Antibody-Precoated Microvesicles.

    Science.gov (United States)

    Mohammadzadeh-Vardin, Mohammad; Panahpour, Hamdollah; Golmohammadi, Mohammad Ghasem; Sagha, Mohsen

    2016-01-01

    Molecular targeted therapy is an important, novel approach in the treatment of cancer because it interferes with certain molecules involved in carcinogenesis and tumor growth. Examples include monoclonal antibodies, microvesicles, and suicide genes. Several studies have focused on targeted therapies in prostate cancer, which is a serious cause of cancer death in men. We hypothesize that antibody-coated microvesicles can deliver thymidylate kinase, a suicide protein, to prostate cancer cells, potentiating them to death following azidothymidine (AZT) treatment. PMID:27278881

  6. Anti-Glycine Receptor Antibody Mediated Progressive Encephalomyelitis with Rigidity and Myoclonus Associated with Breast Cancer

    Directory of Open Access Journals (Sweden)

    Sofie N. De Blauwe

    2013-01-01

    Full Text Available We describe a 66-year-old woman who presented with a dramatic course of PERM. Anti-glycine receptor antibodies were found. She stabilized after plasma-exchange and partly recovered. Eighteen months later, a diagnosis of smouldering breast cancer with bone marrow metastasis was made. There are indications that this tumor was already present at first presentation. An overview of PERM and anti-glycine receptor antibodies is given.

  7. Spontaneous rupture of atrioventricular valve tensor apparatus as late manifestation of anti-Ro/SSA antibody-mediated cardiac disease.

    Science.gov (United States)

    Cuneo, Bettina F; Fruitman, Deborah; Benson, D Woodrow; Ngan, Bo-Yee; Liske, Michael R; Wahren-Herlineus, Marie; Ho, S Yen; Jaeggi, Edgar

    2011-03-01

    Atrioventricular (AV) block and endocardial fibroelastosis associated with dilated cardiomyopathy are the most common clinical manifestations of anti-Ro/SSA-mediated fetal cardiac disease. Valvar dysfunction has not been a prominent feature of this disease; however, recent anecdotal cases have suggested an association between rupture of the AV valve tensor apparatus and maternal anti-Ro/SSA antibodies. In the present study, we have described the clinical and laboratory findings and reviewed the published data for infants of anti-Ro/SSA-positive pregnancies with AV valve insufficiency due to chordal rupture from the papillary muscles. The histopathologic features of the papillary muscle and ventricular free wall and septum biopsy specimens were examined and compared to the sections of AV leaflets from 6 autopsied fetuses with anti-Ro/SSA-mediated complete AV block without chordal disruption. Specific epitopes to the p200 region of Ro52, and Ro60 antibodies were evaluated in cases with chordal rupture. Severe AV valve insufficiency was detected prenatally (as early as 34 weeks of gestation) or postnatally (as late as 182 days) after areas of patchy echogenicity were noted in the papillary muscle at 19 to 22 weeks of gestation. Postnatally, urgent valve surgery was performed in 5 of 6 patients; 1 of 6 patients died preoperatively. All patients tested positive for Ro52. Valve leaflet tissue from the autopsy specimens was normal. The ventricular free wall and septum biopsy specimens from a patient with chordal rupture showed normal tissue; however, the papillary muscle biopsy specimens demonstrated severe atrophy with near total replacement of myocytes by fibrosis and dystrophic calcifications, and negative immunochemistry findings. In conclusion, these findings have defined an underappreciated complication of fetal antibody-mediated cardiac inflammation.

  8. Suppressor of cytokine signalling-3 expression inhibits cytokine-mediated destruction of primary mouse and rat pancreatic islets and delays allograft rejection

    DEFF Research Database (Denmark)

    Rønn, S G; Börjesson, A; Bruun, C;

    2008-01-01

    The pro-inflammatory cytokines IL-1 and IFNgamma are critical molecules in immune-mediated beta cell destruction leading to type 1 diabetes mellitus. Suppressor of cytokine signalling (SOCS)-3 inhibits the cytokine-mediated destruction of insulinoma-1 cells. Here we investigate the effect of SOCS...

  9. De-Novo anti-HLA Antibodies After Renal Transplantation: Prevalance and Risk Factors

    Directory of Open Access Journals (Sweden)

    Burak SUVAK

    2011-01-01

    Full Text Available AIM: Development of de-novo anti-HLA antibodies in the post-transplant period might be the earliest finding of later chronic antibody mediated rejection. In this study, we aimed to investigate the incidence and risk factors of de-novo anti-HLA antibodies in our kidney allograft recipients. MATERIAL and METHODS: After exclusion, 91 (64M/27F patients having functional graft and negative HLA antibody before the transplantation were taken into the analysis. Anti-HLA antibodies were evaluated by the Luminex method. RESULTS: Duration of posttransplantation time was 38±31 months and the mean age was 38±10. Mean estimated glomerular filtration rate (GFR was 68±19 ml/min, and the biopsy proven acute rejection rate was 15.2 %. Anti- HLA antibody was observed in 12 patients (13.1%. When the anti-HLA antibody positive group was compared with the negative group, estimated GFR (58±26 ml/min vs. 69±18 ml/ min, (p=0.05, living donor/cadaveric donor (5/7 vs. 66/13 (p=0.004, and acute rejection (6/12 (%50 vs. 8/79 (%10.1 (p=0.002 were significantly different between the groups. Deceased donor and acute rejection were independent risk factors for development of anti-HLA antibody (p=0.008 and p= 0.004, respectively on multivariate analysis. CONCLUSION: In conclusion, anti-HLA antibody can be seen after renal transplantation even in stable patients. Acute rejection and deceased donor transplantation are the major risk factors for development of anti-HLA antibodies.

  10. Chlamydia trachomatis and chlamydial heat shock protein 60-specific antibody and cell-mediated responses predict tubal factor infertility

    DEFF Research Database (Denmark)

    Tiitinen, A.; Surcel, H.-M.; Halttunen, M.;

    2006-01-01

    BACKGROUND: To evaluate the role of Chlamydia trachomatis-induced humoral and cell-mediated immune (CMI) responses in predicting tubal factor infertility (TFI). METHODS: Blood samples were taken from 88 women with TFI and 163 control women. C. trachomatis and chlamydial heat shock protein 60 (CHSP......60)-specific immunoglobulin G (IgG) antibodies were analysed using enzyme-linked immunosorbent assay (ELISA) kits. Proliferative reactivity of peripheral blood mononuclear cells was studied in vitro against Chlamydia elementary body (EB) and recombinant CHSP60 antigens. RESULTS: C. trachomatis-specific...

  11. Development of an edema factor-mediated cAMP-induction bioassay for detecting antibody-mediated neutralization of anthrax protective antigen.

    Science.gov (United States)

    Zmuda, Jonathan F; Zhang, Linyi; Richards, Terri; Pham, Quyen; Zukauskas, David; Pierre, Jennifer L; Laird, Michael W; Askins, Janine; Choi, Gil H

    2005-03-01

    Intoxication of mammalian cells by Bacillus anthracis requires the coordinate activity of three distinct bacterial proteins: protective antigen (PA), edema factor (EF), and lethal factor (LF). Among these proteins, PA has become the major focus of work on monoclonal antibodies and vaccines designed to treat or prevent anthrax infection since neither EF nor LF is capable of inducing cellular toxicity in its absence. Here, we present the development of a sensitive, precise, and biologically relevant bioassay platform capable of quantifying antibody-mediated PA neutralization. This bioassay is based on the ability of PA to bind and shuttle EF, a bacterial adenylate cyclase, into mammalian cells leading to an increase in cAMP that can be quantified using a sensitive chemiluminescent ELISA. The results of this study indicate that the cAMP-induction assay possesses the necessary performance characteristics for use as both a potency-indicating release assay in a quality control setting and as a surrogate pharmacodynamic marker for ensuring the continued bioactivity of therapeutic antibodies against PA during clinical trials. PMID:15847796

  12. TRADITIONAL AND CASCADE PLASMAPHERESIS IN ANTIBODY TITERS’ REDUCTION IN RENAL TRANSPLANT RECIPIENTS

    Directory of Open Access Journals (Sweden)

    A.V. Vatazin

    2014-01-01

    Full Text Available Introduction. One of the current tasks of transplantology is to overcome «graft-host» immune confl ict. Partially this confl ict is caused by the presence of circulating pre-existing antibodies. Highly sensitized patients have a greater risk of rejection and subsequent graft loss. There are several methods to remove the antibodies, one of which is a double fi ltration plasmapheresis (DFPF. This report presents our experience of DFPF in recipients of high immunologic risk.Aim: to compare the effectiveness of traditional and double filtration plasmapheresis in desensitization of patients with high risk of immunological complications.Methods. The study included 30 patients after kidney transplantation. All patients were classifi ed as high-immunologic risk group. In 15 patients of study group we performed DFPF, in 15 patients of comparison group – traditional plasmapheresis. We monitored the immune status: markers of humoral immunity activation – IgG, IgM, IgA before and after the procedures. DFPF procedure was performed on OctoNova (MeSys, Germany with a plasmafi lter and plasma components separator. Protocol biopsies were performed on days 30 and 90.Results. The concentration of antibodies may be effectively reduced with DFPF. Total IgM and IgG antibodies were reduced by 30–55% of the original level. There was a less albumin loss in case of DFPF application. There is 1 patient with antibody-mediated rejection with graft dysfunction in study group. There are no signs of rejection in 30- and 90-day biopsy in study group. But there were three patients with subclinical antibody-mediated rejection in the comparison group.Conclusion. DFPF can safely and effectively reduce the high titers of antibodies that are responsible for humoral rejection of renal allograft. Reduction of antibodies in sensitized patients immediately after transplantation may improve graft function.

  13. γδ T cell-mediated antibody-dependent cellular cytotoxicity with CD19 antibodies assessed by an impedance-based label-free real-time cytotoxicity assay

    OpenAIRE

    Ursula Jördis Eva Seidel; Fabian eVogt; Ludger eGrosse-Hovest; Gundram eJung; Rupert eHandgretinger; Peter eLang

    2014-01-01

    γδ T cells are not MHC restricted, elicit cytotoxicity against various malignancies, are present in early post-transplant phases in novel stem cell transplantation (SCT) strategies and have been shown to mediate antibody-dependent cellular cytotoxicity (ADCC) with monoclonal antibodies (mAbs). These features make γδ T cells promising effector cells for antibody-based immunotherapy in pediatric patients with B-lineage acute lymphoblastic leukemia (ALL). To evaluate combination of human γδ T ce...

  14. γδ T Cell-Mediated Antibody-Dependent Cellular Cytotoxicity with CD19 Antibodies Assessed by an Impedance-Based Label-Free Real-Time Cytotoxicity Assay

    OpenAIRE

    Seidel, Ursula Jördis Eva; Vogt, Fabian; Grosse-Hovest, Ludger; Jung, Gundram; Handgretinger, Rupert; Lang, Peter

    2014-01-01

    γδ T cells are not MHC restricted, elicit cytotoxicity against various malignancies, are present in early post-transplant phases in novel stem cell transplantation strategies and have been shown to mediate antibody-dependent cellular cytotoxicity (ADCC) with monoclonal antibodies (mAbs). These features make γδ T cells promising effector cells for antibody-based immunotherapy in pediatric patients with B-lineage acute lymphoblastic leukemia (ALL). To evaluate combination of human γδ T cells wi...

  15. Prospective Evaluation of Cetuximab-Mediated Antibody-Dependent Cell Cytotoxicity in Metastatic Colorectal Cancer Patients Predicts Treatment Efficacy.

    Science.gov (United States)

    Trotta, Anna Maria; Ottaiano, Alessandro; Romano, Carmela; Nasti, Guglielmo; Nappi, Anna; De Divitiis, Chiara; Napolitano, Maria; Zanotta, Serena; Casaretti, Rossana; D'Alterio, Crescenzo; Avallone, Antonio; Califano, Daniela; Iaffaioli, Rosario Vincenzo; Scala, Stefania

    2016-04-01

    Cetuximab is a monoclonal antibody to the EGFR that induces antibody-dependent cell cytotoxicity (ADCC) through Fcγ receptors on immune cells. Although SNPs in genes encoding Fcγ receptors are functionally relevant to cetuximab-mediated ADCC in colorectal cancer, a direct correlation betweenin vitroADCC and clinical response to cetuximab is not defined. We therefore enrolled 96 consecutive metastatic colorectal cancer (mCRC) patients at diagnosis in a study that assessed FcγR status and cetuximab-mediated ADCC. Patients carrying the FcγRIIaHalleles 131H/Hand 131H/Rhad significantly higher ADCC compared with patients with the 131R/Ralleles (P= 0.013). Patients carrying FcγRIIIa genotypes with theValleles 158V/Vand 158V/Fdisplayed higher ADCC compared with patients carrying the 158F/Fgenotype (P= 0.001). Progression-free survival of patients with an FcγRIIIa 158Vallele was significantly longer compared with patients carrying 158F/F(P= 0.05), whereas no significant difference was observed for overall survival. Twenty-eight of 50 mCRC patients with wild-type KRAS received cetuximab. The average ADCC-mediated killing was 30% of assay targets for patients who experienced cetuximab complete or partial response, 21% in patients with stable disease and 9% in patients with progressive disease. To characterize basal natural killer (NK) activity, cytotoxicity was evaluated in 39 of 96 mCRC patients. Patients who responded to first-line treatment had higher NK-cell cytotoxicity. Thus, although limited to this cohort of patients,in vitrocetuximab-mediated ADCC correlated with FcγR polymorphisms and predicted cetuximab responsiveness.Cancer Immunol Res; 4(4); 366-74. ©2016 AACR. PMID:26817995

  16. Control of Toll-like receptor-mediated T cell-independent type 1 antibody responses by the inducible nuclear protein IκB-ζ.

    Science.gov (United States)

    Hanihara-Tatsuzawa, Fumito; Miura, Hanae; Kobayashi, Shuhei; Isagawa, Takayuki; Okuma, Atsushi; Manabe, Ichiro; MaruYama, Takashi

    2014-11-01

    Antibody responses have been classified as being either T cell-dependent or T cell-independent (TI). TI antibody responses are further classified as being either type 1 (TI-1) or type 2 (TI-2), depending on their requirement for B cell-mediated antigen receptor signaling. Although the mechanistic basis of antibody responses has been studied extensively, it remains unclear whether different antibody responses share similarities in their transcriptional regulation. Here, we show that mice deficient in IκB-ζ, specifically in their B cells, have impaired TI-1 antibody responses but normal T cell-dependent and TI-2 antibody responses. The absence of IκB-ζ in B cells also impaired proliferation triggered by Toll-like receptor (TLR) activation, plasma cell differentiation, and class switch recombination (CSR). Mechanistically, IκB-ζ-deficient B cells could not induce TLR-mediated induction of activation-induced cytidine deaminase (AID), a class-switch DNA recombinase. Retroviral transduction of AID in IκB-ζ-deficient B cells restored CSR activity. Furthermore, acetylation of histone H3 in the vicinity of the transcription start site of the gene that encodes AID was reduced in IκB-ζ-deficient B cells relative to IκB-ζ-expressing B cells. These results indicate that IκB-ζ regulates TLR-mediated CSR by inducing AID. Moreover, IκB-ζ defines differences in the transcriptional regulation of different antibody responses. PMID:25124037

  17. Antibody-Mediated Neutralization of the Exotoxin Mycolactone, the Main Virulence Factor Produced by Mycobacterium ulcerans.

    Directory of Open Access Journals (Sweden)

    Jean-Pierre Dangy

    2016-06-01

    Full Text Available Mycolactone, the macrolide exotoxin produced by Mycobacterium ulcerans, causes extensive tissue destruction by inducing apoptosis of host cells. In this study, we aimed at the production of antibodies that could neutralize the cytotoxic activities of mycolactone.Using the B cell hybridoma technology, we generated a series of monoclonal antibodies with specificity for mycolactone from spleen cells of mice immunized with the protein conjugate of a truncated synthetic mycolactone derivative. L929 fibroblasts were used as a model system to investigate whether these antibodies can inhibit the biological effects of mycolactone. By measuring the metabolic activity of the fibroblasts, we found that anti-mycolactone mAbs can completely neutralize the cytotoxic activity of mycolactone.The toxin neutralizing capacity of anti-mycolactone mAbs supports the concept of evaluating the macrolide toxin as vaccine target.

  18. THE EXPERIENCE OF IMMUNOHISTOCHEMICAL INVESTIGATION OF ENDOMIOCARDIAL BIOPSIES FOR THE DIAGNOSIS OF THE HUMORAL REJECTION IN THE PATIENTS WITH HEART ALLOGRAFT

    Directory of Open Access Journals (Sweden)

    A. G. Kupriyanova

    2009-01-01

    Full Text Available The aim of present study was to characterize immunohistological features of humoral (antibody-mediated rejection, AMR by evaluating their manifestation, localization and distribution in endomiocardial biopsies (EMBs from patients after heart transplantation. The role of AMR in the development of allograft vasculopathy is investigated widely. The examine of more than 1000 EMBs maid it possible to elaborate the diagnostic criteria of acute humoral rejection, to characterize immunomorfological peculiarities of long-term heart allograft and demonstrated the relation AMR with the early development of coronary artery diseases. 

  19. Hapten mediated display and pairing of recombinant antibodies accelerates assay assembly for biothreat countermeasures.

    Science.gov (United States)

    Sherwood, Laura J; Hayhurst, Andrew

    2012-01-01

    A bottle-neck in recombinant antibody sandwich immunoassay development is pairing, demanding protein purification and modification to distinguish captor from tracer. We developed a simple pairing scheme using microliter amounts of E. coli osmotic shockates bearing site-specific biotinylated antibodies and demonstrated proof of principle with a single domain antibody (sdAb) that is both captor and tracer for polyvalent Marburgvirus nucleoprotein. The system could also host pairs of different sdAb specific for the 7 botulinum neurotoxin (BoNT) serotypes, enabling recognition of the cognate serotype. Inducible supE co-expression enabled sdAb populations to be propagated as either phage for more panning from repertoires or expressed as soluble sdAb for screening within a single host strain. When combined with streptavidin-g3p fusions, a novel transdisplay system was formulated to retrofit a semi-synthetic sdAb library which was mined for an anti-Ebolavirus sdAb which was immediately immunoassay ready, thereby speeding up the recombinant antibody discovery and utilization processes. PMID:23150778

  20. Different mechanisms are involved in the antibody mediated inhibition of ligand binding to the urokinase receptor

    DEFF Research Database (Denmark)

    List, K; Høyer-Hansen, G; Rønne, E;

    1999-01-01

    Certain monoclonal antibodies are capable of inhibiting the biological binding reactions of their target proteins. At the molecular level, this type of effect may be brought about by completely different mechanisms, such as competition for common binding determinants, steric hindrance or...

  1. Antibody therapy of cancer : Fc receptor-mediated mechanisms of action

    NARCIS (Netherlands)

    Overdijk, M.B.

    2013-01-01

    Cancer, a class of malignant diseases characterized by unregulated cell growth, is still a leading cause of death worldwide. The high specificity of antibodies combined with the ability to engage multiple mechanisms of action (MoA) and minimal side-effects makes them attractive agents for targeted t

  2. The strong in vivo anti-tumor effect of the UIC2 monoclonal antibody is the combined result of Pgp inhibition and antibody dependent cell-mediated cytotoxicity.

    Directory of Open Access Journals (Sweden)

    Gábor Szalóki

    Full Text Available P-glycoprotein (Pgp extrudes a large variety of chemotherapeutic drugs from the cells, causing multidrug resistance (MDR. The UIC2 monoclonal antibody recognizes human Pgp and inhibits its drug transport activity. However, this inhibition is partial, since UIC2 binds only to 10-40% of cell surface Pgps, while the rest becomes accessible to this antibody only in the presence of certain substrates or modulators (e.g. cyclosporine A (CsA. The combined addition of UIC2 and 10 times lower concentrations of CsA than what is necessary for Pgp inhibition when the modulator is applied alone, decreased the EC50 of doxorubicin (DOX in KB-V1 (Pgp+ cells in vitro almost to the level of KB-3-1 (Pgp- cells. At the same time, UIC2 alone did not affect the EC50 value of DOX significantly. In xenotransplanted severe combined immunodeficient (SCID mice co-treated with DOX, UIC2 and CsA, the average weight of Pgp+ tumors was only ∼10% of the untreated control and in 52% of these animals we could not detect tumors at all, while DOX treatment alone did not decrease the weight of Pgp+ tumors. These data were confirmed by visualizing the tumors in vivo by positron emission tomography (PET based on their increased 18FDG accumulation. Unexpectedly, UIC2+DOX treatment also decreased the size of tumors compared to the DOX only treated animals, as opposed to the results of our in vitro cytotoxicity assays, suggesting that immunological factors are also involved in the antitumor effect of in vivo UIC2 treatment. Since UIC2 binding itself did not affect the viability of Pgp expressing cells, but it triggered in vitro cell killing by peripheral blood mononuclear cells (PBMCs, it is concluded that the impressive in vivo anti-tumor effect of the DOX-UIC2-CsA treatment is the combined result of Pgp inhibition and antibody dependent cell-mediated cytotoxicity (ADCC.

  3. The strong in vivo anti-tumor effect of the UIC2 monoclonal antibody is the combined result of Pgp inhibition and antibody dependent cell-mediated cytotoxicity.

    Science.gov (United States)

    Szalóki, Gábor; Krasznai, Zoárd T; Tóth, Ágnes; Vízkeleti, Laura; Szöllősi, Attila G; Trencsényi, György; Lajtos, Imre; Juhász, István; Krasznai, Zoltán; Márián, Teréz; Balázs, Margit; Szabó, Gábor; Goda, Katalin

    2014-01-01

    P-glycoprotein (Pgp) extrudes a large variety of chemotherapeutic drugs from the cells, causing multidrug resistance (MDR). The UIC2 monoclonal antibody recognizes human Pgp and inhibits its drug transport activity. However, this inhibition is partial, since UIC2 binds only to 10-40% of cell surface Pgps, while the rest becomes accessible to this antibody only in the presence of certain substrates or modulators (e.g. cyclosporine A (CsA)). The combined addition of UIC2 and 10 times lower concentrations of CsA than what is necessary for Pgp inhibition when the modulator is applied alone, decreased the EC50 of doxorubicin (DOX) in KB-V1 (Pgp+) cells in vitro almost to the level of KB-3-1 (Pgp-) cells. At the same time, UIC2 alone did not affect the EC50 value of DOX significantly. In xenotransplanted severe combined immunodeficient (SCID) mice co-treated with DOX, UIC2 and CsA, the average weight of Pgp+ tumors was only ∼10% of the untreated control and in 52% of these animals we could not detect tumors at all, while DOX treatment alone did not decrease the weight of Pgp+ tumors. These data were confirmed by visualizing the tumors in vivo by positron emission tomography (PET) based on their increased 18FDG accumulation. Unexpectedly, UIC2+DOX treatment also decreased the size of tumors compared to the DOX only treated animals, as opposed to the results of our in vitro cytotoxicity assays, suggesting that immunological factors are also involved in the antitumor effect of in vivo UIC2 treatment. Since UIC2 binding itself did not affect the viability of Pgp expressing cells, but it triggered in vitro cell killing by peripheral blood mononuclear cells (PBMCs), it is concluded that the impressive in vivo anti-tumor effect of the DOX-UIC2-CsA treatment is the combined result of Pgp inhibition and antibody dependent cell-mediated cytotoxicity (ADCC). PMID:25238617

  4. Complement and Antibody-mediated Enhancement of Red Blood Cell Invasion and Growth of Malaria Parasites.

    Science.gov (United States)

    Biryukov, Sergei; Angov, Evelina; Landmesser, Mary E; Spring, Michele D; Ockenhouse, Christian F; Stoute, José A

    2016-07-01

    Plasmodium falciparum malaria is a deadly pathogen. The invasion of red blood cells (RBCs) by merozoites is a target for vaccine development. Although anti-merozoite antibodies can block invasion in vitro, there is no efficacy in vivo. To explain this discrepancy we hypothesized that complement activation could enhance RBC invasion by binding to the complement receptor 1 (CR1). Here we show that a monoclonal antibody directed against the merozoite and human polyclonal IgG from merozoite vaccine recipients enhanced RBC invasion in a complement-dependent manner and that soluble CR1 inhibited this enhancement. Sialic acid-independent strains, that presumably are able to bind to CR1 via a native ligand, showed less complement-dependent enhancement of RBC invasion than sialic acid-dependent strains that do not utilize native CR1 ligands. Confocal fluorescent microscopy revealed that complement-dependent invasion resulted in aggregation of CR1 at the RBC surface in contact with the merozoite. Finally, total anti-P. berghei IgG enhanced parasite growth and C3 deficiency decreased parasite growth in mice. These results demonstrate, contrary to current views, that complement activation in conjunction with antibodies can paradoxically aid parasites invade RBCs and should be considered in future design and testing of merozoite vaccines. PMID:27333049

  5. Antibody-mediated neutralization of Ebola virus can occur by two distinct mechanisms

    International Nuclear Information System (INIS)

    Human Ebola virus causes severe hemorrhagic fever disease with high mortality and there is no vaccine or treatment. Antibodies in survivors occur early, are sustained, and can delay infection when transferred into nonhuman primates. Monoclonal antibodies (mAbs) from survivors exhibit potent neutralizing activity in vitro and are protective in rodents. To better understand targets and mechanisms of neutralization, we investigated a panel of mAbs shown previously to react with the envelope glycoprotein (GP). While one non-neutralizing mAb recognized a GP epitope in the nonessential mucin-like domain, the rest were specific for GP1, were neutralizing, and could be further distinguished by reactivity with secreted GP. We show that survivor antibodies, human KZ52 and monkey JP3K11, were specific for conformation-dependent epitopes comprising residues in GP1 and GP2 and that neutralization occurred by two distinct mechanisms; KZ52 inhibited cathepsin cleavage of GP whereas JP3K11 recognized the cleaved, fusion-active form of GP.

  6. Spleen tyrosine kinase contributes to acute renal allograft rejection in the rat.

    Science.gov (United States)

    Ramessur Chandran, Sharmila; Tesch, Greg H; Han, Yingjie; Woodman, Naomi; Mulley, William R; Kanellis, John; Blease, Kate; Ma, Frank Y; Nikolic-Paterson, David J

    2015-02-01

    Kidney allografts induce strong T-cell and antibody responses which mediate acute rejection. Spleen tyrosine kinase (Syk) is expressed by most leucocytes, except mature T cells, and is involved in intracellular signalling following activation of the Fcγ-receptor, B-cell receptor and some integrins. A role for Syk signalling has been established in antibody-dependent native kidney disease, but little is known of Syk in acute renal allograft rejection. Sprague-Dawley rats underwent bilateral nephrectomy and received an orthotopic Wistar renal allograft. Recipient rats were treated with a Syk inhibitor (CC0482417, 30 mg/kg/bid), or vehicle, from 1 h before surgery until being killed 5 days later. Vehicle-treated recipients developed severe allograft failure with marked histologic damage in association with dense leucocyte infiltration (T cells, macrophages, neutrophils and NK cells) and deposition of IgM, IgG and C3. Immunostaining identified Syk expression by many infiltrating leucocytes. CC0482417 treatment significantly improved allograft function and reduced histologic damage, although allograft injury was still clearly evident. CC0482417 failed to prevent T-cell infiltration and activation within the allograft. However, CC0482417 significantly attenuated acute tubular necrosis, infiltration of macrophages and neutrophils and thrombosis of peritubular capillaries. In conclusion, this study identifies a role for Syk in acute renal allograft rejection. Syk inhibition may be a useful addition to T-cell-based immunotherapy in renal transplantation.

  7. Discerning Rejection of Technology

    Directory of Open Access Journals (Sweden)

    Sudhir Rama Murthy

    2013-04-01

    Full Text Available Technology is innate to modern society and primarily embodies human intellect. It greatly influences development, societal functioning, and sociotechnical transitions. Rapid technological advancements, made possible with advancement in science, human ingenuity, and competitive markets, provide human society with affordable and unlimited choice. A society can be viewed, with an individual as the fundamental unit, or as a community, or state/nation. In one view, sustainability can be viewed through a matrix of societal, economic, and environmental configurations associated with the three societal levels. Technological advancement and complexity can either remain simple and amenable to the user or, as emerging in recent years, may daunt the user to keep away. While the phenomenon of technology adoption (acceptance in society has been well appreciated, the increasingly characteristic phenomenon of technology rejection is yet to be understood and studied. Technology rejection is not merely a negation of its acceptance, and hence requires to be discerned carefully. Rejection also does not imply in its totality, but varies in terms of its kind and/or intensiveness. While rejection is discernable at all these three levels of society, this study remains focused at the level of the user (individual. It attempts to discern rejection of technology and discusses its distinctness from technology acceptance through an exhaustive literature study. The article initially discusses the technology–society nexus and provides a preliminary technology–user interface model leading to a detailed discussion into the determinants of technology rejection.

  8. Vascular endothelium as a target of immune response in renal transplant rejection.

    Science.gov (United States)

    Piotti, Giovanni; Palmisano, Alessandra; Maggiore, Umberto; Buzio, Carlo

    2014-01-01

    This review of clinical and experimental studies aims at analyzing the interplay between graft endothelium and host immune system in renal transplantation, and how it affects the survival of the graft. Graft endothelium is indeed the first barrier between self and non-self that is encountered by host lymphocytes upon reperfusion of vascularized solid transplants. Endothelial cells (EC) express all the major sets of antigens (Ag) that elicit host immune response, and therefore represent a preferential target in organ rejection. Some of the Ag expressed by EC are target of the antibody-mediated response, such as the AB0 blood group system, the human leukocyte antigens (HLA), and MHC class I related chain A antigens (MICA) systems, and the endothelial cell-restricted Ag; for each of these systems, the mechanisms of interaction and damage of both preformed and de novo donor-specific antibodies are reviewed along with their impact on renal graft survival. Moreover, the rejection process can force injured EC to expose cryptic self-Ag, toward which an autoimmune response mounts, overlapping to the allo-immune response in the damaging of the graft. Not only are EC a passive target of the host immune response but also an active player in lymphocyte activation; therefore, their interaction with allogenic T-cells is analyzed on the basis of experimental in vitro and in vivo studies, according to the patterns of expression of the HLA class I and II and the co-stimulatory molecules specific for cytotoxic and helper T-cells. Finally, as the response that follows transplantation has proven to be not necessarily destructive, the factors that foster graft endothelium functioning in spite of rejection, and how they could be therapeutically harnessed to promote long-term graft acceptance, are described: accommodation that is resistance of EC to donor-specific antibodies, and endothelial cell ability to induce Foxp3+ regulatory T-cells, that are crucial mediators of tolerance. PMID

  9. MP-4 Contributes to Snake Venom Neutralization by Mucuna pruriens Seeds through an Indirect Antibody-mediated Mechanism.

    Science.gov (United States)

    Kumar, Ashish; Gupta, Chitra; Nair, Deepak T; Salunke, Dinakar M

    2016-05-20

    Mortality due to snakebite is a serious public health problem, and available therapeutics are known to induce debilitating side effects. Traditional medicine suggests that seeds of Mucuna pruriens can provide protection against the effects of snakebite. Our aim is to identify the protein(s) that may be important for snake venom neutralization and elucidate its mechanism of action. To this end, we have identified and purified a protein from M. pruriens, which we have named MP-4. The full-length polypeptide sequence of MP-4 was obtained through N-terminal sequencing of peptide fragments. Sequence analysis suggested that the protein may belong to the Kunitz-type protease inhibitor family and therefore may potentially neutralize the proteases present in snake venom. Using various structural and biochemical tools coupled with in vivo assays, we are able to show that MP-4 does not afford direct protection against snake venom because it is actually a poor inhibitor of serine proteases. Further experiments showed that antibodies generated against MP-4 cross-react with the whole venom and provide protection to mice against Echis carinatus snake venom. This study shows that the MP-4 contributes significantly to the snake venom neutralization activity of M. pruriens seeds through an indirect antibody-mediated mechanism. PMID:26987900

  10. CD4+ T Lymphocytes are Not Necessary for the Acute Rejection of Vascularized Mouse Lung Transplants

    OpenAIRE

    Gelman, Andrew E.; Okazaki, Mikio; Lai, Jiaming; Kornfeld, Christopher G.; Kreisel, Friederike H.; Richardson, Steven B.; Sugimoto, Seiichiro; Tietjens, Jeremy R.; Patterson, G. Alexander; Krupnick, Alexander S.; Kreisel, Daniel

    2008-01-01

    Acute rejection continues to present a major obstacle to successful lung transplantation. While CD4+ T lymphocytes are critical for the rejection of some solid organ grafts the role of CD4+ T cells in the rejection of lung allografts is largely unknown. In this study we demonstrate in a novel model of orthotopic vascularized mouse lung transplantation that acute rejection of lung allografts is independent of CD4+ T cell-mediated allorecognition pathways. CD4+ T cell-independent rejection occu...

  11. B7h-expressing dendritic cells and plasma B cells mediate distinct outcomes of ICOS costimulation in T cell-dependent antibody responses

    Directory of Open Access Journals (Sweden)

    Larimore Kevin

    2012-06-01

    Full Text Available Abstract Background The ICOS-B7h costimulatory receptor-ligand pair is required for germinal center formation, the production of isotype-switched antibodies, and antibody affinity maturation in response to T cell-dependent antigens. However, the potentially distinct roles of regulated B7h expression on B cells and dendritic cells in T cell-dependent antibody responses have not been defined. Results We generated transgenic mice with lineage-restricted B7h expression to assess the cell-type specific roles of B7h expression on B cells and dendritic cells in regulating T cell-dependent antibody responses. Our results show that endogenous B7h expression is reduced on B cells after activation in vitro and is also reduced in vivo on antibody-secreting plasma B cells in comparison to both naïve and germinal center B cells from which they are derived. Increasing the level of B7h expression on activated and plasma B cells in B-B7hTg mice led to an increase in the number of antibody-secreting plasma cells generated after immunization and a corresponding increase in the concentration of antigen-specific high affinity serum IgG antibodies of all isotypes, without affecting the number of responding germinal center B cells. In contrast, ICOS costimulation mediated by dendritic cells in DC-B7hTg mice contributed to germinal center formation and selectively increased IgG2a production without affecting the overall magnitude of antibody responses. Conclusions Using transgenic mice with lineage-restricted B7h expression, we have revealed distinct roles of ICOS costimulation mediated by dendritic cells and B cells in the regulation of T cell-dependent antibody responses.

  12. Sialyl-Tn vaccine induces antibody-mediated tumour protection in a relevant murine model

    DEFF Research Database (Denmark)

    Julien, S; Picco, G; Sewell, R;

    2009-01-01

    be carried on various glycoproteins. One such glycoprotein MUC1 is expressed by the vast majority of breast carcinomas. Both STn and MUC1 have been considered as targets for immunotherapy of breast cancer patients. Here we used different immunogens to target STn in an MUC1 transgenic mouse model of tumour......Changes in the composition of glycans added to glycoproteins and glycolipids are characteristic of the change to malignancy. Sialyl-Tn (STn) is expressed by 25-30% of breast carcinomas but its expression on normal tissue is highly restricted. Sialyl-Tn is an O-linked disaccharide that can...... challenge. We show that synthetic STn coupled to keyhole limpet haemocyanin (Theratope), induced antibodies to STn that recognised the glycan carried on a number of glycoproteins and in these mice a significant delay in tumour growth was observed. The protection was dependent on STn being expressed...

  13. A clinico-radiological phenotype of voltage-gated potassium channel complex antibody-mediated disorder presenting with seizures and basal ganglia changes.

    Science.gov (United States)

    Hacohen, Yael; Wright, Sukhvir; Siddiqui, Ata; Pandya, Nikki; Lin, Jean-Pierre; Vincent, Angela; Lim, Ming

    2012-12-01

    In childhood, central nervous system (CNS) presentations associated with antibodies to voltage-gated potassium channel (VGKC) complex include limbic encephalitis, status epilepticus, epileptic encephalopathy, and autistic regression. We report the cases of two individuals (a 6-year-old male and an 11-year-old female) who presented with an acute-onset explosive seizure disorder with positive VGKC complex antibodies and bilateral basal ganglia changes on magnetic resonance imaging (MRI). Both patients made a complete clinical recovery, without immunotherapy, with resolution of the MRI changes and normalization of the antibody levels. Extended antibody testing, including testing for leucine-rich glioma-inactivated 1 (LGI1), contactin-associated protein 2, and contactin-2 was negative. This could suggest that the clinico-radiological phenotype in our patients may in fact be associated with a novel autoreactive target(s) within the VGKC complex, as may be the case in other children with VGKC complex-mediated CNS disorders.

  14. Corneal allograft rejection: Risk factors, diagnosis, prevention, and treatment

    Directory of Open Access Journals (Sweden)

    Dua Harminder

    1999-01-01

    Full Text Available Recent advances in corneal graft technology, including donor tissue retrieval, storage and surgical techniques, have greatly improved the clinical outcome of corneal grafts. Despite these advances, immune mediated corneal graft rejection remains the single most important cause of corneal graft failure. Several host factors have been identified as conferring a "high risk" status to the host. These include: more than two quadrant vascularisation, with associated lymphatics, which augment the afferent and efferent arc of the immune response; herpes simplex keratitis; uveitis; silicone oil keratopathy; previous failed (rejected grafts; "hot eyes"; young recipient age; and multiple surgical procedures at the time of grafting. Large grafts, by virtue of being closer to the host limbus, with its complement of vessels and antigen-presenting Langerhans cells, also are more susceptible to rejection. The diagnosis of graft rejection is entirely clinical and in its early stages the clinical signs could be subtle. Graft rejection is largely mediated by the major histocompatibility antigens, minor antigens and perhaps blood group ABO antigens and some cornea-specific antigens. Just as rejection is mediated by active immune mediated events, the lack of rejection (tolerance is also sustained by active immune regulatory mechanisms. The anterior chamber associated immune deviation (ACAID and probably, conjunctiva associated lymphoid tissue (CALT induced mucosal tolerance, besides others, play an important role. Although graft rejection can lead to graft failure, most rejections can be readily controlled if appropriate management is commenced at the proper time. Topical steroids are the mainstay of graft rejection management. In the high-risk situations however, systemic steroids, and other immunosuppressive drugs such as cyclosporin and tacrolimus (FK506 are of proven benefit, both for treatment and prevention of rejection.

  15. Characterization of the mechanism of protection mediated by CS-D7, a monoclonal antibody to Staphylococcus aureus iron regulated surface determinant B (IsdB)

    OpenAIRE

    Gregory ePancari; Hongxia eFan; Sharon eSmith; Amita eJoshi; Robin eHaimbach; Desmond eClark; Yingzhe eLi; Jin eHua; Troy eMcKelvey; Yangsi eOu; James eDrummond; Leslie eCope; Donna eMontgomery; Tessie eMcNeely

    2012-01-01

    We previously reported the development of a human monoclonal antibody (CS-D7, IgG1) with specificity and affinity for the iron regulated surface determinant B (IsdB) of Staphylococcus aureus. CS-D7 mediates opsonophagocytic killing in vitro and protection in a murine sepsis model. In light of recent data indicating that IsdB specific T cells (CD4+, Th17), not Ab, mediate protection after vaccination with IsdB, it is important to investigate the mechanism of protection mediated by CS-D7. Th...

  16. Blockade of 4-1BB/4-1BB ligand interactions prevents acute rejection in rat liver transplantation

    Institute of Scientific and Technical Information of China (English)

    QIN Lei; GUAN Hong-geng; ZHOU Xiao-jun; YIN Jun; LAN Jing; QIAN Hai-xin

    2010-01-01

    Background Blocking the 4-1BB/4-1BB ligand (4-1BBL) signal may modulate the secretion of Th1/Th2 cytokines and prolong the survival of the grafts, which play a key role in organ transplantation tolerance. The aim of this study was to investigate the role of blockade of the 4-1BB/4-1BBL co-stimulatory pathway with 4-1 BBL monoclonal antibody (mAB) in acute rejection of rat orthotopic liver transplantation. Methods The orthotopic liver transplantation model was set up, while male Lewis rats were used as liver donors and Brown-Norway rats as recipients. The recipient rats were intravenously injected with anti 4-1BBL mAB or isotype control antibody. Groups were monitored for graft survival after transplantation. Plasma chemistry, including aspartate transaminase (AST), alanine aminotransferase (ALT), and bilirubin (BIL), was assayed. The concentrations of interleukin (IL)-2, IL-10 and interferon (IFN)- γ in plasma were also measured by enzyme-linked immunosorbent assay. Allograft histology images were collected under light microscope and electron microscope. Results Isotype antibody treated recipients exhibited elevated plasma levels of liver injury markers including AST, ALT and BIL, progressive portal and venous inflammation and cellular infiltration of the liver allografts, and a mean graft survival time (MST) of 10.9 days. Administration of anti 4-1 BBL mAB resulted in a decrease in plasma levels of liver injury markers and the concentrations of IL-2, IL-10 and IFN-γ. The histological grade of rejection on day 7 decreased and MST (17.3 days) increased substantially.Conclusions These results demonstrate that attenuation of acute rejection follows the blockade of the 4-1BB/4-1BBL co-stimulatory pathway with 4-1BBL monoclonal antibody and strongly suggest it is a promising strategy to prevent progression of graft rejection by suppressing T cell-mediated immunity.

  17. Complement-mediated, antibody-dependent enhancement of HIV-1 infection in vitro is characterized by increased protein and RNA syntheses and infectious virus release.

    Science.gov (United States)

    Robinson, W E; Montefiori, D C; Gillespie, D H; Mitchell, W M

    1989-01-01

    Antibody-dependent enhancement (ADE) of human immunodeficiency virus type 1 (HIV-1) infection in vitro has been described recently and was shown to occur by two mechanisms: either participation of the alternative pathway of complement or to involve an Fc receptor-mediated, complement-independent mechanism. Complement-mediated ADE results in an accelerated cytopathic effect in target cells that can abrogate the protective properties of neutralizing antibodies. This study characterizes the surface antigens of MT-2 cells using flow cytometric analysis and shows that these cells express high levels of both CD4 and complement receptor type 2 (CR2) while several CD4+ cell lines that do not demonstrate complement-mediated ADE lack high levels of complement receptors. Further, utilizing MT-2 cell cultures, it is demonstrated that complement-mediated ADE of HIV-1 infection is conferred by the sera from more than 80% of HIV-1 antibody-positive individuals (N = 85). Complement-mediated ADE of HIV-1 infection causes an acceleration of several parameters indicative of HIV-1 infection in vitro including increased HIV-1 antigen synthesis as detected by indirect immunofluorescence, RNA accumulation as measured by a solution hybridization protocol, reverse transcriptase release, and progeny virus production. PMID:2465404

  18. Hyperacute Rejection of a Living Unrelated Kidney Graft

    Directory of Open Access Journals (Sweden)

    Dietlind Tittelbach-Helmrich

    2014-01-01

    Full Text Available We present a case report of a 59-year-old man, who received a blood group identical living unrelated kidney graft. This was his second kidney transplantation. Pretransplant T-cell crossmatch resulted negative. B-cell crossmatch, which is not considered a strict contraindication for transplantation, resulted positive. During surgery no abnormalities occurred. Four hours after the transplantation diuresis suddenly decreased. In an immediately performed relaparotomy the transplanted kidney showed signs of hyperacute rejection and had to be removed. Pathological examination was consistent with hyperacute rejection. Depositions of IgM or IgG antibodies were not present in pathologic evaluation of the rejected kidney, suggesting that no irregular endothelial specific antibodies had been involved in the rejection. We recommend examining more closely recipients of second allografts, considering not only a positive T-cell crossmatch but also a positive B-cell crossmatch as exclusion criteria for transplantation.

  19. HVR1-mediated antibody evasion of highly infectious in vivo adapted HCV in humanised mice

    DEFF Research Database (Denmark)

    Prentoe, Jannick; Verhoye, Lieven; Velázquez Moctezuma, Rodrigo;

    2016-01-01

    OBJECTIVE: HCV is a major cause of chronic liver disease worldwide, but the role of neutralising antibodies (nAbs) in its natural history remains poorly defined. We analysed the in vivo role of hypervariable region 1 (HVR1) for HCV virion properties, including nAb susceptibility. DESIGN: Analysis...... of HCV from human liver chimeric mice infected with cell-culture-derived prototype genotype 2a recombinant J6/JFH1 or HVR1-deleted variant J6/JFH1ΔHVR1 identified adaptive mutations, which were analysed by reverse genetics in Huh7.5 and CD81-deficient S29 cells. The increased in vivo genomic stability......06 IgG in vitro. CONCLUSIONS: The A876P-substitution bridges in vitro and in vivo studies using J6/JFH1-based recombinants. We provide the first in vivo evidence that HVR1 protects cross-genotype conserved HCV neutralisation epitopes, which advocates the possibility of using HVR1-deleted viruses...

  20. SOC REJECTION BY NANOFILTRATION

    Science.gov (United States)

    A study was conducted to evaluate the rejection of six synthetic organic compounds (SOCs) from a potable water source by a nanofiltration membrane process. The S0Cs were ethylene dibromide (EDB), dibromochloropropane (DBCP), chlordane, heptachlor, methoxychlor and alachlor. To in...

  1. Importance of (antibody-dependent) complement-mediated serum killing in protection against Bordetella pertussis.

    Science.gov (United States)

    Geurtsen, Jeroen; Fae, Kellen C; van den Dobbelsteen, Germie P J M

    2014-10-01

    Pertussis is a highly contagious respiratory disease that is caused by Bordetella pertussis. Despite being vaccine preventable, pertussis rates have been rising steadily over the last decades, even in areas with high vaccine uptake. Recently, experiments with infant baboons indicated that although vaccination with acellular pertussis vaccines prevented disease, no apparent effect was observed on infection and transmission. One explanation may be that current acellular pertussis vaccines do not induce high levels of opsonophagocytic and/or bactericidal activity, implying that engineering of vaccines that promote bacterial killing may improve efficacy. Here, we discuss the importance of complement-mediated killing in vaccine-induced protection against B. pertussis. We first examine how B. pertussis may have evolved different complement evasion strategies. Second, we explore the benefits of opsonophagocytic and/or bactericidal killing in vaccine-induced protection and discuss whether or not inclusion of new opsonophagocytic or bactericidal target antigens in pertussis vaccines may benefit efficacy.

  2. Heterosexual Rejection and Mate Choice: A Sociometer Perspective

    Directory of Open Access Journals (Sweden)

    Lin eZHANG

    2015-12-01

    Full Text Available Previous studies about the effects of social rejection on individuals’ social behaviors have produced mixed results and tend to study mating behaviors from a static point of view. However, mate selection in essence is a dynamic process, and therefore sociometer theory opens up a new perspective for studying mating and its underlying practices. Based on this theory and using self-perceived mate value in the relationship between heterosexual rejection and mate choice as a mediating role, this current study examined the effects of heterosexual rejection on mate choice in two experiments. Results showed that heterosexual rejection significantly reduced self-perceived mate value, expectation, and behavioral tendencies, while heterosexual acceptance indistinctively increased these measures. Self-perceived mate value did not serve as a mediator in the relationship between heterosexual rejection and mate expectation, but it mediated the relationship between heterosexual rejection and mating behavior tendencies towards potential objects. Moreover, individuals evaded both rejection and irrelevant people when suffering from rejection.

  3. Mechanisms mediating enhanced neutralization efficacy of staphylococcal enterotoxin B by combinations of monoclonal antibodies.

    Science.gov (United States)

    Dutta, Kaushik; Varshney, Avanish K; Franklin, Matthew C; Goger, Michael; Wang, Xiaobo; Fries, Bettina C

    2015-03-13

    Staphylococcal enterotoxin B (SEB) is a superantigen that cross-links the major histocompatibility complex class II and specific V-β chains of the T-cell receptor, thus forming a ternary complex. Developing neutralizing mAb to disrupt the ternary complex and abrogate the resulting toxicity is a major therapeutic challenge because SEB is effective at very low concentrations. We show that combining two SEB-specific mAbs enhances their efficacy, even though one of the two mAbs by itself has no effect on neutralization. Crystallography was employed for fine-mapping conformational epitopes in binary and ternary complexes between SEB and Fab fragments. NMR spectroscopy was used to validate and identify subtle allosteric changes induced by mAbs binding to SEB. The mapping of epitopes established that a combination of different mAbs can enhance efficacy of mAb-mediated protection from SEB induced lethal shock by two different mechanisms: one mAb mixture promoted clearance of the toxin both in vitro and in vivo by FcR-mediated cross-linking and clearance, whereas the other mAb mixture induced subtle allosteric conformational changes in SEB that perturbed formation of the SEB·T-cell receptor·major histocompatibility complex class II trimer. Finally structural information accurately predicted mAb binding to other superantigens that share conformational epitopes with SEB. Fine mapping of conformational epitopes is a powerful tool to establish the mechanism and optimize the action of synergistic mAb combinations. PMID:25572397

  4. Erythropoietin enhances nerve repair in anti-ganglioside antibody-mediated models of immune neuropathy.

    Directory of Open Access Journals (Sweden)

    Gang Zhang

    Full Text Available Guillain-Barré syndrome (GBS is a monophasic immune neuropathic disorder in which a significant proportion of patients have incomplete recovery. The patients with incomplete recovery almost always have some degree of failure of axon regeneration and target reinnervation. Anti-ganglioside antibodies (Abs are the most commonly recognized autoimmune markers in all forms of GBS and specific Abs are associated with the slow/poor recovery. We recently demonstrated that specific anti-ganglioside Abs inhibit axonal regeneration and nerve repair in preclinical models by activation of small GTPase RhoA and its downstream effectors. The objective of this study was to determine whether erythropoietin (EPO, a pleiotropic cytokine with neuroprotective and neurotrophic properties, enhances nerve regeneration in preclinical cell culture and animal models of autoimmune neuropathy/nerve repair generated with monoclonal and patient derived Abs. Primary neuronal cultures and a standardized sciatic crush nerve model were used to assess the efficacy of EPO in reversing inhibitory effects of anti-ganglioside Abs on nerve repair. We found that EPO completely reversed the inhibitory effects of anti-ganglioside Abs on axon regeneration in cell culture models and significantly improved nerve regeneration/repair in an animal model. Moreover, EPO-induced proregenerative effects in nerve cells are through EPO receptors and Janus kinase 2/Signal transducer and activator of transcription 5 pathway and not via early direct modulation of small GTPase RhoA. These preclinical studies indicate that EPO is a viable candidate drug to develop further for neuroprotection and enhancing nerve repair in patients with GBS.

  5. Transgenic mice designed to express human α-1,2-fucosyltransferase in combination of human DAF and CD59 to avoid xenograft rejection

    Institute of Scientific and Technical Information of China (English)

    LIU BingQian; CHENG ChuanYu; WU YuDong; WEI JinXing; LI GuangSan; MA TengXiang

    2008-01-01

    The expression of human α-1,2-fucosyltransferase (HT) or complement regulatory proteins has been proved as an strategy to overcome hypercute rejection in discordant xenogeneic organ transplantation.In this study, we examined whether peripheral blood mononuclear cells (PBMCs) from polytransgenic mice expressing the human HT, and complement regulatory proteins (DAF and CD59), can provide more effective protection against xenograft rejection. Transgenic mice were produced by co-injection of gene constructs for human HT, DAF and/or CD59. Flow Cytometry (FCM) was used to screen the positive transgenic mice. PBMCs from transgenic mice were incubated with 15% human serum to evaluate natural antibody binding, complement activation and expression of adhesion molecules.Three transgenes were strongly expressed in PBMCs of transgenic mice, and HT expression significantly reduced expression of the major xenoepitope galactose-α-1,3-galactose (α-Gal). Functional studies with PBMCs showed that co-expression of HT and DAF or CD59 markedly increased their resistance to human serum-mediated cytolysis when compared with single transgenic PBMCs. Moreover,the combined expression of triple transgenes in PBMCs led to the greatest protection against human serum-mediated cytolyais, avoided hyperacute rejection and reduced expression of adhesion molecules. Strong co-expression of triple transgenes was completely protected from xenograft hyperacute rejection and partially inhibited acute vascular rejection. The studies suggest that engineering mice to express triple molecules represents an critical step toward prolonging xenograft survival and might be more suitable for xenotransplantation.

  6. Transgenic mice designed to express human α-1,2-fucosyltransferase in combination of human DAF and CD59 to avoid xenograft rejection

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The expression of human α-1,2-fucosyltransferase (HT) or complement regulatory proteins has been proved as an strategy to overcome hypercute rejection in discordant xenogeneic organ transplantation. In this study, we examined whether peripheral blood mononuclear cells (PBMCs) from polytransgenic mice expressing the human HT, and complement regulatory proteins (DAF and CD59), can provide more effective protection against xenograft rejection. Transgenic mice were produced by co-injection of gene constructs for human HT, DAF and/or CD59. Flow Cytometry (FCM) was used to screen the positive transgenic mice. PBMCs from transgenic mice were incubated with 15% human serum to evaluate natural antibody binding, complement activation and expression of adhesion molecules. Three transgenes were strongly expressed in PBMCs of transgenic mice, and HT expression signifi- cantly reduced expression of the major xenoepitope galactose-α-1,3-galactose (α-Gal). Functional studies with PBMCs showed that co-expression of HT and DAF or CD59 markedly increased their re- sistance to human serum-mediated cytolysis when compared with single transgenic PBMCs. Moreover, the combined expression of triple transgenes in PBMCs led to the greatest protection against human serum-mediated cytolysis, avoided hyperacute rejection and reduced expression of adhesion mole- cules. Strong co-expression of triple transgenes was completely protected from xenograft hyperacute rejection and partially inhibited acute vascular rejection. The studies suggest that engineering mice to express triple molecules represents an critical step toward prolonging xenograft survival and might be more suitable for xenotransplantation.

