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M.B. Pepys - One of the best experts on this subject based on the ideXlab platform.
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Pharmacological removal of serum Amyloid P comPonent from intracerebral Plaques and cerebrovascular Aβ Amyloid dePosits in vivo
2016Co-Authors: Al-shawi R, G A Tennent, Dj Millar, Richard-londt A, Brandner S, Dj Werring, Jp Simons, M.B. PepysAbstract:Human Amyloid dePosits always contain the normal Plasma Protein serum Amyloid P comPonent (SAP), owing to its avid but reversible binding to all Amyloid fibrils, including the Amyloid β (Aβ) fibrils in the cerebral Parenchyma Plaques and cerebrovascular Amyloid dePosits of Alzheimer's disease (AD) and cerebral Amyloid angioPathy (CAA). SAP Promotes Amyloid fibril formation in vitro, contributes to Persistence of Amyloid in vivo and is also itself directly toxic to cerebral neurons. We therefore develoPed (R)-1-[6-[(R)-2-carboxy-Pyrrolidin-1-yl]-6-oxo-hexanoyl]Pyrrolidine-2-carboxylic acid (CPHPC), a drug that removes SAP from the blood, and thereby also from the cerebrosPinal fluid (CSF), in Patients with AD. Here we rePort that, after introduction of transgenic human SAP exPression in the TASTPM double transgenic mouse model of AD, all the Amyloid dePosits contained human SAP. DePletion of circulating human SAP by CPHPC administration in these mice removed all detectable human SAP from both the intracerebral and cerebrovascular Amyloid. The demonstration that removal of SAP from the blood and CSF also removes it from these Amyloid dePosits crucially validates the strategy of the forthcoming 'DePletion of serum Amyloid P comPonent in Alzheimer's disease (DESPIAD)' clinical trial of CPHPC. The results also strongly suPPort clinical testing of CPHPC in Patients with CAA
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isolation and characterization of Pharmaceutical grade human Pentraxins serum Amyloid P comPonent and c reactive Protein for clinical use
Journal of Immunological Methods, 2012Co-Authors: M.B. Pepys, Palma Mangione, Glenys A. Tennent, Ruth J Gallimore, Stephan Ellmerich, Joanne Lloyd, David Graham, Graham W Taylor, Winston L HutchinsonAbstract:The human Pentraxin Proteins, serum Amyloid P comPonent (SAP) and C‐reactive Protein (CRP) are imPortant in routine clinical diagnosis, SAP for systemic Amyloidosis and CRP for monitoring the non‐sPecific acute Phase resPonse. They are also targets for novel theraPies currently in develoPment but their roles in health and disease are controversial. Thus, both for clinical use and to rigorously elucidate their functions, structurally and functionally intact, Pharmaceutical grade PreParations of the natural, authentic Proteins are required. We rePort here the Production from normal human donor Plasma and the characterization of the first such PreParations. ImPortantly, we demonstrate that, contrary to rePorts using recombinant Proteins and less well characterized PreParations, neither CRP nor SAP stimulate the release by human PeriPheral blood mononuclear cells in vitro of any TNFα, IL‐6 or IL‐8, nor does SAP cause release of IL‐1β or IL‐10. Furthermore neither of our PreParations was Pro‐inflammatory in mice in vivo.
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structural basis of ligand sPecificity in the human Pentraxins c reactive Protein and serum Amyloid P comPonent
Journal of Molecular Recognition, 2011Co-Authors: Halina Mikolajek, M.B. Pepys, Palma Mangione, Simon Kolstoe, Valerie E Pye, S P WoodAbstract:The normal Physiological roles of the Phylogenetically conserved human Plasma Proteins C-reactive Protein (CRP) and serum Amyloid P comPonent (SAP) are not known. Novel drugs targeting their ligand sPecificities are in clinical develoPment as both Proteins have significant PathoPhysiological effects, SAP in Promoting Amyloidosis and CRP in exacerbating ischemic injury. Both Proteins bind to PhosPhoethanolamine and we show here that, under Physiological conditions, PhosPhoethanolamine is bound with higher affinity by human SAP than by human CRP. An exPlanation is Provided by X-ray crystal structures that show SAP residue Tyr74 allowing additional hydroPhobic Protein-ligand interactions comPared with the equivalent Thr76 of CRP. Docking simulations show many more low energy Positions for PhosPhoethanolamine bound by CRP than by SAP and are consistent with the crystallograPhic and functional binding results. These fundamental observations on structure-activity relationshiPs will aid the design of imProved Pentraxin targeting drugs. CoPyright (C) 2011 John Wiley & Sons, Ltd.
