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Lin F, Kaminski HJ, Conti-Fine BM, Wang W, Richmonds C, Medof ME. Markedly enhanced susceptibility to experimental autoimmune myasthenia gravis in the absence of decay-accelerating factor protection. J Clin Invest 2002; 110:1269-74. [PMID: 12417565 PMCID: PMC151616 DOI: 10.1172/jci16086] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Myasthenia gravis (MG) is an autoimmune neuromuscular transmission disorder characterized by loss of acetylcholine receptors (AChR's) due primarily to the production of anti-AChR autoantibodies. In this study we investigated whether the presence of decay-accelerating factor (DAF or CD55), an intrinsic complement regulator, protects against the development of disease. Experimental autoimmune MG was induced in Daf1(-/-) mice (devoid of neuromuscular DAF protein) and their Daf1(+/+) littermates by injection of rat anti-AChR mAb McAb-3. After twenty-four hours, grip strength assessment revealed that Daf1(-/-) mice exhibited hold times of less than 30 seconds, compared with more than 8 minutes for the Daf1(+/+) controls. The weakness was reversed by edrophonium, consistent with a myasthenic disorder. Immunohistochemistry revealed greatly augmented C3b deposition localized at postsynaptic junctions, and radioimmunoassays showed more profound reductions in AChR levels. Electron microscopy demonstrated markedly greater junctional damage in the Daf1(-/-) mice compared with the Daf1(+/+) littermates. Control studies showed equivalent levels of other cell surface regulators, i.e., Crry and CD59. The results demonstrate that mice that lack DAF are markedly more susceptible to anti-AChR-induced MG, which simulates the primary mechanism in the human disease, and strongly suggest that in disease flares complement inhibitors might have therapeutic value.
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Mason JC, Ahmed Z, Mankoff R, Lidington EA, Ahmad S, Bhatia V, Kinderlerer A, Randi AM, Haskard DO. Statin-induced expression of decay-accelerating factor protects vascular endothelium against complement-mediated injury. Circ Res 2002; 91:696-703. [PMID: 12386146 DOI: 10.1161/01.res.0000038151.57577.19] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Complement-mediated vascular injury is important in the pathophysiology of atherosclerosis and myocardial infarction. Because recent evidence shows that statins have beneficial effects on endothelial cell (EC) function independent of lipid lowering, we explored the hypothesis that statins modulate vascular EC resistance to complement through the upregulation of complement-inhibitory proteins. Human umbilical vein and aortic ECs were treated with atorvastatin or simvastatin, and decay-accelerating factor (DAF), membrane cofactor protein, and CD59 expression was measured by flow cytometry. A dose-dependent increase in DAF expression of up to 4-fold was seen 24 to 48 hours after treatment. Statin-induced upregulation of DAF required increased steady-state mRNA and de novo protein synthesis. L-Mevalonate and geranylgeranyl pyrophosphate reversed the effect, confirming the role of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibition and suggesting that constitutive DAF expression is negatively regulated by geranylgeranylation. Neither farnesyl pyrophosphate nor squalene inhibited statin-induced DAF expression, suggesting that the effect is independent of cholesterol lowering. Statin-induced DAF upregulation was mediated by the activation of protein kinase Calpha and inhibition of RhoA and was independent of phosphatidylinositol-3 kinase and NO activity. The increased DAF expression was functionally effective, resulting in significant reduction of C3 deposition and complement-mediated lysis of antibody-coated ECs. These observations provide evidence for a novel cytoprotective action of statins on vascular endothelium that is independent of the effect on lipids and results in enhanced protection against complement-mediated injury. Modulation of complement regulatory protein expression may contribute to the early beneficial effects of statins in reducing the morbidity and mortality associated with atherosclerosis.
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Miwa T, Maldonado MA, Zhou L, Sun X, Luo HY, Cai D, Werth VP, Madaio MP, Eisenberg RA, Song WC. Deletion of decay-accelerating factor (CD55) exacerbates autoimmune disease development in MRL/lpr mice. THE AMERICAN JOURNAL OF PATHOLOGY 2002; 161:1077-86. [PMID: 12213736 PMCID: PMC1867258 DOI: 10.1016/s0002-9440(10)64268-x] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Decay-accelerating factor (DAF, CD55) is a glycosylphosphatidylinositol-anchored membrane protein that restricts complement activation on autologous cells. It is also a ligand for CD97, an activation-associated lymphocyte antigen with seven transmembrane domains. It is widely expressed on cells of both the hematopoietic and nonhematopoietic lineages. Although deficiency of DAF on human erythrocytes is associated with the hemolytic anemia syndrome paroxysmal nocturnal hemoglobinuria, the in vivo biology of DAF is still poorly understood. We addressed the in vivo function of DAF in a knockout mouse model and describe here that deletion of DAF exacerbates autoimmune disease development in MRL/lpr mice, a model for human systemic lupus erythematosus. Compared to DAF-sufficient littermate controls, DAF-deficient female MRL/lpr mice developed exacerbated lymphadenopathy and splenomegaly, higher serum anti-chromatin autoantibody levels, and aggravated dermatitis. Consistent with the phenotype of aggravated dermatitis in DAF-deficient mice, Northern and Western blots and immunofluorescence studies showed DAF to be expressed abundantly in the mouse skin, suggesting that it may play a particularly important role in this tissue. Histology and immunostaining demonstrated inflammatory infiltrate and focal C3 deposition in early skin lesions, mostly along the dermal-epidermal junction. These results reveal a protective function of DAF in the development of a systemic autoimmune syndrome and suggest that dysfunction or down-regulation of DAF may contribute to autoimmune disease pathogenesis and manifestation.
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Miwa T, Zhou L, Hilliard B, Molina H, Song WC. Crry, but not CD59 and DAF, is indispensable for murine erythrocyte protection in vivo from spontaneous complement attack. Blood 2002; 99:3707-16. [PMID: 11986227 DOI: 10.1182/blood.v99.10.3707] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Decay-accelerating factor (DAF) and CD59 are 2 glycosylphosphatidylinositol-anchored membrane proteins that inhibit complement activation at the C3 and C5b-9 step, respectively. CD59 is considered critical for protecting erythrocytes from spontaneous complement attack, as deficiency of CD59 or CD59/DAF, but not of DAF alone, on human erythrocytes renders them sensitive to complement lysis in paroxysmal nocturnal hemoglobinuria syndrome. To evaluate the relative roles of CD59 and DAF in vivo, we have generated and studied a CD59 knockout and a CD59/DAF double-knockout mouse. CD59-deficient and CD59/DAF-double-deficient mouse erythrocytes were highly sensitive to antibody-induced complement lysis in vitro, yet neither CD59 knockout nor CD59/DAF double-knockout mouse developed spontaneous hemolytic anemia. Consistent with the latter observation, erythrocytes from the 2 strains of mutant mice were shown to have a normal lifespan in vivo. In contrast, mouse erythrocytes deficient in complement receptor 1 (CR1)-related gene y (Crry), a membrane C3 inhibitor with DAF and membrane cofactor protein activities, were rapidly eliminated from the circulation by a complement-dependent mechanism. Compared with DAF-deficient erythrocytes, Crry-deficient erythrocytes incurred higher levels of spontaneous C3 deposition in vivo. These findings demonstrate that CD59 and DAF are not indispensable on murine erythrocytes. Rather, effective C3 regulation on the cell surface, provided by Crry rather than DAF, is necessary for mouse erythrocytes to resist spontaneous complement attack. Our results raise the possibility that proper control of C3 activation may also be critical on human erythrocytes, where CR1 but not DAF could be the principal regulator of spontaneous C3 activation.