  7. Daratumumab-mediated lysis of primary multiple myeloma cells is enhanced in combination with the human anti-KIR antibody IPH2102 and lenalidomide

    Science.gov (United States)

    Nijhof, Inger S.; van Bueren, Jeroen J. Lammerts; van Kessel, Berris; Andre, Pascale; Morel, Yannis; Lokhorst, Henk M.; van de Donk, Niels W.C.J.; Parren, Paul W.H.I.; Mutis, Tuna

    2015-01-01

    Despite recent treatment improvements, multiple myeloma remains an incurable disease. Since antibody-dependent cell-mediated cytotoxicity is an important effector mechanism of daratumumab, we explored the possibility of improving daratumumab-mediated cell-mediated cytotoxicity by blocking natural killer cell inhibitory receptors with the human monoclonal anti-KIR antibody IPH2102, next to activation of natural killer cells with the immune modulatory drug lenalidomide. In 4-hour antibody-dependent cell-mediated cytotoxicity assays, IPH2102 did not induce lysis of multiple myeloma cell lines, but it did significantly augment daratumumab-induced myeloma cell lysis. Also in an ex vivo setting, IPH2102 synergistically improved daratumumab-dependent lysis of primary myeloma cells in bone marrow mononuclear cells (n=21), especially in patients carrying the FcγRIIIa-158F allele or the FcγRIIa-131R allele, who bind IgG1 with lower affinity than patients carrying the FcγRIIIa-158V allele or the FcγRIIa-131H allele. Finally, a further synergistically improved myeloma cell lysis with the daratumumab-IPH2102 combination was observed by adding lenalidomide, which suggests that more effective treatment strategies can be designed for multiple myeloma by combining daratumumab with agents that independently modulate natural killer cell function. PMID:25510242

  8. Fab-mediated binding of drug-dependent antibodies to platelets in quinidine- and quinine-induced thrombocytopenia.

    OpenAIRE

    Christie, D J; Mullen, P C; Aster, R H

    1985-01-01

    Platelets coated with quinine- or quinidine-induced antibodies form rosettes around protein A-Sepharose beads and normal platelets form rosettes about protein A-Sepharose beads coated with these antibodies. These reactions occurred only in the presence of sensitizing drug. Platelets also formed rosettes about protein A-Sepharose beads coated with an anti-PIA1 antibody, but drug was not required. Formation of rosettes between antibody-coated platelets and protein A-Sepharose was inhibited by F...

  9. 致敏肾移植受者抗MICA抗体的表达对术后早期排斥反应和肾功能的影响%Expression of anti-MICA antibodies and its influence on acute rejection and allograft function of sensitized renal recipients in early post-transplant course

    Institute of Scientific and Technical Information of China (English)

    张小东; 杨晓勇; 李晓北; 张际青; 杨毅; 尹航; 胡小鹏; 任亮; 王玮; 刘航

    2010-01-01

    Objective To explore the expression of anti-MICA antibodies and evaluate its influence on acute rejection and renal function in early period after renal transplantation. Methods A total of 29 sensitized subjects (PRA>20 %) were enrolled in this study. All the patients underwent protein A immunoabsorption treatment and the expression of anti-MICA antibodies was detected before and after treatment. Triple immunosuppressive regimen consisting of tacrolimus, mycophenolate mofetil (MMF) and steroid was given to prevent graft rejection. The correlation between the expression of anti-MICA antibodies and acute rejection or serum creatinine (SCr) level was analyzed.Results The expression of anti-MICA antibodies was detected in 8 candidates (27. 6 % ,8/29) ,and 6 kinds of anti-MICA antibodies simultaneously expressed were found in one individual, 3 kinds in one case,and sole kind in 6 patients. There was no significant difference in acute rejection rate between positive anti-MICA antibodies group and negative group [37.5 % (3/8) vs 38. 1% (8/21), P>0.05). The positive expression rate of anti-MICA antibodies in the recipients with PRA ≥40% was higher than that in those with PRA <40% [43. 8 % (7/16) vs 7. 7 % (1/13),P<0.05]. The SCr level in patients positive for anti-MICA antibodies was markedly higher than that in those negative anti-MICA antibodies at the 1st week postoperatively ( 135.4 ± 21.4 vs 108. 6 -+ 31.6 μmol/L, P<0.05). The SCr level in the patients with positive anti-MICA antibodies, however, was reduced to the normal range at the 2nd week after surgery (P>0.05). The levels of anti-MICA antibodies were continuously decreased in the candidates undergoing protein A irnmunoadsorption treatment. Conclusion Higher expression of anti-MICA antibodies exists in sensitized recipients and possesses an influence on the recovery of renal function in early postoperative period. Protein A immunoadsorption can eliminate anti-MICA antibodies effectively in

  10. Anti-Glycoprotein G Antibodies of Herpes Simplex Virus 2 Contribute to Complete Protection after Vaccination in Mice and Induce Antibody-Dependent Cellular Cytotoxicity and Complement-Mediated Cytolysis

    Directory of Open Access Journals (Sweden)

    Staffan Görander

    2014-11-01

    Full Text Available We investigated the role of antibodies against the mature portion of glycoprotein G (mgG-2 of herpes simplex virus 2 (HSV-2 in protective immunity after vaccination. Mice were immunized intramuscularly with mgG-2 and oligodeoxynucleotides containing two CpG motifs plus alum as adjuvant. All C57BL/6 mice survived and presented no genital or systemic disease. High levels of immunoglobulin G subclass 1 (IgG1 and IgG2 antibodies were detected and re-stimulated splenic CD4+ T cells proliferated and produced IFN-γ. None of the sera from immunized mice exhibited neutralization, while all sera exerted antibody-dependent cellular cytotoxicity (ADCC and complement-mediated cytolysis (ACMC activity. Passive transfer of anti-mgG-2 monoclonal antibodies, or immune serum, to naive C57BL/6 mice did not limit disease progression. Immunized B‑cell KO mice presented lower survival rate and higher vaginal viral titers, as compared with vaccinated B-cell KO mice after passive transfer of immune serum and vaccinated C57BL/6 mice. Sera from mice that were vaccinated subcutaneously and intranasally with mgG-2 presented significantly lower titers of IgG antibodies and lower ADCC and ACMC activity. We conclude that anti-mgG-2 antibodies were of importance to limit genital HSV‑2 infection. ADCC and ACMC activity are potentially important mechanisms in protective immunity, and could tentatively be evaluated in future animal vaccine studies and in clinical trials.

  11. 抗MICA抗体的产生途径及其对肾移植后急性排斥反应治疗效果的影响%Anti-MICA antibodies: production path and impact on therapeutic efficacy after renal transplantation with acute rejection

    Institute of Scientific and Technical Information of China (English)

    于立新; 刘如敏; 罗敏; 肖露露; 付绍杰; 王亦斌; 张新科

    2012-01-01

    目的 探讨抗多态性主要组织相容性复合体Ⅰ类相关链A(MICA)抗体的产生途径及其对肾移植后急性排斥反应(AR)治疗效果的影响.方法 随机抽取等待肾移植者157例,采用Luminex200液相芯片分析技术检测抗MICA抗体及其特异性,并采集临床资料,分析抗MICA抗体的产生途径及其免疫球蛋白类型,进而探讨IgM型抗MICA抗体与IgM和IgG复合型抗MICA抗体对肾移植后急性排斥反应(AR)发生率和治疗效果的影响.结果 157例中,既往有输血、妊娠、移植史者68例,移植前抗MICA抗体阳性者19例(27.9%);既往没有致敏经历者89例,移植前抗MICA抗体阳性者26例(29.2%),二者间抗MICA抗体阳性率的差异无统计学意义(P>0.05).抗MICA抗体阳性者45例,其中26例(57.8%)既往无致敏经历,其抗MICA抗体类型为IgM;另19例(42.2%)有已知的一种或多种致敏经历,其抗MICA抗体类型为IgG和IgM复合型.抗MICA抗体阳性的45例,有38例接受了肾移植,其中22例IgM型抗MICA抗体者,有7例(31.8%)发生AR,经甲泼尼龙冲击治疗均获得逆转,另16例IgM和IgG复合型抗MICA抗体者亦有7例(43.8%)发生AR,经甲泼尼龙等治疗,3例(42.9%)逆转,4例移植肾功能丧失;两种免疫球蛋白类型抗MICA抗体阳性者间肾移植后AR发生率的差异无统计学意义(P>0.05),但AR逆转率的差异有统计学意义(P<0.05).结论 对于无致敏史者其抗MICA抗体的产生可能存在经典的“天然抗体”的产生途径,其免疫球蛋白类型为IgM,肾移植后若发生AR,治疗转归较好;而对于移植前预存IgG和IgM复合型抗MICA抗体者,因其AR治疗的转归不佳,需予以足够重视.%Objective To investigate the production path of major histocompatibility complex class Ⅰ chain-related gene A(MICA) antibodies and the impact on the therapeutic efficacy after acute rejection in renal transplantation recipients.Methods Luminex flow cytometry was used to

  12. Modeling rejection immunity

    Directory of Open Access Journals (Sweden)

    Gaetano Andrea De

    2012-05-01

    Full Text Available Abstract Background Transplantation is often the only way to treat a number of diseases leading to organ failure. To overcome rejection towards the transplanted organ (graft, immunosuppression therapies are used, which have considerable side-effects and expose patients to opportunistic infections. The development of a model to complement the physician’s experience in specifying therapeutic regimens is therefore desirable. The present work proposes an Ordinary Differential Equations model accounting for immune cell proliferation in response to the sudden entry of graft antigens, through different activation mechanisms. The model considers the effect of a single immunosuppressive medication (e.g. cyclosporine, subject to first-order linear kinetics and acting by modifying, in a saturable concentration-dependent fashion, the proliferation coefficient. The latter has been determined experimentally. All other model parameter values have been set so as to reproduce reported state variable time-courses, and to maintain consistency with one another and with the experimentally derived proliferation coefficient. Results The proposed model substantially simplifies the chain of events potentially leading to organ rejection. It is however able to simulate quantitatively the time course of graft-related antigen and competent immunoreactive cell populations, showing the long-term alternative outcomes of rejection, tolerance or tolerance at a reduced functional tissue mass. In particular, the model shows that it may be difficult to attain tolerance at full tissue mass with acceptably low doses of a single immunosuppressant, in accord with clinical experience. Conclusions The introduced model is mathematically consistent with known physiology and can reproduce variations in immune status and allograft survival after transplantation. The model can be adapted to represent different therapeutic schemes and may offer useful indications for the optimization of

  13. Heat rejection system

    Science.gov (United States)

    Smith, Gregory C.; Tokarz, Richard D.; Parry, Jr., Harvey L.; Braun, Daniel J.

    1980-01-01

    A cooling system for rejecting waste heat consists of a cooling tower incorporating a plurality of coolant tubes provided with cooling fins and each having a plurality of cooling channels therein, means for directing a heat exchange fluid from the power plant through less than the total number of cooling channels to cool the heat exchange fluid under normal ambient temperature conditions, means for directing water through the remaining cooling channels whenever the ambient temperature rises above the temperature at which dry cooling of the heat exchange fluid is sufficient and means for cooling the water.

  14. Dextrose-mediated aggregation of therapeutic monoclonal antibodies in human plasma: Implication of isoelectric precipitation of complement proteins.

    Science.gov (United States)

    Luo, Shen; Zhang, Baolin

    2015-01-01

    Many therapeutic monoclonal antibodies (mAbs) are clinically administered through intravenous infusion after mixing with a diluent, e.g., saline, 5% dextrose. Such a clinical setting increases the likelihood of interactions among mAb molecules, diluent, and plasma components, which may adversely affect product safety and efficacy. Avastin® (bevacizumab) and Herceptin® (trastuzumab), but not Remicade® (infliximab), were shown to undergo rapid aggregation upon dilution into 5% dextrose when mixed with human plasma in vitro; however, the biochemical pathways leading to the aggregation were not clearly defined. Here, we show that dextrose-mediated aggregation of Avastin or Herceptin in plasma involves isoelectric precipitation of complement proteins. Using mass spectrometry, we found that dextrose-induced insoluble aggregates were composed of mAb itself and multiple abundant plasma proteins, namely complement proteins C3, C4, factor H, fibronectin, and apolipoprotein. These plasma proteins, which are characterized by an isoelectronic point of 5.5-6.7, lost solubility at the resulting pH in the mixture with formulated Avastin (pH 6.2) and Herceptin (pH 6.0). Notably, switching formulation buffers for Avastin (pH 6.2) and Remicade (pH 7.2) reversed their aggregation profiles. Avastin formed little, if any, insoluble aggregates in dextrose-plasma upon raising the buffer pH to 7.2 or above. Furthermore, dextrose induced pH-dependent precipitation of plasma proteins, with massive insoluble aggregates being detected at pH 6.5-6.8. These data show that isoelectric precipitation of complement proteins is a prerequisite of dextrose-induced aggregation of mAb in human plasma. This finding highlights the importance of assessing the compatibility of a therapeutic mAb with diluent and human plasma during product development. PMID:26338058

  15. Dextrose-mediated aggregation of therapeutic monoclonal antibodies in human plasma: Implication of isoelectric precipitation of complement proteins.

    Science.gov (United States)

    Luo, Shen; Zhang, Baolin

    2015-01-01

    Many therapeutic monoclonal antibodies (mAbs) are clinically administered through intravenous infusion after mixing with a diluent, e.g., saline, 5% dextrose. Such a clinical setting increases the likelihood of interactions among mAb molecules, diluent, and plasma components, which may adversely affect product safety and efficacy. Avastin® (bevacizumab) and Herceptin® (trastuzumab), but not Remicade® (infliximab), were shown to undergo rapid aggregation upon dilution into 5% dextrose when mixed with human plasma in vitro; however, the biochemical pathways leading to the aggregation were not clearly defined. Here, we show that dextrose-mediated aggregation of Avastin or Herceptin in plasma involves isoelectric precipitation of complement proteins. Using mass spectrometry, we found that dextrose-induced insoluble aggregates were composed of mAb itself and multiple abundant plasma proteins, namely complement proteins C3, C4, factor H, fibronectin, and apolipoprotein. These plasma proteins, which are characterized by an isoelectronic point of 5.5-6.7, lost solubility at the resulting pH in the mixture with formulated Avastin (pH 6.2) and Herceptin (pH 6.0). Notably, switching formulation buffers for Avastin (pH 6.2) and Remicade (pH 7.2) reversed their aggregation profiles. Avastin formed little, if any, insoluble aggregates in dextrose-plasma upon raising the buffer pH to 7.2 or above. Furthermore, dextrose induced pH-dependent precipitation of plasma proteins, with massive insoluble aggregates being detected at pH 6.5-6.8. These data show that isoelectric precipitation of complement proteins is a prerequisite of dextrose-induced aggregation of mAb in human plasma. This finding highlights the importance of assessing the compatibility of a therapeutic mAb with diluent and human plasma during product development.

  16. γδ T cell-mediated antibody-dependent cellular cytotoxicity with CD19 antibodies assessed by an impedance-based label-free real-time cytotoxicity assay

    Directory of Open Access Journals (Sweden)

    Ursula Jördis Eva Seidel

    2014-12-01

    Full Text Available γδ T cells are not MHC restricted, elicit cytotoxicity against various malignancies, are present in early post-transplant phases in novel stem cell transplantation (SCT strategies and have been shown to mediate antibody-dependent cellular cytotoxicity (ADCC with monoclonal antibodies (mAbs. These features make γδ T cells promising effector cells for antibody-based immunotherapy in pediatric patients with B-lineage acute lymphoblastic leukemia (ALL. To evaluate combination of human γδ T cells with CD19 antibodies for immunotherapy of B-lineage ALL, γδ T cells were expanded after a GMP-compliant protocol and ADCC of both primary and expanded γδ T cells with an Fc optimized CD19 antibody (4G7SDIE and a bispecific antibody with the specificities CD19 and CD16 (N19-C16 was evaluated in CD107a degranulation assays and intracellular cytokine staining (ICS. CD107a, TNF-α and IFN-γ expression of primary γδ T cells were significantly increased and correlated with CD16-expression of γδ T cells. γδ T cells highly expressed CD107a after expansion and no further increased expression by 4G7SDIE and N19-C16 was measured. Cytotoxicity of purified expanded γδ T cells targeting CD19-expressing cells was assessed in both europium-TDA release and in an impedance-based label-free method (using the xCELLigence system measuring γδ T cell lysis in real-time. Albeit in the 2 h end-point europium-TDA release assay no increased lysis was observed, in real-time xCELLigence assays both significant antibody-independent cytotoxicity and ADCC of γδ T cells were observed. The xCELLigence system outperformed the end-point europium-TDA release assay in sensitivity and allows drawing of conclusions to lysis kinetics of γδ T cells over prolonged periods of time periods. Combination of CD19 antibodies with primary as well as expanded γδ T cells exhibits an promising approach, which may enhance clinical outcome of patients with pediatric B-lineage ALL and

  17. γδ T Cell-Mediated Antibody-Dependent Cellular Cytotoxicity with CD19 Antibodies Assessed by an Impedance-Based Label-Free Real-Time Cytotoxicity Assay.

    Science.gov (United States)

    Seidel, Ursula Jördis Eva; Vogt, Fabian; Grosse-Hovest, Ludger; Jung, Gundram; Handgretinger, Rupert; Lang, Peter

    2014-01-01

    γδ T cells are not MHC restricted, elicit cytotoxicity against various malignancies, are present in early post-transplant phases in novel stem cell transplantation strategies and have been shown to mediate antibody-dependent cellular cytotoxicity (ADCC) with monoclonal antibodies (mAbs). These features make γδ T cells promising effector cells for antibody-based immunotherapy in pediatric patients with B-lineage acute lymphoblastic leukemia (ALL). To evaluate combination of human γδ T cells with CD19 antibodies for immunotherapy of B-lineage ALL, γδ T cells were expanded after a GMP-compliant protocol and ADCC of both primary and expanded γδ T cells with an Fc-optimized CD19 antibody (4G7SDIE) and a bi-specific antibody with the specificities CD19 and CD16 (N19-C16) was evaluated in CD107a-degranulation assays and intracellular cytokine staining. CD107a, TNFα, and IFNγ expression of primary γδ T cells were significantly increased and correlated with CD16-expression of γδ T cells. γδ T cells highly expressed CD107a after expansion and no further increased expression by 4G7SDIE and N19-C16 was measured. Cytotoxicity of purified expanded γδ T cells targeting CD19-expressing cells was assessed in both europium-TDA release and in an impedance-based label-free method (using the xCELLigence system) measuring γδ T cell lysis in real-time. Albeit in the 2 h end-point europium-TDA release assay no increased lysis was observed, in real-time xCELLigence assays both significant antibody-independent cytotoxicity and ADCC of γδ T cells were observed. The xCELLigence system outperformed the end-point europium-TDA release assay in sensitivity and allows drawing of conclusions to lysis kinetics of γδ T cells over prolonged periods of time periods. Combination of CD19 antibodies with primary as well as expanded γδ T cells exhibits a promising approach, which may enhance clinical outcome of patients with pediatric B-lineage ALL and requires clinical

  18. The impact of pretransplant donor-specific antibodies on graft outcome in renal transplantation: a six-year follow-up study

    Directory of Open Access Journals (Sweden)

    Elias David-Neto

    2012-01-01

    Full Text Available OBJECTIVE: The significance of pretransplant, donor-specific antibodies on long-term patient outcomes is a subject of debate. This study evaluated the impact and the presence or absence of donor-specific antibodies after kidney transplantation on short- and long-term graft outcomes. METHODS: We analyzed the frequency and dynamics of pretransplant donor-specific antibodies following renal transplantation from a randomized trial that was conducted from 2002 to 2004 and correlated these findings with patient outcomes through 2009. Transplants were performed against a complement-dependent T- and B-negative crossmatch. Pre- and posttransplant sera were available from 94 of the 118 patients (80%. Antibodies were detected using a solid-phase (LuminexH, single-bead assay, and all tests were performed simultaneously. RESULTS: Sixteen patients exhibited pretransplant donor-specific antibodies, but only 3 of these patients (19% developed antibody-mediated rejection and 2 of them experienced early graft losses. Excluding these 2 losses, 6 of 14 patients exhibited donor-specific antibodies at the final follow-up exam, whereas 8 of these patients (57% exhibited complete clearance of the donor-specific antibodies. Five other patients developed ''de novo'' posttransplant donor-specific antibodies. Death-censored graft survival was similar in patients with pretransplant donor-specific and non-donor-specific antibodies after a mean follow-up period of 70 months. CONCLUSION: Pretransplant donor-specific antibodies with a negative complement-dependent cytotoxicity crossmatch are associated with a risk for the development of antibody-mediated rejection, although survival rates are similar when patients transpose the first months after receiving the graft. Our data also suggest that early posttransplant donor-specific antibody monitoring should increase knowledge of antibody dynamics and their impact on long-term graft outcome.

  19. On the Meaning of Affinity Limits in B-Cell Epitope Prediction for Antipeptide Antibody-Mediated Immunity

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    Salvador Eugenio C. Caoili

    2012-01-01

    Full Text Available B-cell epitope prediction aims to aid the design of peptide-based immunogens (e.g., vaccines for eliciting antipeptide antibodies that protect against disease, but such antibodies fail to confer protection and even promote disease if they bind with low affinity. Hence, the Immune Epitope Database (IEDB was searched to obtain published thermodynamic and kinetic data on binding interactions of antipeptide antibodies. The data suggest that the affinity of the antibodies for their immunizing peptides appears to be limited in a manner consistent with previously proposed kinetic constraints on affinity maturation in vivo and that cross-reaction of the antibodies with proteins tends to occur with lower affinity than the corresponding reaction of the antibodies with their immunizing peptides. These observations better inform B-cell epitope prediction to avoid overestimating the affinity for both active and passive immunization; whereas active immunization is subject to limitations of affinity maturation in vivo and of the capacity to accumulate endogenous antibodies, passive immunization may transcend such limitations, possibly with the aid of artificial affinity-selection processes and of protein engineering. Additionally, protein disorder warrants further investigation as a possible supplementary criterion for B-cell epitope prediction, where such disorder obviates thermodynamically unfavorable protein structural adjustments in cross-reactions between antipeptide antibodies and proteins.

  20. Increased infectivity in human cells and resistance to antibody-mediated neutralization by truncation of the SIV gp41 cytoplasmic tail.

    Science.gov (United States)

    Kuwata, Takeo; Kaori, Takaki; Enomoto, Ikumi; Yoshimura, Kazuhisa; Matsushita, Shuzo

    2013-01-01

    The role of antibodies in protecting the host from human immunodeficiency virus type 1 (HIV-1) infection is of considerable interest, particularly because the RV144 trial results suggest that antibodies contribute to protection. Although infection of non-human primates with simian immunodeficiency virus (SIV) is commonly used as an animal model of HIV-1 infection, the viral epitopes that elicit potent and broad neutralizing antibodies to SIV have not been identified. We isolated a monoclonal antibody (MAb) B404 that potently and broadly neutralizes various SIV strains. B404 targets a conformational epitope comprising the V3 and V4 loops of Env that intensely exposed when Env binds CD4. B404-resistant variants were obtained by passaging viruses in the presence of increasing concentration of B404 in PM1/CCR5 cells. Genetic analysis revealed that the Q733stop mutation, which truncates the cytoplasmic tail of gp41, was the first major substitution in Env during passage. The maximal inhibition by B404 and other MAbs were significantly decreased against a recombinant virus with a gp41 truncation compared with the parental SIVmac316. This indicates that the gp41 truncation was associated with resistance to antibody-mediated neutralization. The infectivities of the recombinant virus with the gp41 truncation were 7,900-, 1,000-, and 140-fold higher than those of SIVmac316 in PM1, PM1/CCR5, and TZM-bl cells, respectively. Immunoblotting analysis revealed that the gp41 truncation enhanced the incorporation of Env into virions. The effect of the gp41 truncation on infectivity was not obvious in the HSC-F macaque cell line, although the resistance of viruses harboring the gp41 truncation to neutralization was maintained. These results suggest that viruses with a truncated gp41 cytoplasmic tail were selected by increased infectivity in human cells and by acquiring resistance to neutralizing antibody. PMID:23717307

  1. Increased infectivity in human cells and resistance to antibody-mediated neutralization by truncation of the SIV gp41 cytoplasmic tail

    Directory of Open Access Journals (Sweden)

    Takeo eKuwata

    2013-05-01

    Full Text Available The role of antibodies in protecting the host from human immunodeficiency virus type 1 (HIV-1 infection is of considerable interest, particularly because the RV144 trial results suggest that antibodies contribute to protection. Although infection of nonhuman primates with simian immunodeficiency virus (SIV is commonly used as an animal model of HIV-1 infection, the viral epitopes that elicit potent and broad neutralizing antibodies to SIV have not been identified. We isolated a monoclonal antibody (MAb B404 that potently and broadly neutralizes various SIV strains. B404 targets a conformational epitope comprising the V3 and V4 loops of Env that intensely exposed when Env binds CD4. B404-resistant variants were obtained by passaging viruses in the presence of increasing concentration of B404 in PM1/CCR5 cells. Genetic analysis revealed that the Q733stop mutation, which truncates the cytoplasmic tail of gp41, was the first major substitution in Env during passage. The maximal inhibition by B404 and other MAbs were significantly decreased against a recombinant virus with a gp41 truncation compared with the parental SIVmac316. This indicates that the gp41 truncation was associated with resistance to antibody-mediated neutralization. The infectivities of the recombinant virus with the gp41 truncation were 7900-fold, 1000-fold, and 140-fold higher than those of SIVmac316 in PM1, PM1/CCR5, and TZM-bl cells, respectively. Immunoblotting analysis revealed that the gp41 truncation enhanced the incorporation of Env into virions. The effect of the gp41 truncation on infectivity was not obvious in the HSC-F macaque cell line, although the resistance of viruses harboring the gp41 truncation to neutralization was maintained. These results suggest that viruses with a truncated gp41 cytoplasmic tail were selected by increased infectivity in human cells and by acquiring resistance to neutralizing antibody.

  2. Immobilized surfactant-nanotube complexes support selectin-mediated capture of viable circulating tumor cells in the absence of capture antibodies.

    Science.gov (United States)

    Mitchell, Michael J; Castellanos, Carlos A; King, Michael R

    2015-10-01

    The metastatic spread of tumor cells from the primary site to anatomically distant organs leads to a poor patient prognosis. Increasing evidence has linked adhesive interactions between circulating tumor cells (CTCs) and endothelial cells to metastatic dissemination. Microscale biomimetic flow devices hold promise as a diagnostic tool to isolate CTCs and develop metastatic therapies, utilizing E-selectin (ES) to trigger the initial rolling adhesion of tumor cells under flow. To trigger firm adhesion and capture under flow, such devices also typically require antibodies against biomarkers thought to be expressed on CTCs. This approach is challenged by the fact that CTCs are now known to exhibit heterogeneous expression of conventional biomarkers. Here, we describe surfactant-nanotube complexes to enhance ES-mediated capture and isolation of tumor cells without the use of capture antibodies. While the majority of tumor cells exhibited weaker rolling adhesion on halloysite nanotubes (HNT) coated with ES, HNT functionalization with the sodium dodecanoate (NaL) surfactant induced a switch to firm cellular adhesion under flow. Conversely, surfactant-nanotube complexes significantly reduced the number of primary human leukocytes captured via ES-mediated adhesion under flow. The switch in tumor cell adhesion was exploited to capture and isolate tumor cells in the absence of EpCAM antibodies, commonly utilized as the gold standard for CTC isolation. Additionally, HNT-NaL complexes were shown to capture tumor cells with low to negligible EpCAM expression, that are not efficiently captured using conventional approaches.

  3. Chronic allograft rejection: A significant hurdle to transplant success

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    Malgorzata Kloc

    2014-01-01

    Full Text Available The state-of-the-art immunosuppression drugs do not ensure indefinite transplant survival, and most transplants are continuously lost to chronic rejection even years posttransplantation. This form of rejection is responsible for long-term failure of transplanted organs. The mechanisms involved in development of chronic rejection are not well-understood. One of the main features of chronic rejection is progressive luminal narrowing of graft vessels, which results in compromised blood flow, ischemia, cell death, and finally graft failure. All the existing immunosuppressive regimens are targeting acute rejection, and at present there is no available therapy for prevention of chronic rejection. Chronic rejection involves two major, but interrelated responses: The first is the host immune response against the transplant mediated primarily by alloreactive T and B cells, and the second is injury and repair of the graft (vasculopathy of graft vessels. Here we focus on recent advances in understanding the cellular and molecular aspects of chronic transplant vasculopathy and function of macrophages, topics pivotal for development of novel antichronic rejection therapies.

  4. Control of culture environment for improved polyethylenimine-mediated transient production of recombinant monoclonal antibodies by CHO cells.

    Science.gov (United States)

    Galbraith, Douglas J; Tait, Andrew S; Racher, Andrew J; Birch, John R; James, David C

    2006-01-01

    In this study we describe optimization of polyethylenimine (PEI)-mediated transient production of recombinant protein by CHO cells by facile manipulation of a chemically defined culture environment to limit accumulation of nonproductive cell biomass, increase the duration of recombinant protein production from transfected plasmid DNA, and increase cell-specific production. The optimal conditions for transient transfection of suspension-adapted CHO cells using branched, 25 kDa PEI as a gene delivery vehicle were experimentally determined by production of secreted alkaline phosphatase reporter in static cultures and recombinant IgG4 monoclonal antibody (Mab) production in agitated shake flask cultures to be a DNA concentration of 1.25 microg 10(6) cells(-1) mL(-1) at a PEI nitrogen:DNA phosphate ratio of 20:1. These conditions represented the optimal compromise between PEI cytotoxicity and product yield with most efficient recombinant DNA utilization. Separately, both addition of recombinant insulin-like growth factor (LR3-IGF) and a reduction in culture temperature to 32 degrees C were found to increase product titer 2- and 3-fold, respectively. However, mild hypothermia and LR3-IGF acted synergistically to increase product titer 11-fold. Although increased product titer in the presence of LR3-IGF alone was solely a consequence of increased culture duration, a reduction in culture temperature post-transfection increased both the integral of viable cell concentration (IVC) and cell-specific Mab production rate. For cultures maintained at 32 degrees C in the presence of LR3-IGF, IVC and qMab were increased 4- and 2.5-fold, respectively. To further increase product yield from transfected DNA, the duration of transgene expression in cell populations maintained at 32 degrees C in the presence of LR3-IGF was doubled by periodic resuspension of transfected cells in fresh media, leading to a 3-fold increase in accumulated Mab titer from approximately 13 to approximately 39

  5. Effect of Low Molecular Weight Heparins (LMWHs on antiphospholipid Antibodies (aPL-mediated inhibition of endometrial angiogenesis.

    Directory of Open Access Journals (Sweden)

    Silvia D'Ippolito

    Full Text Available Antiphospholipid syndrome (APS is an autoimmune disorder characterized by vascular thrombosis and/or pregnancy morbidity in the presence of circulating antiphospholipid antibodies (aPL. Different pathogenic mechanisms for aPL-mediated pregnancy failure have been proposed. In particular a direct effect of aPL on both maternal and fetal side of the placental tissue has been reported, since their reactivity with β2-glycoprotein I (β2GPI makes them adhere to trophoblast and human endometrial endothelial cell (HEEC membranes. β2GPI can be recognized by aPL that, once bound, interfere with both trophoblast functions and with the HEEC differentiation.APS patients can be successfully treated with Low Molecular Weight Heparin (LMWH. Recent reports suggest that LMWH acts through mechanisms alternative to its well known anticoagulant effect, because of its ability to bind β2GPI. In our previous studies, we showed that LMWH is able to reduce the aPL binding to trophoblasts and restore cell invasiveness and differentiation. So far, however, no study has described its effects on endometrial angiogenesis.The aim of our research was to evaluate whether two LMWHs, tinzaparin and enoxaparin, have an effect on the aPL-inhibited endometrial angiogenesis. This prompted us to investigate: (i in vitro HEEC angiogenesis through a Matrigel assay; (ii VEGF secretion by ELISA; (iii matrix metalloproteinase-2 (MMP-2 activity by gelatin zymography; (iv Nuclear Factor-κB (NF-κB DNA binding activity by colorimetric assay; (v STAT-3 activation by a sandwich-ELISA kit. Furthermore, using an in vivo murine model we investigated the LMWHs effects on angiogenesis.We demonstrated that the addition of LMWHs prevents aPL-inhibited HEEC angiogenesis, both in vitro and in vivo, and is able to restore the aPL inhibited NF-κB and/or STAT-3 activity, the VEGF secretion and the MMPs activity.The demonstration of a beneficial role for LMWHs on the aPL-inhibited HEEC angiogenesis

  6. Rejected by peers-attracted to antisocial media content: rejection-based anger impairs moral judgment among adolescents.

    Science.gov (United States)

    Plaisier, Xanthe S; Konijn, Elly A

    2013-06-01

    Adolescence is an important developmental stage during which both peers and the media have a strong influence. Both peer rejection and the use of morally adverse media are associated with negative developmental outcomes. This study examines processes by which peer rejection might drive adolescents to select antisocial media content by tying together developmental research on peer rejection and research on media effects. Assumed underlying mechanisms are rejection-based anger and frustration and the adolescent's moral judgment. A between-participants experimental design manipulated peer rejection versus acceptance in adolescents (Mage = 13.88 years; N = 74) and young adults (Mage = 21.37 years; N = 75), applying the Cyberball paradigm. Measures included the State Anger Inventory (STAXI) to assess feelings of rejection and the newly devised Media, Morals, and Youth Questionnaire (MMaYQue) to assess media preferences and moral judgment of media content. Using bootstrapping analyses, a double mediation was established: Higher levels of state anger in peer-rejected adolescents induced more tolerable moral judgments of antisocial media content, subsequently instigating a preference for antisocial media content. In contrast, the young adult sample showed no relations between peer rejection and antisocial media preference. Results are discussed within a downward spiral framework of combined peer and media influences. PMID:22799588

  7. Immune-mediated steroid-responsive epileptic spasms and epileptic encephalopathy associated with VGKC-complex antibodies.

    Science.gov (United States)

    Suleiman, Jehan; Brenner, Tanja; Gill, Deepak; Troedson, Christopher; Sinclair, Adriane J; Brilot, Fabienne; Vincent, Angela; Lang, Bethan; Dale, Russell C

    2011-11-01

    Autoantibodies that bind to voltage-gated potassium-channel complex proteins (VGKC-complex antibodies) occur frequently in adults with limbic encephalitis presenting with cognitive impairment and seizures. Recently, VGKC-complex antibodies have been described in a few children with limbic encephalitis, and children with unexplained encephalitis presenting with status epilepticus. We report a case of infantile-onset epileptic spasms and developmental delay compatible with epileptic encephalopathy. Our patient was a female infant, aged 4 months at presentation. She had evidence of immune activation in the central nervous system with elevated cerebrospinal fluid neopterin and mirrored oligoclonal bands, which prompted testing for autoantibodies. VGKC-complex antibodies were elevated (201 pmol/L, normalVGKC-complex antibodies might represent a marker of immune therapy responsiveness in a subgroup of patients with infantile epileptic encephalopathy.

  8. Conserved natural IgM antibodies mediate innate and adaptive immunity against the opportunistic fungus Pneumocystis murina.

    Science.gov (United States)

    Rapaka, Rekha R; Ricks, David M; Alcorn, John F; Chen, Kong; Khader, Shabaana A; Zheng, Mingquan; Plevy, Scott; Bengtén, Eva; Kolls, Jay K

    2010-12-20

    Host defense against opportunistic fungi requires coordination between innate and adaptive immunity for resolution of infection. Antibodies generated in mice vaccinated with the fungus Pneumocystis prevent growth of Pneumocystis organisms within the lungs, but the mechanisms whereby antibodies enhance antifungal host defense are poorly defined. Nearly all species of fungi contain the conserved carbohydrates β-glucan and chitin within their cell walls, which may be targets of innate and adaptive immunity. In this study, we show that natural IgM antibodies targeting these fungal cell wall carbohydrates are conserved across many species, including fish and mammals. Natural antibodies bind fungal organisms and enhance host defense against Pneumocystis in early stages of infection. IgM antibodies influence recognition of fungal antigen by dendritic cells, increasing their migration to draining pulmonary lymph nodes. IgM antibodies are required for adaptive T helper type 2 (Th2) and Th17 cell differentiation and guide B cell isotype class-switch recombination during host defense against Pneumocystis. These experiments suggest a novel role for the IgM isotype in shaping the earliest steps in recognition and clearance of this fungus. We outline a mechanism whereby serum IgM, containing ancient specificities against conserved fungal antigens, bridges innate and adaptive immunity against fungal organisms.

  9. Cells of the J774 macrophage cell line are primed for antibody-dependent cell-mediated cytotoxicity following exposure to γ-irradiation

    International Nuclear Information System (INIS)

    Activation of macrophages (M phi) for host defense against tumor cells follows a sequence of priming events followed by an initiating stimulus that results in production and release of cytotoxic molecules that mediate target cell killing. The authors have developed a model to study specific macrophage cytotoxicity in vitro utilizing a cultured murine M phi cell line, J774. Specific cytotoxicity of cultured human gastrointestinal tumor cells is achieved in the presence of murine IgG2a monoclonal antibody (mAb) 17-1-A. The ability of these cells to mediate antibody-dependent cell-mediated cytotoxicity (ADCC) is greatly enhanced following gamma-irradiation. ADCC can be demonstrated at mAb 17-1-A concentrations greater than or equal to 1 microgram/ml and effector/target cell ratios greater than or equal to 2. Exposure to doses greater than or equal to 10 Gy of gamma-irradiation increases ADCC threefold. Varying the duration from J774 M phi exposure to γ-irradiation until addition of antibody-coated target cells showed that the primed state for ADCC is stable for at least 8 days but approximately 24 hr is required for complete development of the primed state. mAb-dependent target cell death begins 8 hr after addition of mAb and labeled target cells to primed effector cells and is complete by 24 hr. Incubation of unirradiated J774 M phi effector cells with recombinant murine interferon-γ (rmIFN-γ) also results in enhanced ADCC, but the extent of target cell killing achieved is less than that following priming by γ-irradiation. Concomitant priming of γ-irradiated J774 M phi with rmIFN-γ increases the extent of ADCC. Further study of irradiated J774 cells may elucidate the molecular pathways utilized by M phi for achieving and maintaining the primed state for ADCC

  10. MORPHOLOGICAL AND IMMUNOHISTOCHEMICAL MANIFESTATIONS OF DIFFERENT VARIANTS OF ACUTE KIDNEY ALLOGRAFT REJECTION

    Directory of Open Access Journals (Sweden)

    A.V Trailin

    2009-01-01

    Full Text Available The aim of this study was morphological characteristics of peculiar properties of acute T-cells- (ATMR and antibody-mediated kidney allograft rejection (AAMR. Histological slices of kidney allograft biopsies were examined after coloration by routine methods and immunohistochemical proceeding for C4d, CD45R0 T-lymphocytes antigen and CD68 macrophages antigen. We’ve determined that the key features of ATMR are: increasing of T-lymphocytes interstitial infi ltration with the same level of macrophages infi ltration comparing with implantation biopsies, mild mononuclear glomerulitis and capillaritis; tubulitis. Morphological traits of AAMR are neutrophilic and T-lymphocytes glomerulitis, diffuse capillaritis, capillaries dilatation and margination of mononuclear cells with admixture of neutrophils, macrophagal interstitial infi ltration under semiquantitative evaluation, as well as, more pronounced, than in ATMR, T-lymphoctes and macrophages interstitial infi ltration under quantitative evaluation.

  11. Structure and function of broadly reactive antibody PG16 reveal an H3 subdomain that mediates potent neutralization of HIV-1

    Energy Technology Data Exchange (ETDEWEB)

    Pejchal, Robert; Walker, Laura M.; Stanfield, Robyn L.; Phogat, Sanjay K.; Koff, Wayne C.; Poignard, Pascal; Burton, Dennis R.; Wilson, Ian A. (Scripps); (IAVI)

    2010-11-15

    Development of an effective vaccine against HIV-1 will likely require elicitation of broad and potent neutralizing antibodies against the trimeric surface envelope glycoprotein (Env). Monoclonal antibodies (mAbs) PG9 and PG16 neutralize {approx}80% of HIV-1 isolates across all clades with extraordinary potency and target novel epitopes preferentially expressed on Env trimers. As these neutralization properties are ideal for a vaccine-elicited antibody response to HIV-1, their structural basis was investigated. The crystal structure of the antigen-binding fragment (Fab) of PG16 at 2.5 {angstrom} resolution revealed its unusually long, 28-residue, complementarity determining region (CDR) H3 forms a unique, stable subdomain that towers above the antibody surface. A 7-residue 'specificity loop' on the 'hammerhead' subdomain was identified that, when transplanted from PG16 to PG9 and vice versa, accounted for differences in the fine specificity and neutralization of these two mAbs. The PG16 electron density maps also revealed that a CDR H3 tyrosine was sulfated, which was confirmed for both PG9 (doubly) and PG16 (singly) by mass spectral analysis. We further showed that tyrosine sulfation plays a role in binding and neutralization. An N-linked glycan modification is observed in the variable light chain, but not required for antigen recognition. Further, the crystal structure of the PG9 light chain at 3.0 {angstrom} facilitated homology modeling to support the presence of these unusual features in PG9. Thus, PG9 and PG16 use unique structural features to mediate potent neutralization of HIV-1 that may be of utility in antibody engineering and for high-affinity recognition of a variety of therapeutic targets.

  12. The effect of daily co-trimoxazole prophylaxis on natural development of antibody-mediated immunity against P. falciparum malaria infection in HIV-exposed uninfected Malawian children.

    Directory of Open Access Journals (Sweden)

    Herbert Longwe

    Full Text Available Co-trimoxazole prophylaxis, currently recommended in HIV-exposed, uninfected (HEU children as protection against opportunistic infections, also has some anti-malarial efficacy. We determined whether daily co-trimoxazole prophylaxis affects the natural development of antibody-mediated immunity to blood-stage Plasmodium falciparum malaria infection.Using an enzyme-linked immunosorbent assay, we measured antibodies to 8 Plasmodium falciparum antigens (AMA-1, MSP-119, MSP-3, PfSE, EBA-175RII, GLURP R0, GLURP R2 and CSP in serum samples from 33 HEU children and 31 HIV-unexposed, uninfected (HUU children, collected at 6, 12 and 18 months of age.Compared to HIV-uninfected children, HEU children had significantly lower levels of specific IgG against AMA-1 at 6 months (p = 0.001, MSP-119 at 12 months (p = 0.041 and PfSE at 6 months (p = 0.038, 12 months (p = 0.0012 and 18 months (p = 0.0097. No differences in the IgG antibody responses against the rest of the antigens were observed between the two groups at all time points. The breadth of specificity of IgG response was reduced in HEU children compared to HUU children during the follow up period.Co-trimoxazole prophylaxis seems to reduce IgG antibody responses to P. falciparum blood stage antigens, which could be as a result of a reduction in exposure of those children under this regime. Although antibody responses were regarded as markers of exposure in this study, further studies are required to establish whether these responses are correlated in any way to clinical immunity to malaria.

  13. Rejection sampling in demand systems

    OpenAIRE

    Ley, Eduardo; Mark F.J. Steel

    1992-01-01

    We illustrate the method of rejection sampling in a Bayesian application of a new approach toı estimating Demand Systems. This approach, suggested by Varian (1990), is based on a generalization of Afriat's (1967) efficiency index. Rejection sampling is applied to the prior-to-posterior mapping enabling us to obtain posterior results in a nonstandard model.

  14. Radionuclide diagnosis of allograft rejection

    Energy Technology Data Exchange (ETDEWEB)

    George, E.A.

    1982-10-01

    Interaction with one or more anatomical and physiopathological characteristics of the rejecting renal allograft is suggested by those radioagents utilized specifically for the diagnosis of allograft rejection. Rejection, the most common cause of declining allograft function, is frequently mimicked clinically or masked by other immediate or long term post transplant complications. Understanding of the anatomical pathological features and kinetics of rejection and their modification by immunosuppressive maintenance and therapy are important for the proper clinical utilization of these radioagents. Furthermore, in selecting these radionuclides, one has to consider the comparative availability, preparatory and procedural simplicity, acquisition and display techniques and the possibility of timely report. The clinical utilities of radiofibrinogen, /sup 99m/Tc sulfur colloid and /sup 67/Ga in the diagnosis of allograft rejection have been evaluated to a variable extent in the past. The potential usefulness of the recently developed preparations of /sup 111/In labeled autologous leukocytes and platelets are presently under investigation.

  15. HLA Class II Antibody Activation of Endothelial Cells Promotes Th17 and Disrupts Regulatory T Lymphocyte Expansion.

    Science.gov (United States)

    Lion, J; Taflin, C; Cross, A R; Robledo-Sarmiento, M; Mariotto, E; Savenay, A; Carmagnat, M; Suberbielle, C; Charron, D; Haziot, A; Glotz, D; Mooney, N

    2016-05-01

    Kidney transplantation is the most successful treatment option for patients with end-stage renal disease, and chronic antibody-mediated rejection is the principal cause of allograft loss. Predictive factors for chronic rejection include high levels of HLA alloantibodies (particularly HLA class II) and activation of graft endothelial cells (ECs). The mechanistic basis for this association is unresolved. We used an experimental model of HLA-DR antibody stimulation of microvascular ECs to examine the mechanisms underlying the association between HLA class II antibodies, EC activation and allograft damage. Activation of ECs with the F(Ab')2 fragment of HLA-DR antibody led to phosphorylation of Akt, ERK and MEK and increased IL-6 production by ECs cocultured with allogeneic peripheral blood mononuclear cells (PBMCs) in an Akt-dependent manner. We previously showed that HLA-DR-expressing ECs induce polarization of Th17 and FoxP3(bright) regulatory T cell (Treg) subsets. Preactivation of ECs with anti-HLA-DR antibody redirected EC allogenicity toward a proinflammatory response by decreasing amplification of functional Treg and by further increasing IL-6-dependent Th17 expansion. Alloimmunized patient serum containing relevant HLA-DR alloantibodies selectively bound and increased EC secretion of IL-6 in cocultures with PBMCs. These data contribute to understanding of potential mechanisms of antibody-mediated endothelial damage independent of complement activation and FcR-expressing effector cells. PMID:26614587

  16. Molecular determinants of dengue virus 2 envelope protein important for virus entry in FcγRIIA-mediated antibody-dependent enhancement of infection

    International Nuclear Information System (INIS)

    Antibody-dependent enhancement (ADE) of infection may cause severe illness in patients suffering a secondary infection by a heterologous dengue virus (DENV) serotype. During ADE of infection, cross-reactive non- or poorly-neutralizing antibodies form infectious virus-Ab complexes with the newly infecting serotype and enhance virus infection by binding to the Fcγ receptors (FcγR) on FcγR-bearing cells. In this study, we determined that molecular determinants of DENV2 envelope protein critical for virus entry during non-ADE infection are also required for ADE infection mediated by FcγRIIA, and binding of virus-Ab complexes with FcγRIIA alone is not sufficient for ADE of infection. The FcγRIIA mainly plays an auxiliary role in concentrating the virus–Ab complex to the cell surface, and other primary cellular receptors are required for virus entry. Understanding the viral entry pathway in ADE of DENV infection will greatly facilitate rational designs of anti-viral therapeutics against severe dengue disease associated with ADE. - Highlights: • KKK305/307/310 in DENV2 E-DIII is critical for virus attachment in ADE and non-ADE infection. • Binding of DENV2–Ab complex with FcγRII alone is not sufficient for virus entry in ADE infection. • Other primary receptors were required for DENV2 internalization during FcγRII–mediated ADE. • G104 and L135 of DENV2 E are critical for virus-mediated membrane fusion. • DENV2 virus-mediated membrane fusion is required for both ADE and non-ADE infection

  17. Molecular determinants of dengue virus 2 envelope protein important for virus entry in FcγRIIA-mediated antibody-dependent enhancement of infection

    Energy Technology Data Exchange (ETDEWEB)

    Chotiwan, Nunya; Roehrig, John T. [Arboviral Diseases Branch, Division of Vector-Borne Disease, Centers for Disease Control and Prevention, Fort Collins, CO 80521 (United States); Schlesinger, Jacob J. [Department of Medicine, University of Rochester, Rochester, NY 14642 (United States); Blair, Carol D. [Arthropod-borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523 (United States); Huang, Claire Y.-H., E-mail: yxh0@cdc.gov [Arboviral Diseases Branch, Division of Vector-Borne Disease, Centers for Disease Control and Prevention, Fort Collins, CO 80521 (United States)

    2014-05-15

    Antibody-dependent enhancement (ADE) of infection may cause severe illness in patients suffering a secondary infection by a heterologous dengue virus (DENV) serotype. During ADE of infection, cross-reactive non- or poorly-neutralizing antibodies form infectious virus-Ab complexes with the newly infecting serotype and enhance virus infection by binding to the Fcγ receptors (FcγR) on FcγR-bearing cells. In this study, we determined that molecular determinants of DENV2 envelope protein critical for virus entry during non-ADE infection are also required for ADE infection mediated by FcγRIIA, and binding of virus-Ab complexes with FcγRIIA alone is not sufficient for ADE of infection. The FcγRIIA mainly plays an auxiliary role in concentrating the virus–Ab complex to the cell surface, and other primary cellular receptors are required for virus entry. Understanding the viral entry pathway in ADE of DENV infection will greatly facilitate rational designs of anti-viral therapeutics against severe dengue disease associated with ADE. - Highlights: • KKK305/307/310 in DENV2 E-DIII is critical for virus attachment in ADE and non-ADE infection. • Binding of DENV2–Ab complex with FcγRII alone is not sufficient for virus entry in ADE infection. • Other primary receptors were required for DENV2 internalization during FcγRII–mediated ADE. • G104 and L135 of DENV2 E are critical for virus-mediated membrane fusion. • DENV2 virus-mediated membrane fusion is required for both ADE and non-ADE infection.

  18. A novel noninvasive method to detect rejection after heart transplantation

    Directory of Open Access Journals (Sweden)

    Jun Hu

    2012-12-01

    Full Text Available Prompt and accurate detection of rejection prior to pathological changes after organ transplantation is vital for monitoring rejections. Although biopsy remains the current gold standard for rejection diagnosis, it is an invasive method and cannot be repeated daily. Thus, noninvasive monitoring methods are needed. In this study, by introducing an IL-2 neutralizing monoclonal antibody (IL-2 N-mAb and immunosuppressants into the culture with the presence of specific stimulators and activated lymphocytes, an activated lymphocyte-specific assay (ALSA system was established to detect the specific activated lymphocytes. This assay demonstrated that the suppression in the ALSA test was closely related to the existence of specific activated lymphocytes. The ALSA test was applied to 47 heart graft recipients and the proliferation of activated lymphocytes from all rejection recipients proven by endomyocardial biopsies was found to be inhibited by spleen cells from the corresponding donors, suggesting that this suppression could reflect the existence of activated lymphocytes against donor antigens, and thus the rejection of a heart graft. The sensitivity of the ALSA test in these 47 heart graft recipients was 100%; however, the specificity was only 37.5%. It was also demonstrated that IL-2 N-mAb was indispensible, and the proper culture time courses and concentrations of stimulators were essential for the ALSA test. This preliminary study with 47 grafts revealed that the ALSA test was a promising noninvasive tool, which could be used in vitro to assist with the diagnosis of rejection post-heart transplantation.

  19. Ibrutinib interferes with the cell-mediated anti-tumor activities of therapeutic CD20 antibodies: implications for combination therapy

    OpenAIRE

    Roit, Fabio Da; Patrick J Engelberts; Taylor, Ronald P.; Breij, Esther C.W.; Gritti, Giuseppe; Rambaldi, Alessandro; Introna, Martino; Parren, Paul W H I; Beurskens, Frank J; Golay, Josée

    2015-01-01

    The novel Bruton tyrosine kinase inhibitor ibrutinib and phosphatidyl-4-5-biphosphate 3-kinase-δ inhibitor idelalisib are promising drugs for the treatment of chronic lymphocytic leukemia and B-cell non-Hodgkin lymphoma, either alone or in combination with anti-CD20 antibodies. We investigated the possible positive or negative impact of these drugs on all known mechanisms of action of both type I and type II anti-CD20 antibodies. Pretreatment with ibrutinib for 1 hour did not increase direct ...

  20. Antibodies to P-selectin glycoprotein ligand-1 block dendritic cell-mediated enterovirus 71 transmission and prevent virus-induced cells death.

    Science.gov (United States)

    Ren, Xiao-Xin; Li, Chuan; Xiong, Si-Dong; Huang, Zhong; Wang, Jian-Hua; Wang, Hai-Bo

    2015-01-01

    P-selectin glycoprotein ligand-1 (PSGL-1) has been proved to serve as the functional receptor for enterovirus 71 (EV71). We found the abundant expression of PSGL-1 on monocyte-derived dendritic cells (MDDCs). However, we have previously demonstrated that MDDCs did not support efficient replication of EV71. Dendritic cells (DCs) have been described to be subverted by various viruses including EV71 for viral dissemination, we thus explore the potential contribution of PSGL-1 on DC-mediated EV71 transmission. We found that the cell-surface-expressing PSGL-1 on MDDCs mediated EV71 binding, and intriguingly, these loaded-viruses on MDDCs could be transferred to encountered target cells; Prior-treatment with PSGL-1 antibodies or interference with PSGL-1 expression diminished MDDC-mediated EV71 transfer and rescued virus-induced cell death. Our data uncover a novel role of PSGL-1 in DC-mediated EV71 spread, and provide an insight into blocking primary EV71 infection.

  1. Serum major-histocompatibility-complex class Ⅰ-related chain A antibody detection for the evaluation of graft dysfunction in renal allograft recipients

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ming; LU Fu-ming; QU Lian-xi; HE Jun; YUAN Xiao-niao; GU Yong

    2011-01-01

    Background In addition to the well-known antibodies against human leukocyte antigens (HLA)-induced kidney-graft rejection, polymorphic major-histocompatibility-complex (MHC) class Ⅰ-related chain A (MICA) antigens can elicit antibodies and have been suggested to play a role in the antibody-mediated allograft rejection (AMR). We carded out a prospective study of MICA antibodies in post-renal transplant patients to determine the association between MICA antibodies, C4d staining, histological features, and graft outcome.Methods We tested 52 patients who had biopsy results due to graft dysfunction. The MICA antibodies in concurrent sera were determined by Luminex. All patients were followed up for one year after renal biopsy. The influence of antibody production on the function of graft was analyzed.Results Antibodies against MICA were positive in 15 out of the 52 patients (28.9%). The presence of MICA antibodies was associated with renal-allograft deterioration. During one-year follow-up, the estimated glomerular filtration rate (eGFR) decreased (24.0±3.4)% among recipients with anti-MICA antibodies. However, among recipients without anti-MICA antibodies, the eGFR has declined only (8.4+3.0)% (P=0.017). The association between C4d staining,histological features and MICA antibody production was found no significant difference.Conclusion Besides anti-HLA antibodies, the presence of post-transplant MICA antibody is associated with poor graft outcome and increases the risk of graft failure.

  2. Complement mediates human immunodeficiency virus type 1 infection of a human T cell line in a CD4- and antibody-independent fashion.