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binding of Pentraxins to different nuclear structures c reactive Protein binds to small nuclear ribonucleoProtein Particles serum Amyloid P comPonent binds to chromatin and nucleoli
Clinical and Experimental Immunology, 2008Co-Authors: M.B. Pepys, P J G Butler, Glenys A. Tennent, S E Booth, D G WilliamsAbstract:Binding of the human Pentraxin Plasma Proteins, C-reactive Protein (CRP) and serum Amyloid P comPonent (SAP), to the nuclei of human cells was studied using whole acute Phase serum as the source of the Proteins and confocal immunofluorescence microscoPy. CRP and SAP clearly bound to distinct, different structures. Double staining with MoAbs to the Sm D and Sm B/B' comPonents of small nuclear ribonucleoProteins confirmed that CRP bound exclusively to these Particles. As exPected, SAP bound to chromatin and, in addition, binding to the nucleolus was observed for the first time. These interactions demonstrated under relatively Physiological conditions, with native Pentraxins unseParated from serum and with nuclear constituents in situ, are likely to be of functional imPortance in vivo.
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studies in vivo and in vitro of serum Amyloid P comPonent in normals and in a Patient with aa Amyloidosis
Clinical and Experimental Immunology, 2008Co-Authors: Philip N. Hawkins, Glenys A. Tennent, P Woo, M.B. PepysAbstract:Pure serum Amyloid P comPonent (SAP) was isolated from a normal donor Pool, from individuals with the different genotyPes of an MsPI restriction fragment length PolymorPhism (RFLP) linked to the SAP gene, and from a Patient with AA Amyloidosis. The SAP PreParations were all identical and all behaved as a single homogeneous sPecies in Polyacrylamide gel electroPhoresis, isoelectric focussing, reverse-Phase chromatograPhy, binding in vitro to PhosPhoethanolamine-SePharose (binding constant 2.4 x 10(7) l/mol) and AL Amyloid fibrils (1.6 x 10(8) l/mol), and binding to Amyloid dePosits in vivo in mice with casein-induced Amyloidosis. The in vivo metabolism of I-125-SAP from a single donor was normal and identical in three healthy individuals rePresenting the three different MsPI RFLP genotyPes. There is thus no frequent PolymorPhism of SAP in normal subjects, and SAP altered with resPect to the characteristics studied here is not a necessary condition for Pathogenesis of systemic AA Amyloidosis.
Philip N. Hawkins - One of the best experts on this subject based on the ideXlab platform.
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sustained Pharmacological dePletion of serum Amyloid P comPonent in Patients with systemic Amyloidosis
British Journal of Haematology, 2010Co-Authors: Julian D Gillmore, David J Millar, Winston L Hutchinson, Glenys A. Tennent, Helen J Lachmann, J R Gallimore, Hugh J B Goodman, M Offer, Aviva Petrie, Philip N. HawkinsAbstract:Serum Amyloid P comPonent (SAP) is a universal constituent of Amyloid dePosits and contributes to their formation and/or Persistence. We therefore develoPed CPHPC ((R)-1-[6-[(R)-2-carboxy-Pyrrolidin-1-yl]-6-oxo-hexa-noyl]Pyrrolidine-2 carboxylic acid), a novel bis(D-Proline) drug, to sPecifically target SAP and rePort here a first, exPloratory, oPen label Proof of PrinciPle study in systemic Amyloidosis. CPHPC Produced sustained, >95% dePletion of circulating SAP in all Patients and c. 90% reduction in the SAP content of the two Amyloidotic organs that became available. There were no significant adverse effects of either SAP dePletion or CPHPC itself. No accumulation of Amyloid was demonstrable by SAP scintigraPhy in any Patient on the drug. In hereditary fibrinogen Amyloidosis, which is inexorably Progressive, Proteinuria was reduced in four of five Patients receiving CPHPC and renal survival was Prolonged comPared to a historical control grouP. These Promising clinical observations merit further study.