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Lin F, Emancipator SN, Salant DJ, Medof ME. Decay-accelerating factor confers protection against complement-mediated podocyte injury in acute nephrotoxic nephritis. J Transl Med 2002; 82:563-9. [PMID: 12003997 DOI: 10.1038/labinvest.3780451] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
SUMMARY Decay-accelerating factor (DAF or CD55) is one of a set of regulators that function to protect self cells from deposition of autologous C3b on their surfaces. Its relative importance in vivo, however, is incompletely understood. As one approach to address this issue, we induced nephrotoxic serum (NTS) nephritis in wild-type mice and Daf1 gene-floxed mice devoid of renal DAF expression. For these experiments NTS IgG was administered at a dose (0.5 mg iv) that requires complement for glomerular injury. After 18 hours, renal injury was assessed by proteinuria and by histologic, immunohistochemical, and electron microscopic analyses of kidneys. Fifteen normal and 15 DAF-deficient mice were studied. Baseline albuminuria in the Daf1(-/-) mice was 115.9 +/- 41.4 microg/mg creatinine as compared with 85.7 +/- 32.3 microg/mg creatinine in their Daf1(+/+) littermates (p = 0.075). After administration of NTS IgG, albuminuria increased to 2001.7 +/- 688.7 microg/mg creatinine as compared with 799.7 +/- 340.5 microg/mg creatinine in the controls (p = 0.0003). Glomerular histology was similar in Daf1(-/-) and Daf1(+/+) mice, with essentially no infiltrating leukocytes. In contrast, electron microscopy revealed severe podocyte fusion in the Daf1(-/-) mice but only mild focal changes in the controls. Immunohistochemical staining showed equivalent deposition of the administered (sheep) NTS IgG in the Daf1(-/-) and Daf1(+/+) animals. This contrasted with marked deposition of autologous murine C3 in the former and minimal deposition in the latter. The results show that DAF is essential physiologically for protecting glomeruli against autologous complement attack initiated by the classical pathway.
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Schuurman HJ, Pino-Chavez G, Phillips MJ, Thomas L, White DJG, Cozzi E. Incidence of hyperacute rejection in pig-to-primate transplantation using organs from hDAF-transgenic donors. Transplantation 2002; 73:1146-51. [PMID: 11965048 DOI: 10.1097/00007890-200204150-00024] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Cynomolgus monkeys or baboons received under immunosuppression kidney or heart grafts from pigs transgenic for human decay-accelerating factor (hDAF) or from control pigs. Hyperacute rejection (HAR) is often difficult to differentiate from nonimmunological causes of organ or recipient dysfunction (NIC), and therefore, a thorough pathology review of all cases with 0-4 days survival (inclusive) was conducted. METHODS Pathology slides were blinded and together with limited clinical data reviewed by two pathologists. After unblinding, data were compared with the original diagnosis made during the course of the program, and a final diagnosis was reached considering the complete clinical dataset. RESULTS Life-supporting kidney transplantation was performed in 245 cynomolgus monkeys (234 hDAF, 11 controls), of which 102 cases had 0-4 day survival. None of the hDAF cases showed HAR, whereas this occurred in 27% of controls (P<10-6). Heterotopic heart transplantation was performed in 65 monkeys (57 hDAF, 8 controls), of which 41 cases had 0-4 day survival. HAR was observed in 7% of hDAF cases and in 57% of controls (P=0.002). Heterotopic heart transplantation in baboons was performed in 33 animals (28 hDAF, 5 controls), of which 15 cases had 0-4 day survival. HAR was observed in 11% of hDAF cases and in 20% of controls. Sixteen baboons were subjected to orthotopic heart transplantation, all from hDAF donors, out of which eight survived 0-4 days. The incidence of HAR was 6%. CONCLUSIONS In the largest series of pig-to-primate solid organ transplants performed thus far, the presence of the hDAF transgene fully prevents HAR of cynomolgus monkey kidney transplants and partially inhibits HAR of heart grafts in cynomolgus monkeys or baboons. The incidence of HAR in control grafts is significantly higher.
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Boulday G, Hamann J, Soulillou JP, Charreau B. CD97-decay-accelerating factor interaction is not involved in leukocyte adhesion to endothelial cells. Transplantation 2002; 73:429-36. [PMID: 11884941 DOI: 10.1097/00007890-200202150-00018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Effective improvement in xenograft survival is achieved using transplants from transgenic pigs expressing human complement (C) regulatory proteins, including decay-accelerating factor (DAF), CD59, and CD46 on endothelial cells (ECs). The aim of this study was to investigate whether human DAF expression in porcine ECs, as well as regulating C activation, can modify intercellular events through its interaction with its receptor, CD97, on human leukocytes. METHODS Cellular interactions between human leukocytes and porcine ECs were investigated in vitro using ECs from either wild-type or DAF-transgenic pigs. Static leukocyte adhesion and T cell activation assays were performed using porcine ECs as target or effector cells, respectively. The role of the DAF-CD97 interaction was investigated using specific blocking monoclonal antibodies (mAbs) against human DAF and its receptor, CD97, in adhesion assays. RESULTS Adhesion of U937 or Jurkat T cells, both expressing human DAF and CD97, was quantitatively similar for wild-type and transgenic-DAF-expressing pig ECs. Furthermore, blocking the CD97-DAF interaction did not inhibit xenogeneic leukocyte-endothelium adhesion, whereas blocking the very late antigen 4-vascular cell adhesion molecule-1 pathway reduced this adhesion by 50-80%. Furthermore, DAF and CD97 expression was not up-regulated during tumor necrosis factor-alpha- or lipopolysaccharide-mediated EC activation, unlike the adhesion molecules E-selectin, vascular cell adhesion molecule-1, and intracellular adhesion molecule (ICAM)-1. CONCLUSION We found that high levels of human DAF expressed on ECs abrogates C-mediated cell damage but did not affect the in vitro adhesive properties or antigen-presenting cell function of genetically modified porcine ECs.
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Palenciano CG, Segura B, Ramirez P, Chavez R, Munitiz V, Cayuela MG, Acosta F, Sansano T, Majado M, Muñoz A, Hernandez O, Pino-Chavez G, Loba M, Yelamos J, Gago MR, Vizcaino AS, Asensi H, Marin F, Rubio A, Fuente T, Rios A, Montoya M, Robles R, Bueno FS, Rodriguez JM, Navarro F, Cabezuelo J, Cozzi E, White DJG, Parrilla P. Acid-base and electrolyte disturbances in an experimental model of orthotopic liver xenotransplantation from pig to baboon after graft reperfusion: differences between h-DAF livers and unmodified livers. Transplant Proc 2002; 34:325-6. [PMID: 11959309 DOI: 10.1016/s0041-1345(01)02784-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Vangerow B, Hecker JM, Lorenz R, Loss M, Przemeck M, Appiah R, Schmidtko J, Jalali A, Rueckoldt H, Winkler M. C1-Inhibitor for treatment of acute vascular xenograft rejection in cynomolgus recipients of h-DAF transgenic porcine kidneys. Xenotransplantation 2001; 8:266-72. [PMID: 11737852 DOI: 10.1034/j.1399-3089.2001.00130.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
At present, the major barrier to successful discordant xenotransplantation of unmodified or complement regulator transgenic porcine xenografts is acute vascular xenograft rejection (AVR). AVR is associated with the intragraft deposition of induced recipient xenoreactive antibodies and subsequent complement activation. In a life-supporting pig to primate kidney xenotransplantation setting using h-DAF transgenic donor organs and postoperative immunosuppression, episodes of AVR were either treated with boluses of cyclophosphamide and steroids or with the same regimen supplemented by a three-day course of C1-Inhibitor, a multifunctional complement regulator. In 8 out of 10 animals stable initial graft function was achieved; in all animals one or more episodes of AVR were observed. When, in 4 animals, C1-Inhibitor was added to the standard anti-rejection treatment regimen, AVR was successfully reversed in 6 out of 7 episodes, while in another group of 4 animals receiving the standard anti-rejection treatment 0 out of 4 episodes of AVR responded to treatment. Response to anti-rejection treatment was associated with a significant increase in recipient survival time. We conclude that AVR of h-DAF transgenic porcine kidneys can be successfully treated by additional short-term fluid phase complement inhibition.