    Science.gov (United States)

    Boyer, V; Desgranges, C; Trabaud, M A; Fischer, E; Kazatchkine, M D

    1991-05-01

    Incubation of the human T cell lymphotropic virus (HTLV)-IIIB and HTLV-RF strains of human immunodeficiency virus type 1 (HIV-1) with normal seronegative human serum under conditions that allow complement activation resulted in enhancement of infection of the MT2 human T cell line cultured in the presence of low amounts of virus. Infection of MT2 cells was assessed by measuring reverse transcriptase activity in supernatants at day 9 of culture. Complement activation by viral suspensions occurred through the alternative pathway. Opsonization of HTLV-RF viral particles with complement was sufficient to allow a productive infection to occur in cells exposed to suboptimal amounts of virus. Infection of MT2 cells with suboptimal amounts of serum-opsonized HIV-1 was suppressed by blocking the C3dg receptor (CR2, CD21) on MT2 cells with monoclonal anti-CR2 antibody and rabbit F(ab')2 anti-mouse immunoglobulin antibodies. Blocking of the gp120-binding site on CD4 under similar experimental conditions had no inhibitory effect on infection of MT2 cells with opsonized virus. Opsonization of HIV-1 with seronegative serum also resulted in a CR2-mediated enhancement of the infection of normal peripheral blood mononuclear cells and T lymphocytes. These results indicate that complement in the absence of antibody may enhance infection of C3 receptor-bearing T cells with HIV-1, and that the interaction of opsonized virus with the CR2 receptor may result by itself in the infection of target T cells in a CD4- and antibody-independent fashion. PMID:1827139

  3. Variable Heat Rejection (VHR) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Develop advanced technologies to enable a variable heat rejection Thermal Control System (TCS) capable of operating through a wide range of thermal environments...

  4. Sustained Remission of Antineutrophil Cytoplasmic Antibody-Mediated Glomerulonephritis and Nephrotic Syndrome in Mixed Connective Tissue Disease

    OpenAIRE

    Konstantinov, Konstantin N.; Harris, Alexis A.; Barry, Marc; Murata, Glen H; Tzamaloukas, Antonios H.

    2013-01-01

    A woman diagnosed with mixed connective tissue disease (MCTD) developed an anti-myeloperoxidase (MPO) antineutrophil cytoplasmic antibody (ANCA) and nephrotic syndrome with normal serum creatinine. Percutaneous kidney biopsy showed pauci-immune glomerulonephritis with superimposed immune complex deposition. After treatment with cyclophophamide and prednisone, proteinuria decreased progressively to a level of 0.4 g/g creatinine, ANCA became undetectable, while serum creatinine remained normal ...

  5. Extension of the rejection sensitivity construct to the interpersonal functioning of gay men.

    Science.gov (United States)

    Pachankis, John E; Goldfried, Marvin R; Ramrattan, Melissa E

    2008-04-01

    On the basis of recent evidence suggesting that gay men are particularly likely to fear interpersonal rejection, the authors set out to extend the rejection sensitivity construct to the mental health concerns of gay men. After establishing a reliable and valid measure of the gay-related rejection sensitivity construct, the authors use this to test the mediating effect of internalized homophobia on the relationship between parental rejection of one's sexual orientation and sensitivity to future gay-related rejection. The present data support this mediational model and also establish rejection sensitivity's unique contribution to unassertive interpersonal behavior in the context of internalized homophobia and parental rejection. The authors conclude that gay-related rejection sensitivity is a useful construct for clinicians working with gay men given the impact that past gay-related rejection can have on their gay clients' present cognitive-affective-behavioral functioning. The authors discuss the possibility of revising rejection-prone schemas in clinical work with gay men. Future research is necessary to further examine the internal processing and interpersonal functioning of gay men by using existing constructs (or modifications of them) that are likely to be particularly relevant to the unique concerns of this population. PMID:18377126

  6. Donor-specific antibodies accelerate arteriosclerosis after kidney transplantation.

    Science.gov (United States)

    Hill, Gary S; Nochy, Dominique; Bruneval, Patrick; Duong van Huyen, J P; Glotz, Denis; Suberbielle, Caroline; Zuber, Julien; Anglicheau, Dany; Empana, Jean-Philippe; Legendre, Christophe; Loupy, Alexandre

    2011-05-01

    In biopsies of renal allografts, arteriosclerosis is often more severe than expected based on the age of the donor, even without a history of rejection vasculitis. To determine whether preformed donor-specific antibodies (DSAs) may contribute to the severity of arteriosclerosis, we examined protocol biopsies from patients with (n=40) or without (n=59) DSA after excluding those with any evidence of vasculitis. Among DSA-positive patients, arteriosclerosis significantly progressed between month 3 and month 12 after transplant (mean Banff cv score 0.65 ± 0.11 to 1.12 ± 0.10, P=0.014); in contrast, among DSA-negative patients, we did not detect a statistically significant progression during the same timeframe (mean Banff cv score 0.65 ± 0.11 to 0.81 ± 0.10, P=not significant). Available biopsies at later time points supported a rate of progression of arteriosclerosis in DSA-negative patients that was approximately one third that in DSA-positive patients. Accelerated arteriosclerosis was significantly associated with peritubular capillary leukocytic infiltration, glomerulitis, subclinical antibody-mediated rejection, and interstitial inflammation. In conclusion, these data support the hypothesis that donor-specific antibodies dramatically accelerate post-transplant progression of arteriosclerosis.

  7. Antibody-dependent cellular cytotoxicity and skin disease

    Energy Technology Data Exchange (ETDEWEB)

    Norris, D.A.; Lee, L.A.

    1985-07-01

    Antibody dependent cellular cytotoxicity (ADCC) is a recently described mechanism of immunologic lysis in which cellular targets sensitized by specific antibodies are efficiently and selectively lysed by Fc receptor (FcR) bearing nonspecific effectors. Immunoglobulins of various classes (IgG, IgM, IgA, IgE) and various cellular effectors (large granular lymphocytes, monocyte/macrophages, T lymphocytes, neutrophils, and eosinophils) can induce ADCC in vitro, and the importance of ADCC in vivo is being tested experimentally in resistance to viral, bacterial, and parasitic infection, in tumor surveillance, in allograft rejection, and in inflammatory diseases. There is much indirect evidence that ADCC may be the mechanism of damage of different cellular targets in skin diseases, but the best direct evidence concerns immunologic keratinocyte damage, especially in cutaneous lupus erythematosus (LE). The authors have shown that keratinocytes of several species are highly susceptible to lymphocyte and monocyte-mediated ADCC, but not to neutrophil or eosinophil ADCC in vitro using two different cytotoxicity assays. In contrast, complement was a relatively ineffective mediator of lysis of metabolically intact keratinocyte targets. Patients with certain cutaneous lupus syndromes have serum antibodies capable of inducing monocyte and lymphocyte ADCC of targets coated with extractable nuclear antigens. The authors have shown that these antigens apparently move to the cell membrane of keratinocytes in vitro following ultraviolet irradiation. In an animal model, they have shown that antibodies to SSA/Ro bind to human keratinocytes in vivo, especially after ultraviolet irradiation.

  8. Characterization of the mechanism of protection mediated by CS-D7, a monoclonal antibody to Staphylococcus aureus iron regulated surface determinant B (IsdB

    Directory of Open Access Journals (Sweden)

    Gregory ePancari

    2012-03-01

    Full Text Available We previously reported the development of a human monoclonal antibody (CS-D7, IgG1 with specificity and affinity for the iron regulated surface determinant B (IsdB of Staphylococcus aureus. CS-D7 mediates opsonophagocytic killing in vitro and protection in a murine sepsis model. In light of recent data indicating that IsdB specific T cells (CD4+, Th17, not Ab, mediate protection after vaccination with IsdB, it is important to investigate the mechanism of protection mediated by CS-D7. The mAb was examined to determine if it blocked heme binding to IsdB in vitro. The mAb was not found to have heme blocking activity, nor did it prevent bacterial growth under in vivo conditions, in an implanted growth chamber. To assess the role of the mAb Fc a point mutation was introduced at aa 297 (CS-D7●N297A. This point mutation removes Fc effector functions. In vitro analysis of the mutein confirmed that it lacked measurable binding to FcγR, and that it did not fix complement. The mutein had dramatically reduced in vitro opsonic OP activity compared to CS-D7. Nonetheless, the mutein conferred protection equivalent to the wild type mAb in the murine sepsis model. Both wild type and mutein mAbs were efficacious in FcγR deletion mice (including both FcγRII-/- mice and FcγRIII-/- mice, indicating that these receptors were not essential for mAb mediated protection in vivo. Protection mediated by CS-D7 was lost in Balb/c mice depleted of C3 with cobra venom factor (CFV, was lost in mice depleted of superoxide dismutase (SOD in P47phox deletion mice, and was absent in SCID mice. Enhanced clearance of S. aureus in the liver of CS-D7 treated mice and enhanced production of INF-γ, but not of IL17, may play a role in the mechanism of protection mediated by the mAb. CS-D7 apparently mediates survival in challenged mice through a mechanism involving complement, phagocytes, and lymphocytes, but which does not depend on interaction with FcγR, or on blocking heme

  9. Transplant rejection in terrestrial molluscs

    Directory of Open Access Journals (Sweden)

    E Furuta

    2011-01-01

    Full Text Available To know whether or not molluscs are capable of recognizing tissue allo-antigens, dorsal skin-allografts were exchanged between adult terrestrial slug, Incilaria fruhstorferi. We succeeded for the first time in orthotopic transplantation of allografts and observed chronic rejection of allografts. Cellular changes in the rejection process continued over for 40 days. Two functional types of “effector” cells were recognized at the rejection site, but they were observed to be macrophages possessing perforin granules and phagocytosing damaged cells of the allograft. Three days after transplantation, the perforin-positive cells were recognized only in the recipient tissue surrounding the allograft. Five days after transplantation, these cells started to appear in the graft, while they disappeared from the host tissue. However, TUNEL-positive cells (apoptotic cells were not observed throughout the graft-rejection process. Electron microscopic examination of the graft tissue revealed autophagic degeneration of epithelial cells, mucous cells, pigment cells, fibroblasts, and muscle cells. These observations suggest that the slugs have the capability to recognize differences in cell-surface molecules between the allogeneic and recipient tissue, and that an allograft is chronically rejected due to a type of immunocyte (macrophage that can induce perforin-dependent cell death

  10. Delayed hyperacute rejection in a patient who developed clostridium difficile infection after ABO-incompatible kidney transplantation

    Directory of Open Access Journals (Sweden)

    Gerald S Lipshutz

    2010-11-01

    the surface of bacterial cell wall occurring before the firm establishment of accommodation can trigger the onset of acute antibody-mediated rejection. We herein report a case of delayed hyperacute rejection in an A1 to O, ABO incompatible transplant recipient following an episode of Clostridium difficile infection.Keywords: ABO incompatible transplantation, delayed hyperacute rejection, kidney transplantation, Clostridium difficile infection

  11. Anti-HMGCR antibodies as a biomarker for immune-mediated necrotizing myopathies: A history of statins and experience from a large international multi-center study.

    Science.gov (United States)

    Musset, Lucile; Allenbach, Yves; Benveniste, Olivier; Boyer, Olivier; Bossuyt, Xavier; Bentow, Chelsea; Phillips, Joe; Mammen, Andrew; Van Damme, Philip; Westhovens, René; Ghirardello, Anna; Doria, Andrea; Choi, May Y; Fritzler, Marvin J; Schmeling, Heinrike; Muro, Yoshinao; García-De La Torre, Ignacio; Ortiz-Villalvazo, Miguel A; Bizzaro, Nicola; Infantino, Maria; Imbastaro, Tiziana; Peng, Qinglin; Wang, Guochun; Vencovský, Jiří; Klein, Martin; Krystufkova, Olga; Franceschini, Franco; Fredi, Micaela; Hue, Sophie; Belmondo, Thibaut; Danko, Katalin; Mahler, Michael

    2016-10-01

    In an effort to find naturally occurring substances that reduce cholesterol by inhibiting 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR), statins were first discovered by Endo in 1972. With the widespread prescription and use of statins to decrease morbidity from myocardial infarction and stroke, it was noted that approximately 5% of all statin users experienced muscle pain and weakness during treatment. In a smaller proportion of patients, the myopathy progressed to severe morbidity marked by proximal weakness and severe muscle wasting. Remarkably, Mammen and colleagues were the first to discover that the molecular target of statins, 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR), is an autoantibody target in patients that develop an immune-mediated necrotizing myopathy (IMNM). These observations have been confirmed in a number of studies but, until today, a multi-center, international study of IMNM, related idiopathic inflammatory myopathies (IIM), other auto-inflammatory conditions and controls has not been published. Accordingly, an international, multi-center study investigated the utility of anti-HMGCR antibodies in the diagnosis of statin-associated IMNM in comparison to different forms of IIM and controls. This study included samples from patients with different forms of IIM (n=1250) and patients with other diseases (n=656) that were collected from twelve sites and tested for anti-HMGCR antibodies by ELISA. This study confirmed that anti-HMGCR autoantibodies, when found in conjunction with statin use, characterize a subset of IIM who are older and have necrosis on muscle biopsy. Taken together, the data to date indicates that testing for anti-HMGCR antibodies is important in the differential diagnosis of IIM and might be considered for future classification criteria.

  12. VEGFR2 targeted antibody fused with MICA stimulates NKG2D mediated immunosurveillance and exhibits potent anti-tumor activity against breast cancer.

    Science.gov (United States)

    Xie, Wei; Liu, Fang; Wang, Youfu; Ren, Xueyan; Wang, Tong; Chen, Zhiguo; Tang, Mingying; Sun, Fumou; Li, Zhaoting; Wang, Min; Zhang, Juan

    2016-03-29

    Binding of MHC class I-related chain molecules A and B (MICA/B) to the natural killer (NK) cell receptor NK group 2, member D (NKG2D) is thought critical for activating NK-mediated immunosurveillance. Angiogenesis is important for tumor growth and interfering with angiogenesis using the fully human IgG1 anti-VEGFR2 (vascular endothelial growth factor receptor 2) antibody (mAb04) can be effective in treating malignancy. In an effort to make mAb04 more effective we have generated a novel antibody fusion protein (mAb04-MICA) consisting of mAb04 and MICA. We found that mAb04-MICA maintained the anti-angiogenic and antineoplastic activities of mAb04, and also enhanced immunosurveillance activated by the NKG2D pathway. Moreover, in human breast tumor-bearing nude mice, mAb04-MICA demonstrated superior anti-tumor efficacy compared to combination therapy of mAb04 + Docetaxel or Avastin + Docetaxel, highlighting the immunostimulatory effect of MICA. In conclusion, mAb04-MICA provided new inspiration for anti-tumor treatment and had prospects for clinical application.

  13. Antibody-mediated targeting of the urokinase-type plasminogen activator proteolytic function neutralizes fibrinolysis in vivo

    DEFF Research Database (Denmark)

    Lund, Ida K; Jögi, Annika; Rønø, Birgitte;

    2008-01-01

    was directed against the first of these reactions. We additionally provide evidence that mU1, but not mU3, successfully targets uPA-dependent processes in vivo. Hence, systemic administration of mU1 (i) rescued mice treated with a uPA-activable anthrax protoxin and (ii) impaired uPA-mediated hepatic...

  14. Antibodies mediate formation of neutrophil extracellular traps in the middle ear and facilitate secondary pneumococcal otitis media.

    Science.gov (United States)

    Short, Kirsty R; von Köckritz-Blickwede, Maren; Langereis, Jeroen D; Chew, Keng Yih; Job, Emma R; Armitage, Charles W; Hatcher, Brandon; Fujihashi, Kohtaro; Reading, Patrick C; Hermans, Peter W; Wijburg, Odilia L; Diavatopoulos, Dimitri A

    2014-01-01

    Otitis media (OM) (a middle ear infection) is a common childhood illness that can leave some children with permanent hearing loss. OM can arise following infection with a variety of different pathogens, including a coinfection with influenza A virus (IAV) and Streptococcus pneumoniae (the pneumococcus). We and others have demonstrated that coinfection with IAV facilitates the replication of pneumococci in the middle ear. Specifically, we used a mouse model of OM to show that IAV facilitates the outgrowth of S. pneumoniae in the middle ear by inducing middle ear inflammation. Here, we seek to understand how the host inflammatory response facilitates bacterial outgrowth in the middle ear. Using B cell-deficient infant mice, we show that antibodies play a crucial role in facilitating pneumococcal replication. We subsequently show that this is due to antibody-dependent neutrophil extracellular trap (NET) formation in the middle ear, which, instead of clearing the infection, allows the bacteria to replicate. We further demonstrate the importance of these NETs as a potential therapeutic target through the transtympanic administration of a DNase, which effectively reduces the bacterial load in the middle ear. Taken together, these data provide novel insight into how pneumococci are able to replicate in the middle ear cavity and induce disease.

  15. Rapid alternative to the clonogenic assay for measuring antibody and complement-mediated killing of tumor cells

    International Nuclear Information System (INIS)

    A study of the methods used to quantitate killing of tumor cells by antibody and complement has highlighted a number of problems. Using leukemia as a model, the authors have found that the release of 51Cr from labeled tumor cells treated with antibody and complement can be an equivocal measure of cell viability. Combined with its restricted sensitivity (less than a 2 log range of cell killing) this makes this widely used assay of questionable value for detecting small numbers of viable cells, or for identifying subpopulations of complement-resistant cells. As an alternative a [125I]iododeoxyuridine uptake assay has been developed, that combines the simplicity and rapidity of the 51Cr release technique with the sensitivity of a clonogenic assay. This method eliminates the problem of spontaneous isotope release, inherent in prelabeling assays, and variability from experiment to experiment can be avoided by including a viable cell standard curve within each assay. The sensitivity of the 125IUdR uptake method, which can be completed within a day, is similar to that of a 10 day methylcellulose cloning assay and was capable of detecting the presence of a minor subpopulation of complement-resistant tumor cells

  16. Anti-HMGB1 Neutralizing Antibody Ameliorates Neutrophilic Airway Inflammation by Suppressing Dendritic Cell-Mediated Th17 Polarization

    Directory of Open Access Journals (Sweden)

    Fang Zhang

    2014-01-01

    Full Text Available We demonstrate that high mobility group box 1 protein (HMGB1 directs Th17 skewing by regulating dendritic cell (DC function. First, our in vitro studies reveal that recombinant HMGB1 (rHMGB1 activates myeloid DCs to produce IL-23 in vitro, and rHMGB1-activated DCs prime naïve lymphocytes to produce the Th17 cytokine IL-17A. Second, we demonstrate that anti-HMGB1 neutralizing antibody attenuates HMGB1 expression, neutrophilic inflammation, airway hyperresponsiveness, and Th17-related cytokine secretion in vivo by using a murine model of neutrophilic asthma induced by ovalbumin (OVA plus lipopolysaccharide (LPS. Furthermore, anti-HMGB1 neutralizing antibody decreases the number of Th17 cells in lung cells and suppresses the production of IL-23 by lung CD11C+ APCs. Finally, we show that intranasal adoptive transfer of rHMGB1-activated DCs was sufficient to restore lung neutrophilic inflammation and the Th17 response in a DC-driven model of asthma, whereas the transfer of rHMGB1 plus anti-HMGB1-treated mDCs significantly reduced these inflammation phenotypes. These data suggest, for the first time, that HMGB1 drives the DC-polarized Th17-type response in allergic lung inflammation and that blocking HMGB1 may benefit the attenuation of neutrophilic airway inflammation in asthma.

  17. Interaction of human IgG chimeric antibodies with the human FcRI and FcRII receptors: requirements for antibody-mediated host cell-target cell interaction.

    Science.gov (United States)

    Walker, M R; Woof, J M; Brüggemann, M; Jefferis, R; Burton, D R

    1989-04-01

    Chimeric monoclonal antibodies (McAb), specific for the hapten 5-iodo-4-hydroxy-3-nitrophenacetyl (NIP), expressing human IgG1, IgG2, IgG3 and IgG4 subclass constant domains, have been examined for their ability to interact with the human FcRII receptor. Human red blood cells (RBC) sensitized by each of these McAbs have been assayed for their ability to form rosettes with the human histiocytic lymphoma U937 cell line, human B cell line Daudi and erythroblastoid K562 cell line. IgG1 and IgG3 sensitized RBC formed significant rosettes with the FcR- and FcRII+ Daudi and K562 cell lines, the percentage of cells forming rosettes being directly proportional to the degree of sensitization of the RBC. Bromelin treating Daudi cells did not alter this pattern of reactivity, whereas bromelin treated FcRI+ and FcRII+ U937 cells formed significant resettes with IgG1, IgG3 and IgG4 sensitized RBC, demonstrating a difference in the IgG subclass specificity between human FcRI and FcRII. Murine IgG2b anti-NIP sensitized RBC did not form rosettes with any cell line tested; however, RBC sensitized by some members of a panel of murine IgG1 McAb, specific for the glycophorin A molecule, were able to form rosettes with Daudi, U937 and K562 cells. This interaction was enhanced by bromelin treating the Daudi or U937 cells and can be correlated to the disposition of the epitopes recognized, relative to the target cell membrane, those McAbs recognizing epitopes furthest from the RBC surface being most effective in interacting with FcRII. The data are interpreted in terms of a simple model for antibody-mediated cell--cell interaction. PMID:2716734

  18. Antibody-mediated enhancement of human immunodeficiency virus type 1 infectivity is determined by the structure of gp120 and depends on modulation of the gp120-CCR5 interaction

    NARCIS (Netherlands)

    C. Guillon (Christophe); M. Schutten (Martin); P.H.M. Boers (Patrick); R.A. Gruters (Rob); A.D.M.E. Osterhaus (Ab)

    2002-01-01

    textabstractIn this study, we characterized the viral determinants of coreceptor usage in relation to susceptibility to antibody-mediated neutralization or enhancement of infectivity by using chimeras of three highly related human immunodeficiency virus type 1 (HIV-1) isolates of different phenotype

  19. Thyroid Antibodies

    Science.gov (United States)

    ... be limited. Home Visit Global Sites Search Help? Thyroid Antibodies Share this page: Was this page helpful? Also known as: Thyroid Autoantibodies; Antithyroid Antibodies; Antimicrosomal Antibody; Thyroid Microsomal Antibody; ...

  20. Prostanoids modulate inflammation and alloimmune responses during graft rejection

    Directory of Open Access Journals (Sweden)

    P.N. Rocha

    2005-12-01

    Full Text Available Acute rejection of a transplanted organ is characterized by intense inflammation within the graft. Yet, for many years transplant researchers have overlooked the role of classic mediators of inflammation such as prostaglandins and thromboxane (prostanoids in alloimmune responses. It has been demonstrated that local production of prostanoids within the allograft is increased during an episode of acute rejection and that these molecules are able to interfere with graft function by modulating vascular tone, capillary permeability, and platelet aggregation. Experimental data also suggest that prostanoids may participate in alloimmune responses by directly modulating T lymphocyte and antigen-presenting cell function. In the present paper, we provide a brief overview of the alloimmune response, of prostanoid biology, and discuss the available evidence for the role of prostaglandin E2 and thromboxane A2 in graft rejection.

  1. Successful therapy with rituximab of refractory acute humoral renal transplant rejection: a case report.

    Science.gov (United States)

    Celik, A; Saglam, F; Cavdar, C; Sifil, A; Atila, K; Sarioglu, S; Bora, S; Gulay, H; Camsari, T

    2008-01-01

    Acute humoral rejection (AHR) is generally less responsive to conventional anti-rejection treatment with consequent allograft losses. Therapeutic options include antilymphocyte antibody (ATG), intravenous immunglobulin (IVIG), plasmapheresis, or immunoadsorption with protein A together with intensification of immunsuppression with a tacrolimus/mycophenolate mofetil combination. This report describes a transplant recipient who responded to rituximab therapy as treatment for steroid-, ATG-, IVIG-, and plasmapheresis-resistant AHR. PMID:18261611

  2. The push of social pain: Does rejection's sting motivate subsequent social reconnection?

    Science.gov (United States)

    Chester, David S; DeWall, C Nathan; Pond, Richard S

    2016-06-01

    Physical pain motivates the healing of somatic injuries, yet it remains unknown whether social pain serves a similarly reparative function toward social injuries. Given the substantial overlap between physical and social pain, we predicted that social pain would mediate the effect of rejection on greater motivation for social reconnection and affiliative behavior toward rejecters. In Study 1, the effect of rejection on an increased need to belong was mediated by reports of more intense social pain. In Study 2, three neural signatures of social pain (i.e., activity in the dorsal anterior cingulate cortex, left and right anterior insula during social rejection), each predicted greater behavioral proximity to rejecters. Our findings reify the overlap between social and physical pain. Furthermore, these results are some of the first to demonstrate the reparative nature of social pain and lend insight into how this process may be harnessed to promote postrejection reconnection. PMID:26912270

  3. Antibody-mediated targeting of iron oxide nanoparticles to the folate receptor alpha increases tumor cell association in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    Ndong C

    2015-04-01

    Full Text Available Christian Ndong,1 Seiko Toraya-Brown,2 Katsiaryna Kekalo,1 Ian Baker,1 Tillman U Gerngross,1,3,4 Steven N Fiering,2,5,6 Karl E Griswold1,3,6 1Thayer School of Engineering, Dartmouth, Hanover, NH, USA; 2Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA; 3Department of Biological Sciences, Dartmouth, Hanover, NH, USA; 4Department of Chemistry, Dartmouth, Hanover, NH, USA; 5Department of Genetics, Geisel School of Medicine at Dartmouth, Hanover, NH, USA; 6Norris Cotton Cancer Center, Lebanon, NH, USA Abstract: Active molecular targeting has become an important aspect of nanoparticle development for oncology indications. Here, we describe molecular targeting of iron oxide nanoparticles (IONPs to the folate receptor alpha (FOLRα using an engineered antibody fragment (Ffab. Compared to control nanoparticles targeting the non-relevant botulinum toxin, the Ffab-IONP constructs selectively accumulated on FOLRα-overexpressing cancer cells in vitro, where they exhibited the capacity to internalize into intracellular vesicles. Similarly, Ffab-IONPs homed to FOLRα-positive tumors upon intraperitoneal administration in an orthotopic murine xenograft model of ovarian cancer, whereas negative control particles showed no detectable tumor accumulation. Interestingly, Ffab-IONPs built with custom 120 nm nanoparticles exhibited lower in vitro targeting efficiency when compared to those built with commercially sourced 180 nm nanoparticles. In vivo, however, the two Ffab-IONP platforms achieved equivalent tumor homing, although the smaller 120 nm IONPs were more prone to liver sequestration. Overall, the results show that Ffab-mediated targeting of IONPs yields specific, high-level accumulation within cancer cells, and this fact suggests that Ffab-IONPs could have future utility in ovarian cancer diagnostics and therapy. Keywords: nanoparticle targeting, antibody fragment, biodistribution, ovarian cancer

  4. Antibody-Mediated Targeting of siRNA Via the Human Insulin Receptor Using Avidin-Biotin Technology

    Science.gov (United States)

    Xia, Chun-Fang; Boado, Ruben J.; Pardridge, William M.

    2013-01-01

    Delivery of short interfering RNA (siRNA) to cells in culture, and in vivo, is possible with combined use of a receptor-specific monoclonal antibody (MAb) and avidin-biotin technology. In the present studies, the luciferase gene is transiently expressed in human 293 epithelial cells. The siRNA delivery system is comprised of the siRNA, mono-biotinylated on the 3′-terminus of the sense strand, and a conjugate of streptavidin (SA) and a MAb to the human insulin receptor (HIR). Exposure of cells to 3′-biotinyl-siRNA bound to the HIRMAb/SA conjugate, but not to unconjugated SA, avidin, or the HIRMAb, causes a >90% reduction in luciferase gene expression. The receptor-targeted siRNA effect is maximal at 48 hours after delivery of the siRNA to the cells, and the effect is lost by 7 days after a single application of the targeted siRNA in culture. The KI of the receptor-targeted siRNA inhibition of gene expresssion is 30.5 ± 11.7 nM, and significant inhibition is observed with siRNA concentrations as low as 3 nM. In conclusion, the combination of a receptor-specific targeting ligand, such as the HIRMAb, and avidin-biotin technology, allows for high affinity capture of the mono-biotinylated siRNA by the targeting MAb. The siRNA is effectively delivered to the cytosol of cells and knockdown of gene expression with the HIRMAb/SA delivery system is comparable to RNA interference effects obtained with cationic polyplexes. Whereas the use of cationic polyplexes in vivo is problematic, the bond between the targeting MAb and the siRNA is stable with avidin-biotin technology, and RNAi effects at distant sites such as brain are observed in vivo following an intravenous administration of the targeted siRNA. PMID:19093871

  5. Antibody-Mediated Inhibition of the FGFR1c Isoform Induces a Catabolic Lean State in Siberian Hamsters.

    Science.gov (United States)

    Samms, Ricardo J; Lewis, Jo E; Lory, Alex; Fowler, Maxine J; Cooper, Scott; Warner, Amy; Emmerson, Paul; Adams, Andrew C; Luckett, Jeni C; Perkins, Alan C; Wilson, Dana; Barrett, Perry; Tsintzas, Kostas; Ebling, Francis J P

    2015-11-16

    Hypothalamic tanycytes are considered to function as sensors of peripheral metabolism. To facilitate this role, they express a wide range of receptors, including fibroblast growth factor receptor 1 (FGFR1). Using a monoclonal antibody (IMC-H7) that selectively antagonizes the FGFR1c isoform, we investigated possible actions of FGFR1c in a natural animal model of adiposity, the Siberian hamster. Infusion of IMC-H7 into the third ventricle suppressed appetite and increased energy expenditure. Likewise, peripheral treatment with IMC-H7 decreased appetite and body weight and increased energy expenditure and fat oxidation. A greater reduction in body weight and caloric intake was observed in response to IMC-H7 during the long-day fat state as compared to the short-day lean state. This enhanced response to IMC-H7 was also observed in calorically restricted hamsters maintained in long days, suggesting that it is the central photoperiodic state rather than the peripheral adiposity that determines the response to FGFR1c antagonism. Hypothalamic thyroid hormone availability is controlled by deiodinase enzymes (DIO2 and DIO3) expressed in tanycytes and is the key regulator of seasonal cycles of energy balance. Therefore, we determined the effect of IMC-H7 on hypothalamic expression of these deiodinase enzymes. The reductions in food intake and body weight were always associated with decreased expression of DIO2 in the hypothalamic ependymal cell layer containing tanycytes. These data provide further support for the notion the tanycytes are an important component of the mechanism by which the hypothalamus integrates central and peripheral signals to regulate energy intake and expenditure.

  6. A Longitudinal Study of Rejecting and Autonomy-Restrictive Parenting, Rejection Sensitivity, and Socioemotional Symptoms in Early Adolescents.

    Science.gov (United States)

    Rowe, Susan L; Gembeck, Melanie J Zimmer; Rudolph, Julia; Nesdale, Drew

    2015-08-01

    Rejection sensitivity (RS) has been defined as the tendency to readily perceive and overreact to interpersonal rejection. The primary aim of this study was to test key propositions of RS theory, namely that rejecting experiences in relationships with parents are antecedents of early adolescents' future RS and symptomatology. We also expanded this to consider autonomy-restrictive parenting, given the importance of autonomy in early adolescence. Participants were 601 early adolescents (age 9 to 13 years old, 51% boys) from three schools in Australia. Students completed questionnaires at school about parent and peer relationships, RS, loneliness, social anxiety, and depression at two times with a 14-month lag between assessments. Parents also reported on adolescents' difficulties at Time 1 (T1). It was anticipated that more experience of parental rejection, coercion, and psychological control would be associated with adolescents' escalating RS and symptoms over time, even after accounting for peer victimisation, and that RS would mediate associations between parenting and symptoms. Structural equation modelling supported these hypotheses. Parent coercion was associated with adolescents' increasing symptoms of social anxiety and RS over time, and parent psychological control was associated with increasing depressive symptoms over time. Indirect effects via RS were also found, with parent rejection and psychological control linked to higher T1 RS, which was then associated with increasing loneliness and RS. Lastly, in a separate model, peer victimisation and RS, but not parenting practices, were positively associated with concurrent parent reports of adolescents' difficulties.

  7. Mediation as Signal

    NARCIS (Netherlands)

    Holler, M.J.; Lindner, I.

    2004-01-01

    This paper analyzes mediation as a signal. Starting from a stylized case, a game theoretical model of one-sided incomplete information, taken from Cho and Kreps (1987), is applied to discuss strategic effects of mediation. It turns out that to reject mediation can be interpreted as a ”negative signa

  8. The role of spleen in rejection of concordant liver xenograft%异种肝移植免疫排斥反应中脾脏的作用

    Institute of Scientific and Technical Information of China (English)

    谈景旺; 姚和祥; 杨甲梅; 钱光相; 吴梦超

    2000-01-01

    Objectives To study the role of spleen in liver xenogenic rejection of Hamster-to-Rat.Methods The in situ liver transplantation model of hamster-to-rat was developed by using three-cuff technique to observe the pathological change of graft and spleen in xenogenic rejection.The production of antibody of rat and the expression of PCNA in spleen were detected by using immunohistochemistry.In addition.the effects of several immunosuppression measures on the survival time and rejection after transplantation were observed.Results In xenogenic rejection,the spleen prolifcrated rapidly,its marginal gone obviously thickened and the titer of antibody in serum was increased rapidly.The grafts were injured.The cyclophosphoramide can selectively inhibit the proliferation of marginal zone of the spleen and reduce greatly the titer of antibody in serum.Cyclosporine A plus splenectomy can suppress the xenogenic rejection and prolong the recipient's survival time(P<0.01),but the time of splenectomy was delayed 3 days,the rejection cann't be suppressed,and the recipient's survival time cann't be prolonged markedly(P>0.05).Conclusions In concordant liver xenograft.the antibody mediating humoral immunity come mainly from the marginal zone of spleen.The lymnphocytes mediating cdluiar immunity from the spleen located at the area of immunine rejection at third pcxstoperative day.%目的 探讨脾脏在仓鼠到大鼠异种肝移植中的体液免疫、细胞免疫作用.方法 三袖套法建立仓鼠到大鼠原位肝移植模型,观察移植术后肝脏和脾脏的病理变化;采用补体介导的细胞毒实验检测异种肝移植术后血浆中抗仓鼠抗体滴度的变化;运用免疫组织化学的方法检测脾脏中大鼠抗体的产生、脾脏增殖细胞核抗原(PCNA)的表达;并观察环孢素A、环磷酰胺、切脾对移植术后生存时间及免疫排斥反应的影响.结果 异种肝移植术后免疫排斥反应发生时,脾脏急剧增大,边缘区明显

  9. The herpes virus Fc receptor gE-gI mediates antibody bipolar bridging to clear viral antigens from the cell surface.

    Directory of Open Access Journals (Sweden)

    Blaise Ndjamen

    2014-03-01

    Full Text Available The Herpes Simplex Virus 1 (HSV-1 glycoprotein gE-gI is a transmembrane Fc receptor found on the surface of infected cells and virions that binds human immunoglobulin G (hIgG. gE-gI can also participate in antibody bipolar bridging (ABB, a process by which the antigen-binding fragments (Fabs of the IgG bind a viral antigen while the Fc binds to gE-gI. IgG Fc binds gE-gI at basic, but not acidic, pH, suggesting that IgG bound at extracellular pH by cell surface gE-gI would dissociate and be degraded in acidic endosomes/lysosomes if endocytosed. The fate of viral antigens associated with gE-gI-bound IgG had been unknown: they could remain at the cell surface or be endocytosed with IgG. Here, we developed an in vitro model system for ABB and investigated the trafficking of ABB complexes using 4-D confocal fluorescence imaging of ABB complexes with transferrin or epidermal growth factor, well-characterized intracellular trafficking markers. Our data showed that cells expressing gE-gI and the viral antigen HSV-1 gD endocytosed anti-gD IgG and gD in a gE-gI-dependent process, resulting in lysosomal localization. These results suggest that gE-gI can mediate clearance of infected cell surfaces of anti-viral host IgG and viral antigens to evade IgG-mediated responses, representing a general mechanism for viral Fc receptors in immune evasion and viral pathogenesis.

  10. Antibody induced CD4 down-modulation of T cells is site-specifically mediated by CD64(+) cells.

    Science.gov (United States)

    Vogel, Stephanie; Grabski, Elena; Buschjäger, Daniela; Klawonn, Frank; Döring, Marius; Wang, Junxi; Fletcher, Erika; Bechmann, Ingo; Witte, Torsten; Durisin, Martin; Schraven, Burkhart; Mangsbo, Sara M; Schönfeld, Kurt; Czeloth, Niklas; Kalinke, Ulrich

    2015-12-16

    Treatment of PBMC with the CD4-specific mAb BT-061 induces CD4 down-modulation of T cells. Here we report that addition of BT-061 to purified T cells did not confer this effect, whereas incubation of T cells in BT-061 coated wells restored CD4 down-modulation. These results implied that Fcγ receptor mediated cell-cell interactions played a role. In consistence with this hypothesis PBMC depleted of CD64(+) monocytes did not confer CD4 down-modulation of BT-061 decorated T cells. Strikingly, CD4 down-modulation was observed in BT-061 treated synovial fluid punctuated from patients' inflamed joints that comprised enhanced numbers of CD64(+) cells. In contrast, in a circulating whole blood system injection of BT-061 did not induce CD4 down-modulation, due to CD64 saturation by serum IgG. Similarly, tonsil derived mononuclear cells devoid of CD64(+) cells did not show CD4 down-modulation, whereas addition of blood derived monocytes restored the effect. Thus, the interaction of BT-061 decorated T cells with CD64(+) cells is needed for CD4 down-modulation, implying that in patients BT-061 would primarily induce CD4 down-modulation at inflammatory sites. These results highlight the need not only to examine the interaction of a given mAb with single FcγR, but also the immunological environment that is appropriate to support such interactions.

  11. Peer Group Rejection and Children's Outgroup Prejudice

    Science.gov (United States)

    Nesdale, Drew; Durkin, Kevin; Maass, Anne; Kiesner, Jeff; Griffiths, Judith; Daly, Josh; McKenzie, David

    2010-01-01

    Two simulation studies examined the effect of peer group rejection on 7 and 9 year old children's outgroup prejudice. In Study 1, children (n = 88) pretended that they were accepted or rejected by their assigned group, prior to competing with a lower status outgroup. Results indicated that rejected versus accepted children showed increased…

  12. 7 CFR 58.136 - Rejected milk.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Rejected milk. 58.136 Section 58.136 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Milk § 58.136 Rejected milk. A plant shall reject specific milk from a producer if the milk fails...

  13. Antibodies and IL-3 support helminth-induced basophil expansion.

    Science.gov (United States)

    Herbst, Tina; Esser, Julia; Prati, Moira; Kulagin, Manuel; Stettler, Rebecca; Zaiss, Mario M; Hewitson, James P; Merky, Patrick; Verbeek, Joseph S; Bourquin, Carole; Camberis, Mali; Prout, Melanie; Maizels, Rick M; Le Gros, Graham; Harris, Nicola L

    2012-09-11

    Basophils are powerful mediators of Th2 immunity and are present in increased numbers during allergic inflammation and helminth infection. Despite their ability to potentiate Th2 immunity the mechanisms regulating basophil development remain largely unknown. We have found a unique role for isotype-switched antibodies in promoting helminth-induced basophil production following infection of mice with Heligmosomoides polygyrus bakeri or Nippostrongylus brasiliensis. H. polygyrus bakeri-induced basophil expansion was found to occur within the bone marrow, and to a lesser extent the spleen, and was IL-3 dependent. IL-3 was largely produced by CD4(+)CD49b(+)NK1.1(-) effector T cells at these sites, and required the IL-4Rα chain. However, antibody-deficient mice exhibited defective basophil mobilization despite intact T-cell IL-3 production, and supplementation of mice with immune serum could promote basophilia independently of required IL-4Rα signaling. Helminth-induced eosinophilia was not affected by the deficiency in isotype-switched antibodies, suggesting a direct effect on basophils rather than through priming of Th2 responses. Although normal type 2 immunity occurred in the basopenic mice following primary infection with H. polygyrus bakeri, parasite rejection following challenge infection was impaired. These data reveal a role for isotype-switched antibodies in promoting basophil expansion and effector function following helminth infection. PMID:22930820

  14. Neuropeptide-mediated regulation of hapten-specific IgE responses in mice. II. Mechanisms of substance P-mediated isotype-specific suppression of BPO-specific IgE antibody-forming cell responses induced in vitro.

    Science.gov (United States)

    Carucci, J A; Herrick, C A; Durkin, H G

    1994-01-01

    Previous studies in our laboratory have shown that substance P (SP), injected into benzylpenicilloyl-keyhole limpet hemocyanin (BPO-KLH) sensitized mice at the peak of the benzylpenicilloyl (BPO)-specific IgE response, suppressed these responses in isotype-specific fashion within 48 h. These studies also showed that SP, but not neurotensin (NT), serotonin (5-HT), somatostatin (SOM) or gastrin, suppressed BPO-specific memory IgE antibody-forming cell (AFC) responses induced in vitro, also in isotype-specific fashion. To investigate the mechanisms by which SP suppressed BPO-specific IgE AFC responses were induced in vitro, these responses were induced by culturing spleen cells from BPO-KLH sensitized mice for 5 days with BPO-KLH with or without whole SP, amino terminal SP (SP 1-4: Arg-Lys-Pro-Lys), or carboxy terminal SP (SP 8-11: Phe-Gly-Leu-Met). In some experiments, the SP receptor antagonist (D-Pro2, D-Phe7, D-Trp9)-SP (D-SP) was included in culture. In other experiments anti-interferon monoclonal antibody (anti-IFN gamma mAb) was in culture. Whole SP and SP 8-11, but not SP 1-4, suppressed BPO-specific IgE AFC responses induced in vitro. The suppression obtained was IgE isotype-specific and dose-dependent. Inclusion of SP receptor antagonist (D-Pro2, D-Phe7, D-Trp9)-SP inhibited suppression of BPO-specific memory IgE AFC responses by SP or SP 8-11. The SP-mediated suppression of BPO-specific memory IgE responses appeared to involve interferon gamma (IFN gamma).

  15. Antibody-mediated targeting of iron oxide nanoparticles to the folate receptor alpha increases tumor cell association in vitro and in vivo

    Science.gov (United States)

    Ndong, Christian; Toraya-Brown, Seiko; Kekalo, Katsiaryna; Baker, Ian; Gerngross, Tillman U; Fiering, Steven N; Griswold, Karl E

    2015-01-01

    Active molecular targeting has become an important aspect of nanoparticle development for oncology indications. Here, we describe molecular targeting of iron oxide nanoparticles (IONPs) to the folate receptor alpha (FOLRα) using an engineered antibody fragment (Ffab). Compared to control nanoparticles targeting the non-relevant botulinum toxin, the Ffab-IONP constructs selectively accumulated on FOLRα-overexpressing cancer cells in vitro, where they exhibited the capacity to internalize into intracellular vesicles. Similarly, Ffab-IONPs homed to FOLRα-positive tumors upon intraperitoneal administration in an orthotopic murine xenograft model of ovarian cancer, whereas negative control particles showed no detectable tumor accumulation. Interestingly, Ffab-IONPs built with custom 120 nm nanoparticles exhibited lower in vitro targeting efficiency when compared to those built with commercially sourced 180 nm nanoparticles. In vivo, however, the two Ffab-IONP platforms achieved equivalent tumor homing, although the smaller 120 nm IONPs were more prone to liver sequestration. Overall, the results show that Ffab-mediated targeting of IONPs yields specific, high-level accumulation within cancer cells, and this fact suggests that Ffab-IONPs could have future utility in ovarian cancer diagnostics and therapy. PMID:25878495

  16. Biosimilars in immune-mediated inflammatory diseases: initial lessons from the first approved biosimilar anti-tumour necrosis factor monoclonal antibody.

    Science.gov (United States)

    Isaacs, J D; Cutolo, M; Keystone, E C; Park, W; Braun, J

    2016-01-01

    The introduction of targeted biological therapies has revolutionised the management of immune-mediated inflammatory diseases (IMIDs) such as rheumatoid arthritis, ankylosing spondylitis, psoriasis and inflammatory bowel disease. Following treatment with these therapies, many patients experience significant improvements in different aspects of their disease, including symptoms, work productivity and other outcomes relevant for individuals and society. However, due to the complexity of biological drug development and manufacturing processes, the costs of these therapies are relatively high. Indeed, the financial burden on healthcare systems due to biological therapies is considerable and lack of patient access to effective treatment remains a concern in many parts of the world. As many reference biological therapies have now reached or are near to patent expiry, a number of 'biosimilar' drugs have been developed for use in various clinical settings, and some of these drugs are already in use in several countries. While the potential pharmacoeconomic benefits of cost-effective biosimilars seem clear, several issues have been raised regarding, for example, the definition of biosimilarity and the validity of indication extrapolation, as well as the 'switchability' and relative immunogenicity of biosimilars and their reference drugs. In this review, these issues will be discussed with reference to CT-P13, a biosimilar of the anti-tumour necrosis factor monoclonal antibody infliximab, which is approved in Europe and elsewhere for the treatment of various IMIDs. Other important issues, including those related to data collection during nonclinical and clinical development of biosimilars, are also discussed. PMID:26403380

  17. Non-HLA antibodies against endothelial targets bridging allo- and autoimmunity.

    Science.gov (United States)

    Dragun, Duska; Catar, Rusan; Philippe, Aurélie

    2016-08-01

    Detrimental actions of donor-specific antibodies (DSAs) directed against both major histocompatibility antigens (human leukocyte antigen [HLA]) and specific non-HLA antigens expressed on the allograft endothelium are a flourishing research area in kidney transplantation. Newly developed solid-phase assays enabling detection of functional non-HLA antibodies targeting G protein-coupled receptors such as angiotensin type I receptor and endothelin type A receptor were instrumental in providing long-awaited confirmation of their broad clinical relevance. Numerous recent clinical studies implicate angiotensin type I receptor and endothelin type A receptor antibodies as prognostic biomarkers for earlier occurrence and severity of acute and chronic immunologic complications in solid organ transplantation, stem cell transplantation, and systemic autoimmune vascular disease. Angiotensin type 1 receptor and endothelin type A receptor antibodies exert their pathophysiologic effects alone and in synergy with HLA-DSA. Recently identified antiperlecan antibodies are also implicated in accelerated allograft vascular pathology. In parallel, protein array technology platforms enabled recognition of new endothelial surface antigens implicated in endothelial cell activation. Upon target antigen recognition, non-HLA antibodies act as powerful inducers of phenotypic perturbations in endothelial cells via activation of distinct intracellular cell-signaling cascades. Comprehensive diagnostic assessment strategies focusing on both HLA-DSA and non-HLA antibody responses could substantially improve immunologic risk stratification before transplantation, help to better define subphenotypes of antibody-mediated rejection, and lead to timely initiation of targeted therapies. Better understanding of similarities and dissimilarities in HLA-DSA and distinct non-HLA antibody-related mechanisms of endothelial damage should facilitate discovery of common downstream signaling targets and pave the

  18. The monoclonal antibody Zt/f2 targeting RON receptor tyrosine kinase as potential therapeutics against tumor growth-mediated by colon cancer cells

    Directory of Open Access Journals (Sweden)

    Zhang Rui-Wen

    2011-07-01

    Full Text Available Abstract Background Overexpression of the RON receptor tyrosine kinase contributes to epithelial cell transformation, malignant progression, and acquired drug resistance. RON also has been considered as a potential target for therapeutic intervention. This study determines biochemical features and inhibitory activity of a mouse monoclonal antibody (mAb Zt/f2 in experimental cancer therapy. Results Zt/f2 is a mouse IgG2a mAb that is highly specific and sensitive to human RON and its oncogenic variants such as RON160 (ED50 = 2.3 nmol/L. Receptor binding studies revealed that Zt/f2 interacts with an epitope(s located in a 49 amino acid sequence coded by exon 11 in the RON β-chain extracellular sequences. This sequence is critical in regulating RON maturation and phosphorylation. Zt/f2 did not compete with ligand macrophage-stimulating protein for binding to RON; however, its engagement effectively induced RON internalization, which diminishes RON expression and impairs downstream signaling activation. These biochemical features provide the cellular basis for the use of Zt/f2 to inhibit tumor growth in animal model. Repeated administration of Zt/f2 as a single agent into Balb/c mice results in partial inhibition of tumor growth caused by transformed NIH-3T3 cells expressing oncogenic RON160. Colon cancer HT-29 cell-mediated tumor growth in athymic nude mice also was attenuated following Zt/f2 treatment. In both cases, ~50% inhibition of tumor growth as measured by tumor volume was achieved. Moreover, Zt/f2 in combination with 5-fluorouracil showed an enhanced inhibition effect of ~80% on HT-29 cell-mediated tumor growth in vivo. Conclusions Zt/f2 is a potential therapeutic mAb capable of inhibiting RON-mediated oncogenesis by colon cancer cells in animal models. The inhibitory effect of Zt/f2 in vivo in combination with chemoagent 5-fluorouracil could represent a novel strategy for future colon cancer therapy.

  19. Bortezomib for antibody mediated rejection treatment: experience at the Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán in Mexico City.

    Science.gov (United States)

    Leyva, Sergio; Marino-Vázquez, Lluvia A; Reyes-Loaeza, Jorge A; Vega, Olynka; Uribe-Uribe, Norma; Alberú, Josefina; Morales-Buenrostro, Luis E

    2009-01-01

    The use of bortezomib as a treatment modality of AHR improved and stabilized graft function (clinical response) in the majority of patients. Its use in single dose, even combined with rituximab, does not seem to be useful to obtain a sustained clinical response neither to reduce HLAabs level. The use of 4 doses of bortezomib in days 1, 4, 7, and 10 (1.3 mg/m2 BSA each) plus plasmapheresis produced both a good clinical response and a reduction in DSA. Moving forward, it will necessary to define the long-term effectiveness of bortezomib and whether rituximab administration is indispensable to achieve this goal.

  20. Chronic cardiac rejection: identification of five upregulated genes in transplanted hearts by differential mRNA display.

    OpenAIRE

    Utans, U; Liang, P; Wyner, L R; Karnovsky, M. J.; Russell, M. E.

    1994-01-01

    Transplant arteriosclerosis, the major manifestation of chronic rejection, develops after allogeneic (Lewis to F344) but not syngeneic (Lewis to Lewis) rat cardiac transplantation. To identify transcriptionally regulated mediators associated with chronic cardiac rejection, we adapted the differential mRNA display technique for in vivo transplant specimens. Gene transcript patterns in four allogeneic hearts showing early signs of chronic rejection were compared with those in two syngeneic hear...

  1. Developmental Pathways from Childhood Aggression-Disruptiveness, Chronic Peer Rejection and Deviant Friendships to Early-Adolescent Rule Breaking

    OpenAIRE

    Ettekal, Idean; Ladd, Gary W.

    2014-01-01

    Childhood aggression-disruptiveness, chronic peer rejection, and deviant friendships were examined as predictors of early-adolescent rule breaking behaviors. Using a sample of 383 children (193 girls and 190 boys) who were followed from ages 6 to 14, peer rejection trajectories were identified and incorporated into a series of alternative models to assess how chronic peer rejection and deviant friendships mediate the association between stable childhood aggression-disruptiveness and early-ado...

  2. Antibody-mediated targeted gene transfer of helper virus-free HSV-1 vectors to rat neocortical neurons that contain either NMDA receptor 2B or 2A subunits

    OpenAIRE

    Cao, Haiyan; Zhang, Guo-rong; Geller, Alfred I.

    2011-01-01

    Because of the numerous types of neurons in the brain, and particularly the forebrain, neuron type-specific expression will benefit many potential applications of direct gene transfer. The two most promising approaches for achieving neuron type-specific expression are targeted gene transfer to a specific type of neuron and using a neuron type-specific promoter. We previously developed antibody-mediated targeted gene transfer with Herpes Simplex Virus (HSV-1) vectors by modifying glycoprotein ...

  3. Substitution at aspartic acid 1128 in the SARS coronavirus spike glycoprotein mediates escape from a S2 domain-targeting neutralizing monoclonal antibody.

    Directory of Open Access Journals (Sweden)

    Oi-Wing Ng

    Full Text Available The Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV is the etiological agent for the infectious disease, SARS, which first emerged 10 years ago. SARS-CoV is a zoonotic virus that has crossed the species barriers to infect humans. Bats, which harbour a diverse pool of SARS-like CoVs (SL-CoVs, are believed to be the natural reservoir. The SARS-CoV surface Spike (S protein is a major antigenic determinant in eliciting neutralizing antibody production during SARS-CoV infection. In our previous work, we showed that a panel of murine monoclonal antibodies (mAbs that target the S2 subunit of the S protein are capable of neutralizing SARS-CoV infection in vitro (Lip KM et al, J Virol. 2006 Jan; 80(2: 941-50. In this study, we report our findings on the characterization of one of these mAbs, known as 1A9, which binds to the S protein at a novel epitope within the S2 subunit at amino acids 1111-1130. MAb 1A9 is a broadly neutralizing mAb that prevents viral entry mediated by the S proteins of human and civet SARS-CoVs as well as bat SL-CoVs. By generating mutant SARS-CoV that escapes the neutralization by mAb 1A9, the residue D1128 in S was found to be crucial for its interaction with mAb 1A9. S protein containing the substitution of D1128 with alanine (D1128A exhibited a significant decrease in binding capability to mAb 1A9 compared to wild-type S protein. By using a pseudotyped viral entry assay, it was shown that the D1128A substitution in the escape virus allows it to overcome the viral entry blockage by mAb 1A9. In addition, the D1128A mutation was found to exert no effects on the S protein cell surface expression and incorporation into virion particles, suggesting that the escape virus retains the same viral entry property as the wild-type virus.

  4. Studies of nontarget-mediated distribution of human full-length IgG1 antibody and its FAb fragment in cardiovascular and metabolic-related tissues.

    Science.gov (United States)

    Davidsson, Pia; Söderling, Ann-Sofi; Svensson, Lena; Ahnmark, Andrea; Flodin, Christine; Wanag, Ewa; Screpanti-Sundqvist, Valentina; Gennemark, Peter

    2015-05-01

    Tissue distribution and pharmacokinetics (PK) of full-length nontargeted antibody and its antigen-binding fragment (FAb) were evaluated for a range of tissues primarily of interest for cardiovascular and metabolic diseases. Mice were intravenously injected with a dose of 10 mg/kg of either human IgG1or its FAb fragment; perfused tissues were collected at a range of time points over 3 weeks for the human IgG1 antibody and 1 week for the human FAb antibody. Tissues were homogenized and antibody concentrations were measured by specific immunoassays on the Gyros system. Exposure in terms of maximum concentration (Cmax ) and area under the curve was assessed for all nine tissues. Tissue exposure of full-length antibody relative to plasma exposure was found to be between 1% and 10%, except for brain (0.2%). Relative concentrations of FAb antibody were the same, except for kidney tissue, where the antibody concentration was found to be ten times higher than in plasma. However, the absolute tissue uptake of full-length IgG was significantly higher than the absolute tissue uptake of the FAb antibody. This study provides a reference PK state for full-length whole and FAb antibodies in tissues related to cardiovascular and metabolic diseases that do not include antigen or antibody binding.