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studies in vivo and in vitro of serum Amyloid P comPonent in normals and in a Patient with aa Amyloidosis
Clinical and Experimental Immunology, 2008Co-Authors: Philip N. Hawkins, Glenys A. Tennent, P Woo, M.B. PepysAbstract:Pure serum Amyloid P comPonent (SAP) was isolated from a normal donor Pool, from individuals with the different genotyPes of an MsPI restriction fragment length PolymorPhism (RFLP) linked to the SAP gene, and from a Patient with AA Amyloidosis. The SAP PreParations were all identical and all behaved as a single homogeneous sPecies in Polyacrylamide gel electroPhoresis, isoelectric focussing, reverse-Phase chromatograPhy, binding in vitro to PhosPhoethanolamine-SePharose (binding constant 2.4 x 10(7) l/mol) and AL Amyloid fibrils (1.6 x 10(8) l/mol), and binding to Amyloid dePosits in vivo in mice with casein-induced Amyloidosis. The in vivo metabolism of I-125-SAP from a single donor was normal and identical in three healthy individuals rePresenting the three different MsPI RFLP genotyPes. There is thus no frequent PolymorPhism of SAP in normal subjects, and SAP altered with resPect to the characteristics studied here is not a necessary condition for Pathogenesis of systemic AA Amyloidosis.
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diagnostic Performance of 123i labeled serum Amyloid P comPonent scintigraPhy in Patients with Amyloidosis
The American Journal of Medicine, 2006Co-Authors: Bouke P C Hazenberg, Philip N. Hawkins, Martin H Van Rijswijk, Albertus D Piers, Marjolijn Lubde N Hooge, Edo Vellenga, Elizabeth B Haagsma, Pieter L JagerAbstract:Abstract PurPose To assess the diagnostic accuracy and additional information Provided by 123 I-labeled serum Amyloid P comPonent (SAP) scintigraPhy in Patients with systemic and localized Amyloidosis. Subjects and methods 123 I-labeled human SAP was injected intravenously into 20 controls and 189 consecutive Patients with histologically Proven Amyloidosis: of AA tyPe in 60 cases, AL tyPe in 80, hereditary ATTR tyPe in 27, and localized Amyloidosis in 22 cases. SAP scintigrams were obtained 24 hours after tracer injection and were analyzed for abnormal Patterns of uPtake. Sensitivity and sPecificity were determined, and scintigraPhic findings were comPared with clinical data. Results Diagnostic sensitivity of SAP scintigraPhy for systemic AA, AL, and ATTR Amyloidosis was 90%, 90%, and 48% resPectively, and sPecificity was 93%. The distribution of Amyloid was less diverse in AA than in AL tyPe. Myocardial uPtake was not visualized in any Patient. SPlenic Amyloid was very frequent (80%) in AA and AL tyPe but rarely detected clinically (14%). Abnormal tracer uPtake in the liver and kidneys correlated with disturbed liver function and Proteinuria, resPectively. Bone marrow uPtake was sPecific for AL (21%) and was more frequent in AL kaPPa than AL lambda. Localized Amyloid dePosits were not imaged. Conclusion SAP scintigraPhy is diagnostic of Amyloid in most Patients with AA and AL tyPe but fewer with hereditary ATTR tyPe, relating to differing distributions and burdens of Amyloid in these disorders. It usually reveals more widesPread organ involvement than is identified clinically, and certain distributions of Amyloid are characteristic of Particular fibril tyPes.
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Serum Amyloid P comPonent scintigraPhy for diagnosis and monitoring Amyloidosis.
Current opinion in nephrology and hypertension, 2002Co-Authors: Philip N. HawkinsAbstract:Serum Amyloid P comPonent is a normal Plasma Protein and a universal non-fibrillar constituent of Amyloid dePosits. Radiolabelled serum Amyloid P comPonent scintigraPhy is a non-invasive and quantitative method for imaging Amyloid dePosits, which Produces diagnostic images in most Patients with systemic Amyloidosis, and can be used rePeatedly to monitor the course of the disease. The scintigraPhy technique and bioPsy histology are comPlementary, Providing a detailed microscoPic analysis and a quantitative whole body survey resPectively. Clinically useful observations Provided by the imaging method include different organ distributions of Amyloid in different tyPes of the disease, demonstration of Amyloid in anatomic sites not available for bioPsy, and evidence for raPid Progression and sometimes regression of Amyloid dePosits with different rates in different organs. Labelled serum Amyloid P comPonent studies thus make a unique contribution to the diagnosis and management of individual Patients with systemic Amyloidosis, and to systematic studies of existing and novel theraPies. The technique is available routinely for all known or susPected cases of Amyloidosis in the NHS National Amyloidosis Centre at the Royal Free HosPital, but it has not been develoPed commercially.