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Verbakel CA, de Bruin RW, Bonthuis F, Jonker M, Dekker S, Marquet RL, IJzermans JN. Contrast in the efficacy of hDAF mouse hearts between ex vivo perfusion and transplantation into primates. Xenotransplantation 2001; 8:284-91. [PMID: 11737854 DOI: 10.1034/j.1399-3089.2001.00132.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In recent experiments, in which we compared hDAF transgenic rat hearts perfused with 15% human serum in the Langendorff device and hDAF rat hearts transplanted into cynomolgus monkeys, we demonstrated that in the ex vivo heart perfusion model both homozygous and heterozygous hDAF hearts survived longer as nontransgenic controls. Surprisingly, we found that only homozygous hDAF hearts were protected against hyperacute rejection in vivo. The first aim of this study was to determine whether perfusion of mouse hearts with higher human serum concentrations or human blood might explain some of the differences found in survival time of the recently performed experiments with rat heart xenografts. Secondly, we investigated whether the observed differences in survival times of rat xenografts between in vivo and ex vivo transplantation would also hold for mouse hearts transgenic for hDAF. An ex vivo model was used to perfuse hDAF mouse hearts and controls with human serum or blood, and hDAF transgenic hearts and controls were transplanted into cynomolgus monkeys. hDAF transgenic mouse hearts survived significantly longer than their controls when perfused with 15% human serum, but no difference was found when 30% human serum was used, or when these hearts were transplanted into cynomolgus monkeys. However, in both the in vivo and ex vivo models the amount of PMNs adhering to the vascular endothelium was significantly lower in hDAF transgenes as compared with their controls. In conclusion, in the ex vivo situation, the efficacy of hDAF transgenesis in preventing HAR is limited by serum complement concentration.
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Weng WK, Levy R. Expression of complement inhibitors CD46, CD55, and CD59 on tumor cells does not predict clinical outcome after rituximab treatment in follicular non-Hodgkin lymphoma. Blood 2001; 98:1352-7. [PMID: 11520782 DOI: 10.1182/blood.v98.5.1352] [Citation(s) in RCA: 169] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Rituximab is a chimeric monoclonal antibody that targets B-cell-specific antigen CD20 and an effective treatment for B-cell non-Hodgkin lymphoma. Although it is readily used in clinical practice, the exact mechanism of its antitumor effect is unclear. One potential mechanism involves complement-mediated cytotoxicity. It has been shown that rituximab induces complement-mediated cytotoxicity in follicular lymphoma cells in vitro, and complement inhibitors CD55 and CD59 may regulate this process. To determine whether complement inhibitors play a role in regulating the antitumor effect of rituximab, the expression of complement inhibitors CD46, CD55, and CD59 was analyzed in pretreatment tumor cells from 29 rituximab-treated follicular lymphoma patients. Among them, 8 patients achieved complete responses, 11 patients achieved partial responses, and 10 patients showed no or minimal responses to rituximab treatment. Expression of surface CD20, CD46, CD55, and CD59 was determined by 2-color flow cytometry. Although the CD59 level was slightly lower in the complete response group, there was no statistically significant difference in the expression of individual complement inhibitor CD46 (mean channel fluorescence [MCF]: NR, 26.4; PR, 21.9; CR, 29.9), CD55 (MCF: NR, 16.4; PR, 14.9; CR, 23.2), or CD59 (MCF: NR, 41.6; PR, 40.6; CR, 30.6), the combination of any 2 inhibitors, or all 3 on tumor cells from 3 response groups. In addition, there was no difference in the rituximab-induced complement-mediated cytotoxicity in an in vitro assay using tumor cells from 3 response groups. Thus, CD46, CD55, and CD59 expression on pretreatment tumor cells, or their susceptibility to in vitro complement-mediated killing, does not predict clinical outcome after rituximab treatment.
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MESH Headings
- Adult
- Aged
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/therapeutic use
- Antibodies, Monoclonal, Murine-Derived
- Antibody Specificity
- Antibody-Dependent Cell Cytotoxicity
- Antigens, CD/analysis
- Antigens, CD/immunology
- Antigens, Neoplasm/analysis
- Antigens, Neoplasm/immunology
- Antigens, Neoplasm/physiology
- CD55 Antigens/analysis
- CD55 Antigens/immunology
- CD55 Antigens/physiology
- CD59 Antigens/analysis
- CD59 Antigens/immunology
- CD59 Antigens/physiology
- Complement System Proteins/immunology
- Cytotoxicity, Immunologic
- Female
- Flow Cytometry
- Humans
- Immunotherapy
- Lymphoma, Follicular/immunology
- Lymphoma, Follicular/metabolism
- Lymphoma, Follicular/therapy
- Male
- Membrane Cofactor Protein
- Membrane Glycoproteins/analysis
- Membrane Glycoproteins/immunology
- Middle Aged
- Neoplastic Stem Cells/immunology
- Rituximab
- Treatment Outcome
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Abstract
Some echoviruses (EV) that bind decay-accelerating factor (DAF) also bind cells of human and murine origins in a DAF-independent manner. Pretreatment of cells with heparinase 1 or heparin blocks the binding of radiolabeled virus to the cell surface, and heparin prevents infection of rhabdomyosarcoma cells by certain EV, including several low-passage clinical isolates of EV 6 and some EV that do not bind DAF. These studies suggest that heparan sulfate may be of in vivo relevance as an attachment molecule for EV.
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Kirkitadze MD, Barlow PN. Structure and flexibility of the multiple domain proteins that regulate complement activation. Immunol Rev 2001; 180:146-61. [PMID: 11414356 DOI: 10.1034/j.1600-065x.2001.1800113.x] [Citation(s) in RCA: 169] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In this review we summarise more than 10 years of biophysical exploration into the structural biology of the regulators of complement activation (RCA). The five human proteins responsible for regulation of the early events of complement are homologous and are composed largely from building blocks called "complement control protein (CCP) modules". Unlike most multiple domain proteins they do not contain any of the other widely occurring module types. This apparent simplicity of RCA structure, however, is belied by their sophistication of function. In fact, the structures of the individual CCP modules exhibit wide variations on a common theme while the extent and nature of intermodular connections is diverse. Some neighbouring modules within a protein stabilise each other and some co-operate to form specific binding surfaces. The degree of true "modularity" of CCPs is open to debate. The study of RCA proteins clearly illustrates the value of combining complementary structural biology techniques. The results could have implications for folding, evolution, flexibility and structure-function relationships of other molecules in the large, diverse and little understood category of multiple domain proteins.