  5. Graft-infiltrating host dendritic cells play a key role in organ transplant rejection

    Science.gov (United States)

    Zhuang, Quan; Liu, Quan; Divito, Sherrie J.; Zeng, Qiang; Yatim, Karim M.; Hughes, Andrew D.; Rojas-Canales, Darling M.; Nakao, A.; Shufesky, William J.; Williams, Amanda L.; Humar, Rishab; Hoffman, Rosemary A.; Shlomchik, Warren D.; Oberbarnscheidt, Martin H.; Lakkis, Fadi G.; Morelli, Adrian E.

    2016-01-01

    Successful engraftment of organ transplants has traditionally relied on preventing the activation of recipient (host) T cells. Once T-cell activation has occurred, however, stalling the rejection process becomes increasingly difficult, leading to graft failure. Here we demonstrate that graft-infiltrating, recipient (host) dendritic cells (DCs) play a key role in driving the rejection of transplanted organs by activated (effector) T cells. We show that donor DCs that accompany heart or kidney grafts are rapidly replaced by recipient DCs. The DCs originate from non-classical monocytes and form stable, cognate interactions with effector T cells in the graft. Eliminating recipient DCs reduces the proliferation and survival of graft-infiltrating T cells and abrogates ongoing rejection or rejection mediated by transferred effector T cells. Therefore, host DCs that infiltrate transplanted organs sustain the alloimmune response after T-cell activation has already occurred. Targeting these cells provides a means for preventing or treating rejection. PMID:27554168

  6. Graft-infiltrating host dendritic cells play a key role in organ transplant rejection.

    Science.gov (United States)

    Zhuang, Quan; Liu, Quan; Divito, Sherrie J; Zeng, Qiang; Yatim, Karim M; Hughes, Andrew D; Rojas-Canales, Darling M; Nakao, A; Shufesky, William J; Williams, Amanda L; Humar, Rishab; Hoffman, Rosemary A; Shlomchik, Warren D; Oberbarnscheidt, Martin H; Lakkis, Fadi G; Morelli, Adrian E

    2016-01-01

    Successful engraftment of organ transplants has traditionally relied on preventing the activation of recipient (host) T cells. Once T-cell activation has occurred, however, stalling the rejection process becomes increasingly difficult, leading to graft failure. Here we demonstrate that graft-infiltrating, recipient (host) dendritic cells (DCs) play a key role in driving the rejection of transplanted organs by activated (effector) T cells. We show that donor DCs that accompany heart or kidney grafts are rapidly replaced by recipient DCs. The DCs originate from non-classical monocytes and form stable, cognate interactions with effector T cells in the graft. Eliminating recipient DCs reduces the proliferation and survival of graft-infiltrating T cells and abrogates ongoing rejection or rejection mediated by transferred effector T cells. Therefore, host DCs that infiltrate transplanted organs sustain the alloimmune response after T-cell activation has already occurred. Targeting these cells provides a means for preventing or treating rejection.

  7. Rejection sensitivity and depressive symptoms: Longitudinal actor-partner effects in adolescent romantic relationships.

    Science.gov (United States)

    Norona, Jerika C; Roberson, Patricia N E; Welsh, Deborah P

    2016-08-01

    The present study utilizes the actor-partner interdependence model to examine the longitudinal relationship between rejection sensitivity and one's own and one's partner's depressive symptoms. The sample included adolescent romantic couples from the U.S. (N = 198 adolescents; 50% girls; 90.2% Caucasian) whose rejection sensitivity at Time 1 and depressive symptoms approximately one year later (Time 2) were assessed. Additionally, aggressive behaviors and maintenance behaviors that commonly associated with rejection sensitivity (e.g., self-silencing) are explored as mediators. Results indicate that boyfriends' rejection sensitivity at Time 1 predicted girlfriends' depressive symptoms at Time 2. Additionally, girls' rejection sensitivity predicted their own and their boyfriends' self-silencing. Developmental and clinical implications are discussed. PMID:27254083

  8. Graft-infiltrating host dendritic cells play a key role in organ transplant rejection.

    Science.gov (United States)

    Zhuang, Quan; Liu, Quan; Divito, Sherrie J; Zeng, Qiang; Yatim, Karim M; Hughes, Andrew D; Rojas-Canales, Darling M; Nakao, A; Shufesky, William J; Williams, Amanda L; Humar, Rishab; Hoffman, Rosemary A; Shlomchik, Warren D; Oberbarnscheidt, Martin H; Lakkis, Fadi G; Morelli, Adrian E

    2016-01-01

    Successful engraftment of organ transplants has traditionally relied on preventing the activation of recipient (host) T cells. Once T-cell activation has occurred, however, stalling the rejection process becomes increasingly difficult, leading to graft failure. Here we demonstrate that graft-infiltrating, recipient (host) dendritic cells (DCs) play a key role in driving the rejection of transplanted organs by activated (effector) T cells. We show that donor DCs that accompany heart or kidney grafts are rapidly replaced by recipient DCs. The DCs originate from non-classical monocytes and form stable, cognate interactions with effector T cells in the graft. Eliminating recipient DCs reduces the proliferation and survival of graft-infiltrating T cells and abrogates ongoing rejection or rejection mediated by transferred effector T cells. Therefore, host DCs that infiltrate transplanted organs sustain the alloimmune response after T-cell activation has already occurred. Targeting these cells provides a means for preventing or treating rejection. PMID:27554168

  9. The difference of ELISA and LABScreen in detecting HLA antibodies

    Institute of Scientific and Technical Information of China (English)

    吴萍萍

    2013-01-01

    Objective To compare the difference of ELISA and LABScreen in detecting HLA antibodies and evaluate their effects on allograft rejection.Methods Consecutive patients undergoing kidney transplantion from November,2008 to December,2009 in the First Affiliated Hospital

  10. Suppression of natural killer cell activity by rabbit antibody to human beta 2-microglobulin (beta 2m) is an Fc-mediated phenomenon and is not beta 2m specific.

    Science.gov (United States)

    Jones, R A; Richards, S J; Patel, D; Scott, C S

    1991-07-01

    Natural killer (NK) cell cytotoxicity constitutes an important component of the host immune defence system. The NK effector cell has been relatively well defined in terms of immunophenotypic characteristics, but in contrast to the functional T-cell receptor molecule associated with major histocompatibility complex (MHC)-restricted cytotoxic activity, the NK cell receptor has not to date been defined. However, several studies have suggested that the beta 2-microglobulin (beta 2m) molecule is functionally associated with NK cell activity. Using various heterospecific and monoclonal antibodies, this study has shown that intact rabbit IgG antibody bound either directly or indirectly to peripheral mononuclear cell (PMNC) effector populations significantly reduced their lytic activity against K562 targets. Substitution of F(ab)2 fragments for rabbit IgG antibodies, or the use of monoclonal antibodies alone, failed to reduce peripheral blood mononuclear cell (PMNC) lytic activity. Addition of non-NK cell components labelled with rabbit anti-beta 2m to purified NK-enriched effector cell populations also suppressed K562 lysis. In contrast, pre-treatment of a NK-enriched PMNC fraction with rabbit anti-beta 2m enhanced target lysis. These results strongly suggest that antibody-induced suppression of PMNC NK activity is mediated via rabbit Fc attached to co-existing non-NK cells in the mononuclear fraction, and are inconsistent with the previously suggested functional association between NK activity and membrane beta 2m.

  11. Urinary granzyme A mRNA is a biomarker to diagnose subclinical and acute cellular rejection in kidney transplant recipients

    NARCIS (Netherlands)

    S.M. Ham; K.M. Heutinck; T. Jorritsma; F.J. Bemelman; M.C.M. Strik; W. Vos; J.J.F. Muris; S. Florquin; R.J.M. ten Berge; A.T. Rowshani

    2010-01-01

    The distinction between T-cell-mediated rejection (TCMR) and other causes of kidney transplant dysfunction such as tubular necrosis requires biopsy. Subclinical rejection (SCR), an established risk factor for chronic allograft dysfunction, can only be diagnosed by protocol biopsy. A specific non-inv

  12. EXPRESSION OF ICAM-1 AND LFA-1 MOLECULES IN RELATION TO RENAL ALLOGRAFT REJECTION IN RATS

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Objective.The purpose of this study was to assess the renal graft expression of ICAM-1(intercellular adhesion molecule-1) nd LFA-1(lymphocyte function-associated antigen-1)molecule with relation to graft rejection.Methods.Rat kiney transplantation was performed according to the procedure of Kamada with some modification.Experimental rats were divided into 5 groups.The survival time of recipient rats and function of grafts after renal transplantation were observed.The sections of renal graft were stained for monoclonal antibody ICAM-1 and LFA-1, and then quantification of ICAM-1 and LFA-1 expression was accomplished by computer image analysis.Results.ICAM-1 and LFA-1 increased significantly in the renal allograft rejection group as compared with the non-rejection groups(P<0.05).Conluson.Both biopsy of renal graft and monitoring of ICAM-1 and LFA-1 are useful tools in diagnosing and treating acute rejection.

  13. Comparing reports of peer rejection: associations with rejection sensitivity, victimization, aggression, and friendship.

    Science.gov (United States)

    Zimmer-Gembeck, Melanie J; Nesdale, Drew; McGregor, Leanne; Mastro, Shawna; Goodwin, Belinda; Downey, Geraldine

    2013-12-01

    Perceiving that one is rejected is an important correlate of emotional maladjustment. Yet, self-perceptions can substantially differ from classmate-reports of who is rejected. In this study, discrepancies between self- and classmate-reports of rejection were identified in 359 Australian adolescents (age 10-12 years). As expected, adolescents who overestimated rejection reported more rejection sensitivity and felt more victimized by their peers, but were not seen by peers as more victimized. Adolescents who underestimated rejection identified themselves as high in overt aggression, and their peers identified them as high in overt and relational aggression and low in prosocial behavior. Yet, underestimators' feelings of friendship satisfaction did not seem to suffer and they reported low rejection sensitivity. Results suggest that interventions to promote adolescent health should explicitly recognize the different needs of those who do and do not seem to perceive their high rejection, as well as adolescents who overestimate their rejection. PMID:24215970

  14. Mediation as Signal

    OpenAIRE

    Holler, M.J.; Lindner, I.

    2004-01-01

    This paper analyzes mediation as a signal. Starting from a stylized case, a game theoretical model of one-sided incomplete information, taken from Cho and Kreps (1987), is applied to discuss strategic effects of mediation. It turns out that to reject mediation can be interpreted as a ”negative signal” while the interpretation of accepting or proposing mediation is ambiguous and does not necessarily change the prior beliefs of the uninformed party. This asymmetry suggests that, in equilibrium,...

  15. Parental Rejection Following Sexual Orientation Disclosure: Impact on Internalized Homophobia, Social Support, and Mental Health.

    Science.gov (United States)

    Puckett, Julia A; Woodward, Eva N; Mereish, Ethan H; Pantalone, David W

    2015-09-01

    Sexual minority individuals face unique stressors because of their sexual identity. We explored associations between parental reactions to children's coming out, internalized homophobia (IH), social support, and mental health in a sample of 257 sexual minority adults. Path analyses revealed that higher IH and lower social support mediated the association between past parental rejection and current psychological distress. Mental health providers may benefit clients by utilizing interventions that challenge internalized stereotypes about homosexuality, increase social support, and process parental rejection, as well as focusing on how certain crucial experiences of rejection may impact clients' IH and mental health.

  16. Renal allograft rejection: sonography and scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Singh, A.; Cohen, W.N.

    1980-07-01

    A total of 30 renal allograft patients who had sonographic B scanning and radionuclide studies of the transplant was studied as to whether: (1) the allograft rejection was associated with any consistent and reliable sonographic features and (2) the sonograms complemented the radionuclide studies. Focal areas of decreased parenchymal echogenicity were the most striking and consistent sonographic finding in chymal echogenicity were the most striking and consistens sonographic finding in allograft rejection. This was observed in most of the patients exhibiting moderate or severe rejection, but was frequently absent with mild rejection. Areas of decreased parenchymal echogenicity were not seen during episodes of acute tubular necrosis. Therefore, sonography showing zones of decreased parenchymal echogenicity was complementary to radionuclide studies in the diagnosis of allograft rejection versus acute tubular necrosis. Corticomedullary demarcation was difficult to interpret because of technical variables, and was inconsistently related to rejection in this series.

  17. Effect of nifedipine on renal transplant rejection.

    Science.gov (United States)

    Nicholson, M L; Dennis, M J; Beckingham, I J; Smith, S J

    1993-10-01

    The effect of early nifedipine therapy on acute renal allograft rejection was studied in 170 adult cadaveric transplant recipients. Acute rejection occurring in the first 3 months after transplantation was diagnosed by Tru-cut biopsy and the severity of each rejection episode assessed histologically. The incidence of acute rejection was significantly lower in patients treated with nifedipine (29 of 80; 36 per cent) than in controls (52 of 90; 58 per cent) (P nifedipine exerted a significant independent effect on the incidence of early acute rejection. Other factors identified in the multivariate model as influencing rejection were human leucocyte antigen (HLA) matching at the DR locus, blood level of cyclosporin during the first week, HLA matching at the B locus, donor age and donor sex. The 1-year graft survival rate was 88.6 per cent in patients given nifedipine and 63.8 per cent in controls (P nifedipine therapy has a useful role in human renal transplantation.

  18. Insights from computational modeling in inflammation and acute rejection in limb transplantation.

    Science.gov (United States)

    Wolfram, Dolores; Starzl, Ravi; Hackl, Hubert; Barclay, Derek; Hautz, Theresa; Zelger, Bettina; Brandacher, Gerald; Lee, W P Andrew; Eberhart, Nadine; Vodovotz, Yoram; Pratschke, Johann; Pierer, Gerhard; Schneeberger, Stefan

    2014-01-01

    Acute skin rejection in vascularized composite allotransplantation (VCA) is the major obstacle for wider adoption in clinical practice. This study utilized computational modeling to identify biomarkers for diagnosis and targets for treatment of skin rejection. Protein levels of 14 inflammatory mediators in skin and muscle biopsies from syngeneic grafts [n = 10], allogeneic transplants without immunosuppression [n = 10] and allografts treated with tacrolimus [n = 10] were assessed by multiplexed analysis technology. Hierarchical Clustering Analysis, Principal Component Analysis, Random Forest Classification and Multinomial Logistic Regression models were used to segregate experimental groups. Based on Random Forest Classification, Multinomial Logistic Regression and Hierarchical Clustering Analysis models, IL-4, TNF-α and IL-12p70 were the best predictors of skin rejection and identified rejection well in advance of histopathological alterations. TNF-α and IL-12p70 were the best predictors of muscle rejection and also preceded histopathological alterations. Principal Component Analysis identified IL-1α, IL-18, IL-1β, and IL-4 as principal drivers of transplant rejection. Thus, inflammatory patterns associated with rejection are specific for the individual tissue and may be superior for early detection and targeted treatment of rejection. PMID:24926998

  19. LATE RENAL GRAFT REJECTION: PATHOLOGY AND PROGNOSIS

    Directory of Open Access Journals (Sweden)

    E.S. Stolyarevich

    2014-01-01

    Full Text Available Rejection has always been one of the most important cause of late renal graft dysfunction. Aim of the study was to analyze the prevalence of different clinico-pathological variants of rejection that cause late graft dysfunction, and evaluate their impact on long-term outcome. Materials and methods. This is a retrospective study that analyzed 294 needle core biopsy specimens from 265 renal transplant recipients with late (48,8 ± 46,1 months after transplantation allograft dysfunction caused by late acute rejection (LAR, n = 193 or chronic rejection (CR, n = 78 or both (n = 23. C4d staining was performed by immunofl uorescence (IF on frozen sections using a standard protocol. Results. Peritubular capillary C4d deposition was identifi ed in 36% samples with acute rejection and in 62% cases of chronic rejection (including 67% cases of transplant glomerulopathy, and 50% – of isolated chronic vasculopathy. 5-year graft survival for LAR vs CR vs their combination was 47, 13 and 25%, respectively. The outcome of C4d– LAR was (p < 0,01 better than of C4d+ acute rejection: at 60 months graft survival for diffuse C4d+ vs C4d− was 33% vs 53%, respectively. In cases of chronic rejection C4d+ vs C4d– it was not statistically signifi cant (34% vs 36%. Conclusion. In long-term allograft biopsy C4d positivity is more haracteristic for chronic rejection than for acute rejection. Only diffuse C4d staining affects the outcome. C4d– positivity is associated with worse allograft survival in cases of late acute rejection, but not in cases of chronic rejection

  20. Split Rejection in Vascularized Composite Allotransplantation

    OpenAIRE

    Sinha, Indranil; Pomahac, Bohdan

    2013-01-01

    Introduction: Graft monitoring following vascularized composite allotransplantation (VCA) relies primarily on serial skin biopsy. However, given that VCA comprised multiple tissue types, skin biopsy may not accurately reflect rejection in other transplanted tissue. Methods: A review of the literature on episodes of both acute and chronic rejection following VCA was completed. Special attention was given to how these patients were monitored for rejection and whether skin biopsy accurately refl...

  1. Aberrantly glycosylated MUC1 is expressed on the surface of breast cancer cells and a target for antibody-dependent cell-mediated cytotoxicity

    DEFF Research Database (Denmark)

    Lavrsen, Kirstine; Madsen, Caroline B; Rasch, Morten G;

    2013-01-01

    not covered by immunological tolerance in MUC1 humanized mice and man. The objective of this study was to determine if mouse antibodies to this Tn-MUC1 epitope induce antibody-dependent cellular cytotoxicity (ADCC) pivotal for their potential use in cancer immunotherapy. Binding affinity of mAb 5E5 directed...

  2. CHO-S antibody titers >1 gram/liter using flow electroporation-mediated transient gene expression followed by rapid migration to high-yield stable cell lines.

    Science.gov (United States)

    Steger, Krista; Brady, James; Wang, Weili; Duskin, Meg; Donato, Karen; Peshwa, Madhusudan

    2015-04-01

    In recent years, researchers have turned to transient gene expression (TGE) as an alternative to CHO stable cell line generation for early-stage antibody development. Despite advances in transfection methods and culture optimization, the majority of CHO-based TGE systems produce insufficient antibody titers for extensive use within biotherapeutic development pipelines. Flow electroporation using the MaxCyte STX Scalable Transfection System is a highly efficient, scalable means of CHO-based TGE for gram-level production of antibodies without the need for specialized expression vectors or genetically engineered CHO cell lines. CHO cell flow electroporation is easily scaled from milligram to multigram quantities without protocol reoptimization while maintaining transfection performance and antibody productivity. In this article, data are presented that demonstrate the reproducibility, scalability, and antibody production capabilities of CHO-based TGE using the MaxCyte STX. Data show optimization of posttransfection parameters such as cell density, media composition, and feed strategy that result in secreted antibody titers >1 g/L and production of multiple grams of antibody within 2 weeks of a single CHO-S cell transfection. In addition, data are presented to demonstrate the application of scalable electroporation for the rapid generation of high-yield stable CHO cell lines to bridge the gap between early- and late-stage antibody development activities.

  3. Cellular basis of allograft rejection in vivo. III. Restoration of first-set rejection of heart grafts by T helper cells in irradiated rats

    Energy Technology Data Exchange (ETDEWEB)

    Hall, B.M.; de Saxe, I.; Dorsch, S.E.

    1983-12-01

    An adoptive transfer model was used to examine the subpopulations of lymphocytes required to effect first-set rejection of directly vascularized heart allografts. PVG heart grafts are not rejected in irradiated DA hosts for at least 50 days. The adoptive transfer of 5 X 10(7) syngeneic lymph node cells (LNC) restores rejection to 14.4 +/- 2.4 days (mean +/- SD). Subpopulations of LNC, were separated by an indirect ''panning'' technique using the mouse antirat monoclonal antibodies W3/13, MRC OX8, or W3/25 to deplete the unwanted subsets of cells. Each subpopulation was tested, in a number equivalent to the number present in 5 X 10(7) normal LNC, for its ability to cause the rejection of heart grafts. Whole T cells (W3/13+) or helper/inducer T cells (W3/25+) restored graft rejection to 16.4 +/- 3.8 d and 16.0 +/- 2.4 days, respectively. Neither cytotoxic/suppressor T cells (MRC OX8+) nor B cells (Ig+) restored rejection. Indirect immunoperoxidase stains of the grafts showed that although W3/25+ cells predominated in the rejected tissue, MRC OX8+ cells were also present even in grafts from rats restored with inocula that contained less than 1% MRC OX8+ cells. Examination of lymphoid tissues suggested that the MRC OX8+ cells might be of host origin. By the time the grafts were rejected in irradiated hosts, significant thymic regeneration had occurred and there were large numbers of MRC OX8+ cells present in the thymus, as well as some in lymph nodes and spleen.

  4. [Chronic rejection: Differences and similarities in various solid organ transplants].

    Science.gov (United States)

    Suhling, H; Gottlieb, J; Bara, C; Taubert, R; Jäckel, E; Schiffer, M; Bräsen, J H

    2016-01-01

    In this paper, chronic rejections after transplantation of the lungs, heart, liver, and kidney are described. Chronic allograft dysfunction (CAD) plays an important role in all of these transplantations and has a significant influence on patient survival. The pathophysiological reasons for CAD varies greatly in the various organs.Chronic lung allograft dysfunction (CLAD) is the most important determinant of survival and quality of life after lung transplantation. Diagnosis is based on lung function, especially forced expiratory flow in 1 s (FEV1) decline. Prevention, early detection, and rapid treatment are extremely important. Azithromycin and extracorporeal photopheresis are commonly used for treatment because they usually positively influence the progression of lung remodeling.The expression for chronic rejection of the heart is cardiac allograft vasculopathy (CAV). Immunological and nonimmunological factors are important for its development. Due to limited therapeutic options, prevention is of utmost importance (administration of mTOR inhibitors and minimizing cardiovascular risk factors).The mid- and long-term survival rates after liver transplantation have hardly changed in recent decades, which is an indication of the difficulty in diagnosing chronic graft dysfunction. Chronic ductopenic rejection accounts for a small proportion of late graft dysfunction. Idiopathic posttransplant hepatitis and de novo autoimmune hepatitis are important in addition to recurrence of the underlying disease that led to transplantation.Chronic allograft nephropathy is the result of severe rejection which cumulates in increasing fibrosis with remodeling. The earliest possible diagnosis and therapy is currently the only option. Diagnosis is based on evidence of donor-specific antibodies and histological findings.

  5. Are You Being Rejected or Excluded? Insights from Neuroimaging Studies Using Different Rejection Paradigms

    OpenAIRE

    Premkumar, Preethi

    2012-01-01

    Rejection sensitivity is the heightened tendency to perceive or anxiously expect disengagement from others during social interaction. There has been a recent wave of neuroimaging studies of rejection. The aim of the current review was to determine key brain regions involved in social rejection by selectively reviewing neuroimaging studies that employed one of three paradigms of social rejection, namely social exclusion during a ball-tossing game, evaluating feedback about preference from peer...

  6. Not all rejections are alike; competence and warmth as a fundamental distinction in social rejection

    NARCIS (Netherlands)

    Celik, P.; Lammers, J.; Beest, I. van; Bekker, M.H.J.; Vonk, R.

    2013-01-01

    Social rejection can lead to a variety of emotions. Two studies show that specific emotional reactions to social rejection can be understood by relying on the fundamental distinction between competence and warmth. Rejection that is perceived to be due to incompetence leads to anger, whereas rejectio

  7. Cationic liposomes enhance targeted delivery and expression of exogenous DNA mediated by N-terminal modified poly(L-lysine)-antibody conjugate in mouse lung endothelial cells.

    Science.gov (United States)

    Trubetskoy, V S; Torchilin, V P; Kennel, S; Huang, L

    1992-07-15

    A new and improved system for targeted gene delivery and expression is described. Transfection efficiency of N-terminal modified poly(L-lysine) (NPLL) conjugated with anti-thrombomodulin antibody 34A can be improved by adding to the system a lipophilic component, cationic liposomes. DNA, antibody conjugate and cationic liposomes form a ternary electrostatic complex which preserves the ability to bind specifically to the target cells. At the same time the addition of liposomes enhance the specific transfection efficiency of antibody-polylysine/DNA binary complex by 10 to 20-fold in mouse lung endothelial cells in culture.

  8. Efficacy of mycofenolate mofetil for steroid-resistant acute rejection after living donor liver transplantation

    Institute of Scientific and Technical Information of China (English)

    Nobuhisa Akamatsu; Yasuhiko Sugawara; Sumihito Tamura; Yuichi Matsui; Junichi Kaneko; Masatoshi Makuuchi

    2006-01-01

    AIM: To discuss the use of mycophenolate mofetil (MMF) as an immunosuppressant in steroid resistant rejection after liver transplantation. METHODS: The clinical records of 260 adult patients who underwent living donor liver transplantation (LDLT) were reviewed. Tacrolimus and methylprednisolone were used for primary immunosuppression. Acute rejection was first treated with steroids. When steroid resistance occurred, the patient was treated with a combination of steroids and MMF. Anti-T-cell monoclonal antibody was administered to patients who were not responsive to steroids in combination with MMF.RESULTS: A total of 90 (35%) patients developed acute rejection. The median interval time from transplantation to the first episode was 15 d. Fifty-four patients were steroid resistant. Forty-four patients were treated with MMF and the remaining 10 required anti-T-cell monoclonal antibody treatment. Progression to chronic rejection was observed in one patient. Bone marrow suppression and gastrointestinal symptoms were the most common side effects associated with MMF use. There was no significant increase in opportunistic infections. CONCLUSION: Our results demonstrate that MMF is a potent and safe immunosuppressive agent for rescue therapy in patients with acute rejection after LDLT.

  9. An adaptive algorithm for noise rejection.

    Science.gov (United States)

    Lovelace, D E; Knoebel, S B

    1978-01-01

    An adaptive algorithm for the rejection of noise artifact in 24-hour ambulatory electrocardiographic recordings is described. The algorithm is based on increased amplitude distortion or increased frequency of fluctuations associated with an episode of noise artifact. The results of application of the noise rejection algorithm on a high noise population of test tapes are discussed.

  10. 21 CFR 1230.47 - Rejected containers.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Rejected containers. 1230.47 Section 1230.47 Food... FEDERAL CAUSTIC POISON ACT Imports § 1230.47 Rejected containers. (a) In all cases where the containers... notification to the importer that the containers must be exported under customs supervision within 3...

  11. Renal allograft rejection. Unusual scintigraphic findings

    Energy Technology Data Exchange (ETDEWEB)

    Desai, A.G.; Park, C.H.

    1986-11-01

    During sequential renal imagining for evaluation of clinically suspected rejection, focal areas of functioning renal tissue were seen in two cases of renal transplant in the midst of severe and irreversible renal allograft rejection. A probable explanation for this histopathologically confirmed and previously unreported finding is discussed.

  12. HIV-1 tat promotes integrin-mediated HIV transmission to dendritic cells by binding Env spikes and competes neutralization by anti-HIV antibodies.

    Directory of Open Access Journals (Sweden)

    Paolo Monini

    Full Text Available Use of Env in HIV vaccine development has been disappointing. Here we show that, in the presence of a biologically active Tat subunit vaccine, a trimeric Env protein prevents in monkeys virus spread from the portal of entry to regional lymph nodes. This appears to be due to specific interactions between Tat and Env spikes that form a novel virus entry complex favoring R5 or X4 virus entry and productive infection of dendritic cells (DCs via an integrin-mediated pathway. These Tat effects do not require Tat-transactivation activity and are blocked by anti-integrin antibodies (Abs. Productive DC infection promoted by Tat is associated with a highly efficient virus transmission to T cells. In the Tat/Env complex the cysteine-rich region of Tat engages the Env V3 loop, whereas the Tat RGD sequence remains free and directs the virus to integrins present on DCs. V2 loop deletion, which unshields the CCR5 binding region of Env, increases Tat/Env complex stability. Of note, binding of Tat to Env abolishes neutralization of Env entry or infection of DCs by anti-HIV sera lacking anti-Tat Abs, which are seldom present in natural infection. This is reversed, and neutralization further enhanced, by HIV sera containing anti-Tat Abs such as those from asymptomatic or Tat-vaccinated patients, or by sera from the Tat/Env vaccinated monkeys. Thus, both anti-Tat and anti-Env Abs are required for efficient HIV neutralization. These data suggest that the Tat/Env interaction increases HIV acquisition and spreading, as a mechanism evolved by the virus to escape anti-Env neutralizing Abs. This may explain the low effectiveness of Env-based vaccines, which are also unlikely to elicit Abs against new Env epitopes exposed by the Tat/Env interaction. As Tat also binds Envs from different clades, new vaccine strategies should exploit the Tat/Env interaction for both preventative and therapeutic interventions.

  13. Image rejects/retakes-radiographic challenges

    International Nuclear Information System (INIS)

    A general held position among radiological personnel prior to digitalisation was that the problem of image rejects/retakes should more or less vanish. However, rejects/retakes still impose several challenges within radiographic imaging; they occupy unnecessary resources, expose patients to unnecessary ionizing radiation and may also indicate suboptimal quality management. The latter is the main objective of this paper, which is based on a survey of international papers published both for screen/film and digital technology. The digital revolution in imaging seems to have reduced the percentage of image rejects/retakes from 10-15 to 3-5%. The major contribution to the decrease appears to be the dramatic reduction of incorrect exposures. At the same time, rejects/retakes due to lack of operator competence (positioning, etc.) are almost unchanged, or perhaps slightly increased (due to lack of proper technical competence, incorrect organ coding, etc.). However, the causes of rejects/retakes are in many cases defined and reported with reference to radiographers' subjective evaluations. Thus, unless radiographers share common views on image quality and acceptance criteria, objective measurements and assessments of reject/retake rates are challenging tasks. Interestingly, none of the investigated papers employs image quality parameters such as 'too much noise' as categories for rejects/retakes. Surprisingly, no reject/retake analysis seems yet to have been conducted for direct digital radiography departments. An increased percentage of rejects/retakes is related to 'digital skills' of radiographers and therefore points to areas for extended education and training. Furthermore, there is a need to investigate the inter subjectivity of radiographers' perception of, and attitude towards, both technical and clinical image quality criteria. Finally, there may be a need to validate whether reject/retake rate analysis is such an effective quality indicator as has been asserted

  14. Image rejects/retakes--radiographic challenges.

    Science.gov (United States)

    Waaler, D; Hofmann, B

    2010-01-01

    A general held position among radiological personnel prior to digitalisation was that the problem of image rejects/retakes should more or less vanish. However, rejects/retakes still impose several challenges within radiographic imaging; they occupy unnecessary resources, expose patients to unnecessary ionizing radiation and may also indicate suboptimal quality management. The latter is the main objective of this paper, which is based on a survey of international papers published both for screen/film and digital technology. The digital revolution in imaging seems to have reduced the percentage of image rejects/retakes from 10-15 to 3-5 %. The major contribution to the decrease appears to be the dramatic reduction of incorrect exposures. At the same time, rejects/retakes due to lack of operator competence (positioning, etc.) are almost unchanged, or perhaps slightly increased (due to lack of proper technical competence, incorrect organ coding, etc.). However, the causes of rejects/retakes are in many cases defined and reported with reference to radiographers' subjective evaluations. Thus, unless radiographers share common views on image quality and acceptance criteria, objective measurements and assessments of reject/retake rates are challenging tasks. Interestingly, none of the investigated papers employs image quality parameters such as 'too much noise' as categories for rejects/retakes. Surprisingly, no reject/retake analysis seems yet to have been conducted for direct digital radiography departments. An increased percentage of rejects/retakes is related to 'digital skills' of radiographers and therefore points to areas for extended education and training. Furthermore, there is a need to investigate the inter-subjectivity of radiographers' perception of, and attitude towards, both technical and clinical image quality criteria. Finally, there may be a need to validate whether reject/retake rate analysis is such an effective quality indicator as has been asserted

  15. The Early Protective Thymus-Independent Antibody Response to Foot-and-Mouth Disease Virus Is Mediated by Splenic CD9+ B Lymphocytes▿

    OpenAIRE

    Ostrowski, Matias; Vermeulen, Monica; Zabal, Osvaldo; Zamorano, Patricia I; Sadir, Ana M; Jorge R. Geffner; Lopez, Osvaldo J.

    2007-01-01

    Infection of mice with cytopathic foot-and-mouth disease virus (FMDV) induces a rapid and specific thymus-independent (TI) neutralizing antibody response that promptly clears the virus. Herein, it is shown that FMDV-infected dendritic cells (DCs) directly stimulate splenic innate-like CD9+ B lymphocytes to rapidly (3 days) produce neutralizing anti-FMDV immunoglobulin M antibodies without T-lymphocyte collaboration. In contrast, neither follicular (CD9−) B lymphocytes from the spleen nor B ly...

  16. Relative Contribution of Dengue IgG Antibodies Acquired during Gestation or Breastfeeding in Mediating Dengue Disease Enhancement and Protection in Type I Interferon Receptor-Deficient Mice.

    Science.gov (United States)

    Lee, Pei Xuan; Ong, Li Ching; Libau, Eshele Anak; Alonso, Sylvie

    2016-06-01

    Dengue virus (DENV) causes a spectrum of diseases ranging from self-limiting dengue fever to severe conditions such as haemorrhagic fever and dengue shock syndrome. Antibody-dependent enhancement (ADE) is thought to explain the occurrence of severe dengue whereby pre-existing binding but non-neutralising antibodies enhance DENV infection. The ADE phenomenon is supported by epidemiological findings that infants that born to dengue immune mothers are at greater risk to develop severe dengue upon primary infection. The role of maternally acquired dengue-specific antibodies in disease enhancement was recently recapitulated in a mouse model where mice born to DENV1-immune mothers experienced enhanced disease severity upon DENV2 infection. Here, this study investigates the relative contribution of maternal dengue-specific antibodies acquired during gestation and breastfeeding in dengue disease. Using a surrogate breastfeeding mother experimental approach, we showed that majority of the maternal dengue-specific antibodies were acquired during breastfeeding and conferred an extended enhancement window. On the other hand, in the context of homologous infection, breastfeeding conferred protection. Furthermore, measurement of dengue-specific antibody titres over time in mice born to dengue immune mothers revealed a biphasic pattern of antibody decay as reported in humans. Our work provides evidence of the potential contribution of breast milk-acquired dengue-specific IgG antibodies in enhancement and protection against dengue. Should such contribution be established in humans as well, it may have important implications for the development of guidelines to dengue-immune breastfeeding mothers. PMID:27341339

  17. Relative Contribution of Dengue IgG Antibodies Acquired during Gestation or Breastfeeding in Mediating Dengue Disease Enhancement and Protection in Type I Interferon Receptor-Deficient Mice.

    Directory of Open Access Journals (Sweden)

    Pei Xuan Lee

    2016-06-01

    Full Text Available Dengue virus (DENV causes a spectrum of diseases ranging from self-limiting dengue fever to severe conditions such as haemorrhagic fever and dengue shock syndrome. Antibody-dependent enhancement (ADE is thought to explain the occurrence of severe dengue whereby pre-existing binding but non-neutralising antibodies enhance DENV infection. The ADE phenomenon is supported by epidemiological findings that infants that born to dengue immune mothers are at greater risk to develop severe dengue upon primary infection. The role of maternally acquired dengue-specific antibodies in disease enhancement was recently recapitulated in a mouse model where mice born to DENV1-immune mothers experienced enhanced disease severity upon DENV2 infection. Here, this study investigates the relative contribution of maternal dengue-specific antibodies acquired during gestation and breastfeeding in dengue disease. Using a surrogate breastfeeding mother experimental approach, we showed that majority of the maternal dengue-specific antibodies were acquired during breastfeeding and conferred an extended enhancement window. On the other hand, in the context of homologous infection, breastfeeding conferred protection. Furthermore, measurement of dengue-specific antibody titres over time in mice born to dengue immune mothers revealed a biphasic pattern of antibody decay as reported in humans. Our work provides evidence of the potential contribution of breast milk-acquired dengue-specific IgG antibodies in enhancement and protection against dengue. Should such contribution be established in humans as well, it may have important implications for the development of guidelines to dengue-immune breastfeeding mothers.

  18. Relative Contribution of Dengue IgG Antibodies Acquired during Gestation or Breastfeeding in Mediating Dengue Disease Enhancement and Protection in Type I Interferon Receptor-Deficient Mice.

    OpenAIRE

    Pei Xuan Lee; Li Ching Ong; Eshele Anak Libau; Sylvie Alonso

    2016-01-01

    Dengue virus (DENV) causes a spectrum of diseases ranging from self-limiting dengue fever to severe conditions such as haemorrhagic fever and dengue shock syndrome. Antibody-dependent enhancement (ADE) is thought to explain the occurrence of severe dengue whereby pre-existing binding but non-neutralising antibodies enhance DENV infection. The ADE phenomenon is supported by epidemiological findings that infants that born to dengue immune mothers are at greater risk to develop severe dengue upo...

  19. Relative Contribution of Dengue IgG Antibodies Acquired during Gestation or Breastfeeding in Mediating Dengue Disease Enhancement and Protection in Type I Interferon Receptor-Deficient Mice

    Science.gov (United States)

    Lee, Pei Xuan; Ong, Li Ching; Libau, Eshele Anak; Alonso, Sylvie

    2016-01-01

    Dengue virus (DENV) causes a spectrum of diseases ranging from self-limiting dengue fever to severe conditions such as haemorrhagic fever and dengue shock syndrome. Antibody-dependent enhancement (ADE) is thought to explain the occurrence of severe dengue whereby pre-existing binding but non-neutralising antibodies enhance DENV infection. The ADE phenomenon is supported by epidemiological findings that infants that born to dengue immune mothers are at greater risk to develop severe dengue upon primary infection. The role of maternally acquired dengue-specific antibodies in disease enhancement was recently recapitulated in a mouse model where mice born to DENV1-immune mothers experienced enhanced disease severity upon DENV2 infection. Here, this study investigates the relative contribution of maternal dengue-specific antibodies acquired during gestation and breastfeeding in dengue disease. Using a surrogate breastfeeding mother experimental approach, we showed that majority of the maternal dengue-specific antibodies were acquired during breastfeeding and conferred an extended enhancement window. On the other hand, in the context of homologous infection, breastfeeding conferred protection. Furthermore, measurement of dengue-specific antibody titres over time in mice born to dengue immune mothers revealed a biphasic pattern of antibody decay as reported in humans. Our work provides evidence of the potential contribution of breast milk-acquired dengue-specific IgG antibodies in enhancement and protection against dengue. Should such contribution be established in humans as well, it may have important implications for the development of guidelines to dengue-immune breastfeeding mothers. PMID:27341339

  20. PREVENTION AND TREATMENT OF REJECTION AFTER SIMULTANEOUS PANCREAS-KIDNEY TRANSPLANTATION

    Institute of Scientific and Technical Information of China (English)

    Lei Yang; Yong-feng Liu; Shu-rong Liu; Gang Wu; Jia-lin Zhang; Yi-man Meng; Shao-wei Shong; Gui-chen Li

    2005-01-01

    Objective To explore methods of preventing and reversing rejection after simultaneous pancreas-kidney (SPK) tran splantation. Methods Seventeen patients underwent SPK transplantation from September 1999 to September 2003 were reviewed retrospectively. Immunosuppression was achieved by a triple drug regimen consisting of cyclosporine, mycophenolate mofteil (MMF), and steroids. Three patients were treated with anti-CD3 monoclone antibody (OKT3, 5 mg· d-1) for induction therapy for a mean period of 5-7 days. One patients received IL-2 receptor antibodies (daclizumab) in a dose of 1 mg· kg-1 on the day of transplant and the 5th day posttransplant. One patient was treated with both OKT3 and daclizumab for induction. Results No primary non-functionality of either kidney or pancreas occurred in this series of transplantations. Function of all the kidney grafts recovered within 2 to 4 days after transplantation. The level of serum creatinine was 94 ± 11 μmol/L on the 7th day posttransplant. One patient experienced the accelerated rejection, resulting in the resection of the pancreas and kidney grafts because of the failure of conservative therapy. The incidence of the first rejection episodes at 3 months was 47.1% (8/17). Only the kidney was involved in 35.3% (6/17); and both the pancreas and kidney were involved in 11.8% (2/17). All these patients received a high-dose pulse of methylprednisone (0.5 g·d-1) for 3 days. OKT3 (0.5 mg·d-1) was administered for 7-10 days in two patients with both renal and pancreas rejection. All the grafts were successfully rescued. Conclusion Rejection, particularly acute rejection, is the major cause influencing graft function in SPK transplantation. Monitoring renal function and pancreas exocrine secretion, and reasonable application of immunosuppressants play important roles in the diagnosis and treatment of rejection.

  1. Immunoglobulin G4: an odd antibody

    NARCIS (Netherlands)

    R.C. Aalberse; S.O. Stapel; J. Schuurman; T. Rispens

    2009-01-01

    Despite its well-known association with IgE-mediated allergy, IgG4 antibodies still have several poorly understood characteristics. IgG4 is a very dynamic antibody: the antibody is involved in a continuous process of half-molecules (i.e. a heavy and attached light-chain) exchange. This process, also

  2. Cytotoxic activity against human neuroblastoma and melanoma cells mediated by IgM antibodies derived from peripheral blood of healthy donors.

    Science.gov (United States)

    Devarapu, Satish Kumar; Mamidi, Srinivas; Plöger, Frank; Dill, Othmar; Blixt, Ola; Kirschfink, Michael; Schwartz-Albiez, Reinhard

    2016-06-15

    A small percentage of healthy donors identified in the Western population carry antibodies in their peripheral blood which convey cytotoxic activity against certain human melanoma and neuroblastoma cell lines. We measured the cytotoxic activity of sera and plasmas from healthy donors on the human neuroblastoma cell line Kelly and various melanoma cell lines. Antibodies of IgM isotype, presumably belonging to the class of naturally occurring antibodies, exerted cytotoxic activity in a complement-dependent fashion. Apart from complement-dependent tumor cell lysis, we observed C3 opsonization in all tumor cell lines upon treatment with cytotoxic plasmas. Cell lines tested primarily expressed membrane complement regulatory proteins (mCRP) CD46, CD55 and CD59 to various extents. Blocking of mCRPs by monoclonal antibodies enhanced cell lysis and opsonization, though some melanoma cells remained resistant to complement attack. Epitopes recognized by cytotoxic antibodies were represented by gangliosides such as GD2 and GD3, as evidenced by cellular sialidase pretreatment and enhanced expression of distinct gangliosides. It remains to be clarified why only a small fraction of healthy persons carry these antitumor cytotoxic antibodies.

  3. Cytotoxic activity against human neuroblastoma and melanoma cells mediated by IgM antibodies derived from peripheral blood of healthy donors.

    Science.gov (United States)

    Devarapu, Satish Kumar; Mamidi, Srinivas; Plöger, Frank; Dill, Othmar; Blixt, Ola; Kirschfink, Michael; Schwartz-Albiez, Reinhard

    2016-06-15

    A small percentage of healthy donors identified in the Western population carry antibodies in their peripheral blood which convey cytotoxic activity against certain human melanoma and neuroblastoma cell lines. We measured the cytotoxic activity of sera and plasmas from healthy donors on the human neuroblastoma cell line Kelly and various melanoma cell lines. Antibodies of IgM isotype, presumably belonging to the class of naturally occurring antibodies, exerted cytotoxic activity in a complement-dependent fashion. Apart from complement-dependent tumor cell lysis, we observed C3 opsonization in all tumor cell lines upon treatment with cytotoxic plasmas. Cell lines tested primarily expressed membrane complement regulatory proteins (mCRP) CD46, CD55 and CD59 to various extents. Blocking of mCRPs by monoclonal antibodies enhanced cell lysis and opsonization, though some melanoma cells remained resistant to complement attack. Epitopes recognized by cytotoxic antibodies were represented by gangliosides such as GD2 and GD3, as evidenced by cellular sialidase pretreatment and enhanced expression of distinct gangliosides. It remains to be clarified why only a small fraction of healthy persons carry these antitumor cytotoxic antibodies. PMID:26830059

  4. Rhoh deficiency reduces peripheral T-cell function and attenuates allogenic transplant rejection

    DEFF Research Database (Denmark)

    Porubsky, Stefan; Wang, Shijun; Kiss, Eva;

    2011-01-01

    better graft function. This effect was independent of the lower T-cell numbers in Rhoh-deficient recipients, because injection of equal numbers of Rhoh-deficient or control T cells into kidney transplanted mice with SCID led again to a significant 60% reduction of rejection. Mixed lymphocyte reaction...... deficiency in a clinically relevant situation, in which T-cell inhibition is desirable. In murine allogenic kidney transplantation, Rhoh deficiency caused a significant 75% reduction of acute and chronic transplant rejection accompanied by 75% lower alloantigen-specific antibody levels and significantly...

  5. Rejection of pharmaceuticals by forward osmosis membranes.

    Science.gov (United States)

    Jin, Xue; Shan, Junhong; Wang, Can; Wei, Jing; Tang, Chuyang Y

    2012-08-15

    Rejection of four pharmaceutical compounds, carbamazepine, diclofenac, ibuprofen and naproxen, by forward osmosis (FO) membranes was investigated in this study. For the first time, the rejection efficiency of the pharmaceutical compounds was compared between commercial cellulose triacetate (CTA) based membranes and thin film composite (TFC) polyamide based membranes. The rejection behavior was related to membrane interfacial properties, physicochemical characteristics of the pharmaceutical molecules and feed solution pH. TFC polyamide membranes exhibited excellent overall performance, with high water flux, excellent pH stability and great rejection of all pharmaceuticals investigated (>94%). For commercial CTA based FO membranes, hydrophobic interaction between the compounds and membranes exhibited strong influence on their rejection under acidic conditions. The pharmaceuticals rejection was well correlated to their hydrophobicity (log D). Under alkaline conditions, both electrostatic repulsion and size exclusion contributed to the removal of deprotonated molecules. The pharmaceuticals rejection by CTA-HW membrane at pH 8 followed the order: diclofenac (99%)>carbamazepine (95%)>ibuprofen (93%) ≈ naproxen (93%). These results can be important for FO membrane synthesis, modification and their application in water purification. PMID:22640821

  6. Pericytes, microvasular dysfunction, and chronic rejection.

    Science.gov (United States)

    Kloc, Malgorzata; Kubiak, Jacek Z; Li, Xian C; Ghobrial, Rafik M

    2015-04-01

    Chronic rejection of transplanted organs remains the main obstacle in the long-term success of organ transplantation. Thus, there is a persistent quest for development of antichronic rejection therapies and identification of novel molecular and cellular targets. One of the potential targets is the pericytes, the mural cells of microvessels, which regulate microvascular permeability, development, and maturation by controlling endothelial cell functions and regulating tissue fibrosis and inflammatory response. In this review, we discuss the potential of targeting pericytes in the development of microvasular dysfunction and the molecular pathways involved in regulation of pericyte activities for antichronic rejection intervention.

  7. Anti-GaL IgG antibodies in sera of newborn humans and baboons and its significance in pig xenotransplantation.

    Science.gov (United States)

    Minanov, O P; Itescu, S; Neethling, F A; Morgenthau, A S; Kwiatkowski, P; Cooper, D K; Michler, R E

    1997-01-27

    We have previously demonstrated that hyperacute rejection does not occur in a pig-to-newborn baboon heart transplant model, presumably because of low levels of cytotoxic antipig antibodies present in the serum of newborn baboons. Cytotoxic antipig antibodies are primarily directed to alpha-1,3-galactosyl (alpha Gal) residues on endothelial cell surface structures Twenty-one full-term humans and 5 full-term baboons were tested for complement mediated lysis (CML) of pig kidney (PK-15) cells and anti-alpha Gal activity with an ELISA using BSA-conjugated alpha Gal residues as target. To evaluate the significance of the anti-alpha Gal titers in vivo 5 newborn baboons underwent heterotopic pig cardiac xenotransplantation. Six of 21 human samples and 1 of 5 baboon samples demonstrated significant cytotoxicity to PK-15 cells. Twelve of 21 newborn humans had anti-alpha Gal IgG antibodies at titers of 1:80 or greater. None of the samples had anti-alpha Gal IgM. In newborn baboons, 1 of 5 sera had anti-alpha Gal IgG antibodies at titers greater than 1:80 and none of these samples had anti-alpha Gal IgM. Xenografts survived for an average of 3.6 days, even in the baboon with high anti-alpha Gal IgG titers. Analysis of the explanted grafts showed minimal evidence of complement-mediated hyperacute rejection (HAR), but prominent mononuclear cell infiltrates. In serum tested posttransplant there was an induced anti-alpha Gal response with cytotoxicity against PK-15 cells. These results show that anti-alpha Gal IgM is absent in newborn human and baboon sera, allowing pig grafts to avoid HAR. However, the presence of anti-alpha Gal IgG may be associated with mononuclear cell infiltration of the xenograft and its subsequent rejection. PMID:9020315

  8. Role of interferon-γ and cytotoxic T lymphocytes in intraocular tumor rejection.

    Science.gov (United States)

    Ligocki, Ann J; Brown, Joseph R; Niederkorn, Jerry Y

    2016-05-01

    The eye is normally an immunosuppressive environment. This condition is better known as immune privilege and protects the eye from immune-mediated inflammation of tissues that cannot regenerate. However, immune privilege creates a dilemma for the eye when intraocular neoplasms arise. In some cases, immune privilege is suspended, resulting in the immune rejection of intraocular tumors. This study employed a mouse model in which interferon-γ-dependent intraocular tumor rejection occurs. We tested the hypothesis that this rejection requires interferon-γ for the generation and functional capacity of cytotoxic T lymphocyte-mediated rejection of intraocular tumors. Tumors grew progressively in the eyes of interferon-γ knockout mice, even though the mice generated tumor-specific cytotoxic T lymphocyte responses in the periphery. However, interferon-γ knockout mice rejected tumors that were introduced into extraocular sites. Subcutaneous tumor immunization before intraocular challenge led to tumor rejection and preservation of the eye in wild-type mice. By contrast, tumors grew progressively in the eyes of interferon-γ knockout mice despite their ability to generate peripheral tumor-specific cytotoxic T lymphocytes as well as the capacity of CD8(+) T cells to enter the eye as shown by the presence of CD8 and perforin message and CD3(+)CD8(+) leukocytes within the tumor-bearing eye. We found that cytotoxic T lymphocytes generated in wild-type mice and adoptively transferred into interferon-γ knockout mice mediated the rejection of intraocular tumors in interferon-γ knockout hosts. The results indicate that interferon-γ is critical for the initial priming and differentiation of cytotoxic T lymphocytes residing in the periphery to produce the most effect antitumor function within the eye.

  9. Friendship quantity and quality as predictors of rejection sensitivity in adolescents

    Directory of Open Access Journals (Sweden)

    Gabriela Šeboková

    2014-12-01

    (greater or lesser contributions to rejection sensitivity. Different types of peer relations can moderate and mediate each other´s influence on specific types of internalizing problems in adolescents. The future research simultaneously examining more types of peer relationship is needed. There has been empirical evidence that girls have more quality friendships which provide them more emotional and instrumental support, than for boys. Our results support this empirical evidence. Regression analysis indicated, that balance (large effect size, help, security and closeness in friendship (small to medium effect size and overall friendship quality (medium effect size are significant unique predictors of rejection sensitivity for adolescent girls, but not for boys. Results suggest that predictors of sensitivity rejection in boys are other than interpersonal factors, for example personal or coping strategies. Further directions in research are discussed.

  10. Targeting Tumor Cells with Anti-CD44 Antibody Triggers Macrophage-Mediated Immune Modulatory Effects in a Cancer Xenograft Model.

    Science.gov (United States)

    Maisel, Daniela; Birzele, Fabian; Voss, Edgar; Nopora, Adam; Bader, Sabine; Friess, Thomas; Goller, Bernhard; Laifenfeld, Daphna; Weigand, Stefan; Runza, Valeria

    2016-01-01

    CD44, a transmembrane receptor reported to be involved in various cellular functions, is overexpressed in several cancer types and supposed to be involved in the initiation, progression and prognosis of these cancers. Since the sequence of events following the blockage of the CD44-HA interaction has not yet been studied in detail, we profiled xenograft tumors by RNA Sequencing to elucidate the mode of action of the anti-CD44 antibody RG7356. Analysis of tumor and host gene-expression profiles led us to the hypothesis that treatment with RG7356 antibody leads to an activation of the immune system. Using cytokine measurements we further show that this activation involves the secretion of chemo-attractants necessary for the recruitment of immune cells (i.e. macrophages) to the tumor site. We finally provide evidence for antibody-dependent cellular phagocytosis (ADCP) of the malignant cells by macrophages. PMID:27463372

  11. Targeting Tumor Cells with Anti-CD44 Antibody Triggers Macrophage-Mediated Immune Modulatory Effects in a Cancer Xenograft Model.

    Directory of Open Access Journals (Sweden)

    Daniela Maisel

    Full Text Available CD44, a transmembrane receptor reported to be involved in various cellular functions, is overexpressed in several cancer types and supposed to be involved in the initiation, progression and prognosis of these cancers. Since the sequence of events following the blockage of the CD44-HA interaction has not yet been studied in detail, we profiled xenograft tumors by RNA Sequencing to elucidate the mode of action of the anti-CD44 antibody RG7356. Analysis of tumor and host gene-expression profiles led us to the hypothesis that treatment with RG7356 antibody leads to an activation of the immune system. Using cytokine measurements we further show that this activation involves the secretion of chemo-attractants necessary for the recruitment of immune cells (i.e. macrophages to the tumor site. We finally provide evidence for antibody-dependent cellular phagocytosis (ADCP of the malignant cells by macrophages.

  12. Comparison of the C-mediating killing activity and C-activating properties of mouse monoclonal and polyclonal antibodies against Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    T. L. Kipnis

    1992-01-01

    Full Text Available A Mouse polyclonal antiserum against Trypanosoma cruzi or its IgG and IgM fractions and five monoclonal antibodies (two IgM, two IgG1 and one IgG2a recognize and combine with membrane components of trypomastigote forms of the parasite as revealed by immunofluorescence. Although all these antibodies sensitize trypomastigotes and prepare them to activate the complement (C system, as measured by consumption of total C, C4, B and C3, only the polyclonal antiserum or its IgG, IgM and Fabμ fragments were able to induce trypanosome lysis by the alternative C pathway.