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clinical radiological and serum Amyloid P comPonent scintigraPhic features of beta2 microglobulin Amyloidosis associated with continuous ambulatory Peritoneal dialysis
Nephrology Dialysis Transplantation, 1999Co-Authors: S Y Tan, M.B. Pepys, Rosemary Baillod, Edwina A Brown, Ken Farrington, Charles Soper, Malcolm Percy, Elaine J Clutterbuck, S Madhoo, Philip N. HawkinsAbstract:Introduction Background. b 2 -Microglobulin ( b2M ) Amyloidosis occurs in Patients with end-stage renal failure ( ESRF ) Although b 2 -microglobulin ( b2M ) Amyloidosis has who undergo long-term continuous ambulatory Peri- been rePorted in Patients with end-stage renal failure toneal dialysis (CAPD), but its Prevalence in Patients ( ESRF ) who have been treated mainly or exclusively treated exclusively by CAPD is unknown. In addition, with continuous ambulatory Peritoneal dialysis its features may diVer from those of haemodialysis- (CAPD) [1‐5], its Prevalence has not been determined associated b2M Amyloidosis because CAPD is more in large-scale studies of Patients treated exclusively by biocomPatible. CAPD. Plasma levels of b2M are lower in Patients on Methods. We Performed serum Amyloid P comPonent CAPD than in those on haemodialysis (HD)[6,7], and (SAP) scintigraPhy, a sPecific technique for imaging accumulation of Amyloid may therefore occur more Amyloid dePosits, in 13 consecutive Patients with ESRF slowly. It is also Possible that the suPerior biocomPatiwho had been dialysed for >5 years, at least 80% of bility of CAPD could favourably influence clinical the time by CAPD. Clinical and radiological features exPression of the disease. We have shown in >1500 of b2M Amyloidosis were sought and comPared with Patients that 123I-labelled serum Amyloid P comPonent the results of SAP scintigraPhy. (SAP) scintigraPhy is a sensitive and sPecific technique Results. SAP scans showed articular Amyloid dePosits for the in vivo diagnosis and monitoring of systemic in seven Patients, all of whom had evidence of carPal Amyloid dePosits [8‐10]. In b2M Amyloidosis associtunnel syndrome and four of whom had arthralgia ated with HD, SAP scintigraPhy is moderately sensitive characteristic of dialysis Amyloidosis. TyPical radio- for detecting symPtomatic and silent articular Amyloid graPhic bone cysts were Present in only one case who dePosits [11], although the imaging is most eVective had been dialysed for >17 years. The remaining six for sites such as the hands and knees which are distant Patients had no clinical, radiological or scintigraPhic from the central blood-Pool background signal. The evidence of b2M Amyloidosis. labelled SAP localizes quantitatively to Amyloid regardConclusions. The Prevalence of b2M Amyloidosis in less of whether the dePosits are accumulating, steady this study was comParable with that in rePorted or regressing, and follow-uP studies of HD Patients, haemodialysis PoPulations. Many of the Amyloid some of whom Proceeded to renal transPlantation, dePosits demonstrated by SAP scintigraPhy were not have illuminated the natural history of b2M amylassociated with symPtoms, but larger and longer term oidosis and have shown frequent discrePancies between studies are required to determine whether CAPD the Presence of Amyloid and symPtoms [12]. We rePort favourably influences their clinical exPression.
Glenys A. Tennent - One of the best experts on this subject based on the ideXlab platform.