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Holden N, Cotterill C, Gally D. Examination of regulatory cross-talk between the decay accelerating factor-binding fimbrial/afimbrial adhesins and type I fimbriae. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2001; 485:143-50. [PMID: 11109100 DOI: 10.1007/0-306-46840-9_20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
The revised sequence of DaaA means that the protein is 98% identical to the afimbrial adhesin regulator AFAA-III. While PapB repressed FimB OFF to ON switching in strain AAEC370A, this was not the case for DaaA. PapB, but not DaaA, reduced the level of expression of type 1 fimbriae, in static LB media. Attention is now focused on the amino terminus of the PapB protein as the possible domain involved in cross talk with type 1 fimbriae.
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Frisk G, Jansson K, Ericsson M, Diderholm H. Differences in inhibition of replication between Coxsackie B4 virus strains in various cell lines by antibodies to some cell surface proteins. Virus Res 2001; 73:121-30. [PMID: 11172916 DOI: 10.1016/s0168-1702(00)00217-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Monoclonal antibodies that interact with the decay accelerating factor (DAF, CD55), the lymphocyte homing receptor (CD44) or the intercellular adhesion molecule I (ICAM- 1) were found to inhibit the replication of different strains of Coxsackievirus serotype B4 (CBV-4) to various extent. By adding antibodies to CD55 the replication of two (V345 and VD2921) of seven strains in HeLa cells, three (V89-4557, VD2921 and T318) of seven in A549-10C cells and one (VD2921) of five strains in RD cells was blocked totally. Consequently, the replication of one strain (VD2921) was blocked in all cells indicating that this strain uses CD55 as a receptor or as a co-receptor on all cell lines and is unable to use another cell surface protein. The binding of this strain to the cell surface was inhibited by the antibodies to CD55. None of the CBV-4 strains was blocked totally by adding antibodies to CD44 to HeLa and A549-10C cells, whereas in RD cells the replication of one (T318) of the CBV-4 strains was blocked totally. The antibodies to ICAM-1 did not inhibit totally the replication of any strain in HeLa and RD cells, but it blocked totally the replication of one strain (CBV-4-E) in A549-10C cells. In HeLa and A549-10C cells the degree of replication correlated highly with the degree of cytopathic effect (CPE). In RD cells, four of the strains replicated without CPE. The adding of antibodies to the integrin alpha(v)beta(3) led to slightly enhanced replication of three of the CBV-4 strains in all cell lines. It is concluded that the receptor usage by different strains of CBV-4 varies not only within the same cells but also between different cell lines.
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Heine H, Ulmer AJ, El-Samalouti VT, Lentschat A, Hamann L. Decay-accelerating factor (DAF/CD55) is a functional active element of the LPS receptor complex. JOURNAL OF ENDOTOXIN RESEARCH 2001; 7:227-31. [PMID: 11581575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
Abstract
Previously, we identified an 80 kDa membrane protein (LMP80) that is capable of binding to LPS and lipid A in the presence of LBP and sCD14. LMP80 could also be detected after immuno-coprecipitation of cell membranes with LPS and lipid A, indicating a physical contact of LMP80 and LPS/lipid A. Further analysis and peptide sequencing revealed that LMP80 is identical to CD55 (decay accelerating factor, DAF), a regulatory molecule of the complement cascade. Transfection of LPS-hyporesponsive Chinese hamster ovary (CHO) cells with human CD55 resulted in the translocation of NF-B upon stimulation with LPS or lipid A. Our results demonstrate a new functional role of CD55 as a molecule able to mediate LPS-induced activation of cells that may be part of a multimeric LPS receptor complex.
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Guignot J, Breard J, Bernet-Camard MF, Peiffer I, Nowicki BJ, Servin AL, Blanc-Potard AB. Pyelonephritogenic diffusely adhering Escherichia coli EC7372 harboring Dr-II adhesin carries classical uropathogenic virulence genes and promotes cell lysis and apoptosis in polarized epithelial caco-2/TC7 cells. Infect Immun 2000; 68:7018-27. [PMID: 11083827 PMCID: PMC97812 DOI: 10.1128/iai.68.12.7018-7027.2000] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Diffusely adhering Escherichia coli (DAEC) strains expressing adhesins of the Afa/Dr family bind to epithelial cells in a diffuse adherence pattern by recognizing a common receptor, the decay-accelerating factor (CD55). Recently, a novel CD55-binding adhesin, named Dr-II, was identified from the pyelonephritogenic strain EC7372. In this report, we show that despite the low level of sequence identity between Dr-II and other members of the Afa/Dr family, EC7372 induces pathophysiological effects similar to those induced by other Afa/Dr DAEC strains on the polarized epithelial cell line Caco-2/TC7. Specifically, the Dr-II adhesin was sufficient to promote CD55 and CD66e clustering around adhering bacteria and apical cytoskeleton rearrangements. Unlike other Afa/Dr DAEC strains, EC7372 expresses a functional hemolysin that promotes a rapid cellular lysis. In addition, cell death by apoptosis or necrosis was observed in EC7372-infected Caco-2/TC7 cells, depending on infection time. Our results indicate that EC7372 harbors a pathogenicity island (PAI) similar to the one described for the pyelonephritogenic strain CFT073, which carries both hly and pap operons. Cumulatively, our findings indicate that strain EC7372 can be considered a prototype of a subclass of Afa/Dr DAEC isolates that have acquired a PAI harboring several classical uropathogenic virulence genes.
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Shiraishi M, Nagahama M, Nozato E, Oshiro T, Taira K, Muto Y. Adenovirus-mediated gene transfer of DAF and CD59 in xenogeneic pig liver perfusion. Transplant Proc 2000; 32:2374-5. [PMID: 11120206 DOI: 10.1016/s0041-1345(00)01705-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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69
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Brodbeck WG, Mold C, Atkinson JP, Medof ME. Cooperation between decay-accelerating factor and membrane cofactor protein in protecting cells from autologous complement attack. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 165:3999-4006. [PMID: 11034410 DOI: 10.4049/jimmunol.165.7.3999] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Decay-accelerating factor (DAF or CD55) and membrane cofactor protein (MCP or CD46) function intrinsically in the membranes of self cells to prevent activation of autologous complement on their surfaces. How these two regulatory proteins cooperate on self-cell surfaces to inhibit autologous complement attack is unknown. In this study, a GPI-anchored form of MCP was generated. The ability of this recombinant protein and that of naturally GPI-anchored DAF to incorporate into cell membranes then was exploited to examine the combined functions of DAF and MCP in regulating complement intermediates assembled from purified alternative pathway components on rabbit erythrocytes. Quantitative studies with complement-coated rabbit erythrocyte intermediates constituted with each protein individually or the two proteins together demonstrated that DAF and MCP synergize the actions of each other in preventing C3b deposition on the cell surface. Further analyses showed that MCP's ability to catalyze the factor I-mediated cleavage of cell-bound C3b is inhibited in the presence of factors B and D and is restored when DAF is incorporated into the cells. Thus, the activities of DAF and MCP, when present together, are greater than the sum of the two proteins individually, and DAF is required for MCP to catalyze the cleavage of cell-bound C3b in the presence of excess factors B and D. These data are relevant to xenotransplantation, pharmacological inhibition of complement in inflammatory diseases, and evasion of tumor cells from humoral immune responses.