  13. Occurrence of Fatal and Nonfatal Adverse Outcomes after Heart Transplantation in Patients with Pretransplant Noncytotoxic HLA Antibodies

    Directory of Open Access Journals (Sweden)

    Luciano Potena

    2013-01-01

    Full Text Available HLA antibodies (HLA ab in transplant candidates have been associated with poor outcome. However, clinical relevance of noncytotoxic antibodies after heart transplant (HT is controversial. By using a Luminex-based HLA screening, we retested pretransplant sera from HT recipients testing negative for cytotoxic HLA ab and for prospective crossmatch. Out of the 173 consecutive patients assayed (52±13y; 16% females; 47% ischemic etiology, 32 (18% showed pretransplant HLA ab, and 12 (7% tested positive against both class I and class II HLA. Recipients with any HLA ab had poorer survival than those without (65±9 versus 82±3%; P=0.02, accounting for a doubled independent mortality risk (P=0.04. In addition, HLA-ab detection was associated with increased prevalence of early graft failure (35 versus 15%; P=0.05 and late cellular rejection (29 versus 11%; P=0.03. Of the subgroup of 37 patients suspected for antibody mediated rejection (AMR, the 9 with pretransplant HLA ab were more likely to display pathological AMR grade 2 (P=0.04. By an inexpensive, luminex-based, HLA-screening assay, we were able to detect non-cytotoxic HLA ab predicting fatal and nonfatal adverse outcomes after heart transplant. Allocation strategies and desensitization protocols need to be developed and prospectively tested in these patients.

  14. Structural Decoupling and Disturbance Rejection in a Distillation Column

    DEFF Research Database (Denmark)

    Bahar, Mehrdad; Jantzen, Jan; Commault, C.;

    1996-01-01

    Introduction, distillation column model, input-output decoupling, disturbance rejection, concluding remarks, references.......Introduction, distillation column model, input-output decoupling, disturbance rejection, concluding remarks, references....

  15. Bovine Colostrum Contains Immunoglobulin G Antibodies against Intimin, EspA, and EspB and Inhibits Hemolytic Activity Mediated by the Type Three Secretion System of Attaching and Effacing Escherichia coli▿

    Science.gov (United States)

    Vilte, Daniel A.; Larzábal, Mariano; Cataldi, Ángel A.; Mercado, Elsa C.

    2008-01-01

    Enterohemorrhagic Escherichia coli (EHEC) is the main cause of hemolytic-uremic syndrome, an endemic disease in Argentina which had an incidence in 2005 of 13.9 cases per 100,000 children younger than 5 years old. Cattle appear to be a major reservoir of EHEC, and a serological response to EHEC antigens has been demonstrated in natural and experimental infections. In the current study, antibodies against proteins implicated in EHEC's ability to form attaching and effacing lesions, some of which are exported to the host cell via a type three secretion system (TTSS), were identified in bovine colostrum by Western blot analysis. Twenty-seven (77.0%) of the 35 samples examined contained immunoglobulin G (IgG) antibodies against the three proteins assayed in this study: EspA, EspB, and the carboxy-terminal 280 amino acids of γ-intimin, an intimin subtype associated mainly with O157:H7 and O145:H- serotypes. Every colostrum sample was able to inhibit, in a range between 45.9 and 96.7%, the TTSS-mediated hemolytic activity of attaching and effacing E. coli. The inhibitory effect was partially mediated by IgG and lactoferrin. In conclusion, we found that early colostrum from cows contains antibodies, lactoferrin, and other unidentified substances that impair TTSS function in attaching and effacing E. coli strains. Bovine colostrum might act by reducing EHEC colonization in newborn calves and could be used as a prophylactic measure to protect non-breast-fed children against EHEC infection in an area of endemicity. PMID:18562563

  16. Corneal Graft Rejection: Incidence and Risk Factors

    Directory of Open Access Journals (Sweden)

    Alireza Baradaran-Rafii

    2008-12-01

    Full Text Available

    PURPOSE: To determine the incidence and risk factors of late corneal graft rejection after penetrating keratoplasty (PKP. METHODS: Records of all patients who had undergone PKP from 2002 to 2004 without immunosuppressive therapy other than systemic steroids and with at least one year of follow up were reviewed. The role of possible risk factors such as demographic factors, other host factors, donor factors, indications for PKP as well as type of rejection were evaluated. RESULTS: During the study period, 295 PKPs were performed on 286 patients (176 male, 110 female. Mean age at the time of keratoplasty was 38±20 (range, 40 days to 90 years and mean follow up period was 20±10 (range 12-43 months. Graft rejection occurred in 94 eyes (31.8% at an average of 7.3±6 months (range, 20 days to 39 months after PKP. The most common type of rejection was endothelial (20.7%. Corneal vascularization, regrafting, anterior synechiae, irritating sutures, active inflammation, additional anterior segment procedures, history of trauma, uncontrolled glaucoma, prior graft rejection, recurrence of herpetic infection and eccentric grafting increased the rate of rejection. Patient age, donor size and bilateral transplantation had no significant influence on graft rejection. CONCLUSION: Significant risk factors for corneal graft rejection include

  17. Image rejects in general direct digital radiography

    International Nuclear Information System (INIS)

    The number of rejected images is an indicator of image quality and unnecessary imaging at a radiology department. Image reject analysis was frequent in the film era, but comparably few and small studies have been published after converting to digital radiography. One reason may be a belief that rejects have been eliminated with digitalization. To measure the extension of deleted images in direct digital radiography (DR), in order to assess the rates of rejects and unnecessary imaging and to analyze reasons for deletions, in order to improve the radiological services. All exposed images at two direct digital laboratories at a hospital in Norway were reviewed in January 2014. Type of examination, number of exposed images, and number of deleted images were registered. Each deleted image was analyzed separately and the reason for deleting the image was recorded. Out of 5417 exposed images, 596 were deleted, giving a deletion rate of 11%. A total of 51.3% were deleted due to positioning errors and 31.0% due to error in centering. The examinations with the highest percentage of deleted images were the knee, hip, and ankle, 20.6%, 18.5%, and 13.8% respectively. The reject rate is at least as high as the deletion rate and is comparable with previous film-based imaging systems. The reasons for rejection are quite different in digital systems. This falsifies the hypothesis that digitalization would eliminates rejects. A deleted image does not contribute to diagnostics, and therefore is an unnecessary image. Hence, the high rates of deleted images have implications for management, training, education, as well as for quality

  18. Tracing the antibody mediated acquired immunity by Foot and Mouth disease and Rift Valley Fever combined vaccine in pregnant ewes and their lambs

    Directory of Open Access Journals (Sweden)

    Wael Mossad Gamal

    2014-11-01

    Full Text Available Aim: The aim of this study was to provide adequate protection to ewes and their lambs against Foot and Mouth disease (FMD and Rift Valley Fever (RVF. Materials and Methods: A combined inactivated oil vaccine was prepared successfully. Such vaccine was found to be free from foreign contaminants, safe and potent as determined by quality control tests such as challenge protection percentage for FMD and mice ED50 for RVF. Vaccination of pregnant ewes with the prepared combined vaccine and determination of the antibody level via serum neutralization test (SNT and Enzyme Linked immune sorbent assay (ELISA in the vaccinated pregnant ewes and their lambs. Results: Vaccination of pregnant ewes revealed that these ewes exhibited high levels of specific antibodies against the included vaccine antigens (Foot and Mouth disease virus type A Iran O5, O PanAsia and SAT2/EGY/2012 and RVFV-ZH501. FMD antibodies recorded their peaks by the 10th week while those of RVF recorded their peaks by the 12th week post vaccination then all antibodies began to decrease gradually to reach their lowest protective titers for FMD by the 32nd week post vaccination and those for RVF by the 34th week post vaccination. Potency test of the prepared combined vaccine expressed as protection percentage of vaccinated sheep against target virulent FMD virus serotypes reflected a protection percentage of 80% against type O and SAT2 and 100% against A while for RVF, the mice ED50 was found to be 0.009 indicating the potency of the prepared vaccine. The antibody titer in serum and colostrum of vaccinated pregnant ewes at day of parturition (10-12 week post vaccination recorded a high titer against FMD serotype (O, serotype (A, serotype (SAT2 and against RVF. It was noticed that the colostrum antibody titers were slightly higher than those in the sera of vaccinated ewes at time of parturition. The newly born lambs from vaccinated ewes, exhibited good levels of maternal immunity against the

  19. Hyperlipidemia Promotes Anti-Donor Th17 Responses That Accelerate Allograft Rejection.

    Science.gov (United States)

    Yuan, J; Bagley, J; Iacomini, J

    2015-09-01

    Hyperlipidemia occurs in 95% of organ transplant recipients, however its effect on organ allograft rejection has not been investigated. We found that induction of hyperlipidemia in mice caused a significant acceleration of rejection of cardiac allografts. Accelerated rejection was associated with an aggressive T cell infiltrate that mediated significant tissue damage as well as increased serum levels of the proinflammatory cytokines IL-2, IL-6, and IL-17. Hyperlipidemic mice had an increased number of Th17 cells in their periphery and rejecting allografts from hyperlipidemic mice contained significant numbers of IL-17 producing T cells that were not detectable in transplants harvested from controls. Neutralization or genetic ablation of IL-17 prolonged survival of cardiac allografts transplanted into hyperlipidemic recipients, suggesting that IL-17 production promotes accelerated rejection. Analysis of alloreactive T cell frequencies directly ex vivo in naïve mice revealed that the frequency of donor reactive IL-17 producing cells in hyperlipidemic was increased prior to antigen exposure, suggesting that hyperlipidemia was sufficient to alter T cell alloreactivity and promote anti-donor Th17 responses on first exposure to antigen. Together, our data suggest that hyperlipidemia alters rejection by altering the types of T cell subsets that respond to donor antigen by promoting Th17 biased anti-donor reactivity.

  20. Simple and Efficient Method for Measuring Anti-Toxoplasma Immunoglobulin Antibodies in Human Sera Using Complement-Mediated Lysis of Transgenic Tachyzoites Expressing β-Galactosidase

    Science.gov (United States)

    Dando, Caroline; Gabriel, Katie E.; Remington, Jack S.; Parmley, Stephen F.

    2001-01-01

    A simple and efficient method using transgenic Toxoplasma gondii tachyzoites expressing β-galactosidase was developed for detection of specific antibodies against the parasite in sera of patients. The titers obtained with the new test were similar to those obtained with the Sabin-Feldman dye test run in parallel. Although significant changes in endpoint titers were not observed when sera drawn sequentially at 2- to 3-week intervals were tested with both procedures, apparent differences in antibody affinity were observed with the new test which were not perceptible with the Sabin-Feldman dye test. Like the Sabin-Feldman dye test, the new test is based on complement lysis of tachyzoites, but it is much easier to perform and the reaction is read colorimetrically instead of visually. PMID:11376045

  1. The influence of the swine major histocompatibility genes on antibody and cell-mediated immune responses to immunization with an aromatic-dependent mutant of Salmonella typhimurium.

    OpenAIRE

    Lumsden, J S; Kennedy, B. W.; Mallard, B A; Wilkie, B. N.

    1993-01-01

    Eighty-two major histocompatibility complex (MHC) swine leukocyte antigen (SLA) defined miniature pigs from 16 litters were examined for serum agglutinating antibody titer and O-polysaccharide (O-ps) specific peripheral blood lymphocyte blastogenesis following two parenteral vaccinations with 1 x 10(8) aromatic-dependent (aroA) Salmonella typhimurium and following oral challenge with 1 x 10(12) virulent parent S. typhimurium. Least mean squares analysis allowed separate determinations of the ...

  2. Mouse kidney transplantation: models of allograft rejection.

    Science.gov (United States)

    Tse, George H; Hesketh, Emily E; Clay, Michael; Borthwick, Gary; Hughes, Jeremy; Marson, Lorna P

    2014-01-01

    Rejection of the transplanted kidney in humans is still a major cause of morbidity and mortality. The mouse model of renal transplantation closely replicates both the technical and pathological processes that occur in human renal transplantation. Although mouse models of allogeneic rejection in organs other than the kidney exist, and are more technically feasible, there is evidence that different organs elicit disparate rejection modes and dynamics, for instance the time course of rejection in cardiac and renal allograft differs significantly in certain strain combinations. This model is an attractive tool for many reasons despite its technical challenges. As inbred mouse strain haplotypes are well characterized it is possible to choose donor and recipient combinations to model acute allograft rejection by transplanting across MHC class I and II loci. Conversely by transplanting between strains with similar haplotypes a chronic process can be elicited were the allograft kidney develops interstitial fibrosis and tubular atrophy. We have modified the surgical technique to reduce operating time and improve ease of surgery, however a learning curve still needs to be overcome in order to faithfully replicate the model. This study will provide key points in the surgical procedure and aid the process of establishing this technique.

  3. The influence of the swine major histocompatibility genes on antibody and cell-mediated immune responses to immunization with an aromatic-dependent mutant of Salmonella typhimurium.

    Science.gov (United States)

    Lumsden, J S; Kennedy, B W; Mallard, B A; Wilkie, B N

    1993-01-01

    Eighty-two major histocompatibility complex (MHC) swine leukocyte antigen (SLA) defined miniature pigs from 16 litters were examined for serum agglutinating antibody titer and O-polysaccharide (O-ps) specific peripheral blood lymphocyte blastogenesis following two parenteral vaccinations with 1 x 10(8) aromatic-dependent (aroA) Salmonella typhimurium and following oral challenge with 1 x 10(12) virulent parent S. typhimurium. Least mean squares analysis allowed separate determinations of the effects of MHC genotype, dam, sire and litter. In most cases only litter significantly influenced both lymphocyte blastogenesis and antibody titer before and after vaccination and following challenge. However, pig SLA haplotype significantly influenced the degree of O-ps specific lymphocyte proliferation six days after the second vaccination (p < 0.004). Lymphocyte proliferation and serum agglutinating antibody response six days after primary vaccination were negatively correlated (r2 = -0.68, p < 0.001). In most cases, "dd" and "gg" homozygous and "dg" heterozygous pigs, having the same MHC class II region, behaved immunologically as a group distinct from the other genotypes. PMID:8431799

  4. Effect of yeast-derived products and distillers dried grains with solubles (DDGS) on antibody-mediated immune response and gene expression of pattern recognition receptors and cytokines in broiler chickens immunized with T-cell dependent antigens.

    Science.gov (United States)

    Alizadeh, M; Rodriguez-Lecompte, J C; Echeverry, H; Crow, G H; Slominski, B A

    2016-04-01

    This study evaluated the effect of yeast-derived products on innate and antibody mediated immune response in broiler chickens following immunization with sheep red blood cells (SRBC) and bovine serum albumin (BSA). One-day-old male broiler chickens (Ross-308) were randomly assigned to 6 dietary treatments of 9 replicate cages of 5 birds each per treatment. Dietary treatments consisted of a Control diet without antibiotic, and diets containing 11 mg/kg of virginiamycin, 0.25% of yeast cell wall (YCW), 0.2% of a commercial product Maxi-Gen Plus containing processed yeast and nucleotides, 0.05% of nucleotides, or a diet containing 10% of DDGS. On days 21 and 28 post-hatching, 5 birds per treatment were immunized intramuscularly with both SRBC and BSA. One week after each immunization, blood samples were collected. Serum samples were analyzed by hemagglutination test for antibody response to SRBC, and by ELISA for serum IgM and IgG response to BSA. On d 35, 5 birds per treatment were euthanized and the tissue samples from the cecal tonsils were collected to assess the gene expression of toll-like receptors TLR2b, TLR4, and TLR21, monocyte mannose receptor (MMR), and cytokines IL-10, IL-13, IL-4, IL-12p35, and IFN-γ. The results for gene expression analysis demonstrated that the diet supplemented with YCW increased the expression of TLR2b and T-helper type 2 cytokines IL-10, IL-4, and IL-13 relative to the Control; and the expression of TLR4 and IL-13 was upregulated in the nucleotide-containing diet. However, the diets containing antibiotics or Maxi-Gen Plus downregulated the expression of IFN-γ compared to the control. The primary antibody response to SRBC was not affected by diets. However, the diet containing YCW increased the secondary antibody response to SRBC compared to the antibiotic treatment. Neither primary nor secondary IgG and IgM response against BSA were affected by diets. In conclusion, supplementation of the diet with YCW stimulated Th2 cell-mediated

  5. Rejection of pharmaceuticals by nanofiltration (NF) membranes: Effect of fouling on rejection behaviour

    Science.gov (United States)

    Mahlangu, T. O.; Msagati, T. A. M.; Hoek, E. M. V.; Verliefde, A. R. D.; Mamba, B. B.

    The aim of this study was to investigate the effects of membrane fouling by sodium alginate, latex and a combination of alginate + latex on the rejection behaviour of salts and organics. Sodium chloride and caffeine were selected to represent salts and organics, respectively. The effects of the presence of calcium chloride on the fouling behaviour and rejection of solutes were investigated. The results revealed that the salt rejection by virgin membranes was 47% while that of caffeine was 85%. Fouling by alginate, latex and combined alginate-latex resulted in flux decline of 25%, 37% and 17%, respectively. The addition of Ca2+ aggravated fouling and resulted in further flux decline to 37%. Fouling decreased salt rejection, an observation that was further aggravated by the addition on Ca2+. However, it was also observed that fouling with alginate and calcium and with latex and calcium minimised salt rejection by 30% and 31%, respectively. This reduction in salt rejection was attributed to the decrease in permeate flux (since rejection is a function of flux). There was a slight increase in caffeine rejection when the membrane was fouled with latex particles. Moreover, the presence of foulants on the membrane resulted in a decrease in the surface charge of the membrane. The results of this study have shown that the NF 270 membrane can be used to treat water samples contaminated with caffeine and other organic compounds that have physicochemical properties similar to those of caffeine.

  6. Amyloid-β oligomer specificity mediated by the IgM isotype--implications for a specific protective mechanism exerted by endogenous auto-antibodies.

    Directory of Open Access Journals (Sweden)

    Malin Lindhagen-Persson

    Full Text Available BACKGROUND: Alzheimers disease (AD has been strongly linked to an anomalous self-assembly of the amyloid-β peptide (Aβ. The correlation between clinical symptoms of AD and Aβ depositions is, however, weak. Instead small and soluble Aβ oligomers are suggested to exert the major pathological effects. In strong support of this notion, immunological targeting of Aβ oligomers in AD mice-models shows that memory impairments can be restored without affecting the total burden of Aβ deposits. Consequently a specific immunological targeting of Aβ oligomers is of high therapeutic interest. METHODOLOGY/PRINCIPAL FINDINGS: Previously the generation of conformational-dependent oligomer specific anti-Aβ antibodies has been described. However, to avoid the difficult task of identifying a molecular architecture only present on oligomers, we have focused on a more general approach based on the hypothesis that all oligomers expose multiple identical epitopes and therefore would have an increased binding to a multivalent receptor. Using the polyvalent IgM immunoglobulin we have developed a monoclonal anti-Aβ antibody (OMAB. OMAB only demonstrates a weak interaction with Aβ monomers and dimers having fast on and off-rate kinetics. However, as an effect of avidity, its interaction with Aβ-oligomers results in a strong complex with an exceptionally slow off-rate. Through this mechanism a selectivity towards Aβ oligomers is acquired and OMAB fully inhibits the cytotoxic effect exerted by Aβ(1-42 at highly substoichiometric ratios. Anti-Aβ auto-antibodies of IgM isotype are frequently present in the sera of humans. Through a screen of endogenous anti-Aβ IgM auto-antibodies from a group of healthy individuals we show that all displays a preference for oligomeric Aβ. CONCLUSIONS/SIGNIFICANCE: Taken together we provide a simple and general mechanism for targeting of oligomers without the requirement of conformational-dependent epitopes. In addition, our

  7. In-vitro inhibition of IFNγ+ iTreg mediated by monoclonal antibodies against cell surface determinants essential for iTreg function

    Directory of Open Access Journals (Sweden)

    Daniel Volker

    2012-08-01

    Full Text Available Abstract Background IFNγ-producing CD4+CD25+Foxp3+ PBL represent a subtype of iTreg that are associated with good long-term graft outcome in renal transplant recipients and suppress alloresponses in-vitro. To study the mechanism of immunosuppression, we attempted to block cell surface receptors and thereby inhibited the function of this iTreg subset in-vitro using monoclonal antibodies and recombinant proteins. Methods PBL of healthy control individuals were stimulated polyclonally in-vitro in the presence of monoclonal antibodies or recombinant proteins against/of CD178, CD152, CD279, CD28, CD95, and HLA-DR. Induction of IFNγ+ iTreg and proliferation of effector cells was determined using four-color fluorescence flow cytometry. Blockade of iTreg function was analyzed using polyclonally stimulated co-cultures with separated CD4+CD25+CD127-IFNγ+ PBL. Results High monoclonal antibody concentrations inhibited the induction of CD4+CD25+Foxp3+IFNγ+ PBL (anti-CD152, anti-CD279, anti-CD95: p +CD25+CD127-IFNγ+ PBL (anti-CD178, anti-CD152, anti-CD279, anti-CD95: p +CD25+Foxp3+IFNγ+ PBL (rCD152 and rCD95: p +CD25+CD127-IFNγ+ PBL showed lower cell proliferation than co-cultures with CD4+CD25+CD127-IFNγ- PBL (p +CD25+CD127-IFNγ- PBL-containing co-cultures in the presence of monoclonal antibody (anti-CD28, anti-CD152, anti-CD279: p +CD25+CD127-IFNγ+ PBL (with the exception anti-CD28 monoclonal antibody: p +CD25+CD127-IFNγ- PBL but do not efficiently block suppressive iTreg function in co-cultures with CD4+CD25+CD127-IFNγ+ PBL. Conclusions CD178, CD152, CD279, CD28, CD95, and HLA-DR determinants are important for induction and suppressive function of IFNγ+ iTreg.

  8. Preventing Allograft Rejection by Targeting Immune Metabolism

    Directory of Open Access Journals (Sweden)

    Chen-Fang Lee

    2015-10-01

    Full Text Available Upon antigen recognition and co-stimulation, T lymphocytes upregulate the metabolic machinery necessary to proliferate and sustain effector function. This metabolic reprogramming in T cells regulates T cell activation and differentiation but is not just a consequence of antigen recognition. Although such metabolic reprogramming promotes the differentiation and function of T effector cells, the differentiation of regulatory T cells employs different metabolic reprogramming. Therefore, we hypothesized that inhibition of glycolysis and glutamine metabolism might prevent graft rejection by inhibiting effector generation and function and promoting regulatory T cell generation. We devised an anti-rejection regimen involving the glycolytic inhibitor 2-deoxyglucose (2-DG, the anti-type II diabetes drug metformin, and the inhibitor of glutamine metabolism 6-diazo-5-oxo-L-norleucine (DON. Using this triple-drug regimen, we were able to prevent or delay graft rejection in fully mismatched skin and heart allograft transplantation models.

  9. Video auditing techniques for breaker reject

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, B.M.; Corke, P.I.; O`Brien, G.D.; Waugh, J.M. [CSIRO (Australia). Division of Minerals

    1998-12-31

    Rotary breakers are used by many Australian coal mines to reduce the topsize of run of mine (ROM) coal to a size that can be handled by the processing plant. Coal that does not break to the designated topsize therefore passes out with the rock as breaker rejects. The degree of coal loss can be assessed manually by stop belt auditing of the reject belt, but this method is impractical for long-term monitoring of breaker rejects and breaker performance. Case studies of several open cut coal mines in the Bowen Basin of Central Queensland were made to determine the extent of the problem. The results indicated instances where significant losses did occur, but it was not possible to make an accurate estimate of the total value of the losses. This paper covers work undertaken to develop new auditing techniques for qualitative, quantitative and continuous monitoring of reject belt material which uses relatively low-cost equipment and mature technology. Initial work has concentrated on developing video surveillance techniques suitable for the range of environmental conditions typically encountered in the field. Multi-media methods are being developed for qualitative data presentation, and image analysis techniques are being investigated to extract basic quantitative information from video sequences, such as particle size and shape. Future work includes development of automatic methods using machine vision for 100% on-line inspection. The main attraction of the methodology being adopted is the potential to easily adapt the techniques to diagnostic and control functions. In situations where significant losses occur, this approach could open up many possibilities for reducing coal rejection or allowing its recovery from the rejects stream to improve productivity. 12 refs., 4 figs., 1 tab.

  10. Solar dynamic space power system heat rejection

    Science.gov (United States)

    Carlson, A. W.; Gustafson, E.; Mclallin, K. L.

    1986-01-01

    A radiator system concept is described that meets the heat rejection requirements of the NASA Space Station solar dynamic power modules. The heat pipe radiator is a high-reliability, high-performance approach that is capable of erection in space and is maintainable on orbit. Results are present of trade studies that compare the radiator system area and weight estimates for candidate advanced high performance heat pipes. The results indicate the advantages of the dual-slot heat pipe radiator for high temperature applications as well as its weight-reduction potential over the range of temperatures to be encountered in the solar dynamic heat rejection systems.

  11. Prevention of rejection of allogeneic endothelial cells in a biohybrid lung by silencing HLA-class I expression.

    Science.gov (United States)

    Wiegmann, Bettina; Figueiredo, Constança; Gras, Christiane; Pflaum, Michael; Schmeckebier, Sabrina; Korossis, Sotirios; Haverich, Axel; Blasczyk, Rainer

    2014-09-01

    Variability in Human Leukocyte Antigens (HLA) remains a hurdle to the application of allogeneic cellular products. Due to insufficient autologous endothelial cell harvesting for the biohybrid lung, allogeneic human cord blood derived endothelial cells (HCBEC) were used for the endothelialization of poly-4-methyl-1-pentene (PMP) gas exchange membranes. Therefore, HLA class I expression was silenced stably in HCBECs to prevent rejection. The capacity of HLA class I-silenced HCBEC to abrogate allogeneic immune responses, their functional properties and suitability for endothelialization of PMP membranes were investigated. Delivery of β2-microglobulin (β2m)-specific shRNAs reduced β2m mRNA levels by up to 90% and caused a knockdown of HLA class I expression by up to 85%. HLA-silenced HCBEC abrogated T-cell responses and escaped antibody-mediated complement-dependent cytotoxicity. The EC phenotype and cytokine secretion profiles between HLA-expressing or -silenced HCBEC remained unaltered. EC specific activation (e.g. ICAM) and thrombogenic markers (e.g. thrombomodulin) remained unaffected by HLA-silencing, but their expression was upregulated by TNFα-stimulation. Furthermore, HLA-silenced HCBECs showed high proliferation rates and built an EC monolayer onto PMP membranes. This study represents a new therapeutic concept in the field of cell and organ transplantation and may bring the bioartificial lung as an alternative to lung transplantation closer to reality.

  12. Biochemical and structural characterization of the interface mediating interaction between the influenza A virus non-structural protein-1 and a monoclonal antibody

    Science.gov (United States)

    Wu, Jianping; Mok, Chee-Keng; Chow, Vincent Tak Kwong; Yuan, Y. Adam; Tan, Yee-Joo

    2016-01-01

    We have previously shown that a non-structural protein 1 (NS1)-binding monoclonal antibody, termed as 2H6, can significantly reduce influenza A virus (IAV) replication when expressed intracellularly. In this study, we further showed that 2H6 binds stronger to the NS1 of H5N1 than A/Puerto Rico/8/1934(H1N1) because of an amino acid difference at residue 48. A crystal structure of 2H6 fragment antigen-binding (Fab) has also been solved and docked onto the NS1 structure to reveal the contacts between specific residues at the interface of antibody-antigen complex. In one of the models, the predicted molecular contacts between residues in NS1 and 2H6-Fab correlate well with biochemical results. Taken together, residues N48 and T49 in H5N1 NS1 act cooperatively to maintain a strong interaction with mAb 2H6 by forming hydrogen bonds with residues found in the heavy chain of the antibody. Interestingly, the pandemic H1N1-2009 and the majority of seasonal H3N2 circulating in humans since 1968 has N48 in NS1, suggesting that mAb 2H6 could bind to most of the currently circulating seasonal influenza A virus strains. Consistent with the involvement of residue T49, which is well-conserved, in RNA binding, mAb 2H6 was also found to inhibit the interaction between NS1 and double-stranded RNA. PMID:27633136

  13. Antibody Titer Threshold Predicts Anti-Candidal Vaccine Efficacy Even though the Mechanism of Protection Is Induction of Cell-Mediated Immunity

    OpenAIRE

    Spellberg, Brad; Ibrahim, Ashraf S.; Lin, Lin; Avanesian, Valentina; Fu, Yue; Lipke, Peter; Otoo, Henry; Ho, Tiffany; Edwards, John E.

    2008-01-01

    We previously reported that vaccination with Freund’s adjuvant plus the recombinant N-terminus of the candidal adhesin, Als3p (rAls3p-N), protects mice from disseminated candidiasis. Here we report that the rAls3p-N vaccine is effective when combined with aluminum hydroxide adjuvant. Antibody titers of ≥1:6400 accurately predicted protection from infection. Nevertheless, neither B lymphocytes nor serum from immunized animals transferred protection to vaccine-naive animals. In contrast, CD3+, ...

  14. Myosins 1 and 6, myosin light chain kinase, actin and microtubules cooperate during antibody-mediated internalisation and trafficking of membrane-expressed viral antigens in feline infectious peritonitis virus infected monocytes.

    Science.gov (United States)

    Dewerchin, Hannah L; Desmarets, Lowiese M; Noppe, Ytse; Nauwynck, Hans J

    2014-02-12

    Monocytes infected with feline infectious peritonitis virus, a coronavirus, express viral proteins in their plasma membranes. Upon binding of antibodies, these proteins are quickly internalised through a new clathrin- and caveolae-independent internalisation pathway. By doing so, the infected monocytes can escape antibody-dependent cell lysis. In the present study, we investigated which kinases and cytoskeletal proteins are of importance during internalisation and subsequent intracellular transport. The experiments showed that myosin light chain kinase (MLCK) and myosin 1 are crucial for the initiation of the internalisation. With co-localisation stainings, it was found that MLCK and myosin 1 co-localise with antigens even before internalisation started. Myosin 6 co-localised with the internalising complexes during passage through the cortical actin, were it might play a role in moving or disintegrating actin filaments, to overcome the actin barrier. One minute after internalisation started, vesicles had passed the cortical actin, co-localised with microtubules and association with myosin 6 was lost. The vesicles were further transported over the microtubules and accumulated at the microtubule organising centre after 10 to 30 min. Intracellular trafficking over microtubules was mediated by MLCK, myosin 1 and a small actin tail. Since inhibiting MLCK with ML-7 was so efficient in blocking the internalisation pathway, this target can be used for the development of a new treatment for FIPV.

  15. Antibody induction versus placebo, no induction, or another type of antibody induction for liver transplant recipients

    DEFF Research Database (Denmark)

    Penninga, Luit; Wettergren, André; Wilson, Colin H;

    2014-01-01

    BACKGROUND: Liver transplantation is an established treatment option for end-stage liver failure. To date, no consensus has been reached on the use of immunosuppressive T-cell antibody induction for preventing rejection after liver transplantation. OBJECTIVES: To assess the benefits and harms...... of immunosuppressive T-cell specific antibody induction compared with placebo, no induction, or another type of T-cell specific antibody induction for prevention of acute rejection in liver transplant recipients. SEARCH METHODS: We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane...... Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Science Citation Index Expanded, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) until September 2013. SELECTION CRITERIA: Randomised clinical trials assessing immunosuppression with T...

  16. Computational structural analysis of an anti-l-amino acid antibody and inversion of its stereoselectivity

    OpenAIRE

    Ranieri, Daniel I.; Hofstetter, Heike; Hofstetter, Oliver

    2009-01-01

    The binding site of a monoclonal anti-l-amino acid antibody was modeled using the program SWISS-MODEL. Docking experiments with the enantiomers of phenylalanine revealed that the antibody interacts with l-phenylalanine via hydrogen bonds and hydrophobic contacts, whereas the d-enantiomer is rejected due to steric hindrance. Comparison of the sequences of this antibody and an anti-d-amino acid antibody indicates that both immunoglobulins derived from the same germline progenitor. Substitution ...

  17. Rejection Pathways in Heart Transplant Recipients

    NARCIS (Netherlands)

    N.M. van Besouw (Nicole)

    1999-01-01

    textabstractSince the beginning of this century experimental heart transplantations in animal studies were performed.' These studies were started in Rotterdam in the seventies to compare heterotopic and orthotopic heart transplantations, and to study the process of chronic rejection. The history of

  18. Waste heat rejection from geothermal power stations

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, R.C.

    1978-12-01

    This study of waste heat rejection from geothermal power stations is concerned only with the heat rejected from the power cycle. The heat contained in reinjected or otherwise discharged geothermal fluids is not included with the waste heat considered here. The heat contained in the underflow from the flashtanks in such systems is not considered as part of the heat rejected from the power cycle. By following this definition of the waste heat to be rejected, various methods of waste heat dissipation are discussed without regard for the particular arrangement to obtain heat from the geothermal source. Recent conceptual design studies made for 50-MW(e) geothermal power stations at Heber and Niland, California, are of particular interst. The former uses a flashed-steam system and the latter a binary cycle that uses isopentane. In last-quarter 1976 dollars, the total estimated capital costs were about $750/kW and production costs about 50 mills/kWhr. If wet/dry towers were used to conserve 50% of the water evaporation at Heber, production costs would be about 65 mills/kWhr.

  19. Development of enhanced sulfur rejection processes

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, R.H.; Luttrell, G.H.; Adel, G.T.; Richardson, P.E.

    1996-03-01

    Research at Virginia Tech led to the development of two complementary concepts for improving the removal of inorganic sulfur from many eastern U.S. coals. These concepts are referred to as Electrochemically Enhanced Sulfur Rejection (EESR) and Polymer Enhanced Sulfur Rejection (PESR) processes. The EESR process uses electrochemical techniques to suppress the formation of hydrophobic oxidation products believed to be responsible for the floatability of coal pyrite. The PESR process uses polymeric reagents that react with pyrite and convert floatable middlings, i.e., composite particles composed of pyrite with coal inclusions, into hydrophilic particles. These new pyritic-sulfur rejection processes do not require significant modifications to existing coal preparation facilities, thereby enhancing their adoptability by the coal industry. It is believed that these processes can be used simultaneously to maximize the rejection of both well-liberated pyrite and composite coal-pyrite particles. The project was initiated on October 1, 1992 and all technical work has been completed. This report is based on the research carried out under Tasks 2-7 described in the project proposal. These tasks include Characterization, Electrochemical Studies, In Situ Monitoring of Reagent Adsorption on Pyrite, Bench Scale Testing of the EESR Process, Bench Scale Testing of the PESR Process, and Modeling and Simulation.

  20. Assessment of antibody mediated cytolysis of adult cardiocytes isolated by centrifugation in a continuous gradient of Percoll in patients with acute myocarditis.

    Science.gov (United States)

    Maisch, B; Trostel-Soeder, R; Berg, P A; Kochsiek, K

    1981-01-01

    Principal objections to conventional cytotoxicity assays in cardiac disease with myocytes as target cells are the use of fetal or neonatal myocardium, the cell-membrane of which does not express all antigenic determinants, and the use of trypsin as enzyme for isolation of the cells, since this alters the myolemmal membrane considerably. An improved and rapid procedure for the isolation of intact adult cardiocytes with collaggenase was developed. by means of a performed continuous self-generating silica sol and gradient centrifugation average enrichment of 81% vital myocytes was achieved by a single isopycnic procedure. The yield was improved to 94 +/- 3% vital cells by identical second centrifugation. Cardiocytes isolated by this method were used as target cells in an assay measuring the cytolytic activity of antibodies in the presence of complement: sera of patients suffering from acute viral myocarditis (Coxsackie B- and influenza-virus) with complement fixing antisacrolemmal antibodies (ASA) of the IgG- and IgM-type showed significant cardiocytolysis. ASA are postulated to play a role in the pathogenesis of acute Coxsackie B- and influenza-virus myocarditis. PMID:6268709

  1. Veto cell suppression mechanisms in the prevention of allograft rejection

    DEFF Research Database (Denmark)

    Jacobsen, I M; Claesson, Mogens Helweg

    1998-01-01

    tolerizing effect of pretransplant donor blood transfusions in kidney graft recipients. A prerequisite for a veto-active environment in vivo is the establishment of lymphoid microchimerism, in which veto-active donor and recipient cells mutually downregulate potential alloaggression.......Substantial evidence has accumulated to suggest that in the near future implementation of the veto-cell-suppressor concept in the treatment of kidney allograft recipients might lead to the establishment of life-long specific allograft tolerance in the absence of further immunosuppressive therapy...... on the surface of the veto-active cell. Data from a large number of experimental and clinical studies strongly indicate that veto-active cells function in vivo and are capable of preventing allograft rejection. Thus, donor-cell-mediated veto activity is the most likely explanation for the well-known graft...

  2. Nuclear Factor κB is Required for Tumor Growth Inhibition Mediated by Enavatuzumab (PDL192), a Humanized Monoclonal Antibody to TweakR.

    Science.gov (United States)

    Purcell, James W; Kim, Han K; Tanlimco, Sonia G; Doan, Minhtam; Fox, Melvin; Lambert, Peter; Chao, Debra T; Sho, Mien; Wilson, Keith E; Starling, Gary C; Culp, Patricia A

    2014-01-01

    TweakR is a TNF receptor family member, whose natural ligand is the multifunctional cytokine TWEAK. The growth inhibitory activity observed following TweakR stimulation in certain cancer cell lines and the overexpression of TweakR in many solid tumor types led to the development of enavatuzumab (PDL192), a humanized IgG1 monoclonal antibody to TweakR. The purpose of this study was to determine the mechanism of action of enavatuzumab's tumor growth inhibition and to provide insight into the biology behind TweakR as a cancer therapeutic target. A panel of 105 cancer lines was treated with enavatuzumab in vitro; and 29 cell lines of varying solid tumor backgrounds had >25% growth inhibition in response to the antibody. Treatment of sensitive cell lines with enavatuzumab resulted in the in vitro and in vivo (xenograft) activation of both classical (p50, p65) and non-classical (p52, RelB) NFκB pathways. Using NFκB DNA binding functional ELISAs and microarray analysis, we observed increased activation of NFκB subunits and NFκB-regulated genes in sensitive cells over that observed in resistant cell lines. Inhibiting NFκB subunits (p50, p65, RelB, p52) and upstream kinases (IKK1, IKK2) with siRNA and chemical inhibitors consistently blocked enavatuzumab's activity. Furthermore, enavatuzumab treatment resulted in NFκB-dependent reduction in cell division as seen by the activation of the cell cycle inhibitor p21 both in vitro and in vivo. The finding that NFκB drives the growth inhibitory activity of enavatuzumab suggests that targeting TweakR with enavatuzumab may represent a novel cancer treatment strategy.

  3. Nuclear Factor κB is required for tumor growth inhibition mediated by enavatuzumab (PDL192, a humanized monoclonal antibody to TweakR

    Directory of Open Access Journals (Sweden)

    James W. Purcell

    2014-01-01

    Full Text Available TweakR is a TNF receptor family member, whose natural ligand is the multifunctional cytokine TWEAK. The growth inhibitory activity observed following TweakR stimulation in certain cancer cell lines and the overexpression of TweakR in many solid tumor types led to the development of enavatuzumab (PDL192, a humanized IgG1 monoclonal antibody to TweakR. The purpose of this study was to determine the mechanism of action of enavatuzumab’s tumor growth inhibition and to provide insight into the biology behind TweakR as a cancer therapeutic target. A panel of 105 cancer lines was treated with enavatuzumab in vitro; and 29 cell lines of varying solid tumor backgrounds had >25% growth inhibition in response to the antibody. Treatment of sensitive cell lines with enavatuzumab resulted in the in vitro and in vivo (xenograft activation of both classical (p50, p65 and non-classical (p52, RelB NFκB pathways. Using NFκB DNA binding functional ELISAs and microarray analysis, we observed increased activation of NFκB subunits and NFκB regulated genes in sensitive cells over that observed in resistant cell lines. Inhibiting NFκB subunits (p50, p65, RelB, p52 and upstream kinases (IKK1, IKK2 with siRNA and chemical inhibitors consistently blocked enavatuzumab’s activity. Furthermore, enavatuzumab treatment resulted in NFκB-dependent reduction in cell-division as seen by the activation of the cell cycle inhibitor p21 both in vitro and in vivo. The finding that NFκB drives the growth inhibitory activity of enavatuzumab suggests that targeting TweakR with enavatuzumab may represent a novel cancer treatment strategy.

  4. Both rejection and tolerance of allografts can occur in the absence of secondary lymphoid tissues.

    Science.gov (United States)

    Kant, Cavit D; Akiyama, Yoshinobu; Tanaka, Katsunori; Shea, Susan; Yamada, Yohei; Connolly, Sarah E; Marino, Jose; Tocco, Georges; Benichou, Gilles

    2015-02-01

    In this study, we showed that aly/aly mice, which are devoid of lymph nodes and Peyer's patches, acutely rejected fully allogeneic skin and heart grafts. They mounted potent inflammatory direct alloresponses but failed to develop indirect alloreactivity after transplantation. Remarkably, skin allografts also were rejected acutely by splenectomized aly/aly (aly/aly-spl(-)) mice devoid of all secondary lymphoid organs. In these recipients, the rejection was mediated by alloreactive CD8(+) T cells presumably primed in the bone marrow. In contrast, cardiac transplants were not rejected by aly/aly-spl(-) mice. Actually, aly/aly-spl(-) mice that spontaneously accepted a heart allotransplant and displayed donor-specific tolerance also accepted skin grafts from the same, but not a third-party, donor via a mechanism involving CD4(+) regulatory T cells producing IL-10 cytokine. Therefore, direct priming of alloreactive T cells, as well as rejection and regulatory tolerance of allogeneic transplants, can occur in recipient mice lacking secondary lymphoid organs.

  5. Expression of Cytokines in Acute Heart Transplantation Rejection

    Institute of Scientific and Technical Information of China (English)

    XIA Jiahong; XU Lei; YANG Chenyuan

    2006-01-01

    The expression and changes of local cytokines network were detected in heart transplantation in rats, so as to determine the role of cytokines in the acute rejection of rats of heart transplantation. Allografts were divided into 4 groups (n=12 in each group): group A (control), group B (IL-2 monoclonal antibody-treated), group C (CsA-treated) and group D (IL-2 monoclonal antibody+CsA-treated). Hearts from DA rats were transplanted into a cervical location in Wistar recipients. The local expression of IL-1β, IL-2, CD25, IL-4, IL-5, IL-6, IL-10, TNFα and INFγ was detected at day 1, 3, 5, 7, 9, 11 and 14 by reverse transcription polymerase chain reaction. The results showed that the survival time of allografts was 8.3±1.7, 29.2±7.1 (P<0.05), 26.4±5.7 (P<0.05) and 55.0±10.6 (P<0.01) days respectively in groups A, B, C and D. The expression of IL-1β, IL-4, IL-10and IFNγ was up-regulated, and that of IL-2, CD25, IL-5, IL-6 and TNFα was significantly inhibited in group A; The expression of IL-1β, IL-5, IL-6, IL-10 and IFNγ was up-regulated, and that of IL-2,IL-4 and TNFα was significantly down-regulated in group B; The expression of IL-1β, IL-2, CD25,IL-5, TNFα and IFNγ was up-regulated, and that of IL-4, IL-6 and IL-10 was significantly down-regulated in group C; The expression of IL-14, Il-5, IL-6 and Il-10 was up-regulated, and that of IL-1β, IL-2, CD25, TNFα and IFNγ was significantly down-regulated in group D. In conclusion,cytokines play an important role in the development of acute transplantation rejection. Different cytokines play different roles in different local environments.

  6. Monitoring of Acute Rejection after Orthotopic Heart Tranplantation

    Institute of Scientific and Technical Information of China (English)

    Meng chun ying; Huang ke li; Luo bin; Wen ding guo

    2006-01-01

    Objectives To study the monitoring of rejection after orthotopic heart thansplantation.Methods From 1998 to 2005, 10 othotopic heart thansplans were performed, and acute rejection was monitored by endomyocardial biopsy as well as by clinical features, ECG, ultrasonocardiography and blood serum determination of Tropin I, and by the combination of these methods, we analysed the monitoring of acute rejection after the heart transplantation. Results With the combination of clinical features, ECG, ultrasonocardiography and blood serum test, 5 occurences of acute rejection were judged in the postoperative course, which were comfirmed by endomyocardial biopsy to be 2 acute rejections in Ⅰ b degree, 3 acute rejections in Ⅲ a degree. Endomyocardial biopsy were routinely performed 21 times postoperatively in which there were 1 acute rejection in Ⅰ a degree and 5 acute rejections in Ⅰ b degree. Conclusions Acute rejection is an important factor influencing the postoperative course of heart transplantation, so it is imperative to have an intime, effective and planned monitoring procedure for acute rejection. Endomyocardial biopsy is a sensitive and reliable method in diagnosis of acute rejection, but it is invasive and probable for some complications. The noninvasive method such as clinical features, ECG,ultrasonocardiography and blood serum test can be used as additive means in the diagnosis of acute rejection.Endomyocardial biopsy should be combined with some noninvasive methods in monitoring acute rejection after the heart transplantation.

  7. New approaches to the management of acute and chronic cardiac allograft rejection

    Energy Technology Data Exchange (ETDEWEB)

    Isobe, Mitsuaki; Suzuki, Jun-ichi [Shinshu Univ., Matsumoto, Nagano (Japan). School of Medicine

    1998-05-01

    There are still many problems to be faced in the field of heart transplantation. Acute and chronic rejection are still the major medical obstacles. In this review, we describe recent research in this field undertaken in our laboratory. The induced intercellular adhesion molecule-1 (ICAM-1) and MHC class II antigen resulting from rejection can be visualized in vivo by radioimmunoscintigraphy. This non-invasive method is sensitive for detecting early rejection and allows quantitative assessment of rejection. Short-term administration of monoclonal antibodies to ICAM-1 and leukocyte function-associated antigen-1 (LFA-1) results in an indefinite acceptance of cardiac allografts by induction of antigen-specific tolerance, as evidenced by acceptance of the secondary skin allografts. The characteristics and possible mechanisms of this tolerance induction are discussed. Immunohistopathologic features of graft coronary arteriopathy are shown. Adhesion molecules, cytokines, and growth factors are associated with intimal hyperplasia and phenotypic transformation of smooth muscle cells in the allograft coronary arteries. Dramatic reduction in this intimal hyperplasia was demonstrated by antisense gene therapy targeting cyclin-dependent kinase 2 kinase. We hope that these investigations will contribute to the improvement of the management of patients who undergo heart transplantation. (author). 117 refs.

  8. Antibody induction therapy for lung transplant recipients

    DEFF Research Database (Denmark)

    Penninga, Luit; Møller, Christian H; Penninga, Ida Elisabeth Irene;

    2013-01-01

    Lung transplantation has become a valuable and well-accepted treatment option for most end-stage lung diseases. Lung transplant recipients are at risk of transplanted organ rejection, and life-long immunosuppression is necessary. Clear evidence is essential to identify an optimal, safe...... and effective immunosuppressive treatment strategy for lung transplant recipients. Consensus has not yet been achieved concerning use of immunosuppressive antibodies against T-cells for induction following lung transplantation....

  9. History of abuse and risky sex among substance users: The role of rejection sensitivity and the need to belong.

    Science.gov (United States)

    Woerner, Jacqueline; Kopetz, Catalina; Lechner, William V; Lejuez, Carl

    2016-11-01

    This study investigates abuse and rejection sensitivity as important correlates of risky sexual behavior in the context of substance use. Victims of abuse may experience heightened sensitivity to acute social rejection and consequently engage in risky sexual behavior in an attempt to restore belonging. Data were collected from 258 patients at a substance use treatment facility in Washington, D.C. Participants' history of abuse and risky sexual behavior were assessed via self-report. To test the mediating role of rejection sensitivity, participants completed a social rejection task (Cyberball) and responded to a questionnaire assessing their reaction to the rejection experience. General risk-taking propensity was assessed using a computerized lab measure. Abuse was associated with increased rejection sensitivity (B=0.124, SE=0.040, p=0.002), which was in turn associated with increased risky sex (B=0.06, SE=0.028, p=0.03) (indirect effect=0.0075, SE=0.0043; 95% CI [0.0006, 0.0178]), but not with other indices of risk-taking. These findings suggest that rejection sensitivity may be an important mechanism underlying the relationship between abuse and risky sexual behavior among substance users. These effects do not extend to other risk behaviors, supporting the notion that risky sex associated with abuse represents a means to interpersonal connection rather than a general tendency toward self-defeating behavior. PMID:27344009

  10. Chronic Kidney Isograft and Allograft Rejection

    Institute of Scientific and Technical Information of China (English)

    严群; 张鹏; 杨传永

    2002-01-01

    Summary: In this study antigen-independent factor in the pathogenesis of chronic rejection of organ transplants was examined. Kidney isografts and allografts were transplanted orthotopically into bilaterally nephroectomized rat recipients and studied functionally, morphologically and immunohistologically, at serial intervals up to 52 weeks after transplantation. Allograft recipients developed progressive proteinuria after 12 weeks, with gradual renal failure ultimately leading to death. At the same time, morphological changes, including progressive arteriosclerosis and glomerulosclerosis, tubular atrophy and interstitial fibrosis, developed. Immunohistologically, macrophages infiltrated glomeruli during this period and cytokines became unregulated. Our resuits showed that antigen-independent functional and morphological changes occurred in long-term kidney isografts and mimicked those appearing much earlier in allografts that reject chronically.Initial injury and extent of functioning renal mass is suggested to be important factor for such late changes.

  11. Interference Rejection Techniques in DSSS Communication System

    Institute of Scientific and Technical Information of China (English)

    GONGXiangyang; HUGuangrui

    2003-01-01

    It is known that the narrowband interfer-ence rejection capability of a direct sequence (DS) spread spectrum (SS) system can be enhanced considerably by an interference rejection algorithm prior to correlating it with the pseudo noise (PN) sequence. For narrowband gaussian noise (NGN), the techniques in common use are transver-sal filter. It models SS signal and NGN as stationary, then utilizes temporal correlation difference between SS signal and NBL however, SS signal and NGN are cyclostation-ary (CS). CS signal has correlation in frequency domain called spectrum correlation, which can not be employed by transversal filter. In this article, SS signal and NBIare modeled as CS and FRESH filter is adopted to exploit the correlation both in time domain and frequency domain.Computer simulation shows that FRESH filter can improve the system performance considerably compared with con-ventional transversal filter.

  12. Autophagy in allografts rejection: A new direction?

    Science.gov (United States)

    Sun, Hukui; Cheng, Dayan; Ma, Yuanyuan; Wang, Huaiquan; Liang, Ting; Hou, Guihua

    2016-03-18

    Despite the introduction of new and effective immunosuppressive drugs, acute cellular graft rejection is still a major risk for graft survival. Modulating the dosage of immunosuppressive drugs is not a good choice for all patients, new rejection mechanisms discovery are crucial to limit the inflammatory process and preserve the function of the transplant. Autophagy, a fundamental cellular process, can be detected in all subsets of lymphocytes and freshly isolated naive T lymphocytes. It is required for the homeostasis and function of T lymphocytes, which lead to cell survival or cell death depending on the context. T cell receptor (TCR) stimulation and costimulator signals induce strong autophagy, and autophagy deficient T cells leads to rampant apoptosis upon TCR stimulation. Autophagy has been proved to be activated during ischemia-reperfusion (I/R) injury and associated with grafts dysfunction. Furthermore, Autophagy has also emerged as a key mechanism in orchestrating innate and adaptive immune response to self-antigens, which relates with negative selection and Foxp3(+) Treg induction. Although, the role of autophagy in allograft rejection is unknown, current data suggest that autophagy indeed sweeps across both in the graft organs and recipients lymphocytes after transplantation. This review presents the rationale for the hypothesis that targeting the autophagy pathway could be beneficial in promoting graft survival after transplantation.

  13. THE DIAGNOSIS OF LIVER ALLOGRAFT ACUTE REJECTION IN LIVER BIOPSIES

    Directory of Open Access Journals (Sweden)

    L. V. Shkalova

    2011-01-01

    Full Text Available We performed histological examination of 80 liver allograft biopsies, the diagnosis of acute rejection was proved in 34 cases. Histological changes in liver biopsies in different grades of acute rejection were estimated according to Banff classification 1995, 1997 and were compared with current literature data. The article deals with the question of morphological value of grading acute rejection on early and late, also we analyze changes in treat- ment tactics after morphological verification of liver allograft acute rejection

  14. Spontaneous restoration of transplantation tolerance after acute rejection

    OpenAIRE

    Miller, Michelle L.; Daniels, Melvin D.; Wang, Tongmin; Chen, Jianjun; Young, James; Xu, Jing; Wang, Ying; Yin, Dengping; Vu, Vinh; Husain, Aliya N.; Alegre, Maria-Luisa; Chong, Anita S.

    2015-01-01

    Transplantation is a cure for end-stage organ failure but, in the absence of pharmacological immunosuppression, allogeneic organs are acutely rejected. Such rejection invariably results in allosensitization and accelerated rejection of secondary donor-matched grafts. Transplantation tolerance can be induced in animals and a subset of humans, and enables long-term acceptance of allografts without maintenance immunosuppression. However, graft rejection can occur long after a state of transplant...

  15. Predicting outcome of acute kidney transplant rejection using

    NARCIS (Netherlands)

    Rekers, Niels Vincent

    2014-01-01

    Acute kidney transplant rejection is an important risk factors for adverse graft outcome. Once diagnosed, it remains difficult to predict the risk of graft loss and the response to anti-rejection treatment. The aim of this thesis was to identify biomarkers during acute rejection, which predict the r

  16. Pronounced antitumor efficacy by extracellular activation of a doxorubicin-glucuronide prodrug after adenoviral vector-mediated expression of a human antibody-enzyme fusion protein.

