Search results for "raft"

Polymorphism in the immunoglobulin-like domains of the receptor tyrosine kinase from the sponge Geodia cydonium.

1996

Sponges [Porifera] are the phylogenetically oldest phylum of the Metazoa. They are provided with both cellular and humoral allorecognition systems. The underlying molecules are not yet known. To study allorecognition in sponges we first determined the frequency of graft rejection in a natural population of the marine sponge Geodia cydonium. We then determined, for the first time at the molecular level, the degree of sequence polymorphism in segments of one molecule which may be related to sponge allorecognition and host defense: the Ig-like domains from the receptor tyrosine kinase [RTK]. Thirty six pairs of auto- and allografts were assayed, either by parabiotic attachment or insertion of …

Suppression of allograft rejection in the sponge Suberites domuncula by FK506 and expression of genes encoding FK506-binding proteins in allografts.

2001

SUMMARY Porifera (sponges) are, evolutionarily, the oldest metazoan phylum. Recent molecular data suggest that these animals possess molecules similar to and homologous with those of the innate and adaptive immune systems of higher Metazoa. Applying the biological system of parabiosis and the technique of differential display of mRNA, two cDNAs encoding putative FK506-binding proteins were isolated. FK506 is successfully used in clinics as a drug to prevent allograft rejection and is toxic to Suberites domuncula cells in vitro at doses above 100ng ml−1. Autograft fusion of transplants from S. domuncula was not affected by FK506. Allograft non-fusion was not affected by FK506 at toxic doses;…

Clinical Predictors of Immunotolerance in Heart Transplantation

2010

Abstract Background and Aim The drugs routinely administered to prevent rejection often cause lethal side effects. Tolerant patients, therefore, should be identified to minimize these problems. The aim of this analysis was to identify clinical variables that may be associated with tolerance. Methods We recruited 522 heart transplants (HT), excluding combined procedures, retransplantations, pediatric recipients, and subjects who died in the first year to obtain a cohort of 375 patients. Two groups were distinguished by the presence of echocardiographic, clinical, or pathological evidence of rejection in the first year (15 echocardiograms and 10 protocol biopsies per patient); 99 tolerant pat…

Protective role of the complement regulatory protein human CD-55 in cardiac xenograft: a descriptive study and a revision of the literature.

2002

The limited and inadequate availability of organs from human donors has resulted in the utilisation of xenografts as an alternative tool. Nevertheless, hyperacute rejection (HAR) following xenograft determines the loss of the transplanted organ. The “primum movens” is the activation of the complement pathway mediated by the binding of natural xenogenic antibodies to the endothelium of the graft, followed by the lysis of the endothelial cells with subsequent oedema, thrombosis and necrosis of the transplanted organ. In this work we describe morphological and biomolecular observations of isolated human-decay accelerating factor (h-DAF, CD55) transgenic pig hearts, after perfusion for four hou…

Differential diagnosis of cytomegalovirus infection and acute rejection by serum CC-Chemokine measurement after orthotopic liver transplantation

2003

Leflunomide (HWA 486), a novel immunomodulating compound for the treatment of autoimmune disorders and reactions leading to transplantation rejection.

1991

Leflunomide has been shown to be very effective in preventing and curing several autoimmune animal diseases. Further, this agent is as effective as cyclosporin A in preventing the rejection of skin and kidney transplants in rats. Preliminary results from patients suffering from severe cases of rheumatoid arthritis demonstrated that clinical and immunological parameters could be improved with leflunomide therapy. Mode of action studies revealed that this substance antagonizes the proliferation inducing activity of several cytokines and is cytostatic for certain cell types. In this light, we could show that tyrosine phosphorylation of the RR-SRC peptide substrate and the autophosphorylation o…

Increased expression of the potential proapoptotic molecule DD2 and increased synthesis of leukotriene B4 during allograft rejection in a marine spon…

2000

Sponges (Porifera) are a classical model to study the events during tissue transplantation. Applying the 'insertion technique' autografts from the marine sponge Geodia cydonium fuse within 5 days. In contrast, allografts are rejected and destroyed. Here we show that during allograft rejection the cells in the grafts undergo apoptosis; 5 days after transplantation 46% of the cells show signs of apoptosis. In a previous study it was shown that during this process a tumor necrosis factor-like molecule is induced in allo- and xenografts. Molecules grouped to the superfamily of tumor necrosis factor receptors and a series of associated adapter molecules contain the characteristic death domain. T…

GM-CSF restores innate, but not adaptive, immune responses in glucocorticoid-immunosuppressed human blood in vitro.

2003

Abstract Infection remains the major complication of immunosuppressive therapy in organ transplantation. Therefore, reconstitution of the innate immunity against infections, without activation of the adaptive immune responses, to prevent graft rejection is a clinically desirable status in transplant recipients. We found that GM-CSF restored TNF mRNA and protein expression without inducing IL-2 production and T cell proliferation in glucocorticoid-immunosuppressed blood from either healthy donors or liver transplant patients. Gene array experiments indicated that GM-CSF selectively restored a variety of dexamethasone-suppressed, LPS-inducible genes relevant for innate immunity. A possible ex…

Patient outcomes in two steroid-free regimens using tacrolimus monotherapy after daclizumab induction and tacrolimus with mycophenolate mofetil in li…

2008

Introduction. Long-term steroid administration may predispose liver transplant recipients to infectious and metabolic complication. Maintaining effective immunoprophylaxis while minimizing the negative consequences of steroid therapy could be a key factor in improving clinical outcomes.Methods. Six hundred two patients were randomized to receive tacrolimus (TAC) immunosuppression with a single-steroid bolus and two doses of daclizumab (DAC) or mycophenolate mofetil (MMF).Results. The incidence of biopsy-proven acute rejection was 19.7% in the TAC/DAC group and 16.2% in the TAC/ MMF group (ns). Three-month patient and graft survival were similar. Steroid use at month-3 was low at 5.5% in the…

14th International HLA and Immunogenetics Workshop: Report on the Prospective Chronic Rejection Project

2007

An international collaborative study of 45 transplant centers was undertaken at the 14th International HLA (human leukocyte antigen) and Immunogenetics Workshop to see if HLA antibodies detected posttransplant are predictive of chronic graft failure. With the newly developed assay, MICA (major histocompatibility complex class I-related chain A) antibodies were also measured and their effect analyzed. Total of 5219 sera from patients who were more than 6 months posttransplant with functioning graft were tested for HLA antibodies by enzyme-linked immunosorbent assay, flow cytometry, or Luminex. HLA antibodies were found in 27.2% of kidney patients, 23.6% in the liver, 52.7% in the heart, and …