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70
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Eichler W. CD97 isoform expression in leukocytes. J Leukoc Biol 2000; 68:561-7. [PMID: 11037979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
Different adhesive capacity in interactions with CD55 has been ascribed to the isoforms of the leukocyte CD97 antigen, CD97 (EGF 1,2,5), CD97 (EGF 1,2,3,5), and CD97 (EGF 1,2,3,4,5). In the study, coexpression of the three CD97 isoforms and predominance of CD97 (EGF 1,2,5) transcripts in leukocytes are demonstrated. The contribution of CD97 (EGF 1,2,3,5) and CD97 (EGF 1,2,3,4,5) to total CD97 levels varied among most cell types only slightly, although relatively higher mRNA levels of both isoforms were detected in U 937 cells and monocytes. In peripheral blood lymphocytes, CD97 isoforms did not show clear variation after PMA stimulation and were down-regulated equally after CD97 cross-linking. Moreover, the CD97 isoform pattern was not altered in monocytes after interferon-gamma stimulation and in synovial T cells from patients with rheumatoid arthritis. CD97 mRNA levels did not necessarily correspond to CD97 surface density. The findings suggest that adhesive activity of CD97 toward CD55 is unlikely to be regulated by differential CD97 isoform expression.
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MESH Headings
- Antigens, CD
- Antigens, Neoplasm/biosynthesis
- Antigens, Neoplasm/genetics
- Arthritis, Rheumatoid/pathology
- CD55 Antigens/physiology
- Cell Adhesion
- Cells, Cultured/drug effects
- Cells, Cultured/metabolism
- Gene Expression Regulation/drug effects
- Gene Expression Regulation, Neoplastic/drug effects
- HL-60 Cells/drug effects
- HL-60 Cells/metabolism
- Humans
- Interferon-gamma/pharmacology
- Jurkat Cells/drug effects
- Jurkat Cells/metabolism
- K562 Cells/drug effects
- K562 Cells/metabolism
- Leukocytes/drug effects
- Leukocytes/metabolism
- Membrane Glycoproteins/biosynthesis
- Membrane Glycoproteins/chemistry
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/physiology
- Molecular Weight
- Polymerase Chain Reaction
- Protein Isoforms/biosynthesis
- Protein Isoforms/chemistry
- Protein Isoforms/genetics
- Protein Isoforms/physiology
- Protein Structure, Tertiary
- RNA, Messenger/biosynthesis
- RNA, Messenger/genetics
- RNA, Neoplasm/biosynthesis
- RNA, Neoplasm/genetics
- Receptors, G-Protein-Coupled
- Synovial Fluid/cytology
- T-Lymphocytes/drug effects
- T-Lymphocytes/metabolism
- Tetradecanoylphorbol Acetate/pharmacology
- Transcription, Genetic/drug effects
- U937 Cells/drug effects
- U937 Cells/metabolism
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71
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Accardo-Palumbo A, Triolo G, Colonna-Romano G, Potestio M, Carbone M, Ferrante A, Giardina E, Caimi G, Triolo G. Glucose-induced loss of glycosyl-phosphatidylinositol-anchored membrane regulators of complement activation (CD59, CD55) by in vitro cultured human umbilical vein endothelial cells. Diabetologia 2000; 43:1039-47. [PMID: 10990082 DOI: 10.1007/s001250051487] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
AIMS/HYPOTHESIS This study examines whether increased glucose concentrations are responsible for a decreased expression of membrane regulators of complement activation molecules. The effect of high glucose in determining an increase in membrane attack complex deposition on endothelial cells was also investigated. METHODS Endothelial cells were isolated from umbilical cord tissue, cultured in the presence of increased concentrations of glucose, and the expression of CD46, CD55, and CD59 was detected by ELISA (enzyme-linked immunosorbent assay) and by flow cytometry. Glucose-treated endothelial cells were also incubated with antiendothelial cell antibodies and fresh complement to assess the amount of membrane attack complex formation. RESULTS High concentrations of glucose decreased the expression of CD59 and CD55 by endothelial cells in a time-dependent and glucose concentration-dependent manner without affecting CD46 expression. High concentrations of soluble CD59 were found in the supernatants of cells treated with high glucose. The decrease in CD59 expression induced by high glucose concentrations was reversed by coincubation of cells with a calcium channel blocking agent (Verapamil). All of these effects were not reproduced by osmotic control media. Cells treated with concentrations of high glucose were more susceptible to complement activation and membrane attack complex formation after exposure to antiendothelial cell antibodies. CONCLUSION/INTERPRETATION We speculate that hyperglycaemia could directly contribute to a loss of CD59 and CD55 molecules through a calcium-dependent phosphoinositol-specific phospholipase C activation and subsequent regulation of cell wall expression of GPI-anchored proteins. This phenomenon could facilitate the activation of a complement pathway and could play a part in the aetiology of endothelial dysfunction in diabetes.
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72
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Ramirez P, Chavez R, Majado M, Munitiz V, Muñoz A, Hernandez Q, Palenciano C, Pino-Chavez G, Loba M, Minguela A, Yelamos J, Vizcaino AS, Asensi H, Cayuela MG, Segura B, Marin F, Rubio A, Rios A, Fuente T, Robles R, Sanchez F, Sansano T, Acosta F, Rodriguez JM, Navarro F, Cabezuelo J. The porcine liver supports metabolic homeostasis in the nonhuman primate: experimental study in a model of orthotopic liver transplantation from h-DAF transgenic pig to baboon. Transplant Proc 2000; 32:1112-3. [PMID: 10936385 DOI: 10.1016/s0041-1345(00)01150-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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73
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Abstract
Although complete and partial complement deficiencies are well described in humans and several spontaneous animal models, many questions have remained regarding the exact role that these deficiency states play in the observed clinical manifestations. Likewise, many important mechanistic questions cannot be addressed using patients or spontaneously arising animal models of deficiency states. To provide additional insights and create readily manipulable experimental systems, over the last 5 years mice have been created by several groups in which specifically targeted insertional mutagenesis has resulted in complete deficiencies of complement activation proteins, receptors or regulatory proteins. Many surprising findings have already been made using mice derived from these strategies, and clinically relevant studies have begun to provide great insights into human deficiency states. This review includes an overview of these complement deficient mice and highlights some of the important findings that have resulted from their creation. A discussion of future experimental directions thought to be important by this author then follows and concludes the review.