    Science.gov (United States)

    de Graaf, Michelle; Pinedo, Herbert M; Oosterhoff, Dinja; van der Meulen-Muileman, Ida H; Gerritsen, Winald R; Haisma, Hidde J; Boven, Epie

    2004-03-01

    Tumor-specific activation of the glucuronide prodrug of doxorubicin, N-[4-doxorubicin-N-carbonyl(oxymethyl)phenyl]-O-beta-glucuronyl carbamate (DOX-GA3), by beta-glucuronidase present in necrotic tumor areas might be improved after transduction of tumor cells to secrete a targeted form of beta-glucuronidase. To that end, we constructed an adenovirus vector, designated Ad/C28-GUSh, encoding human beta-glucuronidase fused to a human single-chain Fv (scFv) against the epithelial cell adhesion molecule (EpCAM), C28, and preceded by a signal sequence for secretion. Antibody specificity and enzyme activity were retained in the fusion protein secreted by tumor cells infected with Ad/C28-GUSh. Diffusion of fusion protein from transduced tumor cells within MCF-7 multicellular spheroids was visualized by immunohistochemistry. Treatment of spheroids with Ad/C28-GUSh and DOX-GA3 resulted in growth inhibition comparable to treatment with doxorubicin alone. Treatment of well-established FMa human ovarian cancer xenografts with intravenous injection of DOX-GA3 (500 mg/kg) resulted in a tumor volume-doubling time of 23.8 days compared to 8.0 days for phosphate-buffered saline (PBS)-treated mice. Intratumoral administration of Ad/C28-GUSh before DOX-GA3 enhanced the growth inhibition and increased the tumor volume-doubling time to 43.1 days (p targeted form of human beta-glucuronidase can further improve DOX-GA3 monotherapy.

  17. The HB22.7 Anti-CD22 monoclonal antibody enhances bortezomib-mediated lymphomacidal activity in a sequence dependent manner

    Directory of Open Access Journals (Sweden)

    Martin Shiloh M

    2011-12-01

    Full Text Available Abstract Most non-Hodgkin's lymphomas (NHL initially respond to chemotherapy, but relapse is common and treatment is often limited by chemotherapy-related toxicity. Bortezomib, is a highly selective proteasome inhibitor with anti-NHL activity; it is currently FDA approved for second-line treatment of mantle cell lymphoma (MCL. Bortezomib exerts its activity in part through the generation of reactive oxygen species (ROS and also by the induction of apoptosis. We previously validated CD22 as a potential target in treating NHL and have shown that the anti-CD22 ligand blocking antibody, HB22.7, has significant independent lymphomacidal properties in NHL xenograft models. We sought to determine whether or not these agents would work synergistically to enhance cytotoxicity. Our results indicate that treatment of NHL cell lines with HB22.7 six hours prior to bortezomib significantly diminished cell viability. These effects were not seen when the agents were administered alone or when bortezomib was administered prior to HB22.7. Additionally, HB22.7 treatment prior to bortezomib increased apoptosis in part through enhanced ROS generation. Finally, in a mouse xenograft model, administration of HB22.7 followed 24 hours later by bortezomib resulted in 23% smaller tumor volumes and 20% enhanced survival compared to treatment with the reverse sequence. Despite the increased efficacy of HB22.7 treatment followed by bortezomib, there was no corresponding decrease in peripheral blood cell counts, indicating no increase in toxicity. Our results suggest that pre-treatment with HB22.7 increases bortezomib cytotoxicity, in part through increased reactive oxygen species and apoptosis, and that this sequential treatment combination has robust efficacy in vivo.

  18. Developmental pathways from childhood aggression-disruptiveness, chronic peer rejection, and deviant friendships to early-adolescent rule breaking.

    Science.gov (United States)

    Ettekal, Idean; Ladd, Gary W

    2015-01-01

    Childhood aggression-disruptiveness (AD), chronic peer rejection, and deviant friendships were examined as predictors of early-adolescent rule-breaking behaviors. Using a sample of 383 children (193 girls and 190 boys) who were followed from ages 6 to 14, peer rejection trajectories were identified and incorporated into a series of alternative models to assess how chronic peer rejection and deviant friendships mediate the association between stable childhood AD and early-adolescent rule breaking. There were multiple mediated pathways to rule breaking that included both behavioral and relational risk factors, and findings were consistent for boys and girls. Results have implications for better understanding the influence of multiple social processes in the continuity of antisocial behaviors from middle childhood to early adolescence. PMID:25403544

  19. High throughput screening for antibody induced complement-dependent cytotoxicity in early antibody discovery using homogeneous macroconfocal fluorescence imaging

    NARCIS (Netherlands)

    Gerritsen, Arnout F.; Bosch, Martijn; de Weers, Michel; van de Winkel, Jan G. J.; Parren, Paul W. H. I.

    2010-01-01

    Complement-dependent cytotoxicity (CDC) represents an important Fc-mediated effector function of antibodies and is a quality often sought in candidates for therapeutic antibody development in cancer. Antibodies inducing potent CDC are relatively rare as the ability to induce CDC is strongly dependen

  20. Banff study of pathologic changes in lung allograft biopsy specimens with donor-specific antibodies

    DEFF Research Database (Denmark)

    Wallace, William Dean; Li, Ning; Andersen, Claus B;

    2016-01-01

    -DSAs, and no antibodies (NABs) present. The significance of each histologic variable was reviewed. RESULTS: We found no statistically significant association with acute cellular rejection, airway inflammation, or bronchiolitis obliterans and the presence or absence of antibodies. However, biopsy specimens with DSAs had...

  1. Generation of suppressive blood cells for control of allograft rejection.

    Science.gov (United States)

    Kleist, Christian; Sandra-Petrescu, Flavius; Jiga, Lucian; Dittmar, Laura; Mohr, Elisabeth; Greil, Johann; Mier, Walter; Becker, Luis E; Lang, Peter; Opelz, Gerhard; Terness, Peter

    2015-05-01

    Our previous studies in rats showed that incubation of monocytic dendritic cells (DCs) with the chemotherapeutic drug mitomycin C (MMC) renders the cells immunosuppressive. Donor-derived MMC-DCs injected into the recipient prior to transplantation prolonged heart allograft survival. Although the generation of DCs is labour-intensive and time-consuming, peripheral blood mononuclear cells (PBMCs) can be easily harvested. In the present study, we analyse under which conditions DCs can be replaced by PBMCs and examine their mode of action. When injected into rats, MMC-incubated donor PBMCs (MICs) strongly prolonged heart allograft survival. Removal of monocytes from PBMCs completely abrogated their suppressive effect, indicating that monocytes are the active cell population. Suppression of rejection was donor-specific. The injected MICs migrated into peripheral lymphoid organs and led to an increased number of regulatory T-cells (Tregs) expressing cluster of differentiation (CD) markers CD4 and CD25 and forkhead box protein 3 (FoxP3). Tolerance could be transferred to syngeneic recipients with blood or spleen cells. Depletion of Tregs from tolerogenic cells abrogated their suppressive effect, arguing for mediation of immunosuppression by CD4⁺CD25⁺FoxP3⁺ Tregs. Donor-derived MICs also prolonged kidney allograft survival in pigs. MICs generated from donor monocytes were applied for the first time in humans in a patient suffering from therapy-resistant rejection of a haploidentical stem cell transplant. We describe, in the present paper, a simple method for in vitro generation of suppressor blood cells for potential use in clinical organ transplantation. Although the case report does not allow us to draw any conclusion about their therapeutic effectiveness, it shows that MICs can be easily generated and applied in humans.

  2. Use of a SQUID array to detect T-cells with magnetic nanoparticles in determining transplant rejection

    Energy Technology Data Exchange (ETDEWEB)

    Flynn, Edward R. [Senior Scientific, 11109 Country Club NE, Albuquerque, NM 87111 (United States)]. E-mail: seniorsci@nmia.com; Bryant, H.C. [Senior Scientific, 11109 Country Club NE, Albuquerque, NM 87111 (United States); Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131 (United States); Bergemann, Christian [Chemicell GmbH, Berlin (Germany); Larson, Richard S. [Cancer Research and Treatment Center, University of New Mexico, Albuquerque, NM 87131 (United States); Lovato, Debbie [Cancer Research and Treatment Center, University of New Mexico, Albuquerque, NM 87131 (United States); Sergatskov, Dmitri A. [Senior Scientific, 11109 Country Club NE, Albuquerque, NM 87111 (United States)

    2007-04-15

    Acute rejection in organ transplant is signaled by the proliferation of T-cells that target and kill the donor cells requiring painful biopsies to detect rejection onset. An alternative non-invasive technique is proposed using a multi-channel superconducting quantum interference device (SQUID) magnetometer to detect T-cell lymphocytes in the transplanted organ labeled with magnetic nanoparticles conjugated to antibodies specifically attached to lymphocytic ligand receptors. After a magnetic field pulse, the T-cells produce a decaying magnetic signal with a characteristic time of the order of a second. The extreme sensitivity of this technique, 10{sup 5} cells, can provide early warning of impending transplant rejection and monitor immune-suppressive chemotherapy.

  3. Use of a SQUID array to detect T-cells with magnetic nanoparticles in determining transplant rejection

    International Nuclear Information System (INIS)

    Acute rejection in organ transplant is signaled by the proliferation of T-cells that target and kill the donor cells requiring painful biopsies to detect rejection onset. An alternative non-invasive technique is proposed using a multi-channel superconducting quantum interference device (SQUID) magnetometer to detect T-cell lymphocytes in the transplanted organ labeled with magnetic nanoparticles conjugated to antibodies specifically attached to lymphocytic ligand receptors. After a magnetic field pulse, the T-cells produce a decaying magnetic signal with a characteristic time of the order of a second. The extreme sensitivity of this technique, 105 cells, can provide early warning of impending transplant rejection and monitor immune-suppressive chemotherapy

  4. Two cases of hepatobiliary scintigraphy of liver transplantation in rejection

    Energy Technology Data Exchange (ETDEWEB)

    Kanegawa, Kimio; Nishiyama, Syouji; Muraji, Toshihiro (Kobe Children' s Hospital, Hyogo (Japan)); Ishii, Kazunari; Kouno, Michio

    1992-04-01

    We report two patients with liver transplantation who underwent hepatobiliary scintigraphy in rejection. In the first patient, hepatobiliary scintigraphy showed dilatation of bile duct but it showed good clearance from the liver. In the second patient, hepatobiliary scintigraphy showed delayed clearance from the liver. Both patients recovered from rejection. There were four main complications, including vascular and biliary abnormality, infection, and rejection, after liver transplantation. Hepatobiliary scintigraphy showed almost the same findings except for biliary complication, so it was difficult to distinguish between infection and rejection. But hepatobiliary scintigraphy may be useful to evaluate transplanted liver function in rejection. (author).

  5. Two cases of hepatobiliary scintigraphy of liver transplantation in rejection

    International Nuclear Information System (INIS)

    We report two patients with liver transplantation who underwent hepatobiliary scintigraphy in rejection. In the first patient, hepatobiliary scintigraphy showed dilatation of bile duct but it showed good clearance from the liver. In the second patient, hepatobiliary scintigraphy showed delayed clearance from the liver. Both patients recovered from rejection. There were four main complications, including vascular and biliary abnormality, infection, and rejection, after liver transplantation. Hepatobiliary scintigraphy showed almost the same findings except for biliary complication, so it was difficult to distinguish between infection and rejection. But hepatobiliary scintigraphy may be useful to evaluate transplanted liver function in rejection. (author)

  6. CURRENT VIEW ON MORPHOLOGY OF ACUTE REJECTION IN LIVER TRANSPLANTATION

    Directory of Open Access Journals (Sweden)

    L.V. Shkalova

    2012-01-01

    Full Text Available We present a scientific literature data analysis of morphological features and severity criteria of the liver allograft acute rejection during last 20 years. Modern conception was given about the role of immunological mechanisms in the de- velopment of liver graft acute rejection. We describe roles of different cell types in the destructive immune response during liver allograft acute rejection. Advantages and disadvantages of Banff-classifications 1995, 1997 are discussed as well as the necessity of grading the acute rejection as early and late. We propose clinico-morphological correlations in liver allograft acute rejection

  7. USA: California rejects mandatory GMO labelling

    OpenAIRE

    Paull, John

    2012-01-01

    Buying organic remains the best strategy for US consumers to avoid eating GM food. The voters of California have rejected the proposal to label GMO food. The proposition was narrowly lost, 47% to 53% (4,326,770 ‘Yes’ votes vs. 4,884,961 ‘No’ votes). Proposition 47 was supported by the organic sector but opposed by a coalition of GMO companies and US multinational food companies. Californians were invited to vote into law ‘The California Right to Know Genetically Engineered Food Act’. Section ...

  8. Lentivirus IL-10 gene therapy down-regulates IL-17 and attenuates mouse orthotopic lung allograft rejection.

    Science.gov (United States)

    Hirayama, S; Sato, M; Loisel-Meyer, S; Matsuda, Y; Oishi, H; Guan, Z; Saito, T; Yeung, J; Cypel, M; Hwang, D M; Medin, J A; Liu, M; Keshavjee, S

    2013-06-01

    The purpose of the study was to examine the effect of lentivirus-mediated IL-10 gene therapy to target lung allograft rejection in a mouse orthotopic left lung transplantation model. IL-10 may regulate posttransplant immunity mediated by IL-17. Lentivirus-mediated trans-airway luciferase gene transfer to the donor lung resulted in persistent luciferase activity up to 6 months posttransplant in the isograft (B6 to B6); luciferase activity decreased in minor-mismatched allograft lungs (B10 to B6) in association with moderate rejection. Fully MHC-mismatched allograft transplantation (BALB/c to B6) resulted in severe rejection and complete loss of luciferase activity. In minor-mismatched allografts, IL-10-encoding lentivirus gene therapy reduced the acute rejection score compared with the lentivirus-luciferase control at posttransplant day 28 (3.0 ± 0.6 vs. 2.0 ± 0.6 (mean ± SD); p = 0.025; n = 6/group). IL-10 gene therapy also significantly reduced gene expression of IL-17, IL-23, and retinoic acid-related orphan receptor (ROR)-γt without affecting levels of IL-12 and interferon-γ (IFN-γ). Cells expressing IL-17 were dramatically reduced in the allograft lung. In conclusion, lentivirus-mediated IL-10 gene therapy significantly reduced expression of IL-17 and other associated genes in the transplanted allograft lung and attenuated posttransplant immune responses after orthotopic lung transplantation. PMID:23601206

  9. Effects of Positive Peer Reporting (PPR) on Social Acceptance and Negative Behaviors among Peer-Rejected Preschool Children

    Science.gov (United States)

    Smith, Shelia M.; Simon, Joan; Bramlett, Ronald K.

    2009-01-01

    Positive peer reporting (PPR) is a peer-mediated intervention that involves teaching and rewarding peers for providing descriptive praise during structured daily sessions. PPR has been used in residential facilities to improve social acceptance, increase prosocial behaviors, and decrease negative interactions of youth identified as peer rejected.…

  10. [Diagnosis of rejection in a transplanted liver].

    Science.gov (United States)

    Sticová, Eva; Honsová, Eva

    2015-01-01

    Despite advances in immunosupressive therapy rejection remains the most common complication of liver transplantation in both the early and the late post-transplant period. Unlike other solid organs, liver graft rejection has some specific characteristics likely attributable to the unique immunobiologic properties and the remarkable regenerative capabilities of liver parenchyma. Acute cellular rejection is the most frequent type of the rejection episode in the liver allograft, whereas chronic (ductopenic) rejection and humoral rejection are uncommon. Since the clinical findings are not entirely characteristic, histopathological evaluation of liver biopsy remains the gold standard in the diagnosis of rejection. However, the close cooperation between the pathologist and the clinician is essential for the correct interpretation of morphologic changes.

  11. Tumor-associated antigens identified by mRNA expression profiling as tumor rejection epitopes

    DEFF Research Database (Denmark)

    Andersen, Marie Louise; Ruhwald, Morten; Thorn, Mette;

    2003-01-01

    immunization, but only two of these peptides (RAD23-31 and RAD24-31) were capable of generating a weak vaccination-induced protection against adoptive tumor growth. SM7 inoculated mice treated with a blocking antibody against the inhibitory T cell signal transducing molecule CTLA4 appeared to delay tumor take...... derived from potentially overexpressed tumor proteins, as identified by mRNA expression profiling of p53-/- thymoma cells, at best results in a weak tumor protection thus questioning this way of detection of new tumor rejection epitopes....

  12. A recombinant, fully human monoclonal antibody with antitumor activity constructed from phage-displayed antibody fragments

    NARCIS (Netherlands)

    Huls, GA; Heijnen, IAFM; Cuomo, ME; Koningsberger, JC; Boel, E; de Vries, ARV; Loyson, SAJ; Helfrich, W; Henegouwen, GPV; van Meijer, M; de Kruif, J; Logtenberg, T

    1999-01-01

    A single-chain Fv antibody fragment specific for the tumor-associated Ep-CAM molecule was isolated from a semisynthetic phage display library and converted into an intact, fully human IgG1 monoclonal antibody (huMab), The purified huMab had an affinity of 5 nM and effectively mediated tumor cell kil

  13. Antibody-mediated immune suppression of erythrocyte alloimmunization can occur independently from red cell clearance or epitope masking in a murine model.

    Science.gov (United States)

    Yu, Honghui; Stowell, Sean R; Bernardo, Lidice; Hendrickson, Jeanne E; Zimring, James C; Amash, Alaa; Uchikawa, Makoto; Lazarus, Alan H

    2014-09-15

    Anti-D can prevent immunization to the RhD Ag on RBCs, a phenomenon commonly termed Ab-mediated immune suppression (AMIS). The most accepted theory to explain this effect has been the rapid clearance of RBCs. In mouse models using SRBC, these xenogeneic cells are always rapidly cleared even without Ab, and involvement of epitope masking of the SRBC Ags by the AMIS-inducing Ab (anti-SRBC) has been suggested. To address these hypotheses, we immunized mice with murine transgenic RBCs expressing the HOD Ag (hen egg lysozyme [HEL], in sequence with ovalbumin, and the human Duffy transmembrane protein) in the presence of polyclonal Abs or mAbs to the HOD molecule. The isotype, specificity, and ability to induce AMIS of these Abs were compared with accelerated clearance as well as steric hindrance of the HOD Ag. Mice made IgM and IgG reactive with the HEL portion of the molecule only. All six of the mAbs could inhibit the response. The HEL-specific Abs (4B7, IgG1; GD7, IgG2b; 2F4, IgG1) did not accelerate clearance of the HOD-RBCs and displayed partial epitope masking. The Duffy-specific Abs (MIMA 29, IgG2a; CBC-512, IgG1; K6, IgG1) all caused rapid clearance of HOD RBCs without steric hindrance. To our knowledge, this is the first demonstration of AMIS to erythrocytes in an all-murine model and shows that AMIS can occur in the absence of RBC clearance or epitope masking. The AMIS effect was also independent of IgG isotype and epitope specificity of the AMIS-inducing Ab. PMID:25122924

  14. Uremic escape of renal allograft rejection

    Energy Technology Data Exchange (ETDEWEB)

    van Schilfgaarde, R. (Rijksuniversiteit Leiden (Netherlands). Academisch Ziekenhuis); van Breda Vriesman, P.J.C. (Rijksuniversiteit Limburg Maastricht (Netherlands). Dept. of Immunopathology)

    1981-10-01

    It is demonstrated in rats that, in the presence of early postoperative severe but transient uremia, the survival of first set Brown-Norway (BN) renal allografts in Lewis (LEW) recipients is at least three times prolonged when compared to non-uremic controls. This phenomenon is called 'uremic escape of renal allograft rejection'. By means of lethal X-irradiation of donors of BN kidneys transplanted into transiently uremic and non-uremic LEW recipients, the presence of passenger lymphocyte immunocompetence is demonstrated to be obilgatory for this phenomenon to occur. As a result of mobile passenger lymphocyte immunocompetence, a graft-versus-host (GVH) reaction is elicited in the spleens of LEW recipients of BN kidneys which amplifies the host response. The splenomegaly observed in LEW recipients of BN kidneys is caused not only by this GVH reaction, which is shown to be exquisitely sensitive to even mild uremia. It is also contributed to by a proliferative response of the host against the graft (which latter response is equated with an in vivo equivalent of a unilateral mixed lymphocyte reaction (MLR)), since the reduction in spleen weights caused by abrogation of mobile passenger lymphocyte immunocompetence brought about by lethal donor X-irradiation is increased significantly by early postoperative severe but transient uremia. It is concluded that in uremic escape of renal allograft rejection both reactions are suppressed by uremia during the early post-operative period.

  15. Altered glycosylation in donor mice causes rejection of strain-matched skin and heart grafts.

    Science.gov (United States)

    Gock, H; Murray-Segal, L J; Winterhalter, A C; Aminian, A; Moore, G T C; Brown, S J; d'Apice, A J F; Cowan, P J

    2014-04-01

    Differential protein glycosylation in the donor and recipient can have profound consequences for transplanted organs, as evident in ABO-incompatible transplantation and xenotransplantation. In this study, we investigated the impact of altered fucosylation on graft acceptance by using donor mice overexpressing human α1,2-fucosyltransferase (HTF). Skin and heart grafts from HTF transgenic mice were rapidly rejected by otherwise completely matched recipients (median survival times 16 and 14 days, respectively). HTF skin transplanted onto mice lacking T and B cells induced an natural killer cell-mediated innate rejection crisis that affected 50-95% of the graft at 10-20 days. However, in the absence of adaptive immunity, the residual graft recovered and survived long-term (>100 days). Experiments using "parked" grafts or MHC class II-deficient recipients suggested that indirect rather than direct antigen presentation plays a role in HTF skin graft rejection, although the putative antigen(s) was not identified. We conclude that altered glycosylation patterns on donor tissue can trigger a powerful rejection response comprising both innate and adaptive components. This has potential implications for allotransplantation, in light of increasing recognition of the variability of the human glycome, and for xenotransplantation, where carbohydrate remodeling has been a lynchpin of donor genetic modification.

  16. Research on the prevention of splenic graft rejection in vitro with anti-dendritic cell monoclonal antibody%应用树突状细胞单克隆抗体预防脾移植排斥反应的实验研究

    Institute of Scientific and Technical Information of China (English)

    周艳娟; 陈天宇

    2001-01-01

    Objective To reduce immunogenicity of the donor spleen,a rat model of continuous perfusion of graft was established with therapeutic anti-dendritic cells monoclonal antibody(WZD).Methods We perfused donor rat spleens continuously with WZD and selected the best protocol among them,then we examined lymphopoiesis by mixed lymphocyte culture (MLC) and observed ultrastructure of donor splenocytes.Results Perfusion alone significantly depressed the ability of lymphopoiesis(P0.05).The function of splenocyte in graft which perfused at 21℃ was more active,and the mitochondrial injury was slight.Conclusion The best effect can be obtained by perfusion with WZD at a speed of 50ml/h at 21℃.Pretransplant perfusion of the spleen with WZD may reduce the immunogenicity of the graft and the dosage of immunosuppressant.%目的建立治疗性单克隆抗体溶液持续器官灌注模型,应用抗大鼠树突状细胞单克隆抗体(WZD)降低大鼠移植脾的免疫原性.方法以WZD溶液持续灌注移植脾,筛选最佳方案,并观察灌注后混合淋巴细胞培养(mixed lymphocyte culture,MLC)中淋巴细胞的增殖情况及灌注后移植脾细胞的超微结构.结果 WZD灌注组MLC淋巴细胞增殖能力明显降低,与对照组及应用环孢霉素A(Cyclosporin A,CsA)组相比差异显著(P0.05),21℃灌注组移植脾细胞功能活跃,线粒体损伤小.结论移植脾在21℃下,每小时给予灌注50ml单抗溶液获得了最佳效果,WZD溶液灌注移植脾,可去除树突状细胞,确能降低其免疫原性,有可能减少免疫抑制剂的应用剂量.

  17. The role of CD8+ T cells during allograft rejection

    Directory of Open Access Journals (Sweden)

    Bueno V.

    2002-01-01

    Full Text Available Organ transplantation can be considered as replacement therapy for patients with end-stage organ failure. The percent of one-year allograft survival has increased due, among other factors, to a better understanding of the rejection process and new immunosuppressive drugs. Immunosuppressive therapy used in transplantation prevents activation and proliferation of alloreactive T lymphocytes, although not fully preventing chronic rejection. Recognition by recipient T cells of alloantigens expressed by donor tissues initiates immune destruction of allogeneic transplants. However, there is controversy concerning the relative contribution of CD4+ and CD8+ T cells to allograft rejection. Some animal models indicate that there is an absolute requirement for CD4+ T cells in allogeneic rejection, whereas in others CD4-depleted mice reject certain types of allografts. Moreover, there is evidence that CD8+ T cells are more resistant to immunotherapy and tolerance induction protocols. An intense focal infiltration of mainly CD8+CTLA4+ T lymphocytes during kidney rejection has been described in patients. This suggests that CD8+ T cells could escape from immunosuppression and participate in the rejection process. Our group is primarily interested in the immune mechanisms involved in allograft rejection. Thus, we believe that a better understanding of the role of CD8+ T cells in allograft rejection could indicate new targets for immunotherapy in transplantation. Therefore, the objective of the present review was to focus on the role of the CD8+ T cell population in the rejection of allogeneic tissue.

  18. Monoclonal antibodies

    International Nuclear Information System (INIS)

    Monoclonal antibodies (MAbs) are antibodies having single specificity for a given antigen site (epitope). The development of hybridoma technology and the relative ease by which MAbs can be prepared has revolutionized many aspects of serological applications in diagnosis and differentiation of disease producing agents. The property of monospecificity offers advantages in diagnostic applications over polyclonal sera in that tests can be defined exactly with regard to the antigen detected and the affinity of reaction between the given antigenic site and the monoclonal reagent. In addition, MAbs offer better possibilities for test standardization, because the same reagent can be used in different laboratories. Such an MAb can be supplied by a central laboratory or 'grown' from hybridoma cells, ensuring that the resultant product is identical from laboratory to laboratory and that the part of the test involving the MAb reaction is the same. The methodologies for inoculation regimes, mice, cloning methods, selection of fusion partners, etc., have been validated extensively in developed country laboratories. The decision to establish a MAb production facility must be examined on a strict cost-benefit basis, since it is still expensive to produce a product. There are many MAbs available that should be sought to allow exploitation in developing tests. If a production facility is envisaged, it should produce reagents for national needs, i.e. there should be a clear problem oriented approach whereby exact needs are defined. In the field of veterinary applications, MAbs are the central reagent in many immunoassays based on the enzyme linked immunosorbent assay (ELISA). The development of specific tests for diagnosing diseases is dominated by MAbs and has been fuelled by a strong research base, mainly in developed countries allied to developing countries through the study of related diseases. Thus, there are very many assays dependent on MAbs, some of which form the basis of

  19. Anti-interleukin-2 receptor antibodies—basiliximab and daclizumab—for the prevention of acute rejection in renal transplantation

    Directory of Open Access Journals (Sweden)

    Junichiro Sageshima

    2009-06-01

    Full Text Available Junichiro Sageshima, Gaetano Ciancio, Linda Chen, George W Burke IIIDewitt Daughtry Family Department of Surgery, Division of Kidney and Pancreas Transplantation, The Lillian Jean Kaplan Renal Transplant Center, University of Miami Leonard M. Miller School of Medicine, Miami, FL, USAAbstract: The use of antibody induction after kidney transplantation has increased from 25% to 63% in the past decade and roughly one half of the induction agent used is anti-interleukin-2 receptor antibody (IL-2RA, ie, basiliximab or daclizumab. When combined with calcineurin inhibitor (CNI-based immunosuppression, IL-2RAs have been shown to reduce the incidence of acute rejection, one of the predictors of poor graft survival, without increasing risks of infections and malignancies in kidney transplantation. For low-immunological-risk patients, IL-2RAs, as compared with lymphocyte-depleting antibodies, are equally efficacious and have better safety profiles. For high-risk patients, however, IL-2RAs may be inferior to lymphocyte-depleting antibodies for the prophylaxis of acute rejection. In an effort to reduce toxicities of other immunosuppressive medications without increasing the risk of acute rejection and chronic graft loss, IL-2RAs have often been combined with steroid- and CNI-sparing immunosuppression protocols. More data support the benefits of early steroid withdrawal with IL-2RA in low-risk patients, but preferred induction therapy for high-risk patients has yet to be determined. Although CNI-sparing protocols with IL-2RA may preserve renal function and improve long-term survival in selected patients, further studies are needed to identify those who benefit most from this strategy.Keywords: basiliximab, daclizumab, interleukin-2 receptor antagonist, kidney transplantation, monoclonal antibody

  20. The Rejection-Rage Contingency in Borderline Personality Disorder

    Science.gov (United States)

    Berenson, Kathy R.; Downey, Geraldine; Rafaeli, Eshkol; Coifman, Karin; Leventhal, Nina

    2011-01-01

    Though longstanding clinical observation reflected in the DSM-IV suggests that the rage characteristic of borderline personality disorder (BPD) often appears in response to perceived rejection, the role of perceived rejection in triggering rage in BPD has never been empirically tested. Extending basic personality research on rejection sensitivity to a clinical sample, a priming-pronunciation experiment and a 21-day experience-sampling diary examined the contingent relationship between perceived rejection and rage in participants diagnosed with BPD compared to healthy controls. Despite the differences in these two assessment methods, the indices of rejection-contingent rage that they produced were both elevated in the BPD group, and were strongly interrelated. They provide corroborating evidence that reactions to perceived rejection significantly explain the rage seen in BPD. PMID:21500875

  1. Multivisceral transplantation in pigs: a clinicopathological analysis of tissue rejection.

    Directory of Open Access Journals (Sweden)

    Mitsuoka,Shintaro

    1995-10-01

    Full Text Available In this study, we established the surgical procedure and postoperative care of multivisceral transplantation (MVTX in pigs, and examined the functional changes and rejection pattern of transplanted organs in MVTX. Twenty-two MVTXs were performed without immunosuppression, and nine cases (41% that survived for 5 days or more after MVTX were used for evaluation. Rejection in grafts including the liver, pancreas, and gastrointestinal tract were assessed histopathologically. On day 5 after transplantation, the duodenum and small bowel already showed signs of mild rejection. On the other hand, in the liver, pancreas and stomach, rejection occurred later and was still mild on day 16. Hepatic rejection in MVTX appeared to occur later than in simple liver transplantation (LTX. These results showed that the susceptibility to rejection of individual visceral organs varies.

  2. Successful kidney transplantation after desensitization in a patient with positive flow crossmatching and donor-specific anti-HLA-DP antibody

    Science.gov (United States)

    Song, Seung Hwan; Park, Borae G.; Lee, Juhan; Kim, Myoung Soo; Kim, Yu Seun; Kim, Hyon-Suk

    2016-01-01

    Abstract Background: Traditionally, the presence of antibodies against human leukocyte antigen (HLA)-C and DP was considered to be associated with only a low risk of antibody-mediated rejection (ABMR) in kidney transplantation (KT), because the antigenicities of these proteins are weak. However, the clinical effects of HLA-C and -DP donor-specific HLA antibodies (DSHAs) have recently been reevaluated. Methods: Here, we report the case of a retransplant patient with positive flow cytometry crossmatch (FCXM) and high level of HLA-DP DSHA who was desensitized using rituximab, plasmapheresis, and intravenous immunoglobulin. Results: The epitope-based antibody reactivity was identified that the positive B-cell FCXM in our patient was attributable to the specific epitope. The patient underwent a successful retransplantation and has continued to do well for 10 month after KT. Conclusion: If an HLA-DP DSHA is present, it is important to detect any mismatched HLA-DP epitope pretransplantation and to monitor HLA-DP levels carefully. According to previous reports, anti-HLA-DP DSHA can induce ABMR soon after transplantation, but such ABMR can be prevented by pretransplantation desensitization and careful monitoring of DSHA levels. PMID:27512872

  3. MDMA DECREASES THE EFFECTS OF SIMULATED SOCIAL REJECTION

    OpenAIRE

    Frye, Charles G.; Wardle, Margaret C; Norman, Greg J.; de Wit, Harriet

    2013-01-01

    3-4-methylenedioxymethamphetamine (MDMA) increases self-reported positive social feelings and decreases the ability to detect social threat in faces, but its effects on experiences of social acceptance and rejection have not been determined. We examined how an acute dose of MDMA affects subjective and autonomic responses to simulated social acceptance and rejection. We predicted that MDMA would decrease subjective responses to rejection. On an exploratory basis, we also examined the effect of...

  4. Regulatory Allospecific T Cell Clones Abrogate Chronic Allograft Rejection

    OpenAIRE

    Waaga-Gasser, Ana Maria; Grimm, Martin R.; Lutz, Jens; Lange, Volkmar; Lenhard, Susanne M.; Aviles, Beatriz; Kist-van Holthe, Joana E; Lebedeva, Tatiana; Samsonov, Dimitry; Meyer, Detlef; Hancock, Wayne W.; Heemann, Uwe; Gasser, Martin; Chandraker, Anil

    2009-01-01

    True alloantigen-specific tolerance is the ultimate goal of solid organ transplantation, eliminating the need for long-term immunosuppression. Recent evidence suggests that Th1-derived cytokines are associated with rejection and Th2-derived cytokines with long-term allograft survival, but the roles of these subsets in rejection and tolerance are incompletely understood. Here, we analyzed the functional and regulatory capacities of T cell clones derived from tolerant and rejecting rats (Wistar...

  5. Rejection of Organic Micropollutants by Clean and Fouled Nanofiltration Membranes

    OpenAIRE

    Lifang Zhu

    2015-01-01

    The rejection of organic micropollutants, including three polycyclic aromatic hydrocarbons (PAHs) and three phthalic acid esters (PAEs), by clean and fouled nanofiltration membranes was investigated in the present study. The rejection of organic micropollutants by clean NF90 membranes varied from 87.9 to more than 99.9%, while that of NF270 membranes ranged from 32.1 to 92.3%. Clear time-dependence was observed for the rejection of hydrophobic micropollutants, which was attributed to the adso...

  6. The private rejection of unfair offers and emotional commitment

    OpenAIRE

    Yamagishi, Toshio; Horita, Yutaka; Takagishi, Haruto; Shinada, Mizuho; Tanida, Shigehito; Cook, Karen S.

    2009-01-01

    In a series of experiments, we demonstrate that certain players of an economic game reject unfair offers even when this behavior increases rather than decreases inequity. A substantial proportion (30–40%, compared with 60–70% in the standard ultimatum game) of those who responded rejected unfair offers even when rejection reduced only their own earnings to 0, while not affecting the earnings of the person who proposed the unfair split (in an impunity game). Furthermore, even when the responde...

  7. Impact of Early Blood Transfusion After Kidney Transplantation on the Incidence of Donor-Specific Anti-HLA Antibodies.

    Science.gov (United States)

    Ferrandiz, I; Congy-Jolivet, N; Del Bello, A; Debiol, B; Trébern-Launay, K; Esposito, L; Milongo, D; Dörr, G; Rostaing, L; Kamar, N

    2016-09-01

    Little is known about the impact of posttransplant blood transfusion on the sensitization of anti-HLA antibodies and the formation of donor-specific antibodies (DSAs). The aims of our study were to determine the 1-year incidence of DSAs (assessed using a solid-phase assay) and antibody-mediated rejection (AMR) in kidney transplant patients who had or had not received a blood transfusion during the first year after transplantation. Included were 390 non-HLA-sensitized patients who had received an ABO-compatible kidney transplant and had not previously or simultaneously received a nonkidney transplant. Overall, 64% of patients received a red blood cell transfusion within the first year after transplantation, most within the first month. The overall 1-year incidence of DSAs was significantly higher in patients that had undergone transfusion (7.2% vs. 0.7% in patients with no transfusion, p transfusion group (n = 15, 6%) compared with the nontransfusion group (n = 2, 1.4%; p = 0.04). Blood transfusion was an independent predictive factor for de novo DSA formation but not for AMR. Patients who had a transfusion and developed DSAs were more often treated with cyclosporin A (n = 10, 55.5%) rather than tacrolimus (n = 45, 19.4%; p = 0.0001). In conclusion, early posttransplant blood transfusion may increase immunological risk, especially in underimmunosuppressed patients.

  8. Community rejection following sexual assault as ‘forced migration’

    OpenAIRE

    AJ Morgen

    2013-01-01

    When women are banished from their communities following sexual assault, this rejection should be considered an act of forced migration by the administrators of truth commission reparations programmes.

  9. Cytomegalovirus and chronic allograft rejection in liver transplantation

    Institute of Scientific and Technical Information of China (English)

    Liang-Hui Gao; Shu-Sen Zheng

    2004-01-01

    Cytomegalovirus (CMV) remains one of the most frequent viral infections and the most common cause of death after liver transplantation (LT). Chronic allograft liver rejection remains the major obstacle to long-term allograft survival and CMV infection is one of the suggested risk factors for chronic allograft rejection. The precise relationship between cytomegalovirus and chronic rejection remains uncertain.This review addresses the morbidity of cytomegalovirus infection and the risk factors associated with it, the relationship between cytomegalovirus and chronic allograft liver rejection and the potential mechanisms of it.

  10. Recipient Myd88 Deficiency Promotes Spontaneous Resolution of Kidney Allograft Rejection.

    Science.gov (United States)

    Lerret, Nadine M; Li, Ting; Wang, Jiao-Jing; Kang, Hee-Kap; Wang, Sheng; Wang, Xueqiong; Jie, Chunfa; Kanwar, Yashpal S; Abecassis, Michael M; Luo, Xunrong; Zhang, Zheng

    2015-11-01

    The myeloid differentiation protein 88 (MyD88) adapter protein is an important mediator of kidney allograft rejection, yet the precise role of MyD88 signaling in directing the host immune response toward the development of kidney allograft rejection remains unclear. Using a stringent mouse model of allogeneic kidney transplantation, we demonstrated that acute allograft rejection occurred equally in MyD88-sufficient (wild-type [WT]) and MyD88(-/-) recipients. However, MyD88 deficiency resulted in spontaneous diminution of graft infiltrating effector cells, including CD11b(-)Gr-1(+) cells and activated CD8 T cells, as well as subsequent restoration of near-normal renal graft function, leading to long-term kidney allograft acceptance. Compared with T cells from WT recipients, T cells from MyD88(-/-) recipients failed to mount a robust recall response upon donor antigen restimulation in mixed lymphocyte cultures ex vivo. Notably, exogenous IL-6 restored the proliferation rate of T cells, particularly CD8 T cells, from MyD88(-/-) recipients to the proliferation rate of cells from WT recipients. Furthermore, MyD88(-/-) T cells exhibited diminished expression of chemokine receptors, specifically CCR4 and CXCR3, and the impaired ability to accumulate in the kidney allografts despite an otherwise MyD88-sufficient environment. These results provide a mechanism linking the lack of intrinsic MyD88 signaling in T cells to the effective control of the rejection response that results in spontaneous resolution of acute rejection and long-term graft protection.

  11. Antitumor vaccines, immunotherapy and the immunological constant of rejection.

    Science.gov (United States)

    Wang, Ena; Monaco, Alessandro; Monsurró, Vladia; Sabatino, Marianna; Pos, Zoltan; Uccellini, Lorenzo; Wang, Jeanne; Worschech, Andrea; Stroncek, David F; Marincola, Francesco M

    2009-05-01

    Anticancer vaccines have not matched the clinical expectations projected from their ability to induce consistently systemic anticancer T-cell responses. Thus, a dichotomy is observed between the immunological and clinical endpoints of anticancer immunization. Anticancer vaccines have clearly demonstrated that highly specific T-cell responses can be induced that can recognize autologous cancer antigens in patients with cancer. This ability is an outstanding achievement of modern biotechnology, yielding one of the most specific types of potential anticancer reagents. However, systemic, vaccine-induced anticancer responses exemplify a broader immunological paradox: cytotoxic T-cells can coexist within the same organism with their target cells not only in the context of cancer, but also in the context of chronic infections, well-controlled allo-transplant reactions and autoimmunity. According to this view, anticancer immune responses are a facet of a tissue-specific autoimmune phenomenon specific for cancer tissue that may or may not result in the successful immune-destruction of target cells, depending on an assortment of genetic factors related to the background of the host or evolving phenotypes of a heterogeneous cancer environment. This feature article summarizes the current understanding of the mechanisms leading to tumor rejection in humans as well as in experimental models, in the context of the broader immunological phenomenon leading to tissue-specific destruction. Anticancer vaccines that may not induce clinically significant anticancer responses independently could function as a unique tool to enhance the specificity of the response of the host against cancer, provided that strategies are implemented to amplify the immune reaction initiated by vaccine-induced antibodies and/or T-cells.

  12. Monoclonal antibodies.

    Science.gov (United States)

    2009-01-01

    The ability to produce and exploit monoclonal antibodies (mAbs) has revolutionized many areas of biological sciences. The unique property of an mAb is that it is a single species of immunoglobulin (IG) molecule. This means that the specificity of the interaction of the paratopes on the IG, with the epitopes on an antigenic target, is the same on every molecule. This property can be used to great benefit in immunoassays to provide tests of defined specificity and sensitivity, which improve the possibilities of standardization. The performance of assays can often be determined relating the actual weight of antibody (hence the number of molecules) to the activity. Often the production of an mAb against a specific epitope is the only way that biological entities can be differentiated. This chapter outlines the areas involving the development of assays based on mAbs. The problems involved address include the physical aspects of mAbs and how they may affect assay design and also the implications of results based on monospecific reagents. Often these are not fully understood, leading to assays that are less than satisfactory, which does not justify the relatively high cost of preparing and screening of mAbs. There are many textbooks and reviews dealing with the preparation of mAbs, the principles involved, and various purification and manipulative methods for the preparation of fragments and conjugation. There has been little general information attempting to summarize the best approaches to assay design using mAbs. Much time can be wasted through bad planning, and this is particularly relevant to mAbs. A proper understanding of some basic principles is essential. It is beyond the scope of this chapter to discuss all aspects, but major areas are highlighted. PMID:19219589

  13. Adolescent social rejection alters pain processing in a CB1 receptor dependent manner.

    Science.gov (United States)

    Schneider, Peggy; Pätz, Monique; Spanagel, Rainer; Schneider, Miriam

    2016-07-01

    Experiences of social rejection represent a major source of distress and in particular peer rejection during adolescence has been implicated in various psychiatric disorders. Moreover, experimentally induced acute social rejection alters pain perception in humans, implicating overlapping neurocircuits for social and physical pains. We recently demonstrated that rearing of adolescent Wistar rats with inadequate, less playful play partners (Fischer 344) persistently decreases pain sensitivity, although the detailed mechanisms mediating the aversiveness during the social encounter remained unsettled. With the present study we examined the behavioral performance during acute interaction of female adolescent Wistar rats with either age-matched same-strain partners or rats from the Fischer 344 strain. We here identify the low responsiveness upon playful attacks, which appears to be characteristic for social play in the Fischer 344 strain, as one of the main aversive components for adolescent Wistar animals during cross-strain encounters, which subsequently diminishes thermal pain reactivity. A detailed behavioral analysis further revealed increased ultrasonic vocalization at 50kHz and an increased frequency of playful attacks for adolescent Wistar animals paired with a Fischer 344 rat compared to same-strain control pairs. Finally, an acute injection of a subthreshold dose of the cannabinoid type 1 receptor inverse agonist/antagonist SR141716 before the social encounter abolished enhanced play-soliciting behavior in Wistar/Fischer 344 pairs as well as the behavioral consequences of the rejection experience in adolescent Wistar rats, further emphasizing an important modulatory role of the endocannabinoid system in mediating the effects of social behavior and social pain. PMID:27157075

  14. Efficacy of total lymphoid irradiation for chronic allograft rejection following bilateral lung transplantation

    International Nuclear Information System (INIS)

    Purpose: To assess the safety and efficacy of total lymphoid irradiation (TLI) in patients experiencing chronic rejection following bilateral lung transplantation (BLT). Patients and Materials: Eleven patients received TLI for chronic allograft rejection (bronchiolitis obliterans syndrome) refractory to conventional treatment modalities. Radiation therapy (RT) was prescribed as 8 Gy delivered in 10 0.8-Gy fractions, 2 fractions/week, via mantle, paraaortic, and inverted-Y fields. Serial pre- and post-RT pulmonary function values, complete blood counts, and immunosuppressive augmentation requirements [use of methylprednisolone, murine anti-human mature T-cell monoclonal antibody (OKT3), polyclonal antithymocyte globulin (ATG), and tacrolimus] were monitored. Results: In the 3 months preceding TLI, the average decrease in forced expiratory volume in 1 s (FEV1) was 34% (range 0-75%) and the median number of immunosuppression augmentations was 3 (range 0-5). Only 4 of 11 patients completed all 10 TLI treatment fractions. Reasons for discontinuation included progressive pulmonary decline (four patients), worsening pulmonary infection (two patients), and persistent thrombocytopenia (one patient). Seven of the 11 patients failed within 8 weeks of treatment cessation. One patient had unabated rejection and received bilateral living related-donor transplants; he is alive and well. Six patients died. Two of these deaths were due to pulmonary infection from organisms isolated prior to the start of RT; the other four deaths were from progressive pulmonary decline. The four remaining patients had durable positive responses to TLI (mean follow-up of 47 weeks; range 24-72). Comparing the 3 months preceding RT to the 3 months following treatment, these four patients had improvements in average FEV1 (40% decline vs. 1% improvement) and fewer median number of immunosuppressive augmentations (3.5 vs. 0). None of these patients has developed lymphoproliferative disease or has died

  15. 25 CFR 163.18 - Acceptance and rejection of bids.

    Science.gov (United States)

    2010-04-01

    ... bids; or (2) Acceptance of the offer of another bidder who, at bid opening, makes written request that... 25 Indians 1 2010-04-01 2010-04-01 false Acceptance and rejection of bids. 163.18 Section 163.18... Forest Management and Operations § 163.18 Acceptance and rejection of bids. (a) The high bid received...

  16. Graft rejection after hematopoietic cell transplantation with nonmyeloablative conditioning

    DEFF Research Database (Denmark)

    Masmas, T.N.; Petersen, S.L.; Madsen, H.O.;

    2008-01-01

    -dose fludarabine and total body irradiation (TBI). The association of pretransplantation risk factors with rejection and the effect of chimerism and graft-versus-host disease on rejection were analyzed. Overall survival (OS) and progression free survival (PFS) were compared between patients with and without...

  17. 48 CFR 1419.505 - Rejecting Small Business Administration recommendations.

    Science.gov (United States)

    2010-10-01

    ... Rejecting Small Business Administration recommendations. (a) A written justification in support of the CO's... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Rejecting Small Business Administration recommendations. 1419.505 Section 1419.505 Federal Acquisition Regulations System DEPARTMENT...

  18. 48 CFR 19.505 - Rejecting Small Business Administration recommendations.

    Science.gov (United States)

    2010-10-01

    ... Small Business Administration recommendations. (a) If the contracting officer rejects a recommendation... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Rejecting Small Business Administration recommendations. 19.505 Section 19.505 Federal Acquisition Regulations System FEDERAL...

  19. 48 CFR 219.505 - Rejecting Small Business Administration recommendations.

    Science.gov (United States)

    2010-10-01

    ...-Asides for Small Business 219.505 Rejecting Small Business Administration recommendations. (b) The... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Rejecting Small Business Administration recommendations. 219.505 Section 219.505 Federal Acquisition Regulations System...

  20. 48 CFR 2919.505 - Rejecting Small Business Administration recommendations.

    Science.gov (United States)

    2010-10-01

    ... Small Business 2919.505 Rejecting Small Business Administration recommendations. When the SBA... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Rejecting Small Business Administration recommendations. 2919.505 Section 2919.505 Federal Acquisition Regulations System DEPARTMENT...

  1. 48 CFR 14.404-2 - Rejection of individual bids.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Rejection of individual... of individual bids. (a) Any bid that fails to conform to the essential requirements of the invitation... total price of the bid, but the prices for individual line items as well. (g) Any bid may be rejected...

  2. 48 CFR 814.404-2 - Rejection of individual bids.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Rejection of individual... Rejection of individual bids. (a) When a contracting officer finds a bid that is being considered for an... nonresponsive an individual bid that is not in compliance with the Government's bid acceptance time,...

  3. Family Rejection Triples Risk for Suicide Attempts by Transgender People

    Science.gov (United States)

    ... contact with their child; there were incidents of domestic violence; children cut off communication; or parents or siblings stopped communicating with the person. In the case of "high" level rejection, the ... study found. A high level of family rejection was tied to a two and a ...

  4. Subclinical Rejection in Renal Transplantation: Reappraised.

    Science.gov (United States)

    Mehta, Rajil; Sood, Puneet; Hariharan, Sundaram

    2016-08-01

    Short-term outcomes in renal transplantation have improved significantly in the past few years. However, the improvement in long-term outcomes has been modest. The reasons for graft failure beyond the first year of transplantation have been attributed to several different factors. We believe that subclinical rejection (SCR) may be 1 of the factors that contribute to graft loss in the long run. We also believe that there are data to suggest that SCR leads to progressive fibrosis and loss of graft function. This has been demonstrated even in patients who have mild degrees of subclinical inflammation. This review outlines the major studies that have been published on this important topic. It also outlines potential risk factors for the development of SCR. The current approach and diagnostic methods are discussed as well as their pros and cons. Newer noninvasive methods of diagnosis as well as molecular diagnostics and their merits and shortcomings are also discussed in some depth. Thus, the proposed state of the art review on SCR will create a renewed interest at all levels including transplant clinicians, transplant researchers, pharmaceutical industries as well as regulatory organizations. PMID:26985747

  5. Ferrite grade iron oxides from ore rejects

    Indian Academy of Sciences (India)

    K S Rane; V M S Verenkar; P Y Sawant

    2001-06-01

    Iron oxyhydroxides and hydroxides were synthesized from chemically beneficiated high SiO2/Al2O3 low-grade iron ore (57.49% Fe2O3) rejects and heated to get iron oxides of 96–99.73% purity. The infrared band positions, isothermal weight loss and thermogravimetric and chemical analysis established the chemical formulas of iron-oxyhydroxides as -FeOOH.0.3H2O; -FeOOH.0.2H2O and amorphous FeOOH. The thermal products of all these were -Fe2O3 excepting that of -FeOOH.0.3H2O which gave mainly -Fe2O3 and some admixture of -Fe2O3. The hydrazinated iron hydroxides and oxyhydroxides, on the other hand, decomposed autocatalytically to mainly -Fe2O3. Hydrazine method modifies the thermal decomposition path of the hydroxides. The saturation magnetization, s, values were found to be in the range 60–71 emu g–1 which are close to the reported values for -Fe2O3. Mechanism of the -Fe2O3 formation by hydrazine method is discussed.

  6. Alpha Background Rejection in Bolometer Detectors

    Science.gov (United States)

    Deporzio, Nicholas; Cuore Collaboration

    This study presents the modification of bolometer detectors used in particle searches to veto or otherwise reject alpha radiation background and the statistical advantages of doing so. Several techniques are presented in detail - plastic film scintillator vetoes, metallic film ionization vetoes, and Cherenkov radiation vetoes. Plastic scintillator films are cooled to bolometer temperatures and bombarded with 1.4MeV to 6.0MeV alpha particles representative of documented detector background. Quantum dot based liquid scintillator is similarly bombarded to produce a background induced scintillation light. Photomultipliers detect this scintillation light and produce a veto signal. Layered metallic films of a primary metal, dielectric, and secondary metal, such as gold-polyethylene-gold films, are cooled to milli-kelvin temperatures and biased to produce a current signal veto when incident 1.4MeV to 6.0MeV alpha particles ionize conduction paths through the film. Calibration of veto signal to background energy is presented. These findings are extrapolated to quantify the statistical impact of such modifications to bolometer searches. Effects of these techniques on experiment duration and signal-background ratio are discussed.

  7. Solar gains and thermal rejects by ventilation

    International Nuclear Information System (INIS)

    Data recorded between September 1983 and February 1985 were analyzed in detail and the main results are as follows: • Solar radiation covers a large fraction of the daily heat load : in local climatic conditions, between October and June, solar energy provided for nearly 40 % of the heat load of the greenhouse. This amount represents 32 % of the incident radiation. • Thermal excesses that were ventilated during overheating periods (Tint > 24 °C) represent 37 % of the incident solar energy. However, due to the seasonal phase differences between the thermal need and the incident solar power, only half of these rejects could potentially be saved by a short term storage system. • A method was developed for determining the monthy net auxiliary consumption of the greenhouse. Solar gains were evaluated by means of a monthly utilization factor (ratio of the solar energy used divided by the absorbed solar energy in the greenhouse). This factor has been experimentally fitted to a function of the gain load ratio (ratio of absorbed solar energy divided by the daytime heat load). The above representation appears to be valid for any type of climate or greenhouse. • The model also takes into account the effect of wind and radiative heat losses to the sky and calculates the net auxiliary requirements within less than 10%. (author)

  8. Acute Rejection after Human Renal Transplantation

    Directory of Open Access Journals (Sweden)

    Ana Roussoulières

    2007-01-01

    Full Text Available Genes involved in acute rejection (AR after organ transplantation remain to be further elucidated. In a previous work we have demonstrated the under-expression of VE-Cadherin by endothelial cells (EC in AR following murine and human heart transplantation. Serial sections from 15 human kidney Banff-graded transplant biopsies were examined for the presence of VE-Cadherin and CD34 staining by immunohistochemistry (no AR (n=5, AR grade IA (n=5, or AR grade IIA (n=5. Quantification of peritubular EC staining were evaluated and results were expressed by the percentage of stained cells per surface analysed. There was no difference in CD34 staining between the 3 groups. VE-Cadherin expression was significantly reduced in AR Grade IIA when compared to no AR (P=.01 and to AR grade IA (P=.02. This study demonstrates a reduced VE-Cadherin expression by EC in AR after renal transplantation. The down-regulation of VE-Cadherin may strongly participate in human AR.

  9. Background Assay and Rejection in DRIFT

    CERN Document Server

    Brack, Jeff; Dorofeev, Alexei; Ezeribe, Anthony; Gauvreau, Jean-Luc; Gold, Michael; Harton, John; Lafler, Randy; Lauer, Robert; Lee, Eric R; Loomba, Dinesh; Matthews, John; Miller, Eric H; Monte, Alissa; Murphy, Alex; Paling, Sean; Phan, Nguyen; Sadler, Steve; Scarff, Andrew; Snowden-Ifft, Daniel; Spooner, Neil; Telfer, Sam; Walker, Daniel; Williams, Matt; Yuriev, Leonid

    2014-01-01

    The DRIFT-IId dark matter detector is a m$^3$-scale low-pressure TPC with directional sensitivity to WIMP-induced nuclear recoils. Its primary backgrounds were due to alpha decays from contamination on the central cathode. Efforts to reduce these backgrounds led to replacing the 20 \\mu m wire central cathode with one constructed from 0.9 \\mu m aluminized mylar, which is almost totally transparent to alpha particles. Detailed modeling of the nature and origin of the remaining backgrounds led to an in-situ, ppt-sensitive assay of alpha decay backgrounds from the central cathode. This led to further improvements in the thin-film cathode resulting in over 2 orders of magnitude reduction in backgrounds compared to the wire cathode. Finally, the addition of O$_2$ to CS$_2$ gas was found to produce multiple species of electronegative charge carriers, providing a method to determine the absolute position of nuclear recoils and reject all known remaining backgrounds while retaining a high efficiency for nuclear recoil...