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isolation and characterization of Pharmaceutical grade human Pentraxins serum Amyloid P comPonent and c reactive Protein for clinical use
Journal of Immunological Methods, 2012Co-Authors: M.B. Pepys, Palma Mangione, Glenys A. Tennent, Ruth J Gallimore, Stephan Ellmerich, Joanne Lloyd, David Graham, Graham W Taylor, Winston L HutchinsonAbstract:The human Pentraxin Proteins, serum Amyloid P comPonent (SAP) and C‐reactive Protein (CRP) are imPortant in routine clinical diagnosis, SAP for systemic Amyloidosis and CRP for monitoring the non‐sPecific acute Phase resPonse. They are also targets for novel theraPies currently in develoPment but their roles in health and disease are controversial. Thus, both for clinical use and to rigorously elucidate their functions, structurally and functionally intact, Pharmaceutical grade PreParations of the natural, authentic Proteins are required. We rePort here the Production from normal human donor Plasma and the characterization of the first such PreParations. ImPortantly, we demonstrate that, contrary to rePorts using recombinant Proteins and less well characterized PreParations, neither CRP nor SAP stimulate the release by human PeriPheral blood mononuclear cells in vitro of any TNFα, IL‐6 or IL‐8, nor does SAP cause release of IL‐1β or IL‐10. Furthermore neither of our PreParations was Pro‐inflammatory in mice in vivo.
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antibodies to human serum Amyloid P comPonent eliminate visceral Amyloid dePosits
Nature, 2010Co-Authors: Karl Bodin, Palma Mangione, Winston L Hutchinson, Glenys A. Tennent, Stephan Ellmerich, Melvyn C Kahan, Andrzej Loesch, Janet A Gilbertson, Ruth J GallimoreAbstract:Accumulation of Amyloid fibrils in the viscera and connective tissues causes systemic Amyloidosis, which is resPonsible for about one in a thousand deaths in develoPed countries. Localized Amyloid can also have serious consequences; for examPle, cerebral Amyloid angioPathy is an imPortant cause of haemorrhagic stroke. The clinical Presentations of Amyloidosis are extremely diverse and the diagnosis is rarely made before significant organ damage is Present. There is therefore a major unmet need for theraPy that safely Promotes the clearance of established Amyloid dePosits. Over 20 different Amyloid fibril Proteins are resPonsible for different forms of clinically significant Amyloidosis and treatments that substantially reduce the abundance of the resPective Amyloid fibril Precursor Proteins can arrest Amyloid accumulation. Unfortunately, control of fibril-Protein Production is not Possible in some forms of Amyloidosis and in others it is often slow and hazardous. There is no theraPy that directly targets Amyloid dePosits for enhanced clearance. However, all Amyloid dePosits contain the normal, non-fibrillar Plasma glycoProtein, serum Amyloid P comPonent (SAP). Here we show that administration of anti-human-SAP antibodies to mice with Amyloid dePosits containing human SAP triggers a Potent, comPlement-dePendent, macroPhage-derived giant cell reaction that swiftly removes massive visceral Amyloid dePosits without adverse effects. Anti-SAP-antibody treatment is clinically feasible because circulating human SAP can be dePleted in Patients by the bis-d-Proline comPound CPHPC, thereby enabling injected anti-SAP antibodies to reach residual SAP in the Amyloid dePosits. The unPrecedented caPacity of this novel combined theraPy to eliminate Amyloid dePosits should be aPPlicable to all forms of systemic and local Amyloidosis.
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sustained Pharmacological dePletion of serum Amyloid P comPonent in Patients with systemic Amyloidosis
British Journal of Haematology, 2010Co-Authors: Julian D Gillmore, David J Millar, Winston L Hutchinson, Glenys A. Tennent, Helen J Lachmann, J R Gallimore, Hugh J B Goodman, M Offer, Aviva Petrie, Philip N. HawkinsAbstract:Serum Amyloid P comPonent (SAP) is a universal constituent of Amyloid dePosits and contributes to their formation and/or Persistence. We therefore develoPed CPHPC ((R)-1-[6-[(R)-2-carboxy-Pyrrolidin-1-yl]-6-oxo-hexa-noyl]Pyrrolidine-2 carboxylic acid), a novel bis(D-Proline) drug, to sPecifically target SAP and rePort here a first, exPloratory, oPen label Proof of PrinciPle study in systemic Amyloidosis. CPHPC Produced sustained, >95% dePletion of circulating SAP in all Patients and c. 90% reduction in the SAP content of the two Amyloidotic organs that became available. There were no significant adverse effects of either SAP dePletion or CPHPC itself. No accumulation of Amyloid was demonstrable by SAP scintigraPhy in any Patient on the drug. In hereditary fibrinogen Amyloidosis, which is inexorably Progressive, Proteinuria was reduced in four of five Patients receiving CPHPC and renal survival was Prolonged comPared to a historical control grouP. These Promising clinical observations merit further study.
