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Wehling C, Amon O, Bommer M, Hoppe B, Kentouche K, Schalk G, Weimer R, Wiesener M, Hohenstein B, Tönshoff B, Büscher R, Fehrenbach H, Gök ÖN, Kirschfink M. Monitoring of complement activation biomarkers and eculizumab in complement-mediated renal disorders. Clin Exp Immunol 2016; 187:304-315. [PMID: 27784126 DOI: 10.1111/cei.12890] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/07/2016] [Indexed: 12/18/2022] Open
Abstract
Various complement-mediated renal disorders are treated currently with the complement inhibitor eculizumab. By blocking the cleavage of C5, this monoclonal antibody prevents cell damage caused by complement-mediated inflammation. We included 23 patients with atypical haemolytic uraemic syndrome (aHUS, n = 12), C3 glomerulopathies (C3G, n = 9) and acute antibody-mediated renal graft rejection (AMR, n = 2), treated with eculizumab in 12 hospitals in Germany. We explored the course of complement activation biomarkers and the benefit of therapeutic drug monitoring of eculizumab. Complement activation was assessed by analysing the haemolytic complement function of the classical (CH50) and the alternative pathway (APH50), C3 and the activation products C3d, C5a and sC5b-9 prior to, 3 and 6 months after eculizumab treatment. Eculizumab concentrations were determined by a newly established specific enzyme-linked immunosorbent assay (ELISA). Serum eculizumab concentrations up to 1082 μg/ml point to drug accumulation, especially in paediatric patients. Loss of the therapeutic antibody via urine with concentrations up to 56 μg/ml correlated with proteinuria. In aHUS patients, effective complement inhibition was demonstrated by significant reductions of CH50, APH50, C3d and sC5b-9 levels, whereas C5a levels were only reduced significantly after 6 months' treatment. C3G patients presented increased C3d and consistently low C3 levels, reflecting ongoing complement activation and consumption at the C3 level, despite eculizumab treatment. A comprehensive complement analysis together with drug monitoring is required to distinguish mode of complement activation and efficacy of eculizumab treatment in distinct renal disorders. Accumulation of the anti-C5 antibody points to the need for a patient-orientated tailored therapy.
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Słabicki M, Lee KS, Jethwa A, Sellner L, Sacco F, Walther T, Hüllein J, Dietrich S, Wu B, Lipka DB, Oakes CC, Mamidi S, Pyrzyńska B, Winiarska M, Oleś M, Seifert M, Plass C, Kirschfink M, Boettcher M, Gołąb J, Huber W, Fröhling S, Zenz T. Dissection of CD20 regulation in lymphoma using RNAi. Leukemia 2016; 30:2409-2412. [PMID: 27560109 DOI: 10.1038/leu.2016.230] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Gretz N, Ecker-Tschirner KH, Kühnle HF, von Dahl K, Kirschfink M, Drescher P, Lasserre JJ, Strauch M. Practicability of the inulin plasma single-shot clearance. CONTRIBUTIONS TO NEPHROLOGY 2015; 81:220-8. [PMID: 2093501 DOI: 10.1159/000418757] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Wehling C, Kirschfink M. Tailored eculizumab regimen for patients with atypical hemolytic uremic syndrome: requirement for comprehensive complement analysis. J Thromb Haemost 2014; 12:1437-9. [PMID: 24942998 DOI: 10.1111/jth.12639] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Indexed: 12/01/2022]
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Grumach AS, Ceccon ME, Rutz R, Fertig A, Kirschfink M. Complement profile in neonates of different gestational ages. Scand J Immunol 2014; 79:276-81. [PMID: 24460650 DOI: 10.1111/sji.12154] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 01/13/2014] [Indexed: 11/29/2022]
Abstract
Blood levels of regulators of the complement system in preterm babies were reported in few studies only. The aim of this study was to set up a complement profile in premature and term babies focusing on the development of blood levels of MBL, key regulatory proteins and on classical pathway activity, which may allow an estimation of potential susceptibility to infection. Complement activity (CH50), levels of mannan-binding lectin (MBL), complement regulators (factors H and I, C1 inhibitor, properdin) and C3a as marker of complement activation were assessed in three groups of healthy newborns: (1) prematures (≤34 weeks); (2) late prematures (>34-<37 weeks) and (3) term neonates (≥37 weeks). CH50 increased with gestational age with lower titres in cord blood than in day 5 post-delivery venous blood. MBL concentrations were not significantly different among groups. Quantitative and functional C1 inhibitor were below adult normal range in prematures <34 weeks and lower in cord blood as compared to day 5. Factor I, factor H and properdin remained below adult values in all groups. Low C3a levels excluded that low complement titres were due to activation-induced consumption. These results demonstrate the relative immaturity of the complement system and its regulation, especially in premature infants.