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74
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Verbakel CA, Bonthuis F, Eerhart SE, van Dixhoorn M, Grosveld F, Marquet RL, IJzermans JN. Relative roles of hCD46 and hCD55 in the regulation of hyperacute rejection. Transplant Proc 2000; 32:903-4. [PMID: 10936266 DOI: 10.1016/s0041-1345(00)01030-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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75
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Bennet W, Sundberg B, Elgue G, Brendel M, Richards A, White DJ, Groth C, Korsgren O. Complement regulatory proteins on human and porcine nontransgenic and hDAF transgenic islet cells: expression and role in susceptibility to lysis by human serum. Transplant Proc 2000; 32:1066. [PMID: 10936358 DOI: 10.1016/s0041-1345(00)01124-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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76
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Loss M, Przemeck M, Schmidtko J, Arends H, Kunz R, Jäger K, Jalali A, Rensing S, Kaup J, Cozzi E, White DJ, Klempnauer J, Winkler M. Long-term survival of cynomolgus monkeys following pig-to-primate kidney xenotransplantation using h-DAF transgenic donor organs. Transplant Proc 2000; 32:1095-6. [PMID: 10936373 DOI: 10.1016/s0041-1345(00)01138-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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77
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van Dixhoorn MG, Dekker S, Janssen RW, Verbakel CA, Grosveld F. Human CD46 rather than CD55 is a key element in protection against complement activation in vitro. Transplant Proc 2000; 32:916-8. [PMID: 10936272 DOI: 10.1016/s0041-1345(00)01036-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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78
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Masroor S, Cozzi E, Soin B, Vial C, Chavez G, Smith KG, Bradley JR, White DJ, Friend PJ. Absence of hyperacute rejection and preservation of function in HDAF transgenic pig kidneys exposed to prolonged cold ischaemia. Transplant Proc 2000; 32:965-6. [PMID: 10936300 DOI: 10.1016/s0041-1345(00)01064-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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79
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Nagahama M, Shiraishi M, Taira K, Ohshiro T, Muto Y. Adenovirus-mediated gene transfer of double human complement regulating proteins (DAF, CD59) in xenogeneic rat kidney perfusion. Transplant Proc 2000; 32:909-10. [PMID: 10936269 DOI: 10.1016/s0041-1345(00)01033-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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80
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Bennet W, Sundberg B, Song Z, Elgue G, Wennberg L, Richards A, White DJ, Larsson R, Nilsson B, Groth C, Korsgren O. Porcine islets of langerhans isolated from normal and hDAF transgenic pigs elicit the same acute inflammatory reaction during exposure to human blood; inhibition of the response with soluble complement receptor 1 and heparin. Transplant Proc 2000; 32:1065. [PMID: 10936357 DOI: 10.1016/s0041-1345(00)01123-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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81
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Shiraishi M, Nagahama M, Nozato E, Oshiro T, Taira K, Muto Y. Adenovirus-mediated gene transfer of the triple human complement regulating proteins (DAF, CD59, MCP) in xenogeneic pig liver perfusion. Transplant Proc 2000; 32:1116-7. [PMID: 10936387 DOI: 10.1016/s0041-1345(00)01152-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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82
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Wiebe K, Steinhoff G, Poeling J, Schröder C, Meliss R, Winkler M, Haverich A. Ex vivo perfusion of swine lungs: lung function in a pig-to-human model of xenotransplantation. Transplant Proc 2000; 32:1149-50. [PMID: 10936396 DOI: 10.1016/s0041-1345(00)01161-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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83
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Hourcade D, Liszewski MK, Krych-Goldberg M, Atkinson JP. Functional domains, structural variations and pathogen interactions of MCP, DAF and CR1. IMMUNOPHARMACOLOGY 2000; 49:103-16. [PMID: 10904110 DOI: 10.1016/s0162-3109(00)80296-9] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The Regulators of Complement Activation (RCA) are a fascinating group of proteins that play important roles in innate and acquired immunity. In this review, we examine structure-function aspects of three membrane-bound RCA proteins and discuss the unique impact of their genetic organization on their evolution.
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84
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Cozzi E, Bhatti F, Schmoeckel M, Chavez G, Smith KG, Zaidi A, Bradley JR, Thiru S, Goddard M, Vial C, Ostlie D, Wallwork J, White DJ, Friend PJ. Long-term survival of nonhuman primates receiving life-supporting transgenic porcine kidney xenografts. Transplantation 2000; 70:15-21. [PMID: 10919569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
BACKGROUND Recently, there has been a resumed interest in clinical xenotransplantation using pig organs. However, no data are available yet regarding the capacity of porcine organs to sustain the life of a primate beyond the first month. We have attempted to obtain long-term survival of nonhuman primates using human decay-accelerating factor (hDAF) transgenic pig organs and an immunosuppressive strategy particularly aimed at neutralizing the humoral component of the immune response. METHODS hDAF transgenic or control kidneys were transplanted into 14 bilaterally nephrectomized cynomolgus monkeys (Macaca fascicularis) that underwent splenectomy and were immunosuppressed with cyclosporine A, cyclophosphamide, and steroids. All animals also received recombinant erythropoietin. Postoperatively, the primates were monitored daily. Laboratory evaluations included serum biochemistry, hematology, and measurements of hemolytic antipig antibodies. To assess the role of splenectomy in the control of humoral response, historical data were also used from a group of monkeys (n=7) that received the same immunosuppressive regimen and an hDAF transgenic porcine kidney but did not have splenectomy or receive recombinant erythropoietin. RESULTS This immunosuppressive approach obtained the longest survival time (78 days) described to date of a primate receiving a life-supporting porcine renal xenograft. Furthermore, four of nine animals in this series survived for 50 days or more. Most biochemical measurements in this study (including plasma urea, creatinine, sodium, and potassium concentrations) remained within normal ranges for several weeks in all of the longest-surviving animals. CONCLUSIONS Normalization of renal function (urea and creatinine) in primate recipients of porcine renal xenografts suggests that pig kidneys may be suitable for future clinical xenotransplantation. Additional immunosuppressive approaches, specifically designed to prevent humorally mediated immunological damage, should be explored to further prolong survival of primates that have received porcine xenografts.
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85
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Shafren DR, Dorahy DJ, Thorne RF, Barry RD. Cytoplasmic interactions between decay-accelerating factor and intercellular adhesion molecule-1 are not required for coxsackievirus A21 cell infection. J Gen Virol 2000; 81:889-94. [PMID: 10725413 DOI: 10.1099/0022-1317-81-4-889] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Coxsackievirus A21 (CAV-21) employs a cell receptor complex of decay-accelerating factor (DAF) and intercellular adhesion molecule-1 (ICAM-1) for cell infectivity. In this study, the nature of potential extra- and/or intracellular interactions between DAF and ICAM-1 involved in picornaviral cell entry was investigated. Firstly, it was shown that intracellular interplay between DAF and ICAM-1 is not required for CAV-21 infection, as CAV-21 lytic infection mediated via the DAF/ICAM-1 receptor complex is not inhibited by replacement of the transmembrane and cytoplasmic domains of ICAM-1 with those from an unrelated cell surface molecule, CD36. By immunoprecipitation, chemical cross-linking and picornaviral binding assays, the existence of a close spatial association between DAF and ICAM-1 on the surface of ICAM-1-transfected RD cells was confirmed. Furthermore, it was shown that potential extracellular DAF/ICAM-1 interactions are likely to occur in an area on or proximal to DAF SCR3 and may influence the route of CAV-21 cell entry.