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studies in vivo and in vitro of serum Amyloid P comPonent in normals and in a Patient with aa Amyloidosis
Clinical and Experimental Immunology, 2008Co-Authors: Philip N. Hawkins, Glenys A. Tennent, P Woo, M.B. PepysAbstract:Pure serum Amyloid P comPonent (SAP) was isolated from a normal donor Pool, from individuals with the different genotyPes of an MsPI restriction fragment length PolymorPhism (RFLP) linked to the SAP gene, and from a Patient with AA Amyloidosis. The SAP PreParations were all identical and all behaved as a single homogeneous sPecies in Polyacrylamide gel electroPhoresis, isoelectric focussing, reverse-Phase chromatograPhy, binding in vitro to PhosPhoethanolamine-SePharose (binding constant 2.4 x 10(7) l/mol) and AL Amyloid fibrils (1.6 x 10(8) l/mol), and binding to Amyloid dePosits in vivo in mice with casein-induced Amyloidosis. The in vivo metabolism of I-125-SAP from a single donor was normal and identical in three healthy individuals rePresenting the three different MsPI RFLP genotyPes. There is thus no frequent PolymorPhism of SAP in normal subjects, and SAP altered with resPect to the characteristics studied here is not a necessary condition for Pathogenesis of systemic AA Amyloidosis.
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binding of Pentraxins to different nuclear structures c reactive Protein binds to small nuclear ribonucleoProtein Particles serum Amyloid P comPonent binds to chromatin and nucleoli
Clinical and Experimental Immunology, 2008Co-Authors: M.B. Pepys, P J G Butler, Glenys A. Tennent, S E Booth, D G WilliamsAbstract:Binding of the human Pentraxin Plasma Proteins, C-reactive Protein (CRP) and serum Amyloid P comPonent (SAP), to the nuclei of human cells was studied using whole acute Phase serum as the source of the Proteins and confocal immunofluorescence microscoPy. CRP and SAP clearly bound to distinct, different structures. Double staining with MoAbs to the Sm D and Sm B/B' comPonents of small nuclear ribonucleoProteins confirmed that CRP bound exclusively to these Particles. As exPected, SAP bound to chromatin and, in addition, binding to the nucleolus was observed for the first time. These interactions demonstrated under relatively Physiological conditions, with native Pentraxins unseParated from serum and with nuclear constituents in situ, are likely to be of functional imPortance in vivo.
Winston L Hutchinson - One of the best experts on this subject based on the ideXlab platform.
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isolation and characterization of Pharmaceutical grade human Pentraxins serum Amyloid P comPonent and c reactive Protein for clinical use
Journal of Immunological Methods, 2012Co-Authors: M.B. Pepys, Palma Mangione, Glenys A. Tennent, Ruth J Gallimore, Stephan Ellmerich, Joanne Lloyd, David Graham, Graham W Taylor, Winston L HutchinsonAbstract:The human Pentraxin Proteins, serum Amyloid P comPonent (SAP) and C‐reactive Protein (CRP) are imPortant in routine clinical diagnosis, SAP for systemic Amyloidosis and CRP for monitoring the non‐sPecific acute Phase resPonse. They are also targets for novel theraPies currently in develoPment but their roles in health and disease are controversial. Thus, both for clinical use and to rigorously elucidate their functions, structurally and functionally intact, Pharmaceutical grade PreParations of the natural, authentic Proteins are required. We rePort here the Production from normal human donor Plasma and the characterization of the first such PreParations. ImPortantly, we demonstrate that, contrary to rePorts using recombinant Proteins and less well characterized PreParations, neither CRP nor SAP stimulate the release by human PeriPheral blood mononuclear cells in vitro of any TNFα, IL‐6 or IL‐8, nor does SAP cause release of IL‐1β or IL‐10. Furthermore neither of our PreParations was Pro‐inflammatory in mice in vivo.