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Wehling C, Amon O, Hoehenstein B, Pape L, Bommer M, Kirschfink M. Eculizumab drug monitoring in serum and urine opens new insights into therapy of complement-mediated nephropathies. Mol Immunol 2013. [DOI: 10.1016/j.molimm.2013.05.053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Chen Q, Wiesener M, Eberhardt H, Hartmann A, Kirschfink M, Amann K, Buettner M, Goodship T, Hugo C, Skerka C, Zipfel P. Complement deregulation in dense deposit disease by a novel CFHR2–CFHR5 hybrid protein. Mol Immunol 2013. [DOI: 10.1016/j.molimm.2013.05.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Lindner S, Chen Q, Kirschfink M, Nilsson B, Nilsson-Ekdahl K, Wolf G, Zipfel P. C3 convertase antibodies in membranoproliferative glomerulonephritis. Mol Immunol 2013. [DOI: 10.1016/j.molimm.2013.05.131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Mamidi S, Höne S, Kirschfink M. Improved antibody-induced cell-mediated killing (CDCC) and apoptosis of HER2 positive tumors after silencing membrane complement regulators. Mol Immunol 2013. [DOI: 10.1016/j.molimm.2013.05.125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Chmilewsky F, Jeanneau C, Laurent P, Kirschfink M, About I. C5a induces recruitment of STRO-1 pulp progenitor cells: Possible role in the regenerative process after dentin/pulp injury. Mol Immunol 2013. [DOI: 10.1016/j.molimm.2013.05.043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Chmilewsky F, Jeanneau C, Laurent P, Kirschfink M, About I. Pulp progenitor cell recruitment is selectively guided by a C5a gradient. J Dent Res 2013; 92:532-9. [PMID: 23603337 DOI: 10.1177/0022034513487377] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
It recently became evident that activation of the complement system also contributes to tissue regeneration after infection/injury. The complement-derived fragment C5a induces vascular modifications and attracts cells expressing its receptor (C5aR/CD88) to the site of infection and tissue injury. Besides inflammatory cells, various tissue cells express this receptor. We hypothesized that pulp progenitor cells, being exposed to local complement activation in caries lesions, may respond to C5a via the C5aR. Our work aimed at evaluating the ability of C5a to induce pulp progenitor cell migration that may link complement activation to dentin regeneration. Immunofluorescence analysis of third molar pulp sections showed perivascular localization of the mesenchymal stem cell markers STRO-1 and C5aR. RT-PCR on STRO-1-sorted pulp progenitor cells, co-expressing both STRO-1 and C5aR, revealed high C5aR mRNA levels. Experiments with the C5aR antagonist W54011 revealed that C5a specifically bound to progenitor cells via C5aR, inducing their selective migration toward the C5a gradient. Since we could also demonstrate C5b-9 formation by immunohistochemistry in carious teeth, our findings suggest that, upon local complement activation, C5a induces pulp progenitor cell migration, which may be critical in initiating the regenerative process after dentin/pulp injury.
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Grumach A, Ceccon M, Rutz R, Kirschfink M. Complement activity and regulation in premature, late premature and term neonates. Immunobiology 2012. [DOI: 10.1016/j.imbio.2012.08.072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Liu L, Li W, Li Z, Kirschfink M. Sublytic complement protects prostate cancer cells from tumour necrosis factor-α-induced cell death. Clin Exp Immunol 2012; 169:100-8. [PMID: 22774984 DOI: 10.1111/j.1365-2249.2012.04596.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Inflammation is a critical component of tumour progression. Although complement and tumour necrosis factor (TNF)-α potentially exert significant anti-tumour effects, both mediators may also promote tumour progression. It has been demonstrated that sublytic complement confers resistance on tumour cells not only against lytic complement, but also other danger molecules such as perforin. In low concentrations, TNF promotes survival of malignant cells rather than exerting cytotoxic activity. In this study, we tested if sublytic complement is able to interfere with TNF-mediated tumour cell killing. Our results demonstrate that either subcytotoxic concentrations of TNF or sublytic complement rescue prostate carcinoma cells (DU145) from TNF-α-mediated cell death. Upon pretreatment with low-dose TNF-α, but not upon pre-exposure to sublytic complement, TNF resistance was associated with the down-regulation of TNF receptor 1 (TNF-R1) expression. Complement-induced protection against TNF-mediated apoptosis accompanied the induction of anti-apoptotic proteins [B cell leukaemia/lymphoma (Bcl)-2 and Bcl-xL] at an early stage followed by inhibition of the TNF-induced decrease in the amount of Bcl-2 and Bcl-xL. Cell protection also accompanied the inhibition of caspase-8 activation, poly (ADP-ribose) polymerase (PARP)-1 cleavage and the activation of nuclear factor (NF)-κB. Our data extend our current view on the induction of tumour cell resistance against cytotoxic mediators supporting the role of the tumour microenvironment in mediating protection against the anti-cancer immune response.