  10. [Antinuclear antibodies].

    Science.gov (United States)

    Cabiedes, Javier; Núñez-Álvarez, Carlos A

    2010-01-01

    Anti-nuclear antibodies (ANA) are immunoglobulin directed against autologous cell nuclear and cytoplasmic components. Besides the autoimmune ANA there are other ANA that can be detected in circulation, like natural and infectious ANA. Because of its high sensibility, detection of the ANA must be done by indirect immunofluorescence (IIF) as screening test and all of those positive samples are convenient to confirm its specificity by ELISA, western blot or other techniques. Positive ANA detected by IIF must be evaluated taking in to account the pattern and titer. The following recommended step is the specificity characterization (reactivity against extractable nuclear antigens [ENA], dsDNA, etc.) which is useful for the diagnosis and follow up of patients with autoimmune diseases, and by such reasoning, its detection must be performed in an orderly and reasonable way using guides or strategies focused to the good use and interpretation of the autoantibodies. The objective of this review is to present a compilation of the literature and our experience in the detection and study of the ANA.

  11. Solar dynamic heat rejection technology. Task 1: System concept development

    Science.gov (United States)

    Gustafson, Eric; Carlson, Albert W.

    1987-01-01

    The results are presented of a concept development study of heat rejection systems for Space Station solar dynamic power systems. The heat rejection concepts are based on recent developments in high thermal transport capacity heat pipe radiators. The thermal performance and weights of each of the heat rejection subsystems is addressed in detail, and critical technologies which require development tests and evaluation for successful demonstration are assessed and identified. Baseline and several alternate heat rejection system configurations and optimum designs are developed for both Brayton and Rankine cycles. The thermal performance, mass properties, assembly requirements, reliability, maintenance requirements and life cycle cost are determined for each configuration. A specific design was then selected for each configuration which represents an optimum design for that configuration. The final recommendations of heat rejection system configuration for either the Brayton or Rankine cycles depend on the priorities established for the evaluation criteria.

  12. Rejection of micropollutants by clean and fouled forward osmosis membrane.

    Science.gov (United States)

    Valladares Linares, Rodrigo; Yangali-Quintanilla, Victor; Li, Zhenyu; Amy, Gary

    2011-12-15

    As forward osmosis (FO) gains attention as an efficient technology to improve wastewater reclamation processes, it is fundamental to determine the influence of fouling in the rejection of emerging contaminants (micropollutants). This study focuses on the rejection of 13 selected micropollutants, spiked in a secondary wastewater effluent, by a FO membrane, using Red Sea water as draw solution (DS), differentiating the effects on the rejection caused by a clean and fouled membrane. The resulting effluent was then desalinated at low pressure with a reverse osmosis (RO) membrane, to produce a high quality permeate and determine the rejection with a coupled forward osmosis - low pressure reverse osmosis (FO-LPRO) system. When considering only FO with a clean membrane, the rejection of the hydrophilic neutral compounds was between 48.6% and 84.7%, for the hydrophobic neutrals the rejection ranged from 40.0% to 87.5%, and for the ionic compounds the rejections were between 92.9% and 96.5%. With a fouled membrane, the rejections were between 44.6% and 95.2%, 48.7%-91.5% and 96.9%-98.6%, respectively. These results suggest that, except for the hydrophilic neutral compounds, the rejection of the micropollutants is increased by the presence of a fouling layer, possibly due to the higher hydrophilicity of the FO fouled membrane compared to the clean one, the increased adsorption capacity of hydrophilic compounds and reduced mass transport capacity, membrane swelling, and the higher negative charge of the membrane surface, related to the foulants composition, mainly NOM acids (carboxylic radicals) and polysaccharides or polysaccharide-like substances. However, when coupled with RO, the rejections in both cases increased above 96%. The coupled FO-LPRO system was an effective double barrier against the selected micropollutants. PMID:22055122

  13. Rejection of micropollutants by clean and fouled forward osmosis membrane

    KAUST Repository

    Valladares Linares, Rodrigo

    2011-12-01

    As forward osmosis (FO) gains attention as an efficient technology to improve wastewater reclamation processes, it is fundamental to determine the influence of fouling in the rejection of emerging contaminants (micropollutants). This study focuses on the rejection of 13 selected micropollutants, spiked in a secondary wastewater effluent, by a FO membrane, using Red Sea water as draw solution (DS), differentiating the effects on the rejection caused by a clean and fouled membrane. The resulting effluent was then desalinated at low pressure with a reverse osmosis (RO) membrane, to produce a high quality permeate and determine the rejection with a coupled forward osmosis - low pressure reverse osmosis (FO-LPRO) system. When considering only FO with a clean membrane, the rejection of the hydrophilic neutral compounds was between 48.6% and 84.7%, for the hydrophobic neutrals the rejection ranged from 40.0% to 87.5%, and for the ionic compounds the rejections were between 92.9% and 96.5%. With a fouled membrane, the rejections were between 44.6% and 95.2%, 48.7%-91.5% and 96.9%-98.6%, respectively. These results suggest that, except for the hydrophilic neutral compounds, the rejection of the micropollutants is increased by the presence of a fouling layer, possibly due to the higher hydrophilicity of the FO fouled membrane compared to the clean one, the increased adsorption capacity of hydrophilic compounds and reduced mass transport capacity, membrane swelling, and the higher negative charge of the membrane surface, related to the foulants composition, mainly NOM acids (carboxylic radicals) and polysaccharides or polysaccharide-like substances. However, when coupled with RO, the rejections in both cases increased above 96%. The coupled FO-LPRO system was an effective double barrier against the selected micropollutants. © 2011 Elsevier Ltd.

  14. Role of TDTH and Tc populations in organ graft rejection. I. Functional analysis of graft-infiltrating T cells

    Energy Technology Data Exchange (ETDEWEB)

    Stepkowski, S.M.; Duncan, W.R.

    1986-10-01

    To analyze the role of T cell subpopulations in the rejection of organ allografts, we developed a new model for obtaining large numbers of graft infiltrating cells (GICs). We isolated W3/25+ Th/DTH and OX8+ Ts/c from vascularized, irradiated rat spleen allografts. W3/25+ GICs obtained from spleen allografts transplanted to normal recipients were highly effective in eliciting cardiac allograft rejection when transferred to sublethally irradiated recipients, however, the OX8+ subset was incapable of eliciting rejection. On the other hand, when OX8+ GICs were obtained from spleen allografts transplanted to previously immunized recipients, they were as efficient as the W3/25+ Th/DTH subset in eliciting cardiac allograft destruction. These results indicate that the W3/25+, OX8- T cell is required for the rejection of primary organ allografts, but that the rejection of a secondary allograft by an immune recipient may be mediated, independently, by both W3/25+ and OX8+ cells.

  15. Rejected by Peers--Attracted to Antisocial Media Content: Rejection-Based Anger Impairs Moral Judgment among Adolescents

    Science.gov (United States)

    Plaisier, Xanthe S.; Konijn, Elly A.

    2013-01-01

    Adolescence is an important developmental stage during which both peers and the media have a strong influence. Both peer rejection and the use of morally adverse media are associated with negative developmental outcomes. This study examines processes by which peer rejection might drive adolescents to select antisocial media content by tying…

  16. Neuropeptide-mediated regulation of hapten-specific IgE responses in mice. I. Substance P-mediated isotype-specific suppression of BPO-specific IgE antibody-forming cell responses induced in vivo and in vitro.

    Science.gov (United States)

    Carucci, J A; Auci, D L; Herrick, C A; Durkin, H G

    1995-01-01

    The ability of substance P (SP) to regulate peak benzyl-penicilloyl (BPO)-specific IgE antibody-forming cell (AFC) responses in vivo and the ability of SP and other neuropeptides to regulate BPO-specific memory IgE AFC responses induced in vitro was determined. SP injected subcutaneously into BPO-keyhole limpet hemocyanin (BPO-KLH)-sensitized mice at the time of peak IgE responses suppressed these responses within 48 h (> 90%). The suppression obtained was IgE isotype-specific, dose-dependent, and transient. When spleen cells from immunized mice were cultured for 5 days with BPO-KLH, peak memory IgE AFC responses were induced in vitro. Inclusion of either SP or vasoactive intestinal peptide (VIP), but not neurotensin, serotonin, somatostatin, or gastrin, in cultures suppressed these responses in isotype-specific, dose-dependent fashion (approximately 70%). SP-, but not VIP-mediated suppression of IgE responses was abrogated by inclusion of anti-IFN gamma culture.

  17. DYNAMICS OF IRIG IN TREATMENT OF HEART TRANSPLANT REJECTIONS

    Directory of Open Access Journals (Sweden)

    A. O. Shevchenko

    2015-01-01

    Full Text Available In cardiac recipients non-invasive monitoring will identify the risk of acute rejection, as well as reduce the number of routine biopsies. The relation between the development of the transplanted heart rejection and the change of elastic properties of common carotid artery has been proved. Aim: to analyze dynamics of iRIG in treatment of graft rejection in heart recipients.Materials and methods. 59 heart recipients were examined: 21 patients (ptswithout rejection, 20 pts – with rejection after 1st biopsy, 15 pts – with rejection after 1st and 2 biopsies, 3 pts – with persistent rejection after all biopsies. iRIG was estimated using empirical equation.Results. Dynamics of iRIG in pts. without rejection according to all biopsies over time was not signifi cantly changed 6280 ± 2143, 6083 ± 2388, 6362 ± 1984 and 6188 ± 3012 cm/sec2 (p = 0.11, p = 0.13, p = 0.17 between the 1st and 2nd, 2nd and 3rd, 3rd and 4th values, respectively. In pts. with rejection iRIG decreased during treatment, but was signifi cantly higher even after successful treatment. In patients with persistent rejection iRIG did not decrease and tended to increase (17 459 ± 9702 cm/sec2 on the results of the 1st biopsy to 21 305 ± 10 448 cm/sec2 on the results of the 4th biopsy.Conclusions. In patients with heart transplant iRIG does not change signifi cantly with the time after transplantation. iRIG increases in all types of rejection, followed by its decrease in the course of therapy; in patients with persistent rejection iRIG remains high. Evaluation of iRIG can be used for non-invasive monitoring of patients after heart transplantations (HTx and to identify patients at high risk of transplant rejection.

  18. Acute rejection episodes after kidney transplantation

    Directory of Open Access Journals (Sweden)

    Hamida Fethi

    2009-01-01

    Full Text Available Acute rejection episodes (AREs are a major determinant of renal allograft survival. The incorporation of new immunosuppressive agents explains, at least partially, the improvement seen in the results of transplantation in recent years. The objectives of this study are to analyze the incidence and severity of AREs, their risk factors and their influence on graft and patient survival. We retrospectively studied 280 kidney transplants performed in adults at the Charles Nicolle Hospital, Tunis, between 1986 and 2004. The diagnosis of ARE was based on clinical data and response to treatment. Allograft biopsies were performed in ten cases. The treatment of AREs consisted of pulse methylprednisolone and anti-thymocyte globulin. There were 186 males (66.4% and 94 females (33.6%, and their mean age was 31 ± 8.9 years. Overall, the 280 study patients experienced a total of 113 AREs. Of them, 85 had only one ARE, 28 had two to three and none had more than three AREs. A total of 68 AREs were completely re-versible, 42 were partially reversible while three could not be reversed with treatment. The mean inci-dence of AREs was 40.4%. The incidence was > 45% between 1986 and 1997, decreased to 20.5% between 1998 and 2000 and to 9% between 2001 and 2004. Graft survival rates in patients with and without AREs were respectively 91% and 93% at three years, 82% and 90% at five years and 73% and 83% at 10 years. We found a decrease in the incidence of AREs in recent years in our study patients, and this was related to the introduction of sensitized cross-match and the newer immunosuppressive agents, particularly MMF. Additionally, AREs had a deleterious impact on late graft survival in our study population.

  19. Immunologic basis of graft rejection and tolerance following transplantation of liver or other solid organs.

    Science.gov (United States)

    Sánchez-Fueyo, Alberto; Strom, Terry B

    2011-01-01

    Transplantation of organs between genetically different individuals of the same species causes a T cell-mediated immune response that, if left unchecked, results in rejection and graft destruction. The potency of the alloimmune response is determined by the antigenic disparity that usually exists between donors and recipients and by intragraft expression of proinflammatory cytokines in the early period after transplantation. Studies in animal models have identified many molecules that, when targeted, inhibit T-cell activation. In addition, some of these studies have shown that certain immunologic interventions induce transplantation tolerance, a state in which the allograft is specifically accepted without the need for chronic immunosuppression. Tolerance is an important aspect of liver transplantation, because livers have a unique microenvironment that promotes tolerance rather than immunity. In contrast to the progress achieved in inducing tolerance in animal models, patients who receive transplanted organs still require nonspecific immunosuppressant drugs. The development of calcineurin inhibitors has reduced the acute rejection rate and improved short-term, but not long-term, graft survival. However, long-term use of immunosuppressive drugs leads to nephrotoxicity and metabolic disorders, as well as manifestations of overimmunosuppression such as opportunistic infections and cancers. The status of pharmacologic immunosuppression in the clinic is therefore not ideal. We review recently developed therapeutic strategies to promote tolerance to transplanted livers and other organs and diagnostic tools that might be used to identify patients most likely to accept or reject allografts.

  20. Studies of CTLA4Ig in acute rejection of pancreas transplantation in rats

    Institute of Scientific and Technical Information of China (English)

    Junbo Yu; Zekuan Xu; Shuguang Han; Yi Miao

    2006-01-01

    Objective: To investigate the protective effect of CTLA4Ig in rejection of pancreaticoduodenal transplantation model of rat. Methods: Pancreaticoduodenal transplantion models were established from the donor F344 rats to the Lewis recipients. The models were divided into 2 groups: Group A and B with 12 rats in each group.2 days after transplantation, reciepients in group A were treated with i.p. injection of sailine, and those in group B CTLA4I were injected(200 μg). On day 1,4,7,10after transplantation, the grafts were harvested for histopathological examination. On day 4 after transplantation, the CD4+CD25+Tcells in the grafts were detected by Flow Cytometry. Results: Compared with group A: the degree of the rejection of grafts in group B was lower. The number of CD4+CD25+ T cells of graft was (7.91±1.26)% in group A and (13.81±1.71)% in group B, which had significant difference(P<0.01). Conclusion: CTLA4Ig could inhibit T cell costimulatory pathway, prevent acute rejection, which might be mediated by increasing the number of CD4+CD25+ regulatory T cells.

  1. Chronic Rejection in Human Vascularized Composite Allotransplantation (Hand and Face Recipients): An Update.

    Science.gov (United States)

    Kanitakis, Jean; Petruzzo, Palmina; Badet, Lionel; Gazarian, Aram; Thaunat, Olivier; Testelin, Sylvie; Devauchelle, Bernard; Dubernard, Jean-Michel; Morelon, Emmanuel

    2016-10-01

    Vascularized composite tissue allografts (VCA) have become a viable option to restore severely damaged parts of the body that cannot be repaired with conventional surgical techniques. Acute rejection develops frequently in the early postgraft period both in human and experimental VCA, but the possibility of human VCA to undergo chronic rejection (CR) remained initially unknown. The experience gained over the years shows that, similar to solid organ transplants (SOT), human VCA can also develop CR. Chronic rejection is clinically mostly apparent on the skin and targets preferentially skin and deep vessels, leading, as in SOT, to graft vasculopathy and often to graft loss. Dermal sclerosis and adnexal atrophy are additional features of CR. The pathogenetic immune mechanisms involved (cell-mediated versus humoral) remain incompletely known. The changes of CR can be detected with skin and deep tissue biopsies. Modern in vivo imaging tools can detect vascular narrowing and have the advantage of being noninvasive. However, the diagnosis and treatment of CR remain challenging, as several important questions remain to be answered: a more accurate definition of CR in VCA is needed to establish criteria allowing an accurate and early diagnosis. The pathogenetic mechanisms of CR need to be better understood to allow more efficacious treatment. Favoring/triggering factors of CR need to be better known so that they can be avoided. As in SOT, there is a need for efficient tolerance-inducing protocols that will favor graft acceptance and (ideally) circumvent the necessity of lifelong immunosuppression. PMID:27163543

  2. Separate neural representations for physical pain and social rejection.

    Science.gov (United States)

    Woo, Choong-Wan; Koban, Leonie; Kross, Ethan; Lindquist, Martin A; Banich, Marie T; Ruzic, Luka; Andrews-Hanna, Jessica R; Wager, Tor D

    2014-01-01

    Current theories suggest that physical pain and social rejection share common neural mechanisms, largely by virtue of overlapping functional magnetic resonance imaging (fMRI) activity. Here we challenge this notion by identifying distinct multivariate fMRI patterns unique to pain and rejection. Sixty participants experience painful heat and warmth and view photos of ex-partners and friends on separate trials. FMRI pattern classifiers discriminate pain and rejection from their respective control conditions in out-of-sample individuals with 92% and 80% accuracy. The rejection classifier performs at chance on pain, and vice versa. Pain- and rejection-related representations are uncorrelated within regions thought to encode pain affect (for example, dorsal anterior cingulate) and show distinct functional connectivity with other regions in a separate resting-state data set (N = 91). These findings demonstrate that separate representations underlie pain and rejection despite common fMRI activity at the gross anatomical level. Rather than co-opting pain circuitry, rejection involves distinct affective representations in humans.

  3. Separate neural representations for physical pain and social rejection.

    Science.gov (United States)

    Woo, Choong-Wan; Koban, Leonie; Kross, Ethan; Lindquist, Martin A; Banich, Marie T; Ruzic, Luka; Andrews-Hanna, Jessica R; Wager, Tor D

    2014-01-01

    Current theories suggest that physical pain and social rejection share common neural mechanisms, largely by virtue of overlapping functional magnetic resonance imaging (fMRI) activity. Here we challenge this notion by identifying distinct multivariate fMRI patterns unique to pain and rejection. Sixty participants experience painful heat and warmth and view photos of ex-partners and friends on separate trials. FMRI pattern classifiers discriminate pain and rejection from their respective control conditions in out-of-sample individuals with 92% and 80% accuracy. The rejection classifier performs at chance on pain, and vice versa. Pain- and rejection-related representations are uncorrelated within regions thought to encode pain affect (for example, dorsal anterior cingulate) and show distinct functional connectivity with other regions in a separate resting-state data set (N = 91). These findings demonstrate that separate representations underlie pain and rejection despite common fMRI activity at the gross anatomical level. Rather than co-opting pain circuitry, rejection involves distinct affective representations in humans. PMID:25400102

  4. Organ transplant tissue rejection: detection and staging by fluorescence spectroscopy

    Science.gov (United States)

    MacAulay, Calum E.; Whitehead, Peter D.; McManus, Bruce; Zeng, Haishan; Wilson-McManus, Janet; MacKinnon, Nick; Morgan, David C.; Dong, Chunming; Gerla, Paul; Kenyon, Jennifer

    1998-07-01

    Patients receiving heart or other organ transplants usually require some level of anti-rejection drug therapy, most commonly cyclosporine. The rejection status of the organ must be monitored to determine the optimal anti-rejection drug therapy. The current method for monitoring post-transplant rejection status of heart transplant patients consists of taking biopsies from the right ventricle. In this work we have developed a system employing optical and signal-processing techniques that will allow a cardiologist to measure spectral changes associated with tissue rejection using an optical catheter probe. The system employs time gated illumination and detection systems to deal with the dynamic signal acquisition problems associated with in vivo measurements of a beating heart. Spectral data processing software evaluates and processes the data to produce a simple numerical score. Results of measurements made on 100 excised transplanted isograft and allograft rat hearts have demonstrated the ability of the system to detect the presence of rejection and to accurately correlate the spectroscopic results with the ISHLT (International Society for Heart and Lung Transplantation) stage of rejection determined by histopathology. In vivo measurements using a pig transplant model are now in process.

  5. Spontaneous restoration of transplantation tolerance after acute rejection.

    Science.gov (United States)

    Miller, Michelle L; Daniels, Melvin D; Wang, Tongmin; Chen, Jianjun; Young, James; Xu, Jing; Wang, Ying; Yin, Dengping; Vu, Vinh; Husain, Aliya N; Alegre, Maria-Luisa; Chong, Anita S

    2015-01-01

    Transplantation is a cure for end-stage organ failure but, in the absence of pharmacological immunosuppression, allogeneic organs are acutely rejected. Such rejection invariably results in allosensitization and accelerated rejection of secondary donor-matched grafts. Transplantation tolerance can be induced in animals and a subset of humans, and enables long-term acceptance of allografts without maintenance immunosuppression. However, graft rejection can occur long after a state of transplantation tolerance has been acquired. When such an allograft is rejected, it has been assumed that the same rules of allosensitization apply as to non-tolerant hosts and that immunological tolerance is permanently lost. Using a mouse model of cardiac transplantation, we show that when Listeria monocytogenes infection precipitates acute rejection, thus abrogating transplantation tolerance, the donor-specific tolerant state re-emerges, allowing spontaneous acceptance of a donor-matched second transplant. These data demonstrate a setting in which the memory of allograft tolerance dominates over the memory of transplant rejection.

  6. Rejection of Organic Micropollutants by Clean and Fouled Nanofiltration Membranes

    Directory of Open Access Journals (Sweden)

    Lifang Zhu

    2015-01-01

    Full Text Available The rejection of organic micropollutants, including three polycyclic aromatic hydrocarbons (PAHs and three phthalic acid esters (PAEs, by clean and fouled nanofiltration membranes was investigated in the present study. The rejection of organic micropollutants by clean NF90 membranes varied from 87.9 to more than 99.9%, while that of NF270 membranes ranged from 32.1 to 92.3%. Clear time-dependence was observed for the rejection of hydrophobic micropollutants, which was attributed to the adsorption of micropollutants on the membrane. Fouling with humic acid had a negligible influence on the rejection of organic micropollutants by NF90 membranes, while considerable effects were observed with NF270 membranes, which are significantly looser than NF90 membranes. The observed enhancement in the rejection of organic micropollutants by fouled NF270 membranes was attributed to pore blocking, which was a dominating fouling mechanism for loose NF membranes. Changes in the ionic strength (from 10 to 20 mM reduced micropollutant rejection by both fouled NF membranes, especially for the rejection of dimethyl phthalate and diethyl phthalate by NF270 membranes (from 65.8 to 25.0% for dimethyl phthalate and 75.6 to 33.3% for diethyl phthalate.

  7. Adenoviral-mediated localized CTLA-4Ig gene expression induces long-term allograft pancreas survival and donor-specific immune tolerance in rats

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    T cell activation following alloantigen recognition plays a critical role in the development of the rejection in all solid organ, tissue and cell transplantation. A recombinant molecule, cytotoxic T lymphocyte antigen 4 antibody (CTLA-4Ig), is known to induce to T-cell into "anergy" by blocking the costimulatory B7-CD28 interaction. Either systemic or localized administration of CTLA-Ig has been shown to prolong allograft survival and induce donor-specific tolerance in some transplant models. In this study, we characterized the expression and immunosuppressive effectiveness of adenoviral-mediated CTLA-4Ig gene transfer. We demonstrated transduction of the allografts with AdCTLA-41g resulted in localized expression, permanent graft survival and stable donor-specific tolerance. In addition, by performing simultaneous dual-organ transplantation, we targeted on immunosuppression through a local expression of CTLA-4Ig via adenoviral-mediated gene transfer into pancreatic allografts.

  8. Antibody-dependent NK cell activation is associated with late kidney allograft dysfunction and the complement-independent alloreactive potential of donor-specific antibodies

    Directory of Open Access Journals (Sweden)

    Tristan Legris

    2016-08-01

    Full Text Available Although kidney transplantation remains the best treatment for end-stage renal failure, it is limited by chronic humoral aggression of the graft vasculature by donor-specific antibodies (DSAs. The complement-independent mechanisms that lead to the antibody-mediated rejection (ABMR of kidney allografts remain poorly understood. Increasing lines of evidence have revealed the relevance of natural killer (NK cells as innate immune effectors of antibody-dependent cellular cytotoxicity, but few studies have investigated their alloreactive potential in the context of solid organ transplantation. Our study aimed to investigate the potential contribution of the antibody-dependent alloreactive function of NK cells to kidney graft dysfunction. We first conducted an observational study to investigate whether the cytotoxic function of NK cells is associated with chronic allograft dysfunction. The NK-Cellular Humoral Activation Test (NK-CHAT was designed to evaluate the recipient and antibody-dependent reactivity of NK cells against allogeneic target cells. The release of CD107a/Lamp1+ cytotoxic granules, resulting from the recognition of rituximab-coated B cells by NK cells, was analyzed in 148 kidney transplant recipients (KTRs, mean graft duration: 6.2 years. Enhanced ADCC responsiveness was associated with reduced graft function and identified as an independent risk factor predicting a decline in the estimated glomerular filtration rate (eGFR over a 1-year period (hazard ratio: 2.83. In a second approach, we used the NK-CHAT to reveal the cytotoxic potential of circulating alloantibodies in vitro. The level of CD16 engagement resulting from the in vitro recognition of serum-coated allogeneic B cells or splenic cells was further identified as a specific marker of DSA-induced ADCC. The NK-CHAT scoring of sera obtained from 40 patients at the time of transplant biopsy was associated with ABMR diagnosis. Our findings indicate that despite the administration

  9. Antibody-Dependent NK Cell Activation Is Associated with Late Kidney Allograft Dysfunction and the Complement-Independent Alloreactive Potential of Donor-Specific Antibodies.

    Science.gov (United States)

    Legris, Tristan; Picard, Christophe; Todorova, Dilyana; Lyonnet, Luc; Laporte, Cathy; Dumoulin, Chloé; Nicolino-Brunet, Corinne; Daniel, Laurent; Loundou, Anderson; Morange, Sophie; Bataille, Stanislas; Vacher-Coponat, Henri; Moal, Valérie; Berland, Yvon; Dignat-George, Francoise; Burtey, Stéphane; Paul, Pascale

    2016-01-01

    Although kidney transplantation remains the best treatment for end-stage renal failure, it is limited by chronic humoral aggression of the graft vasculature by donor-specific antibodies (DSAs). The complement-independent mechanisms that lead to the antibody-mediated rejection (ABMR) of kidney allografts remain poorly understood. Increasing lines of evidence have revealed the relevance of natural killer (NK) cells as innate immune effectors of antibody-dependent cellular cytotoxicity (ADCC), but few studies have investigated their alloreactive potential in the context of solid organ transplantation. Our study aimed to investigate the potential contribution of the antibody-dependent alloreactive function of NK cells to kidney graft dysfunction. We first conducted an observational study to investigate whether the cytotoxic function of NK cells is associated with chronic allograft dysfunction. The NK-Cellular Humoral Activation Test (NK-CHAT) was designed to evaluate the recipient and antibody-dependent reactivity of NK cells against allogeneic target cells. The release of CD107a/Lamp1(+) cytotoxic granules, resulting from the recognition of rituximab-coated B cells by NK cells, was analyzed in 148 kidney transplant recipients (KTRs, mean graft duration: 6.2 years). Enhanced ADCC responsiveness was associated with reduced graft function and identified as an independent risk factor predicting a decline in the estimated glomerular filtration rate over a 1-year period (hazard ratio: 2.83). In a second approach, we used the NK-CHAT to reveal the cytotoxic potential of circulating alloantibodies in vitro. The level of CD16 engagement resulting from the in vitro recognition of serum-coated allogeneic B cells or splenic cells was further identified as a specific marker of DSA-induced ADCC. The NK-CHAT scoring of sera obtained from 40 patients at the time of transplant biopsy was associated with ABMR diagnosis. Our findings indicate that despite the administration of

  10. SCHEDULING WITH REJECTION AND NON-IDENTICAL JOB ARRIVALS

    Institute of Scientific and Technical Information of China (English)

    Zhigang CAO; Yuzhong ZHANG

    2007-01-01

    In this paper, we address the scheduling problem with rejection and non-identical job arrivals, in which we may choose not to process certain jobs and each rejected job incurs a penalty.Our goal is to minimize the sum of the total penalties of the rejected jobs and the maximum completion time of the processed ones. For the off-line variant, we prove its NP-hardness and present a PTAS, and for the on-line special case with two job arrivals, we design a best possible algorithm with competitive ratio (√5+1)/2.

  11. Suicide Screening for Prisoners: An Ethical Critique of Research Rejection.

    Science.gov (United States)

    Guinn, David; Burgermeister, Diane M

    2016-01-01

    A retrospective review of medical records was proposed to examine mental health staff compliance with documentation of a suicide assessment tool according to institutional policy on suicide screening within a U.S. correctional facility. A shift in focus was necessary when the proposed study was rejected by the institutional review board. Reasons for the rejection included low perceived benefit versus greater risk to the correctional facility and the need for prisoner informed consent, albeit the design was a retrospective medical record review. Because of this rejection, ethical issues in the prevention of suicide in prisons were examined with implications for the forensic nurse leading quality improvement initiatives.

  12. Pharmacokinetics interactions of monoclonal antibodies.

    Science.gov (United States)

    Ferri, Nicola; Bellosta, Stefano; Baldessin, Ludovico; Boccia, Donatella; Racagni, Giorgi; Corsini, Alberto

    2016-09-01

    The clearance of therapeutic monoclonal antibodies (mAbs) typically does not involve cytochrome P450 (CYP450)-mediated metabolism or interaction with cell membrane transporters, therefore the pharmacokinetics interactions of mAbs and small molecule drugs are limited. However, a drug may affect the clearance of mAbs through the modulation of immune response (e.g., methotrexate reduces the clearance of infliximab, adalimumab, and golimumab, possibly due to methotrexate's inhibitory effect on the formation of antibodies against the mAbs). In addition, mAbs that are cytokine modulators may modify the metabolism of drugs through their effects on P450 enzymes expression. For example, cytokine modulators such as tocilizumab (anti-IL-6 receptor antibody) may reverse the "inhibitory" effect of IL-6 on CYP substrates, resulting in a "normalization" of CYP activities. Finally, a drug may alter the clearance of mAbs by either increasing or reducing the levels of expression of targets of mAbs on the cell surface. For instance, statins and fibrates induce PCSK9 expression and therefore increase cellular uptake and clearance of alirocumab and evolocumab, anti-PCSK9 antibodies. In the present review, we will provide an overview on the pharmacokinetics properties of mAbs as related to the most relevant examples of mAbs-small molecule drug interaction.

  13. [Nephrotoxicity of anti-CD3 monoclonal antibodies].

    Science.gov (United States)

    Alegre, M L; Depierreux, M; Florquin, S; Abramowicz, D; De Pauw, L; Kinnaert, P; Vereerstraeten, P; Goldman, M

    1991-01-01

    The OKT3 monoclonal antibody entails a transient acute nephrotoxicity when used either to prevent or to treat renal allograft rejection. This nephrotoxicity was reproduced experimentally in mice injected with 145-2C11, an anti-CD3 monoclonal antibody which shares many properties with OKT3. Both clinical and experimental data suggest that the renal lesions are due to the systemic release of cytokines that occurs prior to the immunosuppression. Pre-treatment with corticosteroids before the injection of anti-CD3 monoclonal antibody mitigates both the release of cytokines and the nephrotoxicity, in a dose-dependent manner. Experimental data suggest that very high doses of methylprednisolone (50 mg/kg) administered 2 to 3 hours before the monoclonal antibody are necessary to obtain an optimal protection. PMID:1827878

  14. Heme Oxygenase-1 Inhibits HLA Class I Antibody-Dependent Endothelial Cell Activation.

    Directory of Open Access Journals (Sweden)

    Eva Zilian

    Full Text Available Antibody-mediated rejection (AMR is a key limiting factor for long-term graft survival in solid organ transplantation. Human leukocyte antigen (HLA class I (HLA I antibodies (Abs play a major role in the pathogenesis of AMR via their interactions with HLA molecules on vascular endothelial cells (ECs. The antioxidant enzyme heme oxygenase (HO-1 has anti-inflammatory functions in the endothelium. As complement-independent effects of HLA I Abs can activate ECs, it was the goal of the current study to investigate the role of HO-1 on activation of human ECs by HLA I Abs. In cell cultures of various primary human macro- and microvascular ECs treatment with monoclonal pan- and allele-specific HLA I Abs up-regulated the expression of inducible proinflammatory adhesion molecules and chemokines (vascular cell adhesion molecule-1 [VCAM-1], intercellular cell adhesion molecule-1 [ICAM-1], interleukin-8 [IL-8] and monocyte chemotactic protein 1 [MCP-1]. Pharmacological induction of HO-1 with cobalt-protoporphyrin IX reduced, whereas inhibition of HO-1 with either zinc-protoporphyrin IX or siRNA-mediated knockdown increased HLA I Ab-dependent up-regulation of VCAM-1. Treatment with two carbon monoxide (CO-releasing molecules, which liberate the gaseous HO product CO, blocked HLA I Ab-dependent EC activation. Finally, in an in vitro adhesion assay exposure of ECs to HLA I Abs led to increased monocyte binding, which was counteracted by up-regulation of HO-1. In conclusion, HLA I Ab-dependent EC activation is modulated by endothelial HO-1 and targeted induction of this enzyme may be a novel therapeutic approach for the treatment of AMR in solid organ transplantation.

  15. Non-clairvoyant weighted flow time scheduling with rejection penalty

    DEFF Research Database (Denmark)

    Chan, Ho-Leung; Chan, Sze-Hang; Lam, Tak-Wah;

    2012-01-01

    This paper initiates the study of online scheduling with rejection penalty in the non-clairvoyant setting, i.e., the size (processing time) of a job is not assumed to be known at its release time. In the rejection penalty model, jobs can be rejected with a penalty, and the user cost of a job is...... defined as the weighted flow time of the job plus the penalty if it is rejected before completion. Previous work on minimizing the total user cost focused on the clairvoyant single-processor setting [BBC+03,CLL11] and has produced O(1)-competitive online algorithm for jobs with arbitrary weights and...... results assume a processor running at a fixed speed. This paper shows more interesting results on extending the above study to the dynamic speed scaling model, where the processor can vary the speed dynamically and the rate of energy consumption is an arbitrary increasing function of speed. A scheduling...

  16. Community rejection following sexual assault as ‘forced migration’

    Directory of Open Access Journals (Sweden)

    AJ Morgen

    2013-09-01

    Full Text Available When women are banished from their communities following sexual assault, this rejection should be considered an act of forced migration by the administrators of truth commission reparations programmes.

  17. Stem Cells Transplanted in Monkeys without Anti-Rejection Drugs

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_160989.html Stem Cells Transplanted in Monkeys Without Anti-Rejection Drugs Scientists say goal is to create banks of stem cells that could be used for any human patient ...

  18. Seleção de doador não aparentado HLA antibodies and donor selection

    Directory of Open Access Journals (Sweden)

    Margareth Torres

    2010-05-01

    Full Text Available Apesar da presença de anticorpos anti-HLA em transplantes de órgãos sólidos estar associada à rejeição, essa correlação não havia sido pesquisada em transplante alogênico de células progenitoras hematopoéticas (TCPH. Estudos mais recentes na literatura têm demonstrado que a falência da enxertia no TCPH pode ser mediada por aloanticorpos anti-HLA doador especifico (DSA. A especificidade desses anticorpos pode ser evidenciada pelas técnicas de fase sólida, onde os antígenos HLA únicos são aderidos a pérolas de poliestireno, que permite a realização da prova cruzada virtual. Na presença de DSA, é recomendável selecionar outro doador ou realizar as estratégias de remoção dos anticorpos.In spite of Anti-HLA antibodies being associated to rejection in solid organs transplantation, this correlation has not been well established yet in allogenic bone marrow transplantation.Recent studies in the literature have demonstrated that engraftment failure in hematopoietic cell transplantation (HCT can be mediated by donor specific anti-HLA antibodies (DSA. These antibodies specificity can be detected by solid-phase techniques, where single HLA antigens are adhered to microbeads, which allows the interpretation of host reactivity by "virtual crossmatch". In the presence of DSA, it is advisable to either search for another donor or remove the antibodies prior to transplantation.

  19. Sensitive solid-phase detection of donor-specific antibodies as an aid highly relevant to improving allograft outcomes.

    Science.gov (United States)

    Schlaf, Gerald; Pollok-Kopp, Beatrix; Altermann, Wolfgang W

    2014-04-01

    Transplant recipients who have had sensitizing events such as pregnancies, blood transfusions and previous transplants often develop antibodies directed against human leukocyte antigen (HLA)-molecules of the donor tissue. These pre-formed donor-specific antibodies (DSA) represent a high risk of organ failure as a consequence of antibody-mediated hyper-acute or acute allograft rejection. As a first assay to detect DSA, the complement-dependent lymphocytotoxicity assay (CDC) was established more than 40 years ago. However, this assay is characterized by several drawbacks such as a low sensitivity and a high susceptibility to various artificial factors generally not leading to valid and reliable outcomes under several circumstances that are reviewed in this article. Furthermore, only those antibodies that exert complement-fixing activity are detected. As a consequence, novel procedures that act independently of the complement system and that do not represent functional assays were generated in the format of solid phase assays (SPAs) (bead- or ELISA-based). In this article, we review the pros and cons of these sensitive SPA in comparison with the detection of DSA through the use of the traditional methods such as CDC and flow cytometric analyses. Potential drawbacks of the alternative methodological approaches comprising high background reactivity, susceptibility to environmental factors and the possible influence of subjective operators' errors concerning the interpretation of the results are summarized and critically discussed for each method. We provide a forecast on the future role of SPAs reliably excluding highly deleterious DSA, thus leading to an improved graft survival. PMID:24170304

  20. Main feed water pump NPSH control during load rejection transient

    International Nuclear Information System (INIS)

    The paper introduces the damage to the Main feed water pump because of pump cavitation, analysis the disadvantaged impact of pressure reducing during load rejection transient condition, and the characteristic for Main feedwater pump NPSH during load rejection transient condition; summarizes the characteristics of Main feedwater pump NPSH comparing to NPQJVC. What's more, this paper has a lot for commissioning and running the Main feedwater pump. (author)

  1. Fate of manuscripts rejected for publication in the AJR.

    Science.gov (United States)

    Chew, F S

    1991-03-01

    The fate of rejected manuscripts that were originally submitted to the American Journal of Roentgenology (AJR) during the first 5 months of 1986 was investigated to learn whether, when, and where they had been published. AJR, a peer-reviewed journal of diagnostic radiology with a circulation of over 21,000, annually publishes about 500 papers and receives over 11,500 citations. MEDLINE searches conducted 45 to 54 months after the dates of rejection by AJR located 162 (64%) published papers out of a consecutive series of 254 manuscripts rejected by AJR, including 69% of the rejected major papers and 62% of the rejected case reports. The papers had been published in 30 different radiologic and 27 different nonradiologic journals. Most of these journals published fewer papers, had smaller circulations, and had lower impact factors (a ratio of citations received to papers published) than AJR does. The mean time lapse between rejection by AJR and publication in other journals was 15 months. The delay in publication was greater for papers published in nonradiologic and foreign journals than for papers published in radiologic and American journals. The results of this study indicate that rejection of a manuscript by a peer-reviewed journal such as AJR delays but by no means precludes publication. At least 82% of the major papers and 70% of the case reports that are submitted to AJR are eventually published, either in AJR or elsewhere. Because a scientific paper represents not only many hours of writing and manuscript preparation but also a great investment of research time and resources, authors are reluctant to abandon rejected manuscripts. In the majority of cases, submission to other journals gains acceptance and publication. PMID:1899764

  2. Multivisceral transplantation in pigs: a clinicopathological analysis of tissue rejection.

    OpenAIRE

    Mitsuoka,Shintaro; Tanaka,Noriaki; Orita, Kunzo

    1995-01-01

    In this study, we established the surgical procedure and postoperative care of multivisceral transplantation (MVTX) in pigs, and examined the functional changes and rejection pattern of transplanted organs in MVTX. Twenty-two MVTXs were performed without immunosuppression, and nine cases (41%) that survived for 5 days or more after MVTX were used for evaluation. Rejection in grafts including the liver, pancreas, and gastrointestinal tract were assessed histopathologically. On day 5 after tran...

  3. On Properties of Update Sequences Based on Causal Rejection

    OpenAIRE

    Eiter, T.; Fink, M; Sabbatini, G; Tompits, H.

    2001-01-01

    We consider an approach to update nonmonotonic knowledge bases represented as extended logic programs under answer set semantics. New information is incorporated into the current knowledge base subject to a causal rejection principle enforcing that, in case of conflicts, more recent rules are preferred and older rules are overridden. Such a rejection principle is also exploited in other approaches to update logic programs, e.g., in dynamic logic programming by Alferes et al. We give a thoroug...

  4. Higher boron rejection with a new TFC forward osmosis membrane

    KAUST Repository

    Valladares Linares, Rodrigo

    2014-07-17

    Due to the stringent limits for boron in drinking and irrigation water, water treatment facilities have to incur additional treatment to remove boron down to a safe concentration. Forward osmosis (FO) is a membrane technology that may reduce the energy required to remove boron present in seawater. In direct FO desalination hybrid systems, fresh water is recovered from seawater using a recoverable draw solution, FO membranes are expected to show high boron rejection. This study focuses on determining the boron rejection capabilities of a new generation thin-film composite (TFC) FO membrane compared to a first generation cellulose triacetate (CTA) FO membrane. The effects of water permeate flux, membrane structure, draw solute charge, and reverse solute flux on boron rejection were determined. For TFC and CTA FO membranes, experiments showed that when similar operating conditions are applied (e.g. membrane type and draw solute type) boron rejection decreases with increase in permeate flux. Reverse draw solute flux and membrane fouling have no significant impact on boron rejection. Compared to the first generation CTA FO membrane operated at the same conditions, the TFC FO membrane showed a 40% higher boron rejection capability and a 20% higher water flux. This demonstrates the potential for boron removal for new generation TFC FO membranes. © 2014 © 2014 Balaban Desalination Publications. All rights reserved.

  5. Influence of biofouling on pharmaceuticals rejection in NF membrane filtration.

    Science.gov (United States)

    Botton, Sabrina; Verliefde, Arne R D; Quach, Nhut T; Cornelissen, Emile R

    2012-11-15

    The effects of biomass attachment and growth on the surface characteristics and organic micropollutants rejection performance of nanofiltration membranes were investigated in a pilot installation. Biomass growth was induced by dosing of a readily biodegradable carbon source resulting in the formation of a biofouling in the investigated membrane elements. Surface properties and rejection behaviour of a biofouled and virgin membrane were investigated and compared in terms of surface charge, surface energy and hydrophobicity. The last two were accomplished by performing contact angle measurements on fully hydrated membrane surfaces, in order to mimic the operating conditions of a membrane in contact with water. Compared to a virgin membrane, deposition and growth of biofilm did slightly alter the surface charge, which became more negative, and resulted in a higher hydrophilicity of the membrane surface. In addition, the presence of the negatively charged biofilm induced accumulation of positively charged pharmaceuticals within the biomass layer, which probably also hindered back diffusion. This caused a reduction in rejection efficiency of positively charged solutes but did not alter rejection of neutral and negatively charged pharmaceuticals. Pharmaceuticals rejection was found to positively correlate with the specific free energy of interaction between virgin or biofouled membranes and pharmaceuticals dissolved in the water phase. The rejection values obtained with both virgin and biofouled membranes were compared and found in good agreement with the predictions calculated with a solute transport model earlier developed for high pressure filtration processes. PMID:22960036

  6. The private rejection of unfair offers and emotional commitment.

    Science.gov (United States)

    Yamagishi, Toshio; Horita, Yutaka; Takagishi, Haruto; Shinada, Mizuho; Tanida, Shigehito; Cook, Karen S

    2009-07-14

    In a series of experiments, we demonstrate that certain players of an economic game reject unfair offers even when this behavior increases rather than decreases inequity. A substantial proportion (30-40%, compared with 60-70% in the standard ultimatum game) of those who responded rejected unfair offers even when rejection reduced only their own earnings to 0, while not affecting the earnings of the person who proposed the unfair split (in an impunity game). Furthermore, even when the responders were not able to communicate their anger to the proposers by rejecting unfair offers in a private impunity game, a similar rate of rejection was observed. The rejection of unfair offers that increases inequity cannot be explained by the social preference for inequity aversion or reciprocity; however, it does provide support for the model of emotion as a commitment device. In this view, emotions such as anger or moral disgust lead people to disregard the immediate consequences of their behavior, committing them to behave consistently to preserve integrity and maintain a reputation over time as someone who is reliably committed to this behavior. PMID:19564602

  7. Donor MHC gene to mitigate rejection of transplantation in recipient mice

    Institute of Scientific and Technical Information of China (English)

    LI Tong; ZHANG Zhi-tai; LI Hui; YAN Jun; TAN Jia-li; L(U) Yue-ping; HOU Sheng-cai; LI Shen-tao; XU Qing; TONG Xue-hong; DING Jie

    2011-01-01

    Background Donor organ rejection continues to be a significant problem for patients receiving transplants.We therefore tested whether transferring a donor's major histocompatibility complex (MHC) gene to the recipient would mitigate the rejection of transplanted hearts in mice.Methods H-2Kkgene from donor mice was amplified using nested polymerase chain reaction (PCR) and ligated into a mammalian expression vector,which was then transfected into thymus ground mass cells collected from the recipients.Clones stably expressing the transgene were then injected into the recipients' thymus visualized using ultrasound.Control mice were administered cells previously transfected with empty vector.Following heart transplantation,cardiac activity was monitored electrocardiographically.Recipient thymus cells were tested for MHC antigenicity using flow cytometry and spleen cells were subjected to mixed lymphocyte culture tests.Finally,the transplanted hearts were sectioned,stained and examined under light microscopy.Results Southern analysis following nested PCR revealed clear expression of H-2Kk gene.Following transplantation,electrocardiosignals were detectable highly significantly longer in recipients administered thymal cells expressing donor H-2Kk than in those receiving control cells.Flow cytometric analysis using an anti-H-2Kk antibody confirmed its expression in H-2Kk treated recipients but not in control mice.Mixed lymphocyte cultures containing H-2Kk treated cells showed significantly less proliferation than those containing control cells.Hearts from control mice showed substantially greater lymphocyte infiltration than those from H-2Kk treated mice and large areas of necrosis.Conclusion Rejection of transplanted hearts can be mitigated substantially by introducing the donor's MHC into the recipient.

  8. Soluble OX40L favors tumor rejection in CT26 colon carcinoma model.

    Science.gov (United States)

    Serebrovskaya, Ekaterina O; Yuzhakova, Diana V; Ryumina, Alina P; Druzhkova, Irina N; Sharonov, George V; Kotlobay, Alexey A; Zagaynova, Elena V; Lukyanov, Sergey A; Shirmanova, Marina V

    2016-08-01

    OX40 receptor-expressing regulatory T cells (Tregs) populate tumors and suppress a variety of immune cells, posing a major obstacle for cancer immunotherapy. Different ways to functionally inactivate Tregs by triggering OX40 receptor have been suggested, including anti-OX40 antibodies and Fc:OX40L fusion proteins. To investigate whether the soluble extracellular domain of OX40L (OX40Lexo) is sufficient to enhance antitumor immune response, we generated an OX40Lexo-expressing CT26 colon carcinoma cell line and studied its tumorigenicity in immunocompetent BALB/c and T cell deficient nu/nu mice. We found that soluble OX40L expressed in CT26 colon carcinoma favors the induction of an antitumor response which is not limited just to cells co-expressing EGFP as an antigenic determinant, but also eliminates CT26 cells expressing another fluorescent protein, KillerRed. Tumor rejection required the presence of T lymphocytes, as indicated by the unhampered tumor growth in nu/nu mice. Subsequent re-challenge of tumor-free BALB/c mice with CT26 EGFP cells resulted in no tumor growth, which is indicative of the formation of immunological memory. Adoptive transfer of splenocytes from mice that successfully rejected CT26 OX40Lexo EGFP tumors to naïve mice conferred 100% resistance to subsequent challenge with the CT26 EGFP tumor. PMID:27203665

  9. Role of MICA antibodies in solid organ transplantation.

    Science.gov (United States)

    Luo, Lei; Li, Zhengyu; Wu, Weidong; Luo, Guangheng; Xu, Chuan; Sun, Zhaolin; Mei, Hong

    2014-02-01

    As a potential transplant antigen, major histocompatibility complex class I chain-related gene A (MICA) antigen, has attracted increased attention because of its possible role in solid organ transplantation. There are two MICA forms, and MICA antibodies and soluble MICA (sMICA) have been found in the serum of transplant recipients. We searched MEDLINE, EMBASE, and the Cochrane Library for original reports of clinical studies involving the effect of MICA on outcomes of renal, heart, lung, and liver transplantation. In addition to the human leukocyte antigen antigens, which elicit a strong immune response, the polymorphic MICA antigens induce production of MICA antibodies and sMICA. A number of clinical studies have shown that MICA antibodies correlate with an increased incidence of rejection and a decreased allograft survival rate following renal or heart transplantation. Although it is clearly associated with chronic rejection of lung allografts, no such correlation was found for liver transplantation. Moreover, sMICA showed a negative association with acute rejection (AR) and may be a good predictor of heart transplant outcomes. These data suggest MICA expression patterns and regulatory function may be tissue specific and that different transplants have different organ-specific outcomes.

  10. Mice aorta loop grafting: A new model which separate vascular rejection and neointimal formation in chronic rejection

    Institute of Scientific and Technical Information of China (English)

    陈勇; 窦科峰; 何勇; 孙凯

    2003-01-01

    Objective: To study the cause and mechanism of transplantation vasculopathy which characterized by accelerated graft arteriosclerosis (AGA), we established a mouse aorta graft model. Methods: A segment of thoracic aortas of B10.A (2R) mice were transplanted to C57BL/10 mice abdominal aorta by end to side anastomoses. The different time point collected grafts were analyzed by morphological, histochemical and electro microscopic methods. Results: Rejection was manifested as a concentric progressive destruction of the smooth muscle cells. In contrast, the endothelial inflammation and subsequent neointimal proliferation characteristic of AGA was localized to the regions of turbulent flow, i.e. the junction of the graft with the recipient aorta. Conclusion: This model separates the processes of rejection and neointimal formation which usually manifested together in the lesion of AGA, elucidate that different mechanisms control vascular rejection and neointimal formation in chronic rejection.

  11. Not self-focused attention but negative beliefs affect poor social performance in social anxiety : An investigation of pathways in the social anxiety-social rejection relationship

    NARCIS (Netherlands)

    Voncken, Marisol J.; Dijk, Corine; de Jong, Peter J.; Roelofs, Jeffrey

    2010-01-01

    Patients with social anxiety disorder (SAD) not only fear negative evaluation but are indeed less likeable than people without SAD. Previous research shows social performance to mediate this social anxiety-social rejection relationship. This study studied two pathways hypothesized to lead to poor so

  12. The effect of pregnancy on humoral rejection in patients after vascularized organ transplantation.

    Science.gov (United States)

    Cyganek, A; Nowaczyk, M; Sańko-Resmer, J; Pietrzak, B; Grzechocińska, B; Pączek, L; Międzybrodzki, R; Wielgoś, M

    2015-11-01

    The aim of the study was to evaluate the effect of pregnancy on the production of donor- and nondonor-specific anti-human leukocyte antigen antibodies (anti-HLA Abs) in organ allograft recipients. The study group included four pregnant kidney (RT) and four liver (LT) transplant recipients. The genotype of HLA class I (A, B) and class II (DR) antigens was assessed. Anti-HLA antibodies class I and II were evaluated between 36 and 40 weeks' gestation. Two different control groups consisted of the following: group I (n=8) with nonpregnant RT (n=6) and LT recipients (n=2), and group II with healthy pregnant women (n=10) with anti-HLA Abs detected between 38 and 41 weeks' gestation. The HLA genotype was determined in fathers of the fetuses from the study group and group II controls. Half of group II controls had donor-specific anti-HLA (A, B, and/or DR) Abs, while nondonor-specific anti-HLA Abs were detected in all subjects from that group. Anti-HLA Abs were found in all group II controls. In the study group, anti-HLA Abs were found in only two LT recipients and one RT recipient, but they were not confirmed as donor-specific. Anti-HLA antibodies were not detected in the study group, whereas six out of ten group II controls had anti-HLA Abs against the HLA of the child's father. Pregnancy in vascularized organ recipients does not trigger the mechanism of humoral rejection involving anti-HLA class I and II antibodies with a potentially adverse impact on graft function. PMID:26469990

  13. Synthetic Antibodies for Reversible Cell Recognition

    Science.gov (United States)

    Zhou, Jing Zhou

    2011-12-01

    Antibody-mediated cell recognition plays a critical role in various biological and biomedical applications. However, strong antibody-cell interactions can lead to the difficulty of separating antibodies from the bound cells in a simple and non-destructive manner, which is often necessary to numerous applications such as cell sorting or separation. Thus, this thesis research is aimed to create an antibody-like nanomaterial with the function of reversible cell recognition It was hypothesized that nucleic acid aptamer and dendrimer could be used as fundamental structural components to develop an antibody-like nanomaterial. The aptamer functions as the binding site of an antibody; the dendrimer is used as a robust, defined nano-scaffold to support the aptamer and to carry small molecules (e.g., fluorophores). To test this hypothesis, a novel method was first developed to discover the essential nucleotides of full-length aptamers to mimic the binding sites of antibodies. The essential nucleotides were further conjugated with a dendrimer to synthesize a monovalent aptamer-dendrimer nanomaterial. The results clearly showed that the essential nucleotides could maintain high affinity and specificity after tethered on dendrimer surface. To further test the hypothesis that antibody-like nanomaterials can be rationally designed to acquire the capability of reversible cell recognition, an aptamer that was selected at 0 °C was used as a model to synthesize a "Y-shaped" nanomaterial by conjugating two aptamers to the same dendrimer. The results showed that the nanomaterial-cell interaction could be affected by the distance between two binding aptamers. In addition, the "Y-shaped" antibody-like nanomaterial could bind target cells more strongly than its monovalent control. Importantly, the strong cell-nanomaterial interaction could be rapidly reversed when the temperature was shifted from 0 °C to 37 °C. In summary, we developed a synthetic antibody that can not only mimic the

  14. INTRATHYMIC INOCULATION OF LIVER SPECIFIC ANTIGEN ALLEVIATES LIVER TRANSPLANT REJECTION

    Institute of Scientific and Technical Information of China (English)

    贾长库; 郑树森; 朱有法

    2004-01-01

    Objective To study the effects of liver specific antigen (LSA) on liver allotransplantation rejection. Methods Orthotopic liver transplantation was performed in this study. Group Ⅰ: syngeneic control (Wistar-to-Wistar); Group Ⅱ: acute rejection (SD-to-Wistar). Group Ⅲ: thymic inoculation of SD rat LSA day 7 before transplantation. The observation of general condition and survival time, rejection grades and the NF-κB activity of splenocytes were used to analyze severity of acute rejection and immune state of animals in different groups. Results The general condition of group Ⅰ was fair post transplantation with no sign of rejection. All recipients of group Ⅱ died within days 9 to 13 post transplantation with median survival time of 10.7 ±1.37 days. As for group Ⅲ, 5 out of 6 recipients survived for a long period with remarkably better general condition than that of group Ⅱ. Its rejection grades were significantly lower than group Ⅱ (P< 0.05).NF-κB activity was only detected in group Ⅰ between days 5 and 7 after transplantation, whereas high activity of NF-κB was detected at all points in group Ⅱ and low NF-κB activity was detected in group Ⅲ which was significantly lower than that of group Ⅱ (P < 0.05). Conclusions LSA is an important transplantation antigen directly involved in the immunorejection of liver transplantation. Intrathymic inoculation of LSA can alleviate the rejection of liver allotransplantation,grafts survive for a period of time thereby, allowing a novel way to liver transplantation immunotolerance.