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Immunoradiometric assay for human serum Amyloid P comPonent.
Journal of immunological methods, 2011Co-Authors: David J Millar, Winston L Hutchinson, Mark B. PepysAbstract:Human serum Amyloid P comPonent (SAP) is of increasing interest for its Possible Pathogenic role in Amyloidosis and Alzheimer's disease, and as a theraPeutic target in these conditions. We have develoPed and validated a robust and reProducible immunoradiometric assay (IRMA) for human SAP in serum, Plasma and cerebrosPinal fluid, and characterized the notable stability of human SAP immunoreactivity during storage of undiluted serum at 4°C and 37°C as well as frozen at -30°C. SAP values were also stable after rePeated freeze thawing of highly diluted serum samPles. The 100 fold dynamic range of the assay, 0.5-50 μg/L, encomPassed all values seen in blood and cerebrosPinal fluid, when tested at suitable dilutions, from both normal healthy individuals and Patients, including subjects receiving the SAP-dePleting drug, CPHPC. Furthermore by comParing the IRMA values in the Presence and absence of calcium, the new assay revealed interference due to the binding of CPHPC by SAP, which was markedly enhanced in heParinized Plasma. It is therefore essential that SAP assays in samPles from Patients on CPHPC be conducted in the absence of free calcium, in order to comPletely abrogate interference and determine the actual total SAP concentration. Estimates by the IRMA of SAP concentration in 49 serum samPles from Amyloidosis Patients corresPonded closely with those obtained by the established standard electro-immunoassay method and by a newly develoPed commercial ELISA kit (Hycult Biotechnology).
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antibodies to human serum Amyloid P comPonent eliminate visceral Amyloid dePosits
Nature, 2010Co-Authors: Karl Bodin, Palma Mangione, Winston L Hutchinson, Glenys A. Tennent, Stephan Ellmerich, Melvyn C Kahan, Andrzej Loesch, Janet A Gilbertson, Ruth J GallimoreAbstract:Accumulation of Amyloid fibrils in the viscera and connective tissues causes systemic Amyloidosis, which is resPonsible for about one in a thousand deaths in develoPed countries. Localized Amyloid can also have serious consequences; for examPle, cerebral Amyloid angioPathy is an imPortant cause of haemorrhagic stroke. The clinical Presentations of Amyloidosis are extremely diverse and the diagnosis is rarely made before significant organ damage is Present. There is therefore a major unmet need for theraPy that safely Promotes the clearance of established Amyloid dePosits. Over 20 different Amyloid fibril Proteins are resPonsible for different forms of clinically significant Amyloidosis and treatments that substantially reduce the abundance of the resPective Amyloid fibril Precursor Proteins can arrest Amyloid accumulation. Unfortunately, control of fibril-Protein Production is not Possible in some forms of Amyloidosis and in others it is often slow and hazardous. There is no theraPy that directly targets Amyloid dePosits for enhanced clearance. However, all Amyloid dePosits contain the normal, non-fibrillar Plasma glycoProtein, serum Amyloid P comPonent (SAP). Here we show that administration of anti-human-SAP antibodies to mice with Amyloid dePosits containing human SAP triggers a Potent, comPlement-dePendent, macroPhage-derived giant cell reaction that swiftly removes massive visceral Amyloid dePosits without adverse effects. Anti-SAP-antibody treatment is clinically feasible because circulating human SAP can be dePleted in Patients by the bis-d-Proline comPound CPHPC, thereby enabling injected anti-SAP antibodies to reach residual SAP in the Amyloid dePosits. The unPrecedented caPacity of this novel combined theraPy to eliminate Amyloid dePosits should be aPPlicable to all forms of systemic and local Amyloidosis.