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Marie-Lucile F, Laure-Helene N, Yosr C, Anne M, Fadi F, Levi C, Levi C, Meas-Yedid V, Daniliuc C, Karras A, Olivo-Marin JC, Mouthon L, Guiard E, Roland M, Guillevin L, Jacquot C, Nochy D, Thervet E, Chen Q, Skerka C, Uzonyi B, Lindner S, Licht C, Hoppe B, Riedl M, Kirschfink M, Habbich S, Wolf G, Strain L, Goodship TH, Zipfel PF, Kfoury H, Alsuwaida A, Alsaad K, Alhejaili F, Alghonaim M, Alwakeel J, Husain S, Aloudah N, Besso L, Besso L, Tamagnone M, Daidola G, Burdese M, Repetto L, Pasquale G, Colla L, Biancone L, Stratta P, Segoloni GP, Bacalja J, Bauer Segvic AM, Bulimbasic S, Pacic A, Knotek M, Sabljar Matovinovic M, Galesic K, Galesic Ljubanovic D, Zakharova E, Stolyarevich E, Vorobjova O, Tamouza H, Chemouny JM, Flamant M, Raskova Kafkova L, Demion M, Laurent M, Walker F, Julian BA, Tissandie E, Tiwari MK, Novak J, Camara NO, Benhamou M, Vrtovsnik F, Monteiro RC, Moura IC, Samavat S, Ahmadpoor P, Torbati P, Ghaderi R, Poorrezagholi F, Samadian F, Nafar M, MII A, MII A, Shimizu A, Kaneko T, Yasuda F, Fukui M, Masuda Y, Iino Y, Katayama Y, Muller C, Markovic-Lipkovski J, Simic-Ogrizovic S, Naumovic R, Cirovic S, Mitrovic D, Muller G, Wozniak A, Janicka-Jedynska M, Zurawski J, Kaczmarek E, Zachwieja J, Khilji S, Khilji S, Dorman T, O'kelly P, Lampty L, Leung K, Shadivan A, Varghese C, Walshe J, Saito T, Kawano M, Saeki T, Mizushima I, Yamaguchi Y, Imai N, Nakashima H, Umehara H, Shvetsov M, Popova O, Chebotareva N, Ivanov A, Bobkova I, Cremasco D, Ceol M, Peruzzi L, Mazzucco G, Giuseppina M, Vezzoli G, Cristofaro R, D'angelo A, Anglani F, Del Prete D, Coppolino G, Comi N, Bolignano D, Piraina V, Talarico R, Colombo A, Lucisano G, Fuiano G, Bernich P, Lupo A, Of Renal Biopsies TR, Rastaldi MP, Jercan OC, Messa P, Alexandru D, Mogoanta L, Jercan OC, Shvetsov M, Ivanov A, Uribe Villegas V, Popova O. Renal histopathology. Nephrol Dial Transplant 2012. [DOI: 10.1093/ndt/gfs242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Malina M, Kirschfink M, Boppel T, Fremeaux-Bacchi V, Schaefer F. Komplement-Blockade durch Eculizumab: neue Therapieoption auch bei Shigatoxin-assoziiertem hämolytisch-urämischem Syndrom. KLINISCHE PADIATRIE 2011. [DOI: 10.1055/s-0031-1273786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Lehmann T, Heger M, Münch S, Kirschfink M, Klar E. In vivo microscopy reveals that complement inhibition by C1-esterase inhibitor reduces ischemia/reperfusion injury in the liver. Transpl Int 2011. [DOI: 10.1111/j.1432-2277.2000.tb02101.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Bedarf JR, Russ M, Ott S, Keckel T, Kirschfink M, Unger JK. Influence of acidaemia and hypoxaemia on CVVH haemocompatibility in a porcine model. Nephrol Dial Transplant 2010; 25:2960-9. [DOI: 10.1093/ndt/gfq126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