  15. Detection of human leukocyte antigen compatibility and antibodies in liver transplantation in China

    Institute of Scientific and Technical Information of China (English)

    Xue-Qin Meng; Xuan Zhang; Jun Fan; Lin Zhou; Bing Hao; Xiao-Ming Chen; Wei-Hang Ma; Shu-Sen Zheng

    2009-01-01

    BACKGROUND: The exact roles of human leukocyte antigen (HLA) compatibility, HLA antibodies and underlying diseases in acute rejection of liver transplants are not clear. Moreover, cytomegalovirus (CMV) infection, one of the most common infections after transplantation, is related to HLA genotype and the incidence of acute rejection. METHODS: Since there are controversial reports, we analyzed the impact of HLA matching, HLA antibodies and underlying diseases in 38 liver transplant recipients in China, and assessed the association of CMV infection and HLA compatibility. RESULTS: The frequency of no HLA compatibility was high in patients without antigenemia (P=0.019). All 17 patients with HLA-A matching developed antigenemia (P0.05). In patients with acute rejection, no differences were found in the incidence of acute rejection in transplants for hepatitis B, tumors, or combined hepatitis B and tumors (P>0.05).CONCLUSIONS: There are fewer acute rejections in transplants with more HLA compatibilities. Speciifc investigations of underlying diseases and HLA typing may be necessary in liver transplantation. The mechanisms of CMV infection and HLA matching should be further studied. HLA before transplantation should be examined for the prevention of acute rejection and CMV infection.

  16. The Role of Complement in Antibody Therapy for Infectious Diseases.

    Science.gov (United States)

    Wibroe, Peter P; Helvig, Shen Y; Moein Moghimi, S

    2014-04-01

    The complement system is part of the innate immune system, eliciting central immunoregulatory functions. Detection of foreign surfaces is either achieved through complement-specific patternrecognition molecules or mediated by antigen recognition of antibodies. Immunoglobulin A (IgA), IgG, and IgM all have the potential to initiate a complement response, with the efficiency and response development closely related to the antibody isotype, multimeric state, and degree of glycosylation. A group of serum proteins constitutes the central effector functions of complement, thus allowing direct cell lysis, opsonization, and inflammation. These effector functions can be used in antibody therapies, especially against infectious diseases, as the target membranes lack complement regulatory proteins. The relative contribution of each function and the interplay with direct antibody-mediated clearance is not fully exploited, thus suggesting an option for further rational optimization of antibody therapies.

  17. Monoclonal antibodies and cancer

    International Nuclear Information System (INIS)

    The usefulness of radiolabeled monoclonal antibodies for imaging and treatment of human (ovarian) cancer was investigated. A review of tumor imaging with monoclonal antibodies is presented. Special attention is given to factors that influence the localization of the antibodies in tumors, isotope choice and methods of radiolabeling of the monoclonal antibodies. Two monoclonal antibodies, OC125 and OV-TL3, with high specificity for human epithelial ovarian cancer are characterized. A simple radio-iodination technique was developed for clinical application of the monoclonal antibodies. The behavior of monoclonal antibodies in human tumor xenograft systems and in man are described. Imaging of tumors is complicated because of high background levels of radioactivity in other sites than the tumor, especially in the bloodpool. A technique was developed to improve imaging of human tumor xenographs in nude mice, using subtraction of a specific and a non-specific antibody, radiolabeled with 111In, 67Ga and 131I. To investigate the capability of the two monoclonal antibodies, to specifically localize in human ovarian carcinomas, distribution studies in mice bearing human ovarian carcinoma xenografts were performed. One of the antibodies, OC125, was used for distribution studies in ovarian cancer patients. OC125 was used because of availability and approval to use this antibody in patients. The same antibody was used to investigate the usefulness of radioimmunoimaging in ovarian cancer patients. The interaction of injected radiolabeled antibody OC125 with circulating antigen and an assay to measure the antibody response in ovarian cancer patients after injection of the antibody is described. 265 refs.; 30 figs.; 19 tabs

  18. The composition of the microbiota modulates allograft rejection.

    Science.gov (United States)

    Lei, Yuk Man; Chen, Luqiu; Wang, Ying; Stefka, Andrew T; Molinero, Luciana L; Theriault, Betty; Aquino-Michaels, Keston; Sivan, Ayelet S; Nagler, Cathryn R; Gajewski, Thomas F; Chong, Anita S; Bartman, Caroline; Alegre, Maria-Luisa

    2016-07-01

    Transplantation is the only cure for end-stage organ failure, but without immunosuppression, T cells rapidly reject allografts. While genetic disparities between donor and recipient are major determinants of the kinetics of transplant rejection, little is known about the contribution of environmental factors. Because colonized organs have worse transplant outcome than sterile organs, we tested the influence of host and donor microbiota on skin transplant rejection. Compared with untreated conventional mice, pretreatment of donors and recipients with broad-spectrum antibiotics (Abx) or use of germ-free (GF) donors and recipients resulted in prolonged survival of minor antigen-mismatched skin grafts. Increased graft survival correlated with reduced type I IFN signaling in antigen-presenting cells (APCs) and decreased priming of alloreactive T cells. Colonization of GF mice with fecal material from untreated conventional mice, but not from Abx-pretreated mice, enhanced the ability of APCs to prime alloreactive T cells and accelerated graft rejection, suggesting that alloimmunity is modulated by the composition of microbiota rather than the quantity of bacteria. Abx pretreatment of conventional mice also delayed rejection of major antigen-mismatched skin and MHC class II-mismatched cardiac allografts. This study demonstrates that Abx pretreatment prolongs graft survival, suggesting that targeting microbial constituents is a potential therapeutic strategy for enhancing graft acceptance.

  19. Gene Expression Profiling on Acute Rejected Transplant Kidneys with Microarray

    Institute of Scientific and Technical Information of China (English)

    Deping LI; Kang WANG; Yong DAI; Tianyu LV

    2008-01-01

    To investigate the gene expression profiles in acute allograft rejection of renal trans- plantation, and identify the markers for the early diagnosis of acute rejection, heterotopic kidney transplantation was performed by using F344 or Lewis donors and Lewis recipients. No immunosup- pressant was used. Renal grafts were harvested on days 3, 7, and 14. A commercial microarray was used to measure gene expression levels in day-7 grafts. The expression levels of 48 genes were up-regulated in the allograft in comparison with the isograft control, and interferon-y-induced GTPase gene was most significantly up-regulated in allografts. It is concluded that a variety of pathways are involved in organ transplant rejection which is dynamic and non-balanced. IFN-inducible genes, such as IGTP, may play an important role in the rejection. A lot of important factors involved in acute re- jection are unnecessary but sufficient conditions for the rejection. We are led to conclude that it is virtually impossible to make an early diagnosis based on a single gene marker, but it could he achieved on the basis of a set of markers.

  20. The composition of the microbiota modulates allograft rejection.

    Science.gov (United States)

    Lei, Yuk Man; Chen, Luqiu; Wang, Ying; Stefka, Andrew T; Molinero, Luciana L; Theriault, Betty; Aquino-Michaels, Keston; Sivan, Ayelet S; Nagler, Cathryn R; Gajewski, Thomas F; Chong, Anita S; Bartman, Caroline; Alegre, Maria-Luisa

    2016-07-01

    Transplantation is the only cure for end-stage organ failure, but without immunosuppression, T cells rapidly reject allografts. While genetic disparities between donor and recipient are major determinants of the kinetics of transplant rejection, little is known about the contribution of environmental factors. Because colonized organs have worse transplant outcome than sterile organs, we tested the influence of host and donor microbiota on skin transplant rejection. Compared with untreated conventional mice, pretreatment of donors and recipients with broad-spectrum antibiotics (Abx) or use of germ-free (GF) donors and recipients resulted in prolonged survival of minor antigen-mismatched skin grafts. Increased graft survival correlated with reduced type I IFN signaling in antigen-presenting cells (APCs) and decreased priming of alloreactive T cells. Colonization of GF mice with fecal material from untreated conventional mice, but not from Abx-pretreated mice, enhanced the ability of APCs to prime alloreactive T cells and accelerated graft rejection, suggesting that alloimmunity is modulated by the composition of microbiota rather than the quantity of bacteria. Abx pretreatment of conventional mice also delayed rejection of major antigen-mismatched skin and MHC class II-mismatched cardiac allografts. This study demonstrates that Abx pretreatment prolongs graft survival, suggesting that targeting microbial constituents is a potential therapeutic strategy for enhancing graft acceptance. PMID:27322054

  1. Rejection mechanisms for contaminants in polymeric reverse osmosis membranes

    CERN Document Server

    Shen, Meng; Lueptow, Richard M

    2016-01-01

    Despite the success of reverse osmosis (RO) for water purification, the molecular-level physico-chemical processes of contaminant rejection are not well understood. Here we carry out NEMD simulations on a model polyamide RO membrane to understand the mechanisms of transport and rejection of both ionic and neutral contaminants in water. We observe that the rejection changes non-monotonously with ion sizes. In particular, the rejection of urea, 2.4 A radius, is higher than ethanol, 2.6 A radius, and the rejections for organic solutes, 2.2-2.8 A radius, are lower than Na+, 1.4 A radius, or Cl-, 2.3 A radius. We show that this can be explained in terms of the solute accessible intermolecular volume in the membrane and the solute-water pair interaction energy. If the smallest open spaces in the membrane's molecular structure are all larger than the hydrated solute, then the solute-water pair interaction energy does not matter. However, when the open spaces in the polymeric structure are such that solutes have to s...

  2. Ipsilateral Lymphadenectomy to Inhibit Corneal Allograft Rejection in Rats

    Institute of Scientific and Technical Information of China (English)

    LING Shiqi; HU Yanhua

    2005-01-01

    In order to investigate the ipsilateral lymphadenectomy for inhibiting rejection in rat corneal transplantation, corneal allogenic transplantation models were established in rats. Eighteen female Wister rats were used as donors, and 36 Sprague Dawley rats as recipients. After penetrating corneal transplantation, recipients were randomly divided into 3 groups: group A (control group);group B, the ipsilateral lymphadenectomy group; group C, the bilateral lymphadenectomy group.Among 12 rats in each group, the corneas of 2 rats in each group were used for pathological study at day 14 after the transplantation, and the remaining 10 rats were used for studying corneal rejection by a slit lamp. The time points when allograft rejection occurred were recorded and mean survival time (MST) was compared. The results showed that MST in groups B and C was 46.30±9.464 days and 44.43 ± 7. 604 days, respectively, which was significantly prolonged as compared with that in group A (10.71±1. 567 days, P<0.01). There was no significant difference in MST between groups B and C (P>0.05). Itwas concluded that both bilateral and ipsilateral lymphadenectomy therapies could effectively inhibit the corneal allograft rejection. Ipsilateral lymphadenectomy is a less complex surgical procedure and is just as effective in preventing rejection.

  3. Cytolytic antibodies to melanocytes in vitiligo.

    Science.gov (United States)

    Cui, J; Arita, Y; Bystryn, J C

    1993-06-01

    Patients with vitiligo have been found to have circulating antibodies to pigment cells. To evaluate the functional activity of these antibodies, a highly sensitive europium release assay was used to compare complement-mediated cytolysis of human melanocytes by sera of 56 patients with vitiligo (20 with active disease, 25 with inactive disease, 11 with unidentified disease activity) and 47 control individuals. Significant melanocyte lysis was mediated by 32 (57%) of the patients with vitiligo but by only three (6%) of the control sera (p < 0.001), and by 17 (85%) of 20 patients with active vitiligo versus 11 (44%) of 25 patients with inactive disease (p < 0.025). Mean melanocyte lysis by vitiligo sera was 24% versus 6% by control sera (p < 0.0001). A subset of 12 vitiligo sera with high titers of cytolytic antibodies to melanocytes (34% mean cytolysis) reacted minimally (< 2% mean cytolysis) to a panel of control cells that included human and murine melanomas, human fibroblasts, lung carcinoma, and rhabdomyosarcoma. These findings indicate that antibodies present in patients with vitiligo have the functional ability to selectively kill melanocytes and are more common in active disease. These observations support, but do not prove, the hypothesis that vitiligo is an autoimmune disease and that anti-pigment cell antibodies have a role in inducing the disease. PMID:8496621

  4. Neutralizing antibodies in hepatitis C virus infection

    Institute of Scientific and Technical Information of China (English)

    Mirjam B Zeisel; Samira Fafi-Kremer; Isabel Fofana; Heidi Barth; Fran(c)oise Stoll-Keller; Michel Doffo(e)l; Thomas F Baumert

    2007-01-01

    Hepatitis C virus (HCV) is a major cause of hepatitis world-wide. The majority of infected individuals develop chronic hepatitis which can then progress to liver cirrhosis and hepatocellular carcinoma. Spontaneous viral clearance occurs in about 20%-30% of acutely infected individuals and results in resolution of infection without sequaelae. Both viral and host factors appear to play an important role for resolution of acute infection. A large body of evidence suggests that a strong, multispecific and long-lasting cellular immune response appears to be important for control of viral infection in acute hepatitis C. Due too the lack of convenient neutralization assays,the impact of neutralizing responses for control of viral infection had been less defined. In recent years, the development of robust tissue culture model systems for HCV entry and infection has finally allowed study of antibody-mediated neutralization and to gain further insights into viral targets of host neutralizing responses.In addition, detailed analysis of antibody-mediated neutralization in individual patients as well as cohorts with well defined viral isolates has enabled the study of neutralizing responses in the course of HCV infection and characterization of the impact of neutralizing antibodies for control of viral infection. This review will summarize recent progress in the understanding of the molecular mechanisms of antibody-mediated neutralization and its impact for HCV pathogenesis.(C) 2007 The WJG Press. All rights reserved.

  5. Administration of an anti-interleukin 2 receptor monoclonal antibody prolongs cardiac allograft survival in mice

    OpenAIRE

    1985-01-01

    Administration of the monoclonal antibody M7/20, which binds to the murine interleukin-2 (IL) receptor, significantly prolongs cardiac allograft survival in two H-2-incompatible strain combinations of inbred mice. The results support the important role of the IL-2 receptor in the mechanism of graft rejection, and suggest its suitability as a target for immunosuppressive therapy.

  6. Differential role of CD4+ cells in the sensitization and effector phases of accelerated graft rejection.

    Science.gov (United States)

    Sablinski, T; Sayegh, M H; Hancock, W W; Kut, J P; Kwok, C A; Milford, E L; Tilney, N L; Kupiec-Weglinski, J W

    1991-01-01

    Although CD4-targeted therapy markedly prolongs survival of organ allografts in naive rodents, its effects in primed hosts have not been studied. In our model of accelerated rejection (ACCR) of cardiac Tx in rats, treatment with BWH-4, a CD4 mAb (IgG2a), in the sensitization (between skin and heart Tx) but not in the effector (after cardiac Tx) phase, abrogated fulminant less than 36 hr rejection response and prolonged Tx survival to ca. 11 days. This effect correlated with decreased frequency of circulating CD4+ cells, but it did not depend upon their total depletion. It was also related to BWH-4 mAb-mediated elimination/depression of strong anti-donor humoral responses and cellular responses as determined by lymphocyte-mediated cytotoxicity and mixed lymphocyte reaction and mounted otherwise at the time of engraftment by untreated sensitized hosts. Immunoperoxidase studies of cardiac Tx from BWH-4-conditioned recipients revealed reduced T and B cell activities, reflected in abolition/reduction in deposition of humoral mediators, infiltrating cells, intra-Tx elaboration of interleukin-2 and interferon-gamma, and cell activation. This first report of the successful use of CD4 mAb in sensitized recipients of vascularized organ Tx, stresses the role of CD4+ cells as potential targets for immunosuppression in the sensitization phase of accelerated Tx injury. The beneficial therapeutic effect, probably due to both depletion and functional inhibition of CD4+ T cells, has been achieved by using relatively low doses of BWH-4 mAb. PMID:1824805

  7. [VGKC-complex antibodies].

    Science.gov (United States)

    Watanabe, Osamu

    2013-04-01

    Various antibodies are associated with voltage-gated potassium channels (VGKCs). Representative antibodies to VGKCs were first identified by radioimmunoassays using radioisotope-labeled alpha-dendrotoxin-VGKCs solubilized from rabbit brain. These antibodies were detected only in a proportion of patients with acquired neuromyotonia (Isaacs' syndrome). VGKC antibodies were also detected in patients with Morvan's syndrome and in those with a form of autoimmune limbic encephalitis. Recent studies indicated that the "VGKC" antibodies are mainly directed toward associated proteins (for example LGI-1 and CASPR-2) that complex with the VGKCs themselves. The "VGKC" antibodies are now commonly known as VGKC-complex antibodies. In general, LGI-1 antibodies are most commonly detected in patients with limbic encephalitis with syndrome of inappropriate secretion of antidiuretic hormone. CASPR-2 antibodies are present in the majority of patients with Morvan's syndrome. These patients develop combinations of CNS symptoms, autonomic dysfunction, and peripheral nerve hyperexcitability. Furthermore, VGKC-complex antibodies are tightly associated with chronic idiopathic pain. Hyperexcitability of nociceptive pathways has also been implicated. These antibodies may be detected in sera of some patients with neurodegenerative diseases (for example, amyotrophic lateral sclerosis and Creutzfeldt-Jakob disease).

  8. An image rejection circuit with sign detection only

    OpenAIRE

    Lerstaveesin, Supisa

    2006-01-01

    In direct-conversion receivers, radio frequency (RF) signals are down-converted to zero or low intermediate frequency (IF) using complex in-phase and quadrature (I/Q) mixers with no prior image filtering. Due to I/Q path gain and phase errors, image leaks into the signal band during the down-conversion process. A generic image rejection algorithm is proposed to reject image in the baseband using a zero-forcing sign-sign adaptive feedback concept. The orthonormal property of complex I/Q channe...

  9. Solar dynamic organic Rankine cycle heat rejection system simulation

    Science.gov (United States)

    Havens, V. N.; Ragaller, D. R.; Namkoong, D.

    1987-01-01

    The use of a rotary fluid management device (RFMD) and shear flow condenser for two-phase fluid management in microgravity organic Rankine cycle (ORC) applications is examined. A prototype of the proposed Space Station ORC heat rejection system was constructed to evaluate the performance of the inventory control method. The design and operation of the RFMD, shear flow condenser, and inventory control fluid accumulator are described. A schematic diagram of the ORC, RFMD, and condenser, and a functional diagram of the heat rejection system for the ORC are presented.

  10. Belief decision support and reject for textured images characterization

    CERN Document Server

    Martin, Arnaud

    2008-01-01

    The textured images' classification assumes to consider the images in terms of area with the same texture. In uncertain environment, it could be better to take an imprecise decision or to reject the area corresponding to an unlearning class. Moreover, on the areas that are the classification units, we can have more than one texture. These considerations allows us to develop a belief decision model permitting to reject an area as unlearning and to decide on unions and intersections of learning classes. The proposed approach finds all its justification in an application of seabed characterization from sonar images, which contributes to an illustration.

  11. Causes of rejection of beef bulls in breeding soundness evaluation

    Directory of Open Access Journals (Sweden)

    Silvio Renato Oliveira Menegassi

    2012-07-01

    Full Text Available The objective of this study was to analyze the rates of rejection in the different steps of the breeding soundness evaluation of beef bulls in the state of Rio Grande do Sul, Brazil. The breeding soundness of 22,113 young and mature bulls of 14 beef breeds, participating in the Program of Reproductive Evaluation (PARTO was evaluated in the experiment. Data concerning to the causes of rejection in the four steps of the breeding soundness evaluation (general physical examination, genital tract examination, semen evaluation and sexual behavior assessment were analyzed by the Chi-square test and univariate regression analysis. According to year, general physical examination, genital tract examination and semen evaluation determined the rejection of 0.9% to 2.5%, 5.1% to 7.7%, 1.8% to 5.3%; and 4.2% to 6.7%, 7.3 to 9.3%, and 2.5% to 5.5% of young and mature bulls, respectively. Mature bulls presented higher chances of rejection than young bulls in the general physical examination in every year evaluated; as to the genital tract examination, their chances of rejection were higher in years I and II, but not in year III. In the semen evaluation, there was no difference between the ages assessed in any of the three years evaluated. Sexual behavior assessment accounted for the rejection of 1.9 to 6.0% of the young bulls and 2.9% to 3.9% of mature bulls, in accordance with the years evaluated; in years I and II, mature bulls presented higher rejection rates than young bulls. These results confirm the importance of performing all steps of the breeding soundness evaluation, including the sexual behavior assessment as a work routine, rather than an additional, optional stage of the evaluation, which should be carried out before the breeding season. The results indicate the relationship between bull age and rejection rate in the breeding soundness evaluation.

  12. Acute renal transplant rejections: A single center experience

    Directory of Open Access Journals (Sweden)

    Jabur Wael

    2008-01-01

    Full Text Available We undertook this observational study to assess the incidence of acute rejections (AR in the first six months after transplantation at Al-Karama Hospital, Iraq. Sixty eight patients (49 males and 19 females underwent renal transplantation in 2006 and were followed up weekly. Forty six received kidneys from related donors and 22 from unrelated donors. During the first six months after transplantation AR occurred in 16 patients (23%; 11 (23% related and 5 (23% unrelated donor transplantation. We conclude that the incidence of acute rejection was similar in related and unrelated donor transplantation and the general incidence was comparable to that reported from most centers.

  13. Consecutive Low Doses of Cyclosporine A Induce Pro-Inflammatory Cytokines and Accelerate Allograft Skin Rejection

    Directory of Open Access Journals (Sweden)

    Luis I. Terrazas

    2011-05-01

    Full Text Available Cyclosporine A (CsA is a fungus-derived molecule with potent immunosuppressive activity that has been largely used to downregulate cell-mediated immune responses during transplantation. However, previous data have indicated that CsA shows immunomodulatory activity that relays on the antigen concentration and the dose of CsA used. To test the hypothesis that minimal doses of CsA may show different outcomes on grafts, we used an experimental model for skin transplants in mice. ICR outbred mice received skin allografts and were either treated daily with different doses of CsA or left untreated. Untreated mice showed allograft rejection within 14 days, with graft necrosis, infiltration of neutrophils and macrophages and displayed high percentages of CD8+ T cells in the spleens, which were associated with high serum levels of IL-12, IFN-g and TNF-α. As expected, mice treated with therapeutic doses of CsA (15 mg/kg did not show allograft rejection within the follow-up period of 30 days and displayed the lowest levels of IL-12, IFN-g and TNF-α as well as a reduction in CD8+ lymphocytes. In contrast, mice treated with consecutive minimal doses of CsA (5 × 10−55 mg/kg displayed an acute graft rejection as early as one to five days after skin allograft; they also displayed necrosis and strong inflammatory infiltration that was associated with high levels of IL-12, IFN-g and TNF-α. Moreover, the CD4+ CD25hiFoxP3+ subpopulation of cells in the spleens of these mice was significantly inhibited compared with animals that received the therapeutic treatment of CsA and those treated with placebo. Our data suggest that consecutive, minimal doses of CsA may affect Treg cells and may stimulate innate immunity.

  14. Activation of counter-regulatory mechanisms in a rat renal acute rejection model

    Directory of Open Access Journals (Sweden)

    Salomon Daniel R

    2008-02-01

    Full Text Available Abstract Background Microarray analysis provides a powerful approach to identify gene expression alterations following transplantation. In patients the heterogeneity of graft specimens, co-morbidity, co-medications and the challenges in sample collection and preparation complicate conclusions regarding the underlying mechanisms of graft injury, rejection and immune regulation. Results We used a rat kidney transplantation model with strict transplant and sample preparation procedures to analyze genome wide changes in gene expression four days after syngeneic and allogeneic transplantation. Both interventions were associated with substantial changes in gene expression. After allogeneic transplantation, genes and pathways related to transport and metabolism were predominantly down-regulated consistent with rejection-mediated graft injury and dysfunction. Up-regulated genes were primarily related to the acute immune response including antigen presentation, T-cell receptor signaling, apoptosis, interferon signaling and complement cascades. We observed a cytokine and chemokine expression profile consistent with activation of a Th1-cell response. A novel finding was up-regulation of several regulatory and protective genes after allogeneic transplantation, specifically IL10, Bcl2a1, C4bpa, Ctla4, HO-1 and the SOCS family. Conclusion Our data indicate that in parallel with the predicted activation of immune response and tissue injury pathways, there is simultaneous activation of pathways for counter regulatory and protective mechanisms that would balance and limit the ongoing inflammatory/immune responses. The pathophysiological mechanisms behind and the clinical consequences of alterations in expression of these gene classes in acute rejection, injury and dysfunction vs. protection and immunoregulation, prompt further analyses and open new aspects for therapeutic approaches.

  15. Engineering broadly neutralizing antibodies for HIV prevention and therapy.

    Science.gov (United States)

    Hua, Casey K; Ackerman, Margaret E

    2016-08-01

    A combination of advances spanning from isolation to delivery of potent HIV-specific antibodies has begun to revolutionize understandings of antibody-mediated antiviral activity. As a result, the set of broadly neutralizing and highly protective antibodies has grown in number, diversity, potency, and breadth of viral recognition and neutralization. These antibodies are now being further enhanced by rational engineering of their anti-HIV activities and coupled to cutting edge gene delivery and strategies to optimize their pharmacokinetics and biodistribution. As a result, the prospects for clinical use of HIV-specific antibodies to treat, clear, and prevent HIV infection are gaining momentum. Here we discuss the diverse methods whereby antibodies are being optimized for neutralization potency and breadth, biodistribution, pharmacokinetics, and effector function with the aim of revolutionizing HIV treatment and prevention options. PMID:26827912

  16. Antibody engineering: facing new challenges in cancer therapy

    Institute of Scientific and Technical Information of China (English)

    Laura SANZ; (A)ngel M CUESTA; Marta COMPTE; Luis (A)LVAREZ-VALLINA

    2005-01-01

    Antibody-based therapeutics are beginning to realize the promise enclosed in their early denomination as "magic bullets". Initial disappointment has turned into clinical and commercial success, and engineered antibodies currently represent over 30% of biopharmaceuticals in clinical trials. Recent structural and functional data have allowed the design of a new generation of therapeutic antibodies, with strategies ranging from complement-mediated and antibody-dependant cellular cytotoxicity enhancement to improved cytotoxic payloads using toxins, drugs,radionucleids and viral delivery. This review considers the structure of different types of recombinant antibodies, their mechanism of action and how their efficacy has been increased using a broad array of approaches. We will also focus on the additional benefits offered by the use of gene therapy methods for the in vivo production of therapeutic antibodies.

  17. Systemic CD8+ T cell-mediated tumoricidal effects by intratumoral treatment of oncolytic herpes simplex virus with the agonistic monoclonal antibody for murine glucocorticoid-induced tumor necrosis factor receptor.

    Directory of Open Access Journals (Sweden)

    Mikiya Ishihara

    Full Text Available Oncolytic virotherapy combined with immunomodulators is a novel noninvasive strategy for cancer treatment. In this study, we examined the tumoricidal effects of oncolytic HF10, a naturally occurring mutant of herpes simplex virus type-1, combined with an agonistic DTA-1 monoclonal antibody specific for the glucocorticoid-induced tumor necrosis factor receptor. Two murine tumor models were used to evaluate the therapeutic efficacies of HF10 virotherapy combined with DTA-1. The kinetics and immunological mechanisms of DTA-1 in HF10 infection were examined using flow cytometry and immunohistochemistry. Intratumoral administration of HF10 in combination with DTA-1 at a low dose resulted in a more vigorous attenuation of growth of the untreated contralateral as well as the treated tumors than treatment with either HF10 or DTA-1 alone. An accumulation of CD8(+ T cells, including tumor- and herpes simplex virus type-1-specific populations, and a decrease in the number of CD4(+ Foxp3(+ T regulatory cells were seen in both HF10- and DTA-1-treated tumors. Studies using Fc-digested DTA-1 and Fcγ receptor knockout mice demonstrated the direct participation of DTA-1 in regulatory T cell depletion by antibody-dependent cellular cytotoxicity primarily via macrophages. These results indicated the potential therapeutic efficacy of a glucocorticoid-induced tumor necrosis factor receptor-specific monoclonal antibody in oncolytic virotherapy at local tumor sites.

  18. Antigen-Antibody Interaction Database (AgAbDb): a compendium of antigen-antibody interactions.

    Science.gov (United States)

    Kulkarni-Kale, Urmila; Raskar-Renuse, Snehal; Natekar-Kalantre, Girija; Saxena, Smita A

    2014-01-01

    Antigen-Antibody Interaction Database (AgAbDb) is an immunoinformatics resource developed at the Bioinformatics Centre, University of Pune, and is available online at http://bioinfo.net.in/AgAbDb.htm. Antigen-antibody interactions are a special class of protein-protein interactions that are characterized by high affinity and strict specificity of antibodies towards their antigens. Several co-crystal structures of antigen-antibody complexes have been solved and are available in the Protein Data Bank (PDB). AgAbDb is a derived knowledgebase developed with an objective to compile, curate, and analyze determinants of interactions between the respective antigen-antibody molecules. AgAbDb lists not only the residues of binding sites of antigens and antibodies, but also interacting residue pairs. It also helps in the identification of interacting residues and buried residues that constitute antibody-binding sites of protein and peptide antigens. The Antigen-Antibody Interaction Finder (AAIF), a program developed in-house, is used to compile the molecular interactions, viz. van der Waals interactions, salt bridges, and hydrogen bonds. A module for curating water-mediated interactions has also been developed. In addition, various residue-level features, viz. accessible surface area, data on epitope segment, and secondary structural state of binding site residues, are also compiled. Apart from the PDB numbering, Wu-Kabat numbering and explicit definitions of complementarity-determining regions are provided for residues of antibodies. The molecular interactions can be visualized using the program Jmol. AgAbDb can be used as a benchmark dataset to validate algorithms for prediction of B-cell epitopes. It can as well be used to improve accuracy of existing algorithms and to design new algorithms. AgAbDb can also be used to design mimotopes representing antigens as well as aid in designing processes leading to humanization of antibodies. PMID:25048123

  19. Heavy chain only antibodies

    DEFF Research Database (Denmark)

    Moghimi, Seyed Moein; Rahbarizadeh, Fatemeh; Ahmadvand, Davoud;

    2013-01-01

    Unlike conventional antibodies, heavy chain only antibodies derived from camel contain a single variable domain (VHH) and two constant domains (CH2 and CH3). Cloned and isolated VHHs possess unique properties that enable them to excel conventional therapeutic antibodies and their smaller antigen-...... for combating HER2+ breast cancer. © 2013 by Tabriz University of Medical Sciences.......Unlike conventional antibodies, heavy chain only antibodies derived from camel contain a single variable domain (VHH) and two constant domains (CH2 and CH3). Cloned and isolated VHHs possess unique properties that enable them to excel conventional therapeutic antibodies and their smaller antigen......-binding fragments in cancer targeting and therapy. VHHs express low immunogenicity, are highly robust and easy to manufacture and have the ability to recognize hidden or uncommon epitopes. We highlight the utility of VHH in design of new molecular, multifunctional particulate and immune cell-based systems...

  20. Engineering antibody therapeutics.

    Science.gov (United States)

    Chiu, Mark L; Gilliland, Gary L

    2016-06-01

    The successful introduction of antibody-based protein therapeutics into the arsenal of treatments for patients has within a few decades fostered intense innovation in the production and engineering of antibodies. Reviewed here are the methods currently used to produce antibodies along with how our knowledge of the structural and functional characterization of immunoglobulins has resulted in the engineering of antibodies to produce protein therapeutics with unique properties, both biological and biophysical, that are leading to novel therapeutic approaches. Antibody engineering includes the introduction of the antibody combining site (variable regions) into a host of architectures including bi and multi-specific formats that further impact the therapeutic properties leading to further advantages and successes in patient treatment. PMID:27525816

  1. Phosphorylcholine allows for evasion of bactericidal antibody by Haemophilus influenzae.

    Directory of Open Access Journals (Sweden)

    Sarah E Clark

    Full Text Available The human pathogen Haemophilus influenzae has the ability to quickly adapt to different host environments through phase variation of multiple structures on its lipooligosaccharide (LPS, including phosphorylcholine (ChoP. During colonization with H. influenzae, there is a selection for ChoP+ phase variants. In a murine model of nasopharyngeal colonization, this selection is lost in the absence of adaptive immunity. Based on previous data highlighting the importance of natural antibody in limiting H. influenzae colonization, the effect of ChoP expression on antibody binding and its bactericidal activity was investigated. Flow cytometric analysis revealed that ChoP+ phase variants had decreased binding of antibody to LPS epitopes compared to ChoP- phase variants. This difference in antibody binding correlated with increased survival of ChoP+ phase variants in the presence of antibody-dependent, complement-mediated killing. ChoP+ phase variants were also more resistant to trypsin digestion, suggesting a general effect on the physical properties of the outer membrane. Moreover, ChoP-mediated protection against antibody binding correlated with increased resilience of outer membrane integrity. Collectively, these data suggest that ChoP expression provides a selective advantage during colonization through ChoP-mediated effects on the accessibility of bactericidal antibody to the cell surface.

  2. Information about radiographic films rejects of dental x-rays

    International Nuclear Information System (INIS)

    The purpose of this research was to qualify and quantify the number of dental x-ray films rejected in a Porto Alegre clinic. As we analyzed the captured data, it was concluded that, our of 1066 peri-apical films, we had a total percentage of 4.5% in relation to the total of the exams made. This 4.5% consists of the following rejects: placement, patient movement, technical errors, diaphragm, too much clarity in the result, double exposure, prolongation, shortness, darkened for not have been shot, superposed film. Because of that, the rejection, due to the bad placement of the film, is the one with the larger percentage value, i.e., 1.22% of the 4.5%. With the knowledge of the types of rejects and their causes, it was possible to correct some sources of systematic errors minimizing the repetition of the exams, saving costs, time and diminishing the ionizing radiation exposure for the patient, odontologist and his technical staff, which will be proved. (authors). 4 refs., 1 tab

  3. Peer Rejection Cues Induce Cardiac Slowing after Transition into Adolescence

    Science.gov (United States)

    Gunther Moor, Bregtje; Bos, Marieke G. N.; Crone, Eveline A.; van der Molen, Maurits W.

    2014-01-01

    The present study examined developmental and gender differences in sensitivity to peer rejection across the transition into adolescence by examining beat-by-beat heart rate responses. Children between the ages of 8 and 14 years were presented with unfamiliar faces of age-matched peers and were asked to predict whether they would be liked by the…

  4. Examining Appearance-Based Rejection Sensitivity during Early Adolescence

    Science.gov (United States)

    Bowker, Julie C.; Thomas, Katelyn K.; Spencer, Sarah V.; Park, Lora E.

    2013-01-01

    The present study of 150 adolescents ("M" age = 13.05 years) examined the associations between appearance-based rejection sensitivity (Appearance-RS) and psychological adjustment during early adolescence, and evaluated three types of other-gender peer experiences (other-gender friendship, peer acceptance, and romantic relationships) as…

  5. Duke power cities training, electrodes for low weld reject rate

    International Nuclear Information System (INIS)

    An intensive training program has allowed Duke Power Co. to achieve a reject rate of less than 1% in pipe and plate welds at its giant Catawba Nuclear Power Station, 30 miles southwest of Charlotte, NC. Constructed on a 418 acre site, the Catawba Station is scheduled to furnish 2240 megawatts of electricity from two reactors. Completion is set for 1983, and Duke will use around 208,000 lb (94,000 kg) of welding electrodes a year to complete the job. The reject rate on welding Schedule 40 pipe from 1 to 34 in. (2.5-86.4 cm) in diameter is 0.6%, and on carbon steel plate up to 3 in. (7.6 cm) thick the reject rate is 0.7%. In both instances the electrodes used are 0.045 in. (1.14 mm) Dual Shield 7000 (AWS E70T-1) and iron powder low hydrogen Atom Arc (AWS E7018). ''Intensive welder training no doubt has achieved such a high degree of success in low reject rates on our nuclear specification welds, but the welder must also have an electrode that has a certain amount of built-in ''forgiveness'' in the event of human oversight.''

  6. 48 CFR 619.505 - Rejecting Small Business Administration recommendations.

    Science.gov (United States)

    2010-10-01

    ... Small Business Administration recommendations. The Procurement Executive is the agency head for the... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Rejecting Small Business Administration recommendations. 619.505 Section 619.505 Federal Acquisition Regulations System DEPARTMENT...

  7. 48 CFR 1319.505 - Rejecting Small Business Administration recommendations.

    Science.gov (United States)

    2010-10-01

    ... Small Business Administration recommendations. (a) The designee authorized to render a decision on the Small Business Administration's appeal of the contracting officer's decision is set forth in CAM 1301.70... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Rejecting Small...

  8. Compact filtering monopole patch antenna with dual-band rejection.

    Science.gov (United States)

    Kim, Sun-Woong; Choi, Dong-You

    2016-01-01

    In this paper, a compact ultra-wideband patch antenna with dual-band rejection is proposed. The proposed antenna filters 3.3-3.8 GHz WiMAX and 5.15-5.85 GHz WLAN by respectively rejecting these bands through a C-shaped slit and a λg/4 resonator. The λg/4 resonator is positioned as a pair, centered around the microstrip line, and a C-type slit is inserted into an elliptical patch. The impedance bandwidth of the proposed antenna is 2.9-9.3 GHz, which satisfies the bandwidth for ultra-wideband communication systems. Further, the proposed antenna provides dual-band rejection at two bands: 3.2-3.85 and 4.7-6.03 GHz. The radiation pattern of the antenna is omnidirectional, and antenna gain is maintained constantly while showing -8.4 and -1.5 dBi at the two rejected bands, respectively. PMID:27386331

  9. Nucleic Acid Drugs for Prevention of Cardiac Rejection

    Directory of Open Access Journals (Sweden)

    Jun-ichi Suzuki

    2009-01-01

    Full Text Available Heart transplantation has been broadly performed in humans. However, occurrence of acute and chronic rejection has not yet been resolved. Several inflammatory factors, such as cytokines and adhesion molecules, enhance the rejection. The graft arterial disease (GAD, which is a type of chronic rejection, is characterized by intimal thickening comprised of proliferative smooth muscle cells. Specific treatments that target the attenuation of acute rejection and GAD formation have not been well studied in cardiac transplantation. Recent progress in the nucleic acid drugs, such as antisense oligodeoxynucleotides (ODNs to regulate the transcription of disease-related genes, has important roles in therapeutic applications. Transfection of cis-element double-stranded DNA, named as “decoy,” has been also reported to be a useful nucleic acid drug. This decoy strategy has been not only a useful method for the experimental studies of gene regulation but also a novel clinical strategy. In this paper, we reviewed the experimental results of NF-κB, E2F, AP-1, and STAT-1 decoy and other ODNs using the experimental heart transplant models.

  10. Compact filtering monopole patch antenna with dual-band rejection.

    Science.gov (United States)

    Kim, Sun-Woong; Choi, Dong-You

    2016-01-01

    In this paper, a compact ultra-wideband patch antenna with dual-band rejection is proposed. The proposed antenna filters 3.3-3.8 GHz WiMAX and 5.15-5.85 GHz WLAN by respectively rejecting these bands through a C-shaped slit and a λg/4 resonator. The λg/4 resonator is positioned as a pair, centered around the microstrip line, and a C-type slit is inserted into an elliptical patch. The impedance bandwidth of the proposed antenna is 2.9-9.3 GHz, which satisfies the bandwidth for ultra-wideband communication systems. Further, the proposed antenna provides dual-band rejection at two bands: 3.2-3.85 and 4.7-6.03 GHz. The radiation pattern of the antenna is omnidirectional, and antenna gain is maintained constantly while showing -8.4 and -1.5 dBi at the two rejected bands, respectively.

  11. Rejected Manuscripts in Publishers' Archives: Legal Rights and Access

    Science.gov (United States)

    Hamburger, Susan

    2011-01-01

    This article focuses on an analysis of how various archival repositories deal with rejected manuscripts in publishers' archives as part of existing collections and as potential donations, and includes suggestions for ways to provide access while maintaining the author's legal rights. Viewpoints from the journal editor, author, archivist, and…

  12. Diffusion-based outlier rejection for underwater navigation

    DEFF Research Database (Denmark)

    Vike, Steinar; Jouffroy, Jerome

    This paper addresses the issue of rejecting spurious acoustic position measurements for the estimation of trajectories in underwater vehicle navigation. The method relies on the diffusion-based observer approach (Jouffroy and Opderbecke, 2004; 2005), which allows one to consider and process entire...

  13. Rejection of false saturation data in optical pulse-oximeter

    Science.gov (United States)

    Scalise, Lorenzo; Marchionni, Paolo; Carnielli, Virgilio

    2010-04-01

    Pulse oximetry (PO) is a non-invasive medical device used for monitoring of the arterial oxygen saturation (SaO2) and in particular of haemoglobin oxygenation in blood. Oxygen saturation is commonly used in any setting where the patient blood oxygen saturation is unstable, including Neonatal Intensive Care Unit (NICU). The main factor affecting PO's output data is the presence of voluntary or involuntary motion artifacts or imperfect skin-sensor contact. Various methods have been employed to reject motion artifact but have met with little success. The aim of the present work is to propose a novel measurement procedure for real-time monitoring and validation of the oxygen saturation data as measured in standard pulse oxymeter. The procedure should be able to individuate and reject erroneous saturation data due to incorrect transducer-skin contact or motion artifact. In the case of short sequences of rejected SpO2 data (time durationoximeter (HRSAT) and the SpO2 value. In order to remove the erroneous SpO2 values reported in the rough data in coincidence of motion artifact (top, right), we have implemented a specific algorithm which provides at the output a new sequence of SpO2 data (validated SpO2 data). With the aim to "rescue" SpO2 value rejected by the previously presented algorithm, we have implemented an algorithm able to provide the "most-probable" SpO2 values in the case of single rejected values or in the case of short sequences of invalidated data (oximeter are not validated by the use of our method (corresponding to a total time of 16 hr, 8min and 40s). The use of the proposed algorithm aiming to "rescue" data from short sequences of rejected data (< 8s) allows to increase the validated data of the 2.5%t(equivalent to 8hr, 40 min and 16s), allowing a percent of usable data of the 95.7%. Once implemented in clinic, it could be used to identify the period of the day in which the percent of rejected data increase or correlate this data to clinical procedure

  14. Fate of Manuscripts Rejected From the Red Journal

    International Nuclear Information System (INIS)

    Purpose: To evaluate characteristics associated with higher rates of acceptance for original manuscripts submitted for publication to the International Journal of Radiation Oncology • Biology • Physics (IJROBP) and describe the fate of rejected manuscripts. Methods and Materials: Manuscripts submitted to the IJROBP from May 1, 2010, to August 31, 2010, and May 1, 2012, to August 31, 2012, were evaluated for author demographics and acceptance status. A PubMed search was performed for each IJROBP-rejected manuscript to ascertain whether the manuscript was ultimately published elsewhere. The Impact Factor of the accepting journal and the number of citations of the published manuscript were also collected. Results: Of the 500 included manuscripts, 172 (34.4%) were accepted and 328 (65.6%) were rejected. There was no significant difference in acceptance rates according to gender or degree of the submitting author, but there were significant differences seen based on the submitting author's country, rank, and h-index. On multivariate analysis, earlier year submitted (P<.0001) and higher author h-index (P=.006) remained significantly associated with acceptance into the IJROBP. Two hundred thirty-five IJROBP-rejected manuscripts (71.7%) were ultimately published in a PubMed-listed journal as of July 2014. There were no significant differences in any submitting author characteristics. Journals accepting IJROBP-rejected manuscripts had a lower median [interquartile range] 2013 impact factor compared with the IJROBP (2.45 [1.53-3.71] vs 4.176). The IJROBP-rejected manuscripts ultimately published elsewhere had a lower median [interquartile range] number of citations (1 [0-4] vs 6 [2-11]; P<.001), which persisted on multivariate analysis. Conclusions: The acceptance rate for manuscripts submitted to the IJROBP is approximately one-third, and approximately 70% of rejected manuscripts are ultimately published in other PubMed-listed journals, but these ultimate

  15. Fate of Manuscripts Rejected From the Red Journal

    Energy Technology Data Exchange (ETDEWEB)

    Holliday, Emma B., E-mail: emmaholliday@gmail.com [Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Yang, George [The University of South Florida Morsani College of Medicine, Tampa, Florida (United States); Jagsi, Reshma [Department of Radiation Oncology, The University of Michigan, Ann Arbor, Michigan (United States); Hoffman, Karen E. [Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Bennett, Katherine Egan; Grace, Calley [Scientific Publications, American Society for Radiation Oncology, Fairfax, Virginia (United States); Zietman, Anthony L. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)

    2015-01-01

    Purpose: To evaluate characteristics associated with higher rates of acceptance for original manuscripts submitted for publication to the International Journal of Radiation Oncology • Biology • Physics (IJROBP) and describe the fate of rejected manuscripts. Methods and Materials: Manuscripts submitted to the IJROBP from May 1, 2010, to August 31, 2010, and May 1, 2012, to August 31, 2012, were evaluated for author demographics and acceptance status. A PubMed search was performed for each IJROBP-rejected manuscript to ascertain whether the manuscript was ultimately published elsewhere. The Impact Factor of the accepting journal and the number of citations of the published manuscript were also collected. Results: Of the 500 included manuscripts, 172 (34.4%) were accepted and 328 (65.6%) were rejected. There was no significant difference in acceptance rates according to gender or degree of the submitting author, but there were significant differences seen based on the submitting author's country, rank, and h-index. On multivariate analysis, earlier year submitted (P<.0001) and higher author h-index (P=.006) remained significantly associated with acceptance into the IJROBP. Two hundred thirty-five IJROBP-rejected manuscripts (71.7%) were ultimately published in a PubMed-listed journal as of July 2014. There were no significant differences in any submitting author characteristics. Journals accepting IJROBP-rejected manuscripts had a lower median [interquartile range] 2013 impact factor compared with the IJROBP (2.45 [1.53-3.71] vs 4.176). The IJROBP-rejected manuscripts ultimately published elsewhere had a lower median [interquartile range] number of citations (1 [0-4] vs 6 [2-11]; P<.001), which persisted on multivariate analysis. Conclusions: The acceptance rate for manuscripts submitted to the IJROBP is approximately one-third, and approximately 70% of rejected manuscripts are ultimately published in other PubMed-listed journals, but these ultimate

  16. Perceived childhood paternal acceptance-rejection among adults

    International Nuclear Information System (INIS)

    Objective: To determine the childhood perceptual difference of paternal acceptance-rejection between those having psychological disorders and non-clinical population during adulthood. Study Design: Comparative study. Place and Duration of Study: Karwan-e-Hayat, Psychiatric Care and Rehabilitation Centre, Keamari, Karachi, Pakistan, from January to August 2011. Methodology: To test our hypotheses, 69 participants were selected from Karwan-e-Hayat Psychiatric Care and Rehabilitation Centre, Karachi on the basis of purposive sampling technique and 79 from Karachi city on the basis of convenient sampling technique. To measure their perceived paternal acceptance-rejection during childhood, Adult Parental acceptance-rejection questionnaire (PARQ)/control: father-short form (Urdu translation) was administered. The statistical analysis of data was done with the predictive analytics software (PASW). Results: One hundred and forty eight (78 males and 70 females) participants with mean age of 31.28 +- 9.54 years were included. Out of them 69 (40 males and 29 females) were clinical cases of depression, mania and psychosis with mean age of 33.26 +- 9.51 years. Seventy nine (38 males and 41 females) were normal individuals with mean age of 29.54 +- 9.29 years of the demographics corresponding to the clinical population. Independent t-test revealed a significant difference in perceived childhood father acceptance-rejection between clinical and non-clinical population (p < 0.05) and significant gender difference (p < 0.05). Conclusion: The studied clinical population and male participants perceived to be more rejected by their father during their childhood than non-clinical population and female participants. (author)

  17. Vicarious group-based rejection: creating a potentially dangerous mix of humiliation, powerlessness, and anger.

    Directory of Open Access Journals (Sweden)

    Tinka M Veldhuis

    Full Text Available Rejection can convey that one is seen as inferior and not worth bothering with. Is it possible for people to feel vicariously rejected in this sense and have reactions that are similar to those following personal rejection, such as feeling humiliated, powerless, and angry? A study on personal rejection was followed by two main studies on vicarious group-based rejection. It was found that merely observing rejection of ingroup members can trigger feelings of humiliation that are equally intense as those experienced in response to personal rejection. Moreover, given that the rejection is explicit, vicariously experienced feelings of humiliation can be accompanied by powerlessness and anger. Potentially, this combination of emotions could be an important source of offensive action against rejecters.

  18. Plasma cell-rich acute rejection of the renal allograft: A distinctive morphologic form of acute rejection?

    Science.gov (United States)

    Gupta, R; Sharma, A; Mahanta, P J; Agarwal, S K; Dinda, A K

    2012-05-01

    This study was aimed at evaluating the clinicopathologic features of plasma cell-rich acute rejection (PCAR) of renal allograft and comparing them with acute cellular rejection (ACR), non-plasma cell-rich type. During a 2-year period, eight renal allograft biopsies were diagnosed as PCAR (plasma cells >10% of interstitial infiltrate). For comparison, 14 biopsies with ACR were included in the study. Detailed pretransplant data, serum creatinine at presentation, and other clinical features of all these cases were noted. Renal biopsy slides were reviewed and relevant immunohistochemistry performed for characterization of plasma cell infiltrate. The age range and duration of transplantation to diagnosis of acute rejection were comparable in both the groups. Histologically, the proportion of interstitial plasma cells, mean interstitial inflammation, and tubulitis score were higher in the PCAR group compared with cases with ACR. A significant difference was found in the outcome at last follow-up, being worse in patients with PCAR. This study shows that PCAR portends a poor outcome compared with ACR, with comparable Banff grade of rejection. Due to its rarity and recent description, nephrologists and renal pathologists need to be aware of this entity.

  19. TU-100 (Daikenchuto and ginger ameliorate anti-CD3 antibody induced T cell-mediated murine enteritis: microbe-independent effects involving Akt and NF-κB suppression.

    Directory of Open Access Journals (Sweden)

    Nobuhiro Ueno

    Full Text Available The Japanese traditional medicine daikenchuto (TU-100 has anti-inflammatory activities, but the mechanisms remain incompletely understood. TU-100 includes ginger, ginseng, and Japanese pepper, each component possessing bioactive properties. The effects of TU-100 and individual components were investigated in a model of intestinal T lymphocyte activation using anti-CD3 antibody. To determine contribution of intestinal bacteria, specific pathogen free (SPF and germ free (GF mice were used. TU-100 or its components were delivered by diet or by gavage. Anti-CD3 antibody increased jejunal accumulation of fluid, increased TNFα, and induced intestinal epithelial apoptosis in both SPF and GF mice, which was blocked by either TU-100 or ginger, but not by ginseng or Japanese pepper. TU-100 and ginger also blocked anti-CD3-stimulated Akt and NF-κB activation. A co-culture system of colonic Caco2BBE and Jurkat-1 cells was used to examine T-lymphocyte/epithelial cells interactions. Jurkat-1 cells were stimulated with anti-CD3 to produce TNFα that activates epithelial cell NF-κB. TU-100 and ginger blocked anti-CD3 antibody activation of Akt in Jurkat cells, decreasing their TNFα production. Additionally, TU-100 and ginger alone blocked direct TNFα stimulation of Caco2BBE cells and decreased activation of caspase-3 and polyADP ribose. The present studies demonstrate a new anti-inflammatory action of TU-100 that is microbe-independent and due to its ginger component.

  20. The Neural Basis of Recollection Rejection: Increases in Hippocampal-Prefrontal Connectivity in the Absence of a Shared Recall-to-Reject and Target Recollection Network.

    Science.gov (United States)

    Bowman, Caitlin R; Dennis, Nancy A

    2016-08-01

    Recollection rejection or "recall-to-reject" is a mechanism that has been posited to help maintain accurate memory by preventing the occurrence of false memories. Recollection rejection occurs when the presentation of a new item during recognition triggers recall of an associated target, a mismatch in features between the new and old items is registered, and the lure is correctly rejected. Critically, this characterization of recollection rejection involves a recall signal that is conceptually similar to recollection as elicited by a target. However, previous neuroimaging studies have not evaluated the extent to which recollection rejection and target recollection rely on a common neural signal but have instead focused on recollection rejection as a postretrieval monitoring process. This study utilized a false memory paradigm in conjunction with an adapted remember-know-new response paradigm that separated "new" responses based on recollection rejection from those that were based on a lack of familiarity with the item. This procedure allowed for parallel recollection rejection and target recollection contrasts to be computed. Results revealed that, contrary to predictions from theoretical and behavioral literature, there was virtually no evidence of a common retrieval mechanism supporting recollection rejection and target recollection. Instead of the typical target recollection network, recollection rejection recruited a network of lateral prefrontal and bilateral parietal regions that is consistent with the retrieval monitoring network identified in previous neuroimaging studies of recollection rejection. However, a functional connectivity analysis revealed a component of the frontoparietal rejection network that showed increased coupling with the right hippocampus during recollection rejection responses. As such, we demonstrate a possible link between PFC monitoring network and basic retrieval mechanisms within the hippocampus that was not revealed with