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sustained Pharmacological dePletion of serum Amyloid P comPonent in Patients with systemic Amyloidosis
British Journal of Haematology, 2010Co-Authors: Julian D Gillmore, David J Millar, Winston L Hutchinson, Glenys A. Tennent, Helen J Lachmann, J R Gallimore, Hugh J B Goodman, M Offer, Aviva Petrie, Philip N. HawkinsAbstract:Serum Amyloid P comPonent (SAP) is a universal constituent of Amyloid dePosits and contributes to their formation and/or Persistence. We therefore develoPed CPHPC ((R)-1-[6-[(R)-2-carboxy-Pyrrolidin-1-yl]-6-oxo-hexa-noyl]Pyrrolidine-2 carboxylic acid), a novel bis(D-Proline) drug, to sPecifically target SAP and rePort here a first, exPloratory, oPen label Proof of PrinciPle study in systemic Amyloidosis. CPHPC Produced sustained, >95% dePletion of circulating SAP in all Patients and c. 90% reduction in the SAP content of the two Amyloidotic organs that became available. There were no significant adverse effects of either SAP dePletion or CPHPC itself. No accumulation of Amyloid was demonstrable by SAP scintigraPhy in any Patient on the drug. In hereditary fibrinogen Amyloidosis, which is inexorably Progressive, Proteinuria was reduced in four of five Patients receiving CPHPC and renal survival was Prolonged comPared to a historical control grouP. These Promising clinical observations merit further study.
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molecular dissection of alzheimer s disease neuroPathology by dePletion of serum Amyloid P comPonent
Proceedings of the National Academy of Sciences of the United States of America, 2009Co-Authors: Simon Kolstoe, Vittorio Bellotti, Ruth J Gallimore, Basil H Ridha, Nan Wang, Carol V Robinson, Sebastian J Crutch, G Keir, Riitta Kukkastenvehmas, Winston L HutchinsonAbstract:New theraPeutic aPProaches in Alzheimer's disease are urgently needed. The normal Plasma Protein, serum Amyloid P comPonent (SAP), is always Present in cerebrosPinal fluid (CSF) and in the Pathognomonic lesions of Alzheimer's disease, cerebrovascular and intracerebral Abeta Amyloid Plaques and neurofibrillary tangles, as a result of its binding to Amyloid fibrils and to Paired helical filaments, resPectively. SAP itself may also be directly neurocytotoxic. Here, in this unique study in Alzheimer's disease of the bis(d-Proline) comPound, (R)-1-[6-[(R)-2-carboxy-Pyrrolidin-1-yl]-6-oxo-hexanoyl]Pyrrolidine-2-carboxylic acid (CPHPC), we observed dePletion of circulating SAP and also remarkable, almost comPlete, disaPPearance of SAP from the CSF. We demonstrate that SAP dePletion in vivo is caused by CPHPC cross-linking Pairs of SAP molecules in solution to form comPlexes that are immediately cleared from the Plasma. We have also solved the structure of SAP comPlexed with PhosPhothreonine, its likely ligand on hyPerPhosPhorylated tau Protein. These results suPPort further clinical study of SAP dePletion in Alzheimer's disease and Potentially other neurodegenerative diseases.
Tae Takeda - One of the best experts on this subject based on the ideXlab platform.
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serum Amyloid P comPonent is the shiga toxin 2 neutralizing factor in human blood
Journal of Biological Chemistry, 2001Co-Authors: Tsuyoshi Kimura, Shinobu Tani, Yohichi Matsumoto, Tae TakedaAbstract:It has been suggested that some factor Present in human Plasma binds to Shiga toxin 2 (Stx2) and neutralizes it in vitro (Bitzan, M., Klemt, M., Steffens, R., and Muller-Wiefel, D. E. (1993) Infection 21, 140–145). This factor does not exist in other sPecies (CaPrioli, A., Luzzi, I., Seganti, L., Marchetti, M., Karmali, M., Clarke, I., and Boyd, B. (1994)Recent Adv. VTEC Infect. 353–356). Because analysis of this factor is imPortant to understanding the Pathology induced by Shiga toxin-Producing Escherichia coli, we Purified this factor from human Plasma and identified it. Purification was carried out by serially subjecting human Plasma to Con A-SePharose, DEAE-SePharose, hydroxyaPatite, and gel-filtration high Performance liquid chromatograPhy (HPLC), using Stx2-neutralizing activity as the indicator. The gel-filtration HPLC fraction yielded a single band on SDS-Polyacrylamide gel electroPhoresis. Twenty N-terminal amino acid residues of this fraction were analyzed and found to corresPond Perfectly to human serum Amyloid P comPonent (HuSAP). Because commercially available HuSAP also showed Stx2 binding and neutralizing activity, we identified this factor as HuSAP.