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86
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Selvarangan R, Goluszko P, Popov V, Singhal J, Pham T, Lublin DM, Nowicki S, Nowicki B. Role of decay-accelerating factor domains and anchorage in internalization of Dr-fimbriated Escherichia coli. Infect Immun 2000; 68:1391-9. [PMID: 10678952 PMCID: PMC97293 DOI: 10.1128/iai.68.3.1391-1399.2000] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Dr-fimbriated Escherichia coli capable of invading epithelial cells recognizes human decay-accelerating factor (DAF) as its cellular receptor. The role of extracellular domains and the glycosylphosphatidylinositol anchor of DAF in the process of internalization of Dr(+) E. coli was characterized in a cell-cell interaction model. Binding of Dr(+) E. coli to the short consensus repeat 3 domain of DAF expressed by Chinese hamster ovary cells was critical for internalization to occur. Deletion of short consensus repeat 3 domain or replacement of Ser(165) by Leu in this domain, or the use of a monoclonal antibody to this region abolished internalization. Replacing the glycosylphosphatidylinositol anchor of DAF with the transmembrane anchor of membrane cofactor protein or HLA-B44 resulted in abolition or reduction of internalization respectively. Cells expressing glycosylphosphatidylinositol-anchored DAF but not the transmembrane-anchored DAF internalized Dr(+) E. coli through a glycolipid pathway, since the former cells were more sensitive to inhibition by methyl-beta-cyclodextrin, a sterol-chelating agent. Electron microscopic studies revealed that the intracellular vacuoles containing the internalized Dr(+) E. coli were morphologically distinct between the anchor variants of DAF. The cells expressing glycosylphosphatidylinositol-anchored DAF contained a single bacterium in tight-fitting vacuoles, while the cells expressing transmembrane-anchored DAF contained multiple (two or three) bacteria in spacious phagosomes. This finding suggests that distinct postendocytic events operate in the cells expressing anchor variants of DAF. We provide direct evidence for the DAF-mediated internalization of Dr(+) E. coli and demonstrate the significance of the glycosylphosphatidylinositol anchor, which determines the ability and efficiency of the internalization event.
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87
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Gorter A, Meri S. Immune evasion of tumor cells using membrane-bound complement regulatory proteins. IMMUNOLOGY TODAY 1999; 20:576-82. [PMID: 10562709 DOI: 10.1016/s0167-5699(99)01537-6] [Citation(s) in RCA: 166] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Membrane-bound complement regulatory proteins (mCRPs) play an important role in the protection of cells from complement-mediated injury. It is now apparent that malignant tumor cells also express these proteins to escape complement attack. Here, Arko Gorter and Seppo Meri discuss the implications of complement resistance for the immunotherapeutic treatment of solid tumors with monoclonal antibodies.
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88
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Hensel F, Hermann R, Schubert C, Abé N, Schmidt K, Franke A, Shevchenko A, Mann M, Müller-Hermelink HK, Vollmers HP. Characterization of glycosylphosphatidylinositol-linked molecule CD55/decay-accelerating factor as the receptor for antibody SC-1-induced apoptosis. Cancer Res 1999; 59:5299-306. [PMID: 10537313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
The human monoclonal antibody SC-1 induces apoptosis of stomach carcinoma cells and is currently used in a clinical Phase II trial. The antibody binds to a target molecule that is preferentially expressed on diffuse- and intestinal-type stomach cancer cells and shows a very restricted expression on other normal and malignant tissues. In this paper, we show that the SC-1 receptor is a stomach carcinoma-associated isoform of CD55 [membrane-bound decay-accelerating factor (DAF)-B] with a relative molecular mass of approximately 82 kDa. The antigenic site of SC-1 is an N-linked carbohydrate residue. Cross-linking of the DAF receptor increases apoptotic activity. SC-1 binding induces tyrosine phosphorylation of three proteins of approximately 60, 75, and 110 kDa, whereas a serine residue of an approximately 35-kDa protein is dephosphorylated. Expression of caspase-3 (CPP32) and caspase-8 (FLICE) is elevated, and activation of these caspases occurs. These data show that a tumor-specific variant form DAF is involved in apoptosis and can be used for adjuvant therapeutical purposes on gastric carcinoma.
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89
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Mason JC, Yarwood H, Sugars K, Morgan BP, Davies KA, Haskard DO. Induction of decay-accelerating factor by cytokines or the membrane-attack complex protects vascular endothelial cells against complement deposition. Blood 1999; 94:1673-82. [PMID: 10477692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023] Open
Abstract
Vascular endothelium is continuously exposed to complement-mediated challenge, and this is enhanced during inflammation. Although the complement-regulatory proteins decay-accelerating factor (DAF), CD59, and membrane cofactor protein (MCP) protect endothelial cells (ECs) against complement-mediated injury, the control of their expression and relative contributions to vascular protection is unclear. We explored the hypothesis that mechanisms exist which induce upregulation of complement-regulatory proteins on ECs to maintain vascular function in inflammation. Tumor necrosis factor alpha (TNFalpha) and interferon gamma (IFNgamma) each increased DAF expression but not CD59 or MCP expression, and a combination of these cytokines was more potent than either alone. Cytokine-induced expression depended on increased DAF mRNA and de novo protein synthesis and was maximal by 72 hours. In addition, assembly of the membrane-attack complex (MAC) on ECs induced a 3-fold increase in DAF expression, and this was enhanced by cytokines. DAF upregulation was not inhibited by protein kinase C (PKC) antagonists. The increase in DAF was functionally relevant since it reduced complement 3 (C3) deposition by 40%, and this was inhibited by an anti-DAF monoclonal antibody. These observations indicate that upregulation of DAF expression by cytokines or MAC may represent an important feedback mechanism to maintain the integrity of the microvasculature during subacute and chronic inflammatory processes involving complement activation.
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90
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Hiasa A, Watanabe M, Okada H, Ikenaka K, Fujita T, Yoshimatsu T, Kanematsu T, Shiku H. Retroviruses prepared from human DAF expressing murine packaging cells acquire resistance against human serum. Int J Oncol 1999; 14:1091-6. [PMID: 10339663 DOI: 10.3892/ijo.14.6.1091] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The complement system of the human body inactivates the infectious ability of retroviruses injected as an artificial gene transfer vector. We established new murine leukemia virus (MuLV) packaging cell lines; D2SS and D7S which express decay-accelerating factor (DAF) on their surface. Both D2SS and D7S were resistant against incubation with fresh human serum. Moreover, the retroviruses produced from these packaging cell lines were also resistant to serum treatment. This resistance can be inhibited by DAF neutralizing antibody 1C6. These data demostrate that DAF induces a partial protection of MuLV infection from the human complement system.
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91
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Hochgrebe TT, Humphreys D, Wilson MR, Easterbrook-Smith SB. A reexamination of the role of clusterin as a complement regulator. Exp Cell Res 1999; 249:13-21. [PMID: 10328949 DOI: 10.1006/excr.1999.4459] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Clusterin is a highly conserved glycoprotein which has been proposed to protect host cells against complement-mediated cytolysis. We tested the hypothesis that clusterin is a complement regulator using erythrocytes and cells which had been stably transfected with a membrane-anchored form of clusterin as targets for complement-mediated cytolysis. Clusterin gave dose-dependent protection of antibody-coated sheep erythrocytes against complement-mediated lysis by diluted normal human serum. There was a linear relationship between the concentration of clusterin giving 50% protection and the concentration of serum; extrapolation of this to the case of undiluted human serum showed that a clusterin concentration at least two orders of magnitude greater than its physiological plasma concentration would be needed to confer protection against complement-mediated cytolysis under physiological conditions. Physiological concentrations of clusterin did not protect rabbit erythrocytes against alternative complement pathway-mediated lysis using dilute human serum. Exogenous clusterin had no effect on lysis of human erythrocytes triggered by the addition of inulin to autologous human serum. Induction of cell-surface clusterin expression by L929 (murine fibroblast) cells which had been stably transfected with cDNA for human clusterin linked to DNA coding for the 44 C-terminal amino acid residues of CD55 did not protect the cells against complement-mediated lysis by either normal or clusterin-depleted human serum. These data suggest that clusterin may not be a physiologically relevant regulator of complement activation.