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Li W, Geis N, Kirschfink M. Specific targeting of anti-CD59 siRNA by Herceptin®-conjugated liposomes improves complement-mediated cytotoxicity of breast carcinoma cells. Mol Immunol 2009. [DOI: 10.1016/j.molimm.2009.05.222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Guerra-Junior G, Grumach AS, de Lemos-Marini SHV, Kirschfink M, Condino Neto A, de Araujo M, De Mello MP. Complement 4 phenotypes and genotypes in Brazilian patients with classical 21-hydroxylase deficiency. Clin Exp Immunol 2009; 155:182-8. [PMID: 19137635 DOI: 10.1111/j.1365-2249.2008.03838.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The aim of this work was to analyse C4 genotypes, C4 protein levels, phenotypes and genotypes in patients with the classical form of 21-hydroxylase deficiency. Fifty-four patients from 46 families (36 female, 18 male; mean age 10.8 years) with different clinical manifestations (31 salt-wasting; 23 simple-virilizing) were studied. Taq I Southern blotting was used to perform molecular analysis of the C4/CYP21 gene cluster and the genotypes were defined according to gene organization within RCCX modules. Serum C4 isotypes were assayed by enzyme-linked immunosorbent assay. The results revealed 12 different haplotypes of the C4/CYP21 gene cluster. Total functional activity of the classical pathway (CH50) was reduced in individuals carrying different genotypes because of low C4 concentrations (43% of all patients) to complete or partial C4 allotype deficiency. Thirteen of 54 patients presented recurrent infections affecting the respiratory and/or the urinary tracts, none of them with severe infections. Low C4A or C4B correlated well with RCCX mono-modular gene organization, but no association between C4 haplotypes and recurrent infections or autoimmunity was observed. Considering this redundant gene cluster, C4 seems to be a well-protected gene segment along the evolutionary process.
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Odening KE, Li W, Rutz R, Laufs S, Fruehauf S, Fishelson Z, Kirschfink M. Enhanced complement resistance in drug-selected P-glycoprotein expressing multi-drug-resistant ovarian carcinoma cells. Clin Exp Immunol 2008; 155:239-48. [PMID: 19040611 DOI: 10.1111/j.1365-2249.2008.03817.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Multi-drug resistance (MDR) is a major obstacle in cancer chemotherapy. There are contrasting data on a possible correlation between the level of expression of the drug transporter P-glycoprotein (P-gp) and susceptibility to complement-dependent cytotoxicity (CDC). We therefore investigated the sensitivity of human ovarian carcinoma cells and their P-gp expressing MDR variants to complement. Chemoselected P-gp expressing MDR cells showed increased resistance to CDC associated with overexpression of membrane-bound complement regulatory proteins (mCRP) and increased release of the soluble inhibitors C1 inhibitor and factor I. MDR1 gene transfection alone did not alter the susceptibility of P-gp expressing A2780-MDR and SKOV3-MDR cells to CDC. However, subsequent vincristine treatment conferred an even higher resistance to complement to these cells, again associated with increased expression of mCRP. Blocking the function of P-gp with verapamil, cyclosporine A or the anti-P-gp-antibody MRK16 had no impact on their complement resistance, whereas blocking of mCRP enhanced their susceptibility to complement. These results suggest that enhanced resistance of chemoselected MDR ovarian carcinoma cells to CDC is not conferred by P-gp, but is due at least partly to overexpression of mCRP, probably induced by treatment with the chemotherapeutic agents.
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Zell S, Geis N, Rutz R, Schultz S, Giese T, Kirschfink M. Down-regulation of CD55 and CD46 expression by anti-sense phosphorothioate oligonucleotides (S-ODNs) sensitizes tumour cells to complement attack. Clin Exp Immunol 2007; 150:576-84. [PMID: 17903221 PMCID: PMC2219364 DOI: 10.1111/j.1365-2249.2007.03507.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Overexpression of one or more membrane-bound complement regulatory proteins (mCRPs) protects tumour cells against complement-mediated clearance by the autologous humoral immune response and is also considered as a barrier for successful immunotherapy with monoclonal anti-tumour antibodies. Neutralization of mCRPs by blocking antibodies, enzymatic removal or cytokine-mediated down-regulation has been shown to sensitize tumour cells to complement attack. In our study we applied, for the first time, anti-sense phosphorothioate oligonucleotides (S-ODNs) to knock down the expression of the mCRPs CD55 and CD46 with the aim of exploiting complement more effectively for tumour cell damage. Potent anti-sense oligonucleotides against CD55 and CD46 were identified by screening various target sequences (n = 10) for each regulator. S-ODN anti-CD55(687) reduced CD55 protein expression up to 84% and CD46 protein expression was inhibited up to 76% by S-ODN anti-CD46(85). Reverse transcription-polymerase chain reaction (RT-PCR) analysis revealed a similar reduction of the CD55 and CD46 mRNA levels, which argues for an RNAse H-dependent anti-sense mechanism. T47D, A549 and PC3 cells, representing breast, lung and prostate carcinoma, were used for functional studies. Dependent on the particular cell line, anti-sense-based inhibition of mCRP expression enhanced complement-dependent cytolysis (CDC) up to 42% for CD55 and up to 40% for CD46, and the combined inhibition of both regulators yielded further additive effects in T47D cells. C3 opsonization of CD55/CD46-deficient tumour cells was also clearly enhanced upon mCRP suppression. Due to the clinical applicability of S-ODNs, the anti-sense approach described in this study may offer an additional alternative to improve the efficacy of antibody- and complement-based cancer immunotherapy.
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Garcia-Huttenlocher H, Jurianz K, Kirschfink M. 2022 POSTER Influence of cytokines on the expression of membrane-bound complement regulatory proteins and on complement-mediated lysis on breast cancer cell lines T47D und BT474. EJC Suppl 2007. [DOI: 10.1016/s1359-6349(07)70784-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Licht C, Heinen S, Józsi M, Löschmann I, Saunders RE, Perkins SJ, Waldherr R, Skerka C, Kirschfink M, Hoppe B, Zipfel PF. Deletion of Lys224 in regulatory domain 4 of Factor H reveals a novel pathomechanism for dense deposit disease (MPGN II). Kidney Int 2006; 70:42-50. [PMID: 16612335 DOI: 10.1038/sj.ki.5000269] [Citation(s) in RCA: 166] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
We report a novel pathomechanism for membranoproliferative glomerulonephritis type II (MPGN II) caused by a mutant Factor H protein expressed in the plasma. Genetic analyses of two patients revealed deletion of a single Lys residue (K224) located within the complement regulatory region in domain 4 of Factor H. This deletion resulted in defective complement control: mutant protein purified from the plasma of patients showed severely reduced cofactor and decay-accelerating activity, as well as reduced binding to the central complement component C3b. However, cell-binding activity of the mutant protein was normal and comparable to wild-type Factor H. The patients are daughters of consanguineous parents. As both patients but also their healthy mother were positive for C3 nephritic factor, the mutant Factor H protein is considered relevant for unrestricted activation of the disease-causing activation of the alternative complement pathway. Replacement of functional Factor H by fresh frozen plasma (10-15 ml/kg/14 days) was well tolerated, prevented so far disease progression in both patients, and is in the long run expected to preserve kidney function.
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Grumach AS, Leitão MF, Arruk VG, Kirschfink M, Condino-Neto A. Recurrent infections in partial complement factor I deficiency: evaluation of three generations of a Brazilian family. Clin Exp Immunol 2006; 143:297-304. [PMID: 16412054 PMCID: PMC1809586 DOI: 10.1111/j.1365-2249.2005.02988.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/03/2005] [Indexed: 11/27/2022] Open
Abstract
We report here on the evaluation of a factor I-deficient Brazilian family (three generations, 39 members) with strong consanguinity. The complete factor I-deficient patients (n = 3) presented recurrent respiratory infections, skin infections and meningitis; one of them died after sepsis. They presented an impaired total haemolytic activity (CH50), low C3, low factor H and undetectable C3dg/C3d. Partial factor I deficiency was detected in 16 family members (normal low cut-off value was 25 microg/ml). Respiratory infections were the most common clinical occurrence among partial factor I-deficient relatives. Two of them were submitted to nephrectomy following recurrent urinary tract infections. An additional two heterozygous relatives presented with arthritis and rheumatic fever. Apparently, patients with partial factor I deficiency are also at higher risk for recurrent infections. Vaccination against capsulated bacteria and the eventual use of prophylactic antibiotics should be considered individually in this patient group.
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