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92
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Yeatman M, Daggett CW, Lau CL, Byrne GW, Logan JS, Platt JL, Davis RD. Human complement regulatory proteins protect swine lungs from xenogeneic injury. Ann Thorac Surg 1999; 67:769-75. [PMID: 10215226 DOI: 10.1016/s0003-4975(99)00049-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
BACKGROUND Pulmonary xenotransplantation is not possible because of hyperacute lung injury, the pathogenesis of which is unknown. This study evaluates complement-dependent pathways of pulmonary injury during heterologous perfusion of swine lungs. METHODS Lungs from unmodified swine and swine expressing human decay-accelerating factor and human CD59 (hDAF/hCD59 swine) were perfused with either human plasma or baboon blood. Pulmonary vascular resistance and static pulmonary compliance were measured serially, and swine lung tissue were examined by light microscopy. Complement activation was assessed by serial measurements of baboon plasma C3a-desArg concentrations. RESULTS Perfusion of unmodified swine lungs with human plasma and baboon blood resulted in hyperacute lung injury within minutes of perfusion. However, function was preserved in swine lungs expressing human decay-accelerating factor and human CD59. In both study groups, xenogeneic perfusion with baboon blood resulted in at least a sevenfold increase in plasma C3a-desArg levels suggesting transient activation of complement. CONCLUSIONS Lungs from swine expressing human decay-accelerating factor and human CD59 were resistant to injury during perfusion with human plasma and baboon blood, indicating that complement mediated some of the features of xenogeneic acute lung injury.
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Lavitrano M, Stoppacciaro A, Bacci ML, Forni M, Fioretti D, Pucci L, Di Stefano C, Lazzereschi D, Rughetti A, Ceretta S, Zannoni A, Rahimi H, Moioli B, Rossi M, Nuti M, Rossi G, Seren E, Alfani D, Cortesini R, Frati L. Human decay accelerating factor transgenic pigs for xenotransplantation obtained by sperm-mediated gene transfer. Transplant Proc 1999; 31:972-4. [PMID: 10083433 DOI: 10.1016/s0041-1345(98)01863-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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94
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Bhatti FN, Schmoeckel M, Zaidi A, Cozzi E, Chavez G, Goddard M, Dunning JJ, Wallwork J, White DJ. Three-month survival of HDAFF transgenic pig hearts transplanted into primates. Transplant Proc 1999; 31:958. [PMID: 10083425 DOI: 10.1016/s0041-1345(98)01855-7] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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95
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Schmoeckel M, Bhatti FN, Zaidi A, Cozzi E, Chavez G, Wallwork J, White DJ, Friend PJ. Splenectomy improves survival of HDAF transgenic pig kidneys in primates. Transplant Proc 1999; 31:961. [PMID: 10083427 DOI: 10.1016/s0041-1345(98)01857-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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96
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Abstract
Decay-accelerating factor (DAF) mediates cellular attachment for many human picornaviruses. In most cases, viral binding to DAF is itself insufficient to permit cell infectivity, with a second, functional internalization receptor being required to facilitate this process. Previously, we postulated that the role of DAF in enterovirus cell infection is as a sequestration receptor, maintaining a reservoir of bound virus in an infectious state, awaiting interaction with functional internalization receptors. Many of these functional receptors possess the capacity to induce relatively rapid changes in capsid conformations, resulting in the formation of altered particles (A-type particles). In this report, we show that antibody-cross-linked DAF, in contrast to endogenous surface-expressed forms, can act as a functional virus receptor to mediate coxsackie A21 virus (CAV21) lytic cell infection. In contrast to the situation with ICAM-1-mediated CAV21 infection, in which high levels of A-type particles are formed, cross-linked DAF-induced CAV21 replication occurs in the absence of detectable A-particle formation.
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97
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Abstract
Complement activation plays a critical role in the pathogenesis of many forms of glomerulonephritis. Complement activation leads to tissue injury through various mechanisms including the generation of chemotactic factors and activation of the resident glomerular cells following C5b-9 insertion. Recent advances have disclosed the mechanisms of regulation of complement activation by discovery of a number of complement regulatory proteins. Decay accelerating factor (DAF), membrane cofactor protein (MCP), and complement receptor type 1 (CR1) act by inactivating C3/C5 convertase. They belong to the gene superfamily known as the regulators of complement activation (RCA), and share a common structural motif called a short consensus repeat (SCR). In contrast, CD59 works by inhibiting formation of C5b-9. The glomerulus is particularly well endowed with these membrane-bound complement regulatory proteins. DAF, MCP, and CD59 are ubiquitously expressed by all three resident glomerular cells, while CR1 is localized exclusively in podocytes. Expression of complement regulatory proteins can be changed by many factors including complement attack itself, and their expression levels are affected in various glomerular disorders. Studies utilizing cultured glomerular cells and animal models of glomerular diseases suggest important protective roles of complement regulatory proteins against immune-mediated renal injury. Recent progress in molecular biological techniques has made new therapeutic strategy feasible. Systemic administration of soluble recombinant complement regulatory proteins and local overexpression of complement regulatory proteins are promising therapeutic approaches.
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98
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Kalady MF, Lawson JH, Sorrell RD, Platt JL. Decreased fibrinolytic activity in porcine-to-primate cardiac xenotransplantation. Mol Med 1998; 4:629-37. [PMID: 9848079 PMCID: PMC2230314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
BACKGROUND One major barrier to successful xenotransplantation is acute vascular rejection, a process pathologically characterized by microvascular thrombosis and diffuse fibrin deposition in transplant blood vessels. This pathologic picture may result from a disturbance in the coagulant or fibrinolytic pathways that regulate normal vascular patency. This study evaluated the regulation of fibrinolytic activity defined by tissue plasminogen activator and plasminogen activator inhibitor-1 as it may exist in the setting of acute vascular rejection. MATERIALS AND METHODS, RESULTS Serial biopsies from cardiac xenotransplants evaluated by immunofluorescence microscopy demonstrated progressive decreases in tissue plasminogen activator and increases in plasminogen activator inhibitor-1. In vitro studies measuring fibrinolytic activity of cell culture medium from porcine aortic endothelial cells stimulated with human serum or autologous porcine serum revealed that human serum triggered as much as 93% increase in antifibrinolytic activity. CONCLUSIONS These findings demonstrate that porcine vascular endothelial cells change toward an antifibrinolytic state following stimulation with human xenoreactive antibodies and complement. The shift is at least partly explained by an increased ratio of plasminogen activator inhibitor-1 to tissue plasminogen activator, and is at least in part mediated by the activation of complement. This increased antifibrinolytic activity may contribute to the thrombotic diathesis seen in acute vascular rejection in pig-to-primate xenografts.
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99
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Bhatti FN, Zaidi A, Schmoeckel M, Cozzi E, Chavez G, Wallwork J, White DJ, Friend PJ. Survival of life-supporting HDAF transgenic kidneys in primates is enhanced by splenectomy. Transplant Proc 1998; 30:2467. [PMID: 9723540 DOI: 10.1016/s0041-1345(98)00689-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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100
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Zaidi A, Bhatti F, Schmoeckel M, Cozzi E, Chavez G, Wallwork J, White D, Friend P. Kidneys from HDAF transgenic pigs are physiologically compatible with primates. Transplant Proc 1998; 30:2465-6. [PMID: 9723539 DOI: 10.1016/s0041-1345(98)00